Additional Requirements Research Articles

Overcoming clay structure challenges in lithium recovery from boron waste using high‐temperature pressure acid leaching

AbstractBoron mines contain significant amounts of lithium along with boron. After boron is extracted, lithium remains in the waste, which has a carbonate‐hosted clay‐type structure, along with other impurities. The scarcity of lithium resources and the increasing need for lithium worldwide make such resources economically important. Although the best hydrometallurgical method for the recovery of lithium trapped within the clay‐structured mineral resources is roasting with chemicals to disrupt the clay structure and acid leaching, the process is quite difficult and costly due to the high energy and chemical addition requirements. To overcome this challenge, this study proposed a high‐temperature–pressure sulphuric acid leaching process to recover lithium from the boron waste. Under the optimized conditions (liquid/solid ratio: 10, acid concentration: 1 M, temperature: 150°C, and contact time: 120 min), 100% of lithium was leached. The leaching mechanism was determined through mineral characterization (X‐ray diffractometry [XRD], X‐ray fluorescence spectrophotometer [XRF], scanning electron microscopy–energy‐dispersive X‐ray spectroscopy [SEM–EDX], Mastersizer), and a shrinking core heterogeneous kinetics model. It was found that high‐temperature–pressure sulphuric acid leaching disrupted clay structure and promoted the leaching of lithium, the leaching kinetics fit the shrinking core heterogeneous kinetics model, and was controlled by a dual mechanism with ash diffusion and chemical reactions on the particle surface. The reaction rate constants increased with increasing temperature, and the activation energy was found to be 32.17 kJ/mol.

You say potato, I say vegetable; you say tomato, I say fruit: Cognitive validity of food group-based dietary recall questions

BackgroundThere is a need for valid, standardized approach for list-based questionnaires to measure food group consumption for indicators of diet quality including dietary diversity. ObjectiveA common method for collecting dietary diversity data consists of open-ended food group questions, e.g. Yesterday, did you eat any vegetables, such as cucumber, cabbage, or celery? We sought to examine the cognitive validity of open-ended questions that require respondents to categorize foods, and closed-ended alternatives using sentinel foods. MethodsPretesting and 83 cognitive interviews were conducted in five languages in São Paulo and New York City in 2018. In structured interviews, respondents were asked to describe their thought processes in answering each question. Their feedback and responses to closed-ended and open-ended food group questions were compared. The Gallup World Poll then piloted two versions of the questionnaire in a nationally representative sample of 1,000 in Brazil in 2018. ResultsRespondents in all settings miscategorized foods when asked open-ended food group questions (0-82%, depending on the food group), respondents varied in their ability to think of other foods that belonged to specified food groups (35-50% could think of any items), and open-ended questions presented an additional cognitive burden. There were no significant differences between the results from closed-ended and open-ended questions in the national pilot test. In the context of a multi-topic survey, the finalized questionnaire took 3-5 minutes, had no additional training requirements, and enumerators reported similar ease in administration as other survey modules. ConclusionsFor data collection on food group consumption, open-ended questions requiring respondents to categorize foods present cognitive validity problems. Closed-ended questions using sentinel foods reduce or eliminate ambiguity, presenting lower cognitive burden and greater comprehension. Based on these results, the closed-ended method has been adopted in international survey platforms for measuring dietary diversity and other aspects of diet quality.

Pulse current stabilizer with digital control for the power supply system of the plasmatron

Purpose. Solution of theoretical and practical problems on providing digital control of a pulse converter using high-speed microprocessor tools in the output current stabilization mode with provision of a specified duration of transient processes caused by an increase in load voltage and output current astaticity, which allows to obtain significant advantages over analog versions. Methodology. Review of literary and patent sources on the subject, theory of pulse automatic control systems, mathematical modeling of processes in pulse current stabilizers in the MATLAB / Simulink software environment and physical prototyping. Findings. A simulation model of an autonomous power supply system based on a converter using soft switching technology of transistors and an arc load is presented. A control law is synthesized and a model of a pulse current stabilizer is developed. A method is proposed and ways are found to control a pulse current stabilizer that provide a given duration of transients and astatism of the output current. A model of a pulse stabilizer with digital control based on a single-crystal computing module is developed and manufactured. The results of the study confirm the achievement of a finite duration of transient processes caused by a step change in the load voltage, close to 3-4 periods of conversion and output current astaticism. It is shown that the use of a pulse stabilizer using a fully digital control circuit has undeniable advantages over analog systems. Originality. The problem of synthesizing a digital controller for a given control time by the method of desired transfer functions for a soft switching operating converter on an arc load is solved. In addition to the given control time, additional quality requirements in the steady state are provided. Practical value.The use of microprocessor technology makes it possible not only to implement complex and new highly efficient control algorithms for a converter operating in the pulse current stabilizer mode, but also to perform additional functions for overload protection, self-diagnostics and telemetry of pulse converters. The use of this same digital device simultaneously for the purpose of controlling a pulse converter will allow to abandon analog PWM controllers and thereby reduce its own energy consumption and weight and size characteristics, increase the reliability of the functioning of pulse converters in power supply systems as a whole.

Is blockchain cost-effective in construction project management? A systematic review from the perspective of transaction cost

PurposeBlockchain technology (BCT) is considered a promising tool to improve the productivity of construction project management. Existing research has studied its potential costs and benefits for the construction industry. However, the potential costs and benefits of BCT failed to be compared as actual costs and benefits of specific applications for stakeholders. To fill this gap, this study seeks to analyze the cost-effectiveness of BCT-based applications in construction project management.Design/methodology/approachThis study is conducted with a customized systematic literature review based on transaction cost theory to enable qualitative comparison. With a deliberately designed structure confining extraneous variables, the costs and benefits of BCT-based applications are identified and compared. The inherent dependent relations of processes and the evolution relations of functions are identified. The cost-effectiveness of blockchain adoption is then analyzed.FindingsSeven functions and six challenges are identified within five processes. The result suggests all identified functions are cost-effective except for manual instruction (coding smart contracts manually). The smart contracts require explicit definition and logic to be effective. However, the construction projects essentially require the institution to be flexible due to unpredictability. The adoption of smart contracts and corresponding additional requirements can increase the transaction cost of bounded rationality.Research limitations/implicationsAs manual instruction is fundamental to realize other functions, and its advanced substitute relies on its broad adoption, its cost-effectiveness must be improved for applications to be acceptable to stakeholders. The establishment of a universal smart contract model and a universal, legitimate and efficient database structure are recommended to minimize the cost and maximize the effect of applications.Originality/valueThis study contributes to the knowledge by providing a comprehensive analysis of BCT adoption’s cost-effectiveness in construction project management. The adopted review structure can be extended to analyze the qualitative benefits and challenges of management automation in the early stages.

What challenges exist within the child welfare system in meeting the health needs of children in care?

Abstract From society’s perspective, the goal of societal care is to protect disadvantaged children and provide them with improved opportunities. In the realm of social care, the child welfare system takes the place of parental responsibilities to safeguard children’s well-being and developmental needs, including their health. However, while holding child welfare agencies responsible, national legislation often lacks specific methods for fulfilling this mandate. Over the years, evidence has shown that limited health care access and unmet health needs often endure in care. In Sweden, efforts to address the issue include mandatory health assessments upon entry into care and collaborative agreements between social services and health care sectors. However, recent studies reveal that only one-third of children undergo these assessment, and collaborative agreements remain lacking in many local authorities. This suggests that additional legal requirements do not offer a straightforward solution. Dr Forsman, with a background in social work, will discuss the child welfare system’s responsibilities and the traditional reliance on social workers and foster carers to address health needs and coordinate care. What are the underlying barriers to successful advocacy and comprehensive health care coordination within the child welfare system? How can the system better respond to the health needs of children in care?

Drone-based warehouse inventory management of perishables

Warehouse inventory management is a complex process. When inventory includes perishables, the complexity of these processes is compounded with additional requirements such as appropriate ambient storage conditions and placement of one type of perishables (e.g., bananas) far away from another type of perishables (e.g., strawberries). With perishables spending a significant amount of time post-harvest in warehouses, appropriate management of warehouse inventory is necessary to reduce wastage due to spoilage. Drone-based warehouse inventory management is gaining popularity as seen in the increasing number of firms in this space as well as the number of research publications. RFID tags have been widely used for inventory management for more than two decades. While drones have been successfully used in warehouses with non-perishables, RFID and drone use in warehouses with perishables has not witnessed its fair share as evidenced by the lack of publications in this general area. This paper is a step in the direction to address this void in published literature. We consider object-level RFID tags and drones to automate warehouse inventory management of perishables. Results from our analytical model and simulation analysis indicate that such warehouse automation is beneficial to both the warehouse operators and their customers.

DSHEA 1994 – Celebrating 30 Years of Dietary Supplement Regulation in the United States

The Dietary Supplement Health and Education Act (DSHEA) of 1994 defined the FDA’s statutory authority to regulate dietary supplement products as a category of food in the United States. As we celebrate 30 years post-DSHEA, it is important to reflect on its significance for public health, influence on the continuously evolving and expanding product category, the current regulatory framework, and potential opportunities or modernizing oversight to ensure a strong and well-regulated marketplace. An estimated three-fourths of U.S. consumers report use of dietary supplements, and the product market has grown substantially since the passage of DSHEA, from approximately 4,000 products in 1994 to 80,000+ present day. This growth represents a current $60 billion domestic and $200 billion international market for dietary supplements. Scientists, public health officials, health care providers, patients, consumer advocacy organizations, and the U.S. Food and Drug Administration have all called for reform to what has been described as ‘outdated’ regulation of dietary supplements. Advancing at an even faster rate is published scientific evidence in the space. This special issue of the Journal of Dietary Supplements comprises a collection of articles authored by academicians, legal scholars, representatives of U.S. government agencies, and industry scientists that critically examine the successes, challenges, and opportunities for improving specific aspects of DSHEA and domestic health policy. This editorial provides historical context and milestones of dietary supplement regulation in the U.S. post-DSHEA and offers an overview of the research contained within the special issue. Advancing toward a more transparent and safer marketplace requires trustworthy supply chains, increased adherence to quality standards, additional labeling requirements, and enhancement of post-market surveillance. This special issue seeks to contribute to the broader understanding of dietary supplement regulation and its future direction.

ГНОСЕОЛОГІЯ УПРАВЛІННЯ ТРУДОВИМ ПОТЕНЦІАЛОМ ПІДПРИЄМСТВ В УМОВАХ НЕВИЗНАЧЕНОСТІ

The existence of conditions of uncertainty in the process of managing the labor potential of enterprises gives rise to the need to find optimal management methods and tools for ensuring and combining the available human resources, their knowledge, experience and qualifications with the main components of the enterprise's potential, he strategy and goals of its development, ensuring the company's need for employees with the necessary qualifications and effective use of the labor potential of both individual employees and the team as a whole. A research aim is to learn the process of managing the labor potential, based on the current conditions of uncertainty in the development of enterprises. The object of the research is the process of managing the labor potential of enterprises in different economic conditions. The method of the research are modern methods and technologies of scientific knowledge, methods and techniques of conducting scientific research, tools of systemic, complex, economic analysis, principles of management of enterprises and their labor resources, which allow to review the existing approaches to the management of labor potential and identify directions stabilization of enterprises in modern economic conditions. The hypothesis of the research was an assumption about the possibility to determine the logic of learning the process of managing the labor potential of enterprises in modern conditions of uncertainty. The statement of basic materials. It is proved that epistemology is applied in the research in a purposeful way, as it is a tool of knowledge and a philosophy of managing the labor potential of enterprises in conditions of uncertainty. It has been confirmed that the management of labor potential is a component of the general process of managing the production potential of the enterprise, which means that it makes a direct contribution to the results of operations, the volume and output of products, the creation of certain benefits not only by the economic entity itself, but also contributes to the national income of the country. A certain philosophy of labor potential management is proposed, aimed at developing a special toolkit and acquiring new knowledge that can be used in labor potential management programs in wartime and postwar times. The originality and practical significance of the research is confirmed by the above philosophy of managing the labor potential of enterprises in modern conditions of uncertainty. Conclusions and perspectives of further research. The implemented epistemology of labor potential management made it possible to state that labor potential is a complex system with certain properties that requires the formation of additional requirements both for the assessment of labor potential and for its management. Therefore, the formation of an effective philosophy of labor potential management requires the constant development of personnel, the development of special programs for the management of labor potential based on the existing conditions of uncertainty of enterprises, including war and post-war times. Further research will be aimed at the development of special labor potential management programs, based on the sphere of activity of enterprises and their regional location

Popliteal plexus block compared with tibial nerve block on rehabilitation goals following total knee arthroplasty: a randomized non-inferiority trial

This trial examined the effectiveness of the popliteal plexus block (PPB) and tibial nerve block (TNB) for early rehabilitation after total knee arthroplasty (TKA). We allocated 136 participants to receive PPB or TNB with 0.25% levobupivacaine 10 mL in a randomized, double-masked manner. The primary outcome was achieving rehabilitation goals with a non-inferiority 9-hour margin, including adequate pain relief, knee flexion angles over 90 degrees, and enabling ambulatory rehabilitation. The time to reach rehabilitation goals showed non-inferiority with 49.7 ± 10.5 h for TNB and 47.4 ± 9.7 h for PPB, whose mean difference (PPB - TNB) was − 2.3 h (95% CI -5.8 to 1.2 h; P < 0.001). PPB showed higher dorsal and plantar percentage of maximum voluntary isometric contraction (dorsal, PPB 87.7% ± 11.4% vs. TNB 74.0% ± 16.5%: P < 0.001; plantar, PPB 90.9% ± 10.3% vs. TNB 72.1% ± 16.0%; P < 0.001) at six hours after nerve block. No significant differences between the two groups emerged in pain scores, knee range of motion, additional analgesic requirements, success in the straight leg raise, and adverse events. PPB exhibited non-inferiority to TNB in achieving postoperative rehabilitation goals and had superiority in preserving foot motor strength after TKA. (200)

Downwind and upwind approximations for primal and dual problems of elasto-plasticity with Prandtl–Reuss type material laws

Modern adaptive finite element (FE) algorithms for solution of initial-boundary-value-problems (IBVP) employ goal-oriented error measures in order to assess the quality of computational results for the physical event under investigation. However, traditional time-stepping algorithms for solution of the corresponding dual problem run backwards-in-time, which due to additional storage requirements might become a serious drawback when an extensive number of time steps for the FEM simulation arises. In this paper, we take advantage of an end-boundary-value-problem (EBVP) associated to IBVP, with corresponding dual-problem running forwards in time. In order to obtain a unified framework for numerical approximation of primal and dual weak forms for both, IBVP and EBVP, respectively, we apply the concept of downwind and upwind approximations not only to the trial functions but also to the test functions. This results into eight different integration schemes. On this basis, as a main result of this contribution, a time-stepping algorithm is obtained, which runs forwards-in-time for the dual problem and therefore avoids the additional storage requirements of the traditional backwards-in-time stepping procedures. The presented algorithm is numerically tested and validated for a CT-specimen for elastic and elasto-plastic behavior, where the constitutive equations are written in Prandtl–Reuss type format.

Impact of low-pressure pneumoperitoneum and deep neuromuscular blockade on surgeon satisfaction and patient outcomes in laparoscopic cholecystectomy patients: A prospective randomised controlled study.

The impact of laparoscopic surgery on homeostatic systems necessitates careful consideration of intra-abdominal pressure (IAP) management. This study investigated the effects of low-pressure pneumoperitoneum with deep neuromuscular blockade (NMB) on surgeon satisfaction, haemodynamics and post-operative outcomes in laparoscopic cholecystectomy patients. The study design involves prospective randomised control. Ninety patients were assigned to low (7-10 mmHg, n = 45) or normal (12-16 mmHg, n = 45) IAP groups. Deep NMB, guided by train-of-four monitoring, was administered. This study evaluated surgical rating scale scores, haemodynamics and post-operative outcomes through a literature review. A computer programme (IBM, SPSS) was used for statistical analysis. Chi-square and Mann-Whitney U tests were used to analyse patients' IAP levels, additional NMB requirements, surgical rating scale scores and numerical rating scales. Patient demographics and other intraoperative and post-operative variables were analysed with Student's t-test and the Mann-Whitney U test. Values of P < 0.05 were considered to indicate statistical significance. No significant demographic differences were observed. The low-pressure group exhibited lower post-operative pain (P < 0.01) and reduced analgesia requirements (P = 0.00). On analysis of the surgeon rating scale, no disparities were evident between the groups. NMB usage correlated with height and weight (P < 0.01). Heart rate showed no intergroup differences. The MAP measured after 15 min was lower in Group L, and the difference was significant (P = 0.023). The SAP measured after 30 min was lower in Group L, and the difference was significant (P = 0.017). Blood gas values and surgical field visibility were unaffected by the IAP. The positive correlations between NMB, height and weight aligned with previous research. This study highlights successful laparoscopic cholecystectomy under low IAP, deep NMB and favourable post-operative outcomes. Despite these limitations, the findings contribute to optimising laparoscopic surgical approaches.

Clinical Outcomes of a Minimally Invasive Percutaneous Brostrom Technique without Arthroscopic Assistance.

Surgical management of chronic lateral ankle instability has traditionally been performed using an open technique. Arthroscopic-assisted and all-arthroscopic techniques have gained popularity as they have achieved strong clinical outcomes. However, they rely on the surgeon's arthroscopic skills and familiarity with arthroscopic anatomy. Recently, a minimally invasive percutaneous technique without arthroscopic assistance has been developed that incorporates the benefits of arthroscopy, such as minimal soft tissue disruption, without the additional requirements of performing an arthroscopic technique. The aim of the current study is to describe the minimally invasive percutaneous technique for chronic lateral ankle instability and report on its clinical outcomes. Fifty-four consecutive patients without intra-articular ankle pathology underwent lateral ligament repair for chronic ankle instability with a percutaneous technique at a single institution by a fellowship-trained foot and ankle surgeon. Foot Function Index (FFI) score was recorded pre-operatively and post-operatively at final follow-up. All patients had a minimum follow-up of 12 months. Post-operative complications and patient satisfaction were also recorded. A significant improvement (p < 0.001) in FFI compared to pre-operative values (from 55, SD 4.1, to 10, SD 1.9) was observed. A single patient required a return to the operating room for open revision with allograft reconstruction following a fall 2.5 months post-operatively. There were no other complications including infection or nerve injury. The overall rate of satisfaction after surgery was 98.1%, with one patient dissatisfied due to excessive ankle stiffness. The described minimally invasive percutaneous Brostrom procedure is safe and effective for the treatment of chronic lateral ankle instability without intra-articular ankle pathology.

Consideration of factors of low accrual and methods for setting appropriate accrual periods: Japan Clinical Oncology Group study

BackgroundPoor patient accrual can delay reporting of clinical trials and, consequently, the development of new treatments. For reducing the risk of additional resource requirements, a method for setting planned accrual periods with minimal deviation from the actual accrual periods is desirable. Risk factors for poor patient accrual and the appropriate method of estimating the required accrual period for timely completion of clinical trials were evaluated using the data of trials conducted by the Japan Clinical Oncology Group.MethodsThe study included 199 trials that started patient accrual between January 1, 1990, and June 30, 2021. The explanatory variables included factors that could be evaluated prior to trial commencement. We also evaluated whether the estimation methods for accrual pace could lead to completion within the planned accrual period.ResultsApproximately 23.6% of trials were completed within the planned accrual period. The risk factors for trial extension included planned accrual periods > 3 years (reference group: ≤ 3 years, odds ratio [OR] 0.37, 95% confidence interval [CI]: 0.15–0.92, P = 0.033) and stratified trial design (reference group: nonrandomized phase II trials, nonrandomized phase III trial [OR: 3.28, 95% CI: 0.99–10.9, P = 0.051], randomized phase II trial [OR: 3.91, 95% CI: 0.75–20.30, P = 0.105], and randomized phase III trial [OR: 9.29, 95% CI: 3.39–25.40, P < 0.001]). The method of estimating the accrual pace based on past clinical trials facilitated timely completion of the trial (OR: 3.51; 95% CI: 1.73–7.10, P < 0.001), unlike the estimation method based on survey evaluation of the accrual pace for participating institutions (OR: 1.12, 95% CI: 0.56–2.26, P = 0.751). Furthermore, the discrepancy between planned and actual accrual periods was minimal when using the methods of considering the accrual pace of past clinical trials.ConclusionsConsidering the accrual pace of past clinical trials is useful for estimating the required accrual period if data from past trials are available. When conducting a survey, it is necessary to be cautious of overestimating the cases at each facility.

Turbopump Parametric Modelling and Reliability Assessment for Reusable Rocket Engine Applications

The development of modern reusable launchers, such as the Themis project with its LOX/LCH4 Prometheus engine, CALLISTO—a reusable VTVL-launcher first-stage demonstrator with a LOX/LH2 RSR2 engine, and SpaceX’s Falcon 9 with its Merlin 1D engine, underscores the need for advanced control algorithms to ensure reliable engine operation. The multi-restart capability of these engines imposes additional requirements for throttling, necessitating an extended controller-validity domain to safely achieve low thrust levels across various operating regimes. This capability also increases the risk of component failure, especially as engine parameters evolve with mission profiles. To address this, our study evaluates the dynamic reliability of reusable rocket engines (RREs) and their subcomponents under different failure modes using multi-physics system-level modelling and simulation, with a particular focus on turbopump components. Transient condition modelling and performance analysis, conducted using EcosimPro-ESPSS software (version 6.4.34), revealed that turbopump components maintain high reliability under nominal conditions, with turbine blades demonstrating significant fatigue life even under varying thermal and mechanical loads. Additionally, the proposed predictive model estimates the remaining useful life of critical components, offering valuable insights for improving the longevity and reliability of turbopumps in reusable rocket engines. This study employs deterministic, thermally dependent structural simulations, with key control objectives including end-state tracking of combustion chamber pressure and mixture ratios and the verification of operational constraints, exemplified by the LUMEN demonstrator engine and the LE-5B-2 engine class.

Design of concatenative complete complementary codes for CCC-CDMA via specific sequences and extended Boolean functions

A complete complementary code (CCC) consists of M sequence sets with size M. The sum of the auto-correlation functions of each sequence set is an impulse function, and the sum of cross-correlation functions of the different sequence sets is equal to zero. Thanks to their excellent correlation, CCCs received extensive use in engineering. In addition, they are strongly connected to orthogonal matrices. In some application scenarios, additional requirements are made for CCCs, such as recently proposed for concatenative CCC (CCCC) division multiple access (CCC-CDMA) technologies. In fact, CCCCs are a special kind of CCCs which requires that each sequence set in CCC be concatenated to form a zero-correlation-zone (ZCZ) sequence set. However, this requirement is challenging, and the literature is thin since there is only one construction in this context. We propose to go beyond the literature through this contribution to reduce the gap between their interest and our limited knowledge of CCCCs. This paper will employ novel methods for designing CCCCs and precisely derive two constructions of these objects. The first is based on perfect cross Z-complementary pair and Hadamard matrices, and the second relies on extended Boolean functions. Specifically, we highlight that optimal and asymptotic optimal CCCCs could be obtained through the proposed constructions. Besides, we shall present a comparison analysis with former structures in the literature and examples to illustrate our main results.

Towards Integrated Safety Assurance Methodology for Autonomous Vessel Navigation Systems

Abstract Safety assurance remains paramount for the realization of autonomous vessels. A robust assurance methodology that can provide traceability throughout the design and verification process is necessary to demonstrate safety equivalence to that of conventional ships. However, there are few references that propose a holistic safety assurance scheme for autonomous ships, using actual engineering processes of ships as examples. This study proposes a design and development method for an autonomous navigation system that integrates Model-Based Systems Engineering (MBSE), System Theoretic Process Analysis (STPA), Failure Modes and Effects Analysis (FMEA), and several verification methods including simulation-based tests to develop a comprehensive safety assurance scheme. This safety assurance scheme is being conducted as a case study for a newly constructed autonomous vessel. First, STPA can be performed on the conceptual design established by MBSE to extract additional safety requirements from the identified loss scenarios. Focusing on the process model in the loss scenario description leads to a deeper understanding of the system behavior. FMEA in addition identify potential component failure modes and their impact on system safety. The multi-level requirements that emerge from these activities are validated in test scenarios. Simulators are used to evaluate whether the autonomous navigation system’s safety can meet predefined pass criteria in some of the scenarios. These activities ensure traceability from safety goals to design decisions, allowing design changes and their impact on safety to be evaluated throughout the development lifecycle and allowing for more systematic ongoing monitoring during operations.

Comparison of the Analgesic Effect of Erector Spinae Plane Block Versus Caudal Epidural Block Following Unilateral Pediatric Inguinal Hernia Surgery: A Prospective, Randomized Study

Background: Caudal epidural block (CEB) has long been used as a standard method for pain control in pediatric surgery. Erector spinae plane block (ESPB) is a newer technique that has attracted attention for its potential to provide analgesia in children. Aim: The aim of this study was to compare and evaluate the effectiveness of ESPB and caudal block on postoperative pain in pediatric patients who underwent unilateral inguinal hernia surgery. Methods: This prospective, randomized trial was conducted with a total of 60 pediatric patients, aged 1–8 years, in the ASA I–II group. The patients were randomly divided into two groups as Group CEB (n = 30), and Group ESPB (n = 30). In the caudal block group, 0.25% bupivacaine 0.5 ml/kg (max 20 ml) was administered in the caudal space, while in the ESPB block group, the block was performed with 0.5 ml/kg 0.25% (max 20 ml) bupivacaine at the L1 vertebral level. Face, legs, activity, cry, and consolability (FLACC) scores were recorded postoperatively at 1, 2, 4, 6, 12, and 24th hours. The first analgesic requirements and time for rescue analgesia were also recorded. Results: While no significant difference was noticed between the two groups’ FLACC scores at the zeroth hour, first hour, second hour, fourth hour, and sixth hour (i.e. postoperatively [P &gt; 0.05]), the FLACC scores of 12th hour in the ESPB group were significantly lower than the caudal block group (P &lt; 0.05). There was also no significant difference in intraoperative additional analgesia requirements between the groups (P &gt; 0.05). The time to first postoperative analgesia in the ESPB group was higher than that in the caudal block group (P &lt; 0.05). Conclusion: The ESPB provided superior postoperative analgesia to the CEB in pediatric patients undergoing inguinal hernia surgery, and ESPB can be used as a relatively safer postoperative multimodal analgesia approach as an alternative to CEB.

Evaluating Environmental Impact and the Significance of Shipboard Carbon Capture and Storage for Emission Reduction in Maritime Sector

Abstract This study conducts Life Cycle Assessment (LCA) to evaluate the environmental impacts of Shipboard Carbon Capture &amp; Storage (SCCS) across its entire lifecycle. It examines the full-spectrum carbon capture and storage effects from well-to-tank and tank-to-propeller for four types of marine fuels: Very Low Sulphur Fuel Oil (VLSFO), Marine Gas Oil (MGO), Liquefied Natural Gas (LNG), and Methanol. Additionally, the study examines the Energy Efficiency Existing Ship Index (EEXI) and Carbon Intensity Indicator (CII) of a current ocean-going container ship to quantify the potential benefits of SCCS in reducing ship carbon emissions. The results indicate that the application of SCCS can significantly reduce emissions from carbon-based fuels during ship operations. In particular, ships using VLSFO as fuel can achieve 61.0% reduction in emissions by installing SCCS. However, the application of SCCS leads to 7.8% increase in fuel consumption due to additional energy requirement. In addition, this study also found while fossil methanol reduces emissions during ship combustion, its life cycle emissions are 17.5%-19.6% higher than conventional fossil fuel due to production emissions. The overall SCCS has a positive impact on emission reduction for ships and is reflected in the improvements in EEXI and CII. With the implementation of SCCS, ships fuelled by VLSFO and MGO can remain compliant with IMO Greenhouse Gases emission strategy until 2030. For ships fuelled by LNG and Methanol, compliance can remain beyond 2030.

Highly enhanced fluoride removal from aqueous systems via solvent extraction utilizing trialkyl phosphine oxide as an efficient extractant

Solvent extraction (SX) has been recognized as an efficient approach for the large-scale removal of impurities, demonstrating considerable potential for fluoride extraction in industrial applications. However, existing fluoride extraction methods typically require the incorporation of additives to form complexes with fluoride for its removal. Due to the excessive additive requirements for efficient fluoride removal, these methods inevitably result in secondary contamination of feed solution, necessitating additional purification efforts to remove them. In this study, four extractants (trioctyl amine, tributyl phosphate, trioctyl phosphate, and trialkyl phosphine oxide (TRPO)) were investigated for fluoride removal via hydrogen bonding with hydrofluoric acid (HF). Various parameters, including the concentrations of extractants and stripping agents, pH values, extraction time, and temperature were initially optimized. It was found that TRPO exhibits the highest extraction efficiency for HF, with a single-stage extraction rate exceeding 70 %. Complete fluoride removal (> 99.9 %) was achieved through a consecutive four-stage extraction process. Further experiments, including maximum loading and slope analysis, combined with FT-IR and 19F NMR characterization, and DFT calculations elucidate the mechanism of the extraction. The transfer of HF into the organic phase is accomplished by the formation of a 1:1 hydrogen-bonded complex with TRPO. The loaded fluoride in the organic phase can be easily stripped by a base to get a fluoride salt. This study paves the way for the construction of novel SX systems to remove fluoride as HF.

Topology‐preserving phase‐field modeling of elastic bending energy

AbstractIn vesicle membranes, the minimum of the elastic bending energy determines the equilibrium shape. We can reformulate the energy using a phase‐field function and optimize it using the standard gradient flow approach. The method, in its typical formulation, allows topological changes in the membrane; however, in certain events, like in the simulation of blood cells, maintaining the initial topology of the membrane is crucial. In this study, we add a constraint on the phase‐field method to preserve the topology. We note that even if the phase‐field method is formulated using a hyperbolic tangent function, during a change in topology, the membrane's profile deviates from the tanh function. Owing to this idea, the constraint imposes an additional requirement on the profile to maintain the tanh shape, thus preserving the topology. We perform extensive experiments in two‐dimensional and three‐dimensional scenarios to demonstrate that our method preserves the topology during the simulation.