bluuebunny/crossref_metadata_2025_split huggingface dataset:
SMA Micro-Wire Bundle With High Cyclic Actuation Frequency
Authors: Kirsch Susanne-Marie , Welsch Felix , Seelecke Stefan , Motzki Paul 
Published: November 2023

Abstract
Shape memory alloys (SMAs) are an attractive technology in actuators and sensors because of their versatile geometry, low weight, high energy density, and low cost. The design of an SMA actuator system is generally tuned to the desired application criteria during development. Due to the thermal actuation, SMA applications are currently only considered in the frequency ranges below 10 Hz. Replacing cross-sectionally ‘thick’ SMA elements can achieve higher actuation frequencies. The concept of using ‘thin’ elements, thus improving the surface-to-volume ratio, is known from the literature and was translated into applications.
Such a system’s efficient and reliable operation requires the precise combination of the used SMA elements in one system. Replacing the time-consuming and error-prone adjustment process of single SMA elements, a novel bundle concept is developed and presented. One continuous SMA wire is used to build the hole antagonistic system and reaches a cyclic actuation frequency of up to 20 Hz.
This work presents the investigation of the improved bundle concept. Massively reducing the surface-to-volume ratio using very thin SMA wires with a diameter of 25 μm enables the cyclic actuation of up to 66 Hz. In detail, different actuation parameters are discussed to evaluate the cyclic actuation performance.
Soft Actuators From Flexible Auxetic Metamaterials and Shape Memory Alloys Springs
Authors: Woo Janghoon , Abel Julianna 
Published: November 2023

Abstract
Soft robots composed of elastic materials can exhibit nonlinear behaviors, such as variable stiffness and adaptable deformation, that are favorable to cooperation with humans. These characteristics enable soft robots to be used in multiple applications, ranging from minimally invasive surgery and search and rescue in emergency or hazardous environments to marine or space exploration and assistive devices for people with musculoskeletal disorders. Although soft actuators composed of smart materials have been proposed as a control strategy for soft robots, most studies have focused on traditional actuators using hydraulic or pneumatic pressure. Over the years, these have made a lot of progress, but they have not been able to overcome the limitations of the complex configuration of the system and the expansion of the cross-section of the actuator when contracted. This paper merges the actuator design methodology for smart materials with the mechanical analysis of auxetic structures to present an electrically driven soft actuator architecture that achieves reliable actuation displacements. This novel soft actuator, constructed with contractile SMA springs and flexible auxetic metamaterials (FAM), has a spontaneous recovery of the shape after a contraction, a negative Poisson’s ratio, and over 90% of consistency with the performance predictions at the design stage. Our research presents a methodology for the design of a new electrically driven soft actuator, describes the manufacture of SMA springs and FAM, and concludes with the validation of the design by experimental analysis using the 2D planar soft actuator prototype. Finally, our study revealed that the application of the extraordinary characteristics of smart materials and structures together into a single architecture can be a strategy to overcome the limitations of existing soft actuator studies.
Development of Numerical Models Based on Experimental Tests for the Design of Active Vibration Controllers
Authors: Silva Tarcisio , Balasubramanian Prabakaran , Ferrari Giovanni , Hameury Celia , Buabdulla Abdulaziz , Franchini Giulio , Amabili Marco 
Published: November 2023

Abstract
Active Vibration Control (AVC) of electromechanical systems has been an active field of research for decades. One main challenge in AVC techniques is the design of the control laws. In most cases, the design is entirely based on numerical models, thus making high-fidelity models greatly desirable. However, analytical or finite element models are intrinsically onerous and rarely consider imperfections of real-life structures. To overcome this drawback, this work presents a method to obtain a high-fidelity numerical model for electromechanical systems built upon the collection of a set of experimental data. From the experimental responses, the modal mass, damping, stiffness, and electromechanical coupling matrices are determined by using the least square method technique and error minimization. After building the model, the design of a Multiple Input Multiple Output (MIMO) Positive Position Feedback (PPF) control law is presented to mitigate vibrations on a composite panel equipped with 8 non co-located piezoelectric materials and free-free boundary conditions. The tuning of the MIMO controller is carried out completely on the numerical model. Once the tuning is completed, the resulting parameters of the controller are experimentally tested for validation. Experimental results show that the MIMO PPF efficiently reduces vibrations of several modes for both systems, with an overall reduction of nearly 50% compared to the uncontrolled case. In addition, the frequency bandwidth spans more than 150Hz with negligible spillover.
Self-Healing of Fibre-Reinforced Delaminated Composites
Authors: Lanzara Giulia , Porrari Alessandro 
Published: November 2023

Abstract
Taking inspiration from nature allows to engineer materials that possess improved performance, durability and reliability. For instance, living systems repair themselves spontaneously when their biological tissues are injured. Similarly, a material that self-heals when cracked or damaged has the potential to significantly augment its life-time and at the same reduce environmental impact (higher sustainability).
This work is focused on the fabrication of a fibre-reinforced composite, whose aggregating matrix is a thermosetting epoxy resin that is here demonstrated to possess self-healing capability. The composite is designed in such a way to follow the “Close Then Heal” strategy, as for human skin. The chemical and mechanical characterization of the material is discussed, first by studying the bare resin, and then by investigating self-healing of the carbon fiber composite once artificially damaged and re-healed. The study focuses in particular to the most critical failure mode of fibre-reinforced composites: i.e. delamination, which is known to be catastrophic. The results show that the composite self-repairs for a limited number of cycles and that the recovery of the mechanical properties, assessed by comparing the response of the composite before and after cyclic failures/repairs, decreases gradually with the subsequent cycles. The study also shows that the application of pressure allows to reach a more efficient repair, while the microscopic investigation highlights the great potential also in terms of morphological distribution of the fibers within the hosting matrix. The morphology of the re-healed samples is found to be fully recovered with respect to the initial undamaged samples.
An Innovative Multi-Layer System for Thermally Activated Switching Actions
Authors: Hausherr Ginevra , Lanzara Giulia 
Published: November 2023

Abstract
Smart and shape-changing materials are entering a wide range of disciplines including the autonomous activation of devices. Here, a novel thermally driven multifunctional material that works as switch that independently reconfigures itself to trigger an electrical circuit, is presented.
The material consists of multiple polymeric layers that are capable to spontaneously adapt their shape, as a system, when exposed to specific thermal gradients. The multi-layer system hosts in itself an electrically conductive layer. In particular, the film is flat at low temperature and is curved at higher temperature. In this case study the rolled configuration corresponds to the closed circuit (current flow) while the flat configuration corresponds to the opened circuit. The shape changing capability of the film is given by its unique structure which comprises multiple layers (PE and PET) characterized by specific and indeed opposite glass transition temperatures. A key feature of this design is that the material can be “educated” to reach both the desired shape at a specific set temperature, the desired degree and speed of shape change. Moreover, and most importantly, such morphing actions are cyclic without the need of re-educating the material. The study highlights the possibility to fine-tune with repeatability and precision, the shape of the film as a function of temperature.
Effect of Multiple Combination Modes of Reactive Components on the Response of Electromagnetic Vibration Energy Harvester
Authors: Zhong Rui , Thein Chung Ket , Halim Dunant , Xu John 
Published: November 2023

Abstract
As reactive components, capacitors and inductors play an important role in the tuning of energy harvesters, but only a few monotonic connection modes between reactive components and load resistors are usually considered. The impact of diverse connection modes between reactive components and load resistor on energy harvester is worth exploring. In this work, an accurate equivalent circuit model for a specific vibration energy harvester is established. Using this model, the fact that different connection modes have an impact on the response of the energy harvester has been proved. This work provides a reference for setting capacitor and inductor values to maximize load power at fixed applied frequencies. Visual simulation results demonstrate that specific connection modes will cause relatively large load power within a larger range of reactive component parameter settings. At the same time, it is verified that specific connection modes will perform better than other modes under variable applied frequencies, giving reasonable suggestions for the selection of connection modes in this situation.
Design Approach to Particulate-Based Multifunctional Polymer Composite Materials
Authors: Collet Robin , Lynch Christopher S. 
Published: November 2023

Abstract
This paper presents a study on the effect of electrostatic interactions between adjacent dielectric particles. Multifunctional polymer composite materials include a low permittivity matrix material, typically polymer, with dielectric (piezoelectric/ferroelectric) inclusions dispersed throughout. The high permittivity of the inclusions leads to an electric field concentration in the matrix. Interparticle electrostatic interactions arise due to the presence of charged particles in the matrix. These interactions affect the overall properties of the composite. This issue has led to an increasing interest in the electrical properties of multifunctional polymer composite materials. Based on closed-form solution for single inclusion geometries, Finite Element Method (FEM) models are validated. Additional particles of the same geometry are introduced. The electrostatic interactions between particles and the electric field distribution in the composite are studied. Different configurations of particles are presented as well as different particles sizes to assess the effect on the electric field within the particles.
A Hybrid Piezoelectric-Hydraulic Actuator Model and Prototype With Large Stroke and Force Parameters
Authors: Borden Yan , Inman Daniel 
Published: November 2023

Abstract
This paper reports the development of a hybrid piezohydraulic actuator. Piezoelectric stacks provide quick and precise response, when used as actuators. However, their small stroke limits their use to micro- and nano-actuation systems. Mechanical levers are most commonly used to amplify the displacement of a piezo stack, but they sacrifice a significant amount of the blocked force. For the research presented here, a hydraulic system is used to magnify the displacement of piezoelectric stacks, while generating a large blocked force (on the order of kN). This allows the actuator to achieve displacements on the scale of tens of millimeters. Seven piezo stacks push on a piston that moves a hydraulic fluid through a narrowing, which amplifies the stroke of the stacks by the ratio of the wide channel area to the narrow channel area. Since this process decreases the output blocking force by the same ratio, multiple high-force piezo stacks are required to obtain a kN-range blocking force. Hysteresis of the piezo stacks is modeled using a non-symmetrical Bouc-Wen model. A Simulink model of the actuator is constructed and verified using a small-scale prototype. Simulated response characteristics of the proposed actuator as well as drawbacks are also discussed.
Juglone, a plant-derived 1,4-naphthoquinone, binds to hydroxylamine oxidoreductase and inhibits the electron transfer to cytochrome
c
554
Authors: Akutsu Yukie , Fujiwara Takaaki , Suzuki Rintaro , Nishigaya Yuki , Yamazaki Toshimasa 
Published: November 2023

ABSTRACT

Nitrification is an essential biological process that converts ammonia into nitrate via nitrite. In the initial phase of nitrification, ammonia-oxidizing bacteria convert ammonia to hydroxylamine and subsequently to nitrite. The electrons generated in this process provide energy for cellular growth. In this study, we observed the inhibitory effects of plant-derived 1,4-naphthoquinones, including juglone, plumbagin, and 1,4-naphthoquinone, on nitrification in
Nitrosomonas europaea
, a typical nitrifying bacterium. These compounds disrupted the transfer of electrons produced during hydroxylamine oxidation to cytochrome
c
554
, a physiological electron acceptor.
In vitro
electron transfer experiments confirmed the function of these three 1,4-naphthoquinones as electron acceptors in hydroxylamine oxidation. The results indicate that these compounds interfere with electron transfer to cytochrome
c
554
during the ammonia oxidation process leading to nitrification inhibition. Remarkably, lawsone, an isomer of juglone, exhibited no effect on the activity of hydroxylamine oxidoreductase, implying a correlation between the redox potential of each 1,4-naphthoquinone and their ability to hinder canonical electron transfer. Furthermore, X-ray crystallographic analysis revealed that juglone resides in close proximity to the catalytic heme P460 in hydroxylamine oxidoreductase. The hydrophobic environment surrounding the binding cavity appears critical for the selectivity of 1,4-naphthoquinones.

IMPORTANCE

Nitrification, the microbial conversion of ammonia to nitrate via nitrite, plays a pivotal role in the global nitrogen cycle. However, the excessive use of ammonium-based fertilizers in agriculture has disrupted this cycle, leading to groundwater pollution and greenhouse gas emissions. In this study, we have demonstrated the inhibitory effects of plant-derived juglone and related 1,4-naphthoquinones on the nitrification process in
Nitrosomonas europaea
. Notably, the inhibition mechanism is elucidated in which 1,4-naphthoquinones interact with hydroxylamine oxidoreductase, disrupting the electron transfer to cytochrome
c
554
, a physiological electron acceptor. These findings support the notion that phytochemicals can impede nitrification by interfering with the essential electron transfer process in ammonia oxidation. The findings presented in this article offer valuable insights for the development of strategies aimed at the management of nitrification, reduction of fertilizer utilization, and mitigation of greenhouse gas emissions.
Comparative pathogenomic analysis reveals a highly tetanus toxin-producing clade of
Clostridium tetani
isolates in Japan
Authors: Shitada Chie , Sekizuka Tsuyoshi , Yamamoto Akihiko , Sakamoto Chiyomi , Hashino Masanori , Kuroda Makoto , Takahashi Motohide 
Published: November 2023

ABSTRACT

Clostridium tetani
is the etiological agent of the disease tetanus, resulting in various symptoms, including neck tension, tongue-twisting, a decline in walking ability, and death in severe cases. To date, publicly available genome sequences of
C. tetani
are limited.
C. tetani
was isolated from soil in Kumamoto Prefecture, Japan, between 2020 and 2022. Subsequently, bacteriological, biochemical, genetic, and immunological tests were conducted. Among the 46 soil sampling sites, 151
C
.
tetani
strains were isolated from 33 sites, with a 71.7% positivity rate. Comparative genomic analysis subdivided clade 1 into clades 1-1, 1-2, and 1-3. The enzyme-linked immunosorbent assay revealed that partial clade 1-3 strains produced over sevenfold more tetanus neurotoxin (TeNT) than the reference strain (first isolate of
C. tetani
KHSU-154301-001). RNA-Seq analysis supported this elevated tetanus toxin
tetX
gene expression. Additionally,
tetX
-negative strains were isolated from the clade, indicating that TeNT may not be essential for ensuring the survival of their offspring without its representative toxin-causing tetanus. Five strains acquired the tetracycline resistance gene
tet
(M) in the
tetX
plasmid, resulting in significantly reduced susceptibility to tetracycline. In conclusion, although we investigated
C. tetani
isolates from a specific region of the Kumamoto Prefecture, we demonstrated that these isolates exhibit variable genomic features, toxin productivity, and substantial acquired antimicrobial resistance. These findings indicate that multiple
C. tetani
lineages have successfully adapted to the soil in Japan, as evidenced by the additional genome information and toxin productivity assays in this study.

IMPORTANCE

C. tetani
is a spore-forming, anaerobic bacterium that produces a toxin causing muscle stiffness and paralysis. Tetanus is preventable with the toxoid vaccine, but it remains a significant public health threat in regions with low vaccine coverage. However, there are relatively few isolates and limited genomic information available worldwide. In Japan, about 100 cases are reported each year, but there have been no nationwide surveys of isolates, and no genomic information from Japanese isolates has been published. In our study, we analyzed the genomes of 151 strains from a limited survey of soil in Kumamoto, Japan. Our findings revealed a high degree of genetic diversity, and we also identified a subset of strains that produced significantly more toxin, which provides new insights into the pathogenesis of tetanus. Our findings lay the foundation for future studies to investigate the distribution and evolution of
C. tetani
in Japan and neighboring countries.
Nanoobjects for the Luminescence Determination of Fluoroquinolones
Authors: Shtykov S. N. , Smirnova T. D. , Rusanova T. Yu. 
Published: November 2023

Abstract
Fluoroquinolones are the most successful antibiotics, which also show antiviral and antitumor activity. The widespread use of fluoroquinolones in medicine, pharmaceutical chemistry, veterinary medicine and in animal, poultry, and fish feeds requires continuous improvement of methods for their determination in various samples. Sensitized fluorescence based on resonance electronic excitation energy transfer (RET) during the formation of chelates with terbium and europium ions is a promising and highly sensitive method for the determination of fluoroquinolones. This review analyzes the use of two types of nanoobjects—liquid micellar nanosystems and quantum dots based on the nanoparticles of silver, gold, and semiconductors and carbon, magnetic, and other nanomaterials—for increasing the efficiency of energy transfer and the sensitivity of the determination of fluoroquinolones in various samples. The terminology used in the inductive-resonance and exchange-resonance mechanisms of energy transfer is considered, and the fundamental difference in RET between liquid and solid types of nanoobjects is shown. Linear dynamic ranges of determined concentrations, limits of detection, and examples of practical application of sensitized fluorescence to the determination of fluoroquinolones in real samples with the use of nanoparticles and micellar nanosystems are tabulated.
Bronchopulmonary dysplasia: temporal trend from 2010 to 2019 in the Brazilian Network on Neonatal Research
Authors: Stolz Camila , Costa-Nobre Daniela Testoni , Sanudo Adriana , Ferreira Daniela Marques de Lima Mota , Sales Alves José Mariano , dos Santos Julia Paula , Miyoshi Milton Harumi , Silva Nathalia Moura de Mello , Melo Fernanda Pegoraro de Godoi , da Silva Regina Vieira Cavalcanti , Barcala Dafne , Vale Marynea Silva , de Souza Rugolo Ligia Maria Suppo , Diniz Edna Maria Albuquerque , Ribeiro Manoel , Marba Sérgio T M , Cwajg Silvia , Duarte José Luiz Muniz Bandeira , Gonçalves Ferri Walusa Assad , Procianoy Renato S , Anchieta Leni Marcia , de Andrade Lopes José Maria , de Almeida Maria Fernanda B , Guinsburg Ruth 
Published: November 2023

ObjectiveTo evaluate the temporal trend of bronchopulmonary dysplasia (BPD) in preterm infants who survived to at least 36 weeks’ post-menstrual age (PMA) and BPD or death at 36 weeks’ PMA, and to analyse variables associated with both outcomes.DesignRetrospective cohort with data retrieved from an ongoing national registry.Setting19 Brazilian university public hospitals.PatientsInfants born between 2010 and 2019 with 23–31 weeks and birth weight 400–1499 g.Main outcome measuresTemporal trend was evaluated by Prais-Winsten model and variables associated with BPD in survivors or BPD or death were analysed by logistic regression.ResultsOf the 11 128 included infants, BPD in survivors occurred in 22%, being constant over time (annual per cent change (APC): −0.80%; 95% CI: −2.59%; 1.03%) and BPD or death in 45%, decreasing over time (APC: −1.05%; 95% CI: −1.67%; −0.43%). Being male, small for gestational age, presenting with respiratory distress syndrome, air leaks, needing longer duration of mechanical ventilation, presenting with treated patent ductus arteriosus and late-onset sepsis were associated with an increase in the chance of BPD. For the outcome BPD or death, maternal bleeding, multiple gestation, 5-minute Apgar <7, late-onset sepsis, necrotising enterocolitis and intraventricular haemorrhage were added to the variables reported above as increasing the chance of the outcome.ConclusionThe frequency of BPD in survivors was constant and BPD or death decreased by 1.05% at each study year. These results show some improvement in perinatal care in Brazilian units which resulted in a reduction of BPD or death, but further improvements are still needed to reduce BPD in survivors.
Ocular inflammatory events following COVID-19 vaccination: reporting of suspected adverse drug reactions to regulatory authorities in the UK
Authors: Testi Ilaria , Soomro Taha , Pavesio Carlos , Solebo Ameenat Lola 
Published: November 2023

Background/aimsThe UK Medicines and Healthcare products Regulatory Agency (MHRA) has published suspected adverse drug reactions to vaccines against COVID-19. Ocular inflammatory events following COVID-19 vaccination have been reported worldwide.MethodsWe analysed MHRA data on spontaneous reports of suspected ocular inflammatory events following COVID-19 vaccination between January 2021 and September 2022.ResultsThe MHRA received 300 UK spontaneous suspected reports of ocular inflammatory events following COVID-19 vaccination, with a calculated prevalence of 6.6 events per 1 000 000 vaccinated individuals. Anterior uveitis was the most common phenotype (58.3%), followed by optic neuritis in 39.3%. Median number of days between vaccination and onset was 8 days. Resolution of the event was seen in 52.3%.ConclusionOcular inflammatory events following COVID-19 vaccination have a very rare prevalence in the UK. There is no increase in the reporting rate of uveitis, optic neuritis and scleritis following COVID-19 vaccination when compared with the range of incidence in the UK population. The Yellow Card System represents a vital instrument within the domain of pharmacovigilance, empowering patients and healthcare professionals to contribute to the ongoing monitoring of medication safety.