bluuebunny/crossref_metadata_2025 huggingface dataset:
Successful Management of Thyrocervical Trunk Aneurysm Ruptured into the Thoracic Cavity After Cesarean Section in Nonstable Patient with Neurofibromatosis Type I
Authors: Mirković Nikola , Prokić Marko , Novčić Marija , Arsenijević Miloš , Sretenović Snežana , Knežević Dragan , Kovačević Vojin , Šorak Marija , Kostić Olivera
Published: December 2024

Rupture of the thyrocervical trunk aneurysm into the thoracic cavity does not occur very often. It is an urgent condition due to hemorrhagic shock by massive hemothorax with potentially fatal consequences. Pregnancy and puerperium are additional risk factors for a rupture of the thyrocervical trunk aneurysm in patients with neurofibromatosis and aneurysms. This is the first case of thyrocervical trunk aneurysm rupture after a Cesarean section in a patient with neurofibromatosis type I noted down in the literature. The patient, a 33-year-old woman with neurofibromatosis type I, three days after an already performed Cesarean section had acute pain in the left area of the neck, swelling, and a hematoma that progressed rapidly to respiratory distress, hemothorax, and hemorrhagic shock. Emergency endotracheal intubation was performed for airway control. Urgent computer tomography angiography procedure showed extracranial artery, thyrocervical trunk aneurysm rupture, and vertebral aneurysm without rupture. The patient was urgently and successfully treated by endovascular coil embolization of a ruptured thyrocervical trunk aneurysm and subsequently thoracic drainage for massive hemothorax. Postoperatively, her left neck pain decreased, after which she had no further neurologic deficits. The patient was discharged 10 days later. Thyrocervical trunk aneurysm rupture is a rare condition with a potential outcome of death which requires urgent intervention. Endovascular coil embolization is a minimally invasive, safe, and efficient treatment for patients with rupture of thyrocervical trunk aneurysm and following comorbidities.
Dual Repurposing of End-of-Life BWRO Membranes: Ultrafiltration Membranes for Advanced Wastewater Treatment and Cation Exchange Membranes for Fungal Microbial Fuel Cells
Authors: Somrani Anissa , Shabani Mehri , Mohamed Zaineb , Abohelal Kholoud , Alsharari Salam S. , Hannachi Ahmed , Ghaffour Noreddine , Pontié Maxime
Published: December 2024

The objective of this study is to evaluate the degradation of end-of-life BWRO membranes sourced from a factory in France by analyzing their water permeability, roughness, and chemical composition in order to diagnose the level of degradation incurred during their first life cycle in water softening. Following this, two new applications for the end-of-life BWRO membranes were investigated: (i) as ultrafiltration membranes (UF) for domestic effluent treatment and (ii) as cation exchange membranes (CEM) for use in fungal microbial fuel cells (FMFC). The UF membrane was renovated with an acetic acid treatment and, subsequently, used for domestic effluent filtration. The cation exchange membrane was developed in two steps: (i) chlorine treatment and (ii) the deposition of an Amer Sil layer, a functional coating formed by an interpenetrating polymer network (IPN) made of sulfonated polyether sulfone (S-PES) in a cross-linked matrix of acrylic acid and divinylbenzene.
Feature Engineering to Embed Process Knowledge: Analyzing the Energy Efficiency of Electric Arc Furnace Steelmaking
Authors: Zhuo Quantum , Al-Harbi Mansour N. , Pistorius Petrus C.
Published: December 2024

The importance of electric arc furnace (EAF) steelmaking is expected to increase worldwide as parts of the industry transition to lower carbon dioxide emissions. This work analyzed one year’s operational data from an EAF plant that uses a large proportion of direct-reduced iron (DRI) in the furnace feed. The data were used to test different approaches to quantifying the effects of process conditions on specific electricity consumption (kWh per ton of crude steel). In previous work, inputs such as the proportion of DRI, fluxes, natural gas, and oxygen were linearly correlated with the specific electricity consumption. The current work has confirmed that conventional multiple linear regression (MLR) reproduces electricity consumption trends in EAF steelmaking, but many model coefficients deviated significantly from expected values and appeared unphysical. The implementation of engineered features—the slag volume and total carbon input—in an MLR model resulted in coefficients that were closer to expectations, but did not improve prediction accuracy. Further improvement was obtained by applying the engineered features to a non-linear machine-learned model (based on XGBoost), yielding both physically reasonable trends and smaller prediction errors. Trends from Shapley dependence analysis (applied to the XGBoost model) are quantitatively consistent with theoretical trends. These include the energy needed to melt slag, and the endothermic effect of carbon additions. The fitted models demonstrate the potential to diagnose poor slag foaming by showing an increase in electricity consumption with increased oxygen use. This example demonstrates that practically important steelmaking process insights inferred via a linear regression approach can be improved by applying Shapley analysis to a machine-learned model based on engineered features.
Advanced Simulation and Modeling Technologies of Metallurgical Processes—1st Edition
Authors: Li Haifeng , Li Junqi
Published: December 2024

Due to rapid developments in computer technologies over the last two decades, computer-based process modeling has become an important tool for the improvement of existing process technologies and the development of innovative ones [...]
Performance Study of Ultraviolet AlGaN/GaN Light-Emitting Diodes Based on Superlattice Tunneling Junction
Authors: Zhao Zhuang , Liu Yang , Li Peixian , Zhou Xiaowei , Yang Bo , Xiang Yingru , Bai Junchun
Published: December 2024

In this study, we aim to enhance the internal quantum efficiency (IQE) of AlGaN-based ultraviolet (UV) light-emitting diodes (LEDs) by using the short-period AlGaN/GaN superlattice as a tunnel junction (TJ) to construct polarized structures. We analyze in detail the effect of this polarized TJ on the carrier injection efficiency and investigate the increase in hole and electron density caused by the formation of 2D hole gas (2DHG) and 2D electron gas (2DEG) in the superlattice structure. In addition, a dielectric layer is introduced to evaluate the effect of stress changes on the tunneling probability and current spread in TJ. At a current of 140 mA, this method demonstrates effective current expansion. Our results not only improve the performance of UV LEDs but also provide an important theoretical and experimental basis for future research on UV LEDs based on superlattice TJ. In addition, our study also highlights the key role of group III nitride materials in achieving efficient UV luminescence, and the polarization characteristics and band structure of these materials are critical for optimizing carrier injection and recombination processes.
An Approach to Reduce Tuning Sensitivity in the PIC-Based Optoelectronic Oscillator by Controlling the Phase Shift in Its Feedback Loop
Authors: Ivanov Vladislav , Stepanov Ivan , Voronkov Grigory , Kutluyarov Ruslan , Grakhova Elizaveta
Published: December 2024

Radio photonic technologies have emerged as a promising solution for addressing microwave frequency synthesis challenges in current and future communication and sensing systems. One particularly effective approach is the optoelectronic oscillator (OEO), a simple and cost-effective electro-optical system. The OEO can generate microwave signals with low phase noise and high oscillation frequencies, often outperforming traditional electrical methods. However, a notable disadvantage of the OEO compared to conventional signal generation methods is its significant frequency tuning step. This paper presents a novel approach for continuously controlling the output frequency of an optoelectronic oscillator (OEO) based on integrated photonics. This is achieved by tuning an integrated optical delay line within a feedback loop. The analytical model developed in this study calculates the OEO’s output frequency while accounting for nonlinear errors, enabling the consideration of various control schemes. Specifically, this study examines delay lines based on the Mach–Zehnder interferometer and microring resonators, which can be controlled by either the thermo-optic or electro-optic effect. To evaluate the model, we conducted numerical simulations using Ansys Lumerical software. The OEO that utilized an MRR-based electro-optical delay line demonstrated a tuning sensitivity of 174.5 MHz/V. The calculated frequency tuning sensitivity was as low as 6.98 kHz when utilizing the precision digital-to-analog converter with a minimum output voltage step of 40 μV. The proposed approach to controlling the frequency of the OEO can be implemented using discrete optical components; however, this approach restricts the minimum frequency tuning sensitivity. It provides an additional degree of freedom for frequency tuning within the OEO’s operating range, which is ultimately limited by the amplitude-frequency characteristic of the notch filter. Thus, the proposed approach opens up new opportunities for increasing the accuracy and flexibility in generating microwave signals, which can be significant for various communications and radio engineering applications.
Performance Assessment of Ultrascaled Vacuum Gate Dielectric MoS2 Field-Effect Transistors: Avoiding Oxide Instabilities in Radiation Environments
Authors: Tamersit Khalil , Kouzou Abdellah , Rodriguez José , Abdelrahem Mohamed
Published: December 2024

Gate dielectrics are essential components in nanoscale field-effect transistors (FETs), but they often face significant instabilities when exposed to harsh environments, such as radioactive conditions, leading to unreliable device performance. In this paper, we evaluate the performance of ultrascaled transition metal dichalcogenide (TMD) FETs equipped with vacuum gate dielectric (VGD) as a means to circumvent oxide-related instabilities. The nanodevice is computationally assessed using a quantum simulation approach based on the self-consistent solutions of the Poisson equation and the quantum transport equation under the ballistic transport regime. The performance evaluation includes analysis of the transfer characteristics, subthreshold swing, on-state and off-state currents, current ratio, and scaling limits. Simulation results demonstrate that the investigated VGD TMD FET, featuring a gate-all-around (GAA) configuration, a TMD-based channel, and a thin vacuum gate dielectric, collectively compensates for the low dielectric constant of the VGD, enabling exceptional electrostatic control. This combination ensures superior switching performance in the ultrascaled regime, achieving a high current ratio and steep subthreshold characteristics. These findings position the GAA-VGD TMD FET as a promising candidate for advanced radiation-hardened nanoelectronics.
A Robust Normally Closed Pneumatic Valve for Integrated Microfluidic Flow Control
Authors: Li Minggan , Dong Siqin
Published: December 2024

Accurate fluid management in microfluidic-based point-of-care testing (POCT) devices is critical. Fluids must be gated and directed in precise sequences to facilitate desired biochemical reactions and signal detection. Pneumatic valves are widely utilized for fluid gating due to their flexibility and simplicity. However, the development of reliable normally closed pneumatic valves remains challenging, despite their increasing demand in advanced POCT applications to prevent uncontrolled fluid flow. Existing normally closed valves often suffer from poor reliability and lack precise control over fluid opening pressure, due to the uncontrolled stretching of the elastomer during assembly. In this study, we propose and develop a robust method for normally closed valves. By precisely controlling the pre-stretching of the elastomer, we achieve reliable valve closure and accurate control of the opening pressure. A robust normally closed valve was designed and fabricated, and its pneumatic opening pressure was systematically studied. Experimental validations were conducted to demonstrate the reliability and effectiveness of the proposed design.
Slurry Synthesis and Thin-Film Fabrication Toward Production of Li₂O-B₂O₃-Al₂O₃-Based Multilayer Oxide Solid-State Batteries for Internet of Things Applications
Authors: Park Jihyun , Choi Jongmin , Seo Jihye , Nam Wolil , Lee Soobeom , Cho Seungchan , Park Kyungchul , An Geonhyoung , Park Beomkyeong , Choi Moonhee
Published: December 2024

Developing thin-film sheets made of oxide-based solid electrolytes is essential for fabricating surface-mounted ultracompact multilayer oxide solid-state batteries. To this end, solid-electrolyte slurry must be optimized for excellent dispersibility. Although oxide-based solid electrolytes for multilayer structures require sintering, high processing temperatures cause problems such as Li-ion volatilization and reactions with graphite anodes. Thus, low-temperature sinterable oxide-based solid-electrolyte materials should be devised. We successfully developed the conditions for producing thin films from 21 μm thick solid-electrolyte sheets of Li2O-B2O3-Al2O3, one of the most promising candidates for multilayer solid-state batteries. A comprehensive analysis of the fabricated thin films included X-ray diffraction (XRD) to confirm their amorphous structure, scanning electron microscopy (SEM) for particle morphology, and contact angle measurements to verify surface hydrophilicity. Evaluation of a 32-layer bulk sample of solid-electrolyte sheets revealed an ionic conductivity of 2.33 × 10−7 S/cm and charge transfer resistance of 100.1 kΩ at a sintering temperature of 430 °C. Based on these results, cathode and anode active materials will be applied to develop high-energy-density multilayer ceramic batteries with hundreds of layers in future work.
Vector Atomic Magnetometer with Free Induction Decay Detection Based on a Microfabricated Vapor Cell
Authors: Jiang Pengbo , Li Qi , Qin Jianan , Jiang Zhiyuan
Published: December 2024

Atomic magnetometers are highly sensitive instruments widely used for measurements of weak magnetic field. Extracting vector information while maintaining high-precision scalar detection has become the trend in atomic magnetometer development. We introduce a vector atomic magnetometer containing a 5 mm-thick microfabricated vapor cell operating in free-induction-decay mode. By employing orthogonal modulation techniques, the system achieves high-precision in-plane vector magnetic field measurements. The high-precision vector magnetic field measurements are demonstrated in the x–z plane. The sensitivity of the total field detection in the miniaturized atomic magnetometer is 30 pT·Hz−1/2 @11 µT. The average angular error of the decoupled measurement is as low as 4.7 mrad @7.6 µT for vector magnetic fields, providing a new approach for vector magnetic field measurement in miniaturized atomic magnetometers.
Fringe Texture Driven Droplet Measurement End-to-End Network Based on Physics Aberrations Restoration of Coherence Scanning Interferometry
Authors: Zhang Zhou , Chen Jiankui , Yang Hua , Yin Zhouping
Published: December 2024

Accurate and efficient measurement of deposited droplets’ volume is vital to achieve zero-defect manufacturing in inkjet printed organic light-emitting diode (OLED), but it remains a challenge due to droplets’ featurelessness. In our work, coherence scanning interferometry (CSI) is utilized to measure the volume. However, the CSI redundant sampling and image degradation led by the sample’s transparency decrease the efficiency and accuracy. Based on the prior degradation and strong representation for context, a novel method, volume measurement via fringe distribution module (VMFD), is proposed to directly measure the volume by single interferogram without redundant sampling. Firstly, the 3D point spread function (PSF) for CSI imaging is modeling to relate the degradation and image. Secondly, the Zernike to PSF (ZTP) module is proposed to efficiently compute the aberrations to PSF. Then, a physics aberration restoration network (PARN) is designed to remove the degradation via the channel Transformer and U-net architecture. The long term context is learned by PARN and beneficial to restoration. The restored fringes are used to measure the droplet’s volume by constrained regression network (CRN) module. Finally, the performances on public datasets and the volume measurement experiments show the promising deblurring, measurement precision and efficiency.
Biocompatible Heterogeneous Packaging and Laser-Assisted Fluid Interface Control for In Situ Sensor in Organ-on-a-Chip
Authors: Lin Yu-Hsuan , Lau Shing-Fung , Lu Yen-Pei , Huang Kuo-Cheng , Ding Chien-Fang , Tang Yu-Hsiang , Tsai Hsin-Yi
Published: December 2024

The development of bionic organ-on-a-chip technology relies heavily on advancements in in situ sensors and biochip packaging. By integrating precise biological and fluid condition sensing with microfluidics and electronic components, long-term dynamic closed-loop culture systems can be achieved. This study aims to develop biocompatible heterogeneous packaging and laser surface modification techniques to enable the encapsulation of electronic components while minimizing their impact on fluid dynamics. Using a kidney-on-a-chip as a case study, a non-toxic packaging process and fluid interface control methods have been successfully developed. Experimentally, miniature pressure sensors and control circuit boards were encapsulated using parylene-C, a biocompatible material, to isolate biochemical fluids from electronic components. Ultraviolet laser processing was employed to fabricate structures on parylene-C. The results demonstrate that through precise control of processing parameters, the wettability of the material can be tuned freely within a contact angle range of 60° to 110°. Morphological observations and MTT assays confirmed that the material and the processing methods do not induce cytotoxicity. This technology will facilitate the packaging of various miniature electronic components and biochips in the future. Furthermore, laser processing enables rapid and precise control of interface conditions across different regions within the chip, demonstrating a high potential for customized mass production of biochips. The proposed innovations provide a solution for in situ sensing in organ-on-a-chip systems and advanced biochip packaging. We believe that the development of this technology is a critical step toward realizing the concept of “organ twin”.
Designs of Charge-Balanced Edge Termination Structures for 3.3 kV SiC Power Devices Using PN Multi-Epitaxial Layers
Authors: Kim Sangyeob , Seok Ogyun
Published: December 2024

We demonstrated 3.3 kV silicon carbide (SiC) PiN diodes using a trenched ring-assisted junction termination extension (TRA-JTE) with PN multi-epitaxial layers. Multiple P+ rings and width-modulated multiple trenches were utilized to alleviate electric-field crowding at the edges of the junction to quantitively control the effective charge (Qeff) in the termination structures. The TRA-JTE forms with the identical P-type epitaxial layer, which enables high-efficiency hole injection and conductivity modulation. The effects of major design parameters for the TRA-JTE, such as the number of trenches (Ntrench) and depth of trenches (Dtrench), were analyzed to obtain reliable blocking capabilities. Furthermore, the single-zone-JTE (SZ-JTE), ring-assisted-JTE (RA-JTE), and trenched-JTE (T-JTE) were also evaluated for comparative analysis. Our results show that the TRA-JTE exhibited the highest breakdown voltage (BV), exceeding 4.2 kV, and the strongest tolerance against variance in doping concentration for the JTE (NJTE) compared to both the RA-JTE and T-JTE due to the charge-balanced edge termination by multiple P+ rings and trench structures.
Impact of Cell Layout on Bandwidth of Multi-Frequency Piezoelectric Micromachined Ultrasonic Transducer Array
Authors: Yang Wanli , Li Huimin , Gong Yuewu , Wang Zhuochen , Xu Xingli , Hu Xiaofan , Niu Pengfei , Pang Wei
Published: December 2024

Piezoelectric micromachined ultrasonic transducers (PMUTs) show considerable promise for application in ultrasound imaging, but the limited bandwidth of the traditional PMUTs largely affects the imaging quality. This paper focuses on how to arrange cells with different frequencies to maximize the bandwidth and proposes a multi-frequency PMUT (MF-PMUT) linear array. Seven cells with gradually changing frequencies are arranged in a monotonic trend to form a unit, and 32 units are distributed across four lines, forming one element. To investigate how the arrangement of cells affects the bandwidth, three different arrays were designed according to the extent of unit aggregation from the same frequency. Underwater experiments were conducted to assess the acoustic performance, especially the bandwidth. We found that the densest arrangement of the same cells produced the largest bandwidth, achieving a 92% transmission bandwidth and a 50% burst-echo bandwidth at 6 MHz. The mechanism was investigated from the coupling point of view by finite element analysis and laser Doppler vibrometry, focusing on the cell displacements. The results demonstrated strong ultrasound coupling in the devices, resulting in larger bandwidths. To exploit the advanced bandwidth but reduce the crosstalk, grooves for isolation were fabricated between elements. This work proposes an effective strategy for developing advanced PMUT arrays that would benefit ultrasound imaging applications.
Wavefront Correction for Extended Sources Imaging Based on a 97-Element MEMS Deformable Mirror
Authors: Yang Huizhen , Tang Lingzhe , Yan Zhaojun , Chen Peng , Yang Wenjie , Li Xianshuo , Ge Yongqi
Published: December 2024

Adaptive optics (AO) systems are capable of correcting wavefront aberrations caused by transmission media or defects in optical systems. The deformable mirror (DM) plays a crucial role as a component of the adaptive optics system. In this study, our focus is on analyzing the ability of a 97-element MEMS (Micro-Electro-Mechanical System) DM to correct blurred images of extended sources affected by atmospheric turbulence. The RUN optimizer is employed as the control method to evaluate the correction capability of the DM through simulations and physical experiments. Simulation results demonstrate that within 100 iterations, both the normalized gray variance and Strehl Ratio can converge, leading to an improvement in image quality by approximately 30%. In physics experiments, we observe an increase in normalized gray variance (NGV) from 0.53 to 0.97 and the natural image quality evaluation (NIQE) from 15.35 to 19.73, representing an overall improvement in image quality of about 28%. These findings can offer theoretical and technical support for applying MEMS DMs in correcting imaging issues related to extended sources degraded by wavefront aberrations.
Impact of Vein Wall Hyperelasticity and Blood Flow Turbulence on Hemodynamic Parameters in the Inferior Vena Cava with a Filter
Authors: Moradicheghamahi Jafar , Goswami Debkalpa
Published: December 2024

Inferior vena cava (IVC) filters are vital in preventing pulmonary embolism (PE) by trapping large blood clots, especially in patients unsuitable for anticoagulation. In this study, the accuracy of two common simplifying assumptions in numerical studies of IVC filters—the rigid wall assumption and the laminar flow model—is examined, contrasting them with more realistic hyperelastic wall and turbulent flow models. Using fluid–structure interaction (FSI) and computational fluid dynamics (CFD) techniques, the investigation focuses on three hemodynamic parameters: time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), and relative residence time (RRT). Simulations are conducted with varying sizes of clots captured in the filter. The findings show that, in regions of high wall shear stress, the rigid wall model predicted higher TAWSS values, suggesting an increased disease risk compared to the hyperelastic model. However, the laminar and turbulent flow models did not show significant differences in TAWSS predictions. Conversely, in areas of low wall shear stress, the rigid wall model indicated lower OSI and RRT, hinting at a reduced risk compared to the hyperelastic model, with this discrepancy being more evident with larger clots. While the predictions for OSI and TAWSS were closely aligned for both laminar and turbulent flows, divergences in RRT predictions became apparent, especially in scenarios with very large clots.
Enhanced Fluid Mixing in Microchannels Using Levitated Magnetic Microrobots: A Numerical Study
Authors: Demircali Ali Anil , Yilmaz Abdurrahim , Uvet Huseyin
Published: December 2024

The efficient mixing of fluids at microscale dimensions presents challenges due to the dominant laminar flow regime which restricts convective mixing. This study introduces a numerical analysis of a novel microrobotic mixing system with a levitated propeller robot, driven by magnetic fields, within a Y-shaped microchannel with a square cross-section (500 × 500 μm). Our research investigates the fluid mixing effectiveness facilitated by the microrobot through various levitation heights and orientations to enhance the mixing index (MI). This index is tested under different conditions by leveraging the dynamics of the propeller robot, characterized by adjustable roll and pitch angles and varying levitation heights. The numerical simulations, conducted using COMSOL® (Finite Element Method, FEM) software, integrate Maxwell’s equations for magnetic field interaction with momentum and transport-diffusion equations to analyze fluid dynamics within the microchannel. Results indicate that the propeller robot can achieve an MI of up to 98.94% at a 150 μm levitation height and 1500 rpm propeller speed within 3 s. Additionally, the study examines the impact of propeller speed, Reynolds number, and robot length on mixing performance, providing comprehensive guidance for optimizing microscale fluid mixing in lab-on-a-chip applications.
A Concise Review of Recent Advancements in Carbon Nanotubes for Aerospace Applications
Authors: Zecchi Silvia , Cristoforo Giovanni , Piatti Erik , Torsello Daniele , Ghigo Gianluca , Tagliaferro Alberto , Rosso Carlo , Bartoli Mattia
Published: December 2024

Carbon nanotubes (CNTs) have attracted significant attention in the scientific community and in the industrial environment due to their unique structure and remarkable properties, including mechanical strength, thermal stability, electrical conductivity, and chemical inertness. Despite their potential, large-scale applications have been limited by challenges such as high production costs and catalyst contamination. In aerospace applications, CNTs have demonstrated considerable promise either in the form of thin layers or as reinforcements in polymer and metal matrices, where they enhance mechanical, thermal, and electromagnetic performance in lightweight composites. In this short review, we provide an overview of CNTs’ properties and structures, explore CNT growth methods, with a focus on chemical vapor deposition (CVD), and examine their integration into aerospace materials both as films and as multifunctional reinforcements.
MEMS Smart Glass with Larger Angular Tuning Range and 2D Actuation
Authors: Hasan Md Kamrul , Iskhandar Mustaqim Siddi Que , Liebermann Steffen , Baby Shilby , Chen Jiahao , Qasim Muhammad Hasnain , Löber Dennis , Donatiello Roland , Xu Guilin , Hillmer Hartmut
Published: December 2024

Millions of electrostatically actuatable micromirror arrays have been arranged in between windowpanes in inert gas environments, enabling active daylighting in buildings for illumination and climatization. MEMS smart windows can reduce energy consumption significantly. However, to allow personalized light steering for arbitrary user positions with high flexibility, two main limitations must be overcome: first, limited tuning angle spans by MEMS pull-in effects; and second, the lack of a second orthogonal tuning angle, which is highly required. Firstly, design improvements of electrostatically actuatable micromirror arrays are reported by utilizing tailored bottom electrode structures for enlarging the tilt angle (Φ). Considerably larger tuning ranges are presented, significantly improving daylight steering into buildings. Secondly, 2D actuation means free movement of micromirrors via two angles—tilt (Φ) and torsion angle (θ)—while applying two corresponding voltages between the metallic micromirrors and corresponding FTO (fluorine-doped tin oxide) counters bottom electrode pads. In addition, a solution for a notorious problem in MEMS actuation is presented. Micromirror design modifications are necessary to eliminate possible crack formation on metallic structure due to stress concentration during the free movement of 2D actuatable micromirror arrays. The concept, design of micromirror arrays and bottom electrodes, as well as technological fabrication and experimental results are presented and discussed.
Occurrence and Distribution of Microplastics on the Beaches of Limón on the Southern Caribbean Coast of Costa Rica
Authors: Madureira Emanuelle Assunção Loureiro , da Silva André Luiz Carvalho , Barrantes-Castillo Gustavo , de Araújo Fábio Vieira
Published: December 2024

This study aimed to characterize the temporal and spatial occurrence of microplastics on the beaches of the Caribbean coast of Limón, Costa Rica. The selected beaches comprise a stretch of 70 km, characterized by large environmental protection areas, agricultural and residential areas with low occupation density, urban areas, and port areas. Despite the great importance of the beaches for the country, studies related to solid waste pollution remain scarce on the Caribbean coast. The methodology consisted of conducting fieldwork in 2017 and 2019 to collect materials on five beaches and laboratory analyses for extraction using hypersaline solution and the quantification and characterization of microplastics based on type, size, and color. The results show that the beaches studied in the northwestern sector had the highest concentrations of microplastics, with emphasis on Cieneguita Beach and Airport Beach, with a predominance of pellets (56.7%) followed by fragments (21.8%). These beaches are inserted in a coastal stretch with a strong concentration of industrial, port, and airport activities. The lower occurrence of microplastics in the southeastern sector (Manzanillo and Gandoca) may be related to the greater number of preservation areas. With varying sizes, shapes, and colors, most microplastics had a worn appearance, which suggests reworking by coastal processes and subsequent deposition on the studied beaches. The impact of this type of pollution on the coast of Limón is notorious and shows the need for further research into the occurrence and distribution of microplastics on Caribbean beaches so that possible sources and damage to coastal ecosystems can be identified.
Detection and Phylogenetic Analysis of Alphacoronaviruses in Bat Populations of Rostov and Novosibirsk Regions of Russia, 2021–2023
Authors: Ohlopkova Olesia V. , Popov Igor V. , Popov Ilia V. , Stolbunova Kristina A. , Stepanyuk Marina A. , Moshkin Alexey D. , Maslov Aleksei A. , Sobolev Ivan A. , Malinovkin Aleksey V. , Tkacheva Elizaveta V. , Bogdanova Daria A. , Lukbanova Ekaterina A. , Ermakov Alexey M. , Alekseev Alexander Y. , Todorov Svetoslav D. , Shestopalov Alexander M.
Published: December 2024

Bats are natural reservoirs for many emerging viruses, including coronaviruses that were probably progenitors to human coronaviruses with epidemic and pandemic potential, which highlights the importance of screening studies of bat-derived viruses. This study investigates the prevalence and phylogenetic characteristics of coronaviruses in bat populations from the Rostov and Novosibirsk regions of Russia between 2021 and 2023. Utilizing PCR screening and sequencing, viruses belonging to the Alphacoronavirus genus were detected in several bat species, with prevalence rates ranging from 4.94% to 62.5%. Phylogenetic analysis of detected sequences revealed the presence of three subgenera: Pedacovirus, Myotacovirus, and Nyctacovirus. These sequences shared over 90% identity with alphacoronaviruses previously identified in bats across Northern Europe and Russia, underscoring the viruses’ wide geographic distribution and evolutionary connections. The results highlight the adaptability of alphacoronaviruses and the role of bat migratory behavior in their dispersal. The study underscores the importance of continuous monitoring and phylogenetic studies of bat-derived coronaviruses to better understand their ecological dynamics and potential zoonotic threats.
In-Situ Investigation of Copepod Predators of Ichthyophthirius multifiliis Theronts from Fish-Farming Pond
Authors: Wang Lijun , Xi Bingwen , Chen Kai , Xie Jun , Pan Liangkun
Published: December 2024

Ichthyophthirius multifiliis, a parasitic ciliate, causes “white spot disease” in freshwater fish and poses a significant threat to global freshwater aquaculture. Eliminating the free-swimming theront stage from the aquaculture environment is a critical measure for controlling I. multifiliis infections. The natural predator of I. multifiliis theronts in fish-farming ponds were identified using fluorescent dye-labelled live theronts and quantitative PCR; meanwhile, the zooplankton community composition in the positive ponds of I. multifiliis detected by quantitative PCR were analyzed by eDNA metabarcoding assay. The results revealed predation on theronts by cyclopoid copepods, including Cyclops vicinus, Thermocyclops taihokuensis, Cyclops sp., Thermocyclops sp., Eucyclops sp., and Mesocyclops sp. from the in-situ predation aquatic ecosystem, and among these copepods, C. vicinus was identified as a natural dominant predator of I. multifiliis. This study provides a scientific basis for further exploration and utilization of natural predators to enhance sustainable and environmentally friendly control strategies against I. multifiliis.
A Comparison of Rice Root Microbial Dynamics in Organic and Conventional Paddy Fields
Authors: Zhu Fangming , Kamiya Takehiro , Fujiwara Toru , Hashimoto Masayoshi , Gong Siyu , Wu Jindong , Nakanishi Hiromi , Fujimoto Masaru
Published: December 2024

The assembly of plant root microbiomes is a dynamic process. Understanding the roles of root-associated microbiomes in rice development requires dissecting their assembly throughout the rice life cycle under diverse environments and exploring correlations with soil properties and rice physiology. In this study, we performed amplicon sequencing targeting fungal ITS and the bacterial 16S rRNA gene to characterize and compare bacterial and fungal community dynamics of the rice root endosphere and soil in organic and conventional paddy fields. Our analysis revealed that root microbial diversity and composition was significantly influenced by agricultural practices and rice developmental stages (p < 0.05). The root microbiome in the organic paddy field showed greater temporal variability, with typical methane-oxidizing bacteria accumulating during the tillering stage and the amount of symbiotic nitrogen-fixing bacteria increasing dramatically at the early ripening stage. Redundancy analysis identified ammonium nitrogen, iron, and soil organic matter as key drivers of microbial composition. Furthermore, correlation analysis between developmental stage-enriched bacterial biomarkers in rice roots and leaf mineral nutrients showed that highly mobile macronutrient concentrations positively correlated with early-stage biomarkers and negatively correlated with later-stage biomarkers in both paddy fields. Notably, later-stage biomarkers in the conventional paddy field tended to show stronger correlations with low-mobility nutrients. These findings suggest potential strategies for optimizing microbiome management to enhance productivity and sustainability.
Ammonia-Assimilating Bacteria Promote Wheat (Triticum aestivum) Growth and Nitrogen Utilization
Authors: Gao Yuqian , Zhang Qi , Chen Yuannan , Yang Yanqing , Zhou Chenxiao , Yu Jiayang , Li Yanan , Qiu Liyou
Published: December 2024

Nitrogen fertilizers in agriculture often suffer losses. Ammonia-assimilating bacteria can immobilize ammonia and reduce these losses, but they have not been used in agriculture. This study identified an ammonia-assimilating strain, Enterobacter sp. B12, which assimilated ammonia via the glutamate dehydrogenase (GDH) pathway at low levels (5 mM) and the glutamine synthetase (GS)-glutamine-2-oxoglutarate aminotransferase (GOGAT) pathway at high levels (10 mM). Inoculating wheat with B12 increased seedling dry weight, nitrogen accumulation, rhizosphere soil nitrogen content, and root enzyme activities, including GDH, superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), under both conditions. However, root GS, GOGAT enzyme activities, and ammonia assimilation-related gene expressions were lower than the controls. The results suggest that the ammonia-assimilating bacterium promotes wheat growth, nitrogen accumulation, and soil nitrogen immobilization by establishing an ammonia and amino acid exchange with roots and enhancing root antioxidant capacity, making it a potential plant growth-promoting rhizobacteria (PGPR).
Investigating SARS-CoV-2 Neutralising Antibody Response in Sheep
Authors: Samojlović Milena , Mesquita João R. , Santos-Silva Sérgio , Neptin Malin , Esbjörnsson Joakim
Published: December 2024

SARS-CoV-2 can cause clinical and inapparent disease and mortality in several animals cohabitating with humans, and sheep are susceptible to SARS-CoV-2 due to virus–receptor interactions similar to those in humans. Hence, sheep have the potential to be infected, spread, and develop neutralising antibodies (NAbs) against SARS-CoV-2. The aim of this study was to investigate the prevalence of SARS-CoV-2 NAbs in farm animals after natural exposure to the virus. Serum samples were collected from sheep in the Serra da Estrela region in Portugal, both prior to and during the COVID-19 pandemic. The sera were tested by established SARS-CoV-2 pseudovirus systems for multiple SARS-CoV-2 variants (early—Wuhan, mid—Delta, Omicron—BA.1, and late—Omicron XBB, BQ.1.1). Partial neutralisation activity in Pre-pandemic and Mid-pandemic samples was observed, while no NAb activity was observed in Late-pandemic samples tested. Different levels of NAbs were observed between Pre-pandemic samples and those collected during the Mid-pandemic and Late-pandemic periods (p ≤ 0.01). Our results indicate that SARS-CoV-2 cross-species transmission may have occurred through human–sheep contacts on sheep farms during the pandemic, and that farm animals could contribute to the One Health Approach in zoonotic virus surveillance and pandemic preparedness.
The Effect of Mono- and Di-Saccharides on the Microbiome of Dairy Cow Manure and Its Odor
Authors: Loughrin John H. , Agga Getahun E.
Published: December 2024

In a previous experiment, we showed that the odor of Bos taurus manure slurries could be improved by anaerobic incubation with the sugars glucose, lactose, and sucrose. This improvement was due to reductions in the concentrations of malodorants, including dimethyl disulfide, p-cresol, p-ethylphenol, indole, and skatole, and a shift to the production of fruity esters, including ethyl butyrate and propyl propanoate. Due to large concentrations of lactic acid produced by the sugar-amended manure slurries, we inferred that lactic acid bacteria were involved in improving the manure slurry odor. Here, through 16S rRNA amplicon sequencing for microbiome analysis, we show that lactic acid bacterial growth was promoted by the addition of all three sugars. Lactobacillus buchneri and an unknown Lactobacillus sp. were the most prominent lactic acid bacteria stimulated by sugar addition. Lactobacillales were found only in trace abundances in unamended manure slurries. The relative abundance of orders such as Clostridiales, Bifidobacteriales, and Erysipelotrichales were not noticeably affected by sugar amendment. However, the disaccharides lactose and sucrose seemed to increase the relative abundance of Bifidobacterium, whereas the monosaccharide glucose did not. We conclude that lactic acid bacteria are the primary bacteria involved in improving odor in dairy cow manure slurries and present strategies to enhance their abundance in animal wastes.
Geology, Petrology and Geochronology of the Late Cretaceous Klaza Epithermal Deposit: A Window into the Petrogenesis of an Emerging Porphyry Belt in the Dawson Range, Yukon, Canada
Authors: Lee Well-Shen , Kontak Daniel J. , Sack Patrick J. , Crowley James L. , Creaser Robert A.
Published: December 2024

Geologic understanding of the richly mineralized Dawson Range gold belt (DRGB) in the central Yukon, Canada is hindered by: (1) limited outcrop exposure due to thick soil cover; and (2) low resolution age-constraints despite a long history of porphyry Cu–Au–Mo deposit (PCD) exploration. Here, the well-preserved Klaza Au–Ag–Pb–Zn porphyry–epithermal deposit is used as a type-example of Late Cretaceous magmatic–hydrothermal mineralization to address the complex metallogeny of the DRGB. U–Pb zircon dating defines four magmatic pulses of Late Triassic to Late Cretaceous ages with the latter consisting of the Casino (80–72 Ma) and Prospector Mt. (72–65 Ma) suites. The Casino suite has five phases of intermediate-to-felsic calc-alkaline composition, correspond with older (77 Ma) porphyry mineralization, and displays evidence of magma mingling. The intermediate-to-mafic, slightly alkalic Prospector Mt. suite shows evidence of mingling with the youngest Casino suite phases, correlates with younger (71 Ma), intermediate-sulfidation epithermal and porphyry-type mineralization, and shoshonitic basalts of the Carmacks Group. Zircon trace element data suggest a common melt source for these suites; however, the younger suite records features (e.g., high La/Yb) that indicate a higher pressure melt source. The results from this study highlight the Prospector Mt. suite as a historically overlooked causative magma event linked to Au-rich PCDs in the DRGB and extends the temporal window of PCD prospectivity in this area. The transition from mid-Cretaceous Whitehorse suite magmas to Late Cretaceous Casino-Prospector Mt. suite magmas is proposed to reflect a transition from subduction to localized extension, which is becoming more recognized as a common characteristic of productive porphyry belts globally.
Uranium Recovery from Uranium Tailings Using the Low-Temperature Chlorination Roasting and Nitric Acid Leaching Process
Authors: Hu Jinming , Song Jianwei , Hu Tu , Zhang Libo , Wang Yue , Zou Fa
Published: December 2024

To address the problems of low leaching efficiency and the fact that the uranium content in leaching residue is higher than the emission standard in the traditional nitric acid leaching uranium tailing and uranium extraction process, the experimental study of low-temperature chlorination roasting and nitric acid leaching was carried out. The effects of roasting temperature, NaCl addition, and roasting time on uranium leaching rate were investigated, and the morphological structure change and phase transformation of roasted minerals were analyzed. After the low-temperature roasting of sodium chloride, the mineral structure was obviously destroyed, the structure became loose, the voids and microcracks increased, and the size of tailing particles decreased. This is mainly due to the reaction of NaCl with metal compounds in minerals. However, when the sodium chloride is excessive, the formation of hydrogen chloride will promote the formation of new compounds, such as Na2Pb2O7 and Zr7O9F10, and form a secondary coating of uranium, resulting in a decrease in the leaching rate. The optimum process conditions of chlorination roasting are as follows: a roasting temperature 250 °C, a 20% addition of NaCl to the tailing mass, a roasting time of 120 min, and a uranium leaching rate of 93.38%. Compared with traditional nitric acid leaching, the leaching rate of uranium increased by 16.64%.
Clay Mineralogy and Major and Trace Element Geochemistry of Recent Sediments in Rivers Along the West Coast of India: Implications for Provenance and Chemical Weathering
Authors: Babu Shaik Sai , Purnachandra Rao Venigalla , Mohan Mekala Ram
Published: December 2024

The clay mineralogy and major and trace element geochemistry of the sediments deposited at the lower reaches of 90 medium and minor rivers from five states along the west coast of India indicate distinct clay mineral assemblages in the Archean–Proterozoic (A-P) terrain and Deccan Trap (DT) terrain. The sediments from A-P terrain are dominated by kaolinite, with minor illite and gibbsite and traces of goethite, and those from DT terrain are dominated by smectite with minor illite, kaolinite and chlorite. The sediments are depleted of Si, Ca, Mg, Na and K relative to those of Post-Archean average Australian Shale. The SiO2/Al2O3 ratio of the sediments suggests lateritic soils in the A-P terrain and non-lateritic, chemically weathered soils in the DT terrain. Weathering indices indicate strong weathering in the clay fractions of all sediments. The silt fractions of sediments from Goa, Maharashtra and Gujarat exhibit intermediate to weak weathering and influence by hydraulic sorting processes and source rock characteristics. The total trace element content (∑TE) was higher in the silt fractions than in clay fractions of all sediments, and peaks of high ∑TE occur in the silt fractions of Kerala and Maharashtra. The silt fractions exhibit relatively high Th, U, La, Zr and Hf from A-P terrain, and high Sc, Cr, Co, Ni, V and Ga from DT terrain. The Th/U and Rb/Sr ratios are controlled by the intensity of weathering and lithology of source rocks. The standard plots using trace elements reveal that the clay fractions of sediments are more mafic from both the terrains, while silt fractions exhibit intermediate provenance between felsic and mafic sources. Since mafic component-dominated clays are transported to the adjacent seas and oceans, it would be a challenge to identify the provenance of clays from granitic terrain in the oceans using trace element chemistry.
Interaction Mechanisms of Cold Atmospheric Plasmas with HIV Capsid Protein by Reactive Molecular Dynamics Simulation
Authors: Sun Ying , Chen Yang , Zhang Yuantao
Published: December 2024

In recent years, plasma medicine has developed rapidly as a new interdisciplinary discipline. However, the key mechanisms of interactions between cold atmospheric plasma (CAP) and biological tissue are still in the exploration stage. In this study, by introducing the reactive molecular dynamics (MD) simulation, the capsid protein (CA) molecule of HIV was selected as the model to investigate the reaction process upon impact by reactive oxygen species (ROS) from CAP and protein molecules at the atomic level. The simulation results show that ground-state oxygen atoms can abstract hydrogen atoms from protein chains and break hydrogen bonds, leading to the destruction of the disulfide bonds, C–C bonds, and C–N bonds. Furthermore, the generation of alcohol-based groups resulting from the impact of ROS can alter the hydrophobicity of molecules and induce damage to the primary, secondary, and tertiary structures of proteins. The dosage effects on the reaction processes and products induced by CAP are also explored with varying numbers of ROS in the simulation box, and the influences on the broken C–H, N–H, and C–N bonds are discussed. In this study, the computational data suggest that severe damage can be caused to CA upon the impact of ROS by revealing the reaction processes and products.