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To maintain high-quality semiconductor wafer production processes, it is necessary to build high-quality virtual metrology (VM) model. Based on the result of the VM, the engineer can monitor and control the specific process. In the manufacturing process, various sources are obtained from sensor equipment. It is important to consider that these source data exhibit varying characteristics during the model construction. However, when all data sources are simply aggregated into a single model, the performance of the overall model may degrade, especially if any of the individual sources contain outliers or noise. To address this issue, we develop a data-fusion model designed to incorporate diverse data sources into a unified multi-source model. In particular, we improve an Adaboost regression algorithm to make it suitable for multi-source data in the field of VM. The algorithm combines the residuals of the models derived from each individual data source and all sources to adaptively adjust the thresholding value, which, in turn, determines whether the predicted values are accurate or not for each weak learner. Extensive practical validations on real-world processing data from semiconductor manufacturers have demonstrated that the proposed method outperforms single learning algorithms and is more robust than all benchmarks. [ABSTRACT FROM AUTHOR]

We present a general and practical theoretical framework to investigate how energy is dissipated in open quantum system dynamics. This is performed by quantifying the contributions of individual bath components to the overall dissipation of the system. The framework is based on the Nakajima–Zwanzig projection operator technique, which allows us to express the rate of energy dissipation into a specific bath degree of freedom by using traces of operator products. The approach captures system-bath interactions to all orders, but is based on second-order perturbation theory on the off-diagonal subsystem's couplings and a Markovian description of the bath. The usefulness of our theory is demonstrated by applying it to various models of open quantum systems involving harmonic oscillators or spin baths and connecting the outcomes to existing results such as our previously reported formula derived for locally coupled harmonic baths [Kim and Franco, J. Chem. Phys. 154, 084109 (2021)]. We also prove that the dissipation calculated by our theory rigorously satisfies thermodynamic principles such as energy conservation and detailed balance. Overall, the strategy can be used to develop the theory and simulation of dissipation pathways to interpret and engineer the dynamics of open quantum systems. [ABSTRACT FROM AUTHOR]

Through an ethnographic study of a manufacturing monitoring technology, the author examines how the relations among workers, managers, and third-party technologists impact the ongoing configuration of cloud-based workplace technologies. Because these technologies are broadly networked, data-driven, and highly malleable, the author argues that technologists have an increasingly prominent role. By tracing issues raised by workers and managers in the focal customer firm, the study shows that the employment relation can explain only a limited set of outcomes. An analysis that accounts for technologists' innovative and economic relations with their users fully explains which issues are resolved and how. In contrast to research that implies technologists amplify institutionalized patterns of labor–management relations through their design choices, this study shows that technologists are complex organizational actors with situated interests, values, and identities. Through the development of a triadic model of relations, the author demonstrates why technologists must be included in analyses of contemporary technologies. [ABSTRACT FROM AUTHOR]

Background: Out-of-school time (OST) science, technology, engineering, and math (STEM) programming has positive impacts for youth, and the importance of engineering design activities and principles within STEM programming is well-supported by research. Including subject matter experts (SMEs) in these programs enriches the experience of youth participants. Public libraries are widely accessible to the public, and their role in the OST arena is expanding. Library staff can boost the quality of STEM learning experiences by partnering with SMEs. Purpose: Subject matter experts (SME) contribute more than just their expertise. Between 2018 and 2019, a group of diverse professional engineers and librarians co-facilitated engineering activities at six U.S. libraries serving traditionally underserved populations. This study investigates the alignment in active learning preferences between youth, library staff, and professional engineer volunteers. Method: The study's design implemented the Framework for the Observation and Categorization of Instructional Strategies (FOCIS), which identifies seven different types of learning activities: collaborating, competing, performing, discovering, making, teaching, and caretaking. The FOCIS helped researchers evaluate the learning activity preferences of youth participants, engineers, and librarians. Results: The analysis showed that the learning activity preferences of youth and engineers were much more closely aligned than those of librarians. Conclusions: Alignment between youth-program participants and SME program facilitators has the potential to enrich the program experience and foster active engagement. [ABSTRACT FROM AUTHOR]

Cost engineering capabilities are becoming increasingly important for the competitiveness of industrial firms, especially for engineer to order products (ETOPs). Despite this relevance, the literature on the use of advanced data-driven methodologies, such as machine learning (ML), for early cost estimation (CE) of ETOPs is quite sparse. Furthermore, ML has still seen little use in real industrial applications due to several challenges. Accordingly, the objective of this paper is threefold: (a) to develop a solid early CE approach for ETOPs, including feature selection; (b) to investigate the benefits of adopting ML for ETOPs' CE; (c) to identify how ML can be introduced into real industrial context with little knowledge on ML. Long action research has been carried out with a large industrial company that produces Oil & Gas ETOPs. We observed how ML facilitates the exploration of the relationships between the choices of early design stages and the CE. ML algorithms also allowed to both capture the high variability of the data and test different combinations of cost drivers in very effective ways. The project resulted in an accurate CE framework with an iterative feature selection process and an approach for introducing ML into a real industrial context. [ABSTRACT FROM AUTHOR]

Ecosystem engineers alter habitat and resource availability within ecosystems, but the magnitude of these effects depends on abiotic context and spatial scale. We examined how the effects of freshwater mussels, an ecosystem engineer, changed with spatial scale. We combined a field enclosure experiment and comparative field study to evaluate associations among mussels and macroinvertebrate communities across three spatial scales: mussel individuals (~ 0.01 m2), patches of mussels (0.25 m2), and large aggregations of many mussel patches (mussel beds, ~ 1000 m2). We used canonical correspondence analysis and variation partitioning to evaluate how mussel abundance, food availability, substrate heterogeneity, and flow influenced macroinvertebrate communities. We found that mussels' influence on macroinvertebrate communities differed among spatial scales. At the smallest scale, macroinvertebrate density increased on the shells of live mussels, likely due to mussel influences on food availability to grazers. At the patch scale, we found no mussel effects, likely because they were overridden by a flood event. At the mussel bed scale, macroinvertebrate communities were primarily controlled by flow and secondarily by food availability. As such, the continued loss of freshwater mussels means the loss of habitat creation and food provisioning for other aquatic groups, and alteration of facilitation landscapes within streams. [ABSTRACT FROM AUTHOR]

Background: Mesenchymal stromal cell (MSC) therapy holds great potential yet efficacy and safety concerns with cell therapy persist. The beneficial effects of MSCs are often attributed to their secretome that includes extracellular vesicles (EVs). EVs carry biologically active molecules, protected by a lipid bilayer. However, several barriers hinder large-scale MSC EV production. A serum-free culturing approach is preferred for producing clinical-grade MSC-derived EVs but this can affect both yield and purity. Consequently, new strategies have been explored, including genetically engineering MSCs to alter EV compositions to enhance potency, increase circulation time or mediate targeting. However, efficient transfection of MSCs is challenging. Typical sources of MSC include adipose tissue and bone marrow, which both require invasive extraction procedures. Here, we investigate the use of urine-derived stem cells (USCs) as a non-invasive and inexhaustible source of MSCs for EV production. Methods: We isolated, expanded, and characterized urine-derived stem cells (USCs) harvested from eight healthy donors at three different time points during the day. We evaluated the number of clones per urination, proliferation capacity and conducted flow cytometry to establish expression of surface markers. EVs were produced in chemically defined media and characterized. PEI/DNA transfection was used to genetically engineer USCs using transposon technology. Results: There were no differences between time points for clone number, doubling time or viability. USCs showed immunophenotypic characteristics of MSCs, such as expression of CD73, CD90 and CD105, with no difference at the assessed time points, however, male donors had reduced CD73 + cells. Expanded USCs were incubated without growth factors or serum for 72 h without a loss in viability and EVs were isolated. USCs were transfected with high efficiency and after 10 days of selection, pure engineered cell cultures were established. Conclusions: Isolation and expansion of MSCs from urine is non-invasive, robust, and without apparent sex-related differences. The sampling time point did not affect any measured markers or USC isolation potential. USCs offer an attractive production platform for EVs, both native and engineered. [ABSTRACT FROM AUTHOR]

Introduction: Medical phantoms play a crucial role in medical imaging and therapy. However, the successful development of these phantoms heavily relies on a comprehensive understanding of the requirements specific to each application. Methods: In this paper, we emphasize the significance of requirement analysis in medical phantom development and develop a novel approach for gathering and classifying requirements specific for phantom development. Results: The implemented survey tool is designed to accommodate the diverse needs of stakeholders involved in phantom development, including medical staff, physicists, engineers, and product developers. To validate the effectiveness of the approach, we conduct the development of a multimodal deformable pelvic phantom, providing insights into the process and its applicability. Discussion: The results demonstrate the utility and reliability of our approach in systematically gathering, categorizing, and prioritizing requirements, thus facilitating the streamlined and efficient development of medical phantoms. [ABSTRACT FROM AUTHOR]

High-harmonic generation (HHG) has emerged as a central technique in attosecond science and strong-field physics, providing a tool for investigating ultrafast dynamics. However, the microscopic mechanism of HHG in solids is still under debate, and it is unclear how it is modified in the ubiquitous presence of phonons. Here we theoretically investigate the role of collectively coherent vibrations in HHG in a wide range of solids (e.g., hBN, graphite, 2H-MoS2, and diamond). We predict that phonon-assisted high harmonic yields can be significantly enhanced, compared to the phonon-free case – up to a factor of ~20 for a transverse optical phonon in bulk hBN. We also show that the emitted harmonics strongly depend on the character of the pumped vibrational modes. Through state-of-the-art ab initio calculations, we elucidate the physical origin of the HHG yield enhancement – phonon-assisted photoinduced carrier doping, which plays a paramount role in both intraband and interband electron dynamics. Our research illuminates a clear pathway toward comprehending phonon-mediated nonlinear optical processes within materials, offering a powerful tool to deliberately engineer and govern solid-state high harmonics. [ABSTRACT FROM AUTHOR]

The performance of all active photonic devices today is greatly limited by loss. Here, we show that one can engineer a low loss path in a metal-clad lossy multi-mode waveguide while simultaneously achieving high-performance active photonic devices. We leverage non-Hermitian systems operating beyond the exceptional point to enable the redistribution of losses in a multi-mode photonic waveguide. Consequently, our multi-mode waveguide offers low propagation losses for fundamental mode while other higher order modes experience prohibitively high losses. Furthermore, we show an application of this non-Hermitian waveguide platform in designing power-efficient thermo-optic phase shifters with significantly faster response times than conventional silicon-based thermo-optic phase shifters. Our device achieves a propagation loss of less than 0.02 dB μm−1 for our non-Hermitian waveguide-based phase shifters with high performance efficiency of Pπ ⋅ τ = 19.1 mW μs. In addition, our phase shifters have significantly faster response time (rise/fall time), τ ≈ 1.4 μs, compared to traditional silicon based thermo-optic phase shifters. [ABSTRACT FROM AUTHOR]

Bridges, as public structures, are national infrastructure structures. The investment requirements and demands for safe operation should put them at the forefront of engineers' attention. The important SNP bridge in Bratislava (Slovakia), which is one of the first bridges in the world to be suspended entirely on cables, has been the subject of a diagnosis of its health after 50 years of operation. The article describes and documents the individual steps of this diagnostics ‐ identification of the rope material, the status of the rope material and its current strength properties, and the experimentally and computationally determination of the forces in the individual ropes and their cables. The uniqueness of all the diagnostic steps was that they were carried out directly in the outdoor conditions of full operation of the bridge. The achieved results are briefly documented in the paper. Conclusions and further necessary steps for the final comprehensive safety assessment of the bridge operation are formulated. [ABSTRACT FROM AUTHOR]

The purpose of this study was to address issues of potential gender bias in pre-service elementary teachers' conceptions of engineers and engineering using Freire's (2018) Critical Consciousness perspective. By identifying the biasness as causal and structural attributions, the study also aimed to construct a critical pedagogy framework for future pre-service elementary teachers to reflect on and to radically reimagine and transform potential gender bias in their conceptions of engineers and engineering. Drawings of engineers and narratives of drawings from 115 pre-service elementary teachers served as data. The analysis comprised a two-step process: (1) identification of patterns through an inductive analysis of the data; and (2) analysis of patterns from the Critical Consciousness perspective to generate themes. Themes included: (1) depictions of male engineers being afforded privileges of having innate abilities to perform engineering from the standpoint of strong disciplinary backgrounds in mathematics and science while depictions of female engineers being afforded privileges of having innate abilities to perform engineering from the standpoint of computing, designing, and coding. (2) depictions of male engineers' "work" of engineering being related to tangible outcomes like physical products, and (3) depictions of male engineers as authority figures and having the ability to lead the work of engineering. The critical pedagogical framework constructed is a step toward developing a tool for critically reflecting, and radically imagining, reimagining, and thus transforming inequities inherent in future pre-service elementary teachers' conceptualizations of engineers and engineering. [ABSTRACT FROM AUTHOR]

For the last few decades, for the liquefaction susceptibility assessment of a location, Standard Penetration Test (SPT) based methods have been generally practiced. In this research, the liquefaction potential of Dhaka Metropolitan Development Plan (DMDP) area has been analyzed using three existing Cone Penetration Test (CPT) based methods. CPT (CPTu and SCPT) data have been collected from 546 locations of the DMDP region covering 1530 square kilometer area and have been analyzed to assess the liquefaction potential. Bangladesh is located in the junction of Indian and Eurasian plate, which makes this country vulnerable to earthquakes. A magnitude 7.5 earthquakes and Peak Ground Acceleration (PGA) value of 0.21 g at the surface have been used to evaluate the liquefaction susceptibility of the region using the three CPT-based techniques and another CPT-based technique has been employed to evaluate the liquefaction susceptibility of the region using variable surface PGA based on Modhupur scenario. Liquefaction potential maps have been proposed and compared for these four methods. It has been found that more than 60% of the study area falls within the LPI range which indicates moderate to relatively high liquefaction vulnerability. The liquefaction susceptibility of the three methods has been found to be in agreement and possible reasons of deviation in any particular method have been explained. Also, Ishihara 1985 proposed LPIISH has been estimated and compared with Iwasaki's LPI values. It has been observed that the difference in results using LPI and LPIISH are not significant. The seismic microzonation and liquefaction analyses will help engineers, planners and relevant professionals to get prior idea about the seismic vulnerability of any part of the DMDP region and take measures beforehand to avoid any damaging consequences. [ABSTRACT FROM AUTHOR]

Introduction: Chronic subdural hematoma (CSDH) often occurs 3 weeks to 3 months after brain injury, which is mainly caused by bleeding of the bridging vein. For patients with ventriculoperitoneal (V-P) shunt, excessive drainage can also cause CSDH. We present a rare case of CSDH caused by shunt valve breakdown in brain injury. Case Report: We report a 68-year-old man with V-P shunt for 8 years. He presented with bilateral CSDH with disappearance of lateral ventricles nearly 1 month after a brain injury caused by being hit with a stick. After burr hole drainage (BHD), the patient's symptoms improved and lateral ventricles reappeared, but disappeared rapidly with CSDH recurrence within a short time. We considered the cause to be medium pressure shunt valve breakdown caused by hitting with a stick, which was confirmed by the engineer's test after the operation and excessive drainage of cerebrospinal fluid. BHD replaced the adjustable pressure shunt valve, and the patient recovered. Conclusion: V-P shunt is a common operation in neurosurgery, and postoperative shunt valve breakdown may lead to poor outcome. We report a rare case of CSDH caused by shunt valve breakdown due to excessive external forces, suggesting that patients after V-P shunt should pay attention to the protection of the shunt valve. [ABSTRACT FROM AUTHOR]

This paper studies the role of trade for the joint uptake of AI‐enabled automation in manufacturing and engineering. It develops an agent‐based model (ABM) where the agents are heterogeneous manufacturers and engineering firms. The ABM features two technology‐related business models: engineering as a face‐to‐face consultancy service and engineering as automated software. The software adoption rate follows an S‐shaped curve for manufacturers and a boom and bust cycle for engineers. In the early phase, shortage of engineers constrains AI uptake, while engineers become abundant when AI is fully adopted. Trade affects the cut‐off productivity level at which manufacturers switch technology, the shape of the adoption rate curve, and the incentives for engineers to develop software. Bulky transactions and different productivity distributions across countries are drivers of trade in their own right. [ABSTRACT FROM AUTHOR]

The lower chamber of tower J17 from the Aurelian Walls in Rome is covered by a singular brick vault by slices that is almost completely preserved. This kind of vault is unusual in a Roman context and specifically in Aurelian Walls. Brick vaults by slices were extensively studied by the French engineer Auguste Choisy, who mainly scrutinized their ease of construction that doesn't require formwork and can adapt to different plans to achieve lowered vaults. The best-known examples are in Byzantium and generally in the Eastern Roman Empire, while we don't know many cases dating from late Roman antiquity on the Italian peninsula. Based on a rigorous photogrammetric survey and thorough data management, a detailed analysis of this vault allows us to establish a hypothesis about its construction process and to deepen the knowledge of this type of structure. [ABSTRACT FROM AUTHOR]

Despite major breeding efforts by various national and international agencies, yields for the ~40 million hectares of maize, the major food crop in sub‐Saharan Africa, have stagnated at <2 tons/ha/year for the past decade, one‐third the global average. Breeders have succeeded in breeding increased yield with a modicum of tolerance to some single‐weed or pathogen stresses. There has been minimal adoption of these varieties because introgressing polygenic yield and tolerance traits into locally adapted material is very challenging. Multiple traits to deal with pests (weeds, pathogens, and insects) are needed for farmer acceptance, because African fields typically encounter multiple pest constraints. Also, maize has no inherent resistance to some of these pest constraints, rendering them intractable to traditional breeding. The proposed solution is to simultaneously engineer multiple traits into one genetic locus. The dominantly inherited multi‐pest resistance trait single locus can be bred simply into locally adapted, elite high‐yielding material, and would be valuable for farmers, vastly increasing maize yields, and allowing for more than regional maize sufficiency. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In the context of rock material and modeling uncertainties, the optimization of rock tunnel support systems is often conducted by selecting the most cost‐effective solution among several feasible options that typically rely on the engineer's experience, potentially leading to overlooking the most optimal design. To improve such a limitation, this paper presents a multi‐objective reliability‐based robust design, considering the cost, safety, and design robustness systematically while maintaining the computational efficiency. In this framework, the uncertainty‐based reliability constrains is performed using the first‐order reliability method (FORM) and an improved Hasofer–Lind–Rackwits–Fiessler recursive algorithm (iHLRF‐x). The design robustness, in terms of sensitivity index (SI), is evaluated using the normalized gradient of the system response to the noise factors, which can be efficiently obtained from the output of FORM analysis. Then, the Pareto front revealing the tradeoff between multiple objectives can be directly generated using the proposed optimization framework. To illustrate the effectiveness of this procedure, a set of the optimal design combinations of the shotcrete thickness and installation position for the exampled rock tunnel are obtained, and new perspectives pertaining the success of the reliability‐based robust designs are provided. [ABSTRACT FROM AUTHOR]

This work aims to study the trajectory of the architect Frei Otto (FO) using an exploratory analysis of his projects, which pays special attention to the conceptual and chronological temporal evolution, the type of structures designed, and the relationship with his partners for his built and unbuilt projects. In the latter case, the projects developed, not requested, that are not part of his built works have been approached (i.e., not considered under competition). The main results indicate that FO's architectural trajectory, from a chronological point of view, was intense, which is generally reflected throughout the years. The 1950s–1970s were very productive. In addition to the large number of projects, there were innovative designs for quantity and structural innovation in Germany and other countries (e.g., France and Saudi Arabia). The analyses that were carried out made it possible to ascertain FO's professional and academic influence, which has been reflected in his projects. Likewise, his relationships with his collaborators have been long-lasting in some cases. Practical Applications: This work aimed to study the work of the architect and engineer Frei Otto (FO), of recognized prestige by the awards received and his colleagues. Some mention the scarce diffusion of his work. The interest of this work lies mainly in making known to professionals, academics, and the general public, in a short format, such as that used in scientific papers, the design of his structures, built and unbuilt. As Félix Candela mentions about FO's career, he is a typical and outstanding example of architectural innovation who concentrated his vocation and efforts on the study and research of tensile structures. His international projection and toward the citizen, give Frei Otto academic interest. This work is developed from different perspectives, which include chronological, type of structure, the location and function of the project, and the collaborators he worked with, with whom he shared his innovation and construction activities. Attention has been paid to a collection of unpublished or little-known projects by FO. [ABSTRACT FROM AUTHOR]

The paper presents a fatigue test of AA2519 T62 aluminium alloy in high-cycles region for smooth and notched specimens with stress concentration factors 1.75 and 2.28 for radii r1 = 2 mm and r2 = 1 mm, respectively. A number of cycles with no notch effect was determined for each notched specimens. The estimated values were compared with the distribution estimated on the literature data. Based on this knowledge, an analytical-experimental method was proposed to determine S-N curves for notched elements for aluminium alloys. The verification of the method gives satisfactory results. Additionally, the FITNET method and the Lee and Taylor method were used for comparison. The proposed method got the best results. The FITNET method and Lee and Taylor method obtained overestimated fatigue life and it can be concluded that the analytical method presented methods are suitable for steel materials. The proposed method can be used by engineers. [ABSTRACT FROM AUTHOR]

Novel chimeric antigen receptor (CAR) T-cell approaches are needed to improve therapeutic efficacy in solid tumors. High-risk neuroblastoma is an aggressive pediatric solid tumor that expresses cell-surface GPC2 and GD2 with a tumor microenvironment infiltrated by CD16a-expressing innate immune cells. Here we engineer T-cells to express a GPC2-directed CAR and simultaneously secrete a bispecific innate immune cell engager (BiCE) targeting both GD2 and CD16a. In vitro, GPC2.CAR-GD2.BiCE T-cells induce GPC2-dependent cytotoxicity and secrete GD2.BiCE that promotes GD2-dependent activation of antitumor innate immunity. In vivo, GPC2.CAR-GD2.BiCE T-cells locally deliver GD2.BiCE and increase intratumor retention of NK-cells. In mice bearing neuroblastoma patient-derived xenografts and reconstituted with human CD16a-expressing immune cells, GD2.BiCEs enhance GPC2.CAR antitumor efficacy. A CAR.BiCE strategy should be considered for tumor histologies where antigen escape limits CAR efficacy, especially for solid tumors like neuroblastoma that are infiltrated by innate immune cells. GPC2 and GD2 have been described as immunotherapeutic targets in neuroblastoma. Here the authors engineer T cells to simultaneously express a GPC2-directed CAR and a bispecific innate immune cell engager targeting GD2 and CD16a, showing antitumor activity in neuroblastoma preclinical models. [ABSTRACT FROM AUTHOR]

Numerous reviews are available in the literature on PV inverter topologies. These reviews have intensively investigated the available PV inverter topologies from their modulation techniques, control strategies, cost, and performance aspects. However, their compliance with industrial standards has not been investigated in detail so far in the literature. There are various standards such as North American standards (UL1741, IEEE1547, and CSA 22.2) and Australian and European safety standards and grid codes, which include IEC 62109 and VDE. These standards provide detailed guidelines and expectations to be fulfilled by a PV inverter topology. Adherence to these standards is essential and crucial for the successful operation of PV inverters, be it a standalone or grid-tied mode of operation. This paper investigates different PV inverter topologies from the aspect of their adherence to different standards. Both standalone and grid-tied mode of operation-linked conditions have been checked for different topologies. This investigation will help power engineers in selecting suitable PV inverter topology for their specific applications. [ABSTRACT FROM AUTHOR]

Artificial neuromorphic devices can emulate dendric integration, axonal parallel transmission, along with superior energy efficiency in facilitating efficient information processing, offering enormous potential for wearable electronics. However, integrating such circuits into textiles to achieve biomimetic information perception, processing, and control motion feedback remains a formidable challenge. Here, we engineer a quasi-solid-state iontronic synapse fiber (ISF) comprising photoresponsive TiO2, ion storage Co-MoS2, and an ion transport layer. The resulting ISF achieves inherent short-term synaptic plasticity, femtojoule-range energy consumption, and the ability to transduce chemical/optical signals. Multiple ISFs are interwoven into a synthetic neural fabric, allowing the simultaneous propagation of distinct optical signals for transmitting parallel information. Importantly, IFSs with multiple input electrodes exhibit spatiotemporal information integration. As a proof of concept, a textile-based multiplexing neuromorphic sensorimotor system is constructed to connect synaptic fibers with artificial fiber muscles, enabling preneuronal sensing information integration, parallel transmission, and postneuronal information output to control the coordinated motor of fiber muscles. The proposed fiber system holds enormous promise in wearable electronics, soft robotics, and biomedical engineering. [ABSTRACT FROM AUTHOR]

Live vaccines are ideal for inducing immunity but suffer from the need to attenuate their pathogenicity or replication to preclude the possibility of escape. Unnatural amino acids (UAAs) provide a strategy to engineer stringent auxotrophies, yielding conditionally replication incompetent live bacteria with excellent safety profiles. Here, we engineer Pseudomonas aeruginosa to maintain auxotrophy for the UAA p-benzoyl-l-phenylalanine (BzF) through its incorporation into the essential protein DnaN. In vivo evolution using an Escherichia coli-based two-hybrid selection system enabled engineering of a mutant DnaN homodimeric interface completely dependent on a BzF-specific interaction. This engineered strain, Pa Vaccine, exhibits undetectable escape frequency (<10−11) and shows excellent safety in naïve mice. Animals vaccinated via intranasal or intraperitoneal routes are protected from lethal challenge with pathogenic P. aeruginosa PA14. These results establish UAA-auxotrophic bacteria as promising candidates for bacterial vaccine therapy and outline a platform for expanding this technology to diverse bacterial pathogens. In this work, authors develop a live vaccine candidate against Pseudomonas aeruginosa using an unnatural amino acid-based auxotrophic strategy. They provide insight on the vaccine's in vivo safety profile and protection of mice against lethal P. aeruginosa challenge. [ABSTRACT FROM AUTHOR]

This document discusses the increasing demand for high-efficient isolated DC/DC converters in renewable energy applications. It presents seventeen papers that cover various topics such as reducing switch count and current balancing, addressing voltage ringing issues, solving current unbalance problems, and optimizing converter design. The papers provide experimental results and propose innovative methods to improve the efficiency and performance of DC/DC converters in renewable energy applications. The document also includes three research papers related to power converters, including one on a prototype for NanoGrid applications, one on a new DC-DC bipolar resonance converter, and one on enhancing the stability of a DCMG cluster. The text also includes acknowledgments and biographies of the guest editors. [Extracted from the article]

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Structured marine clay is commonly encountered in offshore engineering projects and engineers are concerned about its impact on the engineering properties of marine clay as well as its correlation with index properties. Current research has emphasized the role of soil structure in these aspects of marine clay. In this study, we investigated the influence of depositional environment and oxidation-induced evolution of clay microstructure on the formation of clay structure in structured clay from Zhanjiang area, a coastal city located in South China. The distinct soil structure observed in marine-terrigenous clay deposited under different environments exhibited sensitivity ranging from 1.6 to 8.9 at varying moisture content levels. The wide range of sensitivity observed in structured marine-terrigenous clay was attributed to free iron oxide derived from siderite present in an acidic environment. Compared to other regions, Zhanjiang marine clay demonstrated favorable mechanical properties but poor physical properties due to its unique clay structure characteristics. Based on these findings, we proposed a modified approach for correlating index properties with engineering properties that yielded good predictions. [ABSTRACT FROM AUTHOR]

4E approaches to affective technology tend to focus on how 'users' manage their situated affectivity, analogously to how they help themselves cognitively through epistemic actions or using artefacts and scaffolding. Here I focus on cases where the function of affective technology is to exploit or manipulate the agent engaging with it. My opening example is the cigarette, where technological refinements have harmfully transformed the affective process of consuming nicotine. I proceed to develop case studies of two very different but also harmful affective technologies. Casinos and electronic gambling machines deploy computationally intensive scaffolding to shape the onset and continuation of gambling episodes. High-heeled shoes affectively engineer wearers' relationships to their own embodied capacities and are predominantly expected to be worn by women. I conclude with a discussion of the need for study of affective technology to focus other-directed applications, some of which will serve competing or antagonistic interests. [ABSTRACT FROM AUTHOR]

The employment of Business Information Modeling (BIM) may assist the resident engineering department in reaching its long-term strategic goals. The suggested computer software was created and tested using the first package of new projects for roads, bridges, and tunnels aimed at solving the traffic congestion crisis taking place in the capital city of Iraq, Baghdad. In the context of the current study, questionnaires and personal interviews with specialists in the field of road, tunnel, and overpass construction were employed. The aim of implementing BIM is to assess the introduced program's efficiency, verify its performance, and identify any errors, defects, or challenges that users may encounter during its application. The computer program underwent successful testing at several Resident Engineer's Offices (REOs) within the initial package of new projects aimed at addressing traffic congestion issues in Baghdad through independent verification checks. Initially, the program was utilized with the assistance of a user guide to facilitate its operation and provide a detailed description of each program feature which can provide effective decisionmaking and enhance REOs' computer skills. [ABSTRACT FROM AUTHOR]

This article explores the concept of engineers' boundary work, focusing on their professional knowledge and interaction strategies as they navigate complex challenges. It discusses how engineers establish and defend their professional boundaries, as well as the role of gender and race in shaping these boundaries. The article also examines how engineers adapt and expand their roles, including taking on management and business responsibilities. It highlights the resistance to interdisciplinary education in engineering schools and the strategic manipulation of boundaries within collaborative projects. Additionally, the article explores the relationship between engineering and environmental activism, and the evolving attitudes towards integrating activism into professional identity. Overall, the article emphasizes that engineers' boundary work is influenced by social hierarchies and cultural norms, and is continuously renegotiated in response to changing responsibilities and societal expectations. [Extracted from the article]

This paper explores three different forms of negotiation implemented by environmentalist engineers between their professional work and their environmental activism. These engineers, members of environmentalist organizations, appropriate in different ways this conceptual professional boundary that separates and opposes the social worlds of engineering and activism. The article draws from narrative interviews with 50 environmentalist engineers that focused on the dynamics of these negotiations and their effects on biographical trajectories. The process of conforming, shifting or overstepping the boundary between profession and activism is linked to the framing of environmental causes. The precarious balances these engineers strike between work and activism thus depend on three factors: the emergence (or not) of a professional reflexivity, the adoption (or not) of a political interpretation and the reaction of hierarchical superiors and company management. [ABSTRACT FROM AUTHOR]

Robotic chefs are a promising technology that can improve the availability of quality food by reducing the time required for cooking, therefore decreasing food's overall cost. This paper clarifies and structures design and benchmarking rules in this new area of research, and provides a comprehensive review of technologies suitable for the construction of cooking robots. The diner is an ultimate judge of the cooking outcome, therefore we put focus on explaining human food preferences and perception of taste and ways to use them for control. Mechanical design of robotic chefs at a practically low cost remains the challenge, but some recently published gripper designs as well as whole robotic systems show the use of cheap materials or off‐the‐shelf components. Moreover, technologies like taste sensing, machine learning, and computer vision are making their way into robotic cooking enabling smart sensing and therefore improving controllability and autonomy. Furthermore, objective assessment of taste and food palatability is a challenge even for trained humans, therefore the paper provides a list of procedures for benchmarking the robot's tasting and cooking abilities. The paper is written from the point of view of a researcher or engineer building a practical robotic system, therefore there is a strong priority for solutions and technologies that are proven, robust and self‐contained enough to be a part of a larger system. [ABSTRACT FROM AUTHOR]

Ontologies constitute the semantic model of Knowledge Graphs (KGs). This structural association indicates the potential existence of methodological analogies in the development of ontologies and KGs. The deployment of fully and well-defined methodologies for KG development based on existing ontology engineering methodologies (OEMs) has been suggested and efficiently applied. However, most of the modern/recent OEMs may not include tasks that (i) empower knowledge workers and domain experts to closely collaborate with ontology engineers and KG specialists for the development and maintenance of KGs, (ii) satisfy special requirements of KG development, such as (a) ensuring modularity and agility of KGs, (b) assessing and mitigating bias at schema and data levels. Toward this aim, the paper presents a methodology for the Collaborative and Hybrid Engineering of Knowledge Graphs (CHEKG), which constitutes a hybrid (schema-centric/top-down and data-driven/bottom-up), collaborative, agile, and iterative approach for developing modular and fair domain-specific KGs. CHEKG contributes to all phases of the KG engineering lifecycle: from the specification of a KG to its exploitation, evaluation, and refinement. The CHEKG methodology is based on the main phases of the extended Human-Centered Collaborative Ontology Engineering Methodology (ext-HCOME), while it adjusts and expands the individual processes and tasks of each phase according to the specialized requirements of KG development. Apart from the presentation of the methodology per se, the paper presents recent work regarding the deployment and evaluation of the CHEKG methodology for the engineering of semantic trajectories as KGs generated from unmanned aerial vehicles (UAVs) data during real cultural heritage documentation scenarios. [ABSTRACT FROM AUTHOR]

This article explores a more streamlined approach to Failure Mode and Effects Analysis (FMEA) to enhance efficiency for smaller issues. FMEA is a method used to identify and prioritize potential failures in a system, process, or design. The traditional FMEA practice has limitations, such as a one-size-fits-all format that can lead to inefficiency and a lack of assessment of return on investment. One challenge in conducting FMEA is the lack of data to support meaningful risk scoring. The article suggests that in situations where in-depth assessment is not feasible, alternative approaches or customizations can be considered to reduce the burden and cost. The article emphasizes the importance of considering return on investment when making business decisions, even if the risk priority number is low. It proposes using simpler risk analysis practices when data is limited or resources are constrained, such as a three-level scale instead of the traditional 10-level scale for risk assessment. The article acknowledges potential resistance to this approach but argues that it can be more efficient and effective. The concept of tiered triage, where initial risk assessment is conducted using a simpler technique and then transitioning to traditional practices for post-action assessment, is also discussed. [Extracted from the article]

Summary: Leaf decomposition varies widely across temperate forests, shaped by factors like litter quality, climate, soil properties, and decomposers, but forest heterogeneity may mask local tree influences on decomposition and litter‐associated microbiomes. We used a 24‐yr‐old common garden forest to quantify local soil conditioning impacts on decomposition and litter microbiology.We introduced leaf litter bags from 10 tree species (5 arbuscular mycorrhizal; 5 ectomycorrhizal) to soil plots conditioned by all 10 species in a full‐factorial design. After 6 months, we assessed litter mass loss, C/N content, and bacterial and fungal composition. We hypothesized that (1) decomposition and litter‐associated microbiome composition would be primarily shaped by the mycorrhizal type of litter‐producing trees, but (2) modified significantly by underlying soil, based on mycorrhizal type of the conditioning trees.Decomposition and, to a lesser extent, litter‐associated microbiome composition, were primarily influenced by the mycorrhizal type of litter‐producing trees. Interestingly, however, underlying soils had a significant secondary influence, driven mainly by tree species, not mycorrhizal type. This secondary influence was strongest under trees from the Pinaceae.Temperate trees can locally influence underlying soil to alter decomposition and litter‐associated microbiology. Understanding the strength of this effect will help predict biogeochemical responses to forest compositional change. [ABSTRACT FROM AUTHOR]

The sluggish kinetics of Volmer step in the alkaline hydrogen evolution results in large energy consumption. The challenge that has yet well resolved is to control the water adsorption and dissociation. Here, we develop biaxially strained MoSe2 three dimensional nanoshells that exhibit enhanced catalytic performance with a low overpotential of 58.2 mV at 10 mA cm−2 in base, and long-term stable activity in membrane-electrode-assembly based electrolyser at 1 A cm−2. Compared to the flat and uniaxial-strained MoSe2, we establish that the stably adsorbed OH engineer on biaxially strained MoSe2 changes the water adsorption configuration from O-down on Mo to O-horizontal on OH* via stronger hydrogen bonds. The favorable water dissociation on 3-coordinated Mo sites and hydrogen adsorption on 4-coordinated Mo sites constitute a tandem electrolysis, resulting in thermodynamically favorable hydrogen evolution. This work deepens our understanding to the impact of strain dimensions on water dissociation and inspires the design of nanostructured catalysts for accelerating the rate-determining step in multi-electron reactions. Hydroxide is the most abundant anion in alkaline solutions, but its impact on alkaline water electrolysis remains unclear. Herein, the authors report a biaxial strain induced OH engineer on MoSe2 to accelerate alkaline hydrogen evolution by modifying the water dissociation. [ABSTRACT FROM AUTHOR]

The identification of spray-drying processing parameters capable of producing particles suitable for pulmonary inhalation with retained bioactivity underpins the development of inhalable biotherapeutics. Effective delivery of biopharmaceuticals via pulmonary delivery routes such as dry powder inhalation (DPI) requires developing techniques that engineer particles to well-defined target profiles while simultaneously minimising protein denaturation. This study examines the simultaneous effects of atomisation gas flow rate on particle properties and retained bioactivity for the model biopharmaceutical lysozyme. The results show that optimising the interplay between atomisation gas flow rate and excipient concentration enables the production of free-flowing powder with retained bioactivity approaching 100%, moisture content below 4%, and D50 < 4 µm, at yields exceeding 50%. The developed methodologies inform the future design of protein-specific spray-drying parameters for inhalable biotherapeutics. [ABSTRACT FROM AUTHOR]

An innovative approach that combines isogeometric analysis (IGA), limit analysis, machine learning, and the multivariate adaptive regression splines (MARS) model is presented in this paper to investigate sinkhole stability of circular cavity. The upper bound limit analysis method using IGA and second-order cone programming (SOCP) is employed to analyze circular cavity stability. Based on Bézier extraction, the non-uniform rational B-spline (NURBS) is used to generate a set of NURBS surfaces that define the boundary of the soil domain. The proposed approach is validated through comparative analysis with previous studies, demonstrating its effectiveness in accurately predicting soil stability. A large dataset consisting of 5000 randomly generated runs is used to train the machine learning algorithm that is integrated with the MARS model. The results show high accuracy, with a small mean squared error of 10–3, in predicting the undrained stability of circular cavities. The integration of IGA, limit analysis, machine learning, and the MARS model contributes significantly to advancing computational techniques for assessing soil stability. The proposed approach offers a comprehensive and precise tool for engineers and researchers, providing an accurate design formula for evaluating the undrained stability of circular cavities. [ABSTRACT FROM AUTHOR]

Segmental tunnel linings have a complex structural behavior that is difficult to predict. Full-scale in situ structural monitoring allows us to gain access to these structures, observe the acting mechanisms, and better understand the actual structural behavior under realistic boundary conditions. In a recent structural monitoring project in Frankfurt, Germany, strains, deformations, and temperatures were measured at the segmental lining of a twin-tube tunnel boring machine (TBM) tunnel. Hereby, internal forces were back-calculated from the strain measurements. The results of the monitoring are presented and discussed in this paper. The measurements began immediately after the assembly of the segments and have been performed continuously over several years. Because of that, it was possible to observe that the internal forces differ significantly between the construction stage and the final state. During the construction stage, the internal forces develop quickly within hours after ring assembly, showing a distribution along the lining's circumference that is hard to predict. Almost all radial deformations occur during this period and remain unchanged afterward. After this first early phase, a period of stress redistribution follows, including significant changes in the internal forces. At its end, the stable, final state is reached. In this state, the internal forces match better with expectations. In the monitored areas, the stresses during the construction stage slightly exceeded those of the final state, which should be avoided for economic reasons. Additional investigations regard the temperature development within the lining, the influence of the second tube construction on the already built tube, and the development of longitudinal ring interaction over time. The latter significantly influences the structural behavior, but its development is often subject to uncertainties. In this case, it was observed that the longitudinal interaction decreases considerably over time. Practical Applications: In the structural design of segmental tunnel linings, structural or geotechnical engineers have various options regarding the available calculation methods and modeling strategies. All of these options are part of the state of the art, and the selection is up to the engineer. However, the results can be quite different depending on the chosen option. Consequently, uncertainties remain regarding the real linings' internal forces and structural reliability. The actual mechanisms can be identified by investigating the real structural behavior of segmental tunnel linings with in situ structural monitoring. Then, with back-analyses, on the one hand, it can be tested to determine how well different calculation methods and modeling strategies correspond to reality. On the other hand, the monitoring data can contribute to improving existing calculation methods, developing new modeling approaches, and establishing more detailed recommendations or optimizations regarding the design and construction of segmental tunnel linings. This paper presents findings derived from a structural monitoring project on a segmental lining. Different mechanisms and aspects, sometimes uncertain or debatable in tunnel design, are discussed regarding their real in situ appearance. The gained data will also be used for further back-analyses and investigations. [ABSTRACT FROM AUTHOR]

This text provides a summary of the contributions of Angus Mackay and the Dow brothers to agricultural journalism and education in nineteenth-century Australia. Angus Mackay, a farmer, journalist, engineer, and politician, was involved in various community organizations and wrote books on topics such as cotton, sugar cane, and agriculture in Queensland. He also represented Queensland at the United States Centennial Exposition in Philadelphia in 1876, where he gathered information on agricultural innovations. The Dow brothers, self-taught in agriculture, were vocal supporters of agricultural education and wrote books about their experiences. Both Mackay and the Dow brothers provided valuable information and advice to small holders and yeoman farmers. The document references various sources related to farming in Australia, including books and articles by TK Dow, Eric Richards, and SM Wadham. [Extracted from the article]

Lawrence Livermore National Laboratory researchers have developed a light-responsive material called a liquid crystal elastomer (LCE) that can change shape when exposed to light. This discovery could have applications in fields such as robotics and medicine, allowing for the creation of soft machines that can mimic the movements of living organisms. However, there are still challenges to overcome before the material can be used practically, such as designing specific modes of motion and improving durability and efficiency. The research was published in the journal Matter. [Extracted from the article]

Many powerful metamodeling platforms enabling model-driven software engineering (MDSE) exist, each with its strengths, weaknesses, functionalities, programming language(s), and developer community. Platform interoperability would enable users to exploit their mutual benefits. Such interoperability would allow the transformation of metamodels and models created in one platform into equivalent metamodels and models in other platforms. Language engineers could then freely choose the metamodeling platform without risking a lock-in effect. Two well-documented and publicly available metamodeling platforms are the eclipse modeling framework (EMF) and the modeling SDK for visual studio (MSDKVS). In this paper, we propose an M3-level-bridge (M3B) that establishes interoperability between EMF and MSDKVS on the abstract syntax level and on the graphical concrete syntax level. To establish such interoperability we (i) compare the two platforms, (ii) present a conceptual mapping between them, and (iii) implement a bidirectional transformation bridge including both the metamodel and model layer. We evaluate our approach by transforming a collection of publicly available metamodels and automatically generated or manually created models thereof. The transformation outcomes are then used to quantitatively and qualitatively evaluate the transformation's validity, executability, and expressiveness. [ABSTRACT FROM AUTHOR]

This paper introduces a current control method for permanent magnet synchronous motors (PMSMs) using a disturbance sliding mode observer (DSMO) in conjunction with a linear quadratic regulator (LQR). This approach enhances control performance, streamlines the tuning of controller parameters, and offers robust optimal control that is resistant to system disturbances. The LQR controller based on state feedback is advantageous for its simplicity in parameter adjustment and achieving an optimal control effect easily under specific performance indicators. It is suitable for the optimal control of strong linear systems that can be accurately modeled. However, most practical systems are difficult to model accurately, and the time-varying system parameters and existing nonlinearity limit the engineering application of LQR. In the PMSM current control loop, there is strong nonlinear disturbance manifesting as the nonlinearity of its dynamic model. Additionally, substantial noise and variations in system parameters within actual motor circuits hinder the linear quadratic regulator from attaining optimal performance. A disturbance sliding mode observer is proposed to enhance the LQR controller, enabling superior performance in nonlinear current loop control. Simulation and actual hardware experiments were conducted to verify the performance and robustness of the control scheme proposed in this paper. Compared with the widely used PI controller in engineering and sliding mode control (SMC) specialising in disturbance rejection, it offers the advantage of straightforward parameter tuning and can swiftly achieve the robust and optimal control performance that engineers prioritize. [ABSTRACT FROM AUTHOR]

The main objective of this article is to determine the relationship between mobile money services and the growth of small and medium enterprises (SMEs). A sample of 50 SMEs was collected. The probit model was used to estimate the result. The study established that mobile money services have a positive and significant relationship with the growth of SMEs. The determinants of mobile money services observed are; experience in business management, frequency of bill payment, size of business, male entrepreneur, operation of mobile money account, frequency of purchasing airtime, distance to financial institutions, number of business branches, mobile money accounts held, secondary education, technical support, location of business, number of workers and size of capital transaction. The challenges faced by entrepreneurs in mobile money transactions observed are: wrong manipulation of account, delays, environmental complexities, and loss of money due to hawkers. The result suggests that SMEs should intensify the use of mobile money services in their daily business transactions. It is a wise step toward business expansion. Entrepreneurs of SMEs should take advantage of the drivers of mobile money services to encourage the diverse use of digital technologists. Finally, entrepreneurs should avoid risky manipulations of their mobile money gargets. [ABSTRACT FROM AUTHOR]

Engineering design and construction teams commonly use decision tools, such as rating systems, to manage the complexity of infrastructure projects. However, these systems often focus predominantly on environmental dimensions, potentially overlooking the holistic economic and social aspects of sustainability. This can hinder decision-makers from recognizing the benefits, thereby inadvertently impeding optimal sustainability performance. This research explores a potential solution: reframing the goals of credits on rating systems to explicitly highlight the interconnectedness of environmental, social, and financial dimensions. The aim was to amplify engineers' motivation towards higher levels of sustainability performance. The study examined the effect of the goal-framed credits by comparing the sustainability scores between engineering professionals (n=42) who used the original Envision system and the reframed version when evaluating a case project. The control group participants averaged a score of 95.4 Envision points (37%), while the intervention group averaged 121.8 Envision points (48%). The reframed credits significantly increased engineering professionals' sustainability goal setting. Emphasizing financial and social objectives on credits from the Envision rating system, rather than solely focusing on the existing environmental goals, had a favorable influence on professionals' sustainable design choices. This reframing, by emphasizing the interconnectedness of environmental, social, and financial dimensions of each decision, appears to amplify the awareness, motivation, and selection of higher levels of sustainability achievement, thereby increasing their perceived value and leading to a shift in sustainability-oriented decision-making. The findings suggest that reframing rating systems to better emphasize the interconnectedness of the environmental, social, and financial dimensions of each decision can serve to help engineering teams set higher goals for sustainable performance. Practical Applications: For infrastructure project managers, architects, and designers, this research highlights the significance of considering economic and social aspects alongside environmental concerns. By doing so, it can further empower stakeholders to make more well-rounded and sustainable decisions that benefit both their projects and the communities they serve. Small changes in how decision tools are worded, or framed, can have a significant effect on project goal setting. A better understanding of how framing affects design cognition can also help inform how project managers, architects, and designers present information to their clients. Subtle changes in the decision tools and the way information about projects is expressed cost little compared to the actual cost of infrastructure, offering inexpensive and easy to implement strategies to influence and nudge project teams toward setting higher sustainability goals during the design and construction of infrastructure projects. [ABSTRACT FROM AUTHOR]

The effective design of combinatorial libraries to balance fitness and diversity facilitates the engineering of useful enzyme functions, particularly those that are poorly characterized or unknown in biology. We introduce MODIFY, a machine learning (ML) algorithm that learns from natural protein sequences to infer evolutionarily plausible mutations and predict enzyme fitness. MODIFY co-optimizes predicted fitness and sequence diversity of starting libraries, prioritizing high-fitness variants while ensuring broad sequence coverage. In silico evaluation shows that MODIFY outperforms state-of-the-art unsupervised methods in zero-shot fitness prediction and enables ML-guided directed evolution with enhanced efficiency. Using MODIFY, we engineer generalist biocatalysts derived from a thermostable cytochrome c to achieve enantioselective C-B and C-Si bond formation via a new-to-nature carbene transfer mechanism, leading to biocatalysts six mutations away from previously developed enzymes while exhibiting superior or comparable activities. These results demonstrate MODIFY's potential in solving challenging enzyme engineering problems beyond the reach of classic directed evolution. The effective design of cold-start enzyme libraries to balance fitness and diversity enables access to enzyme variants that are readily evolvable and close to the optima in the fitness landscape. Here, the authors develop MODIFY (machine learning-optimized library design with improved fitness and diversity), a machine learning algorithm to co-optimize expected fitness and sequence diversity of starting libraries, enhancing the efficiency of directed evolution in enzyme engineering. [ABSTRACT FROM AUTHOR]

Recent discoveries in biology have highlighted the importance of protein and RNA-based condensates as an alternative to classical membrane-bound organelles. Here, we demonstrate the design of pure RNA condensates from nanostructured, star-shaped RNA motifs. We generate condensates using two different RNA nanostar architectures: multi-stranded nanostars whose binding interactions are programmed via linear overhangs, and single-stranded nanostars whose interactions are programmed via kissing loops. Through systematic sequence design, we demonstrate that both architectures can produce orthogonal (distinct and immiscible) condensates, which can be individually tracked via fluorogenic aptamers. We also show that aptamers make it possible to recruit peptides and proteins to the condensates with high specificity. Successful co-transcriptional formation of condensates from single-stranded nanostars suggests that they may be genetically encoded and produced in living cells. We provide a library of orthogonal RNA condensates that can be modularly customized and offer a route toward creating systems of functional artificial organelles for the task of compartmentalizing molecules and biochemical reactions. Protein and RNA-based condensates have emerged as biologically important alternatives to classical membrane-bound organelles. Here the authors design pure RNA condensates from nanostructured, star-shaped RNA motifs, and engineer them to recruit specific peptides and proteins. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) bioprinting belongs to the wide family of additive manufacturing techniques and employs cell-laden biomaterials. In particular, these materials, named "bioink", are based on cytocompatible hydrogel compositions. To be printable, a bioink must have certain characteristics before, during, and after the printing process. These characteristics include achievable structural resolution, shape fidelity, and cell survival. In previous centuries, scientists have created mathematical models to understand how physical systems function. Only recently, with the quick progress of computational capabilities, high-fidelity and high-efficiency "computational simulation" tools have been developed based on such models and used as a proxy for real-world learning. Computational science, or "in silico" experimentation, is the term for this novel strategy that supplements pure theory and experiment. Moreover, a certain level of complexity characterizes the architecture of contemporary powerful computational resources, known as high-performance computing (HPC) resources, also due to the great heterogeneity of its structure. Lately, scientists and engineers have begun to develop and use computational models more extensively to also better understand the bioprinting process, rather than solely relying on experimental research, due to the large number of possible combinations of geometrical parameters and material properties, as well as the abundance of available bioprinting methods. This requires a new effort in designing and implementing computational tools capable of efficiently and effectively exploiting the potential of new HPC computing systems available in the Exascale Era. The final goal of this work is to offer an overview of the models, methods, and techniques that can be used for "in silico" experimentation of the physicochemical processes underlying the process of 3D bioprinting of cell-laden materials thanks to the use of up-to-date HPC resources. [ABSTRACT FROM AUTHOR]

The dynamic response of a railway bridge depends on several parameters; the primary parameter is the fundamental natural frequency of vibration of the bridge itself. It is considered a critical parameter of the bridge as the driving or the forcing frequencies arising from moving trains may coincide with the fundamental frequency of the bridge and initiate a resonant response amplifying the bridge load effects. This condition may adversely affect the stresses experienced on bridge members and, consequently, the remaining fatigue life of the structure. Because the train adds additional time-varying mass to the bridge, this introduces a time-varying change in the bridge's fundamental natural frequency of vibration. As a result, train critical speeds will have a certain range depending on the train configuration. This article presents a simplified method using a power-law relationship to predict the frequency characteristics of a bridge as a function of the train-to-bridge mass ratio. The method is presented in a generalized form, which enables the frequency characteristics to be determined for any given combination of trains and simply supported bridges of short to medium span typically found on the UK rail network. The method is then demonstrated in a case study of a single-span, simply supported plate girder bridge. By considering the BS-5400 train traffic types, the proposed method is used to calculate bridge frequency effects, dynamic amplification, and train critical speed bandwidth for each train type. The simplicity of the proposed method, as it does not require any complex computational modeling, makes it an ideal and effective tool for the practicing engineer to carry out a quick and economical assessment of a bridge for any given train configuration. [ABSTRACT FROM AUTHOR]

Advancements in CRISPR technology, particularly the development of base editors, revolutionize genetic variant research. When combined with model organisms like zebrafish, base editors significantly accelerate and refine in vivo analysis of genetic variations. However, base editors are restricted by protospacer adjacent motif (PAM) sequences and specific editing windows, hindering their applicability to a broad spectrum of genetic variants. Additionally, base editors can introduce unintended mutations and often exhibit reduced efficiency in living organisms compared to cultured cell lines. Here, we engineer a suite of adenine base editors (ABEs) called ABE-Ultramax (Umax), demonstrating high editing efficiency and low rates of insertions and deletions (indels) in zebrafish. The ABE-Umax suite of editors includes ABEs with shifted, narrowed, or broadened editing windows, reduced bystander mutation frequency, and highly flexible PAM sequence requirements. These advancements have the potential to address previous challenges in disease modeling and advance gene therapy applications. CRISPR base editors are limited by protospacer adjacent motif (PAM) sequences and specific editing windows. Here, authors developed ABE-Ultramax, a suite of adenine base editors with high efficiency, low indel rates, and flexible PAM requirements, enabling precise biallelic editing in zebrafish. [ABSTRACT FROM AUTHOR]