bluuebunny/crossref_metadata_2025 huggingface dataset:
Adjusting the energy profile for CH–O interactions leads to improved stability of RNA stem-loop structures in MD simulations
Authors: Raguette Lauren , Gunasekera Sarah , Ventura Diaz Rebeca , Aminov Ethan , Linzer Jason , Parwana Diksha , Wu Qin , Simmerling Carlos , Nagan Maria
Published: April 2024

The role of RNA in biology continues to grow but insight into important aspects of RNA behavior is lacking, such as dynamic structural ensembles in different environments, how flexibility is coupled to function, and how function might be modulated by small molecule binding. In the case of proteins, much progress in these areas has been made by complementing experiments with atomistic simulations, but RNA simulation methods and force fields are less mature. It remains challenging to generate stable RNA simulations, even for small systems where well-defined, thermostable structures have been established by experiments. Many different aspects of RNA energetics have been adjusted in force fields, seeking improvements that are transferable across a variety of RNA structural motifs. In this work, we explore the role of weak CH…O interactions, which are ubiquitous in RNA structure but have received less attention in RNA force field development. By comparing data extracted from high-resolution RNA crystal structures to energy profiles from quantum mechanics and force field calculations, we demonstrate that CH…O interactions are overly repulsive in the widely-used Amber RNA force fields. We developed a simple, targeted adjustment of CH…O repulsion that leaves the remainder of the force field unchanged. We then tested the standard and modified force fields using MD simulations with explicit water and salt, amassing over 300 μsec of data for multiple RNA systems containing important features such as presence of loops, base stacking interactions as well as canonical and non-canonical base pairing. Our results demonstrate that the standard force fields lead to reproducible unfolding of the NMR-based structures, as has been reported by others. Including our CH…O adjustment in an otherwise identical protocol dramatically improves the outcome, leading to stable simulations for all RNA systems tested.
A versatile fabrication route for screening block copolymer membranes for bioprocessing
Authors: Meng Ke , Alvarez-Fernandez Alberto , Guldin Stefan , Bracewell Daniel G.
Published: April 2024

Traditional polyethersulfone (PES) filters, widely used for sterile, viral and ultrafil- tration often exhibit limited selectivity-permeability due to the heterogenous pore size distribution. Such limitations have sparked interest in developing novel isoporous mem- brane materials and fabrication techniques to overcome the selectivity-permeability upper bound. Among several promising candidates, block copolymer membranes pro- duced via the self-assembly and non-solvent induced phase separation (SNIPS) method offer distinct advantages, such as customisable pore size, narrow dispersity, high poros- ity and mechanical flexibility. However, achieving the desired structure formation in SNIPS remains a complex optimisation procedure, rendering this approach unsuitable for the rapid screening of new block copolymer candidates. This study explores a direct spin coating method to fabricate a poly(styrene)-block- poly(methyl methacrylate) (PS-b-PMMA) thin film composite membrane, integrating a block copolymer layer with rigid anodic aluminium oxide (AAO) support. The pro- cess involves depositing the polymer solution onto a water-filled AAO substrate via spin coating. Compared with the SNIPS method, this fabrication process greatly re- duces the complexity of optimisation to yield an isoporous membrane structure for filtration purposes. We present this approach as a straightforward and reliable plat- form method for the rapid screening and evaluation of block copolymer membranes in their initial development stages. When compared to commercial PES membranes with similar molecular weight cut-offs, these novel PS-b-PMMA thin film composite membranes showed similar transmission rates for Bovine Serum Albumin and a Mon- oclonal Antibody while providing a 9 fold enhancement in Thyroglobulin rejection. This indicates a superior performance in terms of cut-off precision. The membranes demonstrate potential for the removal of viruses and antibody aggregates in the down- stream processing of monoclonal antibody production, which could reduce the burden of chromatographic polishing steps. An advance which offers promise for improving efficiency and reducing costs in biopharmaceutical manufacturing.
Alzheimer's Disease: Exploring the Landscape of Cognitive Decline
Authors: Tenchov Rumiana , Sasso Janet , Zhou Qiongqiong Angela
Published: April 2024

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline, memory loss, and impaired daily functioning. The pathology of AD is marked by the accumulation of amyloid-beta plaques and tau protein tangles in brain, along with neuroinflammation and synaptic dysfunction. Genetic factors, such as mutations in APP, PSEN1, and PSEN2 genes, as well as APOE ε4 allele, contribute to increased risk of acquiring AD. Currently available treatments provide symptomatic relief but do not halt disease progression. Research efforts are focused on developing disease-modifying therapies that target the underlying pathological mechanisms of AD. Advances in identification and validation of reliable biomarkers for AD hold great promise for enhancing early diagnosis, monitoring disease progression, and assessing treatment response in clinical practice, in effort to alleviate the burden of this devastating disease. In this paper, we analyze data from the CAS Content Collection to summarize the research progress in Alzheimer’s disease. We examine the publication landscape in effort to provide insights into current knowledge advances and developments. We also review the most discussed and emerging concepts and assess the strategies to combat the disease. We explore the genetic risk factors, pharmacological targets, and comorbid diseases. Finally, we inspect clinical applications of products against AD with their development pipelines and efforts for drug repurposing. The objective of this review is to provide a broad overview of the evolving landscape of current knowledge regarding AD, to outline challenges, and evaluate growth opportunities to further efforts in combating the disease.
Anisotropic porosity and interface synergy enhanced gas permselectivity in heterolayer metal-organic framework membrane
Authors: Kundu Susmita , Maity Tanmoy , Panda Suvendu , Haldar Ritesh
Published: April 2024

The pursuit of sustainable, carbon-free separation technology hinges on the efficient separation of gas mixtures with high separation factors and flow rates, i.e. high permselectivity. However, achieving this objective is arduous due to the meticulous engineering at the angstrom scale and intricate chemical manipulation required to design the pores within membranes. To address this challenge, a proof-of-concept for an anisotropic porous membrane has been devised. Employing a meticulous step-by-step methodology, two distinct porous metal-organic frameworks (MOFs) are integrated to form a monolithic anisotropic membrane. By harnessing pore anisotropy (3.4 to 6 Å) aligned with the gas permeation direction and a unique interface characterized by cross-linked pores derived from the two distinct MOFs, this membrane transcends the performance limitations inherent in the individual MOF membranes. This approach not only sheds light on the unprecedented heterolayer membrane design strategy but also elucidates the intricate CO2/N2 permselectivity relationship inherent in the interface structure.
Electron Transfer Dynamics at Dye-Sensitized SnO2/TiO2 Core-Shell Electrodes in Aqueous/Nonaqueous Electrolyte Mixtures
Authors: Xiao Langqiu , Spies Jacob , Sheehan Colton , Zeng Zichen , Gao Yunhan , Gao Tianyue , Ehrlacher Annika , Zuerch Michael , Brudvig Gary , Mallouk Thomas
Published: April 2024

The dynamics and efficiency of photoinduced electron transfer were measured at dye-sensitized photoanodes in aqueous (acetate buffer), nonaqueous (acetonitrile), and mixed solvent electrolytes by nanosecond transient spectroscopy (TAS) and ultrafast optical-pump terahertz-probe spectroscopy (OPTP). Higher injection efficiencies were found in mixed solvent electrolytes for dye-sensitized SnO2/TiO2 core/shell electrodes, whereas the injection efficiency of dye-sensitized TiO2 electrodes decreased with the increasing acetonitrile concentration. The trend in injection efficiency for the TiO2 electrodes was consistent with the solvent-dependent trend in the semiconductor flat-band potential. Photoinduced electron injection in core-shell electrodes has been understood as a two-step process involving ultrafast electron trapping in the TiO2 shell followed by slower electron transfer to the SnO2 core. The driving force for shell-to-core electron transfer increases as the flat band potential of TiO2 shifts negatively with increasing concentration of acetonitrile. In acetonitrile-rich electrolytes, despite the larger driving force, electron injection is suppressed. Interestingly, a net negative photoconductivity in the SnO2 core is observed in mixed solvent electrolytes by OPTP. We hypothesize that an electric field is formed across the TiO2 shell from the oxidized dye molecules after injection. The intrinsic conduction band electrons in SnO2 are trapped at the core-shell interface by the electric field, resulting in a negative photoconductivity transient. The overall electron injection efficiency of the dye- sensitized SnO2/TiO2 core/shell photoanodes, measured on longer timescales, is optimized in mixed solvents. The ultrafast transient conductivity data illustrate the crucial role of the electrolyte in regulating the driving forces for electron injection and charge separation at dye-sensitized semiconductor interfaces.
Quantifying the Seasonal Variation of Environmental Pharmaceutical Residues
Authors: Nurmi Tuomas , Kiljunen Toni
Published: April 2024

Pharmaceutical substances, among other contaminants drained from wastewater treatment process and entered into aqueous environments, exhibit significant seasonal dependencies in their environmental concentrations. Although measurement data on removal of pharmaceutical residues in wastewater treatment plants and their degradation in the environment thereafter are readily available, the complexity and uniqueness of the sampling scenarios makes general numerical estimation of these phenomena difficult. To gain quantitative insight on the mass balances of environmental pharmaceutical residues and their seasonal variations, measurement data of four pharmaceuticals were collected from the literature and an effort was undertaken to uniform them and parametrise them with as few variables as feasible. Temperature was found to be a commonly available parameter with a marked trendsetting effect, and the prospect of using it to characterise the variation was examined. Ways to reliably assess the effects of dilution and other advective phenomena on the measured concentrations were explored, and a simple method for using cross-comparisons of different pharmaceuticals to this end is presented. A corresponding fugacity model scenario was also constructed to provide a computational baseline for the mass balance.
Thermally integrated photoelectrochemical devices with perovskite/silicon tandem solar cells: a modular approach for scalable direct water splitting
Authors: Maragno Angela , Morozan Adina , Fize Jennifer , Artero Vincent , Charton Sophie , Matheron Muriel
Published: April 2024

Direct solar water splitting appears as a promising route to produce hydrogen avoiding competition for electricity against other important economic uses. Halogenated hybrid perovskites recently enabled the demonstration of efficient and potentially low-cost photoelectrochemical cells and PV-coupled electrolysers, reaching high efficiencies but so far limited to small active area of a few mm2 so far, in the case of perovskite/silicon tandem solar cells. Here, we show the added value of integrating a thermal exchanger into the system thanks to additive manufacturing, providing a thermally integrated photoelectrochemical cell (IPEC) with performance doubled against the device without any heat exchanger (from 3.3 to 8 % STH). In addition, we develop a modular approach to up-scale this concept from 7.6 to 342 cm², highlighting statistical variations in efficiency of single integrated photoelectrochemical cells and their origin. We conduct an outdoor stability test for 72 hours, with a STH performance of 6.3 %, and investigate the causes of device degradation through the easy disassembly of the integrated photoelectrochemical devices. We identify the interface between perovskite layer and p-layer as critical for reaching stable photoelectrochemical devices integrating perovskite/silicon tandem solar cells.
Lineage-specific changes in mitochondrial properties during neural stem cell differentiation
Authors: Soares Rita , Lourenço Diogo M , Mota Isa F , Sebastião Ana M , Xapelli Sara , Morais Vanessa A
Published: April 2024

Neural stem cells (NSCs) reside in discrete regions of the adult mammalian brain where they can differentiate into neurons, astrocytes, and oligodendrocytes. Several studies suggest that mitochondria have a major role in regulating NSC fate. Here, we evaluated mitochondrial properties throughout NSC differentiation and in lineage-specific cells. For this, we used the neurosphere assay model to isolate, expand, and differentiate mouse subventricular zone postnatal NSCs. We found that the levels of proteins involved in mitochondrial fusion (Mitofusin [Mfn] 1 and Mfn 2) increased, whereas proteins involved in fission (dynamin-related protein 1 [DRP1]) decreased along differentiation. Importantly, changes in mitochondrial dynamics correlated with distinct patterns of mitochondrial morphology in each lineage. Particularly, we found that the number of branched and unbranched mitochondria increased during astroglial and neuronal differentiation, whereas the area occupied by mitochondrial structures significantly reduced with oligodendrocyte maturation. In addition, comparing the three lineages, neurons revealed to be the most energetically flexible, whereas astrocytes presented the highest ATP content. Our work identified putative mitochondrial targets to enhance lineage-directed differentiation of mouse subventricular zone–derived NSCs.
iMPAQT reveals that adequate mitohormesis from TFAM overexpression leads to life extension in mice
Authors: Igami Ko , Kittaka Hiroki , Yagi Mikako , Gotoh Kazuhito , Matsushima Yuichi , Ide Tomomi , Ikeda Masataka , Ueda Saori , Nitta Shin-Ichiro , Hayakawa Manami , Nakayama Keiichi I. , Matsumoto Masaki , Kang Dongchon , Uchiumi Takeshi
Published: April 2024

Mitochondrial transcription factor A, TFAM, is essential for mitochondrial function. We examined the effects of overexpressing theTFAMgene in mice. Two types of transgenic mice were created:TFAMheterozygous (TFAMTg) and homozygous (TFAMTg/Tg) mice.TFAMTg/Tg mice were smaller and leaner notably with longer lifespans. In skeletal muscle, TFAM overexpression changed gene and protein expression in mitochondrial respiratory chain complexes, with down-regulation in complexes 1, 3, and 4 and up-regulation in complexes 2 and 5. The iMPAQT analysis combined with metabolomics was able to clearly separate the metabolomic features of the three types of mice, with increased degradation of fatty acids and branched-chain amino acids and decreased glycolysis in homozygotes. Consistent with these observations, comprehensive gene expression analysis revealed signs of mitochondrial stress, with elevation of genes associated with the integrated and mitochondrial stress responses, including Atf4, Fgf21, and Gdf15. These found that mitohormesis develops and metabolic shifts in skeletal muscle occur as an adaptive strategy.
From Use Value to Context Value:Rethinking News Value in the Digital Age
Authors: 虞 鑫 , 苗 培壮 , 张 铭雨
Published: April 2024

本研究从历史考察和哲学思辨出发,指明使用价值是新闻价值在特定历史时期､特定物质生产条件中的表现,其透射出的本质是新闻在社会关系和实践活动中的语境价值｡互联网等信息技术构建了崭新的新闻传播生态,原有的片面强调时效性､显著性等使用价值的理念不当然适应数字生态,新闻的何种价值能够在新传播环境下引领行业实践､凝结社会共识成为关键问题｡本研究对马克思“劳动二重性”进行理论考察,进而提出新闻的语境价值这一概念予以回应:语境囊括了整体的政治､经济､文化性质和个体的身份､地位､背景等要素;语境价值既体现出新闻抽象自一定的社会历史环境,也显示出新闻对其所处的环境具有反作用｡相较使用价值,新闻的语境价值在哲学意义上更具合理性｡其在理论层面连接重要社会主体与社会议题,具有广阔的研究空间,在实践层面能够回应新闻价值理论的现实困境｡
Community Truth: A Semiotic Ethic Reflection about News Value in the Post-Truth Era
Authors: 冯 月季
Published: April 2024

新闻价值概念的有效性一直以来都被动地受制于媒介环境、市场需求和受众趣味的变化,新闻价值内涵的流动性不仅引发了新闻学自身的学科焦虑与合法性危机,甚至还触及到整个人类理性主义和公共正义的危机。这种危机在后真相时代“情感”取代“事实”的逻辑下被无限放大。这是因为传统意义上的新闻价值标准选择基于经验观察的偶发事件,这种价值标准在后真相时代加速了主体意识的破碎和瓦解,为了对抗这种危机,新闻价值的研究必须实现从“社会事件”向“符号文本”的转向,让新闻文本进入“阐释社群”的公共话语空间,在意义的生成过程中探寻获得身份认同和共享价值观的“社群真知”。“社群真知”是在新闻文本的意义阐释中逐渐显现出来的,具有“真知品格”的新闻文本建构内在地受到公共叙述伦理的规约。
Improvement of forensic medical diagnosis of projectile type injuries from automatic firearm chambered in 5.45 mm caliber through spatial 3D modeling
Authors: Zmiyevska Y.G. , Tryubner K. , Savka I.G.
Published: April 2024

Spatial 3D modeling has become one of the modern and most accurate evidential methods of research, carving out its niche in various fields of medical science and practice. Therefore, our focus has been on laying the groundwork for its implementation in the process of conducting forensic medical examinations of gunshot injuries, which have garnered significant attention from all forensic physicians, particularly after unprovoked aggression from Russia and the onset of active hostilities in our country. The aim of the study was to improve the forensic medical diagnosis of projectile type in injuries from automatic firearm AKS-74U chambered in 5.45x39 mm caliber by utilizing spatial 3D modeling of specific elements within the wound channel. The entire series of experimental shots was conducted using an AKS-74U firearm, with a bullet caliber of 5.45x39 mm. As the research material, Roma Plastilina Number 1 ballistic clay, manufactured in the USA, was used for conducting standardized ballistic tests according to NIJ (National Institute of Justice) and HOSDB (Home Office Scientific Development Branch) standards. The series of experiments consisted of 15 gunshots; then the physical characteristics of the bullet, main morphological elements of the wound of skin and different portions of wound channel were investigated (195 measurements in general). The morphological features of individual elements within the wound channel were measured using conventional measurement tools, and also after their 3D modeling using graphic editors such as "Agisoft Photoscan" and "3ds max." Direct and strong correlations (ranging from 0.60 to 0.72) have been established between the initial velocity, kinetic energy, specific energy of bullet, and the diameter of the entry wound in 3D modeling, as well as the diameters of the wound channel in its central portion, measured both by conventional measuring tools and based on the results of their 3D modeling (р=0,02). Furthermore, inverse correlation relationships of moderate strength (ranging from -0.63 to -0.66) have been detected between the initial velocity, kinetic energy, specific energy, and the presence of abrasion collar around the entry wound (р=0,03). The created conditions allow to conduct the differentiation in diagnosing the type of projectile, the identification and study of new characteristics of key elements in firearm-related injuries, and improvement in measurement accuracy. They also enhance clarity and objectivity during the execution of forensic medical examinations in cases of combat-related firearm injuries.
SAUDI WOMEN EMPOWERMENT IN LEADERSHIP POSITIONS IN HEALTH CARE SECTOR: BARRIERS TO THEIR SUCCESS
Authors: Jrasat Sami Senyal , Zubaidi Faraj Radwan Faraj
Published: April 2024

Purpose: Women’s leadership is a necessary step in the development of civilization. However, the purpose of this study is to identify the barriers and challenges facing Saudi Arabian women seeking leadership positions in the health care industry.
 
Theoretical Framework: The model's constructs are based on the studies cited, and they include barriers related to culture, a woman's personality, organizational politics, women's empowerment, and male top management discrimination.
 
Design/Methodology/Approach: The study used a survey to collect data from 459 female was chosen for the study and a sample comprised of female employees in the Saudi privet healthcare sector from all the regions in the Kingdom of Saudi Arabia.. Using smart PLS, was employed to analyses the research data.
 
Findings: The findings and the results of the analysis indicates that the dimensions of the model included Male top management discrimination, Culture, woman’s personalities, and organizational politics exert different influences on women's empowerment. we find Measuring the effect of moderating factors (The Male top management discrimination) indicates has the strongest effect on Culture and women's empowerment in the Saudi healthcare sector.
 
Research, Practical & Social Implications: As a result, this study has deepened our understanding of the dynamic nature of women's empowerment and the challenges facing women's prospects for leadership while also helping to reframe gender roles. According to this study, women should receive leadership training in order to improve their capacity for decision-making, fulfill their organizational obligations, and expand the opportunities for women's empowerment.
 
Originality/Value: The degree to which Saudi citizens are willing to change their opinions of women's leadership and personalities; to end practices that support male dominance and oppression of women; to end discriminatory laws and policies that impede women's career advancement; and to place their faith in a woman's self-assurance and ability to make the right decisions and shoulder the responsibility in healing.
DIGITAL FINANCE, HUMAN CAPITAL, AND URBAN INNOVATION IN INDONESIA
Authors: Respati Harianto , Triatmanto Boge , Wahyuni Nanik
Published: April 2024

Objective: The objective of this study is to investigate digital finance and urban innovation in 98 cities in Indonesia. This study uses panel data with a time period from 2000 to 2021.  
 
Theoretical Framework: This research is based on theories that discuss digital finance to understand the development of digital financial technology, and human capital theory to explain actors who utilize digital technology and also innovation theory to explain the innovation of actors in digital technology, especially those who live in urban areas with a high level of digital dependence
 
Method: This study uses heterogeneity analysis with a panel data structure. This study also use two-step system generalized method of moments estimation model.
 
Results and Discussion: This research finds that digital finance has a significant impact on urban innovation. However, the heterogeneous impact of digital finance on urban innovation for each city in Indonesia has a different level of commercial attractiveness.
 
Research Implications: In Indonesia, traditional finance also plays an important role in urban innovation where the supply of traditional finance plays a role in moderating the effect of digital finance promotion on urban innovation. Human capital is a vital factor driving innovation.
 
Originality/Value: This research builds on previous research regarding the impact of digital finance on innovation where most of the research related to digital finance and innovation focuses on enterprise technology innovation, while this research focuses on urban innovation as an originality this study.
Analisis Perancangan dan Pemasangan PLTS Kapasitas 1,1 MWp pada Pabrik Farmasi di Kota Semarang
Authors: NUGRAHA RIZKY ADI , FACTA MOCHAMMAD , SYAKUR ABDUL
Published: April 2024

ABSTRAKBiaya utilitas adalah salah satu komponen terbesar dalam biaya produksi sebuah pabrik farmasi. Dari total biaya utilitas, 63% berasal dari pemakaian energi listrik. Jika energi listrik tersebut dapat diperoleh dari Energi Baru Terbarukan (EBT) hingga 10.65%, maka akan berdampak positif bagi biaya produksi. EBT yang dapat dipakai adalah Pembangkit Listrik Tenaga Surya (PLTS) dengan memanfaatkan atap gedung produksi. Selain penghematan perlu diperhatikan dampak interkoneksi PLTS terhadap arah aliran daya, kestabilan sistem kelistrikan saat gangguan, dan potensi terhadap sambaran petir ke instalasi PLTS. Optimalisasi desain PLTS dengan Helioscope menunjukkan kapasitas PLTS yang dapat dipasang hingga 1,1 MWp. Hasil analisis aliran daya dengan ETAP menunjukkan bahwa daya reaktif yang mengalir balik ke jaringan PLN sangat kecil. Sistem kelistrikan dengan injeksi daya dari PLTS ini dapat stabil setelah mengalami gangguan. Berdasarkan metode sudut perlindungan maka untuk 9 bangunan yang dipasang PLTS tersebut diperlukan proteksi petir level IV.Kata kunci: energi surya, kestabilan sistem tenaga, aliran daya, perlindungan sambaran petir ABSTRACTUtility costs are one of the largest components in the production expenses of a pharmaceutical plant. Among utility costs, 63% of total cost takes from electricity consumption. If this electricity can be supplied from Renewable Energy (RE) up to 10.65%, it will have a positive impact on production costs. The viable RE source is PhotoVoltaic Solar Power (PV) by utilizing the building's production area rooftop. The others impact must be given to the PV system's effects on power flow direction, electrical system stability during disturbances, and susceptibility to lightning strikes on the PV installation. Optimation result of the PV system design using Helioscope indicates a capacity of up to 1,1 MWp. Power flow analysis using ETAP results demonstrate minimal reactive power flowing back to the grid. The electrical system with power injection from the PV system regains stability after disturbance. Based on the angle protection method, a lightning protection level IV is required for the 9 buildings with PV systems.Keywords: Solar energy, power system stability, power flow, lightning strike protection.
Efek Jumlah Ridge terhadap Performansi Antena Horn untuk Aplikasi Tomografi
Authors: OKTAFIANI FOLIN , SULISTYANINGSIH SULISTYANINGSIH , MUNIR ACHMAD
Published: April 2024

ABSTRAKPaper ini membahas pengaruh jumlah profil ridge terhadap performansi antena horn untuk aplikasi tomografi. Penelitian ini mengobservasi dua variasi jumlah ridge, yaitu dua ridge dan empat ridge. Untuk mengevaluasi pengaruh jumlah ridge terhadap kinerja antena horn, maka didesain tiga jenis antena horn yang berbeda: antena horn tanpa ridge (horn konvensional), antena horn dengan penambahan dua ridge (DRHA), dan antena horn dengan penambahan empat ridge (QRHA). Ketiga jenis antena difabrikasi dengan menggunakan teknik CNC milling dengan bahan dasar aluminium. Kinerja antena kemudian dikarakterisasi melalui eksperimen yang bertujuan untuk mengamati pengaruh jumlah ridge terhadap parameter-parameter antena, yaitu koefisien refleksi, gain, dan pola radiasi. Hasil dari karakterisasi eksperimen menunjukkan bahwa QRHA, yaitu antena horn dengan penambahan empat ridge, memberikan kinerja terbaik dalam hal bandwidth, beamwidth, dan gain.Kata kunci: antena horn; frekuensi cut-off; tomografi; double-ridge, quad-ridge. ABSTRACTThis paper discusses the effect of ridge number on the horn antenna performance for tomography application. The study observes two variations in the number of ridges: two ridges and four ridges. To evaluate the impact of the number of ridges on the horn antenna's performance, three different types of horn antennas were designed: horn antenna without ridge (conventional horn antenna); horn antenna with two addition ridges (DRHA); horn antenna with four addition ridges (QRHA). The antennas were fabricated using CNC milling technique with aluminum as the base material. The antenna performance was then characterized through experiments aimed at observing the influence of the number of ridges on antenna parameters in term of reflection coefficient, gain, and radiation pattern. The results of the experimental characterization indicated that QRHA, the horn antenna with the addition of four ridges, exhibited the best performance in terms of bandwidth, beamwidth, and gain.Keywords: horn antenna,cut-off frequency,tomography,double-ridge,quad-ridge.
Low carbon technologies to be challenged in the supply chain of concrete structures
Authors: Kasuga Akio
Published: April 2024

Cement used in structural concrete accounts for 60% of all cement. Thus, the amount of CO2 emission by cement in structural concrete in a year is about 5% of the amount emitted by mankind. LCA of structural concrete should consider not only the materials at the product stage but also the maintenance phase at the use stage after construction. A rough indicator is presented to grasp the CO2 emissions of structural concrete. And low-carbon technologies currently in use is introduced. Then the need for multi-cycle structural concrete with a circular economy is presented. Moreover, it is estimated that CO2 emissions due to disasters in the use stage could be enormous. The carbon neutrality of structural concrete is not a risk but an opportunity for us.
Ethical challenges and greenwashing – challenges for structural engineers
Authors: Armitage John
Published: April 2024

In the face of the climate emergency, but also threats to biodiversity, and with exploitation of limited resources posing serious threats, it is easy to resort to ‘greenwashing’, noting small changes which have been provided when large changes are needed to even meet current commitments. However, many of the standard solutions to net zero, such as use of increased proportions of GGBS in concrete, are themselves constrained by limitations to availability of scarce resources.

This paper gives the author’s personal response to these challenges, considering ways in which structural engineers can avoid just ‘greenwashing’, but instead aim to do good as well as just avoiding harm. Engineers must have excellent professionalism and competence, and strong ethics.
Specimen Design and Advanced Material Testing for 3D Printing Concretes
Authors: Radl Elisabeth , Pfleger Marc , Karolyi Julian , Vill Markus
Published: April 2024

This paper deals with the design of concrete samples for the material testing of 3D-printable concrete mixtures. Due to the rapid advancements and increasing pilot projects in the field of 3D printing in construction, it is of great importance to develop standards and design principles that allow a comparison of different material compositions in cast and 3D-printed specimen forms. Starting from general theoretical background of concrete 3D printing and over all characteristics of concrete objects which are built up by multiple material layers, typical issues are identified. From theoretical correlations with the properties of the currently common 3D printing processes, an orthotropic material behaviour can be derived.
Proposal for cable replacement method incorporating arch structure in aging cable-stayed bridges
Authors: Miyachi Kazuhiro , Tonegawa Masato , Nagasawa Shota
Published: April 2024

This study introduces an innovative cable replacement method to address corrosion on an aged cable-stayed bridge with an added arch structure. Through cable influence line analysis, strategies were explored to minimize structural impact during replacement in side spans and central span. As a result, it has been confirmed that the allowable stress of the cables at the crane installation position is within acceptable limits for all cases, and even in the most the highest stress is reduced to about 90 percent. Additionally, strengthening replaced cables or using auxiliary cables during outer cable replacement offer potential for a complete cable replacement. The study also examines the process of erecting an arch rib over the sea, providing a solution for mitigating tension in corroded or broken cables. The proposed cable replacement procedure suggests processes for removal and installation, potentially extending the lifespan of deteriorated cable-stayed bridges.
Unified Explanation of Cracks for Long-Span Prestressed Concrete Box Girder Bridge Using Spatial Lattice Grid Model
Authors: Zhang Hao , Dou Wei , Xu Dong , Jia Qinlong
Published: April 2024

Sustained excessive deflection is a widespread problem of long-span prestressed concrete box girder bridges. Meanwhile, various cracks are widely present in such bridges. However, some cracks are not interpretable according to traditional beam element model. In this paper, a refined finite element model called the spatial lattice grid model (SLGM), developed by the authors, which fully considers the three-dimensional effects of the box girder, is used to conduct a comprehensive analysis of the cracking causes of a long-span bridge having detailed inspection data. The analysis includes cracks that cannot be accurately or even cannot be explained by traditional beam element model. For this research, a unified identification and explanation of all structural cracks discovered during bridge inspection is achieved only using one model. The methodology presented in this paper will lay the foundation for subsequent research on the sustained excessive deflection problem.
Evaluation of the behavior of old beam-plate bridges
Authors: De Backer Hans , Outtier Amelie , Farjad Sami Muhammad
Published: April 2024

In this paper, the case study of a railway bridge in Antwerp, Belgium will be performed. This bridge is constructed using precambered steel-concrete girders, also known as preflex beams. This was the standard solution for railway bridges at the time of construction, namely the end of the 1960s. Nowadays, bridges of this kind have been in use for more than fifty years and suffer different types of deterioration. For some bridges, longitudinal cracks have been found along the length of the precambered girders, which is also the case for the bridge considered here. To be able to get a better understanding of the state of the bridge using modern guidelines, a detailed 3D finite element model will be made, based on the original design notes dating from the 1960s. With this model, the compliance of the bridge with current guidelines, namely the Eurocode, will be verified. Furthermore, the results will be compared with reality since a detailed site investigation and inspection of the bridge have been carried out. The extremely deteriorated state of the bridge is discussed in detail.
Development and validation of a train-bridge interaction model
Authors: Deceuninck Sharon , Loccufier Mia , De Waele Wim , Hectors Kris , De Backer Hans
Published: April 2024

In this paper, a train-bridge interaction model is presented to simulate the behaviour of a bridge during the passage of a train. Two modelling methods are compared: the direct integration method (DIM) and the intersystem iteration method (ISIM). First, a simply supported bridge subjected to a moving spring-mass is modelled using both methods and validated with an analytical solution. Subsequently, incorporating damping into the model adds an extra layer of complexity, rendering the search for analytical solutions unfeasible. The validation of the more complex models is accomplished by comparing them to similar simulations documented in the existing literature. The focus lies on finding an efficient model that could be used by engineers to assess the structural condition of railway bridges. The dynamic interaction model gives a more accurate prediction of the behaviour of the bridge under the passage of the train than including the dynamic amplification factor (DAF) in the static calculation.
Towards Cyber-Secure and Hazard-Resilient Smart Civil Structures
Authors: Cid Montoya Miguel , Rubio-Medrano Carlos , Kareem Ahsan
Published: April 2024

The accelerated growth of urban areas in the last decades has led to an unprecedented increase in the construction of wind-sensitive structures, e.g., long-span bridges, tall buildings, wind turbines, and solar trackers. To effectively control undesired wind- and earthquake-induced responses, a plethora of operational technology and cyber-physical systems have been introduced, including supervisory control and data acquisition systems, programmable logic controllers, and remote terminal units. All these systems are potential targets for cyberattacks and have already been attacked in other sectors, including energy, industry, education, and health. This study analyzes this threat to critical infrastructure, quantifies its potential damage, and develops possible countermeasures and cyber-defenses so the structural engineering community can effectively address this emerging challenge.
Nonlinear aerostatic stability of a curved 275-m span suspension footbridge between Spain and Portugal
Authors: Cid Montoya Miguel , Quintela Juan , Hernández Santiago , Jurado José Ángel
Published: April 2024

This study reports the nonlinear aerostatic stability studies carried out for a suspension footbridge with a curved deck spanning 275 meters over the Miño River between Spain and Portugal. The footbridge's aerostatic performance is controlled by its highly aesthetic but complex three-dimensional configuration, the high slenderness of the deck, the construction process, and the aerodynamic characteristics of the triangular 4.5-meter-wide bluff deck cross- section, which demands a detailed aerodynamic study. The analysis is conducted using a nonlinear modal-based method recently developed by the authors. The deck's rotation is driven not only by the aerodynamic moment-induced rotation but also by the drag-induced rotation due to the configuration of the cable supporting system and, very significantly, by the lift- induced rotation due to the deck's curvature.
Transpennine Route Upgrade – Huddersfield Viaduct
Authors: Norbu Sonam , Harrap Aiken , Spencer Will
Published: April 2024

Huddersfield viaduct is a Victorian masonry arch structure with a number of metallic spans. It is a grade II listed structure of varying condition that needs to be strengthened and modified to fulfil the requirements of the Transpennine Route Upgrade. This structure will accommodate additional tracks as well as portions of the amended platforms and electrification infrastructure. Line speeds are to be increased to 100mph on the Fast lines and 75mph on the Slow lines.
Baker Viaduct: On Track to Better - The Design of a New Railway Viaduct for the 21st Century
Authors: Jackson Chris , Rodriguez Salas Francisco
Published: April 2024

The Trans Pennine Route Upgrade is a major, multi-billion-pound programme of railway improvements which will bring better journeys to passengers travelling across the Pennines between Manchester, Huddersfield, Leeds and York. As part of the scheme a new 350m long, four track viaduct is needed near the town of Dewsbury, West Yorkshire.

In addition to the sustainability benefits realised through transformational transport improvements, the design of the viaduct has focussed heavily on efficient and optimised design for both construction and operation and used wide ranging expertise to optimise the solution. Key features include:

 Splitting the structure into modules to eliminate rail expansion joints – minimising maintenance and disruption in service

 Use of composite diaphragms to maximise structure stiffness, reducing foundation demands from rail loads

 Use of a ‘product’ design approach to optimise off-site fabrication and manufacture of the structure

 Precast deck panels optimised for delivery to site by road and to minimise pollution risk during construction

 Enhanced safety in construction from careful detailing of the precast deck

 Automated design processes to allow a high level of design refinement, reducing steel and concrete quantities

 Foundations designed to minimise disturbance to contaminated ground on the site

This paper will outline the design of the structure and the automation used to create the design, covering key challenges, solutions and innovations adopted.
Estimation of Construction Year of Medium to Long Road Bridges in Zambia using Satellite Imagery
Authors: Hamunzala Bennie , Matsumoto Koji
Published: April 2024

Using the age of the road bridges as one of the inputs, deterministic and probabilistic deterioration models are used to determine the deterioration rates and predict the future physical condition of these structures. This study attempts to estimate the year of construction of 27 road bridges in Zambia. The Technique assumes that the normalized difference water index 2 (NDWI_2) at the target bridge point (TBP) shows detectable differences before and after the construction of a road bridge. Landsat 5 Thematic Mapper in conjunction with Landsat 7 Enhanced Thematic Mapper Plus was used in the Google Earth Engine. Sequential t-test analysis of the regime shift method was applied with a cutoff length 𝑙𝑙𝑙𝑙 = 2 to 𝑙𝑙𝑙𝑙 = 12, and significance level 𝛼𝛼𝛼𝛼 = 0,05, to interpret the estimated year of construction from NDWI_2. The results confirm that it is possible to accurately estimate the year of construction of road bridges in Zambia using this method.
Damage characterisation using Sentinel-1 images: Case study of bridges in Ukraine
Authors: Kopiika Nadiia , Ninić Jelena , Mitoulis Stergios-Aristoteles
Published: April 2024

Bridges are vital infrastructure assets, ensuring the economic activity during the adverse times of conflict. Notwithstanding, there is insignificant research regarding their damage characterization with the use of remote approaches for post-conflict recovery. Monitoring and remote sensing is a promising technology for identification of damages caused by war-induced hazards, including artillery fire, explosions and shelling, and hence facilitate accurate and rapid evaluations of capacity and functionality loss, providing valuable information for reliable risk assessments at emergency and normal circumstances. The geospatial analysis, based on Interferometric SAR (InSAR) products of coherence, calculated between SAR images recorded at different dates could serve as a mean to characterize the level of damage, as demonstrated in this research. The main findings of study include the use fully open-access and remote data for assessment of critical infrastructure damages.
Structural assessment of corbels and half-joints in existing bridges
Authors: Vergoossen Rob , van Vugt Evert , de Boer Martijn
Published: April 2024

In new bridges the use of half-joints and corbels is not recommended from a durability viewpoint. However, in existing bridges they are frequently present. The design and detailing rules for concrete have changed over the last decades. A dilatation joint is always present above a half-joint or corbel. During service-life this joint deteriorates and almost always starts to leak and water with de-icing salts penetrate to the structure underneath. This initiates a large risk on corrosion of the reinforcement steel. However, this steel in this construction detail is crucial for the bearing capacity of the structure itself. What many structural engineers don't know is that the actual detailing of the reinforcement within the half-joint or corbel in relation to the position of the loads determines the stress in the reinforcement a7nd thus the capacity. In addition to this engineering effect, standards and insights have also developed over time. On the bases of some examples of existing corbels and half-joints the different ways to calculate such a structure are described in the paper. The well- known strut-and-tie model as well as the shear-cut-method from the Dutch CUR 40 are compared to non-linear finite element models. It is concluded that (as usual) the devil is in the detail.
Load Transfer Mechanism of Single-sided frictional joints with high strength countersunk head bolts
Authors: Konishi Misato , Yamaguchi Takashi , Hayashi Gen , Yoshimi Masayori
Published: April 2024

This study analyzes the load transfer mechanism in single-sided frictional joints, with high-strength countersunk head bolts. Numerical analysis on coupon-type joints explores the bearing force on the counterbore, the friction force ratio to bearing force, and the slip resistance difference between countersunk head bolts and conventional bolts. The findings revealed that high-strength countersunk head bolted single-sided frictional joints employ a bearing force on the counterbore part by a bolt tightening. Since the stress occurs in the thickness direction of the main plate/the splice plate in the case of high-strength countersunk bolts, yielding of the main plate/the splice plate is limited and the reduction of the bolt axial force is not significant. Consequently, a single-sided frictional joint with high-strength countersunk bolts demonstrated higher slip strength.
Influence of CO₂ Emission Pricing on the Degree of Reuse in Building Projects
Authors: Johnsen Lars Magnus , Olsen Sigurd Lundberg , Haakonsen Sverre Magnus
Published: April 2024

By 2030, CO2 emissions must be drastically decreased to meet the goals of the Paris Agreement. As a result, the modern construction sector urgently needs to transition to a circular economy. This paper investigates how pricing of CO2 emissions at different levels impacts the viability of reuse in building projects. A recently developed design tool is used in two case studies to find appropriate reclaimed steel elements for a truss structure at Old Trafford, Manchester. Utilising optimisation algorithms, the design tool automatically proposes substitutions of elements in a designed building with reusable elements. The conducted case studies demonstrate that an increased CO2 emission price encourages a higher utilisation of reusable elements, even considering the substantial driving distance involved in acquiring them. The results indicate that increasing the CO2 emission price in the future will motivate the reuse of old materials in the building projects of tomorrow.
Effect of Topology Optimization Parameters on Additively Manufactured Space Frame Nodes
Authors: Farrugia Luke , Muñoz Abela Jeanette
Published: April 2024

Topology optimization of a double layer grid space frame node was examined, considering load combinations and various optimization parameters including minimum member sizes and mass reduction constraints. Minimum member size constraints up to 15mm improved stiffness by creating slender secondary supports, enhancing the primary load path. Post‐processing techniques involving smoothing and rationalization reduced maximum stresses by 47%. Compared to conventionally designed nodes, the optimized nodes showed remarkable structural performance, with stress levels reduced by up to 88%. Nodes that were optimized to the load combination performed significantly better than nodes optimized to single load cases. The study also explored physical prototyping feasibility.
Bracklinn Falls Footbridge: efficient modular design
Authors: Knight David , Brownlie Keith , Marks James
Published: April 2024

The construction and access constraints of the Bracklinn Falls site drove the development of a new modular system and governed the structural and aesthetic design for the new footbridge. The resulting structure consists of perforated panels, formed from single sheets of weathering steel folded into a z-shape. These panels were bolted to cross frames and assembled to create a half through beam that spans 21.4m. The structure was assembled bay-by-bay and push launched along a set of temporary rails, before being jacked onto the permanent bearings.

By using a folding process, the modular system minimised welding and hence fabrication time and energy use. This paper looks at how the multiple constraints of a particular project enabled the design team to deliver a footbridge with an exemplary embodied carbon rating [1] as well as achieving economic, robustness, durability and aesthetic goals.