bluuebunny/crossref_metadata_2025 huggingface dataset:
Deep Reinforcement Learning for Autonomous Driving in Amazon Web Services DeepRacer
Authors: Petryshyn Bohdan , Postupaiev Serhii , Ben Bari Soufiane , Ostreika Armantas
Published: February 2024

The development of autonomous driving models through reinforcement learning has gained significant traction. However, developing obstacle avoidance systems remains a challenge. Specifically, optimising path completion times while navigating obstacles is an underexplored research area. Amazon Web Services (AWS) DeepRacer emerges as a powerful infrastructure for engineering and analysing autonomous models, providing a robust foundation for addressing these complexities. This research investigates the feasibility of training end-to-end self-driving models focused on obstacle avoidance using reinforcement learning on the AWS DeepRacer autonomous race car platform. A comprehensive literature review of autonomous driving methodologies and machine learning model architectures is conducted, with a particular focus on object avoidance, followed by hands-on experimentation and the analysis of training data. Furthermore, the impact of sensor choice, reward function, action spaces, and training time on the autonomous obstacle avoidance task are compared. The results of the best configuration experiment demonstrate a significant improvement in obstacle avoidance performance compared to the baseline configuration, with a 95.8% decrease in collision rate, while taking about 79% less time to complete the trial circuit.
Inflammatory Complications in Chronic Granulomatous Disease
Authors: Grammatikos Alexandros , Gennery Andrew R.
Published: February 2024

Chronic granulomatous disease (CGD) is a rare inborn error of immunity that typically manifests with infectious complications. As the name suggest though, inflammatory complications are also common, often affecting the gastrointestinal, respiratory, urinary tracts and other tissues. These can be seen in all various types of CGD, from X-linked and autosomal recessive to X-linked carriers. The pathogenetic mechanisms underlying these complications are not well understood, but are likely multi-factorial and reflect the body’s attempt to control infections. The different levels of neutrophil residual oxidase activity are thought to contribute to the large phenotypic variations. Immunosuppressive agents have traditionally been used to treat these complications, but their use is hindered by the fact that CGD patients are predisposed to infection. Novel therapeutic agents, like anti-TNFa monoclonal antibodies, anakinra, ustekinumab, and vedolizumab offer promise for the future, while hematopoietic stem cell transplantation should also be considered in these patients.
Screening for Subclinical Atherosclerosis and the Prediction of Cardiovascular Events in People with Type 1 Diabetes
Authors: Serés-Noriega Tonet , Perea Verónica , Amor Antonio J.
Published: February 2024

People with type 1 diabetes (T1D) have a high cardiovascular disease (CVD) risk, which remains the leading cause of death in this population. Despite the improved control of several classic risk factors, particularly better glycaemic control, cardiovascular morbidity and mortality continue to be significantly higher than in the general population. In routine clinical practice, estimating cardiovascular risk (CVR) in people with T1D using scales or equations is often imprecise because much of the evidence comes from pooled samples of people with type 2 diabetes (T2D) and T1D or from extrapolations of studies performed on people with T2D. Given that T1D onsets at a young age, prolonged exposure to the disease and its consequences (e.g., hyperglycaemia, changes in lipid metabolism or inflammation) have a detrimental impact on cardiovascular health. Therefore, it is critical to have tools that allow for the early identification of those individuals with a higher CVR and thus be able to make the most appropriate management decisions in each case. In this sense, atherosclerosis is the prelude to most cardiovascular events. People with diabetes present pathophysiological alterations that facilitate atherosclerosis development and that may imply a greater vulnerability of atheromatous plaques. Screening for subclinical atherosclerosis using various techniques, mainly imaging, has proven valuable in predicting cardiovascular events. Its use enables the reclassification of CVR and, therefore, an individualised adjustment of therapeutic management. However, the available evidence in people with T1D is scarce. This narrative review provides and updated overview of the main non-invasive tests for detecting atherosclerosis plaques and their association with CVD in people with T1D.
Genetic Susceptibility to Arrhythmia Phenotypes in a Middle Eastern Cohort of 14,259 Whole-Genome Sequenced Individuals
Authors: Qafoud Fatima , Elshrif Mohamed , Kunji Khalid , Althani Asma , Salam Amar , Al Suwaidi Jassim , Asaad Nidal , Darbar Dawood , Saad Mohamad
Published: February 2024

Background: The current study explores the genetic underpinnings of cardiac arrhythmia phenotypes within Middle Eastern populations, which are under-represented in genomic medicine research. Methods: Whole-genome sequencing data from 14,259 individuals from the Qatar Biobank were used and contained 47.8% of Arab ancestry, 18.4% of South Asian ancestry, and 4.6% of African ancestry. The frequency of rare functional variants within a set of 410 candidate genes for cardiac arrhythmias was assessed. Polygenic risk score (PRS) performance for atrial fibrillation (AF) prediction was evaluated. Results: This study identified 1196 rare functional variants, including 162 previously linked to arrhythmia phenotypes, with varying frequencies across Arab, South Asian, and African ancestries. Of these, 137 variants met the pathogenic or likely pathogenic (P/LP) criteria according to ACMG guidelines. Of these, 91 were in ACMG actionable genes and were present in 1030 individuals (~7%). Ten P/LP variants showed significant associations with atrial fibrillation p < 2.4 × 10−10. Five out of ten existing PRSs were significantly associated with AF (e.g., PGS000727, p = 0.03, OR = 1.43 [1.03, 1.97]). Conclusions: Our study is the largest to study the genetic predisposition to arrhythmia phenotypes in the Middle East using whole-genome sequence data. It underscores the importance of including diverse populations in genomic investigations to elucidate the genetic landscape of cardiac arrhythmias and mitigate health disparities in genomic medicine.
Effectiveness of Body Weight-Supported Gait Training on Gait and Balance for Motor-Incomplete Spinal Cord Injuries: A Systematic Review with Meta-Analysis
Authors: Arroyo-Fernández Rubén , Menchero-Sánchez Raquel , Pozuelo-Carrascosa Diana P. , Romay-Barrero Helena , Fernández-Maestra Araceli , Martínez-Galán Inés
Published: February 2024

Objective. This review aims to analyse the effectiveness of body weight-supported gait training for improving gait and balance in patients with motor-incomplete spinal cord injuries. Method. Relevant articles were systematically searched in electronic databases to identify randomised controlled trials of body weight-supported gait training (either with methods of robotic, manual, and functional electrical stimulation assistance) versus conventional physical therapy or no intervention. Subjects were >16 years-old with motor-incomplete spinal cord injury (AIS C or D). Primary outcomes were gait-related parameters (functionality, endurance, and speed) and balance. Quality of life was included as a secondary outcome. Articles were selected up to 31 December 2023. Results. Fifteen studies met the inclusion criteria (n = 673). Nine studies used robotic assistance, four trials performed manual assistance, one study functional electrical stimulation assistance, and one trial performed the intervention without guidance. Robot-assisted body weight-supported gait training improved walking functionality (SMD = 1.74, CI 95%: 1.09 to 2.39), walking endurance (MD = 26.59 m, CI 95% = 22.87 to 30.31), and balance (SMD = 0.63, CI 95% = 0.24 to 1.02). Conclusions. Body weight-supported gait training is not superior to conventional physiotherapy in gait and balance training in patients with motor-incomplete spinal cord injury. However, body weight-supported gait training with robotic assistance does improve walking functionality, walking endurance, and balance, but not walking speed.
Are Artificial Intelligence-Assisted Three-Dimensional Histological Reconstructions Reliable for the Assessment of Trabecular Microarchitecture?
Authors: Báskay János , Pénzes Dorottya , Kontsek Endre , Pesti Adrián , Kiss András , Guimarães Carvalho Bruna Katherine , Szócska Miklós , Szabó Bence Tamás , Dobó-Nagy Csaba , Csete Dániel , Mócsai Attila , Németh Orsolya , Pollner Péter , Mijiritsky Eitan , Kivovics Márton
Published: February 2024

Objectives: This study aimed to create a three-dimensional histological reconstruction through the AI-assisted classification of tissues and the alignment of serial sections. The secondary aim was to evaluate if the novel technique for histological reconstruction accurately replicated the trabecular microarchitecture of bone. This was performed by conducting micromorphometric measurements on the reconstruction and comparing the results obtained with those of microCT reconstructions. Methods: A bone biopsy sample was harvested upon re-entry following sinus floor augmentation. Following microCT scanning and histological processing, a modified version of the U-Net architecture was trained to categorize tissues on the sections. Detector-free local feature matching with transformers was used to create the histological reconstruction. The micromorphometric parameters were calculated using Bruker’s CTAn software (version 1.18.8.0, Bruker, Kontich, Belgium) for both histological and microCT datasets. Results: Correlation coefficients calculated between the micromorphometric parameters measured on the microCT and histological reconstruction suggest a strong linear relationship between the two with p-values of 0.777, 0.717, 0.705, 0.666, and 0.687 for BV/TV, BS/TV, Tb.Pf Tb.Th, and Tb.Sp, respectively. Bland–Altman and mountain plots suggest good agreement between BV/TV measurements on the two reconstruction methods. Conclusions: This novel method for three-dimensional histological reconstruction provides researchers with a tool that enables the assessment of accurate trabecular microarchitecture and histological information simultaneously.
Usefulness of Procalcitonin Levels for Predicting the Microbiological Orientation in Patients with Sepsis
Authors: Gómez Natalia Fernanda Pascual , del Pilar Sanz Martín María , Chong María Auxiliadora Semiglia , Cruz Nelly Daniela Zurita , Hernández Rosa Méndez , Molina Iñigo Guerra , Sanz Iñigo García , Tejerina Angels Figuerola , Rueda Fernando Ramasco
Published: February 2024

The main objective of the study was to verify whether levels of procalcitonin (PCT) could guide us toward determining the type of bacteria causing the sepsis and to identify the discriminatory cut-off point in the first urgent laboratory test. This study is a single center retrospective analysis that includes 371 patients with a mean age of 71.7 ± 15.6 years who were diagnosed with sepsis or septic shock. The yield of blood cultures in demonstrating the causative microbiological agent was 24.3% (90), and it was 57, 1% (212) when evaluating all types of cultures. Statistically significant positive differences were observed in the mean value of the PCT between the group that obtained positive cultures and the group that did not (p < 0.0001). The AUC-ROC of PCT values as a guide to the causal bacteria type was 0.68 (95%CI: 0.57–0.78, p < 0.0021). The PCT value that showed the best diagnostic characteristics for identifying Gram-negative rods (GNR) as the causative agent in blood cultures was 2.1 ng/mL. The positive predictive value (PPV) was 78, 9% (66.3–88.1%). The AUC-ROC of the PCT values for sepsis diagnosis, with any positive culture that could be assessed, was 0.67 (95%CI: 0.63–0.73, p < 0.0001). The PCT value that showed the best diagnostic characteristic for predicting sepsis was 3.6 ng/mL.
The Puzzle of Preimplantation Kidney Biopsy Decision-Making Process: The Pathologist Perspective
Authors: Eccher Albino , Becker Jan Ulrich , Pagni Fabio , Cazzaniga Giorgio , Rossi Mattia , Gambaro Giovanni , L’Imperio Vincenzo , Marletta Stefano
Published: February 2024

Kidney transplantation is the best treatment for end-stage renal disease since it offers the greatest survival benefit compared to dialysis. The gap between the number of renal transplants performed and the number of patients awaiting renal transplants leads to a steadily increasing pressure on the scientific community. Kidney preimplantation biopsy is used as a component of the evaluation of organ quality before acceptance for transplantation. However, the reliability and predictive value of biopsy data are controversial. Most of the previously proposed predictive models were not associated with graft survival, but what has to be reaffirmed is that histologic examination of kidney tissue can provide an objective window on the state of the organ that cannot be deduced from clinical records and renal functional studies. The balance of evidence indicates that reliable decisions about donor suitability must be made based on the overall picture. This work discusses recent trends that can reduce diagnostic timing and variability among players in the decision-making process that lead to kidney transplants, from the pathologist’s perspective.
Fine-Tuned Graphene Oxide Nanocomposite: Harnessing Copper(II)–Imidazole Complex for Enhanced Biological Responses and Balanced Photocatalytic Functionality
Authors: Sundaram Ganeshraja Ayyakannu , Kumaravelu Sowndarya , Tseng Wei-Lung , Pham Phuong V. , Kumar Alagarsamy Santhana Krishna , Parimelazhagan Vairavel
Published: February 2024

In this study, the synthesis of biologically active copper(II) complex [Cu(im)2]Cl2 was achieved using a reported method. Subsequently, this copper(II) complex was strategically grafted onto graphene oxide, resulting in the formation of a nanocomposite denoted as copper(II)-complex-grafted graphene oxide (Cu-GO). The comprehensive characterization of Cu-GO was conducted through various techniques, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), UV–visible spectroscopy, emission spectra analysis, X-ray photoelectron spectroscopy (XPS), and Copper K-edge X-ray Absorption Near Edge Structure (XANES) spectroscopy. The antibacterial efficacy of Cu-GO compounds was assessed using disk diffusion and microbroth dilution methods. Notably, the copper complex exhibited the highest effectiveness, showcasing a Minimal Inhibitory Concentration (MIC) value of 500 µL against Klebsiella bacteria. The antibacterial activities of all compounds were systematically screened, revealing the superior performance of the copper complex compared to standalone copper compounds. Expanding the scope of the investigation, we explored the antioxidant and anti-obesity activities of the copper complexes against Klebsiella organisms. The results underscore promising directions for the further exploration of the diverse health-related applications of these compounds. Moreover, the photocatalytic performance of the Cu-GO nanocomposite was evaluated under sunlight irradiation. Notably, the antioxidant and anti-obesity activities of Cu-GO, assessed in terms of percentage inhibition at a concentration of 200 mg/mL, exhibited values of 41% and 45%, respectively. Additionally, the Cu-GO composite exhibited exceptional efficacy, achieving a degradation efficiency of 74% for RhB under sunlight irradiation, surpassing both graphite and GO. These findings not only demonstrate enhanced biological activity, but also highlight a notable level of moderate photocatalytic performance. Such dual functionality underscores the potential versatility of Cu-GO nanocomposites across various applications, blending heightened biological efficacy with controlled photocatalysis. Our study offers valuable insights into the multifunctional attributes of copper(II)-complex-grafted graphene oxide nanocomposites, thereby paving the way for their broader utilization in diverse fields.
Numerical Study on Effect of Aggregate Moisture on Mixing Process
Authors: Cao Guodong , Xie Sheng , Deng Daiqiang , Jiang Shengqiang
Published: February 2024

During the concrete mixing process, the transition of aggregates from a dry to a moist state introduces a crucial dynamic that significantly influences particle interaction, consequently impacting mixing homogeneity. In this paper, based on the discrete element method, the effect of aggregate moisture on the mixing process of sand and stone was investigated. The interaction between dry particles was described by the Hertz–Mindlin model, while the interaction between wet particles was calculated by the linear cohesion model considering the liquid bridge force. Additionally, a functional relationship between the moisture content and the parameters of the linear cohesive contact model was established. The results show that the numerical method can be employed to simulate the mixing process. Notably, when the moisture content of pebbles ranges from 0% to 0.75% and that of sand ranges from 0% to 10.9%, the linear cohesion model is deemed suitable. The standard deviation of the mixing homogeneity of wet particles is lower than that of dry particles for short mixing time, indicating that a small amount of liquid enhances mixing homogeneity. However, moisture has no obvious effect on mixing homogeneity for a long mixing time. This nuanced understanding of the interplay between moisture, particle interactions, and mixing duration contributes valuable insights to optimize concrete mixing processes.
Microscopic Investigation for Experimental Study on Transverse Cracking of Ti-Nb Containing Micro-Alloyed Steels
Authors: Turan Serkan , Shafy Hossam , Palkowski Heinz
Published: February 2024

The influence of Ti on the behavior of hot ductility was examined in four different Ti-containing micro-alloyed steels with a constant content of Nb. Thermomechanical investigations using a dilatometer were carried out to simulate the conditions during casting and cooling in the strand of a continuous caster with temperatures in the range of 650–1100 °C, strain rates of 0.01 s−1 and 0.001 s−1, and reheating rates between 60 and 180 Kmin−1. To understand the fracture mechanism, optical (LOM) and scanning electron microscopy (SEM), elemental analysis via energy dispersive X-ray spectroscopy (EDX), MatCalc “Scheil–Gulliver” calculations, and precipitation kinetics calculations were carried out for the critical conditions, showing low hot ductility between Ar3 and Ae3 temperatures and a brittle to ductile transition temperature at 900 °C. The existence of TiNb(CN), thin ferrite formation, and grain boundary sliding (GBs) due to limited dynamic recrystallization (DRX) has been documented and discussed. As a result, the reheating rate has no sufficient effect on the ductility. The existence of Nb-rich TiNb(CN) of sizes below ~1 μm triggers brittle fracture by increasing the frequency of micro-voids around grain boundaries. It can be stated that if the conditions in the hot ductility trough are avoided, the addition of Ti and high strain support minimize the risk of crack formation.
Comparison of Integrase Strand Transfer Inhibitors (INSTIs) and Protease-Boosted Inhibitors (PIs) on the Reduction in Chronic Immune Activation in a Virally Suppressed, Mainly Male Population Living with HIV (PLWH)
Authors: Nitsotolis Thomas , Kyriakoulis Konstantinos G. , Kollias Anastasios , Papalexandrou Alexia , Kalampoka Helen , Mastrogianni Elpida , Basoulis Dimitrios , Psichogiou Mina
Published: February 2024

Background and Objectives: The success of combined antiretroviral therapy (cART) has led to a dramatic improvement in the life expectancy of people living with HIV (PLWH). However, there has been an observed increase in cardiometabolic, bone, renal, hepatic, and neurocognitive manifestations, as well as neoplasms, known as serious non-AIDS events/SNAEs, compared to the general population of corresponding age. This increase is linked to a harmful phenomenon called inflammaging/immunosenescence, which is driven by chronic immune activation and intestinal bacterial translocation. In this study, we examined immunological and metabolic parameters in individuals receiving current cART. Materials and Methods: The study was conducted at Laiko General Hospital in Athens, Greece. Plasma concentrations of sCD14, IL-6, SuPAR, I-FABP, and LBP were measured in virally suppressed PLWH under cART with at least 350 CD4 lymphocytes/μL. We compared these levels between PLWH receiving integrase strand transfer inhibitors (INSTIs) and protease inhibitors (PIs) and attempted to correlate them with chronic immune activation and metabolic parameters. Results: Data from 28 PLWH were analyzed, with a mean age of 52 and 93% being males. Among the two comparison groups, IL-6 levels were higher in the PIs group (5.65 vs. 7.11 pg/mL, p = 0.03). No statistically significant differences were found in the other measured parameters. A greater proportion of PLWH under INSTIs had normal-range LBP (33% vs. 0%, p = 0.04). When using inverse probability of treatment weighting, no statistically significant differences in the measured parameters were found between the two groups (sCD14 p = 0.511, IL-6 p = 0.383, SuPAR p = 0.793, I-FABP p = 0.868, and LBP p = 0.663). Glucose levels were found to increase after viral suppression in the entire sample (92 mg/dL vs. 98 mg/dL, p = 0.009). Total (191 mg/dL vs. 222 mg/dL, p = 0.005) and LDL cholesterol (104 mg/dL vs. 140 mg/dL, p = 0.002) levels were higher in the PIs group. No significant differences were observed in liver and renal function tests. Conclusions: Further investigation is warranted for PLWH on cART-containing INSTI regimens to explore potential reductions in chronic immune activation and intestinal bacterial translocation.
Improved Corrosion Properties of Mg-Gd-Zn-Zr Alloy by Micro-Arc Oxidation
Authors: Geng Xue , Dong Qiangsheng , Zhang Xiaobo
Published: February 2024

In order to improve the corrosion resistance of Mg-3Gd-1Zn-0.4Zr (GZ31K) alloys for biomedical application, the alloy was micro-arc oxidation (MAO)-treated using silicate electrolyte system under various voltages (400 V, 425 V, 450 V, 475 V). The effects of voltage on the microstructure and corrosion properties of MAO coating were investigated via X-ray diffraction (XRD) and a scanning electron microscope (SEM) combined with an energy-dispersive spectrometer (EDS), X-ray photoelectron spectroscope (XPS), and electrochemical experiments. The results showed that, with the increase in voltage, the MAO coatings became thicker and the micropores on the MAO coating increased in diameter. The main phase compositions of the MAO coatings were MgO and Mg2SiO4. Potentiodynamic polarization curve results showed that MAO coatings could enhance corrosion resistances, where the corrosion current density decreased by six orders of magnitude and the corrosion potential of the specimens increased by 300 mV for the voltage of 450 V in the MAO treatment; nevertheless, the corrosion resistance rapidly deteriorated due to the creation of large micropores in the MAO coating, which provide a pathway for corrosive media when the voltage is 475 V. The electrochemical impedance spectroscopy results showed that MAO treatments could increase low-frequency modulus resistance and increase the corrosion resistance of Mg alloys. In addition, MAO-treated GZ31K alloys still exhibited uniform corrosion, which is desirable for biomedical applications.
Atomic-Scale Dislocation Structure Evolution and Crystal Ordering Analysis of Melting and Crystallization Microprocesses in Laser Powder Bed Melting of γ-TiAl Alloys
Authors: Gu Bangjie , Wang Quanlong , Ma Chenglong , Han Lei , Wei Wentao , Li Xiao
Published: February 2024

Laser Powder Bed Fusion (LPBF) technology exhibits significant advantages in the manufacturing of components with high dimensional accuracy and intricate internal cavities. However, due to the inherent room-temperature brittleness and high-temperature gradient induced by the laser forming process, the LPBF fabrication of γ-TiAl alloy is often accompanied by the initiation and propagation of defects. The aim of this study is to investigate the forming process of γ-TiAl alloy by the LPBF method through molecular dynamics simulation, and to explain the microparticle arrangement and displacement evolution of the melting and crystallization processes, thus elucidating the link between the variations in the laser process parameters and defect generation during microscopic laser heating. The results show that during the melting process, the peaks of the radial distribution function (RDF) decrease rapidly or even disappear due to laser heating, and the atomic disorder is increased. Although subsequent cooling crystallization reorders the atomic arrangement, the peak value of the RDF after crystallization is still 19.3% lower than that of the original structure. By setting different laser powers (200–800 eV/ps) and scanning speeds (0.2–0.8 Å/ps), the effects of various process parameters on microforming and defect evolution are clarified. When the laser power increases from 200 to 400 eV/ps, the stable value of atomic displacement rises from 6.66 to 320.87, while it rises from 300.54 to 550.14 when the scanning speed is attenuated from 0.8 to 0.4 Å/ps, which indicates that, compared with the scanning speed, the atomic mean-square displacements are relatively more sensitive to the fluctuation of laser power. Dislocation analysis reveals that a higher laser power significantly increases the cooling rate during the forming process, which further aggravates the generation and expansion of dislocation defects.
metabCombiner 2.0: Disparate Multi-Dataset Feature Alignment for LC-MS Metabolomics
Authors: Habra Hani , Meijer Jennifer L. , Shen Tong , Fiehn Oliver , Gaul David A. , Fernández Facundo M. , Rempfert Kaitlin R. , Metz Thomas O. , Peterson Karen E. , Evans Charles R. , Karnovsky Alla
Published: February 2024

Liquid chromatography–high-resolution mass spectrometry (LC-HRMS), as applied to untargeted metabolomics, enables the simultaneous detection of thousands of small molecules, generating complex datasets. Alignment is a crucial step in data processing pipelines, whereby LC-MS features derived from common ions are assembled into a unified matrix amenable to further analysis. Variability in the analytical factors that influence liquid chromatography separations complicates data alignment. This is prominent when aligning data acquired in different laboratories, generated using non-identical instruments, or between batches from large-scale studies. Previously, we developed metabCombiner for aligning disparately acquired LC-MS metabolomics datasets. Here, we report significant upgrades to metabCombiner that enable the stepwise alignment of multiple untargeted LC-MS metabolomics datasets, facilitating inter-laboratory reproducibility studies. To accomplish this, a “primary” feature list is used as a template for matching compounds in “target” feature lists. We demonstrate this workflow by aligning four lipidomics datasets from core laboratories generated using each institution’s in-house LC-MS instrumentation and methods. We also introduce batchCombine, an application of the metabCombiner framework for aligning experiments composed of multiple batches. metabCombiner is available as an R package on Github and Bioconductor, along with a new online version implemented as an R Shiny App.
Integration Technology with Thin Films Co-Fabricated in Laminated Composite Structures for Defect Detection and Damage Monitoring
Authors: Langat Rogers K. , De Luycker Emmanuel , Cantarel Arthur , Rakotondrabe Micky
Published: February 2024

Despite the well-established nature of non-destructive testing (NDT) technologies, autonomous monitoring systems are still in high demand. The solution lies in harnessing the potential of intelligent structures, particularly in industries like aeronautics. Substantial downtime occurs due to routine maintenance, leading to lost revenue when aircraft are grounded for inspection and repairs. This article explores an innovative approach using intelligent materials to enhance condition-based maintenance, ultimately cutting life-cycle costs. The study emphasizes a paradigm shift toward structural health monitoring (SHM), utilizing embedded sensors for real-time monitoring. Active thin film piezoelectric materials are proposed for their integration into composite structures. The work evaluates passive sensing through acoustic emission (AE) signals and active sensing using Lamb wave propagation, presenting amplitude-based and frequency domain approaches for damage detection. A comprehensive signal processing approach is presented, and the damage index and damage size correlation function are introduced to enable continuous monitoring due to their sensitivity to changes in material properties and defect severity. Additionally, finite element modeling and experimental validation are proposed to enhance their understanding and applicability. This research contributes to developing more efficient and cost-effective aircraft maintenance approaches through SHM, addressing the competitive demands of the aeronautic industry.
Evolution of the Microrobots: Stimuli-Responsive Materials and Additive Manufacturing Technologies Turn Small Structures into Microscale Robots
Authors: den Hoed Frank Marco , Carlotti Marco , Palagi Stefano , Raffa Patrizio , Mattoli Virgilio
Published: February 2024

The development of functional microsystems and microrobots that have characterized the last decade is the result of a synergistic and effective interaction between the progress of fabrication techniques and the increased availability of smart and responsive materials to be employed in the latter. Functional structures on the microscale have been relevant for a vast plethora of technologies that find application in different sectors including automotive, sensing devices, and consumer electronics, but are now also entering medical clinics. Working on or inside the human body requires increasing complexity and functionality on an ever-smaller scale, which is becoming possible as a result of emerging technology and smart materials over the past decades. In recent years, additive manufacturing has risen to the forefront of this evolution as the most prominent method to fabricate complex 3D structures. In this review, we discuss the rapid 3D manufacturing techniques that have emerged and how they have enabled a great leap in microrobotic applications. The arrival of smart materials with inherent functionalities has propelled microrobots to great complexity and complex applications. We focus on which materials are important for actuation and what the possibilities are for supplying the required energy. Furthermore, we provide an updated view of a new generation of microrobots in terms of both materials and fabrication technology. While two-photon lithography may be the state-of-the-art technology at the moment, in terms of resolution and design freedom, new methods such as two-step are on the horizon. In the more distant future, innovations like molecular motors could make microscale robots redundant and bring about nanofabrication.
Batch Fabrication of Microelectrode Arrays with Glassy Carbon Microelectrodes and Interconnections for Neurochemical Sensing: Promises and Challenges
Authors: Faul Emma-Bernadette A. , Broussard Austin M. , Rivera Daniel R. , Pwint May Yoon , Wu Bingchen , Cao Qun , Bailey Davis , Cui X. Tracy , Castagnola Elisa
Published: February 2024

Flexible multielectrode arrays with glassy carbon (GC) electrodes and metal interconnection (hybrid MEAs) have shown promising performance in multi-channel neurochemical sensing. A primary challenge faced by hybrid MEAs fabrication is the adhesion of the metal traces with the GC electrodes, as prolonged electrical and mechanical stimulation can lead to adhesion failure. Previous devices with GC electrodes and interconnects made of a homogeneous material (all GC) demonstrated exceptional electrochemical stability but required miniaturization for enhanced tissue integration and chronic electrochemical sensing. In this study, we used two different methods for the fabrication of all GC-MEAs on thin flexible substrates with miniaturized features. The first method, like that previously reported, involves a double pattern-transfer photolithographic process, including transfer-bonding on temporary polymeric support. The second method requires a double-etching process, which uses a 2 µm-thick low stress silicon nitride coating of the Si wafer as the bottom insulator layer for the MEAs, bypassing the pattern-transfer and demonstrating a novel technique with potential advantages. We confirmed the feasibility of the two fabrication processes by verifying the practical conductivity of 3 µm-wide 2 µm-thick GC traces, the GC microelectrode functionality, and their sensing capability for the detection of serotonin using fast scan cyclic voltammetry. Through the exchange and discussion of insights regarding the strengths and limitations of these microfabrication methods, our goal is to propel the advancement of GC-based MEAs for the next generation of neural interface devices.
How Possible Is the Elimination of Viral Hepatitis? An Analysis Based on the Global Burden of Disease from Hepatitis B and C, 1990–2019
Authors: Alvis-Guzman Nelson , Alvis-Zakzuk Nelson J. , De la Hoz Restrepo Fernando
Published: February 2024

This study assesses the feasibility of hepatitis B (HBV) and C (HCV) elimination using an analysis of trends of epidemiology data (1990–2019) from the Global Burden of Disease Study. Joinpoint regression analysis was used to identify significantly changing points in the trends of Age-standardized Prevalence Rates (ASPR) and Age-standardized Mortality Rates (ASMR) and to estimate the annual percentage changes (APC) and the average annual percentage changes (AAPC) for the period. The Sociodemographic Index (SDI) was used to analyze trends between countries. The total percentage change of the ASPR (2019/1990) was −31.4% and −12.8% for HBV and HCV worldwide, respectively; the rate ratio (HBV/HCV) was 2.5. Mortality had decreased for HBV but not for HCV. The total percentage change for the ASMR (2019/1990) was −26.7% and 10.0% for HBV and HCV, respectively. While the ASMR of HBV decreased, HCV increased during this period. The percentage change in ASMR of HBV was highest in countries with high–middle SDI and lowest in countries with high SDI. For HCV, the percentage change in ASMR was highest in countries with high SDI (increase), and only in countries with low SDI did it decrease. The global HBV and HCV rates have fallen with different AAPCs associated with the SDI. Despite the advances, there is still a long way to go to achieve the 2030 elimination goals. An important challenge is related to finding a way to speed up the yearly rate at which the decline is happening.
Coupled Microstructural EBSD and LA-ICP-MS Trace Element Mapping of Pyrite Constrains the Deformation History of Breccia-Hosted IOCG Ore Systems
Authors: King Samuel Anthony , Cook Nigel John , Ciobanu Cristiana Liana , Ehrig Kathy , Campo Rodriguez Yuri Tatiana , Basak Animesh , Gilbert Sarah
Published: February 2024

Electron backscatter diffraction (EBSD) methods are used to investigate the presence of microstructures in pyrite from the giant breccia-hosted Olympic Dam iron–oxide copper gold (IOCG) deposit, South Australia. Results include the first evidence for ductile deformation in pyrite from a brecciated deposit. Two stages of ductile behavior are observed, although extensive replacement and recrystallization driven by coupled dissolution–reprecipitation reaction have prevented widespread preservation of the earlier event. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) element maps of pyrite confirm that many pyrite grains display compositional zoning with respect to As, Co, and Ni, but that the zoning is often irregular, patchy, or otherwise disrupted and are readily correlated with observed microstructures. The formation of ductile microstructures in pyrite requires temperatures above ~260 °C, which could potentially be related to heat from radioactive decay and fault displacements during tectonothermal events. Coupling EBSD methods with LA-ICP-MS element mapping allows a comprehensive characterization of pyrite textures and microstructures that are otherwise invisible to conventional reflected light or BSE imaging. Beyond providing new insights into ore genesis and superimposed events, the two techniques enable a detailed understanding of the grain-scale distribution of minor elements. Such information is pivotal for efforts intended to develop new ways to recover value components (precious and critical metals), as well as remove deleterious components of the ore using low-energy, low-waste ore processing methods.
Morphological Design and Synthesis of Nanoparticles
Authors: Honciuc Mirela , Honciuc Andrei
Published: February 2024

Nanoparticles are particles with dimensions measured in nanometers, and exist at a scale where the physical, chemical, and biological properties of materials can differ significantly from those at a larger scale [...]
Topographic Distribution of miRNAs (miR-30a, miR-223, miR-let-7a, miR-let-7f, miR-451, and miR-486) in the Plasma Extracellular Vesicles
Authors: Petrova Tatiana , Kalinina Olga , Aquino Arthur , Grigoryev Evgeniy , Dubashynskaya Natallia V. , Zubkova Kseniya , Kostareva Anna , Golovkin Alexey
Published: February 2024

There are many articles on the quantitative analysis of miRNAs contained in a population of EVs of different sizes under various physiological and pathological conditions. For such analysis, it is important to correctly quantify the miRNA contents of EVs. It should be considered that quantification is skewed depending on the isolation protocol, and different miRNAs are degraded by nucleases with different efficiencies. In addition, it is important to consider the contribution of miRNAs coprecipitating with the EVs population, because the amount of miRNAs in the EVs population under study is skewed without appropriate enzymatic treatment. By studying a population of EVs from the blood plasma of healthy donors, we found that the absolute amount of miRNA inside the vesicles is commensurate with the amount of the same type of miRNA adhered to the outside of the EVs. The inside/outside ratio ranged from 1.02 to 2.64 for different investigated miRNAs. According to our results, we propose the hypothesis that high occupancy of miRNAs on the outer surface of EVs influence on the transporting RNA repertoire no less than the inner cargo received from the host cell.
Potential Therapeutic Effects of Bifidobacterium breve MCC1274 on Alzheimer’s Disease Pathologies in AppNL-G-F Mice
Authors: Abdelhamid Mona , Jung Cha-Gyun , Zhou Chunyu , Inoue Rieko , Chen Yuxin , Sento Yoshiki , Hida Hideki , Michikawa Makoto
Published: February 2024

We previously demonstrated that orally supplemented Bifidobacterium breve MCC1274 (B. breve MCC1274) mitigated Alzheimer’s disease (AD) pathologies in both 7-month-old AppNL-G-F mice and wild-type mice; thus, B. breve MCC1274 supplementation might potentially prevent the progression of AD. However, the possibility of using this probiotic as a treatment for AD remains unclear. Thus, we investigated the potential therapeutic effects of this probiotic on AD using 17-month-old AppNL-G-F mice with memory deficits and amyloid beta saturation in the brain. B. breve MCC1274 supplementation ameliorated memory impairment via an amyloid-cascade-independent pathway. It reduced hippocampal and cortical levels of phosphorylated extracellular signal-regulated kinase and c-Jun N-terminal kinase as well as heat shock protein 90, which might have suppressed tau hyperphosphorylation and chronic stress. Moreover, B. breve MCC1274 supplementation increased hippocampal synaptic protein levels and upregulated neuronal activity. Thus, B. breve MCC1274 supplementation may alleviate cognitive dysfunction by reducing chronic stress and tau hyperphosphorylation, thereby enhancing both synaptic density and neuronal activity in 17-month-old AppNL-G-F mice. Overall, this study suggests that B. breve MCC1274 has anti-AD effects and can be used as a potential treatment for AD.
Mapping the Silent Threat: A Comprehensive Analysis of Chagas Disease Occurrence in Riverside Communities in the Western Amazon
Authors: Paixão Daniela da Silva , Portela Madeira Fernanda , Costa de Jesus Adila , Paixão Hêmilly Caroline da Silva , Camargo Juliana de Souza Almeida Aranha , Ribeiro Mariane Albuquerque Lima , José Ramos Leandro , de Oliveira Jader , Aristeu da Rosa João , Bernarde Paulo Sérgio , Pereira Relvas Antonieta , Basano Sergio de Almeida , Aranha Camargo Luis Marcelo , Meneguetti Dionatas Ulises de Oliveira
Published: February 2024

Chagas disease (CD) is a typical tropical illness caused by Trypanosoma cruzi. The objective of this study was to assess the prevalence of Chagas disease in communities in two states of the Brazilian Amazon. Data collection occurred in July in the Alto Juruá region of Acre and in December in the communities of Humaitá, Amazonas, in 2019. A total of 477 participants were included in the study. In the communities of Alto Juruá, triatomine collections and analyses of T. cruzi infection were also carried out. All confirmed cases were found in the state of Acre, resulting in a total prevalence of 1.67. Of these eight cases, seven underwent ECG, all of which were concluded as normal by the physician team’s cardiologists. Seventeen triatomine bugs, all belonging to the Rhodnius genus, were captured. The natural infection rate by T. cruzi was 25% in the Nova Cintra community and 66.67% in the Boca do Moa community (Alto Juruá). This research found that more than 1% of the studied population exhibited positive serological results for Chagas disease in the riverine communities during the study period, representing a small portion of cases among those who have not yet been diagnosed.
Zika Virus—A Reemerging Neurotropic Arbovirus Associated with Adverse Pregnancy Outcomes and Neuropathogenesis
Authors: Elliott Kenneth C. , Mattapallil Joseph J.
Published: February 2024

Zika virus (ZIKV) is a reemerging flavivirus that is primarily spread through bites from infected mosquitos. It was first discovered in 1947 in sentinel monkeys in Uganda and has since been the cause of several outbreaks, primarily in tropical and subtropical areas. Unlike earlier outbreaks, the 2015–2016 epidemic in Brazil was characterized by the emergence of neurovirulent strains of ZIKV strains that could be sexually and perinatally transmitted, leading to the Congenital Zika Syndrome (CZS) in newborns, and Guillain-Barre Syndrome (GBS) along with encephalitis and meningitis in adults. The immune response elicited by ZIKV infection is highly effective and characterized by the induction of both ZIKV-specific neutralizing antibodies and robust effector CD8+ T cell responses. However, the structural similarities between ZIKV and Dengue virus (DENV) lead to the induction of cross-reactive immune responses that could potentially enhance subsequent DENV infection, which imposes a constraint on the development of a highly efficacious ZIKV vaccine. The isolation and characterization of antibodies capable of cross-neutralizing both ZIKV and DENV along with cross-reactive CD8+ T cell responses suggest that vaccine immunogens can be designed to overcome these constraints. Here we review the structural characteristics of ZIKV along with the evidence of neuropathogenesis associated with ZIKV infection and the complex nature of the immune response that is elicited by ZIKV infection.
Novel Synthesis Approach for Natural Tea Polyphenol-Integrated Hydroxyapatite
Authors: Ren Xiaoxiang , Yi Zeng , Li Xudong
Published: February 2024

Hydroxyapatite (HAP) has garnered considerable interest in biomedical engineering for its diverse applications. Yet, the synthesis of HAP integrated with functional natural organic components remains an area ripe for exploration. This study innovatively utilizes the versatile properties of tea polyphenol (TP) to synthesize HAP nanomaterials with superior crystallinity and distinct morphologies, notably rod-like structures, via a chemical deposition process in a nitrogen atmosphere. This method ensures an enhanced integration of TP, as confirmed by thermogravimetric (TGA) analysis and a variety of microscopy techniques, which also reveal the dependence of TP content and crystallinity on the synthesis method employed. The research significantly impacts the field by demonstrating how synthesis conditions can alter material properties. It leads the way in employing TP-modified nano-HAP particles for biomedical applications. The findings of this study are crucial as they open avenues for the future development of tailored HAP nanomaterials, aiming at specific medical applications and advancements in nanotechnology.
Recent Developments in CaCO3 Nano-Drug Delivery Systems: Advancing Biomedicine in Tumor Diagnosis and Treatment
Authors: Lin Chenteng , Akhtar Muhammad , Li Yingjie , Ji Min , Huang Rongqin
Published: February 2024

Calcium carbonate (CaCO3), a natural common inorganic material with good biocompatibility, low toxicity, pH sensitivity, and low cost, has a widespread use in the pharmaceutical and chemical industries. In recent years, an increasing number of CaCO3-based nano-drug delivery systems have been developed. CaCO3 as a drug carrier and the utilization of CaCO3 as an efficient Ca2+ and CO2 donor have played a critical role in tumor diagnosis and treatment and have been explored in increasing depth and breadth. Starting from the CaCO3-based nano-drug delivery system, this paper systematically reviews the preparation of CaCO3 nanoparticles and the mechanisms of CaCO3-based therapeutic effects in the internal and external tumor environments and summarizes the latest advances in the application of CaCO3-based nano-drug delivery systems in tumor therapy. In view of the good biocompatibility and in vivo therapeutic mechanisms, they are expected to become an advancing biomedicine in the field of tumor diagnosis and treatment.