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Asymmetric α-benzylation of cyclic ketones enabled by concurrent chemical aldol condensation and biocatalytic reduction
No full textChemoenzymatic cascade catalysis has emerged as a revolutionary tool for streamlining traditional retrosynthetic disconnections, creating new possibilities for the asymmetric synthesis of valuable chiral compounds. Here we construct a one-pot concurrent chemoenzymatic cascade by integrating organobismuth-catalyzed aldol condensation with ene-reductase (ER)-catalyzed enantioselective reduction, enabling the formal asymmetric α-benzylation of cyclic ketones. To achieve this, we develop a pair of enantiocomplementary ERs capable of reducing α-arylidene cyclic ketones, lactams, and lactones. Our engineered mutants exhibit significantly higher activity, up to 37-fold, and broader substrate specificity compared to the parent enzyme. The key to success is due to the well-tuned hydride attack distance/angle and, more importantly, to the synergistic proton-delivery triade of Tyr28-Tyr69-Tyr169. Molecular docking and density functional theory (DFT) studies provide important insights into the bioreduction mechanisms. Furthermore, we demonstrate the synthetic utility of the best mutants in the asymmetric synthesis of several key chiral synthons.BT/Biocatalysi
Analysing the Role of the Propulsive System in the Global Civil Aviation Energy Optimisation Framework
No full textThis paper presents a simple explanatory framework to analyse the diverse strategies proposed by the civil aviation sector in attempts to reconcile its growth tendencies with its impact on natural environment. Despite framing the industry as a single entity that has a problem to solve, it is better represented as a diverse set of actors, each responsible for various constituent systems at different phases of their respective life cycles. To elucidate this multi-actor pursuit of higher-level emergent objectives, the paper firstly presents an overview of different development scenarios dedicated to guide the industry towards sustainability. Given that the constituent systems tackled in such strategies strongly depend on each other, the sustainability objective relies on reconciling all the different agendas and contributions in unison, making them collectively compatible with the dynamics of the socio-economic and the natural world. To analyse the problem coherently, a basic description of an arbitrary system as a coarse-grained closed causal network is formulated. A categorisation for the model parameters is proposed to help define the system boundary and interaction with the environment unambiguously, dispensing with the need to know details of the model that represents the system at hand. This formalism was previously derived for preliminary sizing and performance estimation of aeroplane engines; by virtue of recursive nature of the coarse-graining process, the same formalism can be used to describe systems at any arbitrary levels, which enables a small system (in the current paper the system of interest being the propulsive system) to be integrated into a multi-level causal dependence framework. Then, the typical industry evolution scenarios are re-framed on the common ground of the causal network formalism. Subsequently, the framework is extended with a simple quantitative energy-based representation to formulate a qualitative case of how the scenarios could be formulated more coherently to avoid conflicting local optimisation objectives in pursuit of common higher-level goals. Finally, the entirety of the presented elements are brought together in a proposal to conceptualise an industrial system as a life cycle which exchanges matter, energy and information with its large-scale environment. The paper argues that such framing of the problem can pave the way to simplification of the problem of conflicting high-level objectives, by enabling a coherent understanding of the mutual dependence between a system of interest and the much more complex system of systems that is the aeronautical industry.System Engineerin
Scour Effect on the Lateral Bearing Behaviour of Monopiles Considering Different Slenderness Ratios
No full textScour leads to the loss of soil around monopile foundations for offshore wind turbines, which affects their structural safety. In this paper, the effect of scour on the lateral behaviour of monopiles was extensively investigated using finite element analysis, and calibration and comparison were undertaken using centrifuge tests. Piles with three slenderness ratios, i.e., 3, 5 and 8, were studied by keeping the diameter constant and varying the embedment length. Three scour types (local narrow, local wide and global) and four scour depths (0.5D, 1D, 1.5D and 2D; D signifies the pile diameter) were considered in this investigation. The results indicate that the lateral resistance of the pile is the greatest in the case of local narrow scour, followed by that in the cases of local wide scour and global scour. When the scour depth is larger than 1D, the influence of the scour type on the pile lateral bearing behaviour is insignificant. The influence of the scour type and scour depth on the pile lateral bearing behaviour is broadly similar for piles with slenderness ratios of 3, 5 and 8. However, the piles featured with smaller embedment lengths show a larger decrease rate in their lateral capacity, which means the effect of scour should cause more concern on small slenderness ratio monopiles.Geo-engineerin
The Prediction of Biopsychosocial Functioning using Home-Based Accelerometry
No full textPreventive, personalized treatment of biopsychosocial (BPS) functional decline or stagnation in the rehabilitation process requires early prediction of those at risk. Ambulant monitoring of objective physical activity using wearable accelerometers could be a quantitative, noninvasive, and affordable method to gain insight into current and future biopsychosocial functioning.In this retrospective study, Random Forest Regression was used to predict cross-sectional and longitudinal Functional Ambulation Category (FAC) and Six-item Cognitive Impairment Test (6CIT) after hip fracture using ambulatory accelerometry data. Accelerometry data and BPS functional assessments were available of 49 participants of the HIPCARE study, assessing prognostic determinants of outcome after hip fracture in the elderly.Overall, cross-sectional FAC scores three months after hip fracture could be predicted with moderately low error, and categorized regression predictions showed high precision and recall. Cross-sectional 6CIT and both longitudinal regression models underperformed, but categorized regression predictions revealed mixed but more promising precision and recall.It is expected that the predictive performance of models can be improved by increasing participant sample size with balanced samples over population-specific, prevalent ranges of BPS outcome scales and exploring additional machine learning models. In the future, accurate accelerometry-based predictions for individual patients needing rehabilitation could support personalized treatment and improve long-term biopsychosocial functioning.TM30004; 35 ECTSTechnical Medicin
Exploring the enhancement of predictive accuracy for minority classes in travel mode choice models
No full textTransportation systems are pivotal in shaping the economic and social dynamics of contemporary societies, fostering connectivity and opportunities while reducing geographical distances. Despite these benefits, they also contribute to adverse effects such as emissions, congestion, and traffic fatalities. Effectively developing and maintaining transportation infrastructure and services that cater to evolving population needs and align with environmental goals requires accurate forecasting of travel demand. However, due to inherent uncertainty in individuals' behavior and data limitations, forecasting this demand is a complex task.A common limitation often encountered in transport datasets is class imbalance, with regard to the utilization of the different modes. Class imbalance in this context refers to the uneven distribution of samples among the various modes. Modes with a higher number of samples are termed majority modes, while those with fewer instances are labeled as minority modes. The existence of class imbalance within the dataset has the potential to compromise the performance of classifiers, especially for the minority modes, leading to inaccurate forecasts. This, in turn, may result in insufficient investments and provisions for these modes, ultimately having adverse consequences for the population segments that rely on them. Existing studies in the literature have either entirely overlooked or only partially addressed the impact of class imbalance. Recognizing the significance of precise demand predictions and acknowledging the identified gaps within the literature, the primary research question of this study revolves around systematically identifying and addressing the impact of class imbalance in mode choice forecasting.To address the main question, a framework was proposed. This framework encompassed various aspects including a) the measurement of class imbalance within a dataset and the assessment of its impact on classification performance, b) the investigation of other challenging factors coexisting in imbalanced datasets, with a specific focus on class overlap, and c) the proper evaluation of classification performance across classes. As an integral part of this framework, the 'Performance Gap Metric’ was introduced - a metric employed to evaluate the difference in classification performance between the majority and minority classes. Establishing a threshold of 20%, favorable classifier performance was determined when this metric fell below the threshold, signifying the classifier’s equitable treatment of both minority and majority classes. Subsequently, this framework was applied using the ODiN data as a case study to predict mode choices in the Netherlands. Mode choices encompassed car, bike, and transit, with car representing the majority and transit the minority class. Two modeling techniques, namely Random Forest and an MNL model, were employed in conjunction with various sampling techniques, including the SMOTENC, the Neighborhood-based Undersampling, and the Separation scheme...Engineering and Policy Analysi
Critical factors for effective resident participation in neighborhood rehabilitation in Wuhan, China: From the perspectives of diverse stakeholders
No full textResident participation is essential for neighborhood rehabilitation. It requires the active involvement of residents and efficient management by organizers. To improve the effectiveness of resident participation, it is necessary to understand the critical success factors (CSFs) underlying it. However, previous research has examined the critical factors from a single-stakeholder perspective, overlooking potential differences in perceptions among stakeholders with diverse roles and rehabilitation experiences. Based on 30 interviews and 255 questionnaires from six stakeholder groups in Wuhan, China, this study explores how the perception of critical factors for effective resident participation varies among local government, community-based organization, designer, contractor, consulting party, and resident. Thirty-seven factors were identified and compared among the stakeholders. Financial Incentive (for participation organizers) was identified as the most critical factor for effective resident participation, followed by Information Disclosure and Transparency, and Trust. Results from the analysis of variance (ANOVA) show that the six groups differed significantly in the importance of most factors (25/37), especially in Participant Education and Prejudice against the Working Group. Interview results indicate that the COVID-19 pandemic and rehabilitation experience changed stakeholders’ perceived importance of some factors. Specifically, in future RP initiatives, extra emphasis could be placed on Trait and Capacity (of the working group) and Participation-assistance Technologies. Stakeholders regarded these two factors as more critical as their rehabilitation experience accumulated. By understanding stakeholders' conflicting and changing perceptions of effective resident participation, suggestions were proposed to each stakeholder group to fulfill their distinct participation objectives and improve the overall effectiveness of participation practices.Design & Construction ManagementReal Estate Managemen
GLOBGM v1.0: a parallel implementation of a 30 arcsec PCR-GLOBWB-MODFLOW global-scale groundwater model
No full textWe discuss the various performance aspects of parallelizing our transient global-scale groundwater model at 30′′ resolution (30arcsec; °1/41km at the Equator) on large distributed memory parallel clusters. This model, referred to as GLOBGM, is the successor of our 5′ (5arcmin; °1/410km at the Equator) PCR-GLOBWB 2 (PCRaster Global Water Balance model) groundwater model, based on MODFLOW having two model layers. The current version of GLOBGM (v1.0) used in this study also has two model layers, is uncalibrated, and uses available 30′′ PCR-GLOBWB data. Increasing the model resolution from 5′ to 30′′ creates challenges, including increased runtime, memory usage, and data storage that exceed the capacity of a single computer. We show that our parallelization tackles these problems with relatively low parallel hardware requirements to meet the needs of users or modelers who do not have exclusive access to hundreds or thousands of nodes within a supercomputer. For our simulation, we use unstructured grids and a prototype version of MODFLOW 6 that we have parallelized using the message-passing interface. We construct independent unstructured grids with a total of 278 million active cells to cancel all redundant sea and land cells, while satisfying all necessary boundary conditions, and distribute them over three continental-scale groundwater models (168 million - Afro-Eurasia; 77 million - the Americas; 16 million - Australia) and one remaining model for the smaller islands (17 million). Each of the four groundwater models is partitioned into multiple non-overlapping submodels that are tightly coupled within the MODFLOW linear solver, where each submodel is uniquely assigned to one processor core, and associated submodel data are written in parallel during the pre-processing, using data tiles. For balancing the parallel workload in advance, we apply the widely used METIS graph partitioner in two ways: it is straightforwardly applied to all (lateral) model grid cells, and it is applied in an area-based manner to HydroBASINS catchments that are assigned to submodels for pre-sorting to a future coupling with surface water. We consider an experiment for simulating the years 1958-2015 with daily time steps and monthly input, including a 20-year spin-up, on the Dutch national supercomputer Snellius. Given that the serial simulation would require °1/44.5 months of runtime, we set a hypothetical target of a maximum of 16h of simulation runtime. We show that 12 nodes (32 cores per node; 384 cores in total) are sufficient to achieve this target, resulting in a speedup of 138 for the largest Afro-Eurasia model when using 7 nodes (224 cores) in parallel. A limited evaluation of the model output using the United States Geological Survey (USGS) National Water Information System (NWIS) head observations for the contiguous United States was conducted. This showed that increasing the resolution from 5′ to 30′′ results in a significant improvement with GLOBGM for the steady-state simulation when compared to the 5′ PCR-GLOBWB groundwater model. However, results for the transient simulation are quite similar, and there is much room for improvement. Monthly and multi-year total terrestrial water storage anomalies derived from the GLOBGM and PCR-GLOBWB models, however, compared favorably with observations from the GRACE satellite. For the next versions of GLOBGM, further improvements require a more detailed (hydro)geological schematization and better information on the locations, depths, and pumping rates of abstraction wells.Mathematical Physic
Transport of Magma in Granitic Mush Systems; an Example From the Götemar Pluton, Sweden
No full textGranitic magma bodies form in the ephemeral part of magma mush systems and are emplaced by a variety of mechanisms in different tectonic settings. This study investigates how granitic magma emplacement processes and tectonomagmatic interactions assert control over the architecture of mush state pluton-scale magma transport pathways. The 1.45 Ga shallow-crustal Götemar pluton is a 4.5 km diameter circular pluton that consists of three granite units: a coarse-grained red granite, a medium-grained pale to red granite, and fine-grained pale microgranite sheets. We employed geological mapping supported by Anisotropy of Magnetic Susceptibility (AMS) to examine the magmatic and regional tectonic controls on late-stage magma transport in the Götemar granitic magma mush system. Multiple parallel arcuate subhorizontal microgranite and medium-grained granite sheets (from 0.1 to 10s of meters thick) were mapped within the pluton. The arcuate sheets pinch out from the northern part of the pluton toward the SE inferring magma propagation direction. A dominant set of vertical granitic sheets within the granite body strikes NW-SE. The AMS fabrics are contact-parallel in the main medium-grained granite body and indicate inflation. Within the microgranite sheets, the AMS fabrics are parallel to the sheet strike and support a sheet propagation direction to the SE. The Götemar pluton displays a clear link between arcuate (concentric) magma-transporting sheets and concentric strain-partitioning related to the intrusion of medium-grained granite magma. The vertical magma sheet orientations are consistent with an NE-SW extensional stress field that is associated with the extensional back-arc stress regime of the contemporary Hallandian Orogen.Resource Engineerin
Corrigendum to “Estimating bridge criticality due to extreme traffic loads in highway networks” [Eng. Struct. vol. 300, 1 February 2024, 117172] (Engineering Structures (2024) 300, (S0141029623015870), (10.1016/j.engstruct.2023.117172))
No full textThe authors regret the acknowledgments in the published article are incomplete. The complete acknowledgments are as follows: “This research was supported by the Mexican National Council for Science and Technology (CONACYT) under project number 2019-000021-01EXTF-00564 CVU 784544. The authors would like to thank Dr. Andrés Antonio Torres Acosta, Research Professor at the Department of Sustainable and Civil Technologies, School of Engineering and Sciences, Tecnológico de Monterrey for his contributions to this research.” The authors would like to apologise for any inconvenience caused. ____________________________.Hydraulic Structures and Flood RiskIntegral Design & Managemen
Grow With the Flow: Developing a Dynamic Coastal Interface for the Wadden Sea Region
No full textWe live in a world of constant change, driven by human activities that have had an unprecedented impact on our planet’s geology and ecosystems, fundamentally reshaping environments worldwide. Coastal environments, with their complex land-sea, human-nature interactions, are among the most fragile and are constantly under the influence of natural and human processes. For decades, these processes moved in harmony, but as populations grew, so did the demand for resources, land and the development of infrastructure, such as dams, dikes, transport networks and coastal management interventions. The fixation of coastlines and inland systems, driven by contemporary artificial human activity, is an often unintended consequence.The Wadden Sea Region, known for its extensive mudflats, salt marshes and diverse flora and fauna, is an example of how human intervention has had a significant impact on the form and systems of the transition zone between sea and land, or the coastal interface. Over thousands of years, the region has been shaped by the interaction of sea, land and human influences, resulting in a gradient of vital coastal habitats for numerous species and providing many ecosystem services for local and (inter)national economic prosperity. In recent decades, however, human interventions have increasingly altered the region’s coastal interface, largely disrupting the dynamic exchange of energy and materials through land reclamation and infrastructure development. The separation of land and sea has resulted in the loss of the gradual gradients that were once a defining feature of the Wadden Sea Region, along with the region’s identity of ‘living with water’. This has meant the additional loss of vital habitats and ecosystem services provided by the sea for decades, and the overall loss of socio-ecological resilience of the interface system. Now, with the increasing pressures of climate change and human needs on the complex system of the Wadden Sea region, its landscape faces serious challenges now and in the future. A new balance needs to be found between human activities and the conservation and restoration of the unique natural and cultural values of the Wadden Sea Region.The research aims to explore the potential of a new interface framework that restores the landscape gradient between land and sea in harmony with natural processes and cultural values. The intention is to increase the overall social and ecological resilience of the interface system through the development of landscape-based design principles and design interventions, which will be tested at different temporal and spatial scales. The northern Netherlands will serve as a regional test-bed for innovative forms of production and living along the future interface, where the proposed design layout is based on analysis of coastal geomorphological processes, historical practices, landscape structures and existing water structures.Architecture, Urbanism and Building Sciences | Landscape Architectur