bluuebunny/crossref_metadata_2025 huggingface dataset:
Principal role of fungi in soil carbon stabilization during early pedogenesis in the high Arctic
Authors: Trejos-Espeleta Juan Carlos , Marin-Jaramillo Juan P. , Schmidt Steven K. , Sommers Pacifica , Bradley James A. , Orsi William D.
Published: July 2024

Climate warming is causing widespread deglaciation and pioneer soil formation over glacial deposits. Melting glaciers expose rocky terrain and glacial till sediment that is relatively low in biomass, oligotrophic, and depleted in nutrients. Following initial colonization by microorganisms, glacial till sediments accumulate organic carbon and nutrients over time. However, the mechanisms driving soil nutrient stabilization during early pedogenesis after glacial retreat remain unclear. Here, we traced amino acid uptake by microorganisms in recently deglaciated high-Arctic soils and show that fungi play a critical role in the initial stabilization of the assimilated carbon. Pioneer basidiomycete yeasts were among the predominant taxa responsible for carbon assimilation, which were associated with overall high amino acid use efficiency and reduced respiration. In intermediate- and late-stage soils, lichenized ascomycete fungi were prevalent, but bacteria increasingly dominated amino acid assimilation, with substantially decreased fungal:bacterial amino acid assimilation ratios and increased respiration. Together, these findings demonstrate that fungi are important drivers of pedogenesis in high-Arctic ecosystems that are currently subject to widespread deglaciation from global warming.
A standalone and portable imaging detection system with embedded computing for automated defect inspection of microfluidic devices
Authors: Yang Shuo , Feng Xin , Wang Qingzheng , Xu Fan , Fan Yiqiang
Published: July 2024

The existing methods for defect detection in PDMS microfluidic chips typically involve complex image recognition algorithms or manual inspection and still lack efficiency and reliability. Although some automatic defect detection methods have been proposed in recent years, most of them still rely on external computation systems to deploy. To address these challenges, we propose an independent portable defect detection system with embedded computing for microfluidic devices. This portable system is completely self-contained, integrating an image acquisition module, a control panel module, a power module, and an embedded computing control module to realize chip detection, processing, and result display functions. Experimental results show that the system can effectively detect most of the commonly seen defects in PDMS-based microfluidic chips, proving to be more efficient and reliable than manual inspection. With the control of the embedded system, two detection methods: template matching (based on comparison with standard samples) and automatic defect detection (based on surface defect recognition) were used to identify defects in PDMS-based microfluidic chips. The proposed system can automatically inspect and analyze chips without the need for external laboratory support and can provide a promising solution for future microfluidic chip manufacturing and operation.
Progress of GaN-based E-mode HEMTs
Authors: Huang Huolin , Lei Yun , Sun Nan
Published: July 2024

With the continuous improvement of the power density and operating frequency in power conversion systems, it is necessary to develop the new power electronic products with better performances than the conventional semiconductors. As a typical representative of the wide-bandgap semiconductors, gallium nitride (GaN)-based heterostructure has unique high-density two-dimensional electron gas (2DEG) and hence can be used to fabricate the fast high electron mobility transistors (HEMTs) with low power loss. Therefore, it is considered as a promising candidate for the next-generation power devices to improve the switching efficiency and speed. Compared with the depletion mode (D-mode, also known as normally-on) devices, the enhancement-mode (E-mode, also known as normally-off) devices have the advantages of safety, energy-saving, and better circuit topology design, making them more attractive for industry applications. In this paper, the different structure schemes and fabrication technologies of the GaN-based E-mode HEMTs are reviewed and summarized. Their technical characteristics are systematically compared. The influences of material epitaxial structure, ohmic contact, material etching, field plate design, and passivation process on the device performances are discussed in detail wherein the fabrication process of the recessed-gate MIS-HEMTs are emphatically illustrated, focusing on the interface treatment technology and dielectric engineering. In addition, the complicated reliability issues in the E-mode HEMTs induced by high temperature, high voltage, and high frequency switching and corresponding physical mechanisms are introduced and discussed. Finally, the potential technical solutions are proposed and the future application fields of GaN-based E-mode HEMTs are prospected.
Effect of hydrogen poisoning on p-gate AlGaN/GaN HEMTs
Authors: He Zhiyuan , He Liang , Jiang Kun , Duan Xiaoyue , Shi Yijun , Chen Xinghuan , Chen Yuan , Wu Hualong , Lu Guoguang , Ni Yiqiang
Published: July 2024

In this work, we investigate the degradation behavior and mechanism of p-gate AlGaN/GaN high-electron mobility transistors (HEMTs) for the first time under hydrogen (H2) atmosphere. The experimental results reveal significant decrease in drain-to-source current, negative drift in threshold voltage, increase in off-state gate leakage current, and deterioration of subthreshold swing in the p-gate AlGaN/GaN HEMT after H2 treatment. The degradation of the electrical parameters is considered to hydrogen poisoning phenomenon. Through secondary ion mass spectrometry and variable temperature photoluminescence spectroscopy, we observe the increase in hydrogen concentration in the p-GaN layer and the formation of electrically inactive Mg–H complexes after H2 treatment. As results, the effective hole concentration decreases and the trap density of the device increases, which are confirmed by Hall effect measurement and low-frequency noise analysis, respectively. The detrimental effect of hydrogen on p-gate AlGaN/GaN HEMTs can be attributed primarily to the compensation of Mg doping and the generation of defects.
An effective method for improving GNSS precise point positioning performance at the day boundary
Authors: Xiao Jingxin , Li Haojun , Sun Yafeng , Liu Xiaolu
Published: July 2024

Aiming to address poor self-consistency of the satellite clock and orbit interpolations at the day boundary, which is caused by the discontinuities of their International GNSS Service (IGS) products for two consecutive days, an effective method is proposed to improve the precise point positioning (PPP) performances at the day boundary. According to different orders of Lagrange interpolator and different IGS Analysis Centers products of Center for Orbit Determination in Europe (CODE), GeoForschungsZentrum (GFZ) and Wuhan University (WUH), biases at the day boundaries are estimated and analyzed using a 4 day (DOY 94-97, 2022) data set of GPS, BDS-3 and Galileo from 123 IGS stations. These estimated biases show the time-varying characteristics. The differences in biases across 9th-11th orders of Lagrange interpolator are minimal, and these variances have a negligible impact on positioning. The results show that this poor self-consistency at the day boundary has an obvious influence on the kinematic PPP positioning, especially there is a centimeter-level variation at time of 24:00:00/00:00:00. This influence on the Up direction of kinematic PPP positioning is more serious than other directions. When the bias is estimated and corrected, the kinematic PPP positioning accuracies at the day boundary have a mean improvement of 0.043, 0.064 and 0.027 m for WUH, GFZ and CODE, respectively. The mean improvements for GPS, BDS-3 and Galileo are 0.021, 0.062 and 0.051 m. Additionally, the static PPP performances at the day boundary show the convergence times are shortened by 3.2, 6.2, and 2.5 min for WUH, GFZ and CODE, respectively, when the poor self-consistency of the satellite clock and orbit interpolations is estimated and corrected. Meanwhile, its 0.5 and 1 h positioning accuracies are improved.
Multi-rolling element faults diagnosis of rolling bearing based on time-frequency analysis and multi-curves extraction
Authors: Liu Xiru , Yan Changfeng , Lv Ming , Li Shengqiang , Wu Lixiao
Published: July 2024

In industrial production, rolling bearings are widely used as key mechanical components in all types of rotating machinery. Fault diagnosis is essential for predicting bearing damage in advance, avoiding sudden equipment downtime and reducing economic losses. However, rolling element fault diagnosis of rolling bearings continues to be a challenge, especially with multi-rolling element faults. In view of the characteristics of randomness, weakness, and coupling in the vibration signal generated by multi-rolling element faults in rolling bearings, a multi-rolling element fault detection method is proposed by combination time-frequency (TF) analysis with multi-curves extraction methods. The pre-processing method combined autoregressive model with maximum correlated kurtosis deconvolution is employed to enhance the weak periodic fault impulses in the raw vibration signals of the rolling bearing. Then an improved dynamic path multi-curves extraction method is proposed to extract multiple TF curves from the TF spectrogram (TFS) constructed via short-time Fourier transform. According to the proposed classification criteria, the TF curves are classified as homologous faults. The TF masking (TFM) method is employed to keep TF information closely associated with the fault impulse. Finally, the fault signals are reconstructed sequentially based on the TFS processed by TFM, and precise identification of multi-rolling element faults is achieved by envelope analysis. Experimental results demonstrate the effectiveness of the proposed method in extracting the weak fault features of multi-rolling elements and accomplishing fault separation and diagnosis.
Polycrystalline silicon, a molecular dynamics study: I. Deposition and growth modes
Authors: Santonen Mikael , Lahti Antti , Jahanshah Rad Zahra , Miettinen Mikko , Ebrahimzadeh Masoud , Lehtiö Juha-Pekka , Laukkanen Pekka , Punkkinen Marko , Paturi Petriina , Kokko Kalevi , Kuronen Antti , Li Wei , Vitos Levente , Parkkinen Katja , Eklund Markus
Published: July 2024

Polycrystalline silicon (poly-Si) significantly expands the properties of the ICT miracle material, silicon (Si). Depending on the grain size and shape and grain boundary structure, the properties of poly-Si exceed what single-crystal (c-Si) and amorphous (a-Si) silicon can offer, especially for radio frequency (RF) applications in microelectronics. Due to its wide range of applications and, on the one hand, its theoretically and technologically challenging microstructure, poly-Si research is the most timely (Ding et al 2020 Mater. Charact.
161 110174; Zhao and Li 2019 Acta Mater.
168 52–62). In this report, we describe how we simulate and analyse the phenomena and mechanisms that control the effect of poly-Si deposition parameters on the structure of the deposited poly-Si films using classical molecular dynamics simulations. The grain shape and size, degree of crystallinity, grain boundary structure and the stress of poly-Si films are determined depending on the growth temperature, temperature distribution in the growing film, deposition flux, flux variation and the energy transferred to the film surface due to the deposition flux. The main results include: (i) the dependence of the crystallinity profile of the deposited poly-Si films on the stress, temperature and the different parameters of the deposition flux, (ii) growth modes at the early stages of the deposition, (iii) interaction and stability of seed crystallites at the early stage of the deposition of poly-Si films and the transition from the isolated crystallite growth to the poly-Si growth, (iv) interplay of the temperature, crystallinity, crystal shape and heath conductivity of different Si phases, (v) four different stages of crystallite growth are described: nucleation, growth, disappearance and retardation.
Highly-efficient low-cost polarization-sensitive organic photodetectors based on laminated self-assembly planar and bulk heterojunctions
Authors: Zhang Chi , Shao Zhimin , Yu Feng , Cao Yunhao , Hou Lintao
Published: July 2024

To overcome the severe problems arising from the insufficient light absorption of ultrathin self-assembly active layers and the high cost use of atomic force deposition (ALD)-grown low-leakage-current transport layers, we successfully developed a low-cost, simple and facile strategy of floating-film transfer and multilayer lamination (FFTML) for constructing highly-efficient ALD-free broadband polarization-sensitive organic photodetectors (OPDs) with the two commonly used structures of donor/acceptor planar heterojunction (PHJ) and donor:acceptor multilayer bulk heterojunction (BHJ). It was found that the PHJ-based polarization-sensitive OPD by FFTML possesses a low dark current due to the high carrier injection barrier, indicating it is more suitable to be applied in low polarized light detection scenarios. In contrast, the BHJ-based device by FFTML has a higher spectral responsivity in the whole wavelength due to more photo-excitons transferred to the donor:acceptor interface and dissociated into photoexcited carrirers. Furthermore, the film thickness, which is tuned by increasing lamination number of BHJ layers, has a big effect on the polarization-sensitive photodetection performance. The polarization-sensitive 4-BHJ OPD by FFTML finally achieved a high specific detectivity of 8.33 × 1010 Jones, which was much higher than 2.72 × 1010 Jones for the 2-BHJ device at 0 V. This work demonstrates that layer-by-layer lamination of self-assembly films can effectively improve the polarized-light detection performance, contributing significantly to the rapid development of the field.
Simultaneous mapping of cathodoluminescence spectra and backscatter diffraction patterns in a scanning electron microscope
Authors: Edwards Paul R , Naresh Kumar G , McKendry Jonathan J D , Xie Enyuan , Gu Erdan , Dawson Martin D , Martin Robert W
Published: July 2024

Electron backscatter diffraction and cathodoluminescence are complementary scanning electron microscopy modes widely used in the characterisation of semiconductor films, respectively revealing the strain state of a crystalline material and the effect of this strain on the light emission from the sample. Conflicting beam, sample and detector geometries have meant it is not generally possible to acquire the two signals together during the same scan. Here, we present a method of achieving this simultaneous acquisition, by collecting the light emission through a transparent sample substrate. We apply this combination of techniques to investigate the strain field and resultant emission wavelength variation in a deep-ultraviolet micro-LED. For such compatible samples, this approach has the benefits of avoiding image alignment issues and minimising beam damage effects.
Developing an explainable diagnosis system utilizing deep learning model: a case study of spontaneous pneumothorax
Authors: Lin Frank Cheau-Feng , Wei Chia-Jung , Bai Zhe-Rui , Chang Chi-Chang , Chiu Ming-Chuan
Published: July 2024

Objective. The trend in the medical field is towards intelligent detection-based medical diagnostic systems. However, these methods are often seen as ‘black boxes’ due to their lack of interpretability. This situation presents challenges in identifying reasons for misdiagnoses and improving accuracy, which leads to potential risks of misdiagnosis and delayed treatment. Therefore, how to enhance the interpretability of diagnostic models is crucial for improving patient outcomes and reducing treatment delays. So far, only limited researches exist on deep learning-based prediction of spontaneous pneumothorax, a pulmonary disease that affects lung ventilation and venous return. Approach. This study develops an integrated medical image analysis system using explainable deep learning model for image recognition and visualization to achieve an interpretable automatic diagnosis process. Main results. The system achieves an impressive 95.56% accuracy in pneumothorax classification, which emphasizes the significance of the blood vessel penetration defect in clinical judgment. Significance. This would lead to improve model trustworthiness, reduce uncertainty, and accurate diagnosis of various lung diseases, which results in better medical outcomes for patients and better utilization of medical resources. Future research can focus on implementing new deep learning models to detect and diagnose other lung diseases that can enhance the generalizability of this system.
New approach to measuring topological phase transitions utilizing Floquet technology
Authors: Yang 杨 Xue-Ying 雪滢 , Wu 吴 Wei 伟 , Chen 陈 Ping-Xing 平形
Published: July 2024

The Floquet technique provides a novel anomalous topological phase for non-equilibrium phase transitions. Based on the high symmetry of the quantum anomalous Hall model, the findings suggest a one-to-one correspondence between the average spin texture and the Floquet quasi-energy spectrum. A new approach is proposed to directly measure the quasi-energy spectrum, replacing previous measurements of the average spin texture. Finally, we proposed a reliable experimental scheme based on ion trap platforms. This scheme markedly reduces the measurement workload, improves the measurement fidelity, and is applicable to multiple platforms such as cold atoms and nuclear magnetic resonance.
Evaluation of the activation of the radiation shielding of the LaDiff neutron triple-axis-spectrometer at FRM-II by simulation/calculation
Authors: Grünauer F. , Keller T. , Georgii R. , Skoulatos M.
Published: July 2024

Neutron radiation is widely used for investigation of matter
at research reactors and spallation sources. One undesired
side-effect is the production of radioactive nuclides in structure
materials of the instruments (e.g. mounting structures and
radiation shieldings) due to neutron capture reactions. Hence the
structure materials themselves become radiation sources. The
knowledge of the activities after a certain time of operation is
essential for determination of the accessibility, for modifications
of the instrument, for reusing the material and for waste
management. It is desirable to have these data in the design phase
of the instrument. One possibility to obtain the data is a
combination of simulation and calculation. In this paper the
simulations/calculations for the LaDiff cold triple-axis neutron
spectrometer project at FRM-II (research reactor Munich) are
presented. The activities in the shielding house around the
experimental area of the instrument made from stainless steel and
lead are considered for the cases with and without boron-carbide
cover and for different Sb-contents of the lead layer. The influence
of the skyshine is also considered.
Public attitudes and emotions toward novel carbon removal methods in alternative sociotechnical scenarios
Authors: Cox Emily , Bellamy Rob , Waller Laurie
Published: July 2024

Despite high expectations about the role of carbon removal in meeting global climate targets, many of the proposed techniques remain nascent. This is especially so for techniques with potential for large-scale, permanent removal of CO2, such as direct air carbon capture and storage (DACCS) and ocean alkalinity enhancement (OAE). In such a context, understanding public attitudes is crucial but challenging, since we do not have enough information about the sociotechnical configurations which might accompany such proposals over future timescales. Carbon removal at scale will not take place in a vacuum—it will co-evolve within political, social, economic, and legal structures which in turn will have a strong influence on public attitudes. This study used a nationally-representative survey (n = 1978) in the UK to test the impact of alternative sociotechnical systems on public attitudes to DACCS and OAE. Participants were randomly assigned to one of five scenario conditions, representing different forms of governance logic (top–down vs bottom–up) and market logic (planned vs liberal economy), plus one with minimal sociotechnical information. We find that the scenario condition significantly impacted perceptions of OAE, with participants preferring its implementation within a bottom–up, planned economy scenario, and rejecting scenarios which most closely resembled the status quo. There were no significant differences between scenarios for DACCS, suggesting that the technology may be more flexible across alternative sociotechnical arrangements. OAE arouses more negative emotions, particularly worry about impacts on ocean ecosystems, whereas DACCS arouses more hope. We found that climate worry is associated with stronger emotions—both positive and negative—toward both techniques, thus carbon dioxide removal (CDR) could be polarising for the most climate-worried, likely due to tensions between climate urgency and concerns about deterring emissions reductions. The most important criteria for future CDR deployment were deemed to be biodiversity, durability, and cost, with a strong discourse around the current cost-of-living crisis.
Lattice Boltzmann method for the linear complementarity problem arising from American option pricing
Authors: Wu Fangfang , Zhang Yi , Wang Yingying , Zhang Qi
Published: July 2024

In this paper, a lattice Boltzmann method is proposed for solving the linear complementarity problem (LCP) arising in single and multi-asset American put option pricing. The LCP for American option is a variable coefficient parabolic model defined on an unbounded domain. Initially, using the far field estimate method and the penalty method respectively, the LCP could be reformulated into a nonlinear parabolic partial differential equation on a bounded domain. To construct a unified lattice Boltzmann model for the option pricing problems, the above transformation equations are rewritten into an equivalent divergence form. Then, through the incorporation of an amending function into the evolution equation, which assists in recovering the source term and eliminating the error term, the lattice Boltzmann model with spatial second-order accuracy is constructed. Finally, the present model is validated using numerical simulations, and the numerical results agree well with the option values obtained by existing methods, which indicates that the present lattice Boltzmann model is efficient for solving the American put option pricing problem.
Corrosion mitigation of 6061 aluminium alloy hybrid metal matrix composite using a green inhibitor: experimental and theoretical investigations
Authors: M Lavanya , Hegde Bhavya , Gaonkar Santhosh L , M C Gowri Shankar , Sinha Rajeev K , Kumari P Preethi
Published: July 2024

Carbohydrate compounds are recognized potent green corrosion inhibitors owing to their structural properties and eco-friendliness. This study showed the effectiveness of glucosamine sulfate (GAS), an eco-friendly green inhibitor, in mitigating the deterioration of 6061 aluminium alloy reinforced with 2% SiC and 2% B4C hybrid composite (6061AA-HMMC) material in 0.1 M hydrochloric acid (HCl) medium. Electrochemical measurements were carried out to quantify the corrosion rate in the absence and presence of the GAS. The results were included in an acceptable adsorption isotherm model, and a suitable mechanism for the corrosion inhibition process was discussed in detail. To comprehend the method of adsorption, the Freundlich isotherm model was applied. Different characterization techniques were used to verify the adsorption of the investigated inhibitor. The optimized structure of the GAS was analysed using density functional theory to provide further insight into its interaction with the metal surface. The infrared (IR) and UV-visible (UV) spectra for the adsorption of the inhibitor molecule were compared with the IR and UV spectra calculated by B3LYP/6-311++G(d, p).
Single channel speech enhancement using time-frequency attention mechanism based nested U-net model
Authors: Prathipati Anil Kumar , Chakravarthy A S N
Published: July 2024

Deep-learning models have used attention mechanisms to improve quality and intelligibility of noisy speech, demonstrating the effectiveness of attention mechanisms. We rely on either spatial or temporal-based attention mechanisms, resulting in severe information loss. In this paper, a time-frequency attention mechanism with a nested U-network (TFANUNet) is proposed for single-channel speech enhancement. By using TFA, learns which channel, frequency and time information is more significant for speech enhancement. Basically, the proposed model is an encoder-decoder model, where each layer in the encoder and decoder is followed by a nested dense residual dilated DensNet (NDRD) based multi-scale context aggression block. NDRD involves multiple dilated convolutions with different dilatation factors to explore the large receptive area at different scales simultaneously. NDRD avoids the aliasing problem in DenseNet. We integrated the TFA and NDRD blocks into the proposed model to enable refined feature set extraction without information loss and utterance-level context aggregation, respectively. Under seen and unseen noise conditions, the proposed TFAD3MNet model produces an average of 87.02% and 85.04% of STOI values, and 3.19 and 3.01 averaged PESQ values. The trainable parameters of proposed model are 2.09 million,which is very less compared to baselines. TFANUNet model results outperform baselines in terms of STOI and PESQ.
Copernican Revolution or Green Protectionism?
Authors: Meyer Timothy
Published: July 2024

Contemporary trade agreements include an ever-expanding set of environmental and sustainability commitments. Likewise, the world’s leading developed economies have begun rolling out green trade barriers in the form of product bans, border adjustments, and discriminatory subsidies. This chapter argues that the growth of sustainable trade policies reflects two phenomena. First, it reflects the ordinary historical ebb and flow of unilateralism and multilateralism. While at some points in history multilateral institutions have taken the lead in shaping trade policy, at other times unilateralism has played a more important role. Second, green trade policies usually pursue multiple objectives. This fact means that assessing their effects through a Puritan lens is a fool’s errand. The quest nations are on today is not for trade policies that promote sustainability in the least trade-restrictive way possible. It is for policies that generate the political support to address urgent environmental crises while still promoting economic growth.
The Road Ahead
Authors: Claussen Kathleen , Vidigal Geraldo
Published: July 2024

This chapter takes stock of the conclusions reached in the contributions to this volume. We examine the findings in the various chapters, consider the work that remains to be undertaken in this field, and survey new challenges in the formulation of agreements affecting trade that pursue a mix of environmental, social, and economic objectives. The road ahead for sustainability provisions in trade agreements is to some degree unknowable. Just as revolutions sometimes spur counter-revolutions, there are forces working against this turn, economically and legally. Continued demand for provisions of this kind suggests to us that attention to these issues is likely to increase, while the forms and designs of the agreements that further these aims continue to evolve.
Predictive features for effectiveness of dupilumab in elderly patients with atopic dermatitis: a real-world study
Authors: Jia Qiqi , Cao Qiaozhi , Peng Cong , Shui Xinyu , Li Jie
Published: July 2024

In this study we retrospectively reviewed dupilumab’s efficacy and safety profile in treating elderly patients with atopic dermatitis (AD) and explored the predictive indicators for its efficacy. After analysing data from 181 patients we found that dupilumab appears to be effective and well-tolerated in treating AD among elderly patients. More importantly, we found that disease severity and early response to dupilumab are associated with complete remission at week 24 and may be used as potential predictive indicators for dupilumab’s efficacy.
The NLRP3 inflammasome in burns: a novel potential therapeutic target
Authors: Li Haihong , Zhao Junhong , Cao Leilei , Luo Qizhi , Zhang Cuiping , Zhang Lei
Published: July 2024

Burns are an underestimated serious injury negatively impacting survivors physically, psychologically and economically, and thus are a considerable public health burden. Despite significant advancements in burn treatment, many burns still do not heal or develop serious complications/sequelae. The nucleotide-binding oligomerization domain-like receptors (NLRs) family pyrin domain-containing 3 (NLRP3) inflammasome is a critical regulator of wound healing, including burn wound healing. A better understanding of the pathophysiological mechanism underlying the healing of burn wounds may help find optimal therapeutic targets to promote the healing of burn wounds, reduce complications/sequelae following burn, and maximize the restoration of structure and function of burn skin. This review aimed to summarize current understanding of the roles and regulatory mechanisms of the NLRP3 inflammasome in burn wound healing, as well as the preclinical studies of the involvement of NLRP3 inhibitors in burn treatment, highlighting the potential application of NLRP3-targeted therapy in burn wounds.
Exercise-induced complete atrioventricular block resulting in cardiac arrest: a case report and review of diagnostic strategies
Authors: Braga Fabrício , Bessa Tácito , Cunha Matheus , Bueno Paiva Roberto , Stein Ricardo
Published: July 2024

Background

Exercise-induced complete atrioventricular block (EIAVB) is a rare cardiac conduction abnormality presenting challenges in diagnosis due to non-specific symptoms such as exertional dyspnoea, dizziness, and syncope.

Case summary

We present a case of a 76-year-old female with recurrent exercise-associated syncope. Non-invasive exercise testing played a crucial role in diagnosing her condition, revealing EIAVB and underscoring its importance in patients with cardiovascular risk factors.

Discussion

This case provides insight into the pathophysiology of EIAVB, including altered atrioventricular nodal refractoriness and exercise-induced ischaemic imbalances. It highlights the need for heightened clinical vigilance in diagnosing exercise-related syncope, especially in pre-existing cardiovascular conditions. This case underscores the critical importance of non-invasive testing for diagnosing EIAVB, highlighting the necessity of thorough evaluation in patients presenting with ambiguous symptoms and cardiovascular risks. Consequently, it advocates for adherence to guidelines to enhance outcomes and reduce the need for unnecessary invasive procedures.
Efficacy of an expandable prosthesis placement after left pneumonectomy for soft tissue Ewing sarcoma in a 5-year-old child: 10 years follow-up
Authors: Langeron Margaux , Khen-Dunlop Naziha , Helfre Sylvie , Sarnacki Sabine
Published: July 2024

We report the case of a 5-year-old girl who underwent left pneumonectomy for Ewing sarcoma of the lung. Two expandable prostheses were placed in the left hemi-thorax to prevent post-pneumonectomy syndrome and to protect the heart from radiotherapy. With a follow-up of 10 years, the procedure proved to be effective both on post-pneumonectomy syndrome and on cardiac protection.
Procedural and Intermediate-term Results of the Electroanatomical-guided Cardioneuroablation for the Treatment of Supra-Hisian Second- or Advanced-degree Atrioventricular Block: the PIRECNA multicentre registry
Authors: Aksu Tolga , Piotrowski Roman , Tung Roderick , De Potter Tom , Markman Timothy M , du Fay de Lavallaz Jeanne , Rekvava Roin , Alyesh Daniel , Joza Jacqueline E , Badertscher Patrick , Do Duc H , Bradfield Jason S , Upadhyay Gaurav , Sood Nitesh , Sharma Parikshit S , Guler Tumer Erdem , Gul Enes Elvin , Kumar Vineet , Koektuerk Buelent , Dal Forno Alexander Romeno Janner , Woods Christopher E , Rav-Acha Moshe , Valeriano Chiara , Enriquez Andres , Sundaram Sri , Glikson Michael , d’Avila Andre , Shivkumar Kalyanam , Kulakowski Piotr , Huang Henry D
Published: July 2024

Aims

Prior case series showed promising results for cardioneuroablation in patients with vagally induced atrioventricular blocks (VAVBs). We aimed to examine the acute procedural characteristics and intermediate-term outcomes of electroanatomical-guided cardioneuroablation (EACNA) in patients with VAVB.

Methods and results

This international multicentre retrospective registry included data collected from 20 centres. Patients presenting with symptomatic paroxysmal or persistent VAVB were included in the study. All patients underwent EACNA. Procedural success was defined by the acute reversal of atrioventricular blocks (AVBs) and complete abolition of atropine response. The primary outcome was occurrence of syncope and daytime second- or advanced-degree AVB on serial prolonged electrocardiogram monitoring during follow-up. A total of 130 patients underwent EACNA. Acute procedural success was achieved in 96.2% of the cases. During a median follow-up of 300 days (150, 496), the primary outcome occurred in 17/125 (14%) cases with acute procedural success (recurrence of AVB in 9 and new syncope in 8 cases). Operator experience and use of extracardiac vagal stimulation were similar for patients with and without primary outcomes. A history of atrial fibrillation, hypertension, and coronary artery disease was associated with a higher primary outcome occurrence. Only four patients with primary outcome required pacemaker placement during follow-up.

Conclusion

This is the largest multicentre study demonstrating the feasibility of EACNA with encouraging intermediate-term outcomes in selected patients with VAVB. Studies investigating the effect on burden of daytime symptoms caused by the AVB are required to confirm these findings.
Severe aortic stenosis treated with transcatheter aortic valve implantation or surgical aortic valve replacement with Perimount in Western Denmark 2016–2022: a nationwide retrospective study
Authors: Krasniqi Lytfi , Brandes Axel , Mortensen Poul Erik , Gerke Oke , Riber Lars
Published: June 2024

OBJECTIVES

The healthcare registries in Denmark present a unique opportunity to gain novel insights into the outcomes associated with both transcatheter and surgical approaches to aortic valve replacement. Our objective is to enhance shared decision-making by comparing long-term mortality and clinical outcomes between treatments.

METHODS

This observational study included all patients with severe aortic stenosis undergoing elective isolated transfemoral transcatheter aortic valve implantation (TAVI) or surgical aortic valve replacement (SAVR) in Western Denmark between January 2016 and April 2022. Patient population and clinical data were identified from the Western Danish Heart Registry and the National Danish Patient Registry, respectively. A propensity score-matched population was generated. Outcomes were investigated according to Valve Academic Research Consortium-3.

RESULTS

A total of 2269 TAVI patients and 1094 SAVR patients where identified. The propensity score-matched population consisted of 468 TAVI patients (mean[SD]age, 75.0[5.3] years) and 468 SAVR patients (mean[SD] age, 75.1[4.6]years). The Kaplan–Meier estimate for the 5-year all-cause mortality was 29.8% in the TAVI group and 16.9% for in the SAVR group (P = 0.019). The risk of all stroke or transient ischaemic attack after five year was 15.1% in the TAVI group and 11.0% in the SAVR group (P = 0.047).

CONCLUSIONS

This study underscores the importance of evaluating all patient factors when choosing an aortic valve replacement method. Surgical aortic valve replacement was an excellent choice, especially for patients with New York Heart Association class I/II, ≥75 age, left ventricular ejection fraction ≥50%, or longer life expectancy.
Thinking the Aesthetic: Towards a Noetic Conception of Aesthetic Experience The 2023 Richard Wollheim Memorial Lecture
Authors: Schellekens Elisabeth
Published: July 2024

This paper defends a ‘noetic’ conception of aesthetic experience whereby such experience is best conceived as a kind of explorative thought process. Although not directly aimed at acquiring knowledge, this process often leads to an enhanced understanding or improved epistemic grasp of the object of appreciation itself and the world. On this conception, aesthetic value acts as an invitation to engage in a series of contemplative and reflective processes during which we rely not only on the perceptual, imaginative, and affective abilities which have occupied such a central role in aesthetic theory, but also on our capacities for sense-making, problem-solving and theory-building. Cases of intelligible beauty or aesthetic value should thus lie at the heart of accounts of aesthetic experience.
Genetic background of aminoglycoside-modifying enzymes in various genetic lineages of clinical aminoglycosides-resistant E. coli and K. pneumoniae isolates in Tunisia
Authors: Harbaoui Sarra , Ferjani Sana , Abbassi Mohamed Salah , Guzmán-Puche Julia , Causse Manuel , Elías-López Cristina , Martínez-Martínez Luis , Boubaker Ilhem Boutiba-Ben
Published: July 2024

Aims

This study was conducted to evaluate the in vitro activity of clinically relevant aminoglycosides and to determine the prevalence of genes encoding aminoglycoside modifying enzymes (AMEs) and 16S ribosomal RNA (rRNA) methyltransferases among aminoglycoside-resistant E. coli (n = 61) and K. pneumoniae (n = 44) clinical isolates. Associated resistances to beta–lactams and their bla genes as well as the genetic relatedness of isolates were also investigated.

Materials and methods

A total of 105 aminoglycoside-resistant E. coli (n = 61) and K. pneumoniae (n = 44) isolates recovered between March and May 2017 from 100 patients hospitalized in different wards of Charles Nicolle Hospital of Tunis, Tunisia, were studied. Minimal inhibitory concentrations of aminoglycoside compounds were determined by broth microdilution method. Aminoglycosides resistance encoding genes [aph(3´)-Ia, aph(3′) IIa, aph(3´)-VIa, ant(2″)-Ia, aac(3)-IIa, aac(3)-IVa, aac(6′)-Ib, rmtA, rmtB, rmtC, armA, and npmA] and bla genes were investigated by PCR and sequencing. Genetic relatedness was examined by multilocus sequence typing (MLST) for representative isolates.

Results

High rates of aminoglycoside resistance were found: gentamicin (85.7%), tobramycin (87.6%), kanamycin (78.0%), netilmincin (74.3%), and amikcin (18.0%). Most common AME gene was aac(3)-IIa (42%), followed by aac(6′)-Ib (36.2%) and aph(3′)-VIa (32.4%). The majority of isolates were resistant to beta–lactams and blaCTX-M-15 was the most common ESBL. The blaNDM-1 and blaOXA-48 were also produced by 1 and 23 isolates, respectively. Novel sequence types have been reported among our isolates and high-risk clonal lineages have been detected, such as E. coli ST43 (ST131 in Achtman MLST scheme) and K. pneumoniae (ST11/ST13).

Conclusions

The high prevalence of aminoglycoside resistance rates and the diversity of corresponding genes, with diverse β-lactamase enzymes among genetically heterogeneous clinical isolates present a matter of concern.
Incorporating body measurement traits to increase genetic gain of feed efficiency and carcass traits in Japanese Black steers
Authors: Kemmotsu Nodoka , Takeda Masayuki , Ogino Atsushi , Watanabe Toshio , Kurogi Kazuhito , Satoh Masahiro , Uemoto Yoshinobu
Published: June 2024

The objective of the present study was to comprehensively evaluate whether body measurement traits, including body weight and body size, could be used as indicators of genetic selection for feed efficiency and carcass traits in Japanese Black steers. First, we estimated the genetic parameters for body measurements, feed efficiency, and carcass traits. Second, we estimated the correlated responses in feed efficiency and carcass traits when selection was applied to one or multiple-body measurement traits. In total, 4,578 Japanese Black steers with phenotypic values of residual feed intake (RFI) and residual body weight gain (RG) as feed efficiency traits and carcass weight (CWT) and beef marbling standard (BMS) as carcass traits were used. Eleven body measurement traits were measured at the start and finish of the fattening periods (BMT1 and BMT2, respectively), and their growth during the fattening period (BMT3) was used for genetic analyses. The results of genetic parameters showed that the heritability estimates were low to moderate (0.10 to 0.66), and the genetic correlations among body measurement traits were also estimated to be positively moderate to high in each measuring point (0.23 to 0.99). The genetic correlations of body measurement traits with RFI and BMS were estimated to be low (−0.14 to 0.30 and −0.17 to 0.35, respectively), but those with CWT were positively low to high (0.12 to 0.97). The genetic correlation estimates between BMT3 and RG were moderate to high (0.38 to 0.78). Second, correlated responses were estimated under positive selection for body measurement traits. Positive selection for BMT2 and BMT3 increased CWT and RG; however, positive selection for body measurement traits resulted in no change in RFI and BMS. Favorable directions of genetic gains, which were positive for RG, CWT, and BMS and negative for RFI, were obtained by selection indices, including multiple traits in BMT1. Our results suggest that using only one-body measurement trait as an indicator of genetic selection for RFI is difficult. However, body measurement traits can be indirect indicators of improved RG. Our results also suggest that genetic improvement of both RFI and RG without reducing CWT and BMS could be achieved using selection indices that account for a balance of body conformation using multiple-body measurement traits in Japanese Black cattle.
Prohibiting the use of biological weapons: diverging national measures, a comparative analysis
Authors: de Vries Barry
Published: July 2024

To ensure an effective international prohibition on the use of biological weapons, an international framework of national prohibitions needs to exist. This article looks comparatively at the national prohibitions on the use of biological weapons and considers the effect of common approaches. This research is based on a near-comprehensive collection of national legislation addressing the use of biological weapons. Investigating the common approaches allows for the identification of potential gaps within the international framework of national prohibitions, indicating the potential benefit of developing an international obligation to implement national measures prohibiting the use of biological weapons.
The evolution of evolutionary linguistics
Authors: Brar Poonam , Camargo Chico Q
Published: July 2024

This paper presents a scientometric study of the evolution of evolutionary linguistics, a multidisciplinary field that investigates the origin and evolution of language. We apply network science methods to analyse changes in the connections among core concepts discussed in the Causal Hypotheses in Evolutionary Linguistics Database, a searchable database of causal hypotheses in evolutionary linguistics. Our analysis includes a multipartite network of 416 papers, 742 authors, and 1,786 variables such as ‘population birth rate’ and ‘linguistic complexity’. Our findings indicate a significant increase in the size of concept networks from 1886 to 2022, providing an account of the growth and diversification of evolutionary linguistics as a field. We describe eight major clusters of concepts, and characterize the connections within and between clusters. Finally, we identify hypotheses cutting across clusters of concepts that have a high-betweenness centrality, implying that they might have a higher impact on the field if proven right (or wrong). Furthermore, we discuss the role of databases in cultural evolution and scientometrics, emphasizing the value of interdisciplinary connections and the potential for further cross-disciplinary collaboration in the field of Evolutionary Linguistics.
Galaxy Zoo DESI: large-scale bars as a secular mechanism for triggering AGNs
Authors: Garland Izzy L , Walmsley Mike , Silcock Maddie S , Potts Leah M , Smith Josh , Simmons Brooke D , Lintott Chris J , Smethurst Rebecca J , Dawson James M , Keel William C , Kruk Sandor , Mantha Kameswara Bharadwaj , Masters Karen L , O’Ryan David , Popp Jürgen J , Thorne Matthew R
Published: July 2024

Despite the evidence that supermassive black holes (SMBHs) co-evolve with their host galaxy, and that most of the growth of these SMBHs occurs via merger-free processes, the underlying mechanisms which drive this secular co-evolution are poorly understood. We investigate the role that both strong and weak large-scale galactic bars play in mediating this relationship. Using 48 871 disc galaxies in a volume-limited sample from Galaxy Zoo DESI, we analyse the active galactic nucleus (AGN) fraction in strongly barred, weakly barred, and unbarred galaxies up to $z = 0.1$ over a range of stellar masses and colours. After controlling for stellar mass and colour, we find that the optically selected AGN fraction is $31.6 \pm 0.9$ per cent in strongly barred galaxies, $23.3 \pm 0.8$ per cent in weakly barred galaxies, and $14.2 \pm 0.6$ per cent in unbarred disc galaxies. These are highly statistically robust results, strengthening the tantalizing results in earlier works. Strongly barred galaxies have a higher fraction of AGNs than weakly barred galaxies, which in turn have a higher fraction than unbarred galaxies. Thus, while bars are not required in order to grow an SMBH in a disc galaxy, large-scale galactic bars appear to facilitate AGN fuelling, and the presence of a strong bar makes a disc galaxy more than twice as likely to host an AGN than an unbarred galaxy at all galaxy stellar masses and colours.
The impact of shear on the rotation of Galactic plane molecular clouds
Authors: Rani Raffaele , Li Jia-Lun , Moore Toby J T , Eden David J , Rigby Andrew J , Park Geumsook , Lee Yueh-Ning
Published: July 2024

Stars form in the densest regions of molecular clouds; however, there is no universal understanding of the factors that regulate cloud dynamics and their influence on the gas-to-star conversion. This study considers the impact of Galactic shear on the rotation of giant molecular clouds (GMCs) and its relation to the solenoidal modes of turbulence. We estimate the direction of rotation for a large sample of clouds in the $\mathrm{^{13}CO}$/$\mathrm{C^{18}O}$(3–2) Heterodyne Inner Milky Way Plane Survey (CHIMPS) and their corresponding sources in a new segmentation of the $\mathrm{^{12}CO}$(3–2) High-Resolution Survey. To quantify the strength of shear, we introduce a parameter that describes the shear’s ability to disrupt growing density perturbations within the cloud. Although we find no correlation between the direction of cloud rotation, the shear parameter, and the magnitude of the velocity gradient, the solenoidal fraction of the turbulence in the CHIMPS sample is positively correlated with the shear parameter and behaves similarly when plotted over Galactocentric distance. GMCs may thus not be large or long-lived enough to be affected by shear to the point of showing rotational alignment. In theory, Galactic shear can facilitate the rise of solenoidal turbulence and thus contribute to suppressing star formation. These results also suggest that the rotation of clouds is not strictly related to the overall rotation of the disc, but is more likely to be the imprint of Kelvin–Helmholtz instabilities in the colliding flows that formed the clouds.