bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of machine learning to improve the estimation of conductivity and permittivity based on longitudinal relaxation time T1 in magnetic resonance at 7 T
Authors: Hernandez Daniel , Kim Kyoung-Nam 
Published: May 2023

AbstractElectrical property tomography (EPT) is a noninvasive method that uses magnetic resonance imaging (MRI) to estimate the conductivity and permittivity of tissues, and hence, can be used as a biomarker. One branch of EPT is based on the correlation of water and relaxation time T1 with the conductivity and permittivity of tissues. This correlation was applied to a curve-fitting function to estimate electrical properties, it was found to have a high correlation between permittivity and T1 however the computation of conductivity based on T1 requires to estimate the water content. In this study, we developed multiple phantoms with several ingredients that modify the conductivity and permittivity and explored the use of machine learning algorithms to have a direct estimation of conductivity and permittivity based on MR images and the relaxation time T1. To train the algorithms, each phantom was measured using a dielectric measurement device to acquire the true conductivity and permittivity. MR images were taken for each phantom, and the T1 values were measured. Then, the acquired data were tested using curve fitting, regression learning, and neural fit models to estimate the conductivity and permittivity values based on the T1 values. In particular, the regression learning algorithm based on Gaussian process regression showed high accuracy with a coefficient of determination R2 of 0.96 and 0.99 for permittivity and conductivity, respectively. The estimation of permittivity using regression learning demonstrated a lower mean error of 0.66% compared to the curve fitting method, which resulted in a mean error of 3.6%. The estimation of conductivity also showed that the regression learning approach had a lower mean error of 0.49%, whereas the curve fitting method resulted in a mean error of 6%. The findings suggest that utilizing regression learning models, specifically Gaussian process regression, can result in more accurate estimations for both permittivity and conductivity compared to other methods.
Synthesis, in vitro inhibitor screening, structure–activity relationship, and molecular dynamic simulation studies of novel thioquinoline derivatives as potent α-glucosidase inhibitors
Authors: Forozan RasaDokht , Ghomi Minoo Khalili , Iraji Aida , Montazer Mohammad Nazari , Noori Milad , Dastyafteh Navid , Mojtabavi Somayeh , Faramarzi Mohammad Ali , Sadat-Ebrahimi Seyed Esmaeil , Larijani Bagher , Javanshir Shahrzad , Mahdavi Mohammad 
Published: May 2023

AbstractNew series of thioquinoline structures bearing phenylacetamide 9a–p were designed, synthesized and the structure of all derivatives was confirmed using different spectroscopic techniques including FTIR, 1H-NMR, 13C-NMR, ESI–MS and elemental analysis. Next, the α-glucosidase inhibitory activities of derivatives were also determined and all the synthesized compounds (IC50 = 14.0 ± 0.6–373.85 ± 0.8 μM) were more potent than standard inhibitors acarbose (IC50 = 752.0 ± 2.0 μM) against α-glucosidase. Structure–activity relationships (SARs) were rationalized by analyzing the substituents effects and it was shown that mostly, electron-donating groups at the R position are more favorable compared to the electron-withdrawing group. Kinetic studies of the most potent derivative, 9m, carrying 2,6-dimethylphenyl exhibited a competitive mode of inhibition with Ki value of 18.0 µM. Furthermore, based on the molecular dynamic studies, compound 9m depicted noticeable interactions with the α-glucosidase active site via several H-bound, hydrophobic and hydrophilic interactions. These interactions cause interfering catalytic potential which significantly decreased the α-glucosidase activity.
Methanol fixation is the method of choice for droplet-based single-cell transcriptomics of neural cells
Authors: Gutiérrez-Franco Ana , Ake Franz , Hassan Mohamed N. , Cayuela Natalie Chaves , Mularoni Loris , Plass Mireya 
Published: May 2023

AbstractThe main critical step in single-cell transcriptomics is sample preparation. Several methods have been developed to preserve cells after dissociation to uncouple sample handling from library preparation. Yet, the suitability of these methods depends on the cell types to be processed. In this project, we perform a systematic comparison of preservation methods for droplet-based single-cell RNA-seq on neural and glial cells derived from induced pluripotent stem cells. Our results show that while DMSO provides the highest cell quality in terms of RNA molecules and genes detected per cell, it strongly affects the cellular composition and induces the expression of stress and apoptosis genes. In contrast, methanol fixed samples display a cellular composition similar to fresh samples and provide a good cell quality and little expression biases. Taken together, our results show that methanol fixation is the method of choice for performing droplet-based single-cell transcriptomics experiments on neural cell populations.
Fine-mapping of retinal vascular complexity loci identifies Notch regulation as a shared mechanism with myocardial infarction outcomes
Authors: Villaplana-Velasco Ana , Pigeyre Marie , Engelmann Justin , Rawlik Konrad , Canela-Xandri Oriol , Tochel Claire , Lona-Durazo Frida , Mookiah Muthu Rama Krishnan , Doney Alex , Parra Esteban J. , Trucco Emanuele , MacGillivray Tom , Rannikmae Kristiina , Tenesa Albert , Pairo-Castineira Erola , Bernabeu Miguel O. 
Published: May 2023

AbstractThere is increasing evidence that the complexity of the retinal vasculature measured as fractal dimension, Df, might offer earlier insights into the progression of coronary artery disease (CAD) before traditional biomarkers can be detected. This association could be partly explained by a common genetic basis; however, the genetic component of Df is poorly understood. We present a genome-wide association study (GWAS) of 38,000 individuals with white British ancestry from the UK Biobank aimed to comprehensively study the genetic component of Df and analyse its relationship with CAD. We replicated 5 Df loci and found 4 additional loci with suggestive significance (P < 1e−05) to contribute to Df variation, which previously were reported in retinal tortuosity and complexity, hypertension, and CAD studies. Significant negative genetic correlation estimates support the inverse relationship between Df and CAD, and between Df and myocardial infarction (MI), one of CAD’s fatal outcomes. Fine-mapping of Df loci revealed Notch signalling regulatory variants supporting a shared mechanism with MI outcomes. We developed a predictive model for MI incident cases, recorded over a 10-year period following clinical and ophthalmic evaluation, combining clinical information, Df, and a CAD polygenic risk score. Internal cross-validation demonstrated a considerable improvement in the area under the curve (AUC) of our predictive model (AUC = 0.770 ± 0.001) when comparing with an established risk model, SCORE, (AUC = 0.741 ± 0.002) and extensions thereof leveraging the PRS (AUC = 0.728 ± 0.001). This evidences that Df provides risk information beyond demographic, lifestyle, and genetic risk factors. Our findings shed new light on the genetic basis of Df, unveiling a common control with MI, and highlighting the benefits of its application in individualised MI risk prediction.
Multi-omics delineation of cytokine-induced endothelial inflammatory states
Authors: Groten Stijn A. , Smit Eva R. , Janssen Esmée F. J. , van den Eshof Bart L. , van Alphen Floris P. J. , van der Zwaan Carmen , Meijer Alexander B. , Hoogendijk Arie J. , van den Biggelaar Maartje 
Published: May 2023

AbstractVascular endothelial cells (ECs) form a dynamic interface between blood and tissue and play a crucial role in the progression of vascular inflammation. Here, we aim to dissect the system-wide molecular mechanisms of inflammatory endothelial-cytokine responses. Applying an unbiased cytokine library, we determined that TNFα and IFNγ induced the largest EC response resulting in distinct proteomic inflammatory signatures. Notably, combined TNFα + IFNγ stimulation induced an additional synergetic inflammatory signature. We employed a multi-omics approach to dissect these inflammatory states, combining (phospho-) proteome, transcriptome and secretome and found, depending on the stimulus, a wide-array of altered immune-modulating processes, including complement proteins, MHC complexes and distinct secretory cytokines. Synergy resulted in cooperative activation of transcript induction. This resource describes the intricate molecular mechanisms that are at the basis of endothelial inflammation and supports the adaptive immunomodulatory role of the endothelium in host defense and vascular inflammation.
Akt2 deficiency alleviates oxidative stress in the heart and liver via up-regulating SIRT6 during high-fat diet-induced obesity
Authors: Kong Weixian , Peng Yue , Ji Caoyu , Liu Zekun , Gao Shuya , Zhang Yuexin , Chen Jiawen , Li Xie , Bao Mengmeng , Zhang Yubin , Jiang Qizhou , Wang Fuqun , Li Zhe , Bian Xiaohong , Ye Junmei 
Published: May 2023

Abstract
The present study aims to investigate the role of AKT2 in the pathogenesis of hepatic and cardiac lipotoxicity induced by lipid overload-induced obesity and identify its downstream targets. WT and Akt2 KO mice were fed either normal diet, or high-fat diet (HFD) to induce obesity model in vivo. Human hepatic cell line (L02 cells) and neonatal rat cardiomyocytes (NRCMs) were used as in vitro models. We observed that during HFD-induced obesity, Akt2 loss-of-function mitigated lipid accumulation and oxidative stress in the liver and heart tissue. Mechanistically, down-regulation of Akt2 promotes SIRT6 expression in L02 cells and NRCMs, the latter deacetylates SOD2, which promotes SOD2 activity and therefore alleviates oxidative stress-induced injury of hepatocytes and cardiomyocytes. Furthermore, we also proved that AKT2 inhibitor protects hepatocytes and cardiomyocytes from HFD-induced oxidative stress. Therefore, our work prove that AKT2 plays an important role in the regulation of obesity-induced lipid metabolic disorder in the liver and heart. Our study also indicates AKT2 inhibitor as a potential therapy for obesity-induced hepatic and cardiac injury.
A novel parameter decoupling approach of personalised federated learning for image analysis
Authors: Su Ruizheng , Pang Xiongwen , Wang Hui 
Published: May 2023

AbstractGiven the importance of privacy protection in databases and other institutions, federated learning (FL) is used to benefit training machine learning models based on these decentralised and private data so as to address the growing vision tasks. However, for federated learning, statistical heterogeneity continues to be a major problem. Recently, plenty of personalised federated learning methods have been explored to solve the problem of statistical heterogeneity. The usage of trained base layers and the effect of feature extraction in personalised layers, however, are hardly considered in those methods that employ the learning personalised models approach. To address the problem of the statistical heterogeneity in image analysis, PCCFED, a personalised federated learning method utilizing the strategy of parameter decoupling is proposed. It should be emphasised that the authors’ personalised federated learning method decouples the personalised (P) layers into a connecting (C) layer and classifier (C) layer in order to enhance the effectiveness of feature learning for personalised layers. Further, an approach is proposed to fully use the base layers to adapt a personalised model based on the newly admitted institution's dataset through meta‐transfer. The performance of the proposed PCCFED on three datasets is evaluated under the practical non‐independent and identically distributed (non‐IID) setting. Extensive experiments demonstrate that compared with baseline methods, the proposed framework achieves the best performance in federated learning and fine‐tuning. Through FL, the investigation reveals a method to reduce statistical heterogeneity while protecting the institutions' privacy.
Few‐shot logo detection
Authors: Hou Sujuan , Liu Wenjie , Karim Awudu , Jia Zhixiang , Jia Weikuan , Zheng Yuanjie 
Published: May 2023

AbstractThe proliferation of deep learning has driven research into deep learning‐based logo detection, which usually needs a large number of annotated data to train the model. However, due to the occasional appearance of new brands or the high cost of annotation, the number of training data is limited. Against this backdrop, the authors adapt the few‐shot object detection into logo detection, and thus present a cutting‐edge method called Double Classification Head (DCH) for Few‐Shot Logo Detection (DCH‐FSLogo), which aims at detecting the unseen logo classes using few annotated data. Unlike the traditional few‐shot detection, some logo objects are similar to their backgrounds and have diverse shapes as well. For this reason, the authors adopt balanced feature pyramid and deformable Region of Interest pooling in DCH‐FSLogo, this enhances the feature extraction capability and adapts to the different logo shapes. In addition, we introduce the DCH for few‐shot logo detection to detect logo objects using few annotated data. Specifically, we use an extra classification head for the base classes to ease the influence from the novel classes. The experimental results on four datasets, namely: FlickrLogos‐32, FoodLogoDet‐1500‐100, LogoDet‐3K‐100 and QMUL‐OpenLogo‐100, demonstrate that our method achieves better performance.
Interferometric synthetic aperture sonar large scale simulated data benchmark of a ship wreck
Authors: Thomas Benjamin W. , Hunter Alan J. 
Published: May 2023

AbstractInterferometric synthetic aperture sonar (InSAS) systems produce high resolution seafloor imagery and 3‐D bathymetry by exploiting the phase differences between image pairs formed from data collected by vertically separated arrays. This process is non‐trivial due to the inherent ambiguity of interferometric phase estimates, and the effect of layover, where the response of multiple scatterers with different positions are mapped onto the same pixel during imaging. These effects are particularly problematic for complex scenes with strong bathymetry, such as ship wrecks. This is an unsolved problem and improved algorithms for InSAS bathymetry estimation are needed. However, developing and assessing such algorithms using data from fielded InSAS systems is difficult because of a lack of accurate ground truth for the platform motion and the true 3‐D shape of the scene. This paper presents an openly available synthetic data set as an alternative to field‐collected data for use by InSAS algorithm developers. The dataset is derived from a high‐resolution 3‐D photogrammetry scan of the SS Thistlegorm wreck. It was produced by a point‐based diffraction model using parameters similar to the Minehunting UUV for Shallow water Covert Littoral Expeditions (MUSCLE) InSAS.
A new three winding coupled inductors high step‐up DC–DC converter with low input current ripple
Authors: Vesali Mahmood 
Published: May 2023

AbstractA new high step‐up DC–DC converter is proposed in this study. In the proposed converter with voltage lift technique and coupled inductors (CIs) a high voltage gain is achieved. Although the proposed converter has coupled inductors, the input current is continuous and the input current ripple is low. The proposed converter has only one switch and does not have any auxiliary switch, in which the control of the switch is easy. Soft switching condition is presented for the switch in the converter as zero current switching (ZCS) for turning on instant and zero voltage switching (ZVS) for turning off instant, in which the efficiency is increased. For all diodes expect two diodes in the converter ZCS condition is provided when diodes turn off that reverse recovery problem is solved for these diodes. The proposed converter is fully analyzed and described operation of it. To confirm theoretical analysis, 300 W of the proposed converter is implemented and tested, for which in full load an efficiency of 96.5% is achieved.
The diffuse radio emission in the high-redshift cluster PSZ2 G091.83+26.11: Total intensity and polarisation analysis with Very Large Array 1–4 GHz observations
Authors: Di Gennaro G. , Brüggen M. , van Weeren R. J. , Simionescu A. , Brunetti G. , Cassano R. , Forman W. R. , Hoeft M. , Ignesti A. , Röttgering H. J. A. , Shimwell T. W. 
Published: May 2023

Context. Diffuse radio emission in galaxy clusters, namely radio halos and radio relics, is usually associated with merger events. Despite the tremendous advances in observations in the last decades, the particle (re-)acceleration and magnetic field amplification mechanisms and the connection with the stage and geometry of the cluster merger are still uncertain.
Aims. In this paper, we present the peculiar case of PSZ2 G091.83+26.11 at z = 0.822. This cluster hosts a megaparsec-scale radio halo and an elongated radio source whose morphology resembles that of a radio relic. However, the location of this diffuse radio source with respect to the intracluster medium (ICM) distribution and to the cluster centre is not consistent with a simple merger scenario.
Methods. We use Karl Jansky Very Large Array data at 1–4 GHz to investigate the spectral and polarisation properties of the diffuse radio emission. We combine these data with previously published data from the Low Frequency Array (LOFAR) in the 120–168 MHz band and from the upgraded Giant Metrewave Radio Telescope (uGMRT) at 250–500 and 550–900 MHz. Finally, we complement the radio data with Chandra X-ray observations in order to compare the thermal and non-thermal emission of the cluster.
Results. The elongated radio emission east of the cluster is visible up to 3.0 GHz and has an integrated spectral index of α144 MHz3.0 GHz = −1.24 ± 0.03, with a steepening from −0.89 ± 0.03 to −1.39 ± 0.03. These values correspond to Mach numbers ℳradio, int = 3.0 ± 0.19 and ℳradio, inj = 2.48 ± 0.15. Chandra data revealed a surface brightness discontinuity at the location of the radio source with a compression factor of C = 2.22 −0.30+0.39 (i.e. MXray = 1.93−0.32+0.42). We also found that the source is polarised at GHz frequencies. Using QU-fitting, we estimate an intrinsic polarisation fraction of p0 ∼ 0.2, a Rotation Measure of ∼50 rad m−2 (including the Galactic contribution), and an external depolarisation of σRM ∼ 60 rad m−2. The polarisation B-vectors are aligned with the major axis of the source, suggesting magnetic field compression. Hence, we classify this source as a radio relic. Finally, we found a trend consistent with a linear or super-linear correlation between the non-thermal and thermal emission.
Conclusions. We propose an off-axis merger and/or multiple merger events to explain the position and orientation of the relic with the respect to the ICM emission. Given the properties of the radio relic, we speculate that PSZ2 G091.83+26.11 is in a fairly young merger state.
Alte Drogen – neue Erkenntnisse? Neue Strategien zur
adjuvanten Behandlung von Harnwegsinfekten mit Schachtelhalmkraut
Authors: Mo Boris , Hensel Andreas 
Published: May 2023

ZUSAMMENFASSUNGTamm-Horsfall-Protein (syn. THP, Uromodulin) ist ein im distalen Tubulus der
Niere sekretiertes Protein, welches in der Lage ist, uropathogene E. coli
zu binden und somit deren Ausscheidung zu verbessern und die
Pathogen-Wirt-Interaktion zu reduzieren. Die Erhöhung der Sekretion von
THP durch spezielle Induktoren stellt eine neue und innovative Therapiestrategie
zur Prophylaxe und/oder Behandlung von Harnwegsinfekten dar.In einer biomedizinischen Studie mit n=10 Probanden wurde der Einfluss
eines Schachtelhalmkraut-Trockenextraktes (DEV 4–7:1, Auszugsmittel
Wasser) aus Equisetum arvense L. nach siebentägiger Einnahme auf
die THP-Sekretion untersucht. Die jeweilige Tagesdosis des Extraktes
(1,30 g) entspricht 7,2 g Droge und somit der
Dosierungsempfehlung des HMPC. Die Quantifizierung der THP-Konzentrationen in
den Einzelproben und in gepooltem Urin erfolgte aus den an den Studientagen 0,
3, 6 und 8 gesammelten morgendlichen Mittelstrahlurinen mittels validiertem
ELISA. Zusätzlich wurden die Elektrolyte in allen Urinproben sowie der
Kreatinin-Gehalt quantifiziert. Routineparameter wurden mittels Urinteststreifen
bestimmt.Das THP/Kreatinin [µg/mg]-Verhältnis (=
THP-Ausscheidungsrate) unter der Anwendung von Schachtelhalmextrakt zeigte
signifikante Steigerungen über die jeweilige Anwendungsdauer (bis zu
400%, bezogen auf den Ausgangswert des Tag-0-Urins). Ebenfalls zeigte
sich eine diuretische Wirkung, die über die erniedrigte
Osmolarität und die erhöhte Elektrolytausscheidung
(Na+, Cl–, Ca2+
sowie Silicium-Derivate) erkennbar war. Weiterhin wurde der Einfluss der
Urinproben im ex-vivo-Assay auf die Adhäsion von UPEC (Stamm
NU14) auf humane T24-Blasenzellen untersucht. Dabei zeigte sich, dass die
relative bakterielle Adhäsion an die Wirtszellen im Laufe der
Schachtelhalmbehandlung signifikant abnahm. Die Hemmung der bakteriellen
Adhäsion korreliert sehr gut mit der THP-Zunahme in den jeweiligen
Urinproben. Der über LC-MS vollständig charakterisierte
Schachtelhalmextrakt zeigte selbst keine anti-adhäsiven Eigenschaften,
sodass daraus zurückgeschlossen werden kann, dass entweder die renale
Stimulation von THP oder die induzierte Diurese zu einer Verringerung der
bakteriellen Adhäsion führt. Die vorliegenden Untersuchungen
könnten dazu dienen, die traditionelle Verwendung von Ackerschachtelhalm
bei unkomplizierten Harnwegsinfektionen zu rationalisieren.
Dynamic orbital hybridization triggered spin-disorder renormalization via super-exchange interaction for oxygen evolution reaction
Authors: Huang Peilin , Meng Ming , Zhou Gang , Wang Peifang , Wei Wenxian , Li Hao , Huang Rong , Liu Fuchi , Liu Lizhe 
Published: May 2023

The oxygen evolution reaction (OER) underpins many aspects of energy storage and conversion in modern industry and technology, but which still be suffering from the dilemma of sluggish reaction kinetics and poor electrochemical performance. Different from the viewpoint of nanostructuring, this work focuses on an intriguing dynamic orbital hybridization approach to renormalize the disordering spin configuration in porous noble-metal–free metal–organic frameworks (MOFs) to accelerate the spin-dependent reaction kinetics in OER. Herein, we propose an extraordinary super-exchange interaction to reconfigure the domain direction of spin nets at porous MOFs through temporarily bonding with dynamic magnetic ions in electrolytes under alternating electromagnetic field stimulation, in which the spin renormalization from disordering low-spin state to high-spin state facilitates rapid water dissociation and optimal carrier migration, leading to a spin-dependent reaction pathway. Therefore, the spin-renormalized MOFs demonstrate a mass activity of 2,095.1 A g
metal
−1
at an overpotential of 0.33 V, which is about 5.9 time of pristine ones. Our findings provide a insight into reconfiguring spin-related catalysts with ordering domain directions to accelerate the oxygen reaction kinetics.