bluuebunny/crossref_metadata_2025 huggingface dataset:
Parametric analysis of vibration characteristics of laminated composite plate structures
Authors: Zhai Yanchun , Zhang Xiaoxue , Zhou Yuesong , Wan Zhiyuan
Published: September 2024

In order to conduct the vibration performance of laminated composite structures, the relationship between the vibration frequency and the parameters such as aspect ratio, width-thickness ratio, elastic modulus ratio and lay-up angle of the plate structure under different boundary conditions was investigated and the variation law of its vibration characteristics was obtained. The conclusions are as follows: 1. The vibration frequency tends to be smaller and smaller as the value of length increases. 2. The vibration frequency tends to be larger and larger as the value of thickness increases. 3. The vibration frequency increases with the increase of the value of elastic modulus.4. The symmetrical lay-up structure with the lay-up angle of the middle ply at 45 degrees has the lowest vibration frequency.
Simulation analysis and test of the spinning process of 304 stainless steel cylindrical parts
Authors: Guo Yaming , Huang Tao , Zheng Yuan , Xu Hengqiu , Huang Mingzhi , Chen Hongwei , Xia Nan , Chen Kai
Published: September 2024

Taking the difference in wall thickness as the evaluation index, the simulation analysis of the spinning process of 304 stainless steel cylindrical parts is carried out. The influence of the roller nose radius, feed speed, and percent thickness reduction on the stress and strain of the roller is studied, and the optimum combination of process parameters is obtained. Through the spinning test, the stainless steel cylindrical parts with an outside diameter of 300.8 mm are successfully spun. After spinning forming and solution treatment, the tensile strength of stainless steel reaches 557~566 MPa, the yield strength reaches 220~232 MPa, and the elongation reaches 41.3%~42.5%.
Electronic and transport properties of 2D α-AsP/α-AsP van der Waals homojunction: A first principle study
Authors: Hong Wei , Zeng Xiandong , Mao Yuliang
Published: September 2024

Following the successful experimental synthesis of α-AsP materials, we design a 2D α-AsP/α-AsP homojunction and use first-principles calculation to study the structural stability, optoelectronic properties, and transport characteristics. The AB-stacked α-AsP/α-AsP is found stable, exhibiting a direct band gap of 1.038 eV. Under a 6% biaxial compressive strain, the electronic properties of α-AsP/α-AsP are transited from semiconductor to metallic. The introduction of an external electric field resulted in a reduced band gap and the emergence of metallic characteristics. Compared with that in monolayer structure, the light absorption in bilayer α-AsP is enhanced. Transport simulations based on a two-probe model reveal promising electron transport properties in the 2D α-AsP/α-AsP homojunction. These findings suggest that 2D α-AsP/α-AsP homojunction has potential application in nanoscale optoelectronic devices.
Thermo-responsible PNIPAM-grafted polystyrene microspheres for mesenchymal stem cells culture and detachment
Authors: Zhao Yuanyuan , Cao Zida , Zhang Jingwei , Tian Jia , Cai Haibo
Published: September 2024

The preparation of cells is a critical step in cell therapy. To ensure the effectiveness of cells used for clinical treatments, it is essential to harvest adherent cells from the culture media in a way that preserves their high viability and full functionality. In this study, we developed temperature-responsive poly(N-isopropylacrylamide) (PNIPAM)-grafted polystyrene (PS) microspheres using reversible addition-fragmentation chain transfer polymerization. These microspheres allow for the non-destructive harvesting of cultured cells through temperature changes. The composition and physicochemical properties of the PNIPAM-grafted PS microspheres were confirmed using infrared spectroscopy, elemental analysis, dynamic light scattering, and thermogravimetric analysis. In vitro experiments demonstrated that these microspheres exhibit excellent biocompatibility, supporting the adhesion and proliferation of various cells. Moreover, the microspheres showed good temperature responsiveness in thermosensitive detachment experiments with GFP-HepG2 cells and umbilical cord mesenchymal stem cells (UC-MSCs). Additionally, through orthogonal experiments, we identified a cell detachment aid mixture that significantly improved the dispersibility of cells detached from the microspheres, enhancing the efficiency of thermosensitive cell detachment by approximately 40%. The harvested UC-MSCs retained their capacity for re-proliferation and trilineage differentiation. Consequently, the temperature-responsive microspheres developed in this study, combined with the cell detachment aid mixtures, hold great potential for large-scale culture and harvesting of therapeutic cells in clinical applications.
MPS blockade with liposomes controls pharmacokinetics of nanoparticles in a size-dependent manner
Authors: Belyaev Iaroslav B , Mirkasymov Aziz B , Rodionov Vladislav I , Babkova Julia S , Nikitin Petr I , Deyev Sergey M , Zelepukin Ivan V
Published: September 2024

Pharmacokinetics of nanomedicines can be improved by a temporal blockade of mononuclear phagocyte system (MPS) through the interaction with other biocompatible nanoparticles. Liposomes are excellent candidates as blocking agents, but the efficiency of the MPS blockade can greatly depend on the liposome properties. Here, we investigated the dependence of the efficiency of the induced MPS blockade in vitro and in vivo on the size of blocking liposomes in the 100–500 nm range. Saturation of RAW 264.7 macrophage uptake was observed for phosphatidylcholine/cholesterol liposomes larger than 200 nm in vitro. In mice, liposomes of all sizes exhibited a blocking effect on liver macrophages, prolonging the circulation of subsequently administrated magnetic nanoparticles in the bloodstream, reducing their liver uptake, and increasing accumulation in the spleen and lungs. Importantly, these effects became more pronounced with the increase of liposome size. Optimization of the size of the blocking liposomes holds the potential to enhance drug delivery and improve cancer therapy.
TiO2 nanotube enhance osteogenesis through Kindlin-2/Integrin β1/YAP pathway-mediated mechanotransduction
Authors: Deng Qing , Yao Quanzhou , Wu Anhang , Li Jinsheng , Li Yingying , Tang Lingling , Zeng Huanghe , Chen Song , Guo Tailin
Published: September 2024

Titanium has been widely employed in the fields of orthopaedics and dentistry, attributed to its superior mechanical and biological properties. The mechanical stimulation induced by the titanium dioxide (TiO2) nanotubes (TNTs) morphology resulting from surface modification has been demonstrated to enhance the osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). Kindlin-2, a pivotal focal adhesion (FA) protein, is involved in mechanical signaling processes through the regulation of stress fibril filament assembly. Additional research is needed to clarify the involvement of Kindlin-2 in the mechanism of TNTs-induced osteogenic differentiation. This study systematically investigated the impact of Kindlin-2 on TNTs-induced osteogenesis and mechanotransduction. TiO2 nanotubes with diameters of approximately 30 nm (TNT-30) and 100 nm (TNT-100) were fabricated and characterized using anodic oxidation. The results showed that TNT-100 significantly increased the expression of Kindlin-2 and enhanced osteogenic differentiation compared to polished titanium and TNT-30. Additionally, Kindlin-2 promotes cytoskeleton assembly by regulating the integrin β1/FAK/RhoA signaling pathway, impacting osteogenic gene expression and BMSC differentiation in a Yes-associated protein-dependent manner. Therefore, these findings contribute to a more comprehensive understanding of the fate of BMSCs on TNTs morphologies and provide a novel theoretical foundation for the development of advanced bone repair biomaterials.
Non-animal derived recombinant collagen-based biomaterials as a promising strategy towards adipose tissue engineering
Authors: Van Damme Lana , Blondeel Phillip , Van Vlierberghe Sandra
Published: September 2024

Adipose tissue engineering (ATE) has been gaining increasing interest over the past decades, offering promise for new and innovative breast reconstructive strategies. Animal-derived gelatin-methacryloyl (Gel-MA) has already been applied in a plethora of TE strategies. However, due to clinical concerns, related to the potential occurrence of immunoglobulin E-mediated immune responses and pathogen transmission, a shift towards defined, reproducible recombinant proteins has occurred. In the present study, a recombinant protein based on human collagen type I, enriched with arginine-glycine-aspartic acid was functionalized with photo-crosslinkable methacryloyl moieties (RCPhC1-MA), processed into 3D scaffolds and compared with frequently applied Gel-MA from animal origin using an indirect printing method applying poly-lactic acid as sacrificial mould. For both materials, similar gel fractions (>65%) and biodegradation times were obtained. In addition, a significantly lower mass swelling ratio (17.6 ± 1.5 versus 24.3 ± 1.4) and mechanical strength (Young’s modulus: 1.1 ± 0.2 kPa versus 1.9 ± 0.3 kPa) were observed for RCPhC1-MA compared to Gel-MA scaffolds. In vitro seeding assays showed similar cell viabilities (>80%) and a higher initial cell attachment for the RCPhC1-MA scaffolds. Moreover, the seeded adipose-derived stem cells could be differentiated into the adipogenic lineage for both Gel-MA and RCPhC1-MA scaffolds, showing a trend towards superior differentiation for the RCPhC1-MA scaffolds based on the triglyceride and Bodipy assay. RCPhC1-MA scaffolds could result in a transition towards the exploitation of non-animal-derived biomaterials for ATE, omitting any regulatory concerns related to the use of animal derived products.
Infinite temperature spin dc conductivity of the spin-1/2 XXZ chain
Authors: Ae Shinya
Published: September 2024

Using the Bethe ansatz method and the thermodynamic Bethe ansatz equations for the higher-spin integrable XXZ chain, the regular zero frequency contribution to the spin current correlation (spin dc conductivity) is analyzed for the spin-1/2 XXZ chain with the anisotropy

0
⩽
Δ
<
1

. In the high temperature limit, we write down the dressed scattering kernels by one quasi-particle bare energies and exactly evaluate the spin dc conductivity at zero magnetic field, which is proportional to the inverse temperature β at the β → 0 limit. We find that the high temperature proportionality constant

σ
0

reg

of the spin dc conductivity is discontinuous at all rational numbers of the anisotropy parameter

p
0

=
π

/

cos

−
1

⁡
Δ
⩾
2

with the gap increasing larger than the second power of growing magnetization on one quasi-particle. The isotropic

Δ
=
1

point is exceptional. Close to this point,

σ
0

reg

slowly increases in proportion to the first power of the one quasi-particle magnetization. On the other hand,

σ
0

reg

is proportional to the second power of the same when p
0 approaches irrational numbers.
Shifting Toward Clean Energy Technology: Assessing Vietnam Critical Minerals Demand and Domestic Resources
Authors: Quoc Huy Phung , Sweetnam Glen E. , Thi Hien Tran
Published: September 2024

Vietnam is progressing toward an energy transition to achieve the 2050 net-zero emissions target by switching from fossil fuel-based to clean energy technologies. According to Politburo’s Resolution No. 55, the renewable energy share in the total primary energy supply will account for 30% by 2045. The newly approved National Power Development Plan set the target to increase the renewables share to 63% of total installed capacity by 2050. The demand for clean energy equipment, such as solar photovoltaic modules, wind turbines, and batteries, is expected to grow rapidly as a result of the decarbonization pathways for the power and transportation sectors in the coming decades. The manufacturing of clean energy equipment will require substantial amounts of critical minerals. Therefore, this study evaluates the demand for major critical minerals in producing clean energy equipment, including cobalt, copper, lithium, nickel, silicon, and rare earth elements. The critical minerals demand is estimated based on critical mineral intensities and additional capacities of clean energy equipment to be installed in 2021-2030 and 2031-2050 stages under Vietnam’s current policies. The results show that the total critical minerals demand in 2021-2030 and 2031-2050 is estimated to increase approximately three-fold and 15-fold, respectively, compared to the 2021 level. Furthermore, the article reviews Vietnam’s critical mineral resources and the potential contribution to domestic and global supply in the coming years.
Progress on Biomass Coal Co-firing for Indonesia Power Plant
Authors: Pasek Ari D. , Soleh Mochamad , Juangsa Firman B. , Darmanto Prihadi S.
Published: September 2024

PT. PLN Indonesia Power (PLN IP) collaborated with other research institutions has conducted several studies to investigate the possibility of using biomass for co-firing with biomass in coal power plant. This review paper integrates results of the previous study results carried out by the authors. Biomass has some disguise disadvantageous such as low energy density, high alkaline metals, high volatile mater, handling difficulties, which may cause derating in power plant and some problem in the combustion facilities such as slagging, corrosion, abrasion, and agglomeration. The investigation carried out reveals that the use of multi-type biomass could eliminate the derating. The pre-treatment of the biomass such as drying and pelletizing could improve not only the energy density but also diminishing the slagging potential.
Decarbonizing Commercial Vehicles: Life Cycle Assessment of Diesel, Petrol and Electric Trucks
Authors: Indati Mustapa Siti , Ramachandaramurthy Vigna K , Mohammad Norsyahida , Shaikh Faheemullah
Published: September 2024

The electric vehicle (EV) landscape in Malaysia is still trailing behind the more established internal combustion engine industry. However, the promotion of EVs has become an increasing priority for the government, especially after committing to achieving net-zero emissions by 2050 at the earliest, as outlined in the 12th Malaysia Plan. Malaysia has set a target of having 1.5 million EVs by 2040, with a notable portion consisting of commercial EVs like buses and trucks. Developing the EV ecosystem and sustainable trucks in Malaysia faces challenges such as high costs and insufficient supporting infrastructure. This study aims to assess the Well-to-wheel life cycle of CO2 emissions and total cost of ownership (TCO) of diesel trucks (DTs), petrol trucks (PTs), and electric trucks (ETs). The study employs IPCC 2006 guidelines to estimate CO2 emissions and a TCO assessment method. The results indicate that the average CO2 emissions of ET are 38% lower than those of DT, and 33% lower than PT. Furthermore, the TCO of ET is 30% and 15% higher than that of DT and PT, respectively. Despite the higher cost, the study concludes that ETs display superior performance in terms of CO2 emission reduction. These findings contribute significantly to the development of policies and knowledge aimed at promoting sustainable trucks, aligning with the country’s net-zero goals.
Accelerating power grid interconnectivity in Southeast Asia: a private sector perspective
Authors: Chen Jennifer , Apañada Marlon , Gonçalves Tatsatom
Published: September 2024

Integrating the power systems between member states of the Association of Southeast Asian Nations (ASEAN) can facilitate economic growth for the region and enable businesses to cost-effectively procure reliable, clean electricity. As corporations strengthen their clean energy commitments, the grid becomes an important enabler of power sector emissions reductions as well as economic development. This paper offers perspectives from the Asia Clean Energy Coalition (ACEC) on the importance of renewing the Memorandum of Understanding (MOU) on the ASEAN Power Grid, focusing on accelerated implementation to expand multilateral power trade and cross-border grid interconnections. ACEC consists of clean energy buyers, sellers, and financiers that can drive economic growth. It supports strengthening the ASEAN Power Grid MOU to recognise the importance of holistic regional grid planning, prioritising interconnectors that scale up clean energy, harmonising regulatory and technical frameworks, and making data accessible to facilitate multilateral power trade and clean energy tracking.
Thermodynamic Metallurgical Analyses of a Sustainable Copper Production in Philippines
Authors: Evidente Ralph Carlo T. , Esguerra Marc Jazer F. , Agron Danielle Jaye S. , Avena Louise Grace S. , Almendrala Michelle C.
Published: September 2024

This paper provides the thermodynamic metallurgical analyses for the copper production of the Philippine Associated Smelting and Refining (PASAR). Unlike the traditional processes, PASAR limits the amount of waste vaporization through utilizing sustainable mining. This involves the waste from manufacturing the by-products were further treated to reduce the impact of the plant operation to the environment. Additionally, the paper discusses in detail the processes used in the manufacture of the PASAR refinery’s main product – copper cathodes. The pyrometallurgical treatment of the concentrate feed starts with flash a melting process, where matte and slag are separated, followed by converting where the latter is blown with oxygen to remove impurities. The resulting blister copper is further refined via anode furnace and electrolysis, producing 99.99% purity copper. Subsequently, the paper describes the thermodynamic and kinetic factors that influence the respective compositions of the matte and slag in the said pyrometallurgical processes.
Assessing the Vulnerability of Phu Quoc Island’s Natural and Socio-economic Systems to Climate Change
Authors: Tri Dao Manh , Tien Dao Manh
Published: September 2024

Phu Quoc Island, a popular coastal destination in Vietnam, faces increasing vulnerability to climate change, particularly sea level rise. This study delves into the landscape of sea level rise vulnerability across diverse sectors and geographies within Phu Quoc. The study examines various sectors and geographic locales, shedding light on the impacts under the 50 cm sea level rise scenario. Coastal regions, notably Duong Dong and An Thoi, stand as epicenters of vulnerability due to their high population density, extensive infrastructure, and pivotal economic sectors. Duong Dong, envisioned as a tourism hub, exhibits the highest vulnerability to climate change, exacerbated by potential issues in natural forest land planning and urban drainage infrastructure. The Agriculture-Fisheries sector faces substantial challenges, including the loss of arable land and declining catch volumes, underscoring the need for enhanced adaptive capacity. The study provides valuable insights for stakeholders, emphasizing the urgency of adaptive measures to mitigate sea level rise impacts in Phu Quoc.
Numerical Evaluation of the performance of different composite bridge decks.
Authors: Elsawy Ehab , Seleem Mostafa , Esa Moustafa , Osman Ashraf
Published: September 2024

A comparative analysis was conducted to facilitate the selection of composite bridge deck configurations. Composite bridge decks, with their lightweight design, corrosion resistance, prefabrication, reduced construction time, and wide design flexibility, reduce substructure costs and offer durability. Static and buckling analyses were conducted using finite element software to compare their weight, stiffness, composite inverse reverse factor, and buckling resistance. The analyses considered the same boundary conditions, loads, composite layup configuration, and material mechanical properties. Various geometries were selected from different literature to evaluate their performance and identify an appropriate design. This paper presents a numerical investigation into the structural performance of five different composite bridge decks under the same conditions. G. Rectangle emerged as the easiest manufacturing deck, consisting of pultruded rectangle tubes, and the worst deck for deflection and buckling. The G. Triangle has the lowest deflection and the highest strain energy density. The G. Arch distinguished as the lightest bridge deck, also has good performance against buckling and a low strain energy density. Finally, the G. 2Trapezoidal and G. Trapezoidal have better total performance than all other decks as they have the highest inertia.
Smart Materials for Modern Facades: An AI-Powered Selection Process
Authors: Amer N , Nagy G
Published: September 2024

According to the mid-21st century’s technological advancements, artificial intelligence has gained popularity as a transformative tool due to its immense integration in the evolving field of architecture. Evidently, it is being used in the building skin design to enhance the energy efficiency and to reduce the continuously rising energy waste and consumption problem in office buildings. Despite AI’s immense advancements, it lacks sufficient data with regards to the turf of smart skin design in office building for energy optimisation. Hence, this research aims to develop a framework for the optimal integration of artificial intelligence in the selection process of smart materials for energy efficient design for office buildings’ skin. To reach this aim, a mixed-method approach using quantitative and qualitative analysis will be implemented. First, theoretical research utilising archives and case study analysis is conducted to determine the various applications of AI in architecture, the components of a smart office building skin focusing on smart materials, the definition of energy efficiency and its measurement tools and the miscellaneous AI tools that are inaugurated to design an office building skin. As a result, a framework will be created by integrating the optimal AI tools in the selection process of smart materials for energy efficient smart skin design. Second, the applied studies are performed using empirical and experimental analysis to test and support the framework through case study analysis and comparison to test the framework obtained from the literature review aiming to cover the gap identified in the selection process of the materials.
Examining the Realization of Residential Satisfaction in the State’s New Housing Projects, with Reference to Cairo, Egypt
Authors: Gamal Mabrouk Hady , Elfiki Sherif , Fahmy Amgad
Published: September 2024

Egypt is currently witnessing unprecedented development in the sector of low-income housing. Up to this point, little research has been conducted to determine how such projects contribute to genuine residents’ satisfaction. Residential satisfaction refers to the sense of contentment that one experiences when their housing needs are met. Residential satisfaction was intended to reveal not just what the existing living conditions were like but also which aspects the government should focus on improving for future low-income housing schemes. The concept of residency encompasses physical, psychological, and social aspects, making it a multifaceted and intricate idea. This paper will address residential satisfaction in relation to the three domains: housing unit, neighborhood, and social environment, as well as the socio-economic characteristics of the occupants, which have also received relatively little investigation. The objective of this study is to identify the factors that contribute to the residential satisfaction of low-income housing in Al-Asmarat. The study adopts a quantitative analysis of a purpose-designed questionnaire survey that investigates residential satisfaction in one of the state’s new low-income housing projects. Data was collected from 120 respondents living in the Al-Asmarat project to evaluate their residential satisfaction. The results showed that residents expressed high levels of satisfaction with many aspects of their new housing project and dissatisfaction with other aspects, for example: 1-Plumbing 2-Internet connection in Housing unit and 1-Living Costs 2-Job opportunities in Neighborhood. Additionally, residents prioritized the following parameters in housing units: level of quietness, residents’ sense of attachment to the unit, and proximity of services. Regarding the neighborhood, they prioritized: residents’ sense of attachment to the neighborhood; the level of street cleanliness; the presence of a youth center; positive official response to residents’ complaints; and aesthetic standards of the streets. Concerning the social environment, they prioritized: the strength of relations between neighbors and the degree of safety in Al-Asmarat city. In summary, it is suggested that the findings of this study may help developers and policymakers improve future low-income housing projects in Egypt towards the development of a better built environment.
Sustainable Strategies Adaptation in Urban Public Spaces of New Cairo Agglomerations
Authors: Nayer Aida , Awad Abdelhamed Soliman Samar
Published: September 2024

Sustainable strategies for urban space management induce the effects of quality of life in new cities. The main aspects that define sustainability in public spaces include the notion of efficiency for services and facilities provided in various sectors that affect people’s well-being and social behavior. Nevertheless, Egyptian Cities encounter challenges faced by the continuous urban sprawl that induces specific needs such as connectivity and management of public spaces, taking into consideration the importance of human scale and adaptive solutions on the level of Streetscape. The research fills the gap between users’ experience in public spaces and the missed opportunities in the extended urbanized context of urban development in the new Cairo residential districts. The methodology adopted consists firstly of an explicit literature review related to existing models assessing public behavior in urban spaces; secondly, a consistent empirical study for opportunities provided in an actual case study represented in the residual public space, and lastly by demonstrating public responsiveness using a structured interview to describe the way they interact in social and the public realm within the context of “the Park View” project. The research represents an explicit review of the actual streetscape impact on human social behavior. The conclusion incorporates highlights on the importance of defining a specific tool to assess public behavior in relation to provided configurations of existing public spaces to enable enhancement of inclusive experience of public spaces as an emergent reality to the notion of Urban Sprawl, within the context of New Cairo agglomerations.
Phosphate removal from aqueous solutions using reversal mode electrocoagulation with iron and aluminum electrodes: RSM optimization and ANN modeling
Authors: Tuyet Nguyen Thi , Nguyen Vinh Dinh , Nguyet Nguyen Thi , Balasubramani Ravindran , Nghia Nguyen Trong
Published: September 2024

Phosphate pollution significantly contributes to eutrophication and the degradation of aquatic ecosystems. The removal of phosphate from wastewater before discharging into the environment is essential for the sustainability of the ecosystem. This work focuses on using a polarity reversal mode electrocoagulation (PRM-EC) system integrated with iron (Fe) and aluminum (Al) electrodes to remove phosphate from wastewater. The conditions for the removal process were optimized using response surface methodology (RSM). Central composite design (CCD) was used to design the experiment and numerical optimization was utilized to find the optimal conditions. The phosphate removal efficiency could reach 93.12% at a current density of 40 A m−2, time of 30 min, pH of 6.4, and electrode distance of 10.5 mm. The energy consumption was about 0.4 kW m−3. The artificial neural network (ANN) modeling showed that the current density was the most influencing factor, followed by time, pH, and electrode distance. The mechanism underlying the PRM-EC process encompassed electrode dissolution, floc formation, phosphate adsorption, and precipitation. The findings in the work show that PRM-EC is an environmentally friendly and effective solution for phosphate removal.
The compact cookbook of structured modes of light
Authors: Rosales-Guzmán Carmelo , Perez-Garcia Benjamin , Cox Mitchell A
Published: September 2024

This concise tutorial serves as a guide to the generation and characterisation of higher-order optical mode bases, such as HG, LG, OAM, IG, MG, BG, and various vector modes. It succinctly outlines the creation methods and practicalities for these structured light forms using liquid crystal spatial light modulators and digital micro-mirror devices. An overview of measurement and characterisation using modal decomposition, and approaches to measure and characterise vector beams is also given (Stokes polarimetry and vector quality factor). The tutorial concludes with a brief discussion on the effects of varying coherence on these complex light structures, providing essential insights for anyone starting out in the field of photonics.
Study on bearing capacity characteristics of Cement-Flyash-Gravel piles and cement-soil compacted piles in composite foundations
Authors: Cheng Xuansheng , Wang Hao , Gong Lijun , Zhou Yingchao
Published: September 2024

To investigate the mechanical performance of Cement-Flyash-Gravel (CFG) piles and Cement-Soil Compacted (CSC) piles in composite foundations (CF), this study uses numerical simulation methods combined with field tests to examine the bearing capacity characteristics and behavior patterns of CFG and CSC pile composite foundations in the collapsible loess area of the Yinxi high-speed railway. The results indicate that the stress ratio between the CFG piles and the surrounding soil follows a trend of ‘steady-sharp rise-steady transition-sharp drop. Additionally, the side friction resistance of the CFG pile reaches its maximum negative value at 2/3 of the pile length and its maximum positive value at 7/8 of the pile length. These findings provide important insights and practical guidance for the design and construction of composite foundations in collapsible loess regions.
A PNP ion channel deep learning solver with local neural network and finite element input data
Authors: Lee Hwi , Chao Zhen , Cobb Harris , Liu Yingjie , Xie Dexuan
Published: September 2024

This paper presents a deep learning method for solving an improved one-dimensional Poisson–Nernst–Planck ion channel (PNPic) model, called the PNPic deep learning solver. The solver combines a novel local neural network, adapted from the neural network with local converging inputs, with an efficient PNPic finite element solver, developed in this work. In particular, the local neural network is extended to handle the complexities of the PNPic model—a system of nonlinear convection–diffusion and elliptic equations with multiple subdomains connected by interface conditions. The PNPic finite element solver efficiently generates input and reference datasets for fast training the local neural network, as well as input datasets for quickly predicting PNPic solutions with high accuracy for a family of PNPic models. Initial numerical tests, involving perturbations of model parameters and interface locations, demonstrate that the PNPic deep learning solver can generate highly accurate numerical solutions.
The Strong Künneth Theorem for Topological Periodic Cyclic Homology
Authors: Blumberg Andrew , Mandell Michael
Published: September 2024

Topological periodic cyclic homology (i.e.,

T

\mathbb {T}

-Tate fixed points of

T
H
H

THH

) has the structure of a strong symmetric monoidal functor of smooth and proper dg categories over a perfect field of finite characteristic.
Automorphisms of Graph Products of Groups and Acylindrical Hyperbolicity
Authors: Genevois Anthony
Published: September 2024

This article is dedicated to the study of the acylindrical hyperbolicity of automorphism groups of graph products of groups. Our main result is that, if

Γ
\Gamma

is a finite graph which contains at least two vertices and is not a join and if

G

\mathcal {G}

is a collection of finitely generated irreducible groups, then either

Γ

G

\Gamma \mathcal {G}

is infinite dihedral or

A
u
t

(
Γ

G

)

\mathrm {Aut}(\Gamma \mathcal {G})

is acylindrically hyperbolic. This theorem is new even for right-angled Artin groups and right-angled Coxeter groups. Various consequences are deduced from this statement and from the techniques used to prove it. For instance, we show that the automorphism groups of most graph products verify vastness properties such as being SQ-universal; we show that many automorphism groups of graph products do not satisfy Kazhdan’s property (T); we solve the isomorphism problem between graph products in some cases; and we show that a graph product of coarse median groups, as defined by Bowditch, is coarse median itself.
New horizons in prediction modelling using machine learning in older people’s healthcare research
Authors: Stahl Daniel
Published: September 2024

Machine learning (ML) and prediction modelling have become increasingly influential in healthcare, providing critical insights and supporting clinical decisions, particularly in the age of big data. This paper serves as an introductory guide for health researchers and readers interested in prediction modelling and explores how these technologies support clinical decisions, particularly with big data, and covers all aspects of the development, assessment and reporting of a model using ML. The paper starts with the importance of prediction modelling for precision medicine. It outlines different types of prediction and machine learning approaches, including supervised, unsupervised and semi-supervised learning, and provides an overview of popular algorithms for various outcomes and settings. It also introduces key theoretical ML concepts. The importance of data quality, preprocessing and unbiased model performance evaluation is highlighted. Concepts of apparent, internal and external validation will be introduced along with metrics for discrimination and calibration for different types of outcomes. Additionally, the paper addresses model interpretation, fairness and implementation in clinical practice. Finally, the paper provides recommendations for reporting and identifies common pitfalls in prediction modelling and machine learning. The aim of the paper is to help readers understand and critically evaluate research papers that present ML models and to serve as a first guide for developing, assessing and implementing their own.
The risk of geriatric syndromes in older COVID-19 survivors among the nonvaccinated population: a real world retrospective cohort study
Authors: Su Chien-Chou , Yang Yi-Ching , Yu Yu-Huai , Tsai Yu-Hsuan , Yang Deng-Chi
Published: September 2024

Background

We aimed to analyse the differences in the risk of geriatric syndromes between older adults with and without coronavirus disease 2019 (COVID-19).

Methods

We conducted a retrospective cohort study of patients from the US Collaborative Network in the TriNetX between January 1, 2020, and December 31, 2022. We included individuals aged older than 65 years with at least 2 health care visits who underwent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction (PCR) tests during the study period. We excluded those with SARS-CoV-2 vaccination, diagnosis with neoplasm and geriatric syndromes before the index date, and death within 30 days after the index date. The index date was defined as the first date of the PCR test for SARS-CoV-2 during the study period. Hazard ratios (HRs) and 95% confidence intervals (CIs) for eight geriatric syndromes were estimated for propensity score-matched older adults with and without COVID-19. Subgroup analyses of sex and age were also performed.

Results

After propensity score matching, 315 826 patients were included (mean [standard deviation] age, 73.5 [6.4] years; 46.7% males and 51.7% females). The three greatest relative increases in the risk of geriatric syndromes in the COVID-19 cohort were cognitive impairment (HR: 3.13; 95% CI: 2.96–3.31), depressive disorder (HR: 2.72; 95% CI: 2.62–2.82) and pressure injury (HR: 2.52; 95% CI: 2.34–2.71).

Conclusions

The risk of developing geriatric syndromes is much higher in the COVID-19 cohort. It is imperative that clinicians endeavour to prevent or minimise the development of these syndromes in the post-COVID-19 era.
Risk factors for Lyme disease among residents of rural, suburban, and urban areas in the United States: A Case-Control Study
Authors: Gould L Hannah , Fee Rebecca , White John , Webb Noah , Carlyle Maureen , Dick Laura , Tan Ye , Walker Valery , Angulo Frederick J , Moïsi Jennifer C , Stark James H , Pugh Sarah
Published: September 2024

lyme disease (LD) is the most common vector-borne disease in the United States, with 476,000 cases estimated each year. It is unclear how LD risk factors vary by residential setting. We conducted a case-control study on LD risk by rural, urban, and suburban residential settings. Individuals from 15 high-incidence states and the District of Columbia in the Optum Research Database were identified as cases (LD medical claim) or controls (no LD medical claim, matched by county of residence and census block group population density). Participants were surveyed about LD history, outdoor activities, and residential characteristics. The final analytic dataset had 750 LD cases and 965 controls. Residence in a rural setting had increased LD risk (OR 1.41, 95% CI 1.16, 1.72). In multivariable analyses, activities associated with LD were hiking/walking/running or having an occupation in forests, wooded areas, or areas of tall grass (all respondents), and spending time in a yard (rural and urban residents only). Public health interventions can help prevent LD in high-incidence jurisdictions by reinforcing the nearuniversal LD risk for rural residents, and highlighting activities that lead to increased LD risk for those in areas with less ubiquitous tick exposure like in urban and suburban settings.
Development and Validation of an Algorithm to Predict Stillbirth Gestational Age in Medicaid Billing Records
Authors: Thai Thuy N , Smolinski Nicole E , Nduaguba Sabina , Bird Steven , Straub Loreen , Bateman Brian T , Hernandez-Diaz Sonia , Huybrechts Krista F , Rasmussen Sonja A , Winterstein Almut G
Published: September 2024

Introduction

With Medicaid covering half of US pregnancies, Medicaid Analytic eXtract (MAX) provides a valuable data source to enrich understanding about stillbirth etiologies.

Objective

We developed and validated a claims-based algorithm to predict GA at stillbirth.

Method

We linked the stillbirths identified in MAX 1999-2013 to Florida Fetal Death Records (FDRs) to obtain clinical estimates of GA (N=825). We tested several algorithms including using a fixed median GA, median GA at the time of specific prenatal screening tests, and expanded versions considering additional predictors of stillbirth within including linear regression and random forest models. We estimated the proportion of pregnancies with differences of ± 1, 2, 3 and 4 weeks between the predicted and FDR GA and the model mean square error (MSE). We validated the selected algorithms in two external samples.

Results

The best performing algorithm was a random forest model (MSE of 12.67 weeks2) with 84% of GAs within ± 4 weeks. Assigning a fixed GA of 28 weeks resulted in an MSE of 60.21 weeks2 and proportions of GA within ± 4 weeks of 32%. We observed consistent results in the external samples.

Discussion

Our prediction algorithm for stillbirths can facilitate pregnancy research in the Medicaid population.
Effort-reward imbalance at work assessed at midlife and prediabetes prevalence assessed 18 years later in a prospective cohort of white-collar workers
Authors: Riopel Camille , Trudel Xavier , Milot Alain , Laurin Danielle , Gilbert-Ouimet Mahée , Brisson Chantal
Published: September 2024

Objectives

Evidence suggests that workers exposed to psychosocial stressors at work from the effort-reward imbalance (ERI) model are at increased risk for type 2 diabetes mellitus (T2DM). However, evidence about the effect of ERI on prediabetes is scarce. This study aimed to examine the association between effort-reward imbalance at work, glycated hemoglobin level and the prevalence of prediabetes in women and men from a prospective cohort study.

Methods

This study was conducted among 1354 white-collar workers followed for an average of 18 years. Effort-reward imbalance at work was measured in 1999 to 2001 using a validated instrument. Glycated hemoglobin was assessed at follow-up (2015 to 2018). Differences in mean glycated hemoglobin levels were estimated with linear models. Prediabetes prevalence ratios (PRs) were computed using robust Poisson regression models.

Results

In women, those exposed to effort-reward imbalance at work at baseline had a higher prevalence of prediabetes (PR = 1.60, 95% confidence interval: 1.02–2.49) at follow-up following adjustment for sociodemographic, lifestyle-related, clinical, and other occupational risk factors. There was no difference in mean glycated hemoglobin levels.

Conclusion

Among women, effort-reward imbalance at work at midlife was associated with the prevalence of prediabetes, at older age. Preventive workplace interventions aiming to reduce the prevalence of effort-reward imbalance at work may be effective to reduce the prevalence of prediabetes among women.
A cross-sectional study on occupational hygiene in biowaste plants
Authors: Madsen Anne Mette , Rasmussen Pil Uthaug , Delsuz Mohammad Seeiar , Frederiksen Margit W
Published: September 2024

Recycling demands are increasing and new biowaste plants are established. The aim of this study is to obtain knowledge about occupational hygiene in biowaste pretreatment plants. At 6 plants, bioaerosol exposure, hand hygiene, and bioaerosol concentrations in work areas were investigated repeatedly. The total inflammatory potential (TIP) of exposures was measured using the human HL-60 cell line. Exposure to airborne bacteria, bacteria able to grow anaerobic, fungi(37°C), endotoxin, and TIP differed between plants and was lowest in a plant transporting waste in closed pipes compared to plants where waste was delivered on the receiving hall floor. Conversely, high exposures were measured in a plant that also processes compost. All microbial components had an impact on TIP of workers’ exposure with main effects of fungi and endotoxin. Seasonality was found for several exposures and TIP, and they were lowest in the winter. Concentrations of bacteria and fungi on workers’ hands at the end of the workday were 15 times higher for production than for nonproduction workers. In work areas, the concentrations of airborne fungi were highest in the waste-receiving area. Bacteria (3.2 µm) and anaerobic bacteria (4.0 µm) were present as larger airborne particles than fungi (2.8 µm), and bacteria were largest in the waste-receiving area. The microbial community compositions of exposures and work areas differed between plants and work areas. In conclusion, measures to reduce exposure should focus on the waste-receiving area and on the production workers. Differences in exposures and community compositions were found between seasons, work areas, work groups, and plants.
DrugDoctor: enhancing drug recommendation in cold-start scenario via visit-level representation learning and training
Authors: Kuang Yabin , Xie Minzhu
Published: September 2024

Medication recommendation is a crucial application of artificial intelligence in healthcare. Current methodologies mostly depend on patient-level longitudinal representation, which utilizes the entirety of historical electronic health records for making predictions. However, they tend to overlook a few key elements: (1) The need to analyze the impact of past medications on previous conditions. (2) Similarity in patient visits is more common than similarity in the complete medical histories of patients. (3) It is difficult to accurately represent patient-level longitudinal data due to the varying numbers of visits. To our knowledge, current models face difficulties in dealing with initial patient visits (i.e. in cold-start scenarios) which are common in clinical practice. This paper introduces DrugDoctor, an innovative drug recommendation model crafted to emulate the decision-making mechanics of human doctors. Unlike previous methods, DrugDoctor explores the visit-level relationship between prescriptions and diseases while considering the impact of past prescriptions on the patient’s condition to provide more accurate recommendations. We design a plug-and-play block to effectively capture drug substructure-aware disease information and effectiveness-aware medication information, employing cross-attention and multi-head self-attention mechanisms. Furthermore, DrugDoctor adopts a fundamentally new visit-level training strategy, aligning more closely with the practices of doctors. Extensive experiments conducted on the MIMIC-III and MIMIC-IV datasets demonstrate that DrugDoctor outperforms 10 other state-of-the-art methods in terms of Jaccard, F1-score, and PRAUC. Moreover, DrugDoctor exhibits strong robustness in handling patients with varying numbers of visits and effectively tackles “cold-start” issues in medication combination recommendations.
Poppers, the Politics of Exemption and the Characteristics of Poppers Users in the annual English Festival Study, 2014–23
Authors: Measham Fiona , McCormack Mark , Simmons Henry , Wignall Liam
Published: September 2024

This paper explores the relationship between socio-demographic characteristics, self-reported alkyl nitrite (‘poppers’) use and sexual behaviours against a backdrop of UK policy change and ambiguity surrounding legal status. In 2024, the Advisory Council on the Misuse of Drugs recommended a unique, government-initiated, legal exemption from the Psychoactive Substances Act 2016 for poppers, because of its use by gay and bisexual men to reduce the risk of injury during anal sexual intercourse. Data from the annual convenience sample English Festival Study 2014–23 (n = 11,566) were used for Bayesian regression analyses of self-reported poppers use in three-time frames: lifetime, past year and past month use. Gay men were significantly more likely to report poppers use and particularly those reporting past-year participation in anal sex. Providing a critical analysis of recent trends in UK drug policy, the authors highlight how differential discrimination occurs within drug control where targeted exemption meets the politics of protected characteristics in UK law. This paper argues that poppers, therefore, provide a unique example in UK drug policy of how an apparent liberalization of legislative control could bolster the overarching drug prohibition regime while maintaining the appearance of rationality and fairness.