bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation and measurement of square strip line antenna design and characteristic mode analysis for 5G/WiFi/WLAN applications
Authors: Albargi Hasan B , Bhatt Pranav , Borisagar Komal R , Kotak Nirali , Jalalah Mohammed , Almawgani Abdulkarem H M , Lavadiya Sunil , Patel Shobhit K
Published: April 2024

Two novel compact low-profile dual-band plasmonic antennas designed using Characteristic Mode Analysis (CMA) and parametric analysis are presented in this study. The plasmonic antennas contain microstrip line-fed strip-loaded patches and partial ground planes. The final proposed antennas cover the two bands ranging from 2.4–2.5 GHz and 5–6 GHz. Plasmonic antennas offer nearly omnidirectional patterns at the desired frequency ranges. Additionally, a detailed parametric study of almost all the design parameters is performed to display the effect of varying those parameters on the resonance frequency at both bands. The parametric study for both antennas has been carried out to optimize the antenna and get better-enhanced results. Then the fabricated antenna is analyzed for the same. The comparison results of fabrication show nearly similarity results to the simulated results. The designed antenna can be applicable for 5G/ Wi-Fi/WLAN applications.
The Goldstone Apple Valley Radio Telescope (GAVRT) Search for Extra Terrestrial Intelligence (SETI)
Authors: Gorjian Varoujan , Levin Steven , Arballo John , Timmaraju Virisha , Dorcey Ryan , Kreuser-Jenkins Nancy , Lamb Lisa , Lazio Joseph , Webb-Mack Zoe
Published: April 2024

This paper reports the results from a student-led Search for Extraterrestrial Intelligence (SETI), also known as technosignatures, targeting the plane of the Milky Way as a part of the Goldstone Apple Valley Radio Telescope (GAVRT) collaboration between the Lewis Center for Educational Research (LCER) and the Jet Propulsion Laboratory. Students associated with LCER submit analytic reports of spectral data targeting specific regions of the Milky Way, identifying interference, noise, and Candidate signals potentially originating from intelligent sources. GAVRT-SETI's search is guided by the assumption that a narrow-band radio signal (<1.5 Hz) from a fixed location in the sky, occurring across multiple observation periods, is unlikely to be caused by instrument noise or by a natural source. Thus, we searched the reported data for similar signals occurring during different observation periods within the same region of sky. No such signals were found. However, our analysis of the frequency distribution of Candidates suggests that at least a few percent of the Candidates are associated with low-level radio-frequency interference.
MSLTE: multiple self-supervised learning tasks for enhancing EEG emotion recognition
Authors: Li Guangqiang , Chen Ning , Niu Yixiang , Xu Zhangyong , Dong Yuxuan , Jin Jing , Zhu Hongqin
Published: April 2024

Objective. The instability of the EEG acquisition devices may lead to information loss in the channels or frequency bands of the collected EEG. This phenomenon may be ignored in available models, which leads to the overfitting and low generalization of the model. Approach. Multiple self-supervised learning tasks are introduced in the proposed model to enhance the generalization of EEG emotion recognition and reduce the overfitting problem to some extent. Firstly, channel masking and frequency masking are introduced to simulate the information loss in certain channels and frequency bands resulting from the instability of EEG, and two self-supervised learning-based feature reconstruction tasks combining masked graph autoencoders (GAE) are constructed to enhance the generalization of the shared encoder. Secondly, to take full advantage of the complementary information contained in these two self-supervised learning tasks to ensure the reliability of feature reconstruction, a weight sharing (WS) mechanism is introduced between the two graph decoders. Thirdly, an adaptive weight multi-task loss (AWML) strategy based on homoscedastic uncertainty is adopted to combine the supervised learning loss and the two self-supervised learning losses to enhance the performance further. Main results. Experimental results on SEED, SEED-V, and DEAP datasets demonstrate that: (i) Generally, the proposed model achieves higher averaged emotion classification accuracy than various baselines included in both subject-dependent and subject-independent scenarios. (ii) Each key module contributes to the performance enhancement of the proposed model. (iii) It achieves higher training efficiency, and significantly lower model size and computational complexity than the state-of-the-art (SOTA) multi-task-based model. (iv) The performances of the proposed model are less influenced by the key parameters. Significance. The introduction of the self-supervised learning task helps to enhance the generalization of the EEG emotion recognition model and eliminate overfitting to some extent, which can be modified to be applied in other EEG-based classification tasks.
Numerical simulation study on the embedding depth of anti slip piles in fully weathered granite landslides
Authors: Yu Peng , Zhang Jike , Jia Shixiang , Cao Lei , Zhao Lei
Published: April 2024

Taking the reinforcement project of the fully weathered granite landslide in Fanling as the research object, this study establishes a numerical slope model with anti-slide pile reinforcement, the most common means in slope reinforcement engineering, while considering the pile-soil interaction. Using the strength reduction method, the effects of different anti-slide pile embedment depth on the stability of the reinforced slope are discussed. The research results indicate the following findings. (1) The embedment depth is negatively correlated with the slope displacement. (2) When the embedment depth is more excellent than 7m, the slope Factor of safety is 2.032>2.0, which meets engineering safety requirements. (3) According to the changes in displacement and the factor of safety, the stress analyses of the pile body and the economic factors, the optimal embedment depth for the Fanling landslide are determined as 8 m. The results afford certain application and promotion values by providing theoretical references and technical guidance for similar anti-slide pile reinforced slope projects.
Hardware-Accelerated YOLOv5 Based on MPSoC
Authors: Liu Junjiang , Mao Mingyu , Gao Jianlong , Bai Jiangtao , Sun Dandan
Published: April 2024

This paper details the development of a hardware acceleration system for YOLOv5, focusing on flame detection as its primary application. The implementation leverages the APU and DPU functionalities integrated into the Zynq UltraScale+ MPSoC XCZU7EV core. The proposed solution addresses the challenge of achieving real-time target detection on mobile terminals, ensuring both real-time operation and ultralow power consumption of YOLOv5. Notably, our design approach facilitates the deployment of all target detection algorithms under TensorFlow for mobile devices. To optimize model efficiency, we employ saturated linear mapping quantization with calibration. This technique maps model weights, double bases, and activations from 32-bit to 8-bit, incurring only a 1.64% accuracy loss. The data flow design is realized through efficient data exchange between DDR, APU, and DPU, utilizing the AXI4 bus architecture. Image pre-processing and post-processing tasks are executed on the APU, while neural network inference occurs on the DPU. Our accelerated system demonstrates compelling experimental results: maintaining a detection speed of 56FPS, achieving an accuracy of 36.56% on the COCO2014 dataset, and exhibiting a total system power consumption of only 4.147W. Furthermore, the energy consumption ratio is measured at 15.41GOPS/W, surpassing the RTX A6000 graphics card by a factor of 55.
Study on Vibration Adjustment Mechanism of S-76D Helicopter Rotor System Based on HUMS System
Authors: Zheng Xiaofeng , Sun Ting
Published: April 2024

In recent years, helicopter maintenance technology has been developing rapidly and is transitioning from time-based periodic maintenance to condition-based maintenance. Helicopter Health and Usage Monitoring System (HUMS system) plays an important role in this process. The excitation forces originating from the helicopter rotor system are the primary cause of airframe vibration, and the HUMS system monitors the main rotor balance and trajectory data during each flight and provides an adjustment solution and predicts the vibration level in case of overruns. This paper summarizes the vibration measurement, cause analysis and vibration adjustment methods by studying the vibration adjustment mechanism of the S-76D helicopter rotor system, and provides solution for the same type of vibration problems of the helicopter.
Study on Preparation and Application Technology of Micro scale New Foam Ceramics for Power Equipment
Authors: Zhang Shiling , He Yongsheng , Lu Zongxiang , Deng Baojia
Published: April 2024

With the proposal of a new type of power system in China, the new environment-friendly insulating medium micro nano foam ceramic is urgently needed to replace SF6, epoxy resin and other insulating materials in the GIS/GIL key power equipment. The new material technology can prepare: foam ceramic design method. Preparation method of foam ceramics and the functional modulation of micro/nano structures. The electrical performance of the foam ceramics was improved. Achievable: the stable performance of micro/nano structures under the high field strength. Excellent thermal conductivity under high current action. It has local replacement function in insulation material applications such as SF6 and epoxy resin. Detectable: Starting from the electrical performance of the UHV hybrid insulation material system, UHF technology and photo-acoustic spectroscopy technology are applied to the high sensitivity detection of the decomposition products and partial discharges of foam ceramics, focusing on types of fluorocarbon decomposition gases, making use of strong correlation between the decomposition products and the partial discharge detection data, and combining the multi-source data fusion algorithm to achieve the prediction of insulation structure data sequence and online detection of the latent faults for the special GIS/GIL.
Spatial-Temporal Graph Deviation Neural Networks for Anomaly Detection in Time Series
Authors: Guo Ziyu , Kong Weiyang , Liu Yubao
Published: April 2024

Anomaly detection in time series data (e.g., sensor data) is becoming a fundamental research problem that has various applications. Due to the complex inter-sensor relationships, it is challenging to detect anomalous events such as system faults and attacks hidden the high-dimensional time series. Recent advancements in deep learning approaches such as Graph Neural Networks (GNN) have greatly improved anomaly detection performance in time series data. However, existing methods usually use separate components to capture spatial and temporal dependence relationship and ignore the heterogeneities in spatial-temporal data which motivates us to capture them together. In this paper, we propose a novel approach STGDNN (short for Spatial-Temporal Graph Deviation Neural Networks) that learns the spatial-temporal dependence relationship together in structure learning of graph neural networks. In addition, we use the learned spatial-temporal graph structure and attention weights to explain the detected anomalies. The experiments on three real world datasets show our superiority in detection accuracy, anomaly diagnosis, and model interpretation compared with state-of-the-art methods.
Portable ratiometric fluorescence detection of Cu2+ and thiram
Authors: Zhang Jiazhen , Jia Yicong , Tong Xuan , Zhou Hangyu , Zhang Le , Yang Yue , Ji Xu
Published: April 2024

Food contaminants pose a danger to human health, but rapid, sensitive and reliable food safety detection methods can offer a solution to this problem. In this study, an optical fiber ratiometric fluorescence sensing system based on carbon dots (CDs) and o-phenylenediamine (OPD) was constructed. The ratiometric fluorescence response of Cu2+ and thiram was carried out by the fluorescence resonance energy transfer (FRET) between CDs and 2,3−diaminophenazine (ox-OPD, oxidized state o-phenylenediamine). The oxidation of OPD by Cu2+ resulted in the formation of ox-OPD, which quenched the fluorescence of CDs and exhibited a new emission peak at 573 nm. The formation of a [dithiocarbamate-Cu2+] (DTC-Cu2+) complex by reacting thiram with Cu2+, inhibits the OPD oxidation reaction triggered by Cu2+, thus turning off the fluorescence signal of OPD-Cu2+. The as-established detection system presented excellent sensitivity and selectivity for the detection of Cu2+ and thiram in the ranges of 1 ∼ 100 μM and 5 ∼ 50 μM, respectively. The lowest detection limits were 0.392 μM for Cu2+ and 0.522 μM for thiram. Furthermore, actual sample analysis indicated that the sensor had the potential for Cu2+ and thiram assays in real sample analysis.
Effect of sodium dodecyl sulfate (SDS) on the co-deposition and frictional behavior of carbon nanotube/nickel composite layer
Authors: Liu Yingnan , Yang Ping , Li Yuxin , Xiao Yi , Shu Baipo
Published: April 2024

In this paper, the effects of sodium dodecyl sulfate (SDS) concentrations in the electroplating solution on the morphology, nucleation rate, nucleation mode, and frictional behavior of the CNT/Ni composite layers were investigated. The results showed that the electrodeposition of Ni was in a three-dimensional nucleation/growth mode. In addition, the x-ray diffraction (XRD) of the deposited layers showed that adding SDS changed the preferred growth direction of Ni from (2 0 0) to the (2 2 0) crystallographic plane. When the carbon nanotube (CNT) content was 0.1 g l−1, and the SDS content was 0.05 g l−1, the deposition potential was the most negative, increasing the number of Ni nucleation sites on the electrode and resulting in the grain size refinement of the deposited layer. It also reduced the friction coefficient of the composite simultaneously.
Development of CuO nanoparticles modified electrochemical sensor for detection of salbutamol
Authors: Koc Delice Tulay , Ak Azem Funda , Ozdemir Kazim , Alpat Senol
Published: April 2024

Metal oxide structures are being utilized in an increasing variety of applications. This study used cyclic and differential pulse voltammetry techniques to investigate the possible utilization of copper oxide (CuO) nanoparticles modified carbon paste electrode (CPE) for the redox reactions of salbutamol (SAL). The electrochemical performance of the SAL analyte in a complex matrix environment in Ventolin was evaluated in order to assess the appropriateness of the proposed sensor in a real sample environment. CuO nanoparticles were produced via a straightforward, cost-effective and efficient sol–gel method, and characterization studies of synthesized CuO nanoparticles were performed by scanning electron microscopy, x-ray Diffraction (XRD), and x-ray photoelectron spectroscopy. The synthesized CuO nanoparticles had a spherical shape and particle size was found to be 74 nm. The crystal size of the CuO particles was calculated to be 21.79 nm using the Debye–Scherrer equation. Under optimal conditions, differential pulse voltammetry demonstrated a linear response in the 50 nM to 100 μM range, with a salbutamol detection limit of 50 nM (S/N = 3). The SAL concentration (R
2 = 0.9971) was found to have a good correlation coefficient. The reproducibility of the biosensor was investigated and evaluated with a relative standard deviation of 3% (n = 8). The storage stability of CuO modified CPE for two weeks was evaluated based on the response of DP current measured at intervals every two days. According to the measurement results, the modified electrode exhibited good stability and reproducibility while maintaining 80% of its stability. It is also a rapid and dependable sensor candidate with a measurement time of approximately 20 s. The developed electrode has been utilized successfully to determine doping material with improved performance.
Reconfigurable screen-printed terahertz frequency selective surface based on metallic checkerboard pattern
Authors: Ahmad Redwan , Ropagnol Xavier , Trinh Ngoc Duc , Bois Chloé , Blanchard François
Published: April 2024

We employed the screen-printing method to fabricate terahertz (THz) frequency selective surfaces (FSSs) featuring an inductive metallic checkerboard (i-MCB) pattern based on conductive silver ink onto a flexible polyethylene terephthalate substrate, chosen for its excellent THz transmission properties below 1 THz [Jin et al 2006 J. Korean Phys. Soc.
49 513–17]. Analytical studies, along with simulations and experiments, were conducted to investigate the filtering characteristics of the printed FSSs, confirming their functionality as a band-pass filter. Subsequently, we demonstrated the reconfigurability of a two-layer system by vertically stacking two layers. This was achieved by systematically shifting the position of the second layer in the x or y-direction relative to the first layer. Experimental verification revealed a significant variation in normalized transmission, ranging from 94% to 6% at 0.15 THz for type-I:i-MCBs and 90% to 5% at 0.20 THz for type-II:i-MCBs, respectively. This study presents a simple scheme for a reconfigurable screen-printed i-MCB-FSS operating in the THz range. Consequently, our findings demonstrate that screen printing method can effectively be employed for the large-scale production of THz FSSs.
Enhancing reversible Na-ion intercalation by introducing K-ions into layered vanadyl phosphate for sodium-ion battery cathodes
Authors: Wei Runzhe , Lu Yi , Ren Wanjun , Han Yupei , Vijaya Kumar Saroja Ajay Piriya , Xia Xueming , He Pan , Nason Charlie A F , Sun Zhixin , Darr Jawwad A , Luo Jiayan , Zhou Min , Xu Yang
Published: April 2024

Vanadium-based phosphates are being extensively studied as an important family of sodium-ion battery (SIB) cathodes. Among many compositions, NaVOPO4 is considered because of various polymorphs and the high redox potential of V4+/5+. However, due to relatively poor intrinsic kinetics and electronic conductivity, approaches such as nanostructuring and carbon composites are commonly used to avoid fast performance degradation. Being different from mainstream approaches, this work utilizes the knowledge gained from potassium-ion batteries (PIBs) and applies layered KVOPO4, a PIB cathode material, as a SIB cathode material. The results demonstrate that KVOPO4 experiences an electrochemical K+-Na+ exchange during the initial cycle and a Na-dominated (de)intercalation process in the following cycles. The initial exchange results in a small amount of K+ (∼0.1 K per formula) remaining in the interlayer space and owing to the larger size of K+ than Na+, the residual K+ effectively acts as ‘pillars’ to expand interlayer spacing and facilitates the Na (de)intercalation, leading to enhanced reversible Na storage and diffusion kinetics of KVOPO4 compared to its Na counterpart NaVOPO4. KVOPO4 delivers an initial discharge capacity of 120 mAh g−1 (90% of the theoretical capacity) at 10 mA g−1 and retains 88% capacity after 150 cycles. It also delivers 52 mAh g−1 at 1 A g−1 and 91% capacity retention after 1000 cycles at 100 mA g−1, completely outperforming NaVOPO4.
Methodological examination of the 2018 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) Score
Authors: Shams-White Marissa M , Thompson E Christi , Carroll Raymond J , Reedy Jill
Published: April 2024

The objective of this study was to examine the impact of methodological changes to the 2018 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) Score on associations with risk for all-cause mortality, cancer mortality, and cancer risk jointly among older adults in the National Institutes of Health (NIH)-AARP Diet and Health Study. Weights were incorporated for each score component; a continuous point scale was developed in place of the score’s fully discrete cut points; and cut-point values were changed for physical activity and red meat based on evidence-based recommendations. Exploratory aims also examined the impact of separating components with more than one subcomponent and whether all components were necessary to retain within this population utilizing a penalized scoring approach. Findings suggested weighting the original 2018 WCRF/AICR Score improved its predictive performance in association with all-cause mortality and provided more precise estimates in relation to cancer risk and mortality outcomes. The importance of healthy weight, physical activity, and plant-based foods in relation to cancer and overall mortality risk were highlighted in this population of older adults. Further studies are needed to better understand the consistency and generalizability of these findings across other populations.
Internal validation of gestational age estimation algorithms in health-care databases using pregnancies conceived through fertility procedures
Authors: Chiu Yu-Han , Huybrechts Krista F , Zhu Yanmin , Straub Loreen , Bateman Brian T , Logan Roger , Hernández-Díaz Sonia
Published: April 2024

Fertility procedures recorded in health-care databases can be used to estimate the start of pregnancy, which can serve as a reference standard to validate gestational age estimates based on International Classification of Diseases codes. In a cohort of 17 398 US MarketScan pregnancies (2011-2020) in which conception was achieved via fertility procedures, we estimated gestational age at the end of pregnancy using algorithms based on (1) time (days) since the fertility procedure (the reference standard); (2) International Classification of Diseases, Ninth Revision (ICD-9)/International Classification of Diseases, Tenth Revision (ICD-10) (before/after October 2015) codes indicating gestational length recorded at the end of pregnancy (method A); and (3) ICD-10 end-of-pregnancy codes enhanced with Z3A codes denoting specific gestation weeks recorded at prenatal visits (method B). We calculated the proportion of pregnancies with an estimated gestational age falling within 14 days ($\pm$14 days) of the reference standard. Method A accuracy was similar for ICD-9 and ICD-10 codes. After 2015, method B was more accurate than method A: For term births, within–14-day agreement was 90.8% for method A and 98.7% for method B. Corresponding estimates were 70.1% and 95.6% for preterm births; 35.3% and 92.6% for stillbirths; 54.3% and 64.2% for spontaneous abortions; and 16.7% and 84.6% for elective terminations. ICD-10–based algorithms that incorporate Z3A codes improve the accuracy of gestational age estimation in health-care databases, especially for preterm births and non–live births.
Sexual selection and species recognition promote complex male courtship displays in ungulates
Authors: D’Ammando Giacomo , Bro-Jørgensen Jakob
Published: April 2024

Identifying the evolutionary drivers of sexual signal complexity is a key challenge in the study of animal communication. Among mammals, male bovids and cervids often perform elaborate gestural displays during courtship, consisting of ritualized movements of various parts of the body but the causes underlying interspecific variation in complexity of such displays remain poorly understood. Here we apply the comparative method to investigate which factors may have either promoted or constrained gestural repertoire size. We found that sexual selection was a strong predictor of gestural display complexity in male bovids and cervids. Repertoire size was positively correlated with breeding group size, an indicator of the intensity of sexual selection in males. Moreover, repertoires were larger in species adopting nonterritorial and lek breeding mating systems than in species adopting resource-defence territoriality, a finding that can be explained by more emphasis on direct benefits than indirect benefits in resource-defence systems, where male mating success may also be less skewed due to difficulty in monopolizing mates. The results also indicate that gestural repertoire size was positively correlated with the number of closely related species occurring in sympatry. This is consistent with display complexity being selected to facilitate species recognition during courtship and thereby avoid interspecific hybridization. At the same time, repertoire size was negatively associated with male body mass, possibly due to the energetic and mechanical constraints imposed on movements in very large species. By contrast, we found no evidence that the habitat drives selection for complex gestural courtship displays.
Improving the performance of supervised deep learning for regulatory genomics using phylogenetic augmentation
Authors: Duncan Andrew G , Mitchell Jennifer A , Moses Alan M
Published: April 2024

Motivation

Supervised deep learning is used to model the complex relationship between genomic sequence and regulatory function. Understanding how these models make predictions can provide biological insight into regulatory functions. Given the complexity of the sequence to regulatory function mapping (the cis-regulatory code), it has been suggested that the genome contains insufficient sequence variation to train models with suitable complexity. Data augmentation is a widely used approach to increase the data variation available for model training, however current data augmentation methods for genomic sequence data are limited.

Results

Inspired by the success of comparative genomics, we show that augmenting genomic sequences with evolutionarily related sequences from other species, which we term phylogenetic augmentation, improves the performance of deep learning models trained on regulatory genomic sequences to predict high-throughput functional assay measurements. Additionally, we show that phylogenetic augmentation can rescue model performance when the training set is down-sampled and permits deep learning on a real-world small dataset, demonstrating that this approach improves data efficiency. Overall, this data augmentation method represents a solution for improving model performance that is applicable to many supervised deep-learning problems in genomics.

Availability and implementation

The open-source GitHub repository agduncan94/phylogenetic_augmentation_paper includes the code for rerunning the analyses here and recreating the figures.
Caudate functional networks influence brain structural changes with aging
Authors: Basaia Silvia , Zavarella Matteo , Rugarli Giulia , Sferruzza Giacomo , Cividini Camilla , Canu Elisa , Cacciaguerra Laura , Bacigaluppi Marco , Martino Gianvito , Filippi Massimo , Agosta Federica
Published: April 2024

Neurogenesis decline with aging may be associated with brain atrophy. Subventricular zone neuron precursor cells possibly modulate striatal neuronal activity via the release of soluble molecules. Neurogenesis decay in the subventricular zone may result in structural alterations of brain regions connected to the caudate, particularly to its medial component. The aim of this study was to investigate how the functional organization of caudate networks relates to structural brain changes with aging. One hundred and fifty-two normal subjects were recruited: 52 young healthy adults (≤35 years old), 42 middle-aged (36 ≤ 60 years old) and 58 elderly subjects (≥60 years old). In young adults, stepwise functional connectivity was used to characterize regions that connect to the medial and lateral caudate at different levels of link-step distances. A statistical comparison between the connectivity of medial and lateral caudate in young subjects was useful to define medial and lateral caudate connected regions. Atrophy of medial and lateral caudate connected regions was estimated in young, middle-aged and elderly subjects using T1-weighted images. Results showed that middle-aged and elderly adults exhibited decreased stepwise functional connectivity at one-link step from the caudate, particularly in the frontal, parietal, temporal and occipital brain regions, compared to young subjects. Elderly individuals showed increased stepwise functional connectivity in frontal, parietal, temporal and occipital lobes compared to both young and middle-aged adults. Additionally, elderly adults displayed decreased stepwise functional connectivity compared to middle-aged subjects in specific parietal and subcortical areas. Moreover, in young adults, the medial caudate showed higher direct connectivity to the basal ganglia (left thalamus), superior, middle and inferior frontal and inferior parietal gyri (medial caudate connected region) relative to the lateral caudate. Considering the opposite contrast, lateral caudate showed stronger connectivity to the basal ganglia (right pallidum), orbitofrontal, rostral anterior cingulate and insula cortices (lateral caudate connected region) compared to medial caudate. In elderly subjects, the medial caudate connected region showed greater atrophy relative to the lateral caudate connected region. Brain regions linked to the medial caudate appear to be more vulnerable to aging than lateral caudate connected areas. The adjacency to the subventricular zone may, at least partially, explain these findings. Stepwise functional connectivity analysis can be useful to evaluate the role of the subventricular zone in network disruptions in age-related neurodegenerative disorders.
Dopaminergic mesolimbic structural reserve is positively linked to better outcome after severe stroke
Authors: Asmussen Liv , Frey Benedikt M , Frontzkowski Lukas K , Wróbel Paweł P , Grigutsch L Sophie , Choe Chi-un , Bönstrup Marlene , Cheng Bastian , Thomalla Götz , Quandt Fanny , Gerloff Christian , Schulz Robert
Published: April 2024

The concept of brain reserve capacity has emerged in stroke recovery research in recent years. Imaging-based biomarkers of brain health have helped to better understand outcome variability in clinical cohorts. Still, outcome inferences are far from being satisfactory, particularly in patients with severe initial deficits. Neurorehabilitation after stroke is a complex process, comprising adaption and learning processes, which, on their part, are critically influenced by motivational and reward-related cognitive processes. Amongst others, dopaminergic neurotransmission is a key contributor to these mechanisms. The question arises, whether the amount of structural reserve capacity in the dopaminergic system might inform about outcome variability after severe stroke. For this purpose, this study analysed imaging and clinical data of 42 severely impaired acute stroke patients. Brain volumetry was performed within the first 2 weeks after the event using the Computational Anatomy Toolbox CAT12, grey matter volume estimates were collected for seven key areas of the human dopaminergic system along the mesocortical, mesolimbic and nigrostriatal pathways. Ordinal logistic regression models related regional volumes to the functional outcome, operationalized by the modified Rankin Scale, obtained 3–6 months after stroke. Models were adjusted for age, lesion volume and initial impairment. The main finding was that larger volumes of the amygdala and the nucleus accumbens at baseline were positively associated with a more favourable outcome. These data suggest a link between the structural state of mesolimbic key areas contributing to motor learning, motivational and reward-related brain networks and potentially the success of neurorehabilitation. They might also provide novel evidence to reconsider dopaminergic interventions particularly in severely impaired stroke patients to enhance recovery after stroke.
Synthesis and electrochemical properties of Li5+xFe1–xMnxO4 with an antifluorite-type structure as a lithium battery cathode
Authors: Goto Ryosuke , Taminato Sou , Mori Daisuke , Imanishi Nobuyuki
Published: April 2024

A new antifluorite-structured Li5+xFe1–xMnxO4 was synthesized by conventional solid-state reaction and the lithium (de-)intercalation properties were characterized from electrochemical measurements. A single phase with a Li6MnO4-type structure was obtained for the x ≥ 0.6 compositions. The first discharge capacity of a Li5.6Fe0.4Mn0.6O4 (x = 0.6) electrode treated by ball milling was 450 mAh/g. The reversible reaction continued to proceed with ca. 200 mAh/g after subsequent cycles. A new iron–manganese system with an antifluorite structure could be a potential candidate as a high-capacity cathode material.
A clinical score to predict recovery in end-stage kidney disease due to acute kidney injury
Authors: Shah Silvi , Ng Jia H , Leonard Anthony C , Harrison Kathleen , Meganathan Karthikeyan , Christianson Annette L , Thakar Charuhas V
Published: April 2024

Background

Acute kidney injury (AKI) is a major contributor to end-stage kidney disease (ESKD). About one-third of patients with ESKD due to AKI recover kidney function. However, the inability to accurately predict recovery leads to improper triage of clinical monitoring and impacts the quality of care in ESKD.

Methods

Using data from the United States Renal Data System from 2005 to 2014 (n = 22 922), we developed a clinical score to predict kidney recovery within 90 days and within 12 months after dialysis initiation in patients with ESKD due to AKI. Multivariable logistic regressions were used to examine the effect of various covariates on the primary outcome of kidney recovery to develop the scoring system. The resulting logistic parameter estimates were transformed into integer point totals by doubling and rounding the estimates. Internal validation was performed.

Results

Twenty-four percent and 34% of patients with ESKD due to AKI recovered kidney function within 90 days and 12 months, respectively. Factors contributing to points in the two scoring systems were similar but not identical, and included age, race/ethnicity, body mass index, congestive heart failure, cancer, amputation, functional status, hemoglobin and prior nephrology care. Three score categories of increasing recovery were formed: low score (0–6), medium score (7–9) and high score (10–12), which exhibited 90-day recovery rates of 12%, 26% and 57%. For the 12-month scores, the low, medium and high groups consisted of scores 0–5, 6–8 and 9–11, with 12-month recovery rates of 16%, 33% and 62%, respectively. The internal validation assessment showed no overfitting of the models.

Conclusion

A clinical score derived from information available at incident dialysis predicts renal recovery at 90 days and 12 months in patients with presumed ESKD due to AKI. The score can help triage appropriate monitoring to facilitate recovery and begin planning long-term dialysis care for others.
Usefulness of the heart rate variability test in predicting intradialytic hypotension in patients undergoing chronic haemodialysis
Authors: Park Yohan , Lee Ji Won , Yoon Se-Hee , Hwang Won Min , Yun Sung-Ro , Son Ji-Young , Chung Byung Ha , Min Jiwon
Published: April 2024

Background

Intradialytic hypotension (IDH) is the primary complication of haemodialysis (HD); however, its diverse pathophysiology and inconsistent definitions complicate its prediction. Despite attempts using the heart rate variability (HRV) test for IDH prediction, studies on its usefulness for predicting IDH diagnosed per the nadir 90 criterion are lacking. We aimed to evaluate HRV test efficacy and reproducibility in predicting IDH based on the nadir 90 criterion.

Methods

Seventy patients undergoing HD participated in this multicentre prospective observational study. The HRV test was performed during non-HD periods and IDH was monitored during 12 HD sessions. IDH was diagnosed according to the nadir 90 criterion, defined as a decrease in systolic blood pressure of ≤90 mmHg during HD. After monitoring, the HRV test was repeated. An HRV–IDH index was developed using multivariate logistic regression analysis employing HRV test parameters. The predictive power of the HRV–IDH index was analysed using the area under the receiver operating characteristics curve (AUROC). Reproducibility was evaluated using correlation analysis of two HRV tests on the same patient.

Results

There were 37 and 33 patients in the IDH and non-IDH groups, respectively. The HRV–IDH index predicted IDH occurrence with AUROCs of 0.776 and 0.803 for patients who had experienced at least one or repeated IDH episodes, respectively. Spearman's correlation coefficient for HRV–IDH indices was 0.859 for the first and second HRV tests.

Conclusions

The HRV test holds promise for predicting IDH, particularly for patients with recurring IDH diagnosed based on the nadir 90 criterion.
Artificial intelligence–powered insights into high-risk, non-obstructive coronary atherosclerosis: a case report
Authors: Provera Andrea , Andreini Daniele , Petersen Kersten , Gallinoro Emanuele , Conte Edoardo
Published: April 2024

Background

Advanced coronary plaque analysis by cardiac computed tomography (CT) has recently emerged as a promising technique for better prognostic stratification. However, this evaluation application in clinical practice is still uncertain.

Case summary

In the present case, we described the clinical picture of a 44-year-old tennis player with ectopic ventricular beats in which cardiac CT enabled the identification of a non-obstructive but high-risk plaque on proximal left anterior descendent artery. The application of artificial intelligence (AI)-enhanced software enabled to better stratify the patients’ risk. The present case describes how early identification of non-obstructive but high-risk coronary plaque evaluated by cardiac CT using AI-enhanced software enabled accurate and personalized risk assessment.

Discussion

The main clinical message of this case report is that advanced plaque analysis by cardiac CT, especially when performed with AI-based software, may provide important prognostic information leading to a personalized preventive approach. Moreover, AI-based software may contribute to promote a routine evaluation of these important data already included in traditional cardiac CT.
Progressive worsening of aortic regurgitation due to detachment of the aortic valve commissure with multimodality imaging to elucidate pathogenesis: a case report
Authors: Nishino Shun , Nishimura Masanori , Asada Yujiro , Yamashita Atsushi , Shibata Yoshisato
Published: April 2024

Background

Aortic regurgitation (AR) associated with detachment of the aortic valve commissure is extremely rare. We present a case of progressively worsening severe chronic AR due to detachment of the aortic valve commissure during hospitalization that was confirmed with multimodality imaging.

Case summary

A 50-year-old male with Marfan syndrome visited our hospital to receive treatment for cholelithiasis. Pre-operative examination revealed severe AR and aortic root aneurysm. Because the patient was asymptomatic, it was decided that cholecystectomy should be performed first. However, the patient’s heart failure worsened acutely when his blood pressure increased just before induction of anaesthesia. The patient required intubation and management of heart failure. Five days later, the patient underwent cholecystectomy. He was treated for heart failure and underwent open heart surgery on the 35th hospital day. Intraoperative transoesophageal echocardiography revealed that his AR was caused by both enlargement of the aortic root and localized dissection of the aortic valve commissure, which was supported by intraoperative findings and histopathological evaluation. Aortic regurgitation was exacerbated by a new localized dissection, resulting in acute worsening of heart failure.

Discussion

Aortic valve commissure detachment can easily lead to sudden onset of severe AR, deteriorating haemodynamics, and acute pulmonary oedema. Since delayed medical treatment leads to poor clinical outcomes, prompt and accurate diagnosis and appropriately timed surgical intervention are essential. This very rare case of severe AR worsening due to spontaneous aortic valve commissure dissection was evaluated with multiple modalities during hospitalization. Understanding this clinical condition will help cardiologists provide better medical care.
A preliminary study on the normal values of the thoracic Haller index in children
Authors: Song Wan-Yi , Zhou Yu , Wu Chun , Pan Zheng-Xia , Li Yong-Gang
Published: April 2024

OBJECTIVES

The Haller index (HI) is widely utilized as a quantitative indicator to assess the extent of the pectus excavatum (PE) deformity, which is the most common chest wall abnormality in children. Both preoperative correction planning and postoperative follow-up need to be based on the standard of normal thoracic growth and development. However, there is currently no established reference range for the HI in children. Consequently, the goal of this study was to conduct a preliminary investigation of normal HI values among children to understand thoracic developmental characteristics.

METHODS

Chest computed tomography images obtained from January 2012 to March 2022 were randomly selected from the imaging system of the Children's Hospital of Chongqing Medical University. We divided the images of children into a total of 19 groups: aged 0–3 months (1 group), 4–12 months (1 group) and 1 year to 17 years (17 groups), with 50 males and 50 females, totaling 100 children in each group. HI was measured in the plane where the lowest point of the anterior thoracic wall was located and statistically analysed using SPSS 26.0 software.

RESULTS

A total of 1900 patients were included in the study. Our results showed that HI, transverse diameter and anterior-posterior diameter were positively correlated with age (P < 0.05). Using age as the independent variable and HI as the dependent variable, the best-fit regression equations were HI-male = 2.047 * Age0.054(R2 = 0.276, P<0.0001) and HI-female = 2.045 * Age0.067(R2 = 0.398, P<0.0001). Males had significantly larger thoracic diameters than females, and there was little difference in the HI between the 2 sexes.

CONCLUSIONS

The HI rapidly increases during the neonatal period, slowly increases during infancy and stops increasing during puberty, with no significant differences between the sexes.
Transforming mineral capital into human capital? Mining and education in early twentieth-century Spain
Authors: Palacios-Mateo Adrian
Published: April 2024

Using a highly detailed dataset at the municipality level, drawn from the Spanish Mining Cadastre of 1890, this paper shows how the mining sector affected education provision and human capital formation in early twentieth century Spain. The results indicate that there were two patterns in mining towns. Those mines that invested in technology, those highly productive, and those with post-extraction industries linkages were able to transform mineral capital into human capital. However, in areas where mines were characterized by unskilled labour and low living standard, the mining sector had a negative impact on education, especially in women’s human capital formation.
Development and validation of a lifetime prediction model for incident type 2 diabetes in patients with established cardiovascular disease: the CVD2DM model
Authors: Helmink Marga A G , Peters Sanne A E , Westerink Jan , Harris Katie , Tillmann Taavi , Woodward Mark , van Sloten Thomas T , van der Meer Manon G , Teraa Martin , Dorresteijn Jannick A N , Ruigrok Ynte M , Visseren Frank L J , Hageman Steven H J ,   the UCC-SMART study group, Cramer M J , Nathoe H M , van der Meer M G , de Borst G J , Teraa M , Bots M L , van Smeden M , Emmelot-Vonk M H , de Jong P A , Lely A T , van der Kaaij N P , Kappelle L J , Ruigrok Y M , Verhaar M C , Dorresteijn J A N , Visseren F L J
Published: April 2024

Aims

Identifying patients with established cardiovascular disease (CVD) who are at high risk of type 2 diabetes (T2D) may allow for early interventions, reducing the development of T2D and associated morbidity. The aim of this study was to develop and externally validate the CVD2DM model to estimate the 10-year and lifetime risks of T2D in patients with established CVD.

Methods and results

Sex-specific, competing risk-adjusted Cox proportional hazard models were derived in 19 281 participants with established CVD and without diabetes at baseline from the UK Biobank. The core model’s pre-specified predictors were age, current smoking, family history of diabetes mellitus, body mass index, systolic blood pressure, fasting plasma glucose, and HDL cholesterol. The extended model also included HbA1c. The model was externally validated in 3481 patients from the UCC-SMART study. During a median follow-up of 12.2 years (interquartile interval 11.3–13.1), 1628 participants with established CVD were diagnosed with T2D in the UK Biobank. External validation c-statistics were 0.79 [95% confidence interval (CI) 0.76–0.82] for the core model and 0.81 (95% CI 0.78–0.84) for the extended model. Calibration plots showed agreement between predicted and observed 10-year risk of T2D.

Conclusion

The 10-year and lifetime risks of T2D can be estimated with the CVD2DM model in patients with established CVD, using readily available clinical predictors. The model would benefit from further validation across diverse ethnic groups to enhance its applicability. Informing patients about their T2D risk could motivate them further to adhere to a healthy lifestyle.
Application of a circular-shaped pulsed field ablation catheter with magnetic sensors for pulmonary vein isolation: a multi-centre clinical study report
Authors: Wang Yan , Lai Heng Li , Chen Qi , Liu Hao , Liu Qi Ming , Huang Wei Bin , Tao Yu , Xiong Qingmei , Zhou Ning , Zhao Chunxia , Qiu Jie , Xu Ziqin , Wang Dao Wen
Published: April 2024

Aims

A few studies have reported the effect and safety of pulsed field ablation (PFA) catheters for ablating atrial fibrillation (AF), which were mainly based on basket-shaped or flower-shaped designs. However, the clinical application of a circular-shaped multi-electrode catheter with magnetic sensors is very limited. To study the efficacy and safety of a PFA system in patients with paroxysmal AF using a circular-shaped multi-electrode catheter equipped with magnetic sensors for pulmonary vein isolation (PVI).

Methods and results

A novel proprietary bipolar PFA system was used for PVI, which utilized a circular-shaped multi-electrode catheter with magnetic sensors and allowed for three-dimensional model reconstruction, mapping, and ablation in one map. To evaluate the efficacy, efficiency, and safety of this PFA system, a prospective, multi-centre, single-armed, pre-market clinical study was performed. From July 2021 to December 2022, 151 patients with paroxysmal AF were included and underwent PVI. The study examined procedure time, immediate success rate, procedural success rate at 12 months, and relevant complications. In all 151 patients, all the pulmonary veins were acutely isolated using the studied system. Pulsed field ablation delivery was 78.4 ± 41.8 times and 31.3 ± 16.7 ms per patient. Skin-to-skin procedure time was 74.2 ± 29.8 min, and fluoroscopy time was 13.1 ± 7.6 min. The initial 11 (7.2%) cases underwent procedures with deep sedation anaesthesia, and the following cases underwent local anaesthesia. In the initial 11 cases, 4 cases (36.4%) presented transient vagal responses, and the rest were all successfully preventatively treated with atropine injection and rapid fluid infusion. No severe complications were found during or after the procedure. During follow-up, 3 cases experienced atrial flutter, and 11 cases had AF recurrence. The estimated 12-month Kaplan–Meier of freedom from arrhythmia was 88.4%.

Conclusion

The PFA system, comprised of a circular PFA catheter with magnetic sensors, could rapidly achieve PVI under three-dimensional guidance and demonstrated excellent safety with comparable effects.