bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation and Reinforcement of Prestressed Concrete Hollow Slab Bridge after Fire Damage
Authors: Huang XX , Zeng Y
Published: April 2023

The bearing capacity of bridges after fire cannot be clearly defined, and the bearing capacity of bridges after fire cannot be evaluated by actual bridge load tests. In order to solve this problem, this paper studies the actual bearing capacity and reinforcement methods of hollow slab bridges after fire, combined with practical engineering cases. During the operation period of 16m span prestressed concrete hollow slab after fire detection, the bearing capacity is calculated according to the appearance, rebound strength, carbonization depth of the fire zone of the hollow slab and pier, as well as the compressive strength of coring, the tensile strength of steel, the natural frequency of vibration, dynamic strain and deflection of the hollow slab; The research results show that the bearing capacity of bridges after fire calculated by this method is more accurate, and the reinforcement scheme is formulated according to the calculated bearing capacity, which has achieved good results after reinforcement. It providing a reference for the detection and reinforcement of similar bridge diseases.
LCS-based Visual Recognition for AGV Guide Paths under Complex Illumination Conditions
Authors: Wang ZM , Li M , Gao C , Jin XM
Published: April 2023

Complex lighting is one of the most challenging problems in automatic guided vehicle (AGV) vision recognition system. In order to overcome the influence of uneven illumination on the accuracy and robustness of path recognition, this paper proposes the LCS based visual recognition for AGV guide paths under complex illumination conditions method, which converts the collected image into an invariant image through logarithmic chromaticity space (LCS) to eliminate the influence of illumination, and the minimum average entropy angle is used as the projection angle to generate the invariant image to improve the speed of image conversion to the invariant image. Experimental results show that the proposed method can effectively improve the robustness of AGV vision recognition system under complex lighting conditions.
Terminal Access Method of Power Equipment Based on eSIM in WSN Environment
Authors: Fu YF , Zhang XM , Yang ZP
Published: April 2023

To ensure the integration of wireless sensor network and broadband wireless communication network, we establish a new generation of power IoTs information communication system for smart grid, and propose a distribution automation terminal solution based on eSIM card. An adaptive access algorithm based on multi logic eSIM priority, and a WSN based power acquisition system architecture, are also put forward. Then, according to the statistical analysis results of service arrival, the dialing and location information are integrated into one module. Through terminal classification and mobile modeling, a remote management mechanism based on EUICC is finally established. The system simulation test results show that the strategy adopted in this article can reduce the terminal access blocking rate in heterogeneous network environment, and the support of eSIM in WSN environment increases the integration of power equipment.
Design of Data Quality Control System Based on ETL
Authors: Wang XP , Li JY
Published: April 2023

Aiming at the problems of incremental data extraction and task scheduling in ETL processing, an optimization strategy based on data quality control is proposed. We discuss the common mechanisms of data incremental extraction and quality control in the ET subsystem of data warehouse, and propose an incremental data extraction method based on key attribute comparison. The key functions of ETL data extraction is utilized, and the database incremental extraction method is adopted. During the process of data processing, the problem of data loss is solved by means of auxiliary tables, and the problem of data quality at the instance level is solved by data cleaning. Finally, the experimental results on real data sets show that the ETL design with quality control optimizes the overall workflow and ensures that data can be accurately extracted into the data warehouse.
Resource Allocation Optimization Algorithm of Power 5G Network Slice Based on NFV and SDN
Authors: Wang Qian , Zhang Yanan , Wang Xuanzhong
Published: April 2023

To realize 5G network slicing, the virtual resource scheduling and allocation method based on NFV and SDN is designed. The scheme comprehensively considers 5G communication technology and network slice structure, and establishes the optimal mathematical model of network slice operation economy. Then the network functions and resources are virtualized by NFV and SDN, the greedy algorithm is adopted to solve the mapping problem of network slices, and the specific implementation algorithm is provided. The simulation results show that the allocation algorithm can customize the management of network slice resources, achieve flexible control and sharing of network traffic and resources, and significantly promote the construction, optimization and promotion of 5G mobile communication network architecture.
Fast Access Method of IoT Smart Terminal Based On C/S Architecture
Authors: Sun F , Zhu S , Lin H , Xu N , Li H
Published: April 2023

In order to achieve efficient access and fast access of intelligent terminals, this paper proposes a fast access method for intelligent terminals of the Internet of Things based on C/S architecture. First, a terminal auto configuration program is developed; The automatic configuration program sends application configuration information to the configuration server; Then, the server verifies the identity of the terminal and feeds back the corresponding configuration information. Finally, the automatic configuration program automatically configures the terminal according to the feedback information and accesses the Internet of Things management platform. The experimental results show that this method can realize remote distribution of terminal configuration information and automatic configuration of terminals. Compared with traditional methods, the terminal access time can be reduced by about 70%.
Research on Energy Extraction Devices Based on High-Voltage Line Monitoring Technology
Authors: Lin Zhuang , Zhang Guangxin , Li Cheng , Cui Yuxin , Li Shilin , Zhou Fulin
Published: April 2023

With the construction and development of an intelligent power grid, the voltage level of transmission lines is constantly improved. The distribution of power grids is increasingly broad, the climate environment along the transmission lines is complicated, the safe and reliable operation of transmission lines is facing significant challenges, and the inspection and maintenance workload of transmission lines is also increasing. Currently, only 20% of the online monitoring devices of transmission lines installed by the State Grid can operate normally. Power failures cause the most. It can be seen that it is necessary to develop an efficient and reliable power supply to improve the reliability of online monitoring devices of transmission lines. In order to enable the transmission lines to operate independently without maintenance for a long time, now the power grid needs an energy harvesting device with good stability, high energy harvesting efficiency, and strong resistance.
Different non-isolated photovoltaic (PV) inverter topologies can suppress leakage currents
Authors: Zhang Yuxin
Published: April 2023

In recent years, due to various environmental protection policies and the popularity of new energy sources, photovoltaic power generation has been strongly encouraged and developed at home and abroad. Suppressing leakage current is a key issue for non-isolated PV grid-connected systems. This paper analyzes various circuit topologies proposed to suppress the leakage current based on the bridge structure. This paper will compare and analyze the representative circuit topologies among them, comparing their circuit diagrams, operating principles, pros and cons, and so on. The leakage current can be effectively suppressed by bipolar modulation, but it will produce great electromagnetic noise and full harmonic distortion, reducing system efficiency. The HERIC circuit has the highest conversion efficiency and the best leakage current suppression effect among the three half-bridge structures and three full-bridge structures summarized in this paper. By summarizing and comparing, future research efficiency will improve when similar problems arise.
Research on the Optimal Design of a New Hybrid DC Energy Dissipation Valve
Authors: Hu Yongjie , Xia Kepeng , Zhang Lei , Li Chengyu , Li Shuya
Published: April 2023

DC energy dissipation valve is the core equipment of offshore wind power flexible and direct transmission system. It is of great significance for protecting the operation safety of converter valve equipment and restraining the over-voltage of the DC bus in case of an AC fault at the receiving end. However, DC energy consumption device has many topologies and novel structure, and their equipment construction cost and operation reliability are one of the important factors limiting their engineering application. In this paper, the topological structure of a hybrid DC energy consumption device is studied, and the distributed resistance parameters of a hybrid DC energy consumption device are optimized. Based on the optimization scheme, a new switching control strategy and voltage sharing strategy are proposed, which improves the technical and economic efficiency of hybrid DC energy consumption devices. The feasibility of the proposed measures is verified through simulation and experiment, which is of engineering significance.
The leakage current suppression of transformerless three-level photovoltaic grid-connected inverter
Authors: Dong Shi , Liang Jiajun , Yang Jiaxin
Published: April 2023

Transformerless PV grid-connected inverters, although simple in construction and highly efficient, suffer from serious current leakage problems. There is no electrical isolation between the PV panels and the grid, and the parasitic capacitance causes the inverter to form a common mode loop with the earth, creating strong resonances in the high-frequency range and generating huge leakage currents. Today, the two main methods of leakage current suppression are topology and modulation. This paper observes leakage current suppression by comparing two modulation methods, SVPWM and 3D-SVPWM. In the case of the LCCL filter, the conventional SVPWM modulation causes the common mode voltage to oscillate at high frequencies of the order of magnitude of the carrier frequency, causing large leakage currents in the common mode loop. With 3D-SVPWM modulation, however, the common mode voltage pulses are equal in the positive and negative areas, attenuating the CM resonance and balancing the NP voltage, thus producing a smooth common mode voltage and effectively suppressing high-frequency leakage currents.
Research on Heterogeneous Data Fusion Technology of Substation Secondary Equipment
Authors: Ji Haichao , Zhang Xin , Yu Hai , Jia Deshun , Chang Zhiyu , Lin Kui
Published: April 2023

In intelligent substations, the MMS Lite software package is widely used to realize station control layer network communication based on IEC61850. The protocol uses the BER coding of ASN.1, so there is more redundant information, which affects the transmission efficiency. Under the background of domestic independent control in the domestic power industry, there have been increasingly urgent demands for transforming and upgrading intelligent substations based on MMS protocol. This paper proposes a heterogeneous data fusion method for the secondary equipment of substation monitoring systems, which supports the simultaneous access and data interaction of the bay-level equipment of CMS protocol and MMS protocol. The thread synchronization mechanism is studied to avoid the avalanche data loss caused by transient failure, and improve the safety and reliability of data operation and maintenance, which further improves the support for the operation monitoring, remote access, and other services of the centralized control master station.
Plate Condition Monitoring System Based on LoRa Wireless Transmission
Authors: Xu Kang , Chen Dan , Lin Feng , Tan Qin , Wen Hao
Published: April 2023

In the process of tension stringing of transmission lines, the condition of the plate needs manual reporting, so its safety is poor, and its efficiency is low. To solve this problem, this study constructs a plate condition monitoring system of tension stringing based on the LoRa wireless transmission. This system consists of a data acquisition system, a wireless communication transmission system, and a monitoring and warning center. The STM32 is used to process the data collected by the sensors, and the LoRa wireless communication system is designed by way of adaptive dynamic change of LoRa’s network ID, and the networking mode of the multi-node relay, and the data is sent to the upper computer from a distance, and the upper computer software is implemented by MFC, which can monitor the condition of the plate in real-time. The test results show that the packet loss rate of LoRa is less than 5%, and the condition data of the plate can be transmitted to the monitoring software through LoRa and displayed. This system has the advantages of strong confidentiality, far transmission, and high safety, which can be used for real-time monitoring of the condition of the plate in the process of tension stringing.
Multi-objective Optimization Model of the Bundled Wind-PV-thermal Power Transmission System
Authors: Li Hongqian , Xue Fei , Li Xutao , Li Hao , Tian Bei , Yang Ting
Published: April 2023

Aiming at the optimization problem of the bundled wind-PV-thermal power transmission system considering the renewable energy off-grid fault, this paper first establishes a optimization model to maximize the renewable energy(RE) consumption and minimize the system operation cost, and considers the impact of the renewable energy off-grid fault. Then, a reinforcement learning method for solving optimization model is proposed to solve the optimal output of generations at each time. It can reduce the operating cost and improve the consumption of renewable energy under the influence of off-grid failure. Finally, taking the actual wind farm, PV power station, energy storage station(ESS), and power plant in the northwest as an example, the advantages of the proposed strategy is proven.
A Measurement Amplification Method for TSV Weak Resistance
Authors: Gong Tao , Zeng Sheng , Chen Si , Lu Xiangjun , Shao Dengyun
Published: April 2023

In the TSV electromigration test process, this paper has carried out relevant research on how to accurately measure TSV resistance and make it conducive to the observation of standard instruments, aiming at the problem that the resistance value of TSV reaches the magnitude of a microburst. Observing the resistance value change in the electromigration process is challenging. This paper analyzes and designs a measurement circuit for TSV. This circuit uses the cascade of an integrated amplifier. It combines with the four-probe method to amplify the TSV resistance change signal based on accurate measurement of TSV resistance, which is more conducive to the measurement of standard instruments and makes it easier to observe the change of resistance when TSV electromigration occurs.
Research on lighting fault identification technology of transmission lines based on non-contact sensing
Authors: Jiang Kaihua , Zhu Jinhua , Shao Xianjun , Wang Shaohua , Li Te , Wang Zhenguo
Published: April 2023

According to field operation records, lightning stroke accounts for 60% of transmission line failures. Therefore, it is of great significance to strengthen lightning protection of the power system. However, there are several lightning faults, and the corresponding protection methods differ. Consequently, identifying lightning stroke faults will be beneficial to take corresponding lightning protection measures. This paper investigates the mechanism of different lightning strike faults, and simulates them by a 110kV transmission line EMTP-ATP model. Analysis and simulation show that the direction of tower current represents lightning’s polarity; the insulator voltage’s direction differs when shielding failure or back striking occurs. If insulator flashovers, the voltage of the insulator drops down to zero, and as the transient process comes to an end, the voltage of the insulator on the nearby tower decreases to zero as well; after the occurrence of back striking flashover, the direction of insulator voltage on nearby tower alters. Based on those features, insulator voltage and tower current are introduced as a characteristic signal, and their direction and rms of them are formed as recognition parameters for lightning stroke identification. The EMTP-ATP simulations demonstrate that the proposed method is correct and effective, and the recognition rate of different lightning faults is 100% under the abovementioned method.
Research on remote emergency control breaking device for trolley type circuit breaker switchgear
Authors: Liu Guojian , Sun Ruofeng , Xu Xiaoqing , Deng Qing , Yang Linqing
Published: April 2023

High-voltage transmission and distribution lines use circuit breaker switchgear for stopping and feeding operations. Therefore, if abnormal emergencies in circuit breaker shutdown and transmission, it is urgent to carry out remote control switching to solve the problem that the circuit breaker cannot be operated with power when the remote control fails. This paper develops a trolley type circuit breaker switchgear remote emergency control shunting device, which can remotely shunt the circuit breakers on the switchgear and sink control cabinet manually in situ. And we also discusses the hardware and software design principle as well as the advantage analysis to ensure the personal safety of the operators on site and provide reference for improving the safety, economy, flexibility and reliability of the power grid.
Research on MMC Circulation Suppression Technology
Authors: Yang Xuanyuan , Sheng Yifa
Published: April 2023

Modular multilevel converters (MMCs) are extensively used in flexible high-voltage DC transmission systems. As an important part of them, it plays an important role in the normal use of MMCs. The main additional loss in the system is generated by the second harmonic in the circulating current. By summarizing and comparing current circulation control strategies. Based on the current research status of circulation suppression, we prospect the research direction of the MMC circulating current suppression.
Research on Sensorless Control of Built-in Permanent Magnet Synchronous Motor Based on Extended Kalman Filter Algorithm
Authors: Lu Jianning , Wang Wenbin , Zhang Junshuai , Su Jiaqi
Published: April 2023

The permanent magnet synchronous motor (PMSM) is a system of complex interior structure coupling and nonlinear, variable parameters. In order to track and observe the position and speed of PMSM in real time, the extended Kalman filter (EKF) algorithm is used in this paper to track the speed and position of the built-in PMSM. The influence of the Q and R covariance matrix on the observation effect is studied by using the control variable method of trial and error. The reliability of the EKF on the observation function of velocity position is verified by MATLAB simulation.
Research on automatic correlation technology of virtual circuit in secondary system of intelligent substation
Authors: Zhao Zhicheng , Lu Donghai , Liu Shujun , Chen Shi , Ding Jiwei
Published: April 2023

In this paper, an automatic connection method of virtual terminals based on the distance weight vector optimization model is proposed to realize the automatic connection of virtual terminals. The method defines the similarity of virtual terminal connections based on the edit distance, establishes an optimization model based on the sample data of virtual connections, and uses the particle swarm optimization to calculate the distance weight vector, so that the edit distance similarity can be adapted to the equipment produced by various manufacturers. Finally, the dummy terminals in the two pending IEDs (Intelligent Electronic Devices) are matched based on the similarity, and the matching reliability is given. The calculation example results show that this method can accurately realize the automatic connection of virtual terminals, effectively reduce the workload of substation construction, and improve the design quality of virtual terminals.
Prototype electronics for the silicon pad layers of the future Forward Calorimeter (FoCal) of the ALICE experiment at the LHC
Authors: Bourrion O. , Tourres D. , Guernane R. , Arata C. , Bouly J.-L. , Ponchant N.
Published: April 2023

A Forward Calorimeter (FoCal) has been proposed as part of the ALICE upgrades for data
taking from 2029 onwards. The FoCal will feature a sampling electromagnetic calorimeter segmented
into 110 towers supplemented by a hadron calorimeter. The electromagnetic calorimeter will be
composed of 20 passive layers of tungsten absorber interleaved with 18 active layers of
low-granularity silicon pad sensors and two layers of high-granularity pixel detectors. Each pad
layer will be read out by 110 silicon pad sensors of 72 channels, amounting to a total of 1980
sensors.

This paper describes, from front-end to back-end, the electronics developed to instrument a tower
prototype composed of 18 silicon pad sensors as well as a design proposal for the full-detector
readout system.
Mapping global forest regeneration–an untapped potential to mitigate climate change and biodiversity loss
Authors: Ling Pui-Yu , Aguilar-Amuchastegui Naikoa , Baldwin-Cantello William , Rayden Tim , Gordon James , Dainton Stuart , Bagwill April L , Pacheco Pablo
Published: April 2023

Forest regeneration can be a low-cost solution to mitigate climate change, and mapping its extent can support global goals such as the Bonn Challenge, which set a goal to put 350 million hectares of degraded forests and landscapes into restoration by 2030. Our study combined multiple remote sensing datasets and expert surveys, identifying

55.7
±
6.2

million hectares of likely regenerated forests between 2000 and 2015 across areas that were not forested before 2000 and have remained forested from 2015 to 2018. The identified forest regeneration could potentially represent 22–25 billion young trees and a total biomass of about 3.2 billion tonnes. Forest regeneration took place in sites with less opportunity cost for agriculture for every country, but in more developed regions, forest regeneration took place in sites with higher suitability for cultivation. Expert feedback associated agricultural land use transitions and the establishment of protected areas, coupled with effective management and local support, as the key factors leading to successful forest regeneration. The results, publicly available, can facilitate discussions and help identify strategic locations to foster forest regeneration to achieve the global goals of mitigating climate change and restoring biodiversity.
Towards more inclusive and solution orientated community-based environmental monitoring
Authors: Mercer Louise , Whalen Dustin , Lim Michael , Cockney Kendyce , Cormier Shaun , Irish Charlotte , Mann Paul J
Published: April 2023

Rapid climate-driven environmental change continues to threaten front-line communities that rely on Arctic landscapes to sustain their way of life. Community-Based Monitoring (CBM) can increase our knowledge of environmental change and understanding of human-environment interactions occurring across the Arctic. However, the depth of CBM research outcomes have been limited by an imbalance in contributions from external researchers and community members. A detailed literature analysis revealed that the number of studies documenting CBM approaches in Inuit Nunangat (Inuit homeland in Canada) have increased over the last decade. We identify that bottom-up guiding protocols including the National Inuit Strategy on Research, has increased community engagement in Arctic research processes and equitable outcomes. However, these increases have been concentrated on wildlife-based research where consistent funding streams and pre-existing alignment with community priorities exist. To explore the potential for guiding principles to be more successfully incorporated into impactful CBM, we present a co-developed environmental CBM case study aiming to document and aid understanding of climate-driven landscape change near Tuktoyaktuk, Inuvialuit Settlement Region, Canada since 2018. A foundation of early dialogue and collaborative partnerships between community members and external researchers formed the basis of a community-based climate monitoring program driven by community research priorities. A succession of funded CBM projects at Tuktoyaktuk demonstrated that longer term and resilient climate monitoring can bring together Scientific and Indigenous knowledge systems. Progressing beyond an emphasis on data collection is vital to sustain monitoring efforts, capacity sharing and co-dissemination processes to ensure research is communicated back in a way that is understandable, relevant, and usable to address community priorities. The need for successful CBM is often at odds with current research funding structures, which risks a fragmented mosaic of early-stage initiatives focused on understanding environmental problems rather than sustained and progressive research development towards cooperative solutions.
Lattice Green/Neumann function for the 2D Laplacian operator defined on square lattice on cylinders, tori and other geometries with some applications
Authors: Malik Mamode
Published: April 2023

The lattice Green functions for the discrete planar Laplacian defined on regular square lattice wrapped around cylinders and tori are rigorously defined and obtained in an exact analytic form. The method of images well-known in potential theory is implemented to derive for many other geometries with free boundaries (semi-infinite or finite cylinders and strips, rectangle) the related exact lattice Green-Neumann functions needed to readily solve discrete Neumann problems or, via a Neumann-to-Dirichlet mapping, discrete Dirichlet problems for these flat square lattices. Some applications are thus proposed as explicit expressions of two-point resistances for related resistor networks, and some probability-based characteristics regarding the associated Pòlya’s random walks.
Growing human-scale scala tympani-like in vitro cell constructs
Authors: Aregueta Robles Ulises A , Bartlett-Tomasetig Florence , Poole-Warren Laura A
Published: April 2023

Emerging materials and electrode technologies have potential to revolutionise development of higher resolution next-generation, bionic devices. However, barriers associated with the extended timescales, regulatory constraints, and opportunity costs of preclinical and clinical studies, can inhibit such innovation. Development of in vitro models that mimic human tissues would provide an enabling platform to overcome many of these barriers in the product development pathway. This research aimed to develop human-scale tissue engineered cochlea models for high throughput evaluation of cochlear implants on the bench. Novel mould-casting techniques and stereolithography three-dimensional (3D) printing approaches to template hydrogels into spiral-shaped structures resembling the scala tympani were compared. While hydrogels are typically exploited to support 3D tissue-like structures, the challenge lies in developing irregular morphologies like the scala tympani, in which the cochlear electrodes are commonly implanted. This study successfully developed human-scale scala tympani-like hydrogel structures that support viable cell adhesion and can accommodate cochlear implants for future device testing.
DART impact ejecta gave Dimorphos an extra push
Authors: Cooper Keith
Published: April 2023

Research has found that the impact of a spacecraft into the asteroid Dimorphos last year changed the asteroid’s orbital period around its larger companion asteroid by 33 minutes.
New type of fractal emerges in spin ices
Authors: Dumé Isabelle
Published: April 2023

A new type of fractal has appeared unexpectedly in a class of magnets known as spin ices, seeming to emerge from excitations of magnetic monopoles in the material.
Event horizon can destroy quantum states
Authors: Kwan Jacklin
Published: April 2023

A thought experiment reveals that black holes should annihilate nearby quantum superpositions, as Jacklin Kwan finds out.
Science needs reform to tackle racism, says report
Authors: Blaustein Richard
Published: April 2023

A new report from the US National Academies of Sciences, Engineering and Medicine (NASEM) says that US educational institutions and workplaces must be pro-active in combatting racism and supporting people from minority groups.
Exploiting physics to impact the economy
Authors: Durrani Matin
Published: April 2023

Anne Crean, head of science and innovation at the Institute of Physics, talks to Matin Durrani about how it is supporting research and business innovation.
Magnificent structures
Authors: Crease Robert P
Published: April 2023

Protecting science requires not just science, but an understanding of human behaviour too, argues Robert P Crease.
Deconstructing structures
Authors: Wade Jess
Published: April 2023

Jess Wade reviews Nuts and Bolts: Seven Small Inventions That Changed the World (in a Big Way) by Roma Agrawal.
Where’s Wally in the multiverse?
Authors: Berney John
Published: April 2023

John Berney comes to the shocking conclusion that Wally may never exist either in our universe or any other.
The fundamental solution to \Box_{𝑏} on quadric manifolds with nonzero eigenvalues
Authors: Boggess Albert , Raich Andrew
Published: April 2023

This paper is part of a continuing examination into the geometric and analytic properties of the Kohn Laplacian and its inverse on general quadric submanifolds of

C

n

×

C

m

\mathbb {C}^n\times \mathbb {C}^m

. The goal of this article is explore the complex Green operator in the case that the eigenvalues of the directional Levi forms are nonvanishing. We (1) investigate the geometric conditions on

M
M

which the eigenvalue condition forces, (2) establish optimal pointwise upper bounds on complex Green operator and its derivatives, (3) explore the

L
p

L^p

and

L
p

L^p

-Sobolev mapping properties of the associated kernels, and (4) provide examples.
Dimensionality reduction and visualization of single-cell RNA-seq data with an improved deep variational autoencoder
Authors: Jiang Jing , Xu Junlin , Liu Yuansheng , Song Bosheng , Guo Xiulan , Zeng Xiangxiang , Zou Quan
Published: April 2023

Single-cell RNA sequencing (scRNA-seq) is a revolutionary breakthrough that determines the precise gene expressions on individual cells and deciphers cell heterogeneity and subpopulations. However, scRNA-seq data are much noisier than traditional high-throughput RNA-seq data because of technical limitations, leading to many scRNA-seq data studies about dimensionality reduction and visualization remaining at the basic data-stacking stage. In this study, we propose an improved variational autoencoder model (termed DREAM) for dimensionality reduction and a visual analysis of scRNA-seq data. Here, DREAM combines the variational autoencoder and Gaussian mixture model for cell type identification, meanwhile explicitly solving ‘dropout’ events by introducing the zero-inflated layer to obtain the low-dimensional representation that describes the changes in the original scRNA-seq dataset. Benchmarking comparisons across nine scRNA-seq datasets show that DREAM outperforms four state-of-the-art methods on average. Moreover, we prove that DREAM can accurately capture the expression dynamics of human preimplantation embryonic development. DREAM is implemented in Python, freely available via the GitHub website, https://github.com/Crystal-JJ/DREAM.
Abrocitinib as a novel treatment for lichen sclerosus
Authors: Bao Chengbei , Xu Qiuyun , Xiao Zhixun , Wang Haiqing , Luo Renwei , Cheng Bo , Ji Chao , Gong Ting
Published: April 2023

Ten patients were recruited to evaluate the efficacy and safety of abrocitinib for the treatment of lichen sclerosus (LS). All patients reported rapid control of pruritus at week 2 and achieved Investigator’s Global Assessment 0 or 1 at week 12. This study suggests that the abrocitinib could be an effective and safe treatment option for LS, based on the significant improvements seen in investigator evaluations, patient-reported outcomes and skin imaging findings.
Granulomatous tattoo reaction treated with topical allopurinol
Authors: Moreno-Casas Guillermo , Pereira-González Antonio , Rodríguez-Nevado Isabel , Rubio-Fernández Alejandro , Chaves-Álvarez Antonio
Published: April 2023

Granulomatous reactions to tattoo ink have been frequently associated with exogenous pigment, although sometimes they are the manifestation of a cutaneous or an underlying systemic sarcoidosis. We report a case of a patient with a granulomatous reaction to a black tattoo pigment treated with 3% topical allopurinol for 3 months. We observed complete resolution without any side-effects. Examination and follow-up ruled out sarcoidosis. Oral allopurinol has been proven to be effective for the management of granulomatous reactions to tattoos. Based on the significant improvement we have described in our patient, we recommend new studies to reveal all the potential benefits of the topical use of allopurinol for the treatment of granulomatous reactions to tattoo ink.
Tracking the temporal dynamics of the face-like inversion effect as revealed by Chinese characters using magnetoencephalography
Authors: Li Chun-Hui , Wang Man-Ying , Kuo Bo-Cheng
Published: April 2023

The neural basis of configural processing has been extensively studied by exploiting face inversion during recognition, and growing evidence has revealed that word inversion also involves changes in configuration. However, the neural dynamics of face-like inversion effects remain unclear. Here, we tracked the temporal dynamics of neural responses that were sensitive to inversion during Chinese character recognition as they occurred during face recognition using multivariate decoding and temporal generalization analyses. We recorded magnetoencephalography while participants performed a one-back task for faces, compound characters, and simple characters with upright and inverted orientations. We showed that the inversion effect (inverted versus upright) can be decoded at occipitotemporal sensors for all stimulus types over and across time points, with a stronger impact on faces and compound characters than on simple characters. The inversion effect occurred earlier and lasted longer for faces than for characters, and the effect was also stronger for compound characters than for simple characters. Finally, we demonstrated inversion effects in the event-related field for all stimulus types and identified their sources in the ventral occipitotemporal areas. Overall, this study provides novel evidence for the temporal dynamics of the face-like inversion effect occurring during Chinese character recognition.
Epidemiology of Suspected and Confirmed Acute Hepatitis E Cases Reported Among Los Angeles County Residents, 2017–2019
Authors: Lautredou Cassandra C , Dao Bonnie , Gounder Prabhu
Published: April 2023

In a 3-year period, 38 of 48 persons testing positive for hepatitis E virus (HEV) immunoglobulin M in Los Angeles County did not meet the acute HEV case definition. Healthcare providers should restrict HEV serologic testing for persons with clinically compatible symptoms or epidemiologic risk factors.
Genetic variance and indirect genetic effects for affiliative social behavior in a wild primate
Authors: McLean Emily M , Moorad Jacob A , Tung Jenny , Archie Elizabeth A , Alberts Susan C
Published: April 2023

Affiliative social behaviors are linked to fitness components in multiple species. However, the role of genetic variance in shaping such behaviors remains largely unknown, limiting our understanding of how affiliative behaviors can respond to natural selection. Here, we employed the “animal model” to estimate environmental and genetic sources of variance and covariance in grooming behavior in the well-studied Amboseli wild baboon population. We found that the tendency for a female baboon to groom others (“grooming given”) is heritable (h2 = 0.22 ± 0.048), and that several environmental variables—including dominance rank and the availability of kin as grooming partners—contribute to variance in this grooming behavior. We also detected small but measurable variance due to the indirect genetic effect of partner identity on the amount of grooming given within dyadic grooming partnerships. The indirect and direct genetic effects for grooming given were positively correlated (r = 0.74 ± 0.09). Our results provide insight into the evolvability of affiliative behavior in wild animals, including the possibility for correlations between direct and indirect genetic effects to accelerate the response to selection. As such they provide novel information about the genetic architecture of social behavior in nature, with important implications for the evolution of cooperation and reciprocity.
Tackling the Pangenome Dilemma Requires the Concerted Analysis of Multiple Population Genetic Processes
Authors: Baumdicker Franz , Kupczok Anne
Published: April 2023

The pangenome is the set of all genes present in a prokaryotic population. Most pangenomes contain many accessory genes of low and intermediate frequencies. Different population genetics processes contribute to the shape of these pangenomes, namely selection and fitness-independent processes such as gene transfer, gene loss, and migration. However, their relative importance is unknown and highly debated. Here, we argue that the debate around prokaryotic pangenomes arose due to the imprecise application of population genetics models. Most importantly, two different processes of horizontal gene transfer act on prokaryotic populations, which are frequently confused, despite their fundamentally different behavior. Genes acquired from distantly related organisms (termed here acquiring gene transfer) are most comparable to mutation in nucleotide sequences. In contrast, gene gain within the population (termed here spreading gene transfer) has an effect on gene frequencies that is identical to the effect of positive selection on single genes. We thus show that selection and fitness-independent population genetic processes affecting pangenomes are indistinguishable at the level of single gene dynamics. Nevertheless, population genetics processes are fundamentally different when considering the joint distribution of all accessory genes across individuals of a population. We propose that, to understand to which degree the different processes shaped pangenome diversity, the development of comprehensive models and simulation tools is mandatory. Furthermore, we need to identify summary statistics and measurable features that can distinguish between the processes, where considering the joint distribution of accessory genes across individuals of a population will be particularly relevant.
Therapeutic Potential of Human Intestinal Organoids in Tissue Repair Approaches in Inflammatory Bowel Diseases
Authors: Rutherford Duncan , Ho Gwo-Tzer
Published: April 2023

Inflammatory bowel diseases (IBDs) are chronic immune-mediated conditions characterized by significant gut tissue damage due to uncontrolled inflammation. Anti-inflammatory treatments have improved, but there are no current prorepair approaches. Organoids have developed into a powerful experimental platform to study mechanisms of human diseases. Here, we specifically focus on its role as a direct tissue repair modality in IBD. We discuss the scientific rationale for this, recent parallel advances in scientific technologies (CRISPR [clustered regularly interspaced short palindromic repeats]/Cas9 and metabolic programming), and in addition, the clinical IBD context in which this therapeutic approach is tractable. Finally, we review the translational roadmap for the application of organoids and the need for this as a novel direction in IBD.
Residential Clustering of Coronavirus Disease 2019 Cases and Efficiency of Building-Wide Compulsory Testing Notices as a Transmission Control Measure in Hong Kong
Authors: Young Benjamin R , Yang Bingyi , Wu Peng , Adam Dillon C , Wong Jessica Y , Ho Faith , Gao Huizhi , Lau Eric H Y , Leung Gabriel M , Cowling Benjamin J
Published: April 2023

We described the frequency of residential case clusters and the efficiency of compulsory testing in identifying cases using buildings targeted in compulsory testing and locally infected coronavirus disease 2019 (COVID-19) cases matched by residence in Hong Kong. Most of the buildings (4246 of 7688, 55.2%) with COVID-19 cases identified had only 1 reported case, and 13% of the daily reported cases were detected through compulsory testing. Compulsory testing notices could be essential in attempting to eliminate infections (“zero COVID”) and have an impact early in an epidemic, but they appear to be relatively inefficient in response to sustained community transmission.
Vaccine Effectiveness Against Severe Acute Respiratory Syndrome Coronavirus 2 Delta and Omicron Infection and Infectiousness Within Households in the Netherlands Between July 2021 and August 2022
Authors: Hoeve Christina E , de Gier Brechje , Huiberts Anne J , de Melker Hester E , Hahné Susan J M , van den Hof Susan , Knol Mirjam J
Published: April 2023

Background

We aimed to estimate vaccine effectiveness against infection (VE-infection) and against further transmission (VE-infectiousness) in a household setting during Delta and Omicron. Knowing these effects can aid policy makers in deciding which groups to prioritize for vaccination.

Methods

Participants with a positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) test were asked about coronavirus disease 2019 (COVID-19) vaccination status and SARS-CoV-2 testing of their household members 1 month later. VE-infection and VE-infectiousness were estimated using generalized estimating equation logistic regression adjusting for age, vaccination status, calendar week, and household size.

Results

A total of 3399 questionnaires concerning 4105 household members were included. During the Delta period, VE-infection and VE-infectiousness of primary series were 47% (95% confidence interval [CI], −27% to 78%) and 70% (95% CI, 28% to 87%), respectively. During the Omicron period, VE-infection was −36% (95% CI, −88% to 1%) for primary series and −28% (95% CI, −77% to 7%) for booster vaccination. VE-infectiousness was 45% (95% CI, −14% to 74%) for primary series and 64% (95% CI, 31% to 82%) for booster vaccination.

Conclusions

Our study shows that COVID-19 vaccination is effective against infection with SARS-CoV-2 Delta and against infectiousness of SARS-CoV-2 Delta and Omicron. Estimation of VE against infection with SARS-CoV-2 Omicron was limited by several factors. Our results support booster vaccination for those in close contact with vulnerable people to prevent transmission.
Regional and national antimicrobial stewardship activities: a survey from the Joint Programming Initiative on Antimicrobial Resistance—Primary Care Antibiotic Audit and Feedback Network (JPIAMR-PAAN)
Authors: Michalsen Benedikte Olsen , Xu Alice X T , Alderson Sarah L , Bjerrum Lars , Brehaut Jamie , Bucher Heiner C , Clarkson Janet , Duncan Eilidh , Grimshaw Jeremy , Gunnarsson Ronny , Høye Sigurd , Ivers Noah , Lecky Donna M , Lindbæk Morten , Llor Carl , Lundgren Pia Touboul , O’connor Denise , Pulcini Celiné , Ramsay Craig , Sundvall Pär-Daniel , Verheij Theo , Schwartz Kevin L ,   JPIAMR-PAAN, Acampora Anna , Alderson Sarah L , Coello Pablo Alonso , Altiner Attila , Bjerrum Lars , Brehaut Jamie , Brown Benjamin , Bucher Heiner C , Butler Chris , Cavazzuti Laura , Clarkson Janet , Davoli Marina , De Sutter An , Martino Mirko Di , Duncan Eilidh , Francis Nick , Grilli Roberto , Grimshaw Jeremy , Gunnarsson Ronny , Hallsworth Michael , Hemkens Lars , Hoye Sigurd , Ivers Noah , Khan Tasneem , Lecky Donna M , Lindbaek Morten , Linder Jeff , Little Paul , Llor Carl , Lorencatto Fabiano , O’connor Denise , Pulcini Celine , Ramsay Craig , Saulle Rosella , Schwartz Kevin L , Simon Maia , Sundvall Pär-Daniel , Taljaard Monica , Lundgren Pia Touboul , Vellinga Akke , Verbakel Jan , Verheij Theo
Published: April 2023

Background

Antibiotic overuse and misuse in primary care are common, highlighting the importance of antimicrobial stewardship (AMS) efforts in this setting. Audit and feedback (A&F) interventions can improve professional practice and performance in some settings.

Objectives and methods

To leverage the expertise from international members of the Joint Programming Initiative on Antimicrobial Resistance – Primary care Antibiotic Audit and feedback Network (JPIAMR-PAAN). Network members all have experience of designing and delivering A&F interventions to reduce inappropriate antibiotic prescribing in primary care settings. We aim to introduce the network and explore ongoing A&F activities in member regions. An online survey was administered to all network members to collect regional information.

Results

Fifteen respondents from 11 countries provided information on A&F activities in their country, and national/regional antibiotic stewardship programmes or policies. Most countries use electronic medical records as the primary data source, antibiotic appropriateness as the main outcome of feedback, and target GPs as the prescribers of interest. Funding sources varied across countries, which could influence the frequency and quality of A&F interventions. Nine out of 11 countries reported having a national antibiotic stewardship programme or policy, which aim to provide systematic support to ongoing AMS efforts and aid sustainability.

Conclusions

The survey identified gaps and opportunities for AMS efforts that include A&F across member countries in Europe, Canada and Australia. JPIAMR-PAAN will continue to leverage its members to produce best practice resources and toolkits for antibiotic A&F interventions in primary care settings and identify research priorities.
Manifold lifting: scaling Markov chain Monte Carlo to the vanishing noise regime
Authors: Au Khai Xiang , Graham Matthew M , Thiery Alexandre H
Published: April 2023

Standard Markov chain Monte Carlo methods struggle to explore distributions that concentrate in the neighbourhood of low-dimensional submanifolds. This pathology naturally occurs in Bayesian inference settings when there is a high signal-to-noise ratio in the observational data but the model is inherently over-parametrised or nonidentifiable. In this paper, we propose a strategy that transforms the original sampling problem into the task of exploring a distribution supported on a manifold embedded in a higher-dimensional space; in contrast to the original posterior this lifted distribution remains diffuse in the limit of vanishing observation noise. We employ a constrained Hamiltonian Monte Carlo method, which exploits the geometry of this lifted distribution, to perform efficient approximate inference. We demonstrate in numerical experiments that, contrarily to competing approaches, the sampling efficiency of our proposed methodology does not degenerate as the target distribution to be explored concentrates near low-dimensional submanifolds. Python code reproducing the results is available at https://doi.org/10.5281/zenodo.6551654.