bluuebunny/crossref_metadata_2025 huggingface dataset:
Hopf bifurcation control of a modified continuum traffic flow model
Authors: Ai Wenhuan , Fu Jianli , Li Na , Fang Dongliang , Liu Dawei
Published: February 2024

The stability of the transportation system refers to the structural stability of the system. When the system structure is unstable, local or global bifurcation phenomena will occur, which is one of the main reasons for nonlinear traffic phenomena such as congestion. To truly understand the internal mechanism of the formation of these phenomena, it is necessary to analyze the bifurcation of traffic flow. In this paper, the Hopf bifurcation control of a modified viscous macroscopic traffic flow model is studied by using the linear state feedback method, which changes the characteristics of the bifurcation phenomenon of the dynamic system and obtains the required dynamic behavior of the system. First, we can convert the original traffic model into the nonlinear ordinary differential form suitable for bifurcation analysis, solve the equilibrium point of the system, and carry out phase plane analysis. Then, the linear state feedback term is added and the corresponding controlled system is generated, the existence and type of Hopf bifurcation and the existence of saddle node bifurcation are proved. Numerical simulation results show that the analysis and control of Hopf bifurcation in the traffic model are well realized in this paper.
The Landscape of Gut Microbiota and Its Metabolites: A Key to Understanding the Pathophysiology of Pattern in Chinese Medicine
Authors: Zhang Zhaozhou , Du Liqing , Ji Qiuchen , Liu Hao , Ren Zhenxing , Ji Guang , Bian Zhao-Xiang , Zhao Ling
Published: February 2024

Liver Stagnation and Spleen Deficiency (LSSD) is a Chinese Medicine (CM) pattern commonly observed in gastrointestinal (GI) diseases, yet its biological nature remains unknown. This limits the global use of CM medications for treating GI diseases. Recent studies emphasize the role of gut microbiota and their metabolites in the pathogenesis and treatment of LSSD-associated GI diseases. There is increasing evidence supporting that an altered gut microbiome in LSSD patients or animals contributes to GI and extra-intestinal symptoms and affects the effectiveness of CM therapies. The gut microbiota is considered to be an essential component of the biological basis of LSSD. This study aims to provide an overview of existing research findings and gaps for the pathophysiological study of LSSD from the gut microbiota perspective in order to understand the relationship between the CM pattern and disease progression and to optimize CM-based diagnosis, prevention, and therapy.
AWLC: Adaptive Weighted Loop Closure for SLAM with Multi-Modal Sensor Fusion
Authors: Zhou Guangli , Huang Fei , Liu Wenbing , Zhang Yuxuan , Wei Hanbing , Hou Xiaoqin
Published: February 2024

The present prevailing loop closure detection algorithm is mainly applicable for simultaneous localization and mapping (SLAM). Its effectiveness is contingent upon environmental conditions, which can fluctuate due to variations in lighting or the surrounding scenario. Vision-based algorithms, while adept during daylight hours, may falter in nocturnal settings. Conversely, lidar methods hinge on the sparsity of the given scenario. This paper proposes an algorithm that comprehensively utilizes lidar and image features to assign weighted factors for loop closure detection based on multi-modal sensor fusion. First, we use [Formula: see text]-means clustering to produce a point cloud spatial global bag of words. Second, an improved deep learning method is used to train feature descriptors of images while scan context is also used to detect candidate point cloud features. After that, different feature-weighted factors are assigned for homologous feature descriptors. Finally, the detection result related to the maximum weight factor is designated to the optimal loop closure. The adaptive weighted loop closure (AWLC) algorithm we proposed inherits the advantages of different loop closure detection algorithms and hence it is accurate and robust. The AWLC method is compared with popular loop detection algorithms in different datasets. Experiments show that the AWLC can maintain the effectiveness and robustness of detection even at night or in highly dynamic complex environment.
EFFECT OF SUGARCANE BAGASSE ASH ON AA7075 ALLOY-BASED COMPOSITES PREPARED THROUGH STIR CASTING ROUTE
Authors: AMJATH Z. A. , GANESA MOORTHY R. , MOHANAVEL V. , SEIKH A. H.
Published: February 2024

Al7075 is employed as the matrix material and sugarcane bagasse ash (SBA) is a reinforcing material in this work, which is targeted at creating lightweight metal matrix composites (MMCs) at a reasonable cost. Hybridized improved composite castings have been produced and industrial as per ASTM standards with changing wt.% of 0%, 4%, 8%, 12%, and 16% wt.%, correspondingly, after mechanical testing for the evaluation of their strength. It is tested for hardness, tensile, impact, and flexural strength. Composites with hybrid enhanced metal matrix have greater tensile, hardness, and flexural strengths than single-reinforced MMCs. The composite’s tensile and flexural strengths were boosted by a 12[Formula: see text]wt.% increase in bagasse ash, which resulted in maximum values of 96.42% tensile and 23.58% flexural strength, respectively. As the bagasse weight percentage grew over 12%, these values fell, although Bagasse ash AA7075’s impact and ductility improved slightly.
INVESTIGATION OF THE MACHINING PERFORMANCE OF ALUMINUM–BRONZE ALLOY IN WEDM USING TAGUCHI METHOD
Authors: BILGIN MEHMET BURAK
Published: February 2024

Aluminum–Bronze alloys (Al-10%–Cu-balance) are difficult-to-machine cut alloys. Copper (Cu) metal itself is not suitable for machining. The machining performance of the Aluminum–Bronze alloy sample was investigated by the Wire Electric Discharge Machining (WEDM) method, which is among the non-traditional manufacturing methods used in conductive materials that are difficult to process. The aluminum–bronze sample with a diameter of 20[Formula: see text]mm was cut with 0.18[Formula: see text]mm molybdenum wire electrode. Table feedrate, pulse-on-time and pulse-space were used as experimental parameters. Surface roughness and energy consumption values were measured in WEDM process. According to Taguchi analysis and ANOVA results, it was determined that the pulse-on-time parameter was effective on the surface roughness and the table feedrate parameter was effective on the energy consumption.
AN IN-DEPTH INVESTIGATION ON KERF ANGLE IN PIERCED HOLE ON INCONEL-625 SUPERALLOY USING ABRASIVE WATERJET CUTTING PROCESS
Authors: SANTHANAKUMAR M. , VIJAYAKUMAR R. , ADALARASAN R. , RAJESH M.
Published: February 2024

This work investigates the piercing of microholes in turbine shroud rings (Inconel-625) using the Abrasive Waterjet Cutting process. The concern with the hole piercing is the kerf angle caused by the attenuation of the jet energy and stand-off distance, which seriously impacts the processing precision of abrasive water jet piercing. The effects of piercing parameters like machining time (40, 60 and 80[Formula: see text]s), abrasive mesh size (80 mesh and 120 mesh), stand-off distance (1, 2, 3 and 4[Formula: see text]mm), abrasive jet pressure (100, 125, 150 and 175[Formula: see text]MPa) are studied to reduce the kerf angle. The kerf angle increased linearly with a stand-off distance increase at different machining times. By piercing for 60[Formula: see text]s and 80[Formula: see text]s, the lowest values of kerf angle are obtained (0.03∘ and 0.02∘). The optimum conditions for making a pierced hole with a minimum kerf angle of 0.02∘ were achieved with a machining time- of 60[Formula: see text]s, abrasive mesh size- of 20 mesh, and abrasive jet pressure- of Scanning electron microscope (SEM) images and visual measuring system (VMS) images are used to identify the surface characteristics in kerf zone. The features, including ploughing, particle embedment, lip impression and wear path due to the ductile mode of erosion caused by high energy impact, is also discussed.
Multi-Performance Economical Optimization of Base Isolation System with Tuned Inerter Negative Stiffness Damper Subjected to Non-Stationary Seismic Excitation
Authors: He Wenfu , Zhou Yuxiang , Wang Zhihao , Xu Hao , Ning Xiangliang
Published: February 2024

Base isolation proves to be an effective vibration control strategy for buildings. However, the base-isolation floor (BIF) may undergo substantial displacements. To improve the seismic performance of base-isolation system, this paper proposes a multi-performance economical optimization procedure (MPEOP) for exploring the optimal parameters of base isolation system with tuned inerter negative stiffness damper (BIS-TINSD) subjected to non-stationary seismic excitation. The simplified analysis model for BIS-TINSD is developed, followed by the formulation of the state-space representation. The non-stationary seismic excitation is represented as a stationary Gaussian process with a time-modulating function based on the Clough–Penzien spectrum, and combining the equations of motion with seismic excitation results in the augmented state-space representation of structure-damper-excitation, followed by the formulation of differential Lyapunov equation. The multi-objective performance economical index is proposed, in which the performance optimization objective is defined as a weighted combination of base isolation floor displacement and superstructure acceleration, and the economic optimization objective is set as the support stiffness. The Pareto optimal fronts (POF) are adopted to deal with optimal objectives. The examination of optimal design parameters is extended under real earthquake records. The results demonstrate the effectiveness of the MPEOP, and indicate the advantages of the BIS-TINSD compared with the inerter amplify damper (IAD) and negative stiffness inerter damper (NSID).
Moduli of smoothness, K-functionals and Jackson-type inequalities associated with kernel function approximation in learning theory
Authors: Sheng Bao-Huai , Wang Jian-Li
Published: February 2024

We give investigations on a kernel function approximation problem arising from learning theory and show the convergence rate from the view of classical Fourier analysis. First, we provide the general definition for a modulus of smoothness and a [Formula: see text]-functional, and show that they are equivalent. In particular, we give explicit representation for some moduli of smoothness. Second, we establish some Jackson-type inequalities for the approximation error associated with some non-radial kernels. Also we apply these results to some concrete classical kernel function spaces and give Jackson-type inequalities for some concrete RKHS approximation problems. Finally, we apply these discussions to learning theory and describe the learning rates with the moduli of smoothness. The tools we used are Fourier analysis and the semigroup operator. The results show that the Jackson-type inequalities of approximation by some radial kernel functions on compact set with nonempty interiors cannot be expressed with the classical moduli of smoothness.
Low Bandgap Organic Semiconductors for Photovoltaic Applications
Authors: Afaq Adil , Pathak Dinesh , Aamir Muhammad , Aziz Shahid , Butt Zakia , Akhtar Javeed , Akhtar Tashfeen
Published: February 2024

Photovoltaic is one of the best low-cost alternative energy sources. In this paper, organic semiconductors were explored as light harvesters due to their extraordinary properties, but initially, the scientific community focused on synthesizing the large bandgap organic semiconductors, which were unsuitable for photovoltaic applications. Wide bandgap organic semiconductors can capture light only from the UV–Vis region of the solar spectrum, thus showing solar cells’ power conversion efficiency (PCE) of less than 5%. By reducing the bandgap, organic semiconductors can show good compatibility with the air mass (AM) of 1.5 solar spectrums. So, the attention came toward synthesizing low bandgap semiconductors, which led to the enhancement of PCE from 5% to 17%. This review summarizes the overall development of the last 15 years in the field of organic photovoltaic semiconductors. The significant parameters in organic semiconductors are their bandgap, the position of the highest occupied molecular orbital (HOMO), and the lowest unoccupied molecular orbital (LUMO) that can easily be tuned chemically by molecular designing. One of the issues in organic photovoltaic solar devices is the need for absorbers with a narrow bandgap to maximize power conversion efficiencies to a great extent. Moreover, several factors, such as conjugation length, bond length alteration, intermolecular interaction, donor–acceptor charge transfer, planarity, and physical states, are responsible for tuning the bandgap. This review also classifies low bandgap semiconductors based on the core skeleton with their bandgaps, structures, and power conversion efficiencies.
Proposed theoretical value for TSP constant
Authors: den Boer L. D.
Published: February 2024

The traveling salesman problem (TSP) involves determining the shortest length (optimal tour) for a complete circuit through an arbitrary number of points. In the special case that the points to be visited are randomly distributed in the plane within a unit square, and travel costs correspond to the Euclidean distance between points, it is known that the length of the optimal tour divided by the square root of the number of points ([Formula: see text]) asymptotically approaches a constant ([Formula: see text] as [Formula: see text] becomes large. If individual points are randomly drawn from a uniform distribution, the optimal lengths for a sufficiently large number of TSP instances of the same size ([Formula: see text] comprise a normal distribution whose mean approaches [Formula: see text] as [Formula: see text] increases. Moreover, as [Formula: see text] approaches infinity, this distribution gradually narrows such that its standard deviation asymptotically approaches zero. Although the precise value of [Formula: see text] is unknown, published studies indicate its magnitude is approximately 0.712. In this paper, possibly for the first time, precise formulae are proposed for the parameters of the underlying normal distribution and [Formula: see text], based on intuition, mathematical reasoning, and empirical fits to both published and experimentally derived data.
Fractional restrained domination
Authors: Vijayalakshmi P. , Karuppasamy K. , Thomas Tiji
Published: February 2024

Let G be a graph with a set of V vertices and a set of E edges. A function [Formula: see text] is called a restrained dominating function (RDF) of G if, for every [Formula: see text] [Formula: see text]. A restrained dominating function f of a graph G is called minimal (MRDF) if, for all functions [Formula: see text] such that [Formula: see text] and g(v) [Formula: see text] f(v) for at least one [Formula: see text] g is not a RDF. The fractional restrained domination number [Formula: see text] is defined as follows: [Formula: see text]: f is an MRDF of G[Formula: see text] where [Formula: see text].
On some bounds of first Gourava index for Ψ-sum graphs
Authors: Zhou Hao , Ahmad Maqsood , Siddiqui Muhammad Kamran
Published: February 2024

Graph operations play a significant role in constructing new and valuable graphs and capturing intermolecular forces between atoms and bonds of a molecule. In mathematical chemistry and chemical graph theory, a topological invariant is a numeric value extracted from the molecular graph of a chemical compound using a mathematical formula involving vertex degrees, distance, spectrum, and their combination. An intriguing problem in chemical graph theory is figuring out the lower and the upper bound on pertinent topological indices among a particular family of graphs. The first Gourava index for a graph [Formula: see text] is denoted and defined as [Formula: see text] Recently, Kulli studied and derived formulas of the first Gourava index for four graph operations. We proved with the help of counter-examples that the results provided by Kulli produce inaccurate values when compared with exact values. In this paper, we determined the exact formulas and bounds of the first Gourava index for [Formula: see text]-sum graphs. Besides, we presented diverse examples to support our results.
CLIMATE-SMART CITY: CAN CHINA’S SMART CITY POLICY LEAD TO LOW-CARBON DEVELOPMENT OF CITIES?
Authors: DONG KANGYIN , TAGHIZADEH-HESARY FARHAD , ZHAO CONGYU
Published: February 2024

As an intensive mode of urbanization, a smart city may be conducive to achieving a win–win situation of regulating the urban economy and the environment. Based on a quasi-natural experiment in three batches of smart pilot cities, we use the difference-in-differences (DID) method to examine the impact of the smart city policy on CO2 emissions by adopting city panel data in China during the period 2003–2017. This study also explores the influence mechanism and heterogeneous effects of smart city policy. The empirical results indicate that China’s smart city policy effectively lowered CO2 emissions by approximately 1.83%. This primary finding remains reliable using the propensity score matching (PSM)-DID method for robustness check. Moreover, the smart city policy not only directly inhibits CO2 emissions, but also indirectly influences CO2 emissions through scale, structure, and technology effects. Regarding city heterogeneity, the first-tier cities in the eastern area, which have larger population scale and more resource endowments, tend to have stronger negative impacts on CO2 emissions. Based on these conclusions, we highlight several specific policy measures for reducing CO2 emissions and achieving dual carbon targets in China.
Performance Analysis of Fiber Laser Micro-Marking on Aluminium 7075 Alloy
Authors: Pramanik D. , Sen A. , Biswas S. , Roy N. , Banerjee N. , Biswas R. , Kuar A. S.
Published: February 2024

Analyzing the performance of fiber laser micro-marking on aluminium alloy under focus–defocus conditions entails determining the way varying the focus position during the marking process impacts the overall performance. A special process variable defocus height refers to the distance between the focal point of the laser beam and the surface of the material being marked. In micro-marking, the focal point can be moved above or below the surface to generate distinct effects. The paper determines the optimal parameters for laser micro-marking on aluminium 7075 alloy, including laser power, pulse frequency, scan speed, defocus height (the distance between the top surface and the focal point), and duty cycle, for mark quality and characteristics such as depth and mark width. Experimental results showcase that laser parameters affect mark width and depth nonlinearly. In addition, small variations in laser power, scanning speed, or focus height, have led to moderate changes in dimensions of the mark geometry. A target mark of 40[Formula: see text][Formula: see text]m in width and 25[Formula: see text][Formula: see text]m in depth is achieved by combining optimum settings like a power of 23.862[Formula: see text]w, a duty factor of 45%, a pulse frequency of 76.0506[Formula: see text]Khz, a scanning speed of 0.70[Formula: see text]mm/s, and a defocus height of 0.7[Formula: see text]mm.
Role of Preimplantation Genetic Testing in Indian Women with Advanced Maternal Age to Optimize Reproductive Outcomes
Authors: Mantravadi Krishnachaitanya , Gedela Durga Rao , Rawat Beena , Chauhan Pooja
Published: February 2024

Purpose: Does preimplantation genetic testing for aneuploidy (PGT-A) in embryos help women of advanced maternal age (AMA) of Indian origin to achieve better reproductive outcomes?

Methods: In this retrospective study, a total of 267 patients were recruited, of which 53 patients (PGT-A group) consented to PGT-A, followed by euploid embryo transfer, whereas the remaining 214 patients (non-PGT-A group) underwent frozen embryo transfer (FET) of unscreened morphologically graded blastocysts.

Results: A significant increase in the clinical pregnancy rate was observed in the PGT-A group when compared to the non-PGT-A group (71.6% vs. 51%, [Formula: see text]), while the miscarriage rate was found to be lower in the PGT-A group compared to the non-PGT-A group (11% vs. 25%, [Formula: see text]). The live birth rates were also significantly better in PGT-A group (60.3% vs. 25.6%, [Formula: see text]). In the PGT-A group, similarly, the implantation rate was found to be significantly higher than in the non-PGT-A group (53% vs. 33%, [Formula: see text]).

Conclusions: The data suggest that PGT-A testing in women of AMA can improve their reproductive outcomes. Role of PGT-A seemed equally efficient in women of Indian origin and showed no difference based on ethnicity.
Contemporary Patterns and Progressions in Topologies of DC–DC Converters with Control Methodology
Authors: Gupta Mukur , Gupta Nitin , Sahoo Akash Kumar , Morey Meghraj
Published: February 2024

DC–DC converters have achieved great popularity in recent decades due to their immense penetration in various applications. With this motivation, the authors have conducted a thorough review of recent advancements in various topologies of DC–DC converters. The need for DC power has raised further for certain applications like grid integration of distributed generation (DG), solar photovoltaic (PV), wind power generation (WPG), fuel cells (FC), etc. The investigation of converter topology is performed to achieve the desired objective of a specific application. Like in a PV system, to obtain the inherent capability of a DC–DC converter for operating at the maximum power point (MPP) and thereby electronically extracting the maximum power from the source. Hence, a detailed review of topological advancements on the low to medium-voltage and medium-to-high-power DC–DC converters has been carried out. Moreover, a thorough investigation has been carried out on profuse closed-loop strategies and compared with each other for obtaining the optimum or maximum output performance and thereby obtaining the utmost source utilization. The modern control techniques though have relatively more calculation time but, they tend to reduce the steady-state error that leads to the stabilization of the converter. Lastly, certain applications of the DC–DC converters have been explained to get an overall idea of the usefulness of such power converters.
Investigating the Path Dependent Aging Behavior of Nickel Cobalt Aluminum Oxide Cathode Batteries During High C-rate Cycling Conditions
Authors: Hamar Jacob C. , Stuckenberger Magdalena , Sturm Johannes , Schmitt Julius , Rogge Marcel , Erhard Simon V. , Jossen Andreas
Published: February 2024

Nickel-rich cathode material batteries such as the nickel cobalt aluminum oxide with graphite anode are common in the automotive sector due to their high energy density and power performance capabilities, however, they are limited in lifetime performance. Accelerated degradation in specific operation conditions, such as high C-rates are known to significantly contribute to this issue. To better understand a chronological dependence of these high-stress conditions occurring during battery lifetime, a path dependent aging study is performed using profiles inspired by high-performance race operation. The focus on C-rates >1C during charging and discharging using real-world inspired profiles- known to induce particle cracking or lithium plating- addresses the need to understand aging behavior in less studied, but highly relevant high-performance automotive context. The aging conditions were tailored to induce specific degradation modes to better identify potential degradation mode coupling. Using differential voltage and capacity analysis techniques, degradation modes were identified which likely contributed to path dependent aging behavior, including loss of lithium inventory and loss of active material in the positive electrode. Two critical paths were identified in this study where later high C-rate conditions in the form of fast-charging at temperatures of 25 °C resulted in accelerated aging and where loss of lithium inventory induced stresses in the positive electrode, accelerating loss of active material.
Stabilizing Lithium-Oxygen Batteries through In Situ Generated Phenyl/LiF-Rich Hybrid SEI Layer with Sulfonyl Fluoride Electrolyte Additive
Authors: Wu Min-Sheng , Zhang Xiao-Ping , Li Chu-Yue , Wang Qian-Yan , Rong Yuan-Jia , Liao Ya-Ling , Gao Meng-Lin , Chen Wei-Rong
Published: February 2024

Lithium-oxygen batteries have a wide application due to their ultra-high theoretical energy density. However, uncontrollable lithium dendrites and highly reactive oxygen species greatly cause the corrosion of lithium anodes and the degradation of the electrolytes. In our work, we introduce 4-Methylbenzenesulfonyl Fluoride (4-MBSF) as a highly efficient film-forming additive. It can form a stable inorganic-organic composite solid electrolyte interfacial layer and inhibit the growth of lithium dendrites to stabilize the lithium anode, thus dramatically enhancing the lives of lithium-oxygen batteries. The sulfonyl fluoride group of 4-MBSF can react with LiOH to form a LiF-rich protective layer on the lithium metal surface, which can improve stripping/deposition stability and ionic conductivity. Besides, the π-conjugation of the benzene ring can improve the flexibility of the SEI layer to accommodate volume changes of the lithium anode during cycling and inhibit the attacks of the reactive oxygen species. The cycle life of lithium-oxygen batteries with 4-MBSF is prolonged to 400 cycles.
Relaxation Analysis of Silicon Monoxide-Graphite Composite Anode
Authors: Fu Jiawei , Takai Shigeomi , Yabutsuka Takeshi , Yao Takeshi
Published: February 2024

Relaxation analysis based on X-ray diffraction has been carried out on SiO-graphite composite anode of the lithium-ion battery, focusing on the lithium migration during the relaxation accompanied by the stage change of lithium graphite intercalation compound (Li-GIC). After the termination of electrochemical lithium insertion, XRD peaks of Li-GIC change from stage I into stage II during the relaxation. Due to the slower reaction for lithiation of SiO in comparison with the intercalation of Li-GIC, lithium migration from Li-GIC toward SiO to change the Li-GIC from stages I into II toward the equilibrium lithium distribution. The stage change is more apparent for higher current density at the charging, presumably due to the core–shell model of lithium concentration of SiO after charging.
Bottom-up Gold Filling of Trenches in Curved Wafers
Authors: Josell D. , Raciti D. , Gnaupel-Herold T. , Pereira A. , Tsai V. , Yu Q. , Chen L. , Stauber M. , Rawlik M. , Stampanoni M. , Moffat T. P. , Romano L.
Published: February 2024

A

Bi

3
+

-stimulated Au electrodeposition process in slightly alkaline

Na

3

Au

SO

3

2

+

Na

2

SO

3

electrolytes has been previously demonstrated for void-free extreme bottom-up filling of high aspect ratio trenches in gratings that are key to advanced X-ray imaging technologies. Effective use of the full area of the gratings with conventional X-ray sources requires they have a finite radius of curvature to align the high aspect ratio Au-filled trenches with divergent X-rays. With that in mind, this work demonstrates bottom-up Au filling in gratings that are attached to curved holders. Contactless mapping of the Au-filled gratings captures residual curvature that is retained after their release from the curved holders (i.e., intrinsic curvature). X-ray diffraction captures the elastic strains in the Si underlying the Au-filled trenches of the grating. Complementary measurements on the surfaces of unpatterned Si wafers mounted on curved holders capture the actual curvatures and strains imposed in the mounted gratings. The gratings, either intrinsically curved or re-bent, provide high visibility across the entire field of view of an X-ray phase contrast imaging system with elastic strains substantially below those in planar gratings bent to the same radius.
Conceptualizing Discussions on the Dark Web: An Empirical Topic Modeling Approach
Authors: Basheer Randa , Alkhatib Bassel
Published: February 2024

Social networks on the Internet have become a home that attracts all types of human thinking to exchange knowledge and ideas and share businesses. On the other hand, it has also become a source for researchers to analyze this knowledge and frame it in patterns that define types of thoughts circulating on these networks and representing the communities around them. In particular, some social networks on the Dark Web attract a special kind of thinking centered around the malicious and illegal activities disseminated on websites and marketplaces on the Dark Web. These networks involve discussions to exchange and discourse information, tips, and advice on performing such business. Studying social networks on the Dark Web is still in its infancy. In this paper, we present a methodology for analyzing the content of social networks on the Dark Web using topic modeling methods. We demonstrate the needed stages for the topic modeling process, beginning with data preprocessing and feature extraction to topic modeling algorithms. We utilize and discuss the following four topic models: LDA, CTM, PAM, and PTM. We discuss the following four topic coherence measures as evaluation metrics: UMass, UCI, CNPMI, and CV, demonstrating the selection of the best number of topics for each model according to the most coherent produced topics. Furthermore, we discuss the limitations, challenges, and future work. Our proposed approach highlights the ability to discover the latent thematic patterns in conversations and messages in the common language used in social networks on the Dark Web, constructing topics as groups of terms and their associations. This paper provides researchers with a leading methodology for analyzing thought patterns on the Dark Web.
Chemical Constituents and Antimicrobial and Antioxidant Activities of Essential Oil from Dried Seeds of Xylopia aethiopica
Authors: Ndoye Samba Fama , Tine Yoro , Seck Insa , Ba Lalla Aicha , Ka Seydou , Ciss Ismaila , Ba Abda , Sokhna Seynabou , Ndao Moussa , Gueye Rokhaya Sylla , Gaye Nango , Diop Abdoulaye , Costa Jean , Paolini Julien , Seck Matar
Published: February 2024

The study aimed to investigate the chemical composition and antimicrobial and antioxidant activities of the essential oil from dried seeds of Xylopia aethiopica. The essential oil was obtained by hydrodistillation and analyzed by GC/FID and GC/MS. The essential oil yield was 1.35%. Forty-nine compounds were identified in the essential oil with 1,8-cineole (16.3%), β-pinene (14.8%), trans-pinocarveol (9.1%), myrtenol (8.3%), α-pinene (5.9%), and terpinen-4-ol (5.6%) as major components. The antimicrobial activity of this essential oil was studied using disk diffusion and broth microdilution methods on four bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa) and one fungus (Candida albicans). The essential oil exhibited excellent activity against S. aureus, E. faecalis, and C. albicans and moderate activity against E. coli. Among all strains tested, C. albicans showed the best sensitivity with a MIC of 50 mg/mL. The antioxidant activity was examined using a DPPH-free radical scavenging assay. The essential oil of X. aethiopica showed low antioxidant activity (IC50 = 784.604 ± 0.320 mg/mL) compared to that of ascorbic acid and the reference compound (IC50 = 0.163 ± 0.003 mg/mL). The results indicate that consumption of X. aethiopica seeds can reduce the virulence of food-borne pathogens and their resistance to antibiotics.
Characteristics of Serum Lipid Metabolism among Women Complicated with Hypertensive Disorders in Pregnancy: A Retrospective Cohort Study in Mainland China
Authors: Liu Lidong , Zhang Xiaolei , Qin Kaizhou , Xu Chengjie , Ruan Fangyi , Liu Yadan , Zhao Huanqiang , Wang Yinan , Xiong Yu , Zhou Qiongjie , Li Xiaotian
Published: February 2024

Background. Altered maternal serum lipid metabolism is associated with hypertensive disorders in pregnancy (HDP). However, its range in pregnancy and characteristic among different subgroups of HDPs are unclear. Methods. Pregnant women with HDP who underwent antenatal care and delivered in Obstetrics and Gynecology Hospital of Fudan University during January 2018 to August 2022 were enrolled. The levels of total cholesterol (TC), triglycerides (TG), high‐density lipoprotein cholesterol (HDLC), low‐density lipoprotein cholesterol (LDLC), apolipoprotein (Apo)‐A, B, and E, free fatty acids (FFA), and small and dense low‐density lipoprotein cholesterol (sdLDL) were measured during 4–16 weeks and 28–42 weeks of pregnancy. Results. A total of 2648 pregnant women were diagnosed with HDP, 1,880 of whom were enrolled for final analysis, including 983 (52.3%) preeclampsia (PE), 676 (36.0%) gestational hypertension (GH), and 221 (11.7%) chronic hypertension (CH). For all HDPs, serum TC, TG, LDLC, HDLC, Apo‐A, Apo‐B, Apo‐E, and sdLDL increased significantly during pregnancy, while FFA decreased significantly. Notably, the levels of TC, LDLC, Apo‐B, and sdLDL in PE group were equal to or lower than those in CH group at 4–16 weeks of pregnancy, but increased greatly during pregnancy (P < 0.05). Conclusions. Maternal serum lipid levels changed through pregnancy among women with HDPs. Women complicated with PE seem to have undergone a more significant serum lipid change compared to those with GH or CH.
Lower Dose of 5 mL of 1% Lidocaine is More Suitable than the Conventional 10 mL for Caudal Block in Transrectal Prostate Biopsy: A Retrospective Cohort Study
Authors: Ueda Norichika , Sato Mototaka , Mori Shunsuke , Matsukawa Atsuki , Oki Yuta , Kujime Yuma , Mizuno Ryoya , Horitani Hiromu , Yamamoto Tetsuya , Fukae Shota , Yoshinaga Mitsuhiro , Matsushita Makoto , Akiyama Mai , Kamido Satoshi , Honda Ayako , Nakayama Jiro , Tei Norihide , Miyake Osamu
Published: February 2024

Objectives. In Japan, caudal block with 1% lidocaine is commonly used for transrectal prostate biopsy. Although 10 mL of 1% lidocaine is commonly used, the appropriate dosage of 1% lidocaine has not been studied. Our hospital routinely uses two different doses (5 or 10 mL) of 1% lidocaine for caudal block for transrectal prostate biopsy. Herein, we retrospectively evaluated the efficacy and safety of both doses of 1% lidocaine. Methods. This retrospective study included 869 patients who underwent transrectal prostate biopsy with caudal block at our hospital. The amount of 1% lidocaine was determined by the day of the week on which the biopsy was performed, and the patient voluntarily chose the day of the biopsy, unaware of the dose of 1% lidocaine used on that day. Pain, anal sphincter tonus, cancer diagnosis rate, and early complications were compared. Results. In total, 466 and 403 patients received 5 and 10 mL of 1% lidocaine for a caudal block, respectively. After propensity-score matching for patient characteristics, each group contained 395 patients. The pain score, anal sphincter tonus score, or prostate cancer diagnosis rate were not significantly different between the two groups. However, rectal bleeding was significantly more frequent and severe in the 10-mL than the 5-mL group (p=0.018 and p=0.0036, respectively). The incidence of other complications was not significantly different between the groups. Conclusions. Our results suggest that 5 mL of 1% lidocaine may be more suitable than 10 mL for caudal block during transrectal prostate biopsy.
Effects of Different SARS-CoV-2 Testing Strategies in the Emergency Department on Length of Stay and Clinical Outcomes: A Randomised Controlled Trial
Authors: Boldt Kira Louisa , Bolanaki Myrto , Holert Fabian , Fischer-Rosinský Antje , Slagman Anna , Möckel Martin
Published: February 2024

The turn-around-time (TAT) of diagnostic and screening measures such as testing for SARS-CoV-2 can affect a patient’s length of stay (LOS) in the hospital as well as the emergency department (ED). This, in turn, can affect clinical outcomes. Therefore, a reliable and time-efficient SARS-CoV-2 testing strategy is necessary, especially in the ED. In this randomised controlled trial, n = 598 ED patients presenting to one of three university hospital EDs in Berlin, Germany, and needing hospitalisation were randomly assigned to two intervention groups and one control group. Accordingly, different SARS-CoV-2 testing strategies were implemented: rapid antigen and point-of-care (POC) reverse transcription polymerase chain reaction (rtPCR) testing with the Roche cobas® Liat® (LIAT) (group one n = 198), POC rtPCR testing with the LIAT (group two n = 197), and central laboratory rtPCR testing (group three, control group n = 203). The median LOS in the hospital as an inpatient across the groups was 7 days. Patients’ LOS in the ED of more than seven hours did not differ significantly, and furthermore, no significant differences were observed regarding clinical outcomes such as intensive care unit stay or death. The rapid and POC test strategies had a significantly (p<0.01) shorter median TAT (group one 00:48 h, group two 00:21 h) than the regular central laboratory rtPCR test (group three 06:26 h). However, fast SARS-CoV-2 testing strategies did not reduce ED or inpatient LOS significantly in less urgent ED admissions. Testing strategies should be adjusted to the current circumstances including crowding, SARS-CoV-2 incidences, and patient cohort. This trial is registered with DRKS00023117.
Comprehensive Ophthalmological Evaluation in Atopic Dermatitis
Authors: Valeille Anaïs , Ouilhon Coralie , Subtil Fabien , Hacard Florence , Jaulent Coline , Bérard Fréderic , Nicolas Jean-François , Fauquert Jean-Luc , Nosbaum Audrey
Published: February 2024

Introduction: Atopic dermatitis (AD), a chronic type 2 inflammatory skin disease, is frequently associated with ocular surface diseases (OSD) which may appear or worsen under anti-type 2-targeted treatments. However, the exact prevalence of OSD and the ophthalmology referral criteria remain ill-defined in AD patients before initiating such biotherapies. We aimed to characterize the prevalence, the nature and the factors related to OSD development in AD that may justify an ophthalmological management. Methods: A total of 98 consecutive AD inpatients without biological treatment were retrospectively included. These were systematically evaluated by an ophthalmologist during their dermatological care. Clinical and laboratory data were analysed to characterize OSD and their risk factors. Results: OSD were found in 83/98 AD patients (85%); mainly dry eye syndrome (64%, 63/98), allergic conjunctivitis (42%, 41/98), posterior (33%, 32/98), and anterior blepharitis (27%, 26/98). In AD patients without ocular symptoms, OSDs were also frequently found (63%, 12/19) and were mostly mild. Risk factors for OSD were history of allergic rhinitis, allergic sensitization, head and neck AD, ocular symptoms (foreign body sensation in the eye, burning, itching, photophobia), and total IgE level >3,000 kU/L. Conclusion: The prevalence of OSD was high, even in asymptomatic patients. The risk factors identified may indicate the need for ophthalmological examination for therapeutic management, especially when biological agents targeting type 2 inflammation are considered.
Eicosanoids and Oxylipin Signature in Hereditary Hemochromatosis Patients Are Similar to Dysmetabolic Iron Overload Syndrome Patients but Are Impacted by Dietary Iron Absorption
Authors: Lobbes Hervé , Dalle Céline , Pereira Bruno , Ruivard Marc , Mazur Andrzej , Gladine Cécile
Published: February 2024

Introduction: Oxylipins are mediators of oxidative stress. To characterize the underlying inflammatory processes and phenotype effect of iron metabolism disorders, we investigated the oxylipin profile in hereditary hemochromatosis (HH) and dysmetabolic iron overload syndrome (DIOS) patients. Methods: An LC-MS/MS-based method was performed to quantify plasma oxylipins in 20 HH and 20 DIOS patients in fasting conditions and 3 h after an iron-rich meal in HH patients. Results: Principal component analysis showed no separation between HH and DIOS, suggesting that the clinical phenotype has no direct impact on oxylipin metabolism. 20-HETE was higher in DIOS and correlated with hypertension (p = 0.03). Different oxylipin signatures were observed in HH before and after the iron-rich meal. Discriminant oxylipins include epoxy fatty acids derived from docosahexaenoic acid and arachidonic acid as well as 13-HODE and 9-HODE. Mediation analysis found no major contribution of dietary iron absorption for 16/22 oxylipins significantly affected by the meal. Discussion: The oxylipin profiles of HH and DIOS seemed similar except for 20-HETE, possibly reflecting different hypertension prevalence between the two groups. Oxylipins were significantly affected by the iron-rich meal, but the specific contribution of iron was not clear. Although iron may contribute to oxidative stress and inflammation in HH and DIOS, this does not seem to directly affect oxylipin metabolism.
Antithrombotic Treatment for Chronic Coronary Syndrome: Evidence and Future Perspectives
Authors: Kulasingam Archana , Pareek Manan , Gragnano Felice , Würtz Morten , Pryds Kasper , Calabrò Paolo , Grove Erik Lerkevang
Published: February 2024

Background: The clinical presentation of coronary artery disease can range from asymptomatic, through stable disease in the form of chronic coronary syndrome, to acute coronary syndrome. Chronic coronary syndrome is a frequent condition, and secondary prevention of ischaemic events is essential. Summary: Antithrombotic therapy is a key component of secondary prevention strategies, and it may vary in type and intensity depending on patient characteristics, comorbidities, and revascularisation modalities. Dual antiplatelet therapy is the default strategy in patients with chronic coronary syndrome and recent coronary stent implantation, while antiplatelet monotherapy is commonly prescribed for long-term prevention of cardiovascular events. Oral anticoagulation, in combination with antiplatelet therapy or alone, is used in patients with, e.g., concomitant atrial fibrillation or venous thromboembolism. Key Messages: This review provides an overview of antithrombotic treatment strategies in patients with chronic coronary syndrome. Key messages from current guidelines are conveyed, and we provide future perspectives on long-term antithrombotic strategies.
Social Determinants of Health Including Child Opportunity Index Leading to Gaps in Care for Patients With Significant Congenital Heart Disease
Authors: Zaidi Abbas H. , Saleeb Susan F. , Gurvitz Michelle , Bucholz Emily , Gauvreau Kimberlee , Jenkins Kathy J. , de Ferranti Sarah D.
Published: February 2024

Background

Gaps in care (GIC) are common for patients with congenital heart disease (CHD) and can lead to worsening clinical status, unplanned hospitalization, and mortality. Understanding of how social determinants of health (SDOH) contribute to GIC in CHD is incomplete. We hypothesize that SDOH, including Child Opportunity Index (COI), are associated with GIC in patients with significant CHD.

Methods and Results

A total of 8554 patients followed at a regional specialty pediatric hospital with moderate to severe CHD seen in cardiology clinic between January 2013 and December 2015 were retrospectively reviewed. SDOH factors including race, ethnicity, language, and COI calculated based on home address and zip code were analyzed. GIC of >3.25 years were identified in 32% (2709) of patients. GIC were associated with ages 14 to 29 years (
P
<0.001), Black race or Hispanic ethnicity (
P
<0.001), living ≥150 miles from the hospital (
P
=0.017), public health insurance (
P
<0.001), a maternal education level of high school or less (
P
<0.001), and a low COI (
P
<0.001). Multivariable analysis showed that GIC were associated with age ≥14 years, Black race or Hispanic ethnicity, documenting <3 caregivers as contacts, mother's education level being high school or less, a very low/low COI, and insurance status (C statistic 0.66).

Conclusions

One‐third of patients followed in a regional referral center with significant CHD experienced a substantial GIC (>3.25 years). Several SDOH, including a low COI, were associated with GIC. Hospitals should adopt formal GIC improvement programs focusing on SDOH to improve continuity of care and ultimately overall outcomes for patients with CHD.
AT1‐AA Is Produced in Offspring in Response to Placental Ischemia and Is Lowered by B‐Cell Depletion Without Compromising Overall Offspring Health
Authors: Campbell Nathan , Deer Evangeline , Solise Dylan , Cornelius Denise C. , Turner Ty , Amaral Lorena M. , Herrock Owen , Jordan Ariel , Shukla Shivani , Ibrahim Tarek , LaMarca Babbette
Published: February 2024

Background

Preeclampsia, new‐onset hypertension during pregnancy alongside other organ dysfunction, is the leading cause of mortality for the mother and low birth weight for the baby. Low birth weight contributes to high risk of cardiovascular disorders later in life. Women with preeclampsia have activated B cells producing agonistic autoantibodies to AT1‐AA (angiotensin II type I receptor). We hypothesize that rituximab, a B cell‐depleting chemotherapeutic, will deplete maternal B cells in reduced uterine perfusion pressure (RUPP) rats without worsening the effect of placental ischemia on pup growth and survival.

Methods and Results

To test this hypothesis, the RUPP procedure was performed, and rituximab was continuously infused via miniosmotic pump. Maternal blood and tissues were collected. A separate group of dams were allowed to deliver, pup weights were recorded, and at 4 months of age, tissues were collected from offspring. Immune cells were measured via flow cytometry, and AT1‐AA was quantified using a contraction bioassay. Blood pressure increased in RUPP rats and was normalized with rituximab treatment. RUPP offspring also had increased circulating B cells, cytolytic natural killer cells, and increased circulating AT1‐AA, which were normalized with maternal rituximab treatment. This is the first study to analyze the AT1‐AA in RUPP offspring, which was normalized with rituximab.

Conclusions

Our findings indicate that perinatal rituximab lowers maternal mean arterial pressure in RUPP rats and improves birth weight, circulating AT1‐AA, and circulating natural killer cells, indicating that rituximab improves adverse fetal outcomes in response to placental ischemia.