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The transition to more environmentally friendly steel production methods has intensified research into hydrogen-based direct reduction (HyDR) of iron oxide pellets. The aim of this study is to systematically investigate the kinetics of the reduction process, the evolution of porosity and the resulting microstructural changes on the reduction behavior of high-quality pellets during HyDR of iron ore at different temperatures. A modified mathematical model is developed based on the shrinkage kernel model, taking into account both mass and heat transport in a hydrogen atmosphere. The effects of temperature, particle size and time on the reduction behavior of the pellets are investigated. The simulated results are validated and discussed by the results of a batch of iron oxide pellets consisting of ten almost spherical pellets subjected to the direct reduction process with pure hydrogen. The results show that the total energy input to the HyDR process is a complex balance of factors, including chemical reaction rates, diffusion dynamics and entropy generation. The increase in free volume and simultaneous decrease in pore diameter reflect the dynamic nature of the microstructure, which includes additional free volume and defects due to the volume discrepancies and associated stresses between the reactant and product phases. Furthermore, the data show that higher temperatures accelerate the reduction reactions, especially the transformation of wustite into metallic iron. This phase transition is characterized by a significant volume change that cannot be accommodated by elastic deformation alone, leading to the development of lattice defects such as cracks, creep pores and dislocations that serve as stress relief mechanisms. The trends for porosity change at 950 °C and 1000 °C observed in the experimental results are correct and in good agreement with the numerical and simulated results. [Display omitted] • Development of a model to evaluate HyDR kinetics and microstructural changes in iron oxide pellets. • Higher temperatures accelerate HyDR, which affects phase transitions and defect formation. • Temperature-induced porosity affects kinetics and gas diffusion despite tortuosity. • HyDR leads to stress defects and increased porosity in the microstructure. • The interaction of kinetics and entropy in the optimization of the HyDR process for steel was highlighted. [ABSTRACT FROM AUTHOR]

Dissociative identity disorder (DID) is characterised by, among others, subjectively reported inter-identity amnesia, reflecting compromised information transfer between dissociative identity states. Studies have found conflicting results regarding memory transfer between dissociative identity states. Here, we investigated inter-identity amnesia in individuals with DID using self-relevant, subject specific stimuli, and behavioural and neural measures. Data of 46 matched participants were included; 14 individuals with DID in a trauma-avoidant state, 16 trauma-avoiding DID simulators, and 16 healthy controls. Reaction times and neural activation patterns related to three types of subject specific words were acquired and statistically analysed, namely non-self-relevant trauma-related words (NSt), self-relevant trauma-related words from a trauma-avoidant identity state (St), and trauma-related words from a trauma-related identity state (XSt). We found no differences in reaction times between XSt and St words and faster reaction times for XSt over NSt. Reaction times of the diagnosed DID group were the longest. Increased brain activation to XSt words was found in the frontal and parietal regions, while decreased brain activity was found in the anterior cingulate cortex in the diagnosed DID group. The current study reproduces and amalgamates previous behavioural reports as well as brain activation patterns. Our finding of increased cognitive control over self-relevant trauma-related knowledge processing has important clinical implications and calls for the redefinition of "inter-identity amnesia" to "inter-identity avoidance". [ABSTRACT FROM AUTHOR]

• A mathematical model for the lyophilization process is capable of addressing the heterogeneity of thermal characteristics of different vial suppliers, according to the design space concept. • The critical parameters for the primary drying stage, as predicted by the model, were experimentally tested using sucrose and sodium chloride solutions rendering lyophilized products of homogenous quality independently of the suppliers and the position of the vials on the lyophilizer shelf. Primary drying is the most critical stage of the freeze-drying process. This work aimed to establish a design space for this process by means of mathematical modeling of the primary drying stage, capable of addressing the thermal characteristics of distinct vial suppliers. Modeling of primary drying was implemented on Microsoft Excel using steady-state heat and mass transfer equations at two extreme conditions as assessed by risk analysis, to predict product temperature and primary-drying time. The heat transfer coefficients (K v) of four different vial suppliers were experimentally determined, both, at the center and edge of the freeze-dryer's shelf. Statistically significant differences (ANOVA p <0.05) were observed between suppliers throughout the assessed pressure range. Overall, the average K ve /K vc (edge/center) ratio was higher than 1.6 for all suppliers due to the radiation effect. A design space for the drying process was established using mathematical modeling taking into account the K v of the worst-case supplier, in the shelf edge. A primary drying cycle was carried out at a shelf temperature of -25 °C and a chamber pressure of 45 mTorr for 8 % sucrose and at -10 °C and 75 mTorr for 5 % NaCl. Freeze-dried products with good cosmetic appearance were obtained for the four vial suppliers both, in the shelf center and edge. The results show that it is possible to predict and establish the critical parameters for the primary drying stage, under a design space concept, considering the differences in the K v of vial suppliers without adverse consequences on the quality of the finished freeze-dried product. [ABSTRACT FROM AUTHOR]

• MRI may reduce induction of labor rates for macrosomia in a hypothetical cohort. • Repeating Boulvain's trial using MRI would result in similar rates of shoulder dystocia. • There is possible clinical utility of MRI in the management of macrosomia. To simulate the outcomes of Boulvain's trial by using magnetic resonance imaging (MRI) for estimated fetal weight (EFW) as a second-line confirmatory imaging. Data derived from the Boulvain's trial and the study PREMACRO (PREdict MACROsomia) were used to simulate a 1000-patient trial. Boulvain's trial compared induction of labor (IOL) to expectant management in suspected macrosomia, whereas PREMACRO study compared the performance of ultrasound-EFW (US-EFW) and MRI-EFW in the prediction of birthweight. The primary outcome was the incidence of significant shoulder dystocia (SD). Cesarean delivery (CD), hyperbilirubinemia (HB), and IOL at < 39 weeks of gestation (WG) were selected as secondary outcomes. A subgroup analysis of the Boulvain's trial was performed to estimate the incidence of the primary and secondary outcomes in the true positive and false positive groups for the two study arms. Sensitivity, specificity, positive and negative predictive values (PPV, NPV) for the prediction of macrosomia by MRI-EFW at 36 WG were calculated, and a decision tree was constructed for each outcome. The PPV of US-EFW for the prediction of macrosomia in the PREMACRO trial was 56.3 %. MRI-EFW was superior to US-EFW as a predictive tool resulting in lower rates of induction for false-positive cases. Repeating Boulvain's trial using MRI-EFW as a second-line test would result in similar rates of SD (relative risk [RR]:0.36), CD (RR:0.84), and neonatal HB (RR:2.6), as in the original trial. Increasing the sensitivity and specificity of MRI-EFW resulted in a similar relative risk for SD as in Boulvain's trial, but with reduced rates of IOL < 39 WG, and improved the RR of CD in favor of IOL. We found an inverse relationship between IOL rate and incidence of SD for both US-EFW and MRI-EFW, although overall rates of IOL, CD, and neonatal HB would be lower with MRI-derived estimates of fetal weight. The superior accuracy of MRI-EFW over US-EFW for the diagnosis of macrosomia could result in lower rates of IOL without compromising the relative advantages of the intervention but fails to demonstrate a significant benefit to justify a replication of the original trial using MRI-EFW as a second-line test. [ABSTRACT FROM AUTHOR]

A comprehensive approach to creating a control system for the shape of the radio-reflecting surface of a large-size space reflector is considered. Large-aperture space antennas are used for satellite communications and space exploration. The design of these structures is one of the most promising areas. Ensuring the specified characteristics of the reflector is directly related to maintaining the specified shape of the radio-reflective netting. Developing a control system for the shape of the active antenna surface is an urgent task. Optimizing this process makes it possible to accomplish the mission during the operational period effectively. The paper evaluates the effects of perturbations on a large-scale structure operating in outer space. A method for adjusting the geometry of the frontal network is proposed. This allows for improved communication between spacecraft and ground stations, which is very important for the safety of space flights. The conductive parts of the reflector are considered to transmit energy and control signals to the actuators. The application results of various control algorithms of the executive device making it possible to correct the netting considering the minimization of energy costs and oscillations of the structure are shown. According to the simulation results, the optimal algorithm of the target criteria hierarchy showed greater stability in terms of convergence in the presence of measurement noise and disturbances, which allows it to be applied in real time. This algorithm is supposed to be used in the future when creating a prototype of the system for controlling the shape of the radio-reflective surface of a large-size space reflector using its current-conducting structural parts. • The design of a system for setting up and maintaining a radio-reflective network fabric has been developed. • Algorithms are developed to minimize energy when setting up a radio-reflective mesh. • The optimal algorithm of the control allows solving the problem in real time. • The method for transmitting energy and control signals through the use of conductive structural parts of the reflector is proposed. [ABSTRACT FROM AUTHOR]

With the unique structure of multi-core compound droplets, they are increasingly used in various industrial production fields, material fabrication, biological sciences, medicine, and other numerous promising large-scale applications. This study focuses on using a front tracking method to study the dynamics of a multi-core compound droplet as it moves within a ratchet microchannel. The dynamics of the multi-core droplet is assessed by deformation (determined by elongation deformation indices, and surface indentation) and the transit time of the droplet within the microchannel. The presence of the ratchet region in the microchannel increases deformation and reduces the transit time of the compound droplets. Increasing the number of ratchets leads to faster droplet motion but has no significant effect on the deformation of the compound droplet. The results indicate that the parameters such as the capillary number, microchannel geometry (i.e., number of ratchets and neck radius), droplet size and structure significantly impact the compound droplet dynamics. The compound droplet radius equal to 0.3 times the microchannel radius results in the most significant elongation deformation. The number of core droplets has minimal effect on the deformation and transit time of the compound droplet. This study provides a profound insight into the dynamics of multi-core compound droplets in a ratchet microchannel and contributes a better understanding of their behavior and potential applications in various fields. [ABSTRACT FROM AUTHOR]

Immunization programs globally have played a pivotal role in reducing mortality rates. However, the effectiveness of these programs often falls short of the intended coverage targets, primarily due to challenges within the supply chain, storage facilities, and distribution processes. Notably, a substantial percentage of vaccine wastage has been observed in numerous countries, thereby imposing a significant financial burden on immunization initiatives, and presenting a formidable challenge to policymakers. This paper undertakes a comprehensive study of the financial dynamics inherent in an immunization program within the context of India. Employing a systems perspective, we scrutinize the intricate interactions among various cost factors. Through a five-year system dynamics simulation, we derive insights into the amplified financial constraints resulting from vaccine wastage and the inefficiencies associated with shared personnel. Furthermore, our analysis extends to evaluate the impact of an additional investment aimed at enhancing the quality of the cold chain infrastructure and health worker proficiency on the overall funds of the immunization program. This research contributes to a nuanced understanding of the financial intricacies of immunization programs, offering valuable insights for policymakers and stakeholders seeking to optimize program efficiency and resource allocation. [ABSTRACT FROM AUTHOR]

The fluid catalytic cracking (FCC) process transforms heavy wastes into lighter, more valuable (naphtha, light olefins and gases) products. However, the unit's byproducts contain a large quantity of CO 2 , which contributes to global warming. As a result, the purpose of this research was to increase the production of valuable products such as light olefins, naphtha, and hydrogen while reducing environmental impacts using the water gas shift reaction, with sensitivity analysis for three parameters (riser height, FCC feed temperature, and inlet naphtha mass flow). As a result of increasing the riser height, the output of light olefins (45%) and gases (32%) increased. Furthermore, the amount of hydrogen produced increases with a decrease in riser height (about 6%) and an increase in inlet naphtha mass flow (about 8%). Energy and exergy assessments were also carried out. It was determined that FCC had the lowest exergy destruction with a contribution of 23 MW when compared to its energy usage of 172 MW. The cooler, on the other hand, was one of the process's most energy-consuming (25%) and damaging (26%). As a result, this technique can lessen environmental effects by absorbing 125 tons of CO 2 every hour and producing 3484 kg/h of hydrogen. Economic evaluations were also undertaken, and the results revealed that the cooler has the lowest exergoeconomic factor (1%) while the FCC unit contributes the most (95%). The fractionator column is also the most expensive device in the whole process. [Display omitted] • Increasing the riser height greatly enhances the production of gases by 32% and light olefins by 45%, but decreases hydrogen production by 200 kg/h. • Increasing feed temperature, and coke production, reduce carbon dioxide emissions by 5%. • Solar energy saves 24 million tons of CO 2 emissions when compared to using gas as an energy source. • The FCC process consumes the second most energy (20%) and is the least exergy-destructive (90% efficiency) equipment within the process. • FCC unit had the greatest economic exergy factor (95%). [ABSTRACT FROM AUTHOR]

• Explore the relationship between industrial solid waste and socioeconomic. • Analyze the flow relationships among different sectors of industrial solid waste. • Determine the industrial solid waste discharge responsibility for each sector. • Identify the key sectors for industrial solid waste discharge. • Simulate industrial solid waste reduction measures. Rapid economic development inevitably leads to the discharge of a large amount of common industrial solid waste (CISW), which not only pollutes the environment but also restricts economic development in turn. In this study, a dynamic common industrial solid waste (DCISW) model is developed to analyze the retrospectively CISW development in Shanghai from 2000 to 2017 and simulate prospectively multi-perspective emission reduction measures. Specifically, the dynamic linkages between CISW and socio-economics are established at both the systematic and sectoral levels through input–output analysis, ecological network analysis, and related socio-economic indicators. Abatement measure simulations are conducted using RAS and other methods. The findings reveal that the growth of CISW in Shanghai is closely related to its fast-growing economy. The Others sector (OS) receives the most CISW from other sectors, while the Mining industry (MI) sends the most CISW to others. From production-based, consumption-based, and income-based perspectives, Chemical Products (CP) consistently remain the largest contributors. For the proposed waste generation intensity (WGI) indicator, the Mining industry (MI) is regarded as the main sector in all three perspectives. Moreover, the MI consistently emerges as the key sector of the system. CISW simulations indicate that improving the MI emission technology and increasing the MI output value will be top priorities for CISW emission reduction in Shanghai. This study is expected to provide scientific support to address the CISW problem in Shanghai and other similar fast-growing metropolises. [ABSTRACT FROM AUTHOR]

Alumina-based multilayer laminates with layers of varied porosities and ceramic fiber reinforcements, which can be achieved by including paper-derived ceramic layers, are interesting candidates for chemically stable and thermal shock resistant materials. In order to investigate the complex sintering behavior of these laminates, the sintering of each alumina layer contained within a laminate, each one with its individual sintering anisotropy and sintering shrinkage, has to be considered separately. For this purpose, sintering curves are determined by dilatometry measurements, serving a consecutive examination by an analytical model. Modeling parameters specific to each layer, are applied in finite-element-type sintering simulations for symmetrical multilayer laminates. Differences in the sintering shrinkages may cause internal stresses at layer interfaces and, in turn, may influence the thermal and mechanical properties of multilayer laminates after sintering. Accordingly, the prediction of developing internal stresses within alumina-based multilayer laminates by the presented sintering simulations is a key aspect of this study. [Display omitted] • Individual laminates sintering dilatometry. • Anisotropic sintering assessment by analytic modeling. • Finite element simulation of multilayer laminates sintering. [ABSTRACT FROM AUTHOR]

As the utilization of nuclear energy continues to expand, there is a growing focus on the development of lightweight and efficient nuclear shielding composites. In this paper, novel WB X /Al (x = 1, 2, 4) composites were designed based on shielding performance. The effects of reinforcement type, volume fraction, and material thickness on the 60Co and 137Cs γ-rays, fast and thermal neutron shielding performances were simulated. The results show that WB/Al composites offer better development potential compared to WB 2 /Al or WB 4 /Al composites. Additionally, a predictive model for the γ-ray shielding effectiveness of WB/Al composites, based on the areal density of tungsten, was proposed. The fabrication process involved mechanical ball milling and spark plasma sintering to fabricate 30 vol% WB/Al composites, with optimization of ball milling time, sintering temperature, and holding time. As a result, a novel nuclear radiation protection composite with uniform composition, a relative density of 97 %, and flexural strength of 527 MPa was acquired. [ABSTRACT FROM AUTHOR]

Nowadays, renewable energy sources are integral to programs for the development of electric power systems. It is established that modern renewable generation units and energy storage systems utilize power electronic-based interfaces, such as voltage source converters, to convert power. On the one hand, the utilization of a voltage source converter provides certain advantages, such as the absence of a direct link to the network, the ability to operate on all quadrants of the PQ diagram, and the possibility of connecting renewable generation units to a weak network. On the other hand, the widespread use of renewable generation units utilizing voltage source converters reduces the overall inertia of the electric power system. However, excessive use of power electronic converters in the network leads to a significant increase in harmonic pollution, thereby introducing fresh challenges to ensuring safe and stable operation of the electric power system. To ensure the dependable operation of an electric power system with renewable energy sources units and energy storage systems based on the voltage source converter, it is essential to update the control system of the voltage source converter to meet the requirements for traditional generation as part of the electric power system. This paper presents the outcome of the power oscillation damping controller application implemented in the voltage source converter, which enhances the electric power system's stability. [ABSTRACT FROM AUTHOR]

Digital light processing (DLP) has emerged as a highly promising 3D printing technology, which is due to its ability to fabricate components and structures with low cost and high precision. The DLP is, therefore, applicable in a wide range of fields. The phenomenon of light-scattering plays a dominant role in the DLP manufacturing process, but the specific impact of ceramic particles on the distribution of incident light remains unclear. The present study has, therefore, focused on studying the effect of ceramic particles on light-scattering by performing extensive theoretical finite element simulations. The aim was then to improve the curing quality of the DLP 3D printing process. More specifically, spherically shaped particles with a uniform distribution, lower duty ratios, or materials with lower refractive indices were necessary conditions for enhancing the printing precision due to the mitigated lateral light scattering effects. The overall results of this study have provided valuable guidance for the control of the light-induced curing in the 3D printing process of ceramics, thereby facilitating advancements in ceramic-based fabrication techniques. [ABSTRACT FROM AUTHOR]

The chemical industry serves as a global economic backbone and it is an intensive consumer of conventional energy. Due to the depletion of fossil fuels and the emission of greenhouse gases, it is necessary to analyze energy supply solutions based on renewable energy sources in this industrial sector. Unlike other sectors, such as residential or service industries, which have been thoroughly analyzed by the scientific community, the use of renewable energies in the chemical industry remains comparatively less examined by the scientific community. This article studies the use of an energy supply system based on photovoltaic technology or a PEM fuel cell for a styrene production industry, analyzing the integration of energy storage systems such as batteries, as well as different uses for the surplus hydrogen produced by the facility. The most interesting conclusions of the article are: (1) the renewable microgrid considered is viable both technically and economically with a discounted payback period between 5.4 and 6.5 years, using batteries as an energy storage system; and (2) the use of hydrogen as energy storage system for a styrene industry is not yet a viable option from an economic point of view. • Including photovoltaic energy for a styrene plant is profitable, with a DPP of 6 years. • Consuming purified hydrogen steam to produce electricity in a PEM fuel cell is not yet economically viable. • Using the by-product hydrogen for thermal energy production is profitable due to savings in natural gas and CO 2 emissions. [ABSTRACT FROM AUTHOR]

Two prefusion F protein-based vaccines, Arexvy and Abrysvo, have been approved by Health Canada for protecting older adults against respiratory syncytial virus (RSV)-associated lower respiratory tract disease. We estimated the health benefits and cost-effectiveness of these vaccines under a publicly funded single-dose vaccination program in Ontario that targets residents of long-term care homes (LTCHs). Additionally, we evaluated an extended program that broadens vaccination to include community-dwelling older adults. A discrete-event simulation model was parameterised with the burden of RSV disease including outpatient care, hospitalisation, and death among adults aged 60 years or older in Ontario, Canada. Accounting for direct and indirect costs (in 2023 Canadian dollars) associated with RSV-related outcomes, we calculated the net monetary benefit using quality-adjusted life-year (QALY) gained, and determined the range of price-per-dose (PPD) for vaccination programs to be cost-effective from both healthcare and societal perspectives over two RSV seasons. The incremental cost-effectiveness ratio (ICER) was calculated to estimate the additional costs required to gain one QALY. Using a willingness-to-pay of $50,000 per QALY gained, we found that vaccinating 90% of residents in LTCHs with Arexvy would be cost-effective from a societal perspective for a PPD up to $163, producing a mean ICER value of $49,984 (95% CI: $47,539 to $52,704) per QALY gained with a two-year budget impact of $463,468 per 100,000 older adults. The reduction of hospitalizations was estimated at 7.0% compared to the no-vaccination scenario. Extending the program to include community-dwelling older adults with a 74% coverage akin to influenza vaccination, Arexvy remains cost-effective for a PPD up to $139, with a mean ICER value of $49,698 (95% CI: 48,022 to 51,388) per QALY gained and a two-year budget impact of $8.63 million. Compared to the no-vaccination scenario, the extended program resulted in a 57.3% reduction in RSV-related hospitalisations. Vaccinating residents of LTCHs against RSV disease would be cost-effective depending on PPD; extending the program to community-dwelling older adults would provide substantial health benefits, averting significant direct healthcare costs and productivity losses. [ABSTRACT FROM AUTHOR]

A main shift in the competitive landscape of technology development is in 3D printing of complex articles made of variety of materials due to faster manufacturing and less human error in the production. In fact, it seems to be a viable candidate for the construction of structures for terrestrial and extraterrestrial life in future. Thus, new or damaged equipment in space explorations could be replaced instantly, and habitats could be manufactured using 3D printing in varying gravitational fields in the solar system. Among 3D printing materials, HDPE is commonly used in the projects, such as a prototype manufacturing or pipes or damp-proof membrane. This study initially focused on the preliminary design of the self-sustaining mini ethylene production plant from Martian atmosphere with scale-out architecture. UniSIM® was integrated with MATLAB® via CAPE-OPEN extension to design mini-ethylene production plant at low gravity. Ethylene capacity was found as 17.71 tons/year for 100 modules. [ABSTRACT FROM AUTHOR]

Pressure swing adsorption(PSA) based gas separation technology is widely applied in chemical industries, especially in hydrogen purification. Its complex mechanism and non-steady state feature restrict the separation performance adjustment and application on efficient gas utilization. Process simulation, machine learning and modelling combined innovating gas management methodology is proposed in this paper to perform accurate gas separation for natural gas based syngas mixture. VB script program is employed to drive Aspen adsorption simulation, and then classical and regression tree(CART), polynomial regression(PNR) and surrogate model are comprehensively used to perform machine learning. Consequently, the coefficient matrix is obtained to quantify the separation performance. This method holds the potential for broader application in refineries and SPCs hybrid hydrogen network, facilitating the comprehensive utilization of hydrogen containing gases. Case study results show this methodology can conserve natural gas and gas productivity by 21.3 %, as well as carbon emission by 8211.6 Nm3/h. This work highlights the promising application of digital twin technology within the chemical industry, showcasing how process simulation, machine learning, and modeling can collectively revolutionize gas management and resource conservation. [Display omitted] • Novel PSA based gas allocation instead of gas separation technology. • Simulation, modelling and machine learning combined gas accommodating methodology. • An insight technology for integration of refinery and SPC. • A novel gas allocation method for zero waste of hydrogen. • An insight application of digital twin technology for gas efficient utilization. [ABSTRACT FROM AUTHOR]

In this study, 304 SS/Al 2 O 3 ceramic structural parts were successfully prepared by laser heat source biasing using AgCuTi as filler. The method removes residual thermal stresses by retaining unfused 304 SS (stainless steels), provides protection to the Al 2 O 3 ceramics, and connects the two sides of the substrate using the wettability of the AgCuTi filler. Based on the 304 SS/Al 2 O 3 connectivity, the Gibbs free energy changes of Ti–Fe and Ti–Cu compounds at the weld were calculated from the thermodynamics perspective to determine the possible phases. The temperature field of the joint was also investigated using finite element simulation to analyze the temperature changes in the fusion zone, the interface I (304 SS/AgCuTi), and the interface II (AgCuTi/Al 2 O 3) under different welding parameters, and predict the welding parameters that can achieve an effective connection without destroying the Al 2 O 3 ceramics, which were experimentally verified. The maximum tensile strength of the joints was 94.9 MPa when the laser power was increased from 372 W to 432 W. The maximum tensile strength of the joints was 90.5 MPa when the laser speed was increased from 440 mm/min to 630 mm/min. The maximum tensile strength of the joints was 89 MPa when the laser offset was increased from 1.4 mm to 1.9 mm. By analyzing the microstructure, it was found that brittle intermetallic compounds (IMCs) such as FeTi and Cu 2 Ti were generated at interface I, which was the main factor affecting the strength of the joint. Many Ag(s,s) and Cu(s,s) solid solutions were found at AgCuTi and interface II. By analyzing the microstructure, the interface organization of the joint is composed of 304 SS + α-Fe/γ-Fe + FeTi/Cu 2 Ti + Ag(s,s)/Cu(s,s) + Ti 2 Cu + Al 2 O 3. Finally, the Arrhenius function calculates the diffusion coefficients and diffusion concentrations of Ti and Fe elements. [ABSTRACT FROM AUTHOR]

• G. indica extract exhibited time and dose dependent α-amylase inhibitory activity. • Reported major phytocompounds of G. indica were traced by LC-MS analysis. • Simulations predicted gambogic acid is mainly responsible for anti-amylase activity. • Gene set analysis showed G. indica modulated the PI3K-Akt pathway to counter T2DM. Garcinia indica Choisy is traditionally used to manage diabetes mellitus, also used in various herbal formulations, and is indicated as an insulin sensitizer. The present study investigates the hydroalcoholic extract of G. indica Choisy rind as an α-amylase inhibitor, followed by the identification of the probable lead hits via a computational approach. LC-MS analyse were carried out. In vitro assays for alpha amylase were performed at concentrations of G. indica ranging from (1000–125 µg/mL) and acarbose (25–1.56 µg/mL) with inhibition times ranging from 5th to 30th min. In silico study was performed based upon the bioactives traced from LC-MS data retrieved from the PubChem database and predicted for probable targets of diabetes mellitus, followed by a drug-likeness score, probable side effects, and an ADMET profile. In addition, molecular docking and the dynamics of the representative complex were explored using AutoDock Vina and Gromac. In vitro study revealed IC 50 values of 400.5, 526.07, 728.05, 792.7, 848.3, and 897.5 µg/mL and acarbose displayed IC 50 values of <1.56, 6.6, 10.46, 12.6, 14.14, and 15.24 µg/mL respectively. LC-MS analysis identified 17 bioactives, of which 13 showed positive druglikness; among them, 5 bioactives were predicted to modulate AMY2A. The gene set enrichment analysis revealed that AMY2A and gambogic acid possessed high edge counts, with the lowest binding energy of gambogic acid- AMY2A (-11.7 kcal/mol), followed by amentoflavone (-10.6 kcal/mol), volkensiflavone (-9.3 kcal/mol), fukugcide (-8.8 kcal/mol), and garcinol (-7.7 kcal/mol) when compared with acarbose- AMY2A (-7.7 kcal/mol), which also indicates high stability up to 100 ns in molecular simulation. Hydroalcoholic extract of G. indica rind α-amylase inhibitory activity, may be due to the presence of gambogic acid and other bioactives. Thus, it can be speculated that G. indica may possess anti-diabetic activity by reducing the post prandial glucose level. This needs to be further confirmed via enriched fractions or pure substances with inhibitory activity to develop Traditional medicine based new drugs [ABSTRACT FROM AUTHOR]

• Feasibility of rapid epidemic panel involving population-based cohort. • Four protection levels against severe COVID-19 based on literature synthesis. • Protection levels based on vaccination, previous infection, and immunity status. • Model-based estimates on SARS-CoV-2 hospitalizations with varying scenarios. • Varying scenarios on transmissibility, variants, and boosters inform policymakers. Throughout the SARS-CoV-2 pandemic, Germany like other countries lacked adaptive population-based panels to monitor the spread of epidemic diseases. To fill a gap in population-based estimates needed for winter 2022/23 we resampled in the German SARS-CoV-2 cohort study MuSPAD in mid-2022, including characterization of systemic cellular and humoral immune responses by interferon-γ-release assay (IGRA) and CLIA/IVN assay. We were able to confirm categorization of our study population into four groups with differing protection levels against severe COVID-19 courses based on literature synthesis. Using these estimates, we assessed potential healthcare burden for winter 2022/23 in different scenarios with varying assumptions on transmissibility, pathogenicity, new variants, and vaccine booster campaigns in ordinary differential equation models. We included 9921 participants from eight German regions. While 85% of individuals were located in one of the two highest protection categories, hospitalization estimates from scenario modeling were highly dependent on viral variant characteristics ranging from 30-300% compared to the 02/2021 peak. Our results were openly communicated and published to an epidemic panel network and a newly established modeling network. We demonstrate feasibility of a rapid epidemic panel to provide complex immune protection levels for inclusion in dynamic disease burden modeling scenarios. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, 304 SS/Al 2 O 3 ceramic structural parts were successfully prepared by laser heat source biasing using AgCuTi as filler. The method removes residual thermal stresses by retaining unfused 304 SS (stainless steels), provides protection to the Al 2 O 3 ceramics, and connects the two sides of the substrate using the wettability of the AgCuTi filler. Based on the 304 SS/Al 2 O 3 connectivity, the Gibbs free energy changes of Ti–Fe and Ti–Cu compounds at the weld were calculated from the thermodynamics perspective to determine the possible phases. The temperature field of the joint was also investigated using finite element simulation to analyze the temperature changes in the fusion zone, the interface I (304 SS/AgCuTi), and the interface II (AgCuTi/Al 2 O 3) under different welding parameters, and predict the welding parameters that can achieve an effective connection without destroying the Al 2 O 3 ceramics, which were experimentally verified. The maximum tensile strength of the joints was 94.9 MPa when the laser power was increased from 372 W to 432 W. The maximum tensile strength of the joints was 90.5 MPa when the laser speed was increased from 440 mm/min to 630 mm/min. The maximum tensile strength of the joints was 89 MPa when the laser offset was increased from 1.4 mm to 1.9 mm. By analyzing the microstructure, it was found that brittle intermetallic compounds (IMCs) such as FeTi and Cu 2 Ti were generated at interface I, which was the main factor affecting the strength of the joint. Many Ag(s,s) and Cu(s,s) solid solutions were found at AgCuTi and interface II. By analyzing the microstructure, the interface organization of the joint is composed of 304 SS + α-Fe/γ-Fe + FeTi/Cu 2 Ti + Ag(s,s)/Cu(s,s) + Ti 2 Cu + Al 2 O 3. Finally, the Arrhenius function calculates the diffusion coefficients and diffusion concentrations of Ti and Fe elements. [ABSTRACT FROM AUTHOR]

Focused assessment with sonography for trauma (FAST) is a valuable ultrasound procedure in emergency settings, and there is a need for evidence-based education in FAST to ensure competencies. Immersive virtual reality (IVR) is a progressive training modality gaining traction in the field of ultrasound training. IVR holds several economic and practical advantages to the common instructor-led FAST courses using screen-based simulation (SBS). This prospective, interventional cohort study investigated whether training FAST using IVR unsupervised and out-of-hospital was non-inferior to a historical control group training at a 90 min SBS course in terms of developing FAST competencies in novices. Competencies were assessed in both groups using the same post-training simulation-based FAST test with validity evidence, and a non-inferiority margin of 2 points was chosen. A total of 27 medical students attended the IVR course, and 27 junior doctors attended the SBS course. The IVR group trained for a median time of 117 min and scored a mean 14.2 ± 2.0 points, compared with a mean 13.7 ± 2.5 points in the SBS group. As the lower bound of the 95% confidence interval at 13.6 was within the range of the non-inferiority margin (11.7–13.7 points), training FAST in IVR for a median of 117 min was found non-inferior to training at a 90 min SBS course. No significant correlation was found between time spent in IVR and test scores. Within the limitations of the use of a historical control group, the results suggest that IVR could be an alternative to SBS FAST training and suitable for unsupervised, out-of-hospital courses in basic FAST competencies. [ABSTRACT FROM AUTHOR]

The ionospheric total electron content (TEC) is a critical parameter for space weather and Global Navigation Satellite System (GNSS) applications. Since 1998, the Ionospheric Working Group of the International GNSS Service (IGS) has been generating global ionospheric maps using data from hundreds of GNSS stations. However, the uneven geographical distribution of these observations has resulted in significant variations in TEC map accuracy, particularly in marine areas where observations are scarce or absent. In this study, we introduce Argo data as additional observations to enhance the accuracy of global ionospheric modeling. Argo data consists of measurements collected by more than 1,000 robotic floats deployed across the world's oceans. By utilizing the NeQuick model and considering the geographic coordinates of both IGS stations and Argo buoys, we simulate the ionospheric Slant Total Electron Content (STEC). This approach allows us to examine the impact of integrating Argo data into global ionospheric modeling and evaluate its effectiveness. The results indicate a significant improvement in the overall accuracy of the model after incorporating Argo data. Furthermore, by increasing the model's degree, a better global fit is achieved. It eliminates noticeable overestimation or underestimation of TEC, especially evident at a degree of 30. As the availability and uniform distribution of observations improve, the model demonstrates higher accuracy and enhanced global performance. [ABSTRACT FROM AUTHOR]

• Riders moved significantly further away from overtaking vehicles equipped with Adaptive Headlamp Systems (AHS) compared to a control condition. • AHS has the potential to improve bicycling safety in nighttime conditions when lighting conditions are poor. Introduction : The risk of motor vehicle-bicyclist crashes and fatalities is greater during nighttime than daytime lighting conditions, even though there are fewer cyclists on roadways at night. Vehicle Adaptive Headlamp Systems (AHS) aim to increase the visibility of bicyclists for drivers by directing a spotlight to illuminate bicyclists on or near the roadway. AHS technology also serves to alert bicyclists to the approaching vehicle by illuminating the road beneath the rider and by projecting a warning icon on the roadway. Method: Here, we examined how bicyclists respond to different AHS designs using a large screen, immersive virtual environment. Participants bicycled along a virtual road during nighttime lighting conditions and were overtaken by vehicles with and without an AHS system. The experiment included five treatment conditions with five different AHS designs. In each design a box of white light was projected beneath the rider; in four of the designs an icon was also projected on the road that varied in color (white or red) and position (to the left of the rider at midline or to the left of the front wheel). Participants in the control condition experienced only non-AHS vehicles. Results: We found that riders in all AHS treatment conditions moved significantly farther away from overtaking vehicles with AHS systems, whereas riders in the control condition did not significantly move away from overtaking vehicles without AHS systems. Practical Applications: The experiment demonstrates that AHS has potential to increase bicycling safety by influencing riders to steer away from overtaking vehicles. [ABSTRACT FROM AUTHOR]

The Lennard-Jones (LJ) fluid, named after mathematician-physicist-chemist Sir John Lennard-Jones (1894–1954), occupies a special place among fluids. It is an ideal entity, defined as the fluid whose particles interact according to the Lennard-Jones potential. This paper expounds the history of the LJ fluid to throw light on the tensions between theory and computational practice. The paper argues for the following claims. Firstly, the computational approach—even prior to the computer—pragmatically aims at prediction, not truth. Secondly, computer simulation methods, especially "molecular dynamics" (MD), triggered a change in epistemology. Now, simulated model fluids became targets of investigation in their own right. The urge for prediction turned the LJ fluid into the most investigated fluid in engineering thermodynamics. Thirdly, MD took a huge upswing in the 1990s, due to exploratory options in simulation. We discuss how, under these conditions, predictive success might be fraught with problems of reproducibility. [ABSTRACT FROM AUTHOR]

To retrieve and synthesize the literature on existing mental health-specific microsimulation models or generic microsimulation models used to examine mental health, and to critically appraise them. All studies on microsimulation and mental health published in English in MEDLINE, Embase, PsycINFO, and EconLit between January 1, 2010, and September 30, 2022, were considered. Snowballing, Google searches, and searches on specific journal websites were also undertaken. Data extraction was done on all studies retrieved and the reporting quality of each model was assessed using the Quality Assessment Reporting for Microsimulation Models checklist, a checklist developed by the research team. A narrative synthesis approach was used to synthesize the evidence. Among 227 potential hits, 19 studies were found to be relevant. Some studies covered existing economic-demographic models, which included a component on mental health and were used to answer mental-health-related research questions. Other studies were focused solely on mental health and included models that were developed to examine the impact of specific policies or interventions on specific mental disorders or both. Most models examined were of medium quality. The main limitations included the use of model inputs based on self-reported and/or cross-sectional data, small and/or nonrepresentative samples and simplifying assumptions, and lack of model validation. This review found few high-quality microsimulation models on mental health. Microsimulation models developed specifically to examine mental health are important to guide healthcare delivery and service planning. Future research should focus on developing high-quality mental health-specific microsimulation models with wide applicability and multiple functionalities. • A cursory glance of the literature suggests there are few microsimulation models on mental health. Furthermore, there has only been 1 systematic review examining simulation modeling (eg, microsimulation, discrete event simulation, Markov modeling) applied to mental health. However, this review is now outdated; moreover, it only synthesized the literature and did not critically appraise the models found. • This review focused only on studies that used microsimulation models on mental health and found few microsimulation models on the topic. Moreover, this review critically appraised the models and found that few models were of high quality because many used model inputs based on self-reported and/or cross-sectional data and small and/or nonrepresentative samples; few undertook model validation. • The findings and recommendations from this review will be relevant to researchers and decision makers looking to build robust mental-health-specific microsimulation models that can be used to inform policy development and guide healthcare delivery and service planning. [ABSTRACT FROM AUTHOR]

Blow molded plastic liners (BMPLs) for on-board Type IV compressed gaseous hydrogen (CGH2) storage tanks consist of a high-molecular-weight polymer wall that serves as a permeation layer for hydrogen gas. This paper presents the latest numerical model integrated in the Blow View software for predicting the hydrogen permeation in a BMPL. The prediction model is based on Fick's solution-diffusion laws, with pressure and temperature dependent transport properties, for steady/unsteady state permeation regimes through a polymeric wall. An overview of key simulation results for an industrial BMPL for a CGH2 tank, as well as the adopted methodology addressing the challenge to optimize the wall thickness for light weighting and permeability performance, are also presented. • Numerical model for H 2 permeation in homogeneous amorphous polymeric liner. • Fick's solution-diffusion model with pressure and temperature dependent transport properties. • Simulation tool for the design, manufacturing and optimization of BMPL for a CGH2 tank. • BMPL optimization to improve the thickness uniformity for light weighting. • BMPL permeability prediction based on the thickness distribution and material selection. [ABSTRACT FROM AUTHOR]

This manuscript describes reflectance-based vicarious calibration exercise of the Airborne Visible InfraRed Imaging Spectrometer - Next Generation (AVIRIS-NG) sensor during its second phase of observation campaigns over the Indian subcontinent. Vicarious calibration methods are one of the significant approaches that have been practiced successfully for the absolute radiometric calibration of various spaceborne and airborne sensors to ascertain its desired performance in terms of data quality and its accuracy. Calibration campaigns were performed for AVIRIS-NG sensor during its phase-2 campaign overpass at the Desalpar (25th March 2018) and Amarapur (27th March 2018) calibration sites of Gujarat, India. Results from ground-based measurements of atmospheric conditions and surface reflectance including descriptions of the test sites are summarized in this work. Based on the in-situ data and images from the AVIRIS-NG sensor, the at-sensor apparent radiances are simulated using the 6SV radiative transfer model. The comparison shows good agreement between AVIRIS-NG measured radiance and 6SV simulated apparent radiance at the two calibration sites using desert aerosol model. The gains (spectrally) derived agree to within ∼ 2 % each other. Furthermore, an analysis is performed to determine or identify systematic and random errors, and the overall uncertainty is evaluated for reflectance-based method (total uncertainty of less than 4 % spectrally). [ABSTRACT FROM AUTHOR]

This work presents a Density Functional Theory (DFT) study of the single perovskite CsXH 3 (X = Co, Zn). We used the CASTEP code to perform first-principles calculations and investigate the hydrogen storage properties of CsXH 3 (X = Co, Zn). We calculated the structural, Hydrogen, mechanical, electronic, optical, and thermal properties of CsXH 3 (X = Co, Zn) perovskite materials for hydrogen storage applications. Electronic properties reveal that CsXH 3 (X = Co, Zn) has a metallic behavior. The calculated value of formation energy is −0.47 eV/atom and −0.18 eV/atom for CsCoH 3 and CsZnH 3 , respectively, which means that the studied materials are synthesizable and thermodynamically stable. Our results show that CsXH 3 (X = Co, Zn) is a promising material for hydrogen storage, as it exhibits high hydrogen storage capacity. The gravimetric ratio values are 2.82 wt% and 3.09 wt% for CsCoH 3 and CsZnH 3 , respectively. The determined elastic constants show that CsXH 3 (X = Co, Zn) is mechanically stable. Our study provides valuable insights into using single perovskite CsXH 3 (X = Co, Zn) as a potential material for hydrogen storage applications. • Performance of DFT study for CsXH 3 (X = Co, Zn) perovskites materials for hydrogen storage applications. • The elastic constants values show that CsXH 3 (X = Co, Zn) is mechanically stable. • Calculated formation energy is −0.47 and −0.18 for CsCoH 3 and CsZnH 3 respectively. • The studied materials are synthesizable, thermodynamically stable and are most suitable for hydrogen storage applications. [ABSTRACT FROM AUTHOR]

Recently, with the aim of developing clean and efficient energy systems, various designs based on chemical looping combustion and reforming have been suggested. This study proposed and investigated the production of ultra-pure hydrogen in dual-purpose integrated zero-emission reforming (UPH 2 -DPIZER) process based on the sorption-enhanced chemical looping steam methane reforming (SECLSMR). This process is proposed on the basis of reduction in the emissions of carbon dioxide as well as the simultaneous generation of pure hydrogen and syngas for use in a wide range of applications. One of the most novel aspects of this research is that the proposed UPH 2 -DPIZER process can reduce or eliminate carbon dioxide emissions because all the produced and chemisorbed CO 2 can be applied directly in the reforming process without any additional purification. Furthermore, the synthesized 30 wt%NiO-5wt.%CeO 2 /Al 2 O 3 oxygen carrier was examined using the X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM) techniques along with evaluation in SECLSMR process. The attained results of experimental tests are applied to adapt and validate the simulations of novel proposed process. The other objectives of this study are the reduction in required energy for the whole process along with reduction in the direct consumption of fossil fuels. The experiments showed high H 2 /CO molar ratio of 36 at 550 °C with appropriate methane conversion of about 74 %, while at 750 °C, nearly a complete conversion of CH 4 occurs. The obtained results from the simulation of proposed UPH 2 -DPIZER showed the production of ultra-pure hydrogen along with syngas with H 2 /CO molar ratio of about 1 with negligible CO 2 release. [Display omitted] • A novel process for producing pure H 2 and syngas without CO 2 emission was proposed. • NiO–CeO 2 /Al 2 O 3 OC was synthesized and investigated in the SECLSMR experimentally. • The final products of the novel proposed process are ultrapure H 2 and synthesis gas (H 2 :CO ∼ 1:1). • The attained results exposed high energy and exergy efficiency of novel process. [ABSTRACT FROM AUTHOR]

With the increasing demand for clean hydrogen (H 2) energy, new emerging technologies for in-situ H 2 production from hydrocarbon reservoirs have attracted the attention of researchers and industry. This presents an opportunity for the petroleum industry to contribute to the energy transition. One technology in the field pilot stage is in-situ combustion gasification (ISCG). However, the mechanism behind this process is not fully understood and additional experimental and modeling work is required. To address this issue, we developed a laboratory-scale simulation model for ISCG. Statistical methods were combined to investigate the sensitivity and interactions of different parameters that control the process. The results showed that 34 mol.% H 2 can be generated at 800 °C. Higher temperatures yielded higher H 2 concentrations with coke gasification and water-gas shift reactions dominating hydrogen generation. This study provides valuable knowledge about the process and lays a foundation for future lab-scale ISCG experiments. [Display omitted] • An in-situ combustion gasification laboratory-scale simulation model was developed. • The mechanism of H 2 generation via in-situ combustion gasification was described. • A concentration of 34 mol.% of H 2 in the gas mixture was produced at 800 °C. • H 2 O has an important role during H 2 generation via in-situ combustion gasification. • High temperatures are more favorable for the occurrence of H 2 generation reactions. [ABSTRACT FROM AUTHOR]

This study proposed a two-stage gasification (TSG) process of pulverized coal to allow for hydrogen-rich (HR) production. The balance flow of this process is constructed using Aspen Plus software. Gasification pressure (GP), steam-coal ratio (SCR), and oxygen-coal ratio (OCR) influences on the process are studied, and the operating conditions are optimized to achieve the maximum hydrogen production. The results show that the GP mainly affects the pyrolysis of pulverized coal in the low-temperature section. Reducing the GP is conducive to hydrogen production. However, it requires heat supplement to raise temperature and maintain the balance of the system. An increase in the SCR is better for hydrogen production, leading to a decrease in the gasification temperature. When the SCR is higher than 0.3, the steam utilization rate decreases obviously. With an increase in the OCR, the gasification temperature continues to increase, and hydrogen production first increases and then decreases, reaching its peak at approximately 0.5. The optimal parameter combination is as follows: the SCR is 0.3; the OCR is 0.53; water is used as the medium for temperature regulation uses, and the water supply is 0.12 kg/kg coal; oxygen is used to raise the temperature of the low-temperature section, and the oxygen supply is 0.18 kg/kg coal. The hydrogen production rate of the optimal working condition is 77.78 g/kg coal, which is 48.38% higher than that of single-stage gasification. • A two-stage gasification process of pulverized coal for hydrogen-rich is proposed. • The optimum condition of this process is obtained by Aspen Plus. • H 2 production rate of the optimum condition is 77.78 g/kg coal. • H 2 production rate is 48.38% higher than that of single-stage gasification. [ABSTRACT FROM AUTHOR]

The hydrogen and oxygen bubbles covering the electrode surface will reduce the reaction rate of water electrolysis and increase energy consumption. Adding ultrasonic to the electrolytic cell can improve the escape velocity of bubbles on the electrode surface by oscillation and cavitation effect. In this paper, the effects of ultrasound on the performance of water electrolysis under different working conditions are studied by experiment and numerical simulation. Firstly, the polarization curves and bubble flow patterns under different positions of the ultrasonic vibrator and electrode were obtained through experiments. And then, the flow model of the electrolytic cell with ultrasonic is constructed, which considers the mass transfer between the gas and liquid phases and the acoustic flow phenomenon caused by cavitation. The results revealed that, due to the reflection of the wall and the transmission process of the ultrasonic in the electrolyte, the electrode position has a significant impact on the current density when the ultrasonic vibrator is located on the right side of the electrolytic cell, which can be increased by 2.40%–22.70% at different electrode positions compared with that without ultrasound. The influence of operating parameters on the flow field inside the electrolyzer was obtained through numerical simulation. As a result, appropriate loading methods and operating conditions can maximize the effectiveness of ultrasound. [Display omitted] • Improper ultrasonic loading method increases energy consumption. • Wall conditions have a significant impact on the performance of water electrolysis. • The bubble flow morphology on the electrode surface was observed. • A flow field model of electrolyzer with ultrasonic was constructed. [ABSTRACT FROM AUTHOR]

In this paper, the use of inhibitor for preventing the detonation propagation in the mixtures of hydrogen with air is studied in numerical experiments. The hydrocarbon propylene additive is used as an inhibitor. The paper presents the results of two-dimensional simulations of the cellular structure of a detonation wave. The dependence of cellular structure on the content of inhibitor is studied for different conditions of detonation initiation. The results allow determining critical content of inhibitor preventing from detonation onset. Experimental validation of results for hydrogen-air mixtures is provided. • Chemical methods for suppressing detonation in hydrogen-air mixture studied. • Numerical model for hydrogen-air mixture with propylene additive developed. • The effectiveness of hydrocarbon inhibitor for suppressing hydrogen-air detonation. • Comparison of simulation with experiment provide good agreement. [ABSTRACT FROM AUTHOR]

Erythropoiesis-stimulating agents (ESAs) have been a common treatment for anemia associated with chronic kidney disease (CKD), while 10–20 % of patients continue to suffer from persistent anemia despite receiving ESA treatments. Our previous findings suggested that intensive ESA usage can cause resistance by depleting the erythroid precursor cells. Here, we used a mechanism-based pharmacokinetic/pharmacodynamic (PK/PD) model of ESAs and conducted simulations to evaluate the influence of dose regimens and other factors (such as administration route, individual PK/PD parameters, types of ESAs, and disease status) on ESA resistance with instantaneous dose adaptations in healthy populations and anemic patients. The simulated results show that instantaneous dose-adaptation can reduce ESA resistance, but up to 30 % of subjects still ended up developing ESA resistance in healthy populations. The S max is markedly higher in hypo-responders than in normal-responders, while hypo-responders possess fewer precursors and experience a faster decline compared to normal-responders. There is a ceiling effect of increasing ESA dosage to improve HGB responses and reduce ESA resistance, and the limit is lower in anemic patients compared to healthy populations. Subcutaneous administrations and ESAs with longer half-lives lead to stronger HGB responses and less resistance at equivalent doses. Taken together, this study indicates that precursor depletion contributes to ESA resistance and dose regimens can greatly influence the occurrence of ESA resistance. Furthermore, ESA treatment for patients showing ESA resistance should avoid continuously increasing doses and instead consider stimulating the renewal of precursors. [ABSTRACT FROM AUTHOR]

In the present paper, we report the numerical results of the solidification process of a liquid drop enclosing an air bubble, i.e., a hollow drop, on an inclined surface. The surface is tilted from 0° (corresponding to a horizontal surface) to 90° (corresponding to a vertical surface), and the contact angle of the drop ranges between 60° and 130°. The drop is deformed while solidification happens in the presence of volume expansion. This volume change results in the formation of a tip at the drop top. The tip becomes more asymmetric as the tilting angle, i.e., the surface angle, increases. However, the solidification time is not affected by the surface angle. During the initial stage of solidification, the drop liquid accumulates to the bottom, by gravity, and thus results in lowering the bubble position. The bubble then moves upwards due to buoyancy force. It stops moving as it is trapped by solidification. A larger bubble reduces the tip shift. We also consider the effect of the Bond number and the Stefan number on solidification. [ABSTRACT FROM AUTHOR]

We present a numerical study of the thermal migration of a compound droplet attached to a horizontal substrate. The different constant temperatures are applied to the left and right boundaries of the computational domain. The compound droplet contains one inner core. The problem is solved by using a front-tracking technique associated with the finite difference method. The investigated parameters include the radius ratio (R i o) of the inner droplet and the equivalent radius of the outer droplet (R i o varied in the range of 0.2 to 0.7), the viscosity ratio (μ o m) of the outer to middle fluids (μ o m varied in the range of 0.1 to 2.4), and the static contact angle θ e (θ e varied in the range of 60° to 120°). The results reveal that the inner droplet drives the compound droplet towards the hot region as its radius is sufficiently large (R i o ≥ 0.6). The compound droplet moves towards the cold region as the value of R i o is less than 0.6. Increasing the viscosity of the outer fluid (by increasing μ o m) or θ e causes the compound droplet to move towards the hot region. The trajectory of the centroid of the inner droplet is also investigated. [ABSTRACT FROM AUTHOR]

Digital Reference Objects (DROs) are mathematical phantoms that can serve as a basis for evaluating MR image quality (IQ) in an objective way. Their main purpose is to facilitate the establishment of fully automated and perfectly reproducible IQ metrics to objectively compare different algorithms in MR image formation in a standardized manner. They also allow to re-build parts of standard phantoms. We sample DROs directly in k -space, using analytical formulas for the continuous Fourier transform of primitive shapes. We demonstrate this DRO approach by applying a state-of-the-art CNN-based denoising algorithm that is robust to varying noise levels to noisy images of the resolution section of the well-known ACR phantom for IQ assessment, reconstructed from both measured and simulated k -space data. Applying the CNN-based denoising algorithm to the measured and simulated version of the ACR phantom resolution section produced virtually identical results, as confirmed by visual and quantitative comparison. DROs can help guide technology selection during the development of new algorithms in MR image formation, e.g. , via deep learning. This could be an important step towards reproducible MR image formation. [ABSTRACT FROM AUTHOR]

The analysis of the thermal damages in Notre-Dame de Paris is necessary to estimate the impact of the dramatic 2019 fire on the remaining structure prior to reconstruction. In doing so, the large amount of data being generated creates a benchmark environment to test the relevance of numerical fire models in the unconventional configuration of a medieval roof. While being an uncontrolled and complex configuration, it can provide insights regarding the relevance of numerical tools for fire risk assessment in historic buildings. Analysing the thermal degradation of the Lutetian limestone in a vault of the choir, experimental techniques are developed to track the in-depth maximum temperature profile reached during the fire. Numerical simulations of the fire development in the roof space then aim at replicating the observations through the evaluation of the heat flux impinging the vaults during the fire. These simulations are carried out using Fire Dynamic Simulator, which requires a large range of assumptions prior to any simulation regarding materials, geometry, meshing and scale. These assumptions are described and pave the way to a future sensitivity analysis to confront the upcoming outcomes of the simulations with the experimental observations. [ABSTRACT FROM AUTHOR]

Model-based systems engineering (MBSE) is an emerging methodology not only in the field of spacecraft systems engineering. The key objective is to store the whole system design in one single source of truth system model. The continuously maintained and customizable open-source MBSE tool Virtual Satellite developed by German Aerospace Center (DLR) offers a framework for storing such a system model. Since the open-source 3D computer aided design (CAD) software FreeCAD has a dedicated Virtual Satellite workbench for importing the 3D model file generated by Virtual Satellite, it is possible to export the 3D model from Virtual Satellite, apply changes to it in FreeCAD, and afterwards reimport it in Virtual Satellite. This paper presents a workflow implementation to conduct automated steady-state and transient thermal analyses using the Virtual Satellite system model as a basis, utilizing the aforementioned features. Part of this effort was to extend Virtual Satellite by thermal modeling capabilities, such as material parameters, surface characteristics, thermal interfaces, boundary conditions and further relevant aspects. With custom Java applications, so-called "Apps", all aspects of the system model relevant for a thermal analysis are exported from Virtual Satellite and written to accordingly generated text files. Moreover, the before described 3D model export is used to export the model to FreeCAD. The FreeCAD Python console, in combination with the finite element method (FEM) workbench, is used to create a script that executes meshing, application of the boundary and initial conditions, as well as identification of contacts between parts and application of the specified contact conductance values. The obtained files form a complete thermal model and can be fed directly into the open-source FEM software CalculiX for executing the thermal analysis. Then, the result can be processed by an additional Virtual Satellite App. To account for the space thermal environment an additional feature was added to the FreeCAD script. The feature uses orbit information obtained from external mission analysis tools to calculate the approximate combined heat load from Sun, Earth infrared, and albedo radiation at each time point in the specified simulation time interval. This new workflow allows to execute quick thermal analyses at an early design stage and therefore opens new opportunities in the evaluation of different system designs, as early as in a concurrent engineering study. Configuration parameters are provided that also allow more sophisticated analyses in later development phases, such as custom mesh definition and local mesh refinement. • Thermal design process of spacecraft relies on engineer's experience in early stages. • Potential help for the thermal design process is thermal simulation. • Thermal simulations require significant manual setup effort. • Created workflow automates simulation setup and result feedback. • Data for simulation setup maintained in MBSE system model. [ABSTRACT FROM AUTHOR]

We present a low-cost and easily accessible adaptation system to perform stereotactic procedures in infants. We used an adaptive device consisting of a headband with a plaster bandage, cotton bandage roll, and gauze bandages. Prior to its clinical application, the device was tested in our neuroscience laboratory using a simulation model of a size similar to that of a 5-month-old infant, during which no complications arose. The headband cast technique was subsequently reproduced in a 5-month-old patient, serving as a fixation point for the placement of a Micromar frame for biopsy of a thalamic lesion. A stereotactic biopsy was successfully performed in a 5-month-old patient using a headband cast to secure the stereotactic frame. This method enabled precise targeting of the selected site, resulting in a histopathological diagnosis without any associated complications. The adaptive device is safe, easily accessible, and reproducible, facilitating the performance of stereotactic diagnostic procedures in infants, accurately reaching the planned objective without causing injuries or additional complications. [ABSTRACT FROM AUTHOR]

Permanent breast seed implant (PBSI) brachytherapy is a promising treatment that has the potential to be widely utilized with increased standardization, optimization, and robustness. Excellent early efficacy and very high patient acceptance were reported, however, to further evaluate and improve planning strategies, a framework to quantify plan robustness to implant uncertainties is necessary. In this study, we aim to quantify clinical seed displacement using an automated algorithm and develop and validate a PBSI post-implant dosimetry simulation framework to evaluate PBSI plan robustness to implant uncertainties. Clinical PBSI seed displacements were quantified for 63 consecutive patients. A PBSI simulator was developed in Matlab (2020) by resampling clinical seed displacements and computing a range of possible post-implant dosimetry outcomes under various seed displacement scenarios. Simulations were performed retrospectively on 63 previous clinical plans to evaluate plan robustness to seed displacement. Mean seed displacement for the whole cohort was 10 ± 6 mm. A clinical seed displacement database was established and a user interface was developed for the simulation framework. For all clinical plans, the median (range) value of simulated median ETV V90 in various seed displacement scenarios was 97.8% (87.5–100%). A PBSI postimplant dosimetry simulation framework was developed and validated. Simulation results showed that the current PTV planning margin is sufficient to provide adequate postimplant dose coverage of ETV. This simulator can be used to evaluate plan robustness to seed displacement and will facilitate future research in improving PBSI planning methods. [ABSTRACT FROM AUTHOR]

In the Chemical Mechanical Planarization (CMP) process for semiconductor wafer fabrication, the polishing pads need to be continuously conditioned to ensure appropriate surface characteristics, which causes wear to the pads and subsequently affects the quality of CMP. Tuning the conditioning parameters is typically determined through expensive experimental trials. An effective pad conditioning simulation platform to model the conditioning process can significantly reduce the time and cost of the process development cycle. However, to mimic the real-life pad conditioning process, the simulation needs to track hundreds or even thousands of micro-sized diamond tips to check the contact points on the pads continuously during the conditioning process that spans many hours. This makes simulating pad conditioning over the entire pad for the duration of the process very challenging. In this work, we propose a low-cost numerical approach for simulating the pad conditioning process based on a collocation grid method and parametric mapping. Important numerical aspects such as time step size characterization, jump-over ratio, simulation efficiency, and error control are systematically analysed and discussed. Several benchmark examples are performed to evaluate the effectiveness of the proposed method. • An efficient algorithm for simulating CMP pad conditioning process. • Collocation grids with parametric mapping for flexible density map resolution and efficient contact tracing. • Possible error analysed with numerical validations. • Formulations of time-step-size estimation provided with verification. • Numerical studies illustrating the proposed methodology's effectiveness. [ABSTRACT FROM AUTHOR]

Water electrolysis coupled with renewable electricity systems is one of the most promising ways that will contribute to making the energy transition toward zero carbon emissions possible. This study aims to perform a technical-economic analysis of large-scale hydrogen production facilities through the simulation and optimization of hybrid renewable energy systems that use wind turbines and photovoltaic panels. Five Moroccan cities are subjected to the approach. The PV/wind ratio, net present cost, Levelized cost of hydrogen, storage capacity, and water desalination cost are analyzed. The results show that combining photovoltaic panels and wind turbines helps produce low-cost hydrogen in Morocco, especially in Dakhla with 2.54$/kg. It's the lowest cost in Morocco compared to previous studies. The results also show the importance of using hydrogen tanks to store energy. Finally, the cost of water desalination can be neglected, as it only represents between 0.12% and 0.35% of the net present costs. • Analysis of hydrogen production from the combination of wind turbine and PV panels. • Morocco has the potential to compete in the hydrogen market, with 2.54$/kg. • Desalination cost doesn't exceed 1% of the total cost of hydrogen systems. • Increasing the production flexibility can reduce the LCOH by 17%. [ABSTRACT FROM AUTHOR]

Background: Fundamentals of endoscopic surgery (FES) completion is mandatory for certification by the American Board of Surgery (ABS). As early simulation and competency assessment can bolster development of trainee proficiency, we sought to determine the optimal timing for FES examination by evaluating pass rates based on training level and previous endoscopic experience. Methods: PGY2-5 residents at a university-based medical center who were novice to FES were assigned to complete FES training and testing. Training year, prior endoscopic experience, and FES exam scores were recorded with pre- and post-test surveys. Results: Most residents in the program (88%) were able to complete FES training and testing within a single academic year. Most required only a single faculty-led session (88%) to feel confident to take the exam, augmented by varying numbers of independent practice sessions (50% 1–2, 19% 3–5, 27% > 5). After training, most (84%) felt confident that they would pass the exam, and 93% did so on their first attempt. While higher written exam scores were noted in the PGY5 group, there were no other statistically significant differences in overall pass rates or technical exam scores based on PGY level (p = 0.24). A number of previously completed endoscopic cases did not correlate with exam scores (p = 0.24 written, p = 0.91 technical). Conclusion: Fundamentals of endoscopic surgery (FES) certification can be successfully completed by junior level general surgery residents regardless of previous endoscopic experience. Moving this exam to earlier training years can benefit resident development and preparedness in the clinical setting without negatively impacting pass rates. [ABSTRACT FROM AUTHOR]

The rise in fluoroquinolone concentrations in wastewater caused significant concern due to their potential acute toxicity to living organisms. A novel eco-friendly adsorbent, crosslinked potato starch ester, was used to remove ciprofloxacin from a simulated aqueous solution by a batch adsorption process and used its obtained parameters to solve mathematical modeling. With a maximum adsorption capacity of 243.90 mg/g, the ciprofloxacin adsorption on crosslinked potato starch ester was suitable for the Langmuir isotherm model. The kinetics of ciprofloxacin adsorption showed that the pseudo-first-order kinetic model was a good fit for the adsorption process. Thermodynamic parameters exhibited that ciprofloxacin adsorption onto crosslinked potato starch ester was exothermic, achievable, and spontaneous. Finally, the process is simulated under various operating conditions using the mathematical model of a fixed bed continuous adsorption column. According to the results, under optimal operation conditions of inlet fluid velocity, particle size, bed height, and initial ciprofloxacin concentration with values 0.002 m/s, 1.2 mm, 0.2 m, and 143.4 mg/L, respectively, the highest dynamic adsorption capacity was 18.75 mg/g. [Display omitted] • Crosslinked potato starch ester, a eco-friendly adsorbent, was synthesized for removing ciprofloxacin from simulated wastewater. • Mathematical for the fixed bed continuous adsorption column was developed to simulate the process • Optimum operation conditions and fundamental design factors resulted in maximum dynamic adsorption capacity. [ABSTRACT FROM AUTHOR]

Solar sails are an attractive technology for propellant-free propulsion, especially in small satellites with tight power and mass budgets. Several recent missions have shown promising applications of solar sails for nanosatellite orbital control in low Earth orbit (LEO). They enable easier access to and removal from high-altitude orbits. Since solar radiation pressure produces torques in addition to forces, a solar sail can also be used for low-power attitude control. Few missions have exploited this effect. In response, this paper proposes a new nanosatellite mission concept, only achievable by combined orbit-attitude control via solar sail: the sunflower mission, for high-altitude wide-area Earth observation. A realistic sail design meeting the mission requirements is obtained via parametric analysis and comprehensive review of past missions. A pyramid-shaped sail is proposed for the mission, and its advantages and drawbacks are analysed. The dynamics are evaluated using a high-fidelity numerical simulator with all relevant physical perturbations in LEO. The imaging objectives are successfully achieved over a multi-year duration. The sail also provides propellant-free orbit insertion from a low-altitude launch orbit, and fast de-orbit at end-of-life. It uses less power and has a smaller stowed size than several competitor technologies for orbit-attitude control of LEO nanosatellites. [Display omitted] • Sunflower mission proposed for wide-area small satellite Earth observation in LEO. • A pyramid-shaped solar sail provides low-power orbit and attitude control. • Propellant-free orbit raising from a low deployment altitude reduces launch cost. • Passive Sun pointing enables low-power attitude control for remote sensing. • Propellant-free orbit lowering enables quick de-orbit at end-of-life. [ABSTRACT FROM AUTHOR]

At present, detonation principles are widely used for propulsion purposes. Stable initiation of detonation and its sustainable propagation are the key factors for safe operation of detonation chambers. In this paper, the evolution of the cellular structure of detonation waves under the condition of non-uniform initiation is investigated within the frames of two-dimensional simulations in a stoichiometric mixture of hydrogen with air. The dependence on cellular structure on the heterogeneity of initiation sources, chemical kinetic mechanism is studied. The simulation results are compared with experimental data. It is demonstrated, that in case of detonation decay after switching off initiators the flow structure essentially depends on heterogeneity of initiator, while in achieving the self-sustaining propagation mode the wave structure becomes independent on initiation conditions and "forgets" initial heterogeneity. • Two-dimensional simulations of the cellular structure of a detonation wave. • The dependence on cellular structure on the heterogeneity of initiation sources, chemical kinetic mechanism is studied • On achieving the self-sustaining propagation mode the wave structure becomes independent on initiation conditions and "forgets" initial heterogeneity • Comparison of simulation results with experimental data demonstrates a good agreement. [ABSTRACT FROM AUTHOR]