bluuebunny/crossref_metadata_2025 huggingface dataset:
Using the Net-Map tool to analyze stakeholder networks in the city region food systems of seven European cities
Authors: Leimkühler Melissa , Specht Kathrin , Schröter Barbara , Wissmann Anna , Iodice Chiara , Fox-Kämper Runrid , Steines Ann-Kristin , Monticone Francesca , Samoggia Antonella , Modarelli Giuseppe Carlo , Reynaud-Desmet Lélia , Curtis Adam , Righini Isabella , D’Ostuni Michele , Ramón Jaime , Amghar Samir , Pascual-Fernández José J.
Published: March 2024

The current global food system is characterized by anonymity in the value chain, global food trade, loss of knowledge about food sources, and a distant producer-consumer relationship. In addition, the negative environmental impacts of the agricultural sector, such as pollution, degradation of soil and water quality, loss of biodiversity, and significant greenhouse gas emissions, make this sector a major driver of climate change. In contrast, the city region food system (CRFS) approach captures the complexity of a food system and its actors at the local level. It aims to meet the requirements of sustainable transformation along the food value chain and offers an alternative approach to the challenges of the global food system. However, the actors and their relationships in CRFS are rarely analyzed. To fill this gap, this study focuses on analyzing CRFSs as networks using the Net-Map tool to study different CRFS in seven European cities (Bologna, Naples, Lansingerland, Tenerife, Oslo, Dortmund, and Romainville). The aim of this paper is to concentrate on the method and to show how the Net-Map tool can effectively support the evaluation of the CRFS by identifying different actor roles, recognizing patterns of relationships. Additionally, the strengths and weaknesses of the network can be assessed by a strengths, weaknesses, opportunities and threats (SWOT) analysis. The paper highlights the limitations, advantages, and practical use of the Net-Map tool and discusses potential transferability to other case studies.
A prospective and consecutive study assessing short-term clinical and radiographic outcomes of Chinese domestically manufactured 3D printing trabecular titanium acetabular cup for primary total hip arthroplasty: evaluation of 236 cases
Authors: Chen Guo , Wang Chen Yi , Ma Zou , Yi Hong Lin , Bi Na Meng , Zhu Wei Jiang , Han Jie , Lu Sha Li , Zhang Shang Shang , Shen Hai , Zhang Wu Hui , Zhang Peng , Si Yan
Published: March 2024

Purpose

We prospectively evaluate the short-term clinical and radiographic outcomes of the only Chinese domestically produced trabecular titanium acetabular cup(3D ACT™ cup) in primary total hip arthroplasty (THA), aiming to provide evidence-based support for its clinical application.

Methods

A total of 236 patients, who underwent primary THA using 3D ACT™ cup in the Department of Joint Surgery at our hospital between January 2017 and June 2019, were included in this study. General patient data, imaging information, functional scores, and complications were collected to evaluate the early clinical efficacy.

Results

All patients were followed up for 33–52 months, with an average of (42.2 ± 9.2) months. At the last follow-up, the preoperative HHS score increased significantly from 43.7 ± 6.8 to 85.6 ± 9.3 points (P < 0.01). Similarly, the preoperative WOMAC scores showed significant improvement from 59.2 ± 5.8 to 13.1 ± 3.5 points (P < 0.01). 92.3% of the patients expressed satisfaction or high satisfaction with the clinical outcome. Furthermore, 87.7% of the acetabular cups were positioned within the Lewinnek safe zone, achieving successful reconstruction of the acetabular rotation center. The cup survival rate at the last follow-up was 100%.

Conclusions

The utilization of the only Chinese domestically manufactured 3D printing trabecular titanium acetabular cup in primary THA demonstrated favorable short-term clinical and radiographic outcomes. The acetabular cup exhibits excellent initial stability, high survival rate, and favorable osseointegration, leading to a significant enhancement in pain relief and functional improvement. In the future, larger sample sizes and multicenter prospective randomized controlled trials will be required to validate the long-term safety and effectiveness of this 3D ACT™ cup.
Impact of a Public Health Emergency on Behavior, Stress, Anxiety and Glycemic Control in Patients With Pancreas or Islet Transplantation for Type 1 Diabetes
Authors: Landstra Cyril P. , Ruissen Merel M. , Regeer Hannah , Nijhoff Michiel F. , Ballieux Bart E. P. B. , van der Boog Paul J. M. , de Vries Aiko P. J. , Huisman Sasja D. , de Koning Eelco J. P.
Published: March 2024

A public health emergency such as the COVID-19 pandemic has behavioral, mental and physical implications in patients with type 1 diabetes (T1D). To what extent the presence of a transplant further increases this burden is not known. Therefore, we compared T1D patients with an islet or pancreas transplant (β-cell Tx; n = 51) to control T1D patients (n = 272). Fear of coronavirus infection was higher in those with β-cell Tx than without (Visual Analogue Scale 5.0 (3.0–7.0) vs. 3.0 (2.0–5.0), p = 0.004) and social isolation behavior was more stringent (45.8% vs. 14.0% reported not leaving the house, p < 0.001). A previous β-cell Tx was the most important predictor of at-home isolation. Glycemic control worsened in patients with β-cell Tx, but improved in control patients (ΔHbA1c +1.67 ± 8.74 vs. −1.72 ± 6.15 mmol/mol, p = 0.006; ΔTime-In-Range during continuous glucose monitoring −4.5% (−6.0%–1.5%) vs. +3.0% (−2.0%–6.0%), p = 0.038). Fewer patients with β-cell Tx reported easier glycemic control during lockdown (10.4% vs. 22.6%, p = 0.015). All T1D patients, regardless of transplantation status, experienced stress (33.4%), anxiety (27.9%), decreased physical activity (42.0%), weight gain (40.5%), and increased insulin requirements (29.7%). In conclusion, T1D patients with β-cell Tx are increasingly affected by a viral pandemic lockdown with higher fear of infection, more stringent social isolation behavior and deterioration of glycemic control.

This trial has been registered in the clinicaltrials.gov registry under identifying number NCT05977205 (URL: https://clinicaltrials.gov/study/NCT05977205).
Integrated Straw Return with Less Power Puddling Improves Soil Fertility and Rice Yield in China’s Cold Regions
Authors: Liu Donghui , Li Pengfei , Wu Wenyu , Yu Shunyao , Naseer Muhammad Rehman , Liu Zhilei , Yu Cailian , Peng Xianlong
Published: March 2024

The rice production system in China is facing challenges, including declining soil fertility and a stagnant rice yield. This study aimed to test whether integrating the return of straw to fields with less power puddling could simultaneously enhance soil fertility and rice yields. Therefore, field experiments were conducted in Heilongjiang Province, a key rice-growing region in China, from 2017 to 2021, using three different planting methods: control group (CK), straw return (SR) and straw return integrated with less power puddling (SR + LP). The results showed that small soil aggregates (particle diameter < 0.25 mm) and soil bulk density were significantly decreased when straw return was integrated with less power puddling. These changes contributed to the preservation of soil structure. Simultaneously, this approach significantly increased soil ammonium nitrogen content from 9.9 to 10.9 mg kg−1, organic matter content from 35.0 to 36.2 g kg−1, available nitrogen content from 140.5 to 147.0 mg kg−1 and available potassium content from 128.6 to 136.8 mg kg−1 at mature stage on average. Consequently, the post-heading stored assimilates accumulation of rice was increased from 6.12 to 6.43 t ha−1, and the nitrogen, phosphorus and potassium accumulation of rice were increased by 7.85 kg ha−1, 1.13 kg ha−1 and 5.68 kg ha−1, respectively. These changes ultimately resulted in a higher 1000 g weight and filled grain rate, providing the foundation for higher yields (an increase from 9.31 t ha−1 to 9.55 t ha−1). Furthermore, this approach also increased the net income for farmers by USD 14 t ha−1. In summary, this study demonstrates that integrating straw return with less power puddling can enhance soil’s nutrient supply and retention capacity. This enhancement may boost the absorption and transportation of nutrients, ultimately establishing the groundwork for higher yields and economic benefits by enhancing the 1000 g weight and filled grain rate. Future research should delve deeper into its applicability across different ecosystems and investigate the yield-increasing mechanisms.
Numerical Simulation Study on Deformation Mechanism of Tunnel–Landslide Orthogonal Systems and Early Warnings of Imminent Sliding
Authors: Mi Meng , Tao Zhigang , Pang Shihui , Liu Keyuan , Qin Ke
Published: March 2024

This paper takes a tunnel through a landslide in Northwest China as an example, constructs a mechanical model of a tunnel–landslide orthogonal system, and explores the deformation mechanism of a tunnel–landslide system and the technology of early warnings of near-slips. Given the problem that it is difficult to accurately monitor the deformation and damage characteristics of the tunnel–landslide system using conventional methods, FLAC3D was used to analyze the deformation mechanism of the tunnel–landslide orthogonal system and numerical simulation of the NPR constant resistance large deformation anchors for the early warning of near-slips. Based on the strength reduction method, by reducing the mechanical parameters of the shear strength of the slip zone and simulating different degrees of landslides, we obtained the change rules of the displacement and the axial force of the NPR constant-resistance large deformation anchor cable in the tunnel–landslide orthogonal system, established the warning mode of the Newtonian force tunnel–landslide orthogonal system, and successfully issued a near-slip warning in actual engineering applications. The above research is of great significance to the stability monitoring and risk assessment of tunnel–landslide systems.
How to Enhance the Diagnosis of Early Stages of Chronic Obstructive Pulmonary Disease (COPD)? The Role of Mobile Spirometry in COPD Screening and Diagnosis—A Systematic Review
Authors: Jankowski Piotr , Mycroft Katarzyna , Górska Katarzyna , Korczyński Piotr , Krenke Rafał
Published: March 2024

COPD is the third leading cause of death worldwide. Its diagnosis can be made with spirometry, which is underused due to its limited accessibility. Portable spirometry holds promise for enhancing the efficacy of COPD diagnoses. The study aimed to estimate COPD prevalence diagnosed with a portable spirometer in high-risk patients and compare it with COPD prevalence based on data from conventional, on-site spirometry. We also evaluated the strategy of a proactive approach to identify COPD in high-risk individuals. We conducted a systematic review of original studies on COPD targeted screening and diagnosis with portable and conventional spirometers selected from 8496 publications initially found in three databases: Cochrane, PubMed, and Embase. The inclusion criteria were met by 28 studies. COPD prevalence evaluated with the use of portable spirometers reached 20.27% and was lower compared to that estimated with the use of conventional spirometers (24.67%). In 11 included studies, postbronchodilator tests were performed with portable spirometers, which enabled a bedside COPD diagnosis. Portable spirometers can be successfully used in COPD targeted screening and diagnosis and thus enhance the detection of COPD at early stages.
Bioinspired Interfacial Friction Control: From Chemistry to Structures to Mechanics
Authors: Kong Yunsong , Ma Shuanhong , Zhou Feng
Published: March 2024

Organisms in nature have evolved a variety of surfaces with different tribological properties to adapt to the environment. By studying, understanding, and summarizing the friction and lubrication regulation phenomena of typical surfaces in nature, researchers have proposed various biomimetic friction regulation theories and methods to guide the development of new lubrication materials and lubrication systems. The design strategies for biomimetic friction/lubrication materials and systems mainly include the chemistry, surface structure, and mechanics. With the deepening understanding of the mechanism of biomimetic lubrication and the increasing application requirements, the design strategy of multi-strategy coupling has gradually become the center of attention for researchers. This paper focuses on the interfacial chemistry, surface structure, and surface mechanics of a single regulatory strategy and multi-strategy coupling approach. Based on the common biological friction regulation mechanism in nature, this paper reviews the research progress on biomimetic friction/lubrication materials in recent years, discusses and analyzes the single and coupled design strategies as well as their advantages and disadvantages, and describes the design concepts, working mechanisms, application prospects, and current problems of such materials. Finally, the development direction of biomimetic friction lubrication materials is prospected.
The Effectiveness of Mindfulness in the Treatment of Methamphetamine Addiction Symptoms: Does Neuroplasticity Play a Role?
Authors: Chmiel James , Malinowska Agnieszka , Rybakowski Filip , Leszek Jerzy
Published: March 2024

Introduction: Methamphetamine is a highly stimulating psychoactive drug that causes life-threatening addictions and affects millions of people around the world. Its effects on the brain are complex and include disturbances in the neurotransmitter systems and neurotoxicity. There are several known treatment methods, but their effectiveness is moderate. It must be emphasised that no drugs have been approved for treatment. For this reason, there is an urgent need to develop new, effective, and safe treatments for methamphetamine. One of the potential treatments is mindfulness meditation. In recent years, this technique has been researched extensively in the context of many neurological and psychiatric disorders. Methods: This review explores the use of mindfulness in the treatment of methamphetamine addiction. Searches were conducted in the PubMed/Medline, Research Gate, and Cochrane databases. Results: Ten studies were identified that used mindfulness-based interventions in the treatment of methamphetamine addiction. The results show that mindfulness is an effective form of reducing hunger, risk of relapses, stress indicators, depression, and aggression, alone or in combination with transcranial direct current stimulation (tDCS). Mindfulness also improved the cognitive function in addicts. The included studies used only behavioural measures. The potential mechanisms of mindfulness in addiction were explained, and it was proposed that it can induce neuroplasticity, alleviating the symptoms of addiction. Conclusions: Evidence from the studies suggest that mindfulness may be an effective treatment option for methamphetamine addiction, used alone or in combination with tDCS. However, further high-quality research is required to establish the role of this treatment option in this field. The use of neuroimaging and neurophysiological measures is fundamental to understand the mechanisms of mindfulness.
Wood-Derived Graphite: A Sustainable and Cost-Effective Material for the Wide Range of Industrial Applications
Authors: Kim Young Soon , Hanif Md. Abu , Song Hyeonjin , Kim Sungeun , Cho Yonu , Ryu Seung-Kon , Kim Hong Gun
Published: March 2024

The study explored the graphitization of wood through two distinct methods: a high-temperature approach at 2400 °C and a low-temperature technique at 1400 °C using a catalyst. The graphitization properties were assessed by conducting thermal experiments at various temperatures (1100 °C, 1400 °C, 1800 °C, 2000 °C, and 2400 °C), both with and without a catalyst. The development of graphite lattices was quantitatively analyzed using an array of techniques: X-ray diffractometer (XRD), Raman spectroscopy, high-resolution transmission electron microscopy (HR-TEM), and Fourier transform infrared spectroscopy (FTIR). The XRD analysis highlighted temperature-dependent changes in lattice parameters (d002, La, and Lc), while Raman spectroscopy tracked alterations in the D to G peak ratio (D/G) with temperature. An increase in temperature is correlated with a rise in the number of graphene layers and the degree of graphitization. Notably, the process of graphite lattice formation varied across the experimental temperature spectrum. The use of a catalyst resulted in a reduced d002 spacing, signifying an enhanced degree of graphitization. Moreover, the catalyst promoted a consistent and smooth graphitization process throughout the heating stages. In contrast, graphitization without a catalyst occurred at higher temperatures, specifically between 1800 °C and 2000 °C, with the d002 value stabilizing around 0.338 nm. The catalyst proved instrumental in transforming the initial structure into well-ordered graphite at lower temperatures. This investigation underscores the potential and benefits of employing a catalyst to generate high-quality graphite from wood at reduced temperatures, paving the way for sustainable and economically viable applications of this material.
Results of Surgical Treatment of Occult Spinal Dysraphisms—A Single Centre Experience
Authors: Spazzapan Peter , Velnar Tomaz , Perosa Nina , Porcnik Andrej , Prestor Borut
Published: March 2024

Occult spinal dysraphisms (OSDs) are caused by various defects in the embryogenesis of the spinal cord and represent an obstacle to the ascent of the conus, which allows the conus to pass from the lower levels of the spinal canal to the final position between L1 and L2 during normal foetal life. When an OSD tethers the spinal cord at the lower levels, it can lead to neurological symptoms, better known as tethered cord syndrome. Surgical treatment of OSD is primarily aimed at untethering the spinal cord. In asymptomatic patients, this can protect against the long-term development of neurological deficits. In symptomatic patients, this can halt or limit the progression of existing symptoms. The aim of this study is to examine all paediatric and adult patients diagnosed with OSD and treated in the Department of Neurosurgery at the University Medical Centre Ljubljana during the 5-year period of 2016–2021. All patients diagnosed with OSD during this period were included in the study. Patient characteristics, treatment modalities and outcomes were studied with the aim of describing the differences between the paediatric and adult population and defining the rationality of treating these pathological conditions. We included in the study 52 patients with 64 occult dysraphic lesions. Adults (>18 years old) represented 15/52 (28.8%) of all patients, while 37/52 (71.8%) were children. The most common OSDs were conus lipomas, followed by dermal sinus tracts, filum terminale lipomas and split cord malformations. Surgical treatment was performed in 35/52 (67.3%) cases, while conservative management was chosen in 17/52 (32.6%) cases. The preoperative presence of symptoms was statistically higher in adults than in children (p = 0.0098). Surgery on complex spinal cord lipomas was statistically related to a higher rate of postoperative neurological complications (p = 0.0002). The treatment of OSD is complex and must be based on knowledge of the developmental anomalies of the spine and spinal cord. Successful surgical treatment relies on microsurgical techniques and the use of neuromonitoring. Successful treatment can prevent or limit the occurrence of neurological problems.
Research on A Global Path-Planning Algorithm for Unmanned Arial Vehicle Swarm in Three-Dimensional Space Based on Theta*–Artificial Potential Field Method
Authors: Zhao Wen , Li Liqiao , Wang Yingqi , Zhan Hanwen , Fu Yiqi , Song Yunfei
Published: March 2024

The current challenge in drone swarm technology is three-dimensional path planning and adaptive formation changes. The traditional A* algorithm has limitations, such as low efficiency, difficulty in handling obstacles, and numerous turning points, which make it unsuitable for complex three-dimensional environments. Additionally, the robustness of drone formations under the leader–follower mode is low, and effectively handling obstacles within the environment is challenging. To address these issues, this study proposes a virtual leader mode for drone formation flight and introduces a new Theta*–APF method for three-dimensional space drone swarm path planning. This algorithm optimizes the A* algorithm by transforming it into an omnidirectional forward Theta* algorithm. It also enhances the heuristic function by incorporating artificial potential field methods in a three-dimensional environment. Formation organization and control of UAVs is achieved using speed-control modes. Compared to the conventional A* algorithm, the Theta*–APF algorithm reduces the search time by about 60% and the trip length by 10%, in addition to the safer flight of the UAV formation, which is subject to artificial potential field repulsion by about 42%.
Non-Projective Two-Weight Codes
Authors: Kurz Sascha
Published: March 2024

It has been known since the 1970’s that the difference of the non-zero weights of a projective Fq-linear two-weight code has to be a power of the characteristic of the underlying field. Here, we study non-projective two-weight codes and, e.g., show the same result under mild extra conditions. For small dimensions we give exhaustive enumerations of the feasible parameters in the binary case.
The Mechanism of the Semi-Transparent Coverings Affecting the Power Generation Capacity of the Photovoltaic Module and Array
Authors: Li Yingfeng , Liu Zhihan , Liu Dongxue , Wang Zixuan , Gong Yongshuai , Gao Wenxiang , Liu Yingjian , An Jiayuan , Li Meicheng
Published: March 2024

Shading on photovoltaic (PV) modules due to shadows, covering, dust, etc., usually characterized as semi-transparent, will significantly affect the power generation capacity. No systematic study has considered the impact of semi-transparent coverings on the power generation capacity of PV modules. This paper covers a single cell in the PV module using a covering with a transmittance of 18.55% and systematically investigates its impact on the power generation capacity. The open-circuit voltage (Voc) of the PV module is nearly unaffected by semi-transparent coverings because the covered cell can be considered as working at a lower irradiance and thus can output a voltage close to that of the uncovered cell. The short-circuit current (Isc) is significantly affected by coverings because it is co-contributed by the photocurrent (evaluated based on the covering ratio R and transmittance) and the reverse bias current ΔIsc (the covered cell is in a reverse bias state). The ΔIsc increases with R because more charge accumulates at the bi-ends of the covered cell; but, it decreases at full covering, which implies that in a partially covered case the uncovered part contributes more to ΔIsc than the covered part. The fill factor (FF) of the PV module first increases and then decreases with R, as the equivalent resistance of the covered cell increases rapidly with R, which replaces the wire resistance in dominating the series resistance of the PV module when R > 0.6. This work is of great theoretical significance in analyzing the output characteristics of PV modules under real conditions.
Navigating the Implementation of Tax Credits for Natural-Gas-Based Low-Carbon-Intensity Hydrogen Projects
Authors: Lin Ning , Xu Liying
Published: March 2024

This paper delves into the critical role of tax credits, specifically Sections 45Q and 45V, in the financing and economic feasibility of low-carbon-intensity hydrogen projects, with a focus on natural-gas-based hydrogen production plants integrated with carbon capture and storage (CCS). This study covers the current clean energy landscape, underscoring the importance of low-carbon hydrogen as a key component in the transition to a sustainable energy future, and then explicates the mechanics of the 45Q and 45V tax credits, illustrating their direct impact on enhancing the economic attractiveness of such projects through a detailed net present value (NPV) model analysis. Our analysis reveals that the application of 45Q and 45V tax credits significantly reduces the levelized cost of hydrogen production, with scenarios indicating a reduction in cost ranging from USD 0.41/kg to USD 0.81/kg of hydrogen. Specifically, the 45Q tax credit demonstrates a slightly more advantageous impact on reducing costs compared to the 45V tax credit, underpinning the critical role of these fiscal measures in enhancing project returns and feasibility. Furthermore, this paper addresses the inherent limitations of utilizing tax credits, primarily the challenge posed by the mismatch between the scale of tax credits and the tax liability of the project developers. The concept and role of tax equity investments are discussed in response to this challenge. These findings contribute to the broader dialogue on the financing of sustainable energy projects, providing valuable insights for policymakers, investors, and developers in the hydrogen energy sector. By quantifying the economic benefits of tax credits and elucidating the role of tax equity investments, our research supports informed decision-making and strategic planning in the pursuit of a sustainable energy future.
A Novel Methodology for Developing an Advanced Energy-Management System
Authors: Gheorghiu Cristian , Scripcariu Mircea , Tanasiev Gabriela Nicoleta , Gheorghe Stefan , Duong Minh Quan
Published: March 2024

Current targets, which have been set at both the European and the international level, for reducing environmental impacts and moving towards a sustainable circular economy make energy efficiency and digitization key elements of all sectors of human activity. The authors proposed, developed, and tested a complex methodology for real-time statistical analysis and forecasting of the following main elements contributing to the energy and economic performance of an end user: energy performance indicators, power quality indices, and the potential to implement actions to improve these indicators, in an economically sustainable manner, for the end user. The proposed methodology is based on machine learning algorithms, and it has been tested on six different energy boundaries. It was thus proven that, by implementing an advanced energy management system (AEMS), end users can achieve significant energy savings and thus contribute to the transition towards environmental sustainability.
Improvement in Atrioventricular Conduction Using Cardioneuroablation Performed Immediately after Pulmonary Vein Isolation
Authors: Zarębski Łukasz , Futyma Piotr , Sethia Yashvi , Futyma Marian , Kułakowski Piotr
Published: March 2024

In patients with atrial fibrillation (AF) recurrences after pulmonary vein isolation (PVI), concomitant treatment using anti arrhythmic drugs (AADs) can lead to clinical success. However, patients with atrioventricular (AV) block may not be good candidates for concomitant AAD therapy due to the risk of further worsening of conduction abnormalities. Cardioneuroablation (CNA), as an adjunct to PVI, may offer a solution to this problem. We present a case of a 74-year-old male with paroxysmal AF and first degree AV block in whom CNA following PVI led to PR normalization. The presented case describes an example of CNA utilization in patients with AF undergoing PVI who have concomitant problems with AV conduction and shows that CNA can be sometimes useful in older patients with functional AV block.
Infant Acute Lymphoblastic Leukemia—New Therapeutic Opportunities
Authors: Kulczycka Marika , Derlatka Kamila , Tasior Justyna , Sygacz Maja , Lejman Monika , Zawitkowska Joanna
Published: March 2024

Infant acute lymphoblastic leukemia (Infant ALL) is a kind of pediatric ALL, diagnosed in children under 1 year of age and accounts for less than 5% of pediatric ALL. In the infant ALL group, two subtypes can be distinguished: KMT2A-rearranged ALL, known as a more difficult to cure form and KMT2A- non-rearranged ALL with better survival outcomes. As infants with ALL have lesser treatment outcomes compared to older children, it is pivotal to provide novel treatment approaches. Progress in the development of molecularly targeted therapies and immunotherapy presents exciting opportunities for potential improvement. This comprehensive review synthesizes the current literature on the epidemiology, clinical presentation, molecular genetics, and therapeutic approaches specific to ALL in the infant population.
Identifying Residues for Substrate Recognition in Human GPAT4 by Molecular Dynamics Simulations
Authors: Liu Yulan , Xu Yunong , Xu Yinuo , Zhao Zhihao , Cheng Gui-Juan , Ren Ruobing , Chiang Ying-Chih
Published: March 2024

Glycerol-3-phosphate acyltransferase (GPAT) catalyzes the first step in triacylglycerol synthesis. Understanding its substrate recognition mechanism may help to design drugs to regulate the production of glycerol lipids in cells. In this work, we investigate how the native substrate, glycerol-3-phosphate (G3P), and palmitoyl-coenzyme A (CoA) bind to the human GPAT isoform GPAT4 via molecular dynamics simulations (MD). As no experimentally resolved GPAT4 structure is available, the AlphaFold model is employed to construct the GPAT4–substrate complex model. Using another isoform, GPAT1, we demonstrate that once the ligand binding is properly addressed, the AlphaFold complex model can deliver similar results to the experimentally resolved structure in MD simulations. Following the validated protocol of complex construction, we perform MD simulations using the GPAT4–substrate complex. Our simulations reveal that R427 is an important residue in recognizing G3P via a stable salt bridge, but its motion can bring the ligand to different binding hotspots on GPAT4. Such high flexibility can be attributed to the flexible region that exists only on GPAT4 and not on GPAT1. Our study reveals the substrate recognition mechanism of GPAT4 and hence paves the way towards designing GPAT4 inhibitors.
Integrated Computational Approaches for Drug Design Targeting Cruzipain
Authors: Parvez Aiman , Lee Jeong-Sang , Alam Waleed , Tayara Hilal , Chong Kil To
Published: March 2024

Cruzipain inhibitors are required after medications to treat Chagas disease because of the need for safer, more effective treatments. Trypanosoma cruzi is the source of cruzipain, a crucial cysteine protease that has driven interest in using computational methods to create more effective inhibitors. We employed a 3D-QSAR model, using a dataset of 36 known inhibitors, and a pharmacophore model to identify potential inhibitors for cruzipain. We also built a deep learning model using the Deep purpose library, trained on 204 active compounds, and validated it with a specific test set. During a comprehensive screening of the Drug Bank database of 8533 molecules, pharmacophore and deep learning models identified 1012 and 340 drug-like molecules, respectively. These molecules were further evaluated through molecular docking, followed by induced-fit docking. Ultimately, molecular dynamics simulation was performed for the final potent inhibitors that exhibited strong binding interactions. These results present four novel cruzipain inhibitors that can inhibit the cruzipain protein of T. cruzi.
Effect of the Printing Angle on the Microstructure and Tensile Performance of Iron-Reinforced Polylactic Acid Composite Manufactured Using Fused Filament Fabrication
Authors: Guessasma Sofiane , Belhabib Sofiane
Published: March 2024

This work emphasizes an innovative approach utilizing 3D imaging technology based on synchrotron radiation to assess the microstructure of second-phase iron particles and the porous structure within 3D-printed PLA/magnetic iron composites at different printing angles. The study examines how these observations relate to the material’s ductility when processed using fused filament fabrication. In particular, this study examines the impact of one processing parameter, specifically the printing angle, on the microstructure and mechanical behaviour of a polylactic acid (PLA)–iron (PLI) composite designed for magnetic actuation. Fused filament fabrication is employed to produce PLI tensile specimens, with varied printing angles to create different layups. X-ray microtomography is utilized to analyse the microstructure, while tensile mechanical properties are evaluated for all composites, with findings discussed in relation to printing angle conditions. Scanning Electron Microscopy is used to examine the fractography of broken specimens. Results indicate that the printing angle significantly influences the tensile properties and mechanical anisotropy of 3D-printed PLI composites, with an optimal 45°/45° layup enhancing tensile performance. These findings suggest that 3D-printed PLI composites offer a cost-efficient means of producing bio-sourced, light-adaptive materials with intricate magnetic actuation capabilities. By quantifying the modulation of mechanical properties based on printing parameters that influence microstructural arrangement, the research sheds light on a novel aspect of composite material characterization.
Fast Ray-Tracing-Based Precise Localization for Internet of Underwater Things without Prior Acknowledgment of Target Depth
Authors: Huang Wei , Meng Kaitao , Sun Wenzhou , Shu Jianxu , Xu Tianhe , Zhang Hao
Published: March 2024

Underwater localization is one of the key techniques for positioning, navigation, timing (PNT) services that could be widely applied in disaster warning, underwater rescues and resource exploration. One of the reasons why it is difficult to achieve accurate positioning for underwater targets is due to the influence of uneven distribution of underwater sound velocity. The current sound-line correction positioning method mainly aims at scenarios with known target depth. However, for nodes that are non-cooperative nodes or lack depth information, sound-line tracking strategies cannot work well due to non-unique positional solutions. To solve this problem, we propose an iterative ray tracing 3D underwater localization (IRTUL) method for stratification compensation. To demonstrate the feasibility of fast stratification compensation, we first derive the signal path as a function of initial |grazing angle, and then prove that the signal propagation time and horizontal propagation distance are monotonic functions of the initial grazing angle, which guarantees the fast achievement of ray tracing. Simulation results indicate that IRTUL has the most significant correction effect in the depth direction, and the average accuracy has been improved by about 3 m compared to a localization model with constant sound velocity.
Identification of Wind Load Exerted on the Jacket Wind Turbines from Optimally Placed Strain Gauges Using C-Optimal Design and Mathematical Model Reduction
Authors: Zhu Fan , Zhang Meng , Ma Fuxuan , Li Zhihua , Qu Xianqiang
Published: March 2024

Wind turbine towers experience complex dynamic loads during actual operation, and these loads are difficult to accurately predict in advance, which may lead to inaccurate structural fatigue and strength assessment during the structural design phase, thereby posing safety risks to the wind turbine tower. However, online monitoring of wind loads has become possible with the development of load identification technology. Therefore, an identification method for wind load exerted on wind turbine towers was developed in this study to estimate the wind loads using structural strain, which can be used for online monitoring of wind loads. The wind loads exerted on the wind turbine tower were simplified into six equivalent concentrated forces on the topside of the tower, and the initial mathematical model for wind load identification was established based on dynamic load identification theory in the frequency domain, in which many candidate sensor locations and directions were considered. Then, the initial mathematical model was expressed as a linear system of equations. A numerical example was used to verify the accuracy and stability of the initial mathematical model for the wind load identification, and the identification results indicate that the initial mathematical model combined with the Moore–Penrose inverse algorithm can provide stable and accurate reconstruction results. However, the initial mathematical model uses too many sensors, which is not conducive to engineering applications. Therefore, D-optimal and C-optimal design methods were used to reduce the dimension of the initial mathematical model and determine the location and direction of strain gauges. The C-optimal design method adopts a direct optimisation search strategy, while the D-optimal design method adopts an indirect optimisation search strategy. Then, four numerical examples of wind load identification show that dimensionality reduction of the mathematical model leads to high accuracy, in which the C-optimal design algorithm provides more robust identification results. Moreover, the fatigue damage calculated based on the load identification wind loads closely approximates that derived from finite element simulation wind load, with a relative error within 6%. Therefore, the load identification method developed in this study offers a pragmatic solution for the accurate acquisition of the actual wind load of a wind turbine tower.
Study of Velocity Changes Induced by Posidonia oceanica Surrogate and Sediment Transport Implications
Authors: Astudillo-Gutierrez Carlos , Rabionet Iván Cáceres , Garcia Vicente Gracia , Pedrico Joan Pau Sierra , Conejo Agustín Sánchez-Arcilla
Published: March 2024

An analysis of the interactions between wave-induced velocities and seagrass meadows has been conducted based on the large-scale CIEM wave flume data. Incident irregular wave trains act on an initial 1:15 sand beach profile with measurement stations from the offshore of a surrogate meadow until the outer breaking zone, after crossing the seagrass meadow. The analysis considers variability and peaks of velocities, together with their skewness and asymmetry, to determine the effects of the seagrass meadow on the near bed sediment transport. Velocity variability was characterized by the standard deviation, and the greatest changes were found in the area right behind the meadow. In this zone, the negative peak velocities decreased by up to 20.3%, and the positive peak velocities increased by up to 11.7%. For more onshore positions, the negative and positive peak velocities similarly decreased and increased in most of the studied stations. A progressive increase in skewness as the waves passed through the meadow, together with a slight decrease in asymmetry, was observed and associated with the meadow effect. Moving shoreward along the profile, the values of skewness and asymmetry increased progressively relative to the position of the main sandbar. The megaripple-like bedforms appeared earlier when the meadow was present due to the higher skewness, showing a belated development in the layout without the meadow, when skewness increased further offshore due to the proximity of the breaker sandbar. To assess the sediment transport capacity of a submerged meadow, the SANTOSS formula was applied, showing that in front of the meadow, there was a higher sediment transport capacity, whereas behind the meadow, that capacity could be reduced by up to 41.3%. In addition, this formula was able to produce a suitable estimate of sediment transport across the profile, although it could not properly estimate the sediment volumes associated with the bedforms generated in the profile.
Modelling and Optimization of Machined Surface Topography in Ball-End Milling Process
Authors: Wang Renwei , Zhao Bin , Tan Dingzhong , Wan Wenjie
Published: March 2024

In order to optimize machined surface topography, this paper presents a novel algorithm for simulating the surface topography and predicting the surface roughness of a ball-end milling process. First, a discrete workpiece model was developed using the Z-map method, and the swept surface of a cutter edge was represented using triangular approximation. The workpiece surface was updated (i.e., material removal process) using the intersection between the vertical reference line and the triangular facet under a cutting judgement. Second, the proposed algorithm was verified by comparing the simulated 3D surface topography as well as 2D surface profile and average roughness (Sa) with experimental measurements. Then, numerical simulation examples planed by the Box–Behnken design methods were carried out to investigate the Sa in the ball-end milling operation. The correlations of Sa and cutting parameters were represented by a response surface reduced quadratic model based on the ANOVA results. Finally, the feed per tooth, radial depth of cut, and tilt and lead angles were optimized for improving the machining efficiency under the Sa constraints. This study presents an effective method for simulating surface topography and predicting the Sa to optimize the cutting parameters during ball-end milling process.
Supercritical Operation of Bearingless Cross-Flow Fan
Authors: Bagaric Ivana , Steinert Daniel , Nussbaumer Thomas , Kolar Johann W.
Published: March 2024

This paper presents a decoupled bearingless cross-flow fan (CFF) that operates at a supercritical speed, thereby increasing the maximum achievable rotational speed and fluid dynamic power. In magnetically levitated CFF rotors, the rotational speed and fan performance are limited by the bending resonance frequency. This is primarily defined by the low mechanical bending stiffness of the CFF blades, which are optimised for fluid dynamic performance, and the heavy rotor magnets on both rotor sides, which add significant mass but a minimal contribution to the overall rotor stiffness. This results in detrimental deformations of the CFF blades in the vicinity of the rotor bending resonance frequency; hence, the CFF is speed-limited to subcritical rotational speeds. The novel CFF rotor presented in this study features additional mechanical decoupling elements with low bending stiffness between the fan blades and the rotor magnets. Thus, the unbalance forces primarily deform the soft decoupling elements, which enables them to pass resonances without CFF blade damage and allows rotor operation in the supercritical speed region due to the self-centring effect of the rotor. The effects of the novel rotor design on the rotor dynamic behaviour are investigated by means of a mass-spring-damper model. The influence of different decoupling elements on the magnetic bearing is experimentally tested and evaluated, from which an optimised decoupled CFF rotor is derived. The final prototype enables a stable operation at 7000 rpm in the supercritical speed region. This corresponds to a rotational speed increase of 40%, resulting in a 28% higher, validated fluid flow and a 100% higher static pressure compared to the previously presented bearingless CFF without decoupling elements.
Towards a Generalized Cayley–Dickson Construction through Involutive Dimagmas
Authors: Martins-Ferreira Nelson , Perdigão Rui A. P.
Published: March 2024

A generalized construction procedure for algebraic number systems is hereby presented. This procedure offers an efficient representation and computation method for complex numbers, quaternions, and other algebraic structures. The construction method is then illustrated across a range of examples. In particular, the novel developments reported herein provide a generalized form of the Cayley–Dickson construction through involutive dimagmas, thereby allowing for the treatment of more general spaces other than vector spaces, which underlie the associated algebra structure.
Neural Machine Translation with CARU-Embedding Layer and CARU-Gated Attention Layer
Authors: Im Sio-Kei , Chan Ka-Hou
Published: March 2024

The attention mechanism performs well for the Neural Machine Translation (NMT) task, but heavily depends on the context vectors generated by the attention network to predict target words. This reliance raises the issue of long-term dependencies. Indeed, it is very common to combine predicates with postpositions in sentences, and the same predicate may have different meanings when combined with different postpositions. This usually poses an additional challenge to the NMT study. In this work, we observe that the embedding vectors of different target tokens can be classified by part-of-speech, thus we analyze the Natural Language Processing (NLP) related Content-Adaptive Recurrent Unit (CARU) unit and apply it to our attention model (CAAtt) and embedding layer (CAEmbed). By encoding the source sentence with the current decoded feature through the CARU, CAAtt is capable of achieving translation content-adaptive representations, which attention weights are contributed and enhanced by our proposed L1expNx normalization. Furthermore, CAEmbed aims to alleviate long-term dependencies in the target language through partial recurrent design, performing the feature extraction in a local perspective. Experiments on the WMT14, WMT17, and Multi30k translation tasks show that the proposed model achieves improvements in BLEU scores and enhancement of convergence over the attention-based plain NMT model. We also investigate the attention weights generated by the proposed approaches, which indicate that refinement over the different combinations of adposition can lead to different interpretations. Specifically, this work provides local attention to some specific phrases translated in our experiment. The results demonstrate that our approach is effective in improving performance and achieving a more reasonable attention distribution compared to the state-of-the-art models.
Displacement Prediction Method for Bank Landslide Based on SSA-VMD and LSTM Model
Authors: Xie Xuebin , Huang Yingling
Published: March 2024

Landslide displacement prediction is of great significance for the prevention and early warning of slope hazards. In order to enhance the extraction of landslide historical monitoring signals, a landslide displacement prediction method is proposed based on the decomposition of monitoring data before prediction. Firstly, based on the idea of temporal addition, the sparrow search algorithm (SSA) coupled with the variational modal decomposition (VMD) algorithm is used to decompose the total landslide displacement into trend item, periodic item and random item; then, the displacement values of the subitems are fitted by using the long and short-term memory (LSTM) neural network, and the predicted cumulative landslide displacement is obtained by adding up the predicted values of the three subsequences. Finally, the historical measured data of the Shuping landslide is taken as an example. Considering the effects of seasonal rainfall and reservoir water level rise and fall, the displacement of this landslide is predicted, and the prediction results of other traditional models are compared. The results show that the landslide displacement prediction model of SSA-VMD coupled with LSTM can predict landslide displacement more accurately and capture the characteristics of historical signals, which can be used as a reference for landslide displacement prediction.