bluuebunny/crossref_metadata_2025 huggingface dataset:
Prior knowledge-based self-supervised learning for intelligent bearing fault diagnosis with few fault samples
Authors: Wu Ke , Nie Yukang , Wu Jun , Wang Yuanhang
Published: June 2023

Deep learning-based bearing fault diagnosis methods have been developed to learn fault knowledge from massive data. Owing to the deficiency of fault samples and the variability of working conditions, these deep learning-based methods are limited in industrial applications. To address this problem, this study proposes a prior knowledge-based self-supervised learning (PKSSL) method for bearing fault diagnosis. In the PKSSL method, prior diagnostic knowledge is extracted by meta-learning from a few samples. Prior diagnostic knowledge is then utilized to guide the self-supervised learning (SSL) process to reduce reliance on training data. Furthermore, a graph convolutional network is introduced to fuse the information obtained by meta-learning and SSL, which makes the model fully utilize the learned information and improves the accuracy of the fault diagnosis. The effectiveness of the proposed method was validated using two datasets. The results demonstrate that compared to other existing approaches, the proposed method exhibits a strong generalization ability to transfer diagnostic knowledge from artificial damage data to real damage data under varied operating conditions.
Automated defect recognition (ADR) for monitoring industrial components using neural networks with phased array ultrasonic images
Authors: Gantala Thulsiram , P L Sudharsan , Balasubramaniam Krishnan
Published: June 2023

In this paper, we propose a framework to automate the process of defect characterizing for industrial structural component health monitoring by implementing automatic defect recognition (ADR) system. The ADR system consists of a convolutional neural network (CNN) and an edge detection algorithm medial axis transform (MAT). The CNN learns the defect feature space from the training dataset to detect and classify the defect. The MAT algorithm is used upon post-validation of the ADR, and the predicted feature’s edges are extracted to size them. The ADR is trained using the simulation-assisted finite element (FE) simulation datasets consisting of side drilled holes (SDH) and crack defects images. The training datasets are generated by introducing virtual array source aperture (VASA), which is a full matrix capture (FMC) scanning strategy by activating the group of elements in an active aperture with predefined focal laws to form a focused beam at a virtual source in the material. The VASA technique uses multiple virtual sources and active aperture positions in a given transducer, which are determined using the Poisson point process. The ultrasound beam is excited in sequence on each virtual source, and the reflected wave is recoded using all the transducers in the array to create FMC A-scans signals. The total focusing method (TFM) technique is a postprocessing algorithm implemented on the FMC signal to generate an image. A large quantity of training datasets is created for each defect by modeling various FE models with varying defect morphology. To create nearly close to experimental images, the experimental noise is introduced in the simulated images. The three separate ADR systems are trained with individual defects class and combined defects. The effectiveness of the trained ADR system is validated by conducting experiments on the plates with laboratory-made SDH and crack defects, the casting components, and weldments with unknown defect types and sizes. The mAP of ADR training is 82%, and the F1-score on testing image classification is 89%. The ADR system could detect and size the smallest defect is 0.219 mm, which is λ

L
/5.
Arresting the surface oxidation kinetics of bilayer 1T′-MoTe2 by sulphur passivation
Authors: Chandran Yadu , Thakur Deepa , Raju Naik B , Balakrishnan Viswanath
Published: June 2023

MoTe2 garnered much attention among 2D materials due to stable polymorphs with distinctive structural and electronic properties. Among the polymorphs, 1T′-MoTe2 in bulk form is type—II Weyl semimetal while, in monolayer form is a quantum spin Hall insulator. Thus, it is suitable for a wide variety of applications. Nevertheless, 1T′-MoTe2 degrades within a few hours when exposed to the atmosphere and causes hindrances in device fabrication. Here the degradation kinetics of CVD-synthesized 1T′-MoTe2 was investigated using Raman spectroscopy, XPS, and microscopic characterizations. The degradation rate of as-grown 1T′-MoTe2 obtained was 9.2 × 10−3 min−1. Further, we prevented the degradation of 1T′-MoTe2 by introducing a thin coating of S that encapsulates the flakes. 1T′-MoTe2 flakes showed stability for several days when covered using sulphur, indicating 25 times enhanced structural stability.
Inverse design of plasmonic nanoantenna using generative adversarial network
Authors: Bao Qiwen , Zhang Dasen , Liu Xianjin , Wang Licheng , Xiao Junjun
Published: June 2023

The local surface plasmon resonance (LSPR) effect has been widely used in various nanophotonic applications. However, because the LSPR effect is highly sensitive to the structure and geometry, it is desirable to efficiently search viable geometries for predefined local field enhancement spectrum. Herein we present a generative adversarial network-based LSPR nanoantenna design scheme. By encoding the antenna structure information into an red-green-blue (RGB) color image, the corresponding nanoantenna structure can be inverse-designed to achieve the required enhancement spectrum of the local field. The proposed scheme can accurately offer the multiple geometry layout for the customized specific spectrum in seconds, which could be beneficial for fast design and fabrication of plasmonic nanoantenna.
Dynamic low-count PET image reconstruction using spatio-temporal primal dual network
Authors: Hu Rui , Cui Jianan , Li Chenxu , Yu Chengjin , Chen Yunmei , Liu Huafeng
Published: June 2023

Objective.Dynamic positron emission tomography (PET) imaging, which can provide information on dynamic changes in physiological metabolism, is now widely used in clinical diagnosis and cancer treatment. However, the reconstruction from dynamic data is extremely challenging due to the limited counts received in individual frame, especially in ultra short frames. Recently, the unrolled model-based deep learning methods have shown inspiring results for low-count PET image reconstruction with good interpretability. Nevertheless, the existing model-based deep learning methods mainly focus on the spatial correlations while ignore the temporal domain.Approach.In this paper, inspired by the learned primal dual (LPD) algorithm, we propose the spatio-temporal primal dual network (STPDnet) for dynamic low-count PET image reconstruction. Both spatial and temporal correlations are encoded by 3D convolution operators. The physical projection of PET is embedded in the iterative learning process of the network, which provides the physical constraints and enhances interpretability.Main results.The experiments of both simulation data and real rat scan data have shown that the proposed method can achieve substantial noise reduction in both temporal and spatial domains and outperform the maximum likelihood expectation maximization, spatio-temporal kernel method, LPD and FBPnet.Significance.Experimental results show STPDnet better reconstruction performance in the low count situation, which makes the proposed method particularly suitable in whole-body dynamic imaging and parametric PET imaging that require extreme short frames and usually suffer from high level of noise.
Multiple mixed state variable incremental integration for reconstructing extreme multistability in a novel memristive hyperchaotic jerk system with multiple cubic nonlinearity
Authors: Wang 王 Meng-Jiao 梦蛟 , Gu 辜 Lingfang 玲芳
Published: June 2023

Memristor-based chaotic systems with infinite equilibria are interesting because they generate extreme multistability. Their initial state-dependent dynamics can be explained in a reduced-dimension model by converting the incremental integration of the state variables into system parameters. However, this approach cannot solve memristive systems in the presence of nonlinear terms other than the memristor term. In addition, the converted state variables may suffer from a degree of divergence. To allow simpler mechanistic analysis and physical implementation of extreme multistability phenomena, this paper uses a multiple mixed state variable incremental integration (MMSVII) method, which successfully reconstructs a four-dimensional hyperchaotic jerk system with multiple cubic nonlinearities except for the memristor term in a three-dimensional model using a clever linear state variable mapping that eliminates the divergence of the state variables. Finally, the simulation circuit of the reduced-dimension system is constructed using Multisim simulation software and the simulation results are consistent with the MATLAB numerical simulation results. The results show that the method of MMSVII proposed in this paper is useful for analyzing extreme multistable systems with multiple higher-order nonlinear terms.
Linearity of minimally superintegrable systems in a static electromagnetic field
Authors: Bertrand S , Nucci M C
Published: June 2023

Fifteen three-dimensional classical minimally superintegrable systems in a static electromagnetic field are shown to possess hidden symmetries leading to their linearization, and consequently the corresponding subsets of maximally superintegrable subcases are also linearizable. These results are strengthening the conjecture that all three-dimensional minimally superintegrable systems are linearizable by means of hidden symmetries, even in the presence of a magnetic field.
Photovoltaic performance of lattice-matched gallium indium arsenide/germanium stannide dual-junction cell
Authors: Yu Tianjing , Cui Min , Li Qianying , Deng Jinxiang , Gao Hongli , Yuan Anjuan
Published: June 2023

Based on the photovoltaic properties and tandem solar cells theory, Gallium Indium Arsenide/Germanium Stannide (GaInAs/GeSn)-based double-junction (DJ) solar cells have been numerically simulated for the first time. In this study, we explore the band gap combination under lattice matching and obtain the content of In/Sn at optimal efficiency, which is expressed as Ga0.84In0.16As/Ge0.93Sn0.07 DJ solar cell (1.20/0.58 eV). Afterward, it is optimized in terms of variation in the doping contents and active layer thickness. To take full advantage of the electron mobility of the material, the optimal ‘inverted doping profile’ concentration N
a(d) is 1.5(5)/5(20) × 1018 cm−3. In addition, the reasonable p(n) layer thickness could be comprised of 0.2–0.8(0.2–1)/0.5–3(1–4) μm of the DJ solar cells with less material consumption. When the p(n) layer thickness is 0.30(0.25)/0.9(1.35) μm, the tandem device can achieve an optimal efficiency of 31.00% with 28.98 mA cm−2 (J
sc), 1.25 V (V
oc) and 85% (FF). This study highlights that GeSn materials have the potential to combine with III–V materials to form low-cost and high-efficiency tandem devices.
Preparation of a beam emission spectroscopy diagnostic based on a Lyman-alpha line to diagnose core and edge-plasma density fluctuation on the HL-2A tokamak
Authors: YU Yi , ZHOU Yixuan , KE Rui , NIE Lin , XIAO Chijie , LI Jiquan , HAO Guangzhou , XU Min , WANG Zhibin , CHEN Jian
Published: June 2023

In this article, the design of a Lyman-alpha-based beam emission spectroscopy (LAB) diagnostic on the HL-2A tokamak has been proposed for the first time. The purpose of this novel diagnostic is to measure density fluctuations of tokamak plasma. The light-collection system of LAB, which consists of the first mirror and two groups of coaxial double-mirror telescopes, can realize a two-segmented viewing field of ρ = 0‒0.2 and ρ = 0.75‒1, which is optimized to measure plasma density fluctuation, not only in the edge transport barrier region but also in the internal transport barrier region, to investigate the underlying physics of turbulence in tokamaks. Spectrometers are developed to separate out the Doppler-shifted target line (122.03 and 122.17 nm) from the background Lyman-alpha line (121.53 nm). Here, 30 Core-LAB channels and 30 Edge-LAB channels are under development on the HL-2A tokamak. It has high radial spatial resolutions of about 2.7 mm and 3.3 mm for the core and edge channels, respectively. Taking the high light intensity of this Lyman-alpha line into account, temporal resolution of 200 kHz can be ensured by broad bandwidth amplifiers. This high spatio-temporal resolution makes LAB a potential keen tool to experimentally investigate tokamak plasma physics.
Evaluation of in vitro immunostimulatory and cytotoxic effects of recombinant survivin protein in combination with doxorubicin and breast cancer antigen-loaded polycaprolactone nanoparticles
Authors: Dinparvar Sahar , Abamor Emrah Sefik , Oztav Sedanur , Inci Tugba Gul , Ihlamur Murat , Baghirova Malahat , Turgut-Balik Dilek , Allahverdiyev Adil M
Published: June 2023

In this study, the immunostimulatory and anticancer activities of the doxorubicin (DOX), MCF-7 and MDA-MB-231 breast cancer antigen-loaded polycaprolactone (PCL) nanoparticles (NPs) in combination with survivin recombinant protein (RP) and an alum adjuvant are evaluated in vitro on J774 macrophage, MCF-7 and MDA-MB-231 breast cancer cell lines. A double-emulsion solvent evaporation method was used for encapsulation of DOX and antigens into PCL NPs. The physicochemical characterization of NPs included size, morphology, zeta potential, release profiles and encapsulation efficiencies, analyzed using scanning electron microscopy, a zeta-sizer and UV–vis spectrometry. The cytotoxic and inhibitory effects of NPs were determined using a methyl thiazolyl tetrazolium assay. Immunostimulatory effects of the NPs were detected by Griess reaction and ELISA tests to determine nitric oxide and cytokine levels, respectively. According to the results, DOX and antigen-loaded PCL NPs ranged between 240 nm and 290 nm. Antigen and drug-loaded NPs appear less toxic over macrophage cells in comparison with non-capsulated free agents. In addition, considerable inhibitory effects of antigen and drug-loaded NPs were observed at non-toxic concentrations, such as 25 and 50 μg ml−1, on human mammary cancer cell lines (p⩽ 0.0001). The amount of nitrite released from macrophages that were treated with antigen and DOX-encapsulated PCL NPs, in combination with alum and survivin RP, after 96 h incubation was significantly higher than the control, especially at 50 and 100 μg ml−1, and triggered macrophages to produce high quantities of IL-4 and IL-12 cytokines in contrast to the control. As a result, DOX and antigen-loaded PCL NPs in combination with survivin and alum adjuvant revealed significant immunostimulatory and inhibiting influence on macrophage and breast cancer cells, respectively. The outcomes revealed that antigen and drug-loaded PCL NPs supplemented with survivin RP and an alum adjuvant created an effective platform for the development of nanotechnology-based immunotherapeutic tools to inhibit breast cancer cells. However, these outputs should be supported by further in vivo studies.
Facets of optically and magnetically induced heating in ferromagnetically doped-NaYF4 particles
Authors: Chakraborty Snigdhadev , Nalupurackal Gokul , Gunaseelan M , Roy Srestha , Lokesh Muruga , Goswami Jayesh , Datta Priyankan , Sinha Mahapatra Pallab , Roy Basudev
Published: June 2023

Upconverting particles like Yb and Er-doped NaYF4 are known to heat up after illumination with light at pump wavelength due to inefficient upconversion processes. Here we show that NaYF4 particles which have been co-doped not only with Yb and Er but also Fe improves the photothermal conversion efficiency. In addition, we show for the first time that alternating magnetic fields also heat up the ferromagnetic particles. Thereafter we show that a combination of optical and magnetic stimuli significantly increases the heat generated by the particles.
A generalized scattering theory in quantum mechanics
Authors: Wang Huai-Yu
Published: June 2023

In quantum mechanics textbooks, a single-particle scattering theory is introduced. In the present work, a generalized scattering theory is presented, which can be in principle applied to the scattering problems of arbitrary number of particle. In laboratory frame, a generalized Lippmann-Schwinger scattering equation is derived. We emphasized that the derivation is rigorous, even for treating infinitesimals. No manual operation such as analytical continuation is allowed. In the case that before scattering N particles are plane waves and after the scattering they are new plane waves, the transition amplitude and transition probability are given and the generalized S matrix is presented. It is proved that the transition probability from a set of plane waves to a new set of plane waves of the N particles equal to that of the reciprocal process. The generalized theory is applied to the cases of one- and two-particle scattering as two examples. When applied to single-particle scattering problems, our generalized formalism degrades to that usually seen in the literature. When our generalized theory is applied to two-particle scattering problems, the formula of the transition probability of two-particle collision is given. It is shown that the transition probability of the scattering of two free particles is identical to that of the reciprocal process. This transition probability and the identity are needed in deriving Boltzmann transport equation in statistical mechanics. The case of identical particles is also discussed.
Social media and volunteer rescue requests prediction with random forest and algorithm bias detection: a case of Hurricane Harvey
Authors: Mihunov Volodymyr V , Wang Kejin , Wang Zheye , Lam Nina S N , Sun Mingxuan
Published: June 2023

AI fairness is tasked with evaluating and mitigating bias in algorithms that may discriminate towards protected groups. This paper examines if bias exists in AI algorithms used in disaster management and in what manner. We consider the 2017 Hurricane Harvey when flood victims in Houston resorted to social media to request for rescue. We evaluate a Random Forest regression model trained to predict Twitter rescue request rates from social-environmental data using three fairness criteria (independence, separation, and sufficiency). The Social Vulnerability Index (SVI), its four sub-indices, and four variables representing digital divide were considered sensitive attributes. The Random Forest regression model extracted seven significant predictors of rescue request rates, and from high to low importance they were percent of renter occupied housing units, percent of roads in flood zone, percent of flood zone area, percent of wetland cover, percent of herbaceous, forested and shrub cover, mean elevation, and percent of households with no computer or device. Partial Dependence plots of rescue request rates against each of the seven predictors show the non-linear nature of their relationships. Results of the fairness evaluation of the Random Forest model using the three criteria show no obvious biases for the nine sensitive attributes, except that a minor imperfect sufficiency was found with the SVI Housing and Transportation sub-index. Future AI modeling in disaster research could apply the same methodology used in this paper to evaluate fairness and help reduce unfair resource allocation and other social and geographical disparities.
Seasonal effects on blue-green space preferences: examining spatial configuration and residents’ perspectives
Authors: Ma Fengdi
Published: June 2023

Urban blue-green spaces offer numerous environmental and social benefits to human beings. As these spaces vary by season, residents’ preferences may also change. However, the seasonal differences in preferences and the factors influencing waterfront degree preferences in different seasons remain unclear. This study employs space syntax theory to measure the configurational attributes of blue-green spaces in Changhe Park, Dezhou, China, and utilizes a four-section questionnaire to investigate residents’ preferences. The methods applied in this research include convex analysis, Mann-Whitney U test, and Spearman’s rho correlation analysis. The main findings are fourfold: (1) park users predominantly consist of older, less educated, and lower-income individuals; (2) blue spaces have higher choice values than green spaces; (3) season significantly impacts waterfront preferences, with 21.8% of respondents preferring high-degree waterfronts in summer, compared to 4.6% in winter; (4) age group is the sole decisive factor for blue space preference in summer, while sex and time spent in the park contribute to winter preferences. These findings contribute to the understanding of seasonal preferences for urban blue-green spaces and inform planning and design strategies, such as targeting specific demographic groups or adjusting waterfront features to enhance year-round appeal.
Analytical expressions for the design of twin junction tuning in SIS mixers
Authors: Wenninger J , Yassin G , Tan B-K
Published: June 2023

We derive general analytical expressions for matching the complex impedance of the feeding radio frequency (RF) circuit to a twin junction device in Superconductor-Insulator-Superconductor (SIS) mixers. A unique feature of our analysis is that it allows for junctions of different admittance and an RF circuit with complex admittance. This provides important design flexibility and accommodates device fabrication tolerances. We then focus on special cases of identical junctions, in particular those cases that yield simple expressions for matching the twin junction to a real impedance. Finally, we derive design curves that allow the determination of the twin junction parameters for a given complex impedance of the feeding circuit. These curves allow the designer to choose different solutions than the commonly used quarter-wavelength transmission line separating the two SIS junctions, which our analysis shows is not always the optimal solution. Moreover, even when commercial software is used for designing the circuits, our analytical equations will act as an important guide to understanding the physics and guide the designer to the optimal solution.
Simulation of a direct torque control system in the presence of winding asymmetry in induction motor
Authors: Goolak Sergey , Liubarskyi Borys , Riabov Ievgen , Chepurna Nataliia , Pohosov Oleksandr
Published: June 2023

The operation of a direct torque control (DTC) system for induction motors with the possible presence of unbalanced modes in the motor windings is studied. It is shown that in the presence of asymmetric modes in the motor windings, the classical DTC algorithm becomes unstable. It is proposed to improve the DTC by taking into account the unbalance of the active resistances of the motor stator windings when determining the DTC parameters. This will make it possible to study electrodynamic processes in DTC with the possible presence of asymmetric modes in the windings of induction motor.
Impact analysis of ceramic tile powder aggregates on self-compacting concrete
Authors: Harikaran M , Boopathi Sampath , Rajkannan M , Gokulakannan S
Published: June 2023

Waste ceramic tile (CT) powders are used to improve the workability, mechanical properties, and durability of self-compacting concrete (SCC). The waste CT powder is prepared by mixing construction tiles, sanitary fittings, and electrical insulators, with different weight percentages mixed into the SCC. Experiments have been conducted to evaluate the workability, mechanical, and durability of SCC. The optimum compressive, flexural, and tensile strengths were predicted to be 52.5 MPa, 8.5 MPa, and 7.8 MPa. SCC’s durability and workability characteristics are achieved by mixing 50% CT powder, which increases interlocking properties and meets EFNARC standards. It is concluded that CT powder can be substituted for conventional fine aggregate in concrete, increasing compressive, flexural, and split tensile strengths by 12.5%, 9.33%, and 28.76% compared to conventional SCC. The 50% CT powder mixed SCC is the optimum value for achieving optimal mechanical, durability, and workability characteristics. Samples of 50% CT powder-mixed SCC with 7, 28, and 90 days of curing processes and microstructure are also illustrated.
A controlled transfer entropy approach to detect asymmetric interactions in heterogeneous systems
Authors: Das Rishita , Porfiri Maurizio
Published: June 2023

Transfer entropy is emerging as the statistical approach of choice to support the inference of causal interactions in complex systems from time-series of their individual units. With reference to a simple dyadic system composed of two coupled units, the successful application of net transfer entropy-based inference relies on unidirectional coupling between the units and their homogeneous dynamics. What happens when the units are bidirectionally coupled and have different dynamics? Through analytical and numerical insights, we show that net transfer entropy may lead to erroneous inference of the dominant direction of influence that stems from its dependence on the units’ individual dynamics. To control for these confounding effects, one should incorporate further knowledge about the units’ time-histories through the recent framework offered by momentary information transfer. In this realm, we demonstrate the use of two measures: controlled and fully controlled transfer entropies, which consistently yield the correct direction of dominant coupling irrespective of the sources and targets individual dynamics. Through the study of two real-world examples, we identify critical limitations with respect to the use of net transfer entropy in the inference of causal mechanisms that warrant prudence by the community.
Agarose Gel: An Overview of the Dermal Filler and a Clinical Experience With 700 Patients
Authors: Buhsem Omer , Kirazoglu Ahmet
Published: June 2023

Background

Dermal fillers currently in the market have several advantages and disadvantages over each other. Agarose gel (AG) is a unique material due to its special rheological characteristics and gel-forming capability.

Objectives

The authors aimed to share their clinical experience on AG for a variety of facial augmentation procedures and its long-term results.

Methods

The study population consisted of 700 patients (532 females; 168 males) aged 18 to 52 years. Follow-up visits were at 1, 3, 6, 12, and 24 months after the injections. Patient satisfaction was evaluated on a scale from 0 to 10 using a survey and clinical improvement was evaluated using the Global Aesthetic Improvement Scale (GAIS) by 2 independent plastic surgeons before the injection and at 1-year follow-up.

Results

Eighty-two percent of the patients scored 1 or 2 (exceptional or great improvement) on GAIS. Eighty-five percent of the patients scored 8 or above (very satisfied). Most patients experienced at least 80% persistence of effect at 1-year follow-up.

Conclusions

AG appears to be suitable for a variety of facial augmentation and contouring applications, as it is safe and has long-lasting favorable cosmetic efficacy.

Level of Evidence: 3
Condition dependence of (un)predictability in escape behavior of a grasshopper species
Authors: Winter Gabe , Wirsching Luis , Schielzeth Holger
Published: June 2023

(Un)predictability has only recently been recognized as an important dimension of animal behavior. Currently, we neither know if (un)predictability encompasses one or multiple traits nor how (un)predictability is dependent on individual conditions. Knowledge about condition dependence, in particular, could inform us about whether predictability or unpredictability is costly in a specific context. Here, we study the condition dependence of (un)predictability in the escape behavior of the steppe grasshopper Chorthippus dorsatus. Predator–prey interactions represent a behavioral context in which we expect unpredictability to be particularly beneficial. By exposing grasshoppers to an immune challenge, we explore if individuals in poor condition become more or less predictable. We quantified three aspects of escape behavior (flight initiation distance, jump distance, and jump angle) in a standardized setup and analyzed the data using a multivariate double-hierarchical generalized linear model. The immune challenge did not affect (un)predictability in flight initiation distance and jump angle, but decreased unpredictability in jump distances, suggesting that unpredictability can be costly. Variance decomposition shows that 3–7% of the total phenotypic variance was explained by individual differences in (un)predictability. Covariation between traits was found both among averages and among unpredictabilities for one of the three trait pairs. The latter might suggest an (un)predictability syndrome, but the lack of (un)predictability correlation in the third trait suggests modularity. Our results indicated condition dependence of (un)predictability in grasshopper escape behavior in one of the traits, and illustrate the value of mean and residual variance decomposition for analyzing animal behavior.
A statistical algorithm for outbreak detection in multisite settings: an application to sick leave monitoring
Authors: Duchemin Tom , Noufaily Angela , Hocine Mounia N
Published: June 2023

Motivation

Public health authorities monitor cases of health-related problems over time using surveillance algorithms that detect unusually high increases in the number of cases, namely aberrations. Statistical aberrations signal outbreaks when further investigation reveals epidemiological significance. The increasing availability and diversity of epidemiological data and the most recent epidemic threats call for more accurate surveillance algorithms that not just detect aberration times but also detect locations. Sick leave data, for instance, can be monitored across companies to identify companies-related aberrations. In this context, we develop an extension to multisite surveillance of a routinely used aberration detection algorithm, the quasi-Poisson regression Farrington Flexible algorithm. The new algorithm consists of a negative-binomial mixed effects regression model with a random effects term for sites and a new reweighting procedure reducing the effect of past aberrations.

Results

A wide range of simulations shows that, compared with Farrington Flexible, the new algorithm produces better false positive rates and similar probabilities of detecting genuine outbreaks, for case counts that exceed historical baselines by 3 SD. As expected, higher surges lead to lower false positive rates and higher probabilities of detecting true outbreaks. The new algorithm provides better detection of true outbreaks, reaching 100%, when cases exceed eight baseline standard deviations. We apply our algorithm to sick leave rates in the context of COVID-19 and find that it detects the pandemic effect. The new algorithm is easily implementable over a range of contrasting data scenarios, providing good overall performance and new perspectives for multisite surveillance.

Availability and implementation

All the analyses are performed in the R statistical software using the package glmmTMB. The code for performing the analyses and for generating the simulations can be found online at the following link: https://github.com/TomDuchemin/mixed_surveillance.

Contact

a.noufaily@warwick.ac.uk
Oncoplastic breast surgery in older women with primary breast cancer: systematic review
Authors: Chia Zoe , Lee Rachel X N , Cardoso Maria J , Cheung Kwok Leung , Parks Ruth M
Published: June 2023

Background

Oncoplastic procedures allow excision of larger breast tumours, or unfavourable tumour/breast ratio lesions while achieving a good cosmetic outcome. This increases the pool of patients eligible for breast conservation over mastectomy, reducing the need for more extensive surgery in older women and potentially improving their quality of life. Nonetheless, studies to date suggest a poor uptake of oncoplastic breast surgery in the older group. This review aimed to establish whether a disparity in uptake of oncoplastic breast surgery exists between older and younger women, and to explore the underlying reasons for this.

Methods

A literature search was conducted on 17 January 2022 using MEDLINE and Embase. Eligible studies comprised full-text articles of patients who underwent oncoplastic breast surgery for primary invasive breast cancer, and included those aged at least 65 years.

Results

Ten published studies were identified. One study was ranked as providing level 2 evidence, and the remainder were level 3. A total of 567 women underwent oncoplastic breast surgery for primary breast cancer, of whom only 61 (10.8 per cent) were aged 65 years or older. None of the studies directly compared younger with older women, or explored the underlying factors contributing to this discrepancy in uptake.

Conclusion

This review has demonstrated a lower uptake of oncoplastic breast surgery in older compared with younger women. Given the increasing number of older women living with breast cancer who may be eligible for breast-conserving surgery, further research into this area is required.
Psychodermatology knowledge, awareness and patterns of practice among Moroccan dermatologists: a national survey study
Authors: Ait Oussous Sara , Jafferany Mohammad , Chakiri Radia
Published: June 2023

We aimed to assess the knowledge, attitudes and patterns of practice of Moroccan dermatologists and their awareness of psychodermatology (PD). A survey questionnaire was distributed to dermatologists and dermatology trainees from May to July 2022. A total of 112 completed surveys were received. Of these, 63.4% were dermatologists and 36.6% were dermatology residents. Of the participants, 72.3% summarized PD as the psychological impact of dermatological conditions and 50.9% reported frequent involvement with PD. Patients with a psychocutaneous condition represented a significant proportion of dermatological consultations (41.1% of dermatologists stated that 10–25% of their consultations were for psychocutaneous conditions). Only 17% felt ‘very comfortable’ in the management of PD conditions and 56.3% were not confident prescribing psychotropics. A total of 88.4% had never participated in PD training. Moroccan dermatologists lack a full understanding and proper training in PD. We recommend the incorporation of PD curriculum in training programmes and advocate dermatology and psychiatry liaison.
Opportunity for significant reduction in risk of major adverse cardiac events with screening for cardiovascular disease risk factors in hidradenitis suppurativa
Authors: Kearney Niamh , Hughes Rosalind , McCourt Collette , O’Kane Donal , Kirby Brian
Published: June 2023

Patients with hidradenitis suppurativa (HS) have a high prevalence of cardiovascular disease risk factors and are at increased risk of major adverse cardiac events (MACE). Routine screening for risk factors is recommended but the benefit of this in risk reduction has not been evaluated. In this study of 117 patients attending hospital-based services for HS, there was a high burden of undiagnosed cardiovascular disease risk factors. Risk factor optimization significantly reduced 10-year risk of MACE.
Cortical alterations after very preterm birth and the association with socio-emotional abilities from childhood to early adolescence
Authors: Siffredi Vanessa , Liverani Maria Chiara , Borradori-Tolsa Cristina , Leuchter Russia Hà-Vinh , Thiran Jean-Philippe , Hüppi Petra S , Fischi-Gómez Elda
Published: June 2023

Very preterm birth (VPT; <32 weeks’ gestation) leads to a situation where crucial steps of brain development occur in an abnormal ex utero environment, translating to vulnerable cortical and subcortical development. Associated with this atypical brain development, children and adolescents born VPT are at a high risk of socio-emotional difficulties. In the current study, we unravel developmental changes in cortical gray matter (GM) concentration in VPT and term-born controls aged 6–14 years, together with their associations with socio-emotional abilities. T1-weighted images were used to estimate signal intensities of brain tissue types in a single voxel (GM, white matter, and cortico-spinal fluid) and extract GM concentration disentangled from the presence of partial volume effects (PVEs). General linear model analysis was used to compare groups. Socio-emotional abilities were assessed and associations with GM concentration were explored using univariate and multivariate analyses. The effects of prematurity were far-reaching, with intricated patterns of increases and decreases of GM concentration mainly in frontal, temporal, parietal, and cingular regions. Better socio-emotional abilities were associated with increased GM concentration in regions known to be involved in such process for both groups. Our findings suggest that the trajectory of brain development following VPT birth may be fundamentally distinctive and impact socio-emotional abilities.
Risk of Tuberculosis Disease in People With Chronic Kidney Disease Without Kidney Failure: A Systematic Review and Meta-analysis
Authors: Luczynski Pauline , Holmes Thomas , Romanowski Kamila , Arbiv Omri A , Cook Victoria J , Clark Edward G , Johnston James C
Published: June 2023

Background

Kidney failure is an established risk factor for tuberculosis (TB), but little is known about TB risk in people with chronic kidney disease (CKD) who have not initiated kidney replacement therapy (CKD without kidney failure). Our primary objective was to estimate the pooled relative risk of TB disease in people with CKD stages 3–5 without kidney failure compared with people without CKD. Our secondary objectives were to estimate the pooled relative risk of TB disease for all stages of CKD without kidney failure (stages 1–5) and by each CKD stage.

Methods

This review was prospectively registered (PROSPERO CRD42022342499). We systematically searched MEDLINE, Embase, and Cochrane databases for studies published between 1970 and 2022. We included original observational research estimating TB risk among people with CKD without kidney failure. Random-effects meta-analysis was performed to obtain the pooled relative risk.

Results

Of the 6915 unique articles identified, data from 5 studies were included. The estimated pooled risk of TB was 57% higher in people with CKD stages 3–5 than in people without CKD (adjusted hazard ratio: 1.57; 95% CI: 1.22−2.03; I2 = 88%). When stratified by CKD stage, the pooled rate of TB was highest in stages 4–5 (incidence rate ratio: 3.63; 95% CI: 2.25–5.86; I2 = 89%).

Conclusions

People with CKD without kidney failure have an increased relative risk of TB. Further research and modeling are required to understand the risks, benefits, and CKD cutoffs for screening people for TB with CKD prior to kidney replacement therapy.
APOE4, Age, and Sex Regulate Respiratory Plasticity Elicited by Acute Intermittent Hypercapnic-Hypoxia
Authors: Nair Jayakrishnan , Welch Joseph F , Marciante Alexandria B , Hou Tingting , Lu Qing , Fox Emily J , Mitchell Gordon S
Published: June 2023

Rationale

Acute intermittent hypoxia (AIH) shows promise for enhancing motor recovery in chronic spinal cord injuries and neurodegenerative diseases. However, human trials of AIH have reported significant variability in individual responses.

Objectives

Identify individual factors (eg, genetics, age, and sex) that determine response magnitude of healthy adults to an optimized AIH protocol, acute intermittent hypercapnic-hypoxia (AIHH).

Methods

In 17 healthy individuals (age = 27 ± 5 yr), associations between individual factors and changes in the magnitude of AIHH (15, 1-min O2 = 9.5%, CO2 = 5% episodes) induced changes in diaphragm motor-evoked potential (MEP) amplitude and inspiratory mouth occlusion pressures (P0.1) were evaluated. Single nucleotide polymorphisms (SNPs) in genes linked with mechanisms of AIH induced phrenic motor plasticity (BDNF, HTR2A, TPH2, MAOA, NTRK2) and neuronal plasticity (apolipoprotein E, APOE) were tested. Variations in AIHH induced plasticity with age and sex were also analyzed. Additional experiments in humanized (h)ApoE knock-in rats were performed to test causality.

Results

AIHH-induced changes in diaphragm MEP amplitudes were lower in individuals heterozygous for APOE4 (i.e., APOE3/4) compared to individuals with other APOE genotypes (P = 0.048) and the other tested SNPs. Males exhibited a greater diaphragm MEP enhancement versus females, regardless of age (P = 0.004). Additionally, age was inversely related with change in P0.1 (P = 0.007). In hApoE4 knock-in rats, AIHH-induced phrenic motor plasticity was significantly lower than hApoE3 controls (P < 0.05).

Conclusions

APOE4 genotype, sex, and age are important biological determinants of AIHH-induced respiratory motor plasticity in healthy adults.

Addition to Knowledge Base

AIH is a novel rehabilitation strategy to induce functional recovery of respiratory and non-respiratory motor systems in people with chronic spinal cord injury and/or neurodegenerative disease. Figure 5 Since most AIH trials report considerable inter-individual variability in AIH outcomes, we investigated factors that potentially undermine the response to an optimized AIH protocol, AIHH, in healthy humans. We demonstrate that genetics (particularly the lipid transporter, APOE), age and sex are important biological determinants of AIHH-induced respiratory motor plasticity
Direct implementation of discontinuous-grid finite-difference method using multiple point sources method and dynamic wavefield injection
Authors: Miao Zhongzheng , Zhang Jinhai
Published: June 2023

The classical finite-difference (FD) method stimulates wave propagation in uniform grids. In models with considerable velocity variations, the computational efficiency is compromised by oversampling in time and space. Although adopting a discontinuous grid in different wave-speed regions can improve computational efficiency, such a technique is typically hindered by low accuracy in transition zones (i.e. in the vicinity of the discontinuous-grid interface) and is typically unstable in the long term. We propose a direct implementation of the discontinuous-grid FD method by performing two simulations simultaneously: one on a coarse grid and the other on a fine grid. The proposed method applies a dynamic injection strategy to manage wavefield communication between coarse and fine submodels. Compared with previous discontinuous-grid FD methods, where the number of layers required for wavefield communication is one-half that the order of the FD scheme, the proposed method only requires one single layer, which significantly reduces the communication overhead and suppresses wavefield errors. Numerical experiments show that the results yielded by our method are consistent with the reference solutions yielded by the uniform-grid FD method via a fine grid. Furthermore, our method does not encounter numerical instability in long-term simulations. Therefore, the proposed discontinuous-grid FD method can accelerate numerical simulations while retaining stable numerical accuracy, even for long-term simulations.
Determining sampling spacing according to volume of investigation in geophysical surveys, application of air dose rate mapping
Authors: Masoudi Pedram
Published: June 2023

Geophysical measurements are a sort of averaging a physical property over a volume of investigation (VOI). Within the VOI, the spatial elements closer to the detector contribute more to the measured value compared to farther elements. In this study, a VOI-oriented algorithm is proposed which establishes a relation between the localization probability, the sampling spacing and the size of the exploration target. Hence, the probability of localizing a target could be calculated as a function of sampling spacing when the target dimension is known. The novelty of this work is the use of VOI in the sampling optimization, which is important for geophysical survey design in environmental sampling and mineral exploration. Although the published sampling optimization methods are often variogram-oriented, the one presented here is based on the spatial variability of the measured property. Finally, coupling the VOI-oriented algorithm with a variogram model could be recommended in order to consider both the measurement mechanism and the spatial variability in the sampling design.
quarTeT: a telomere-to-telomere toolkit for gap-free genome assembly and centromeric repeat identification
Authors: Lin Yunzhi , Ye Chen , Li Xingzhu , Chen Qinyao , Wu Ying , Zhang Feng , Pan Rui , Zhang Sijia , Chen Shuxia , Wang Xu , Cao Shuo , Wang Yingzhen , Yue Yi , Liu Yongsheng , Yue Junyang
Published: June 2023

A high-quality genome is the basis for studies on functional, evolutionary, and comparative genomics. The majority of attention has been paid to the solution of complex chromosome structures and highly repetitive sequences, along with the emergence of a new ‘telomere-to-telomere (T2T) assembly’ era. However, the bioinformatic tools for the automatic construction and/or characterization of T2T genome are limited. Here, we developed a user-friendly web toolkit, quarTeT, which currently includes four modules: AssemblyMapper, GapFiller, TeloExplorer, and CentroMiner. First, AssemblyMapper is designed to assemble phased contigs into the chromosome-level genome by referring to a closely related genome. Then, GapFiller would endeavor to fill all unclosed gaps in a given genome with the aid of additional ultra-long sequences. Finally, TeloExplorer and CentroMiner are applied to identify candidate telomere and centromere as well as their localizations on each chromosome. These four modules can be used alone or in combination with each other for T2T genome assembly and characterization. As a case study, by adopting the entire modular functions of quarTeT, we have achieved the Actinidia chinensis genome assembly that is of a quality comparable to the reported genome Hongyang v4.0, which was assembled with the addition of manual handling. Further evaluation of CentroMiner by searching centromeres in Arabidopsis thaliana and Oryza sativa genomes showed that quarTeT is capable of identifying all the centromeric regions that have been previously detected by experimental methods. Collectively, quarTeT is an efficient toolkit for studies of large-scale T2T genomes and can be accessed at http://www.atcgn.com:8080/quarTeT/home.html without registration.