bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation on the behavior of flow and aerodynamic noise generated around the tandem seal-vibrissa-shaped cylinder
Authors: Zhu Jianyue , Lu Yanhong , Jia Qing , Xia Chao , Chu Shijun
Published: November 2023

Through comparing with the tandem circular and elliptic cylinders with the same characteristic dimensions, the behavior of flow and flow-induced noise generated around the tandem seal-vibrissa-shaped cylinder is studied based on delayed detached-eddy simulation model and acoustic analogy approach. The co-shedding pattern of flow developed around the tandem cylindrical-like bars is investigated. The spatial modes, mode energy, and mode coefficients of turbulent flow around the geometries are analyzed through spectral proper orthogonal decomposition. Results show that the lift fluctuations of downstream bar are stronger than those of upstream bar, and more aerodynamic noise is radiated from the downstream bar than from the upstream bar. The alternative arrangement of nodal and saddle planes of seal-vibrissa-shaped cylinder introduces three-dimensional flow separations and suppresses the shear layer interactions, inhibiting the regular vortex shedding of Kármán vortex street occurring in the tandem cylinder wake. The reversed vortex shedding generated by two adjacent saddle surfaces in the wake of seal-vibrissa-shaped cylinder balances the lateral force and mitigates the lift fluctuations greatly, thereafter reduces the aerodynamic noise generated by wall pressure fluctuations introduced by unsteady fluctuating forces exerting on the surfaces of geometries. Compared to the tandem circular and elliptic cylinders, the good noise reduction effect with sound pressure level reduced at main frequency range has been achieved from the tandem seal-vibrissa-shaped cylinder. The calculated spectra and amplitude levels of aerodynamic noise agree well with the experimental measurements from the anechoic wind tunnel, verifying the accuracy of the numerical simulations.
Twin bi-component drops' evaporation in an acoustic field: The amplitude influence
Authors: Kureshee Aadil , Mandal Deepak Kumar , Narayanan S.
Published: November 2023

The study explores twin bi-component drop evaporation at various acoustic frequencies and amplitudes. The drops have a fixed central spacing. The acoustic streaming around the drops varies with frequency and amplitude. The streaming rises with the amplitude at a given frequency. The acoustics push the outer flow away from the drop. Furthermore, the flow transforms from horizontal to vertical at higher amplitudes, indicating a rise in the outer flow. Correspondingly, the drops' internal circulation and evaporation rise. The maximum evaporation is observed at higher amplitudes and lower frequencies due to intense streaming. The intense streaming accelerates the circulation, forcing the oscillatory circulation to be steadier. In contrast, the circulation is unsteady for lower amplitudes and higher frequencies. The steady circulation escalates the convective current inside the drops and boosts the evaporation rate. An empirical expression is developed to predict the outer flow velocity and evaporation rate at various amplitudes for any twin bi-component drops under diverse acoustic conditions. The study's novelty lies in demonstrating how the amplitude plays a crucial role in modifying the outer flow and internal circulation to elevate the evaporation rate despite frequency.
The reciprocating and bipolar non-Hermitian skin effect engineered by spin–orbit coupling
Authors: Jiang Wen-Cheng , Li Jian , Li Qing-Xu , Zhu Jia-Ji
Published: November 2023

We theoretically study a one-dimensional non-Hermitian Su–Schrieffer–Heeger model with an imaginary gauge field and spin–orbit coupling. We find that, under open boundary conditions, the dispersions possess the reciprocating real–complex–real transitions with increasing the strength of spin–orbit coupling. Correspondingly, the bulk energy eigenstates exhibit a reciprocating non-Hermitian skin effect. This mechanism can be characterized by the generalized Brillouin zone moduli, which approaches zero or infinity at the transition points. We further demonstrate the non-zero winding number inside the loops of generalized Brillouin zone when the strength of intra-cell spin–orbit coupling is larger than the inter-cell one, which results in the bipolar non-Hermitian skin effect. As the intra-cell and inter-cell spin–orbit coupling strength becomes comparable, the bipolar non-Hermitian skin effect degenerates to the conventional non-Hermitian skin effect. Our work may pave the way for the non-Hermitian optoelectronic devices utilizing the reciprocating non-Hermitian skin effect and the bipolar non-Hermitian skin effect by engineering the spin–orbit coupling.
Growth and distribution characteristics of trapped air bubbles in ice slices
Authors: Shao Keke , Song Mengjie , Zhang Xuan , Zhang Long
Published: November 2023

Icing is a complex phase change process that is widespread in nature and industry and may have a number of negative effects. During the freezing of water into ice, air bubbles are often trapped in ice and affect the physical properties of the ice. To control the icing process, it is necessary to study these air bubbles in ice. Here, an experimental setup is built to study the growth and distribution characteristics of trapped air bubbles. The results show that the critical freezing rates for the transitions from the egg-shaped bubble region to the egg-/needle-shaped bubble region and from the egg-/needle-shaped bubble region to needle-shaped region are 22.45 ± 3.24 and 12.64 ± 1.65 μm/s, respectively. A mathematical model that can predict bubble growth is obtained by coupling the gas diffusion equation, Henry's law, and the Young–Laplace equation. The model shows that both the maximum width of the bubble and the distance between adjacent bubbles mainly depend on the freezing rate and are proportional to the inverse of the second power of the freezing rate, meaning that the maximum width and the distance gradually increase as the freezing rate decreases. These results contribute to a better understanding of icing mechanisms and inform the optimization of anti-icing and deicing methods.
Impinging shear layer instability in over-expanded nozzle dynamics
Authors: Tarsia Morisco C. , Robinet J.-C. , Herpe J. , Saucereau D.
Published: November 2023

When rocket engine nozzles operate at a high degree of over-expansion, an internal flow separation occurs with a strong unsteady shock–wave boundary layer interaction. The global dynamics results in a low-frequency mode, which is associated with the shock displacement, and a high-frequency mode, which is correlated with the shear layer–boundary layer interaction. While the mechanism responsible for the low-frequency oscillation is known, the one in charge of the high-frequency unsteadiness is not yet clear. The scope of this paper is to provide a physical explanation for this mechanism. To do that, a delayed detached eddy simulation is used to numerically reproduce the flow in the case of a sub-scale cold-gas truncated ideal contour nozzle. The obtained results are successfully compared to the experiments and confirm the presence of two non-axisymmetric wall pressure signatures at Strouhal numbers St=fDj/Uj≃0.2 and 0.3 with different azimuthal selections. To reveal the origin of such modes, a power spectral density analysis is performed in the separated region. The analysis shows that both modes originate from the external shear layer and behave as “twins” in the separated region. The reason is that both modes are two sides of the same impinging shear layer instability: the acoustic mode propagates with the sound velocity, while the hydrodynamic one propagates with the supersonic shear layer velocity. In this context, the resulting self-sustained dynamics may be due to an acoustic–hydrodynamic feedback loop involving the impinging shear layer instability of the external supersonic shear layer and the separated region.
Levenberg–Marquardt neural network-based intelligent computation for the non-Newtonian polymer during forward roll coating
Authors: Ali Fateh , Hou Yanren , Feng Xinlong , Zahid M. , Ali Muhammad Usman , Pongsumpun Puntani
Published: November 2023

Scientists and researchers widely recognize the effectiveness of artificial intelligence (AI)-based machine learning and intelligent computing solvers, demonstrating qualities such as resilience, robustness, stability, and rapid convergence. One particularly significant and rapidly growing field within AI is artificial neural networks. This research uses a supervised neural network model based on Levenberg–Marquardt backpropagation (LMB-SNNs) to examine the Sisko fluid model for the forward roll coating process (SFM-FRCP). A suitable transformation is applied to the partial differential equations based SFM-FRCP mathematical model, resulting in a set of nonlinear ordinary differential equations. The perturbation method has been used to find the analytical solutions for the velocity profile, pressure gradient, and pressure profile. A dataset for varying the pertinent parameters is generated, and the LMB-SNNs technique has been used to estimate the velocity profile, pressure gradient, and pressure profile behavior during FRCP for numerous scenarios. The numerical solution for SFM-FRCP in different scenarios, such as the validation, training, and testing procedures of LMB-SNNs, is carried out. Moreover, the state transition index, fitness outline, mean square error, histogram error, and regression presentation also endorse the strength and reliability of the solver LMB-SNNs for SFM-FRCP. The comparative analyses and performance studies through outputs of regression drawings, absolute error, and error histograms validate the effectiveness of the suggested solver LMB-SNNs. The method's precision is verified by the closest numerical outputs of both built and dataset values with similar levels 10−11–10−14. Furthermore, it has been observed that as the non-Newtonian parameter increases, the fluid velocity decreases. The research work carried out in this paper is original and fills a gap in the existing research by showing the rheological properties of the Sisko fluid model and the implementation of the LMB-SNNs during the FRCP.
Effects of orthography and cognate status on second language Spanish lexical encoding
Authors: Farrell Victoria , Daidone Danielle
Published: November 2023

This study examined the accuracy of English-speaking learners of Spanish in storing L2 sounds within cognates and
noncognates, specifically in words containing 〈g〉 and 〈h〉, which have differing cross-linguistic phoneme-grapheme
correspondences. In the first task, participants heard Spanish words with target-like pronunciations of 〈g〉 and 〈h〉 or
inaccurate pronunciations with an English-like phonemic substitution for these graphemes, and they decided whether or not they
were words. The second task had participants decide between the two pronunciations of each Spanish word and select the accurate
pronunciation. The findings in both tasks showed that for L2 learners, 〈h〉 cognate words had less accurate phonological
representations compared to all other conditions, possibly due to the greater consistency in phoneme-grapheme correspondence for
〈h〉 in English. These results show that cognate status and orthographic (in)congruity interact to influence the accuracy of
L2 lexical encoding.
Comment on ‘Revisiting the probe and enclosure methods’
Authors: Sini Mourad
Published: November 2023

In the recent manuscript (Ikehata 2022 Inverse Problems
38 075009), the author made some comments on our previous work (Sini and Yoshida 2012 Inverse Problems
28 055013) saying that few arguments in the proof of lemma 3.5 might be incomplete for

C

0
,
1

-regular domains. In this note, we reply to his comments by showing that, for C
1-regular domains, those arguments are correct.
Nonlocal effective medium theory for phononic temporal metamaterials
Authors: Wang Neng , Feng Fanghu , Wang Guo Ping
Published: November 2023

We have developed a nonlocal effective medium theory (EMT) for phononic temporal metamaterials using the multiscale technique. Our EMT yields closed-form expressions for effective constitutive parameters and reveals these materials as reciprocal media with symmetric band dispersion. Even without spatial symmetry breaking, nonzero Willis coupling coefficients emerge with time modulation and broken time-reversal symmetry, when the nonlocal effect is taken into account. Compared to the local EMT, our nonlocal version is more accurate for calculating the bulk band at high wavenumbers and essential for understanding nonlocal effects at temporal boundaries. This nonlocal EMT can be a valuable tool for studying and designing phononic temporal metamaterials beyond the long-wavelength limit.
Periostin-targeted SDSSD peptide decorated calcium phosphate nanocomposites incorporation with simvastatin for osteoporosis treatment
Authors: Pan Zian , Zhang Zhen , Deng Xiongwei , Hu Fanqi , Jia Fan , Lu Jianqing , Zhang Xuesong , Yang Xiaoqing , Gao Yujuan , Wang Xuan , Cui Xinyue , Xu Chenlu , Wu Yan
Published: November 2023

The limited options of anabolic drugs restrict their application potential in osteoporosis treatment, despite their theoretical superiority in therapeutic efficacy over antiresorptive drugs. As a prevailing strategy, nano-delivery systems could offer a wider choice of anabolic drugs. In this study, calcium phosphate nanocomposites incorporated with simvastatin (Sim) with periostin-targeting ability were designed and prepared for osteoporosis treatment. Carboxymethyl dextran (CMD) as an anionic and hydrophilic dextran derivative was used to stabilize CaP. In addition, periosteum-targeted peptide (SDSSD) was further grafted on CMD to achieve the bone targeting function. In a one-step coordination assembly strategy, hydrophobic anabolic agent Sim and SDSSD-CMD graft (SDSSD-CMD) were incorporated into the CaP nanoparticles forming SDSSD@CaP/Sim nanocomposites. The resulting SDSSD@CaP/Sim possesses uniform size, great short-term stability and excellent biocompatibility. Moreover, SDSSD@CaP/Sim exhibited a reduced release rate of Sim and showed slow-release behaviour. As anticipated, the nanocomposites exhibited bone bonding capacity in both cellular and animal studies. Besides, SDSSD@CaP/Sim achieved obviously enhanced osteoporosis treatment effect compared to direct injection of Sim in vivo. Therefore, our findings highlight the potential of SDSSD-incorporated and CaP-based nanocomposites as a viable strategy to enhance the therapeutic efficacy of anabolic drugs for osteoporosis treatment.
Mitigating misalignment in MRI-to-CT synthesis for improved synthetic CT generation: an iterative refinement and knowledge distillation approach
Authors: Zhou Leyuan , Ni Xinye , Kong Yan , Zeng Haibin , Xu Muchen , Zhou Juying , Wang Qingxin , Liu Cong
Published: November 2023

Objective.Deep learning has shown promise in generating synthetic CT (sCT) from magnetic resonance imaging (MRI). However, the misalignment between MRIs and CTs has not been adequately addressed, leading to reduced prediction accuracy and potential harm to patients due to the generative adversarial network (GAN)hallucination phenomenon. This work proposes a novel approach to mitigate misalignment and improve sCT generation.Approach.Our approach has two stages: iterative refinement and knowledge distillation. First, we iteratively refine registration and synthesis by leveraging their complementary nature. In each iteration, we register CT to the sCT from the previous iteration, generating a more aligned deformed CT (dCT). We train a new model on the refined 〈dCT, MRI〉 pairs to enhance synthesis. Second, we distill knowledge by creating a target CT (tCT) that combines sCT and dCT images from the previous iterations. This further improves alignment beyond the individual sCT and dCT images. We train a new model with the 〈tCT, MRI〉 pairs to transfer insights from multiple models into this final knowledgeable model.Main results.Our method outperformed conditional GANs on 48 head and neck cancer patients. It reduced hallucinations and improved accuracy in geometry (3% ↑ Dice), intensity (16.7% ↓ MAE), and dosimetry (1% ↑γ3%3mm). It also achieved <1% relative dose difference for specific dose volume histogram points.Significance.This pioneering approach for addressing misalignment shows promising performance in MRI-to-CT synthesis for MRI-only planning. It could be applied to other modalities like cone beam computed tomography and tasks such as organ contouring.
PCA and logistic regression in 2-[18F]FDG PET neuroimaging as an interpretable and diagnostic tool for Alzheimer’s disease
Authors: Gonçalves de Oliveira Carlos Eduardo , de Araújo Whemberton Martins , de Jesus Teixeira Ana Beatriz Marinho , Gonçalves Gustavo Lopes , Itikawa Emerson Nobuyuki ,   For the Alzheimer’s Disease Neuroimaging Initiative
Published: November 2023

Objective. to develop an optimization and training pipeline for a classification model based on principal component analysis and logistic regression using neuroimages from PET with 2-[18F]fluoro-2-deoxy-D-glucose (FDG PET) for the diagnosis of Alzheimer’s disease (AD). Approach. as training data, 200 FDG PET neuroimages were used, 100 from the group of patients with AD and 100 from the group of cognitively normal subjects (CN), downloaded from the repository of the Alzheimer’s Disease Neuroimaging Initiative (ADNI). Regularization methods L1 and L2 were tested and their respective strength varied by the hyperparameter C. Once the best combination of hyperparameters was determined, it was used to train the final classification model, which was then applied to test data, consisting of 192 FDG PET neuroimages, 100 from subjects with no evidence of AD (nAD) and 92 from the AD group, obtained at the Centro de Diagnóstico por Imagem (CDI). Main results. the best combination of hyperparameters was L1 regularization and C ≈ 0.316. The final results on test data were accuracy = 88.54%, recall = 90.22%, precision = 86.46% and AUC = 94.75%, indicating that there was a good generalization to neuroimages outside the training set. Adjusting each principal component by its respective weight, an interpretable image was obtained that represents the regions of greater or lesser probability for AD given high voxel intensities. The resulting image matches what is expected by the pathophysiology of AD. Significance. our classification model was trained on publicly available and robust data and tested, with good results, on clinical routine data. Our study shows that it serves as a powerful and interpretable tool capable of assisting in the diagnosis of AD in the possession of FDG PET neuroimages. The relationship between classification model output scores and AD progression can and should be explored in future studies.
Integration of vertically-aligned carbon nanotubes with superconducting nanowire single photon detectors
Authors: Rampini D S , Yung C S , Oripov B G , Woods S , Lehman J , Nam S W , McCaughan A N
Published: November 2023

We report on initial fabrication efforts in the integration of superconducting nanowire single-photon detectors (SNSPDs) with vertically aligned carbon nanotubes (VACNTs) with the goal of creating a wideband single-photon detector. SNSPDs provide high detection efficiencies and low dark count rates, while the VACNTs are excellent broadband optical absorbers. Combining these technologies could potentially enable the development of highly sensitive and versatile optical sensors for a variety of applications, such as spectroscopy, optical communication, and imaging in light starved environments. We developed two fabrication processes for the integration of VACNTs on SNSPDs. The first involves capping the SNSPDs with a protective layer and growing the VACNTs directly above nanowires. Thermal and electrical characterizations of the devices demonstrated a degradation of the superconducting qualities of the SNSPDs. The second process involved suspending the SNSPDs on a thin membrane via a backside etch, where VACNTs were then grown on the backside of the membranes below the nanowires. The membrane style devices showed no degradation in the superconducting properties of the nanowires. Measurements of the membrane style devices before and after the VACNT growth display similar superconducting properties and photon count rates.
Highly responsive self-driven broadband hybrid photodetector with high detectivity and on/off ratio based on Hibiscus sabdariffa
Authors: Yuca Hafize , Karakaya Songül , Yıldırım Fatma , İncekara Ümit , Aydoğan Şakir
Published: November 2023

A Hibiscus sabdariffa (HBS)/n-Si hybrid photodetector was fabricated and it was observed that the device has a high rectification ratio of 10.2 × 104 in dark and superior photoresponse at different intensities of visible light in addition to UV and IR lights. The non-linear response to light intensity in visible light was attributed to phase change effects and the presence of traps, which are the result of the hibiscus sabdariffa’ response to light. The responsivity at 850 nm reaches 1.16 A W−1 (at V = −2.0 V) and a high specific detectivity of 2.0 × 1012 Jones (for self-driven mode) with an external quantum efficiency of 411% was obtained. In addition, in self-driven mode of UV and IR lights, the highest on/off ratio and NPDR values reached ∼105 and ∼109 W−1 levels, respectively. Moreover, HBS/n-Si hybrid broad-band photodetector showed long-term stability (40 days) without encapsulation both in the dark and under the light.
A novel time domain analysis of the modes perturbed by a lossy material in a cavity
Authors: Erden Fatih
Published: November 2023

This study delves into the intricate dynamics of time-domain electromagnetic phenomena within an irregular rectangular cavity perturbed by a lossy conducting body. Focusing on coupled degenerate (singular) TM and TE solenoidal modes, the analysis reveals eigenfrequency splitting due to irregularities like a lossy body. By employing an upgraded version of the Evolutionary Approach to Electromagnetics with novel Maxwell’s equations in SI units, our explicit solution adheres to the causality principle. This united dynamic system exhibits both forced and free oscillations, initiated by a finite duration signal. The study highlights the dual nature of oscillations: forced oscillations excited by the signal and subsequent free oscillations. In irregular cavities, the eigenvalues undergo splitting, signifying a dissipative dynamic system. Our work significantly advances the understanding of these complex electromagnetic systems, demonstrating practical relevance in electromagnetics and offering a novel perspective on irregular cavity dynamics.
Point-symmetry in SNR G1.9+0.3: A Supernova that Destroyed its Planetary Nebula Progenitor
Authors: Soker Noam
Published: November 2023

I analyze a new X-ray image of the youngest supernova remnant (SNR) in the Galaxy, which is the type Ia SNR G1.9+0.3, and reveal a very clear point-symmetrical structure. Since explosion models of type Ia supernovae (SNe Ia) do not form such morphologies, the point-symmetrical morphology must come from the circumstellar material (CSM) into which the ejecta expands. The large-scale point-symmetry that I identify and the known substantial deceleration of the ejecta of SNR G1.9+0.3 suggest a relatively massive CSM of ≳1M
⊙. I argue that the most likely explanation is the explosion of this SN Ia into a planetary nebula. The scenario that predicts a large fraction of SN Ia inside PNe (SNIPs) is the core degenerate scenario. Other SN Ia scenarios might lead to only a very small fraction of SNIPs or none at all.
A Sequence on the Maximum Eigenvalue of a Nonnegative Matrix
Authors: Zhong Qin
Published: November 2023

For an irreducible matrix with nonnegative entries, a sequence is constructed on the matrix trace. And we prove the convergence of the sequence in two cases when the irreducible matrix with nonnegative entries is a primitive matrix and a non-primitive matrix.
Data science in wind energy: a case study for Norwegian offshore wind
Authors: Chen Hao , Birkelund Yngve , Zhang Qixia
Published: November 2023

In the digital and green transitions, rapidly growing renewable energies are accumulating more and more data. Big data gives room to apply emerging data science to solve challenges in the energy sector. Offshore wind power receives accelerating attention due to its sufficient resources and cleanness. This paper uses data science, including statistical analysis and machine learning, to systematically analyse three coastal wind sites in Norway. The results show that although Norway possesses ample offshore resources, its development could be improved by natural, technical, and economic challenges that can be addressed with the help of data science. Technically, the statistical attributes and forecasting intricacy of offshore wind resources differ across various regions of Norway.
Application of EMD combined with wavelet algorithm for filtering slag noise in steel cord conveyor belt
Authors: Sun Guoxin , Zhang Runze , Liu Zejiang , Wu Linfeng , Yu Qihui , Tan Xin
Published: November 2023

This study proposes a noise reduction technique that combines empirical mode decomposition (EMD) with wavelet thresholding to remove noise interference generated by metal slag in the damage signal of steel cord conveyor belts. The initial step involves decomposing the original signal into high-frequency and low-frequency intrinsic mode function (IMF) components using empirical mode decomposition (EMD), guided by the metal slag signal characteristics analysis. The high-frequency noise is filtered away while the low-frequency IMF components are kept intact through the wavelet threshold de-noising technique. The slag noise-containing IMF components are deleted, and the filtered signal and the low-frequency IMF components are utilized for signal reconstruction to provide the optimum noise reduction result. The study demonstrates that this method is more effective in suppressing metal slag noise, environmental noise, and other noise interferences than traditional EMD decomposition noise reduction and wavelet threshold noise reduction methods. This research provides a valuable reference for noise reduction in steel cord conveyor belt detection data.
RF-wave induced CBRAM characteristic modulation specific to sheet-like conductive filaments
Authors: Yin Yifei , Tsukamoto Keito , Hayashi Hitoshi , Nakaoka Toshihiro
Published: November 2023

The shape of conductive filaments in CBRAM is important for resistance switching and conductance modulation, especially in applications like neuromorphic and reservoir computing that use conductance as weight. We report on RF-induced modulation of CBRAM using Ge2Sb3.4Te6.2 with sheet-like filaments and compared it to those with dendritic filaments. RF input below 100 MHz reduced SET and RESET voltages, similar to CBRAM with dendritic filaments, but showed significantly different resistance changes. Repeated RF on/off input gradually increased the resistance of low-resistance state, unlike the dendritic filament CBRAM, where the resistance decreased. The increased resistance suggests RF-induced denser sheet-like filaments. Furthermore, the resistance of the high-resistance state showed a peculiar RF-induced resistance change not observed in dendritic filaments. The resistance decreased during RF input and increased to nine times the initial value when RF was switched off. The results show that the conductance modulation by RF input strongly depends on the filament type.
Solar thermoelectric generator and thermoelectric cooler performance: analysis and comparison using a different shape geometry
Authors: Khalil ALkhadher , Sahnoun Smail , Elhassnaoui Ahmed , Yadir Said , Obbadi Abdellatif , Errami Youssef
Published: November 2023

Thermoelectric devices are one of the technologies used either to generate electricity by applying a temperature difference using thermal energy or as a heating/cooling system by applying an electrical voltage. The number of materials required to produce a product is an important factor in determining its price. Production costs associated with these materials, as well as their availability and quality, play a crucial role in price determination by manufacturers. In this context, a method that employs a uniform volume distribution was implemented. This approach enabled the analysis to focus on other variables, thereby promoting a more precise and relevant evaluation of overall performance. Based on the finite element method, this study investigated the influence of geometric shape, including Rect-leg, Y-leg, Pin-leg and X-leg designs, on the performance of solar thermoelectric generators and thermoelectric coolers. The study was conducted considering the same hot alumina junction surface that receives solar radiation; however, the effective surface, which corresponded to the heat flow area and had a similar area near the exposed surface, varied depending on the chosen leg geometry, thus impacting the heat flux due to the variation in thermal resistance. In the case of a solar thermoelectric generator, the Rect-leg model, having the same effective surface area, presented the lowest heat loss value resulting from convection and radiation in the heat spreader and the hot alumina plate. Under the same conditions, the Y-leg showed the highest value. The Rect-leg design generated, by using thermal and optical concentration, the highest output power of 0.028 and 0.054 W, and efficiency of 3.47% and 4.7%, respectively, whereas the Y-leg generated lower values of 0.006523 and 0.018744 W for power, and 2.83% and 2.71% for efficiency, respectively. In the case of the thermoelectric coolers, the Y-leg generated the highest temperature difference between the hot and cold sides of 67.28 K at an electric current value of 1.8 A, whereas the Rect-leg, Pin-leg and X-leg generated ~66.25, ~67.02 and ~67.19 K at 6.1, 2.7 and 2.6 A.
A Simple and Rapid High-Performance Liquid Chromatography Method for Preparation and Content Detection of the Mainly Numbing Taste Substances of Zanthoxylum bungeanum Maxim
Authors: Wang Zixu , Liu Yue , Sun Guoqing , Yang Liu , Huang Shuai , Chen Lin , Zhou Xianli
Published: November 2023

As the characteristic numbing taste substances, hydroxyl-α-sanshool (HAS) and hydroxyl-β-sanshool (HBS) were considered vital indicators to evaluate the quality of Zanthoxylum bungeanum Maxim. However, it is very difficult to obtain their high-purity monomers individually, as the only difference between HAS and HBS is that C-6 cis-trans isomerism. In our study, a simple and rapid Ag +-HPLC method was developed to pure the standard chemicals of Z. bungeanum with numbing taste, and 1H NMR and 13C NMR were employed to determine the purity and structure. Moreover, an HPLC method was established to determine the content of numbing taste components of 16 varieties of Z. bungeanum from different regions. The analytical methods were validated for accuracy, precision, and linearity, respectively. The validated method was accurate (spiked recoveries 0.94–1.10), precise in terms of peak area (intra-day RSDs <1.25% and inter-day RSDs <1.61%), and linear (r2 ≥ 0.999). It was found that there were significant differences in the content of HAS and HBS among different types of Z. bungeanum, with HAS content ranging from 60.06 ± 1.14 to 164.13 ± 3.28 mg/g and HBS ranging from 7.81 ± 0.36 to 21.11 ± 0.75 mg/g. The RSDs of HAS range were 1.73–3.80% and that of HBS range 2.03–4.73% (RSDs ≤5%), which indicated that the measurements of HAS and HBS were reliable.
Pre-exposure Prophylaxis Use History in People With Antiretroviral Resistance at HIV Diagnosis: Findings From New York City HIV Surveillance and Partner Services, 2015–2022
Authors: Misra Kavita , Huang Jamie S , Udeagu Chi-Chi N , Forgione Lisa , Xia Qiang , Torian Lucia V
Published: November 2023

Background

Drug resistance may be acquired in people starting human immunodeficiency virus (HIV) preexposure prophylaxis (PrEP) during undiagnosed infection. Population-based estimates of PrEP-related resistance are lacking.

Methods

We used New York City surveillance and partner services data to measure the effect of PrEP use (tenofovir disoproxil fumarate/tenofivir alafenamide fumarate with emtricitabine) history on the baseline prevalence of M184I/V mutations in people with HIV diagnosed in 2015–2022. PrEP use was categorized as “recent” (defined as PrEP stopped ≤90 days before diagnosis), “past” (PrEP stopped >90 days before diagnosis), or “no known use.” Resistance-associated mutations were determined using the Stanford algorithm. We used log binomial regression to generate the adjusted relative risk (aRR) of M184I/V by PrEP use history in people with or without acute HIV infection (AHI).

Results

Of 4246 people with newly diagnosed HIV and a genotype obtained within ≤30 days of diagnosis, 560 (13%) had AHI; 136 (3%) reported recent and 124 (35%) past PrEP use; and 98 (2%) harbored M184I/V. In people with AHI, recent PrEP use was associated with a 6 times greater risk of M184I/V than no known use (aRR, 5.86 [95% confidence interval, 2.49–13.77]). Among people without AHI, the risk of M184I/V in recent users was 7 times that in people with no known use (aRR, 7.26 [95% confidence interval, 3.98–13.24]), and in past users, it was 4 times that in those with no known use (4.46 [2.15–9.24]).

Conclusions

PrEP use was strongly associated with baseline M184I/V in New York City, regardless of AHI status. Ordering a nucleic acid test when indicated after assessment of exposure, antiretroviral history, and AHI symptoms can decrease PrEP initiation in people with undetected infection.
Left ventricular mechanical dispersion as a predictor of the need for pacemaker implantation after transcatheter aortic valve implantation: MeDiPace TAVI study
Authors: Kaya Esra , Andresen Kristoffer , Lie Øyvind H , Aaberge Lars , Haugaa Kristina H , Edvardsen Thor , Skulstad Helge
Published: November 2023

Aims

Permanent pacemaker (PM) implantation is common after transcatheter aortic valve implantation (TAVI). Left ventricular mechanical dispersion (MeDi) by speckle tracking echocardiography is a marker of fibrosis that causes alterations in the conduction system. We hypothesized that MeDi can be a predictor of the need for PM implantation after TAVI.

Methods and results

Consecutively, 200 TAVI patients were enrolled. Transthoracic echocardiography and electrocardiography examinations were recorded before TAVI to evaluate global longitudinal strain (GLS), MeDi, and conduction disturbances. PM implantation information was obtained 3 months after TAVI. Patients were stratified into PM or no PM group. Mean age was 80 + 7 years (44% women). Twenty-nine patients (16%) received PM. MeDi, QRS duration, existence of right bundle branch abnormality (RBBB), and first-degree atrioventricular (AV) block were significantly different between groups. MeDi was 57 ± 15 ms and 48 ± 12 ms in PM and no PM groups, respectively (P < 0.001). In multivariate analysis, MeDi predicted the need for PM after TAVI independently of GLS, QRS duration, RBBB, and first-degree AV block [odds ratio (OR): 1.73, 95% confidence interval (CI): 1.22–2.45] with an area under the curve (AUC) of 0.68 in receiver operating characteristic (ROC) curves. Moreover, RBBB was an independent predictor of PM need after TAVI (OR: 8.98, 95% CI: 1.78–45.03). When added to RBBB, MeDi had an incremental predictive value with an AUC of 0.73 in ROC curves (P = 0.01).

Conclusion

MeDi may be used as an echocardiographic functional predictor of the need for PM after TAVI.
Chartist Studies and Malcolm Chase: A Re-appreciation
Authors: Navickas Katrina
Published: November 2023

Malcolm Chase (1957–2020) was the pre-eminent scholar of the Chartist democratic movement, and more broadly, of working-class political and social action in early nineteenth-century Britain. His work in many respects shaped a shift in the study of Chartism within labour and cultural history. Rejecting the inward-looking diversion into the ‘linguistic turn’ of the early 1990s, Chase offered a broader and holistic view of not only what class, political radicalism and the land meant to working-class people, but also how it was a lived experience expressed in action as well as words. This article is a re-appreciation of Chase’s major contribution to the field. It charts the origins and development of Chartist studies, and surveys recent publications, including the wide range of articles published on Chartism in the English Historical Review.
Regional and temporal differences in the associations between cardiovascular disease and its classic risk factors: an analysis of 49 cohorts from 11 European countries
Authors: Reinikainen Jaakko , Kuulasmaa Kari , Oskarsson Viktor , Amouyel Philippe , Biasch Katia , Brenner Hermann , De Ponti Roberto , Donfrancesco Chiara , Drygas Wojciech , Ferrieres Jean , Grassi Guido , Grimsgaard Sameline , Iacoviello Licia , Jousilahti Pekka , Kårhus Line L , Kee Frank , Linneberg Allan , Luksiene Dalia , Mariño Joany , Moitry Marie , Palmieri Luigi , Peters Annette , Piwonska Aleksandra , Quarti-Trevano Fosca , Salomaa Veikko , Sans Susana , Schmidt Carsten Oliver , Schöttker Ben , Söderberg Stefan , Tamosiunas Abdonas , Thorand Barbara , Tunstall-Pedoe Hugh , Vanuzzo Diego , Veronesi Giovanni , Woodward Mark , Lekadir Karim , Niiranen Teemu
Published: November 2023

Aims

The regional and temporal differences in the associations between cardiovascular disease (CVD) and its classic risk factors are unknown. The current study examined these associations in different European regions over a 30-year period.

Methods and results

The study sample comprised 553 818 individuals from 49 cohorts in 11 European countries (baseline: 1982–2012) who were followed up for a maximum of 10 years. Risk factors [sex, smoking, diabetes, non-HDL cholesterol, systolic blood pressure (BP), and body mass index (BMI)] and CVD events (coronary heart disease or stroke) were harmonized across cohorts. Risk factor–outcome associations were analysed using multivariable-adjusted Cox regression models, and differences in associations were assessed using meta-regression. The differences in the risk factor–CVD associations between central Europe, northern Europe, southern Europe, and the UK were generally small. Men had a slightly higher hazard ratio (HR) in southern Europe (P = 0.043 for overall difference), and those with diabetes had a slightly lower HR in central Europe (P = 0.022 for overall difference) compared with the other regions. Of the six CVD risk factors, minor HR decreases per decade were observed for non-HDL cholesterol [7% per mmol/L; 95% confidence interval (CI), 3–10%] and systolic BP (4% per 20 mmHg; 95% CI, 1–8%), while a minor HR increase per decade was observed for BMI (7% per 10 kg/m2; 95% CI, 1–13%).

Conclusion

The results demonstrate that all classic CVD risk factors are still relevant in Europe, irrespective of regional area. Preventive strategies should focus on risk factors with the greatest population attributable risk.
Diversity of Methylobacterium species associated with New Zealand native plants
Authors: Jahan Rowshan , McDonald Ian R
Published: November 2023

Methylobacterium species are abundant colonizers of the phyllosphere due to the availability of methanol, a waste product of pectin metabolism during plant cell division. The phyllosphere is an extreme environment, with a landscape that is heterogeneous and continuously changing as the plant grows and is exposed to high levels of ultraviolet irradiation. Geographically, New Zealand (NZ) has been isolated for over a million years, has a biologically diverse flora, and is considered a biodiversity hotspot, with most native plants being endemic. We therefore hypothesize that the phyllosphere of NZ native plants harbor diverse groups of Methylobacterium species. Leaf imprinting using methanol-supplemented agar medium was used to isolate bacteria, and diversity was determined using ARDRA and 16S rRNA gene sequencing. Methylobacterium species were successfully isolated from the phyllosphere of 18 of the 20 native NZ plant species in this study, and six different species were identified: M. marchantiae, M. mesophilicum, M. adhaesivum, M. komagatae, M. extorquens, and M. phyllosphaerae. Other α, β, and γ-Proteobacteria, Actinomycetes, Bacteroidetes, and Firmicutes were also isolated, highlighting the presence of other potentially novel methanol utilizers within this ecosystem. This study identified that Methylobacterium are abundant members of the NZ phyllosphere, with species diversity and composition dependent on plant species.
Heterogeneity in the progression of retinal pathologies in mice harboring patient mimicking Impg2 mutations
Authors: Williams Brittany N , Draper Adam , Lang Patrick F , Lewis Tylor R , Smith Audrey L , Mayerl Steven J , Rougié Marie , Simon Jeremy M , Arshavsky Vadim Y , Greenwald Scott H , Gamm David M , Pinilla Isabel , Philpot Benjamin D
Published: November 2023

Biallelic mutations in interphotoreceptor matrix proteoglycan 2 (IMPG2) in humans cause retinitis pigmentosa (RP) with early macular involvement, albeit the disease progression varies widely due to genetic heterogeneity and IMPG2 mutation type. There are currently no treatments for IMPG2-RP. To aid preclinical studies toward eventual treatments, there is a need to better understand the progression of disease pathology in appropriate animal models. Toward this goal, we developed mouse models with patient mimicking homozygous frameshift (T807Ter) or missense (Y250C) Impg2 mutations, as well as mice with a homozygous frameshift mutation (Q244Ter) designed to completely prevent IMPG2 protein expression, and characterized the trajectory of their retinal pathologies across postnatal development until late adulthood. We found that the Impg2T807Ter/T807Ter and Impg2Q244Ter/Q244Ter mice exhibited early onset gliosis, impaired photoreceptor outer segment maintenance, appearance of subretinal deposits near the optic disc, disruption of the outer retina, and neurosensorial detachment, whereas the Impg2Y250C/Y250C mice exhibited minimal retinal pathology. These results demonstrate the importance of mutation type in disease progression in IMPG2-RP and provide a toolkit and preclinical data for advancing therapeutic approaches.
Digital technologies, learning capacity of the organization and innovation: EU-wide empirical evidence from a combined dataset
Authors: Greenan Nathalie , Napolitano Silvia
Published: November 2023

This paper investigates the effects of digitalization and organizational practices on innovation in Europe, between 2010 and 2016. We analyze the cross-country and industry differences in firms’ investments and capabilities to adopt and use new technologies and their effects on innovation outputs. Along with traditional drivers of innovation, such as research and development (R&D) expenditure, two composite indicators are constructed. One encompasses direct measures of the adoption and use in enterprises of a set of digital technologies. The other measures the learning capacity of organizations, which captures the use of management tools and organizational practices concerned with the improvement of individual and organizational learning. Product, process, organizational, and marketing innovations are identified as well as their combinations within companies. Empirical evidence is provided by a unique dataset based on the integration at the sector within the country level of European Union (EU)-wide employers’ and employees’ surveys: the Community Innovation Survey (CIS), the Community Information and Communication Technologies (ICT) usage and e-commerce in enterprises survey (Eurostat), and the European Working Conditions Survey (Eurofound). The descriptive evidence shows that Digital technology adoption and use is rapidly growing across Europe, while the Learning capacity of organizations remains stagnant. By contrast, our results from the econometric analysis show that these investments can favor all forms of innovations and that, further, they may show some complementarity. Overall, a mix of product/process innovations and organizational/marketing innovations rests on joint investments in R&D, digital technology adoption and use, and learning capacity of the organization.
Nitrofurantoin resistance as an indicator for multidrug resistance: an assessment of Escherichia coli urinary tract specimens in England, 2015–19
Authors: Guy Rebecca L , Rudman Jamie , Higgins Hannah , Carter Emma , Henderson Katherine L , Demirjian Alicia , Gerver Sarah M
Published: November 2023

Objectives

To determine whether MDR occurs more frequently in nitrofurantoin-resistant Escherichia coli urinary isolates in England, compared with nitrofurantoin-susceptible isolates.

Methods

Using routine E. coli urine isolate antibiotic susceptibility laboratory surveillance data for England, 2015–19 inclusive, the percentage of MDR or XDR phenotype was estimated for nitrofurantoin-susceptible and nitrofurantoin-resistant laboratory-reported urinary tract samples by region, patient sex and age group.

Results

Resistance to nitrofurantoin among E. coli urinary samples decreased slightly year on year from 2.9% in 2015 to 2.3% in 2019. Among E. coli UTIs tested for nitrofurantoin susceptibility and  ≥3 additional antibiotics, the percentage that were MDR was consistently 15%–20% percentage points higher for nitrofurantoin-resistant isolates compared with nitrofurantoin-susceptible isolates. Similarly, the percentage of isolates with an XDR phenotype was higher among nitrofurantoin-resistant versus -susceptible isolates (8.7% versus 1.4%, respectively, in 2019); this disparity was greater in male patients, although variation was seen by age group in both sexes. Regional variation was also noted, with the highest MDR percentage amongst nitrofurantoin-resistant E. coli urinary samples in the London region (36.7% in 2019); the lowest was in the North East (2019: 16.9%).

Conclusions

MDR and XDR phenotypes occur more frequently in nitrofurantoin-resistant E. coli urinary isolates in England, compared with nitrofurantoin-susceptible isolates. However, nitrofurantoin resistance is low (<3%) overall. This latest study provides important insights into trends in nitrofurantoin resistance and MDR, which is of particular concern for patients ≥75 years old and those who are male. It also emphasises geographical heterogeneities within England in nitrofurantoin resistance and MDR.
Dominance of ST131, B2, blaCTX-M-15, and papA-papC-kpsMII-uitA among ESBL Escherichia coli isolated from bloodstream infections in Quito, Ecuador: a 10-year surveillance study (2009–2019)
Authors: Zurita Jeannete , Sevillano Gabriela , Paz y Miño Ariane , Haro Nathalí , Larrea-Álvarez Marco , Alcocer Iliana , Ortega-Paredes David
Published: November 2023

Aims

This study aimed to examine antibiotic resistance and the epidemiology of extended-spectrum β-lactamases (ESBL)-producing Escherichia coli associated with bloodstream infections over a period of 10 years.

Methods and results

Isolates were collected from January 2009 to December 2019 and those testing for E. coli were included. Antibiotic susceptibility was tested using the VITEK® system. Selected isolates were further characterized by amplification of marker genes (virulence traits, phylogroups, and sequence types). A total of 166 ESBL-producing E. coli were recovered. The blaCTX-M-15 allele was the most abundant. Most of the isolates were resistant to ceftriaxone, cefepime, ceftazidime, ampicillin/sulbactam, piperacillin/tazobactam, and ciprofloxacin. No resistance to carbapenems was registered. More than 80% of bacteria were classified as extraintestinal pathogenic E. coli (ExPEC), and the combination of virulence traits:papA-papC-kpsMII-uitA was the most common. Phylogroup B2 was the most prevalent, and bacteria predominantly belonged to ST131.

Conclusions

There was an increase in the ExPEC ESBL-E coli in bloodstream infections and the relationship between the isolates found in these infections during these 10 years.