bluuebunny/crossref_metadata_2025 huggingface dataset:
An NMOS output-capacitorless low-dropout regulator with dynamic-strength event-driven charge pump
Authors: Xie Yiling , Wang Baochuang , Chen Dihu , Guo Jianping
Published: June 2024

In this paper, an NMOS output-capacitorless low-dropout regulator (OCL-LDO) featuring dual-loop regulation has been proposed, achieving fast transient response with low power consumption. An event-driven charge pump (CP) loop with the dynamic strength control (DSC), is proposed in this paper, which overcomes trade-offs inherent in conventional structures. The presented design addresses and resolves the large signal stability issue, which has been previously overlooked in the event-driven charge pump structure. This breakthrough allows for the full exploitation of the charge-pump structure's potential, particularly in enhancing transient recovery. Moreover, a dynamic error amplifier is utilized to attain precise regulation of the steady-state output voltage, leading to favorable static characteristics. A prototype chip has been fabricated in 65 nm CMOS technology. The measurement results show that the proposed OCL-LDO achieves a 410 nA low quiescent current (I
Q) and can recover within 30 ns under 200 mA/10 ns loading change.
A 28/56 Gb/s NRZ/PAM-4 dual-mode transceiver with 1/4 rate reconfigurable 4-tap FFE and half-rate slicer in a 28-nm CMOS
Authors: He Yukun , Yuan Zhao , Wang Kanan , Tang Renjie , He Yunxiang , Chen Xian , Ye Zhengyang , Gui Xiaoyan
Published: June 2024

A 28/56 Gb/s NRZ/PAM-4 dual-mode transceiver (TRx) designed in a 28-nm complementary metal-oxide-semiconductor (CMOS) process is presented in this article. A voltage-mode (VM) driver featuring a 4-tap reconfigurable feed-forward equalizer (FFE) is employed in the quarter-rate transmitter (TX). The half-rate receiver (RX) incorporates a continuous-time linear equalizer (CTLE), a 3-stage high-speed slicer with multi-clock-phase sampling, and a clock and data recovery (CDR). The experimental results show that the TRx operates at a maximum speed of 56 Gb/s with chip-on board (COB) assembly. The 28 Gb/s NRZ eye diagram shows a far-end vertical eye opening of 210 mV with an output amplitude of 351 mV single-ended and the 56 Gb/s PAM-4 eye diagram exhibits far-end eye opening of 33 mV (upper-eye), 31 mV (mid-eye), and 28 mV (lower-eye) with an output amplitude of 353 mV single-ended. The recovered 14 GHz clock from the RX exhibits random jitter (RJ) of 469 fs and deterministic jitter (DJ) of 8.76 ps. The 875 Mb/s de-multiplexed data features 593 ps horizontal eye opening with 32.02 ps RJ, at bit-error rate (BER) of 10−5 (0.53 UI). The power dissipation of TX and RX are 125 and 181.4 mW, respectively, from a 0.9-V supply.
Leveraging an Asymmetric Convolutional Neural Network for Power System Object Intelligent Recognition
Authors: Zhou Yi , Liu Siyao , Wang Ningguo , Zhao Zhongying
Published: June 2024

In the realm of automatic inspection within the power system industry, leveraging artificial intelligence algorithms for the automated detection of typical objects holds immense significance. This paper introduces a novel approach, an asymmetric convolutional neural network, designed for intelligent recognition of typical objects in the power system. Specifically, the proposed algorithm adopts the YOLOv7 network architecture as a baseline for object detection, incorporating a newly developed asymmetric convolution layer. This innovative layer aims to enhance the extraction of image features and improve robustness against target flipping. The effectiveness of the proposed method was validated through its application to a project at the Information & Telecommunication Company, State Grid Ningxia Electric Power Co., Ltd. The objective was to detect the presence of the person in charge at the operation scene. Experimental results demonstrated a notable improvement, with the detection mAP of the person in charge reaching 95.8%, a 6.9% increase compared to YOLOv7, effectively enhancing accuracy. Additionally, the model achieved a recall rate of 93.4%, making it applicable for power system operation detection tasks and elevating the industry’s level of automation.
NASNet-LSTM based Deep learning Classifier for Anomaly Detection in Solar Photovoltaic Modules
Authors: Gopalakrishnan Shiva , Wahab Noor Izzri Abdul , Veerasamy Veerapandiyan , Hizam Hashim , Farade Rizwan A
Published: June 2024

Many nations are increasing the installations of solar photovoltaic (PV) modules for clean energy production. Such PV modules are considered to be cost effective if the module’s operation lifetime is more than twenty years. In real-time, the PV modules undergo degradation due to hotspots, defects and other anomalies resulting in reduced operation lifetime. Infrared (IR) Thermography is a Non-Destructive Testing (NDT) method that can be used in identifying such anomalies present in PV modules. However, the IR thermography requires Artificial Intelligence (AI) based classification techniques to detect the anomalies. This research article proposes a deep learning classifier, based on NASNet-LSTM for the identification of electrical and non-electrical anomalies occurring in PV modules. NASNet is a convolutional neural network (CNN) based classifier when combined with Long Short-Term Memory (LSTM) Networks performs classification with an accuracy of 84.75% considering the raw dataset used in this research. The results are validated by comparing the accuracies with other models. The study concludes that NASNet-LSTM performs well in the anomaly detection of PV modules.
Electric Vehicles and Renewable Energy
Authors: Aydogan Hasan
Published: June 2024

This paper explores the synergistic relationship between electric vehicles and renewable energy sources in addressing environmental concerns and fostering sustainable transportation. While electric vehicles offer the significant benefit of zero tailpipe emissions, their environmental impact hinges on the source of their electricity. The paper highlights the crucial role of renewable energy sources like solar, wind, and hydropower in powering electric vehicles and minimizing their carbon footprint. Examining various charging methods, including home solar systems, public charging stations with renewables, and smart charging systems, the paper demonstrates the feasibility and practicality of integrating EVs with renewable energy. The advantages of electric vehicles over gasoline vehicles are then presented, emphasizing their lower maintenance needs, cost-effectiveness, quieter operation, energy efficiency, and positive impact on air quality. Finally, the paper underscores the potential of electric vehicles to promote the transition towards a more sustainable and environmentally friendly energy landscape.
Research on abnormal diagnosis model of electric power measurement based on small sample learning
Authors: Zhuang Gewei , Gu Zhen , Qing He , Zhang Jingyue , Zhang Honghong , Zhou Lei
Published: June 2024

For a long time, abnormal metering of electricity meters has caused huge economic losses to power grid companies. Abnormal diagnosis of power metering is an important means to ensure the normal operation of electricity meters and power automation operation and maintenance systems and is a hot topic of research for power workers. This article proposes a known measurement anomaly diagnosis model based on small sample learning to address the problem of insufficient labeled samples in power measurement anomaly diagnosis. The embedded network maps samples from the original sample space to the embedded space adjusts the embedded network structure, and improves the loss function. The experimental results show that the improved classification network has a higher recognition accuracy for known anomalies than the original network and other small sample learning models.
Optimization of demand side management strategies for building clusters based on cooperative game theory
Authors: Xu Jinyi , Wang Yongtao , Ding Jianzhong , He Kai
Published: June 2024

In recent years, with the increasing difficulty of real-time supply-demand balance in the power system, the importance of system optimization scheduling has become increasingly prominent. By flexibly adjusting the elastic load on the power demand side, new ideas have been provided to alleviate the supply-demand contradiction in the power system. However, most existing demand-side management strategies use nonlinear optimization algorithms, which not only have complex optimization processes but also often overlook the ability of different energy flexibility systems to coordinate and cooperate when dealing with a large number of buildings connected to the grid. There is still significant room for improvement in the efficiency of control measures and the accuracy of results. This article proposes two optimization operation schemes for EFB clusters based on cooperative games, namely “system sharing” and “microgrid interconnection”. Among them, for the system sharing scheme, this article establishes an optimization control algorithm based on an alliance game, quantitatively analyzes the real-time contribution of each participant in the construction alliance, and determines the corresponding hourly control strategy based on this. For the microgrid interconnection scheme, this article adopts a bargaining game model to determine the control logic and related profit distribution principles of energy consumption interconnection within the building cluster. We simulate the game model by using MATLAB software, and the result shows that the system sharing mode can reduce the comprehensive electricity cost and peak valley energy consumption difference of the building cluster by 6.9%∼13.0% and 3.1%∼6.7%, respectively, which has a significant improvement effect on the problem of power grid supply-demand imbalance. Although the microgrid interconnection mode cannot change the peak and valley energy consumption of buildings, it can significantly improve the economic efficiency of building clusters and reduce the comprehensive electricity cost by 11.8% to 17.3%.
Autonomous operation domain generation and reduction method supporting the seamless power supply of important loads
Authors: Zhou Jinhui , Wang Ke , Ge Jiabei , Xu Xu , Wu Hongmin
Published: June 2024

In order to fully and accurately perceive the security risks of the intelligent distribution network, an autonomous operation domain generation and reduction method to support the seamless power supply of important loads is proposed. This method first adopts the scenario analysis method to analyze the photovoltaic uncertainty, introduces the micro-phasor measurement units (µPMU) with real-time, synchronization, accuracy, and comprehensive measurement data, and builds the fault data set through the scenario of each fault type occurring in each node of the smart distribution network. By constructing the load loss risk index of the autonomous operation domain under the photovoltaic scenario and the seamless switching ability index under the fault state, the autonomous operation domain evaluation and screening method based on the Dynamic Time Warping (DTW) algorithm is proposed. Combined with the evaluation index system, the autonomous operation domain scenario under the fault state is evaluated. The simulation results prove that this method is enough to realize the reliable screening of the autonomous operation domain scene set in the fault state, and effectively support the seamless power supply of important loads and the seamless operation of the distribution network.
Ultra-short-term dynamic prediction of multiple types of energy sources based on two-stage transfer learning
Authors: Wang Yuxin , Du Jiao , Zhang Haichuan
Published: June 2024

In this thesis, starting from the source load of the integrated energy system, the source load in the park is analyzed for the energy side of wind turbine power generation, hot and cold energy, photovoltaics, as well as for the related electric and hot and cold load side of enterprises and buildings. The ultra-short-term time-scale load prediction is performed based on artificial intelligence algorithms, respectively. The time series prediction model is trained by three factors, namely temperature, season, and holidays, using the data of electric load, heat load, and cold load to obtain the primary model. Based on the primary model, the final prediction model is obtained by adopting the migration learning strategy.
Microwave characterization of nanomaterials using planar slot resonator
Authors: Dhanasekaran Aravinth , Sumithra P. , Kommuri Usha Kiran , Kannadassan D. , Velmurugan V.
Published: June 2024

Nanomaterial characterization using microwaves is needed in nanoscale
semiconductor devices, microwave imaging, EM shielding, and wireless
communication. Many nanomaterials are used as metallic or dielectric
layers in these applications. In this paper, we report the characterization
of nanomaterials using planar Microwave Slot Resonator (MSR) which
was designed and studied using 3D EM simulation tool. The response
of MSR is parameterized which offers a platform to calculate relative
permittivity (ε
r) and conductivity (σ) from
measured high frequency response of nanomaterial loaded MSR. With
simplified method, this microwave characterization offers accurate
and faster results which be used in design, calculation and numerical
analysis of nanomaterial based electronic/optoelectronic devices and
sensor/shielding applications.
Wall-climbing performance of gecko-inspired robot with soft feet and digits enhanced by gravity compensation
Authors: Wang Bingcheng , Weng Zhiyuan , Wang Haoyu , Wang Shuangjie , Wang Zhouyi , Dai Zhendong , Jusufi Ardian
Published: June 2024

Gravitational forces can induce deviations in body posture from desired configurations in multi-legged arboreal robot locomotion with low leg stiffness, affecting the contact angle between the swing leg’s end-effector and the climbing surface during the gait cycle. The relationship between desired and actual foot positions is investigated here in a leg-stiffness-enhanced model under external forces, focusing on the challenge of unreliable end-effector attachment on climbing surfaces in such robots. Inspired by the difference in ceiling attachment postures of dead and living geckos, feedforward compensation of the stance phase legs is the key to solving this problem. A feedforward gravity compensation (FGC) strategy, complemented by leg coordination, is proposed to correct gravity-influenced body posture and improve adhesion stability by reducing body inclination. The efficacy of this strategy is validated using a quadrupedal climbing robot, EF-I, as the experimental platform. Experimental validation on an inverted surface (ceiling walking) highlights the benefits of the FGC strategy, demonstrating its role in enhancing stability and ensuring reliable end-effector attachment without external assistance. In the experiment, robots without FGC only completed 3 out of 10 trials, while robots with FGC achieved a 100% success rate in the same trials. The speed was substantially greater with FGC, achieving 9.2 mm s−1 in the trot gait. This underscores the proposed potential of the FGC strategy in overcoming the challenges associated with inconsistent end-effector attachment in robots with low leg stiffness, thereby facilitating stable locomotion even at an inverted body attitude.
Fewer tropical cyclones yield more near-inertial wind work to the global ocean over the past four decades
Authors: Ma Yonggui , Shu Yeqiang , Wang Dongxiao , Hu Zhan , Li Mingting , Song Wei
Published: June 2024

In general, tropical cyclones (TCs) will inject energy into oceanic inertial motion‒a prevalent phenomenon in the ocean. Under global warming, the intensity of TCs is on the rise, while their frequency has exhibited a decline since 2000. However, the long-term trend of this energy infusion is an underexplored problem in this context. Using a damped-slab model, we computed the wind work exerted by TCs on the ocean’s mixed-layer inertial motions. Our results show that the global wind work has increased by approximately 50% from 1979 to 2023. The wind work increase of strong TCs (Saffir–Simpson levels 4–5) is the major contributor to the increasing trend of global wind work, primarily due to their increasing frequency and substantial wind stress. At basin scale, the wind work input of the North Atlantic TCs has increased by 2 times, owing to an increase in both their intensity and frequency. Specifically, in the South Indian and the eastern North Pacific basins, the rise in wind work is primarily attributed to the enhanced wind energy of TCs within the inertial bands.
Chemical Dynamics in Condensed Phases
Authors: Nitzan Abraham
Published: June 2024

This second edition builds on the first, providing a uniform approach to diverse problems encountered in the study of dynamical processes in condensed-phase molecular systems. It focuses on three themes: coverage of needed background material, in-depth introduction of methodologies, and analysis of several key applications to processes of importance in physical, chemical and biological phenomena in complex systems. Chapter 1 starts with a general review of basic mathematical and physical methods. It is followed by a few introductory chapters on quantum dynamics (Chapter 2), radiation–matter interaction (Chapter 3) and introduction to solids (Chapter 4) and liquids (Chapter 5). Chapters 6–12 provide a broad coverage of the main methodological approaches: time-correlation functions (Chapter 6), stochastic processes (Chapters 7 and 8), quantum relaxation phenomena (Chapters 9 and 10), linear response theory (Chapter 11) and various forms of the spin–boson model for describing molecular interaction with the radiation field and the thermal environment (Chapter 12). Chapters 13–19 describe some key applications: Vibrational relaxation and vibrational energy transfer (Chapter 13), Barrier crossing and diffusion-controlled reactions (Chapter 14), solvation dynamics (Chapter 15), electron transfer in bulk solvents (Chapter 16) and at electrodes/electrolyte and metal/molecule/metal junctions (Chapter 17), and several processes pertaining to molecular spectroscopy in condensed phases (Chapter 18) and at dielectric interfaces (new Chapter 19).
The spin–boson model
Authors: Nitzan Abraham
Published: June 2024

This chapter discusses quantum relaxation within a generic model—the spin–boson model. (1) Introduction. (2) The spin–boson model. (3) The polaron transformation (the Born–Oppenheimer picture). (4) Golden-rule transition rates (the decay of an initially prepared level, the thermally averaged rate, evaluation of rates). (5) Transition between molecular and electronic states (the optical absorption lineshape, electronic relaxation of excited molecules, the weak coupling limit and the energy gap law, the thermal activation/potential-crossing limit). (6) Short-time approximation for the strong coupling limit. (7) Beyond the golden rule. (8) Spin-lattice relaxation.
Chemical reactions in condensed phases
Authors: Nitzan Abraham
Published: June 2024

The application of classical and quantum relaxation theory to the kinetics of chemical reactions in condensed phases is discussed in this chapter. (1) Unimolecular reactions. (2) Transition state theory (TST) (the underlying assumptions of transition state theory, transition state rate of escape from a one dimensional well, TST in a multidimensional system, TST for non-adiabatic transitions, TST with tunneling). (3) Dynamical effects in barrier crossing—the Kramers model (Escape from a one-dimensional well, the overdamped case, moderate-to-large damping, the low damping limit, implications and shortcomings of the Kramers theory, non-Markovian effects, the normal mode description of barrier crossing). (4) Some experimental observations. (5) Numerical simulation of barrier crossing. (6) Diffusion-controlled reactions.
Electron transfer processes
Authors: Abraham Nitzan
Published: June 2024

Electron transfer is one of the most important processes characterizing the dynamics of many chemical processes. This chapter describes the foundations of electron-transfer theory and its manifestation in experimental observations. (1) A primitive model for electron transfer. (2) Continuum dielectric theory of electron transfer (equilibrium electrostatics, transition assisted by dielectric fluctuations, thermodynamics with restrictions, dielectric fluctuations, reorganization energy, energetics of electron transfer between two ionic centers, the electron transfer rate). (3) A molecular theory of the non-adiabatic electron transfer rate. (4) Comparison with experimental results. (5) Solvent-controlled electron transfer dynamics. (6) A general expression for the dielectric reorganization energy. (7) The physical origin of the Marcus parabolas. (8) Harmonic field representation of dielectric response. (9) The non-adiabatic coupling and the Mulliken–Hush formula. (10) The distance dependence of electron transfer rates. (11) Bridge-mediated long-range electron transfer. (12) Electron transfer by hopping. (13) Proton transfer.
Depth-resolved potentiometric detection of active species near the surface of an aqueous solution under atmospheric pressure plasma
Authors: Kubota Kai , Yokoyama Yuko , Nishi Naoya , Sakka Tetsuo
Published: June 2024

Near the plasma/water interface, highly active species such as ·OH are formed, providing unique reaction fields. To develop interfacial reaction systems that utilize them, it is important to conduct in-situ quantitative analysis of their supply and consumption kinetics. In this study, depth- and time-resolved in-situ potentiometric measurements were performed to detect redox-active species, such as OH radicals. A Pt electrode was employed as an indicator electrode and showed a large potential shift to 1.5 V vs SHE only when the depth was less than 10 µm, suggesting the presence of ·OH.
Simultaneous Detection Method of 11 Respiratory Drug Substances Including Theobromine, Oxymetazoline, etc. in Adulterated Dietary Supplements Using Liquid Chromatography–Electrospray Ionization–Tandem Mass Spectrometry and Liquid Chromatography–Quadrupole Time-of-Flight Mass Spectrometry Analysis
Authors: Kim Mi Jin , Choi Hwan Seong , Shin Hyunil , Lee Ji Hyun , Kim Nam Sook , Kim Hyungil
Published: June 2024

Recently, the demand for respiratory disease-related products has surged due to the influence of coronavirus disease 2019, prompting warnings about illegal dietary supplements containing unauthorized substances. Additionally, adulterated dietary supplements are continuously detected in open markets, posing significant public health safety problem. In this study, we developed and validated an analytical method for 11 respiratory drug substances using liquid chromatography–electrospray ionization–tandem mass spectrometry (LC–ESI–MS/MS) and proposed optimal conditions for LC–quadrupole time-of-flight MS (LC–QTOF-MS) to determine the fragmentation patterns of each substance. This method underwent thorough validation considering specificity, linearity, limits of detection and quantification, accuracy, precision, matrix effect, stability, etc. All results met international guidelines. These validated methods were applied to 52 dietary supplements advertised for treating respiratory diseases and enhancing respiratory function, among which one sample was found to contain 313.7 mg/g of theobromine. This determination was made by comparing the product ion ratios with the standards and subsequent quantification. To re-confirm the detected substances, their fragmentation patterns were compared with those of the standards using LC–QTOF-MS. In conclusion, the mass-based information, coupled with the LC–ESI–MS/MS method development, can be successfully applied to rapidly identify 11 respiratory drug substances in illegal dietary supplements used for respiratory disease treatment. The developed simultaneous detection method contributes to public health and safety improvements.
The Medieval Public Sphere and the Response to a Condemnation for Heresy in Bologna, 1299
Authors: Barucci Teresa
Published: June 2024

Bologna, 1299. The purse-makers Bompietro and Giuliano are burned at the stake as heretics by the Dominican Inquisition. A discussion about the lack of fairness of the condemnation ensues and spreads all over the city. The outrage of the Bolognese community is such that an investigation into the disorders and a mass excommunication follow. This article uses the Bolognese episode, for which a rich documentation survives in the form of inquisitorial records, as a lens through which to observe and comment on the phenomenon of the ‘public sphere’ (a term coined in Habermas’s Strukturwandel der Öffentlichkeit) in medieval Europe. The first aim of the article is to demonstrate that it is possible to reconstruct a ‘public sphere’ in the specific context of the public response to the condemnation for heresy of the two purse-makers. In so doing, the article looks at the social composition and at the communication mechanisms of, and at the discussion taking place within, the Bolognese public sphere. Importantly, it proposes the idea that the Inquisition too was a public authority around which a public sphere could develop, in contrast to the focus on secular political institutions of the previous historiography. The second aim is to build on the evidence presented to demonstrate that the notion of the ‘public sphere’ can be an effective tool for the study of the interaction between the people and public authorities in the pre-modern world—if the critical functions rather than the structural characteristics of the phenomenon are emphasised.
Optimizing support before and after cardiac resynchronization therapy implantation in co-creation with patients with heart failure, informal caregivers, and healthcare professionals
Authors: Westland Heleen , van Rijn Michelle , Meine Mathias , Jaarsma Tiny
Published: June 2024

Aims

To optimize support by healthcare professionals to enhance physical activity, HF-related symptom monitoring, and management in patients with heart failure before and after cardiac resynchronization therapy (CRT) implantation in co-creation with patients, informal caregivers, and healthcare professionals.

Methods and results

A qualitative and co-design approach was used to develop support strategies collaboratively with end-users. Seventeen semi-structured interviews were conducted to explore patients’ expectations and factors influencing physical activity and symptom management. The qualitatively obtained insights informed the development of support strategies using an ideas group with patients, informal caregivers, and healthcare professionals.

Four themes emerged from the interviews: (1) expecting and hoping to regain energy and fitness; (2) difficulties and opportunities to become more active; (3) impact of CRT on sense of safety; and (4) dealing with continuing bothersome symptoms. Several strategies were brainstormed, prioritized, and prototyped, including optimization of CRT information, a peer contact list, expansion of the post-CRT implantation consultation to ask questions and share concerns, and a group meeting with peer patients, partners, and healthcare professionals.

Conclusion

Patients expected and hoped to have positive effects from CRT, but not all patients experienced improvement after CRT. To improve patients’ physical activity, feelings of insecurity, symptom monitoring, and thoughtful response to symptoms, support must include providing information and support to increase their knowledge and discuss experiences and physical and mental concerns.
Risk-factor dependant regulation of the miR-483-3p in metabolic HFpEF and pre-diabetes
Authors: Swaminathan K , Otvos J , Paolo F , Kirchhoff M , Kabisch S , Alogna A , Kraenkel N
Published: June 2024

Background

Prediabetes and the metabolic phenotype of heart failure with preserved ejection fraction (HFpEF) are two related diseases with high metabolic predisposition and prevalence. We previously described an increase in the micro-RNA miR-483-3p in M2-type macrophages and in endothelial cells in human patients with type 2 diabetes mellitus (T2DM) associated with reduced endothelial regenerative capacity. The miR-483-3p may also be relevant in metabolic HFpEF, but individual cardio-metabolic risk factors causing the upregulation of miR-483-3p have not been specified.

Purpose

We aimed to understand the relevance of the miR-483-3p in metabolic HFpEF and to identify the cardiovascular risk factors causing miR-483-3p upregulation in humans and in a large animal model of metabolic HFpEF.

Methods

M2-type macrophages were cultured from blood samples of healthy donors, individuals with prediabetes and patients with established T2DM (n=51, 63% female, age 41-75 years). Expression of hsa-miR-483-3p and hsa-miR-21-5p (housekeeping control) were determined by reverse transcription quantitative real time polymerase chain reaction (RT-qPCR) and correlated with donor characteristics (age at inclusion, biological sex, systolic and diastolic blood pressure, glycated haemoglobin (HbA1C), fasting glucose, fasting triglycerides (TG), high- and low-density lipoproteins, waist circumference). Cultured human aortic endothelial cells (EC) and M2-type primary macrophages were exposed to the fatty acid palmitate, bacterial lipopolysaccharides (LPS), tumour necrosis factor alpha (TNF-α) for 24 h prior to analysis of expression of the miR-483-3p.

Results

M2 macrophages of individuals with fasting plasma TG levels above 170mg/dL expressed more miR-483-3p (2.0±0.4-fold versus individuals below 170mg/dL TG, p=0.04). Consistently, miR-483-3p was upregulated in M2 macrophages and ECs by palmitic acid (M2: 13.5±7.1-fold versus control; EC: 1.7±0.3-fold versus control, p=0.01). In a porcine model of metabolic HFpEF, the miR-483-3p increased steadily over the initial 12 weeks of high sucrose/high cholesterol diet and subcutaneous deoxycorticosterone acetate application, maintaining a plateau for the following 2 months (57-fold to 300-fold of baseline, n=3). Higher cellular expression of the miR-483-3p in response to TNF-α (M2: 35.5±16.2-fold versus control, p=0.001; EC: 2.2±0.7-fold versus control, p=0.01) and LPS (M2: 31.1±13.4-fold versus control, p=0.005; EC: 1.7±0.4-fold versus control, p=0.01) indicate a potential role of inflammation.

Conclusion

The miR-483-3p is upregulated in individuals of the human pre-diabetic continuum, associated with triglyceride/fatty acid levels, as well as in a porcine model of metabolic HFpEF. Future studies need to evaluate whether miR-483-3p is a treatable target for maintaining endothelial function under pro-inflammatory and dyslipidaemic conditions in human patients at risk to develop HFpEF and T2DM.
Advantages of timely diagnosis of cardiac myxoma
Authors: Svanidze T , Saralidze T , Papuashvili K , Noniashvili M , Mamatsashvili I , Jgarkava M
Published: June 2024

Cardiac myxomas (M) are the most common benign primary tumor of the heart. They are biologically benign, but "functionally malignant" because of the potential for embolization. They arise most commonly from the left atrium, but it can involve any of the cardiac chambers.

Our purpose was to study patients with M.

Among 3150 patients, examined by us during last 3 years by Transthoracic echocardiography (TTE), we observed 7 cases of M. All patients were women, one 91 old, others - at the age of 62-75 years old. All of them had atrial M. One was right atrial M, and 6 –left atrial M.One case involves a 91- year-old female, who appeared in clinic due to severe COVID-19 infection. She presented with fatigue, fever of unknown origin, transient ischemic attack and shortness of breath. ECG showed sinus rhythm, P-78’, without signs of acute ischemia. In this case left atrial M represented a mass of 30×60 mm attached to the upper part of intra-atrial septum causing mitral valve obstruction (Fig.1). Patient had preserved ejection fraction (EF)-50% and diastolic dysfunction was observed due to pseudonormalisation. Normal size right ventricle, TAPSE-21mm, moderately dilated left atrium, fibrotic mitral valve leaflets and calcification of annulus with moderate regurgitation +2/+4, calcification of aortic valve with mild stenosis (Vmean-18mmHg, AVA-1.5cm²) and moderate regurgitation +2/+4 was also observed. Moderate pulmonary artery hypertension (pulmonary artery syst. pressure PASP - 55mmHg) was also revealed.

In the second case a patient with right atrial M was asymptomatic, she admitted clinic due to ischemic stroke. ECG was in normal range. TTE revealed moderate enlargement of right atrium and preserved EF - 53%. Diastolic dysfunction was presented by impaired relaxation. In the rest 5 cases patients applied to us with cardiologic problems. They had chronic heart failure (HF), NYHA class III, left atrial M, atrial fibrillation (AF) and arterial hypertension (AH). In all these cases the patients had moderate enlargement of both atria and right ventricle and moderate hypertrophy of left ventricle. EF was mildly reduced (46-48%).

All 7 patients were treated with rivaroxaban to prevent thromboembolic complications. In first two cases patients’ outcome was depended on the course and severity of the main disease and at this stage surgery was not applied. In 5 patients with AF, AH, HF and left atrial M was considered surgical intervention (Fig.2).

Our study showed that in some cases M has asymptomatic course, though it can cause thromboembolic complications. In other cases M depending on its size and location causes significant damage of heart mechanical and/ or electrical function. Thus routine TTE examination of patients in general practice is necessary. Timely diagnosis of cardiac M is important because these patients require long term anticoagulation treatment for the prevention of life-threatening complications. Fig.1; Fig.2. Left atrial myxoma
Increased incidence of arrhythmias, heart failure and thrombosis in COVID-19 patients after the first 3 months post-infection: a population-based cohort study
Authors: Degano I R , Tintore C , Camps-Vilaro A , Subirana I , Elosua R , Marrugat J
Published: June 2024

Background

Studies on long-term outcomes have shown that coronavirus disease 19 (COVID-19) survivors have a higher risk of cardiovascular disease (CVD) events at 1-year. However, most studies have analyzed outcomes at 1-year excluding or not the first 21-30 days, but there is no information for other follow-up periods.

Purpose

Our aim was to examine CVD outcomes during the first 3 months after infection/inclusion and from 4 to 12 months, in COVID-19 patients compared to individuals that did not had COVID-19, by sex.

Methods

Data were obtained from the Data analytics program for health research and innovation (PADRIS) from Catalonia, North-Eastern Spain. PADRIS includes data from the Catalan health system, covering 7.9 million inhabitants. Selected individuals were ≥45 years old with a positive COVID-19 PCR/antigen/rapid test in March-May 2020. We also included randomly selected individuals without a positive/suspicious COVID-19 test. Follow-up was obtained until January 31st, 2021 for CVD events (atrial fibrillation(AF)/flutter/tachycardia, bypass/revascularization, heart failure, peripheral artery disease, stroke/transient ischemic attack, and thrombosis), and until March 31st, 2021 for mortality. CVD event incidence was compared with Cox proportional hazards regression.

Results

We included 173,782 individuals, of those 30,831 had COVID-19. Median follow-up was 335 days for CVD outcomes and 392 days for mortality. Incidence of CVD outcomes and mortality had a large increase in COVID-19 individuals during the first 100 days of follow-up. In the whole follow-up, and in the first 3 months, having COVID-19 was associated with lower time to all CVD events and mortality in females and males (Figures 1 and 2). During the first 3 months, the CVD events with the highest risk increase were thrombosis in females and AF/flutter/tachycardia in males. In the period from 4 months to the end of the follow-up, there was an increased risk of heart failure in females (1.73 [1.23-2.43]). While in males, there was an increased risk of AF/flutter/tachycardia (1.61 [1.10-2.36]) and of thrombosis (2.85 [1.18-6.86]).

Conclusions

Our findings suggest that incidence of some CVD outcomes associated with COVID-19 may decrease after 3 months. However, control of arrhythmias, heart failure, and thrombosis could be necessary after this period depending on the sex. CVD outcome incidence in females  CVD outcome incidence in males
Reassessing the association between age at menarche and cardiovascular disease: observational and Mendelian randomisation analyses
Authors: Tschiderer L , Peters S A E , Van Der Schouw Y T , Seekircher L , Willeit P , Onland-Moret N C
Published: June 2024

Background

Observational studies have shown a non-linear U-shaped association between age at menarche and cardiovascular disease (CVD).

Purpose

The aim of this study was to reassess the observational association between age at menarche and CVD and investigate whether the causal relationship between age at menarche and CVD is non-linear.

Methods

We included women from the UK Biobank and EPIC-CVD study without a history of myocardial infarction or stroke at baseline. In observational analyses, we estimated study-specific hazard ratios (HRs) for myocardial infarction, ischaemic stroke, and haemorrhagic stroke using Cox-regression before meta-analysing them. In addition, we conducted non-linear Mendelian randomisation analyses based on fractional polynomials and performed linear Mendelian randomisation analyses using inverse-variance weighted regression.

Results

Our analyses included 283,210 women without a history of myocardial infarction or stroke at baseline, of which 8,468 had a myocardial infarction, 5,501 an ischaemic stroke, and 1,887 a haemorrhagic stroke. Mean age at menarche was 13.1 (SD 1.6) in the UK Biobank and 13.0 (SD 1.6) years in EPIC-CVD. The association between age at menarche and myocardial infarction and ischaemic stroke was U-shaped with higher risks in women aged <12 and ≥16 compared to those aged 13 years at menarche. We found no statistically significant association with haemorrhagic stroke. Our Mendelian randomisation analysis based on fractional polynomials suggested no non-linear relationship between genetically proxied age at menarche and any CVD endpoint, but each year higher genetically proxied age at menarche was statistically significantly related to a lower risk of myocardial infarction (HR 0.92 [95% CI 0.86-0.99]), but not to ischaemic (1.00 [0.91-1.09]) and haemorrhagic stroke (1.02 [0.89-1.17]).

Conclusion

In conclusion, although the observational association between age at menarche and myocardial infarction and ischaemic stroke was non-linear, our analysis revealed no indication of a non-linear relationship between higher genetically proxied age at menarche and risk of myocardial infarction, and there appeared to be no causal link with ischaemic and haemorrhagic stroke.
Lipoprotein (a): what role in long-termprognosis of patients with acute myocardial infarction
Authors: Quintal J , Coelho R A , Pohle C L , Ferreira J S , Bernardes P , Duarte T , Goncalves S , Seixo F
Published: June 2024

Background

Lipoprotein(a) is a known risk factor for atherosclerotic coronary heart disease. This genetically regulated protein is constant throughout the individual lifetime and therefore a single measurement may estimate the individual risk of coronary artery disease (CAD). Nonetheless, its impact on long-term prognosis of patients (pts) with acute myocardial infarction (AMI) is not well stablished.

Aim

To assess whether lipoprotein(a) (Lpa) level can predict long-term prognosis of pts hospitalized for acute myocardial infarction, based on all-cause mortality, readmission due to acute coronary syndrome (ACS) and readmission due to major cardiovascular disease(CVD).

Methods

We performed a single-center retrospective cohort study. Consecutive pts admitted in our center between 1 November 2021 and 31 October 2022 with ACS were included (n=390). Patient without Lpa measurement at admission were excluded (n=62). Patients were divided in 2 groups according to Lpa level upon hospital admission: gA - normal Lpa level (Lpa < 30mg/dL) - and gB– high Lpalevel (Lpa≥ 30mg/dL). Cardiovascular risk factorsand relevant comorbidities were assessed in both groups.

The type ofACS, the number of affected coronary arteries, left ventricle ejection fraction (LVEF), Kilipp Kimball (KK)class, the presence of significant arrhythmias, high-sensitivity troponin (hs-TnI) and NT-proBNP levels were evaluated in both groups. Long term prognosis analysis included long-term all cause mortality, hospital readmission due to ACS and hospital readmission due to major CVD.

Results

The study included 328 pts, with a mean age of 66 (± 12) years-old and a 71.6% male prevalence. Regarding baseline characteristics of individuals, gB had a higher prevalence of dyslipidemia (31.3%vs 28.9, p=0.015), chronic kidney disease (11.6 vs 5%, p=0.029) and CAD(32.7 vs 22.9%, p=0.049).

There were no significant differences inACS type, LVEF, KK class, hs-TnI and NT-proBNP levels. Group B had a higher prevalence of 3 vessel disease(26.9 vs 17.6%, p=0.045) while 1 vessel disease was more common in gA (48.9 vs 37.9%, p=0.05). There was a higher tendency for arrythmias within 48h of ACS in gA (22.2 vs 13.6%, p=0.045).

In-hospital mortality was similar between the groups (gA3.9 vs gB3.4%, p=0.816). During a median follow-up time of 18 (0-25) months, 27 deaths were verified. Mortality was not statistically different between the groups (gA 10.6 vs gB 6.5%, p= 0.816). Readmissions duetoACS(gA2.3 vs gB6.4%, p=0.073)and CVD (gA9.9 vs gB12.2%, p=0.477) were also similar in both groups.

Conclusions

This study suggests that, although lipoprotein(a) is a well-known risk factor for CAD development, a single measurement above the cut-off of 30mg/dL may not be associated with a poorer long-term cardiovascular prognosis in pts with AMI. Further studies are needed to provide robust data and reliable recommendations on this theme.
The long-term prognosis of unrecognized myocardial infarction in women and men from the general population
Authors: Van Oortmerssen J A E , Tilly M J , Ikram M K , Boersma E , Roeters Van Lennep J E , Kavousi M
Published: June 2024

Background

Unrecognised myocardial infarction (MI) is a subclinical MI that escapes detection during its acute phase and is associated with an adverse prognosis, similar to clinically recognized MI. Previous studies have suggested the unfavourable outlook for men, and to a lesser extend in women. However, thorough investigation regarding sex differences in prognosis of unrecognised MI for various major adverse outcomes is limited.

Purpose

This study sought to assess sex differences in the long-term prognosis of unrecognised MI with respect to subsequent clinically recognised MI, heart failure, atrial fibrillation, stroke and all-cause mortality.

Methods

In a population-based cohort study, encompassing three cohorts with extensive follow-up time, MI status was established at baseline by electrocardiography (ECG) and data from medical records. Participants were followed for the outcomes of interest and censored at the incidence date, loss to follow-up, death, or to 1 January 2015, whichever occurred first. Additionally, participants in the unrecognised MI group were censored once recognised MI occurred. Per outcome of interest, multivariable Cox proportional hazards regression analyses were performed to calculate hazard ratios (HR) and corresponding 95% confidence intervals (CI), using participants without MI at baseline as reference group. All analyses were stratified for sex.

Results

Of the 12,409 participants at baseline, 519 (4.2%) had experienced unrecognised MI (mean age 70 years, 52% women) and 678 (5.5%) recognised MI (mean age 69 years, 28% women). Mean follow-up time was 10.2 years (± 7.9). Unrecognised MI showed a similar association with subsequent recognised MI in women and men (women; HR 1.57 [95% CI 1.05-2.35], men; HR 1.55 [95% CI 1.10-2.18]). In contrast, associations of unrecognised MI with heart failure (women; HR 1.03 [95% CI 0.77-1.39], men; HR 1.59 [95% CI 1.17-2.15]), atrial fibrillation (women; HR 0.89 [95% CI 0.64-1.25], men; HR 1.83 [95% CI 1.35-2.48]), stroke (women; HR 1.21 [95% CI 0.89-1.64], men; HR 1.87 [95% CI 1.35-2.59]) and all-cause mortality (women; HR 1.09 [95% CI 0.94-1.27], men; HR 1.37 [95% CI 1.16-1.62]) were statistically significant solely in men.

Conclusions

Unrecognised MI determined by ECG is associated with an increased risk of subsequent recognised MI in both sexes. Additionally, in men, it is associated with an increased risk of heart failure, atrial fibrillation, stroke, and all-cause mortality. Future research should prioritize accurate MI diagnosis via ECG and identify key predictors for adverse outcomes, aiding targeted management efforts.
ACS Program. Improving secondary prevention in patients admitted due to a myocardial infarction. First year experience
Authors: Gual M , Valverde J , Santalo M , Ferrer M , Gonzalez Freixa C , Sionis A
Published: June 2024

Background

Ischaemic heart disease is one of the leading causes of mortality in developed countries. Despite great advances in treatment and preventive measures in patients with myocardial infarction, cardiovascular risk still persists, with rates of new cardiovascular events being up to 10% in the first 12 months and even 20% in the first 5 years after the first admission. Stablishing standardized follow-up pathways in patients discharged to home and starting secondary prevention measures with special emphasis in targeting dyslipidemia is of main importance.

Purpose

The ACS Program was born with the aim to reorganize the outpatient Clinic Follow-up of patients with myocardial infarction in our area. With this aim, a structured pathway has been stablished (scheduled appointments with a cardiovascular specialized nurse and doctor and lab tests in the first 3, 6 and 12 months).

Methods

Descriptive study of all patients admitted to ACS Program since November 2022 to September 2023.

Results

170 patients have been admitted to the Program. Mean age is 62 years (SD 10 years). 70% of patients are male. The Average time since the patient is discharged to home until the first visit is 8,4 days (SD 5 days). More than a half of patients undergo a lab test in the first quarter (85%). 54% of patients achieve LDLc levels <55mg/dl in the first quarter. Moreover, 84% of patients achieve cLDL levels below 70mg/dl in the first three months. 30 and 90 day readmission rates are 3.7% and 7.4%, respectively. Mortality rates were low (0.3%, mean follow up 6 months), if we compare with global mortality rates of ichaemic heart disease in our centre (10%) (p<0,05). Finally, high intensity statins and ezetimbe prescription have increased since the Program began (80% versus 30%, p < 0.05).

Conclusions

Stablishing an organized follow-up pathway in patients discharged to home after a myocardial infarction permits achieving better cLDL control with low readmission rates and little time to first medical contact