bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling the oxygen effect in DNA strand break induced by gamma-rays with TOPAS-nBio
Authors: D-Kondo Naoki , Masilela Thongchai A M , Shin Wook-Geun , Faddegon Bruce , LaVerne Jay , Schuemann Jan , Ramos-Mendez Jose
Published: October 2024

Objective. To present and validate a method to simulate from first principles the effect of oxygen on radiation-induced double-strand breaks (DSBs) using the Monte Carlo Track-structure code TOPAS-nBio. Approach. Two chemical models based on the oxygen fixation hypothesis (OFH) were developed in TOPAS-nBio by considering an oxygen adduct state of DNA and creating a competition kinetic mechanism between oxygen and the radioprotective molecule WR-1065. We named these models ‘simple’ and ‘detailed’ due to the way they handle the hydrogen abstraction pathways. We used the simple model to obtain additional information for the •OH–DNA hydrogen abstraction pathway probability for the detailed model. These models were calibrated and compared with published experimental data of linear and supercoiling fractions obtained with R6K plasmids, suspended in dioxane as a hydroxyl scavenger, and irradiated with 137Cs gamma-rays. The reaction rates for WR-1065 and O2 with DNA were taken from experimental works. Single-Strand Breaks (SSBs) and DSBs as a function of the dose for a range of oxygen concentrations [O2] (0.021%–21%) were obtained. Finally, the hypoxia reduction factor (HRF) was obtained from DSBs. Main Results. Validation results followed the trend of the experimental within 12% for the supercoiled and linear plasmid fractions for both models. The HRF agreed with measurements obtained with 137Cs and 200–280 kVp x-ray within experimental uncertainties. However, the HRF at an oxygen concentration of 2.1% overestimated experimental results by a factor of 1.7 ± 0.1. Increasing the concentration of WR-1065 from 1 mM to 10–100 mM resulted in a HRF difference of 0.01, within the 8% statistical uncertainty between TOPAS-nBio and experimental data. This highlights the possibility of using these chemical models to recreate experimental HRF results. Significance. Results support the OFH as a leading cause of oxygen radio-sensitization effects given a competition between oxygen and chemical DNA repair molecules like WR-1065.
The health status assessment method and practice of emergency diesel generator system in nuclear power plant based on deterioration degree
Authors: Qing Chen , Cheng Bin , Yang Xiaohu
Published: October 2024

Due to the complexity of the emergency diesel generator (EDG) system in nuclear power plants and the lack of detailed equipment-level health status assessment models, this article introduces a deterioration-based system health status assessment method. Taking the large and complex EDG system as a pilot, the method combines monitoring data and maintenance information of the EDG to achieve dynamic assessment of the health status of the EDG system at the equipment level. This provides guidance for predicting and repairing faults of EDGs in nuclear power plants. Additionally, this method can be extended to other large and complex systems.
Comprehensive monitoring system for high voltage cables based on the ground current signal of the cable metal sheath
Authors: Gan Yusen , Li Wenxin , Chen Guojin , Xie Wei , Xia Xin , Cui Fuxing , Zhang Dongqi , Fang Weixing
Published: October 2024

This paper has presented a comprehensive monitoring system for high voltage cables based on the ground current signal of the cable metal sheath. The system can collect and process the power frequency AC current and three high-frequency partial discharge signals in real time synchronously, which realize the synchronous detection of leakage current, relative dielectric loss, harmonic, partial discharge, and improve the integration of the hardware system.
Active damping control based bus voltage resonance suppression in electrolytic capacitorless PMSM application
Authors: Cheng Xin , Yao Lei , Han Ping , Zhou Rougang , Zhu Junjie
Published: October 2024

The structure of electrolytic capacitorless in automotive electronic applications has the advantages of lower cost and better reliability. However, motor drive systems using this structure may experience unstable bus voltage. To this end, this paper proposes an active damping control strategy based on virtual impedance. By modelling the electric drive system and conducting stability analysis, the cause of bus voltage resonance due to the use of small capacitors is revealed. Based on the extracted DC bus voltage harmonic signal, additional voltage vectors are added in the d-axis and q-axis voltage vectors, eliminating the impedance mismatch problem in the drive system caused by the reduction of bus capacitance, effectively suppressing the voltage oscillation on the machine side of the drive system. Simulation data shows that under the condition of using small-capacity ceramic capacitors, the method proposed in this paper achieves a harmonic suppression capability similar to that of large-capacity electrolytic capacitors, effectively ensuring the application safety of automotive drivers with electrolytic capacitorless architecture.
Energy management method for battery swapping station combining reinforcement learning and mathematical optimization
Authors: Yue Shuaixian , Li Liang , Su Yongxin
Published: October 2024

The rapid proliferation of electric vehicles has spurred the expansion of scalable Battery Swapping Station (BSS) to cater to the demand for swift charging. However, the current energy management faces challenges in coping with the fluctuation of charging batteries in scalable BSS, the unpredictability of electricity prices and battery demand, as well as the intricacy of demand response. So, this paper presents a two-layer optimization framework for energy management in scalable BSS. The framework decomposes the power scheduling problem in BSS into two subproblems and solves them with deep reinforcement learning and mathematical optimization. The upper layer uses deep reinforcement learning to schedule the BSS’s total power, while the lower layer uses mathematical optimization to allocate the power to each charging pile. The two layers cooperate to achieve an efficient solution. The experiments demonstrate that the proposed method can reduce the operating cost of the BSS, satisfy the safety and user’s demand, and facilitate grid demand response, in BSSs of different sizes. The method is an effective solution for power scheduling of scalable BSS.
Simulation analysis and optimization of thermoelectric refrigeration and air conditioning
Authors: Zhang Chunqiang , Chen Mengxue , Ge Chang , Yu Suihuai
Published: October 2024

Thermoelectric refrigeration technology is mainly through the Peltier effect to achieve refrigeration, thermoelectric refrigeration air conditioning needs to be combined with a certain air flow rate to realize the separation of cold and heat, and make full use of the cold end to realize the refrigeration function, or else the refrigeration efficiency is seriously affected. Based on the ICEPAK simulation platform of ANSYS, we analyze the influence of structure and parameter settings on the conversion efficiency of thermoelectric refrigeration air conditioning fan under the established boundary conditions, establish the relationship between air flow rate and temperature drop value, and put forward the optimization of the product structure design scheme, and the results of the optimization scheme show that there is a peak in the operating current at a certain heat dissipation efficiency; and lengthening the length of the air ducts through the optimization of the structure can enhance the refrigeration effect of the air conditioner.
Temperature characteristics of the two phase mechanically pumped cooling circuit
Authors: Chen Hao , Dai Shugang , Gong Ao , Xie Lei
Published: October 2024

To meet the cooling requirements of high thermal consumption equipments, the two phase mechanically pumped cooling circuit was designed and fabricated. The refrigerant was driven by a mechanical pump and the heat was transmitted between the evaporator and condenser in this process. Experiments were conducted to analyze the influence of the refrigerant flow velocity and heat flux on the temperature characteristics of the cooling circuit. In addition, the simulation results and experimental results were compared to confirm the reliability of the simulation results. The results showed that the circuit can efficiently cool the heat sources with a heat flux of 250W/cm2. The difference in temperature between the entrance and exit of the evaporator is within 5°C while the refrigerant flow velocity is 0.5L/min, and the velocity needs to be 1.4L/min while water is media.
The design and implementation of a smart greenhouse control system
Authors: Zhou Dengrong
Published: October 2024

Against the dual backdrop of continuously improving agricultural production levels and the global scarcity of water resources, countries worldwide are actively exploring the topic of water conservation. The development of an intelligent irrigation control system could make a significant contribution to water conservation efforts, while also helping to increase crop yields. This project adopts a modular design approach, utilizing sensors to collect real-time environmental data surrounding the crops. If the data falls outside the predefined optimal range for crop growth, the system automatically initiates irrigation, cooling, and supplemental lighting. The hardware design primarily consists of a data perception module and a control terminal module. After testing, the system runs stably and can accurately obtain information such as soil moisture, light intensity and ambient temperature, and basically realize the digital intelligent control of crop growing environment.
Research on the characteristics of a pneumatic proportional valve
Authors: Huang Yong , Yu Liangyao
Published: October 2024

The execution of autonomous driving in heavy-duty trucks necessitates stringent regulation of their braking torque output. Hydraulic retarder serves as a widely auxiliary braking system in heavy-duty vehicles, with the pneumatic proportional valve functioning as the core component of its control system, regulating the output response and control precision of the braking torque of the hydraulic retarder. To improve the accuracy of brake torque control for hydraulic retarders, it is critical to conduct thorough research on the control system, especially the pneumatic proportional valve. Therefore, A detailed analysis of the working mechanism of pneumatic proportional valves was conducted, encompassing the construction of mathematical and simulation models. The efficacy of the simulation model was confirmed via experimental validation. When the control pressure increases, the simulation results are close to the experimental results, with a maximum discrepancy of 18%; when the control pressure decreases, the simulation results show a similar trend to the experimental results. The research can aid in formulating control methodologies for pneumatic proportional valves and offer theoretical guidelines for future exploration into boosting the precision of hydraulic retarder braking torque control.
Research on improving the automatic stability of trimming unit
Authors: Zhang Nan , Shi Yiqing , Zhang Hao , Liu Qingsheng , Yao Hongliang , Yuan Chao , Jiang Yinzhen
Published: October 2024

Due to the influence of temperature and other factors in the forming of forgings, the shape of the forging fringe is often challenging to control and predict, which restricts the operation of forging automation. In this paper, the forging position is detected by the vision means, which is conductive to identify whether the production process is normal or not to avoid the loss caused by the interruption of the production unit. Meanwhile, for the forging temperature changes on visual recognition, the relationship curve between forging temperature and exposure time is determined by statistical method, so that the temperature of the forging regulate the visual camera exposure time to improve the accuracy of visual recognition.
Design and technological analysis of the multi-position progressive die for the clamp
Authors: Liang Haicheng , Song Lihua , Kang Junyuan
Published: October 2024

The technological process of the clamp part is analyzed, the design of the stamping and bending process for the clamp is introduced, including determination of the operation sequence and operation position parts dimensions. The process is used side blade settles to distance, pilot pin was used in exact positioning, the blanking and bending of the part were carried out continuously. The design of the general structure, layout of the progressive and forming characteristics die for the clamp is introduced in detail, the method for designing and calculating the key parts.
Design improvement of interference-type locking cylinder
Authors: Zhang Junli , Lu Baochun , Zhang Honghu , Yao Jiachen , Li Zhengyang
Published: October 2024

The wear of the cylinder and locking-sleeve, generate during operation, is one of the main problems of interference-locking cylinder. In order to solve this problem, the operating principle and traditional design method of interference-locking cylinder are introduced briefly, the causes of wear are found based on its force state. And then an improved design method of interference-locking cylinder is proposed, the magnitude of interference is divided into two parts. A simplified finite element model of interference-fit is established and simulations are conducted to verify the effectiveness of the improved design method, the results indicate that the improved design method reduces the wear of the cylinder and locking-sleeve, and also can improve the service life of the interference-locking cylinder.
Influence of input parameters on the measurement accuracy of external clamp-on ultrasonic flowmeters: An experimental study
Authors: Yang Zhongzhi , Yu Chunyang , Gan Quanlu , Yang Hongjie , Liu Xing
Published: October 2024

This study comprehensively evaluated the performance of clamp-on ultrasonic gas flowmeters at a natural gas field. The research focused on the influence of key input parameters on flow measurement accuracy during practical application of the instrument and proposed specific measures to improve measurement results. It was found that errors in outer diameter and wall thickness not only lead to flow calculation inaccuracies but also directly impact the propagation path of ultrasonic waves. Therefore, accurate input parameters are crucial to ensure precise flow results. Additionally, the study revealed that changes in installation distance have minimal effects on flow measurement results and adjustments can be made as needed to obtain better signal parameters. Variations in input temperature and pressure mainly affect the conversion coefficient from operating conditions to standard conditions, with minor impacts on flow velocity and operating flow rate. Thus, the velocity ratio method can be considered during on-site calibration to mitigate the effects of temperature and pressure changes.
Research on the calibration method of winding deformation tester
Authors: Sun Xiaojie , Gao Zhishang , Chen Qian , Liu Xiao , Deng Bing , He Qingyu , Wang Dalong
Published: October 2024

The focus of this paper is the calibration method and process for winding deformation tester, encompassing its working principle, metrological characteristics, calibration conditions and measurement methods. The calibration conditions are divided into environmental conditions and measurement standards and other equipments. The measurement methods are divided into indication error of scanning frequency and indication error of amplitude ratio. The key steps in the calibration process are elaborated, including the selection of standard equipments, error analysis, data processing. The method’s feasibility is verified through experiments.
An analytical solution to “pillowing effect” for composite fuselages
Authors: Feng Jianwen , Li Chenlai , Xiao Zhengxing
Published: October 2024

“Pillowing effect”, introduced by inner cabin air pressure on stringer-frame stiffened fuselage cylinder, is a critical loading case for civil aircraft fuselage. The “pillowing effect” causes out-of-plane bending and shear to fuselage panels, which is a rather huge load for such membrane structures. The fuselage’s longitudinal load and bending load interact nonlinearly with each other in a so called “beam-column” formation, invalidating the superposition principle for linear elasticity. An analytical solution to the axisymmetric “beam-column” model is given in this study to account for the “pillowing effect” of orthotropic composite fuselages. This formula can be employed to perform stress checks against “pillowing effect” during fuselage design.
Study on binders and pore-forming agents on properties of SiCp particulates preforms
Authors: Yu Yingwei , Wang Xinwen , Liu Wangzi , Jiang Jun , Xiao Weijun
Published: October 2024

The effects of the content of the starch, stearic acid, or graphite and binder (sodium metasilicate) on the microstructure, volume fraction, porosity, dimension of the SiCp preforms, and compressive strength were studied. Two methods were used to fabricate the SiCp preforms, that is, SiCp preforms by using the binders of sodium metasilicate or not, respectively, and were calcined in air. The results show that the SiCp preforms were fabricated with starch, stearic acid and graphite as pore-forming agents, which the volume fraction can exceed 54%; used graphite which volume fraction can reach a maximum of 56.2%; After sintered, the dimension of SiCp performs is in the range of 2.9%∼3.2%; The compressive strength of SiCp performs with the binders of sodium metasilicate can reach 35Mpa.
Multisource partial domain adaptation for bearing fault diagnosis
Authors: Wang Minghui , Chen Yuhang , Xiao Lei
Published: October 2024

Domain adaptation has been widely used in fault diagnosis and dealt with data distribution discrepancies, but the labels in source and target domains are usually assumed to be identical. The complexity of the working conditions, in reality, leads to the fact that the labels in target domains are often a subset of the labels in source domains. This special case is called the partial domain problem. However, most of the existing proposed methods for solving partial domain problems are limited to single-source-domain scenarios and fail to effectively integrate multisource knowledge. Hence, this study proposes a new approach of multisource domain obfuscation-subdomain alignment (MSDO-SA) for partial domain adaptation fault diagnosis in multisource domains. Through domain obfuscation, the multisource domains are converted into a single source domain. The subdomain alignment aims at improving the generalization ability and relevance of the model, and effectively alleviates the domain shift problem. Finally, multiple partial domain fault diagnosis tasks using the CWRU dataset validate the effectiveness, robustness, and superiority of the proposed method.
A remaining useful life prediction method based on DATCN-PSOSEN for turbofan engines
Authors: Fan Yijing , Han Dongyang , Hong Ge , Wang Yu , Zhang Fengqi , Xia Tangbin
Published: October 2024

Turbofan engine is a crucial operational component of aircraft. Remaining useful life (RUL) prediction is important for the stable and reliable operation of the turbofan engine. High-dimensional and large-capacity monitoring data of turbofan engines pose a considerable challenge to accurate RUL prediction. A novel approach based on dual-attention temporal convolutional network (DATCN) and particle swarm optimization with selective ensemble (PSOSEN) is proposed in this paper. In the first stage, DATCN is utilized to explore the internal correlations among various input features and different time steps in monitoring data, highlighting the degradation information from two dimensions. In the second stage, PSOSEN is developed to prune base models, excluding the ones with poor performance and assigning varying weights to the others, leading to selectively ensembled prediction results. The experimental results on the C-MAPSS aero-engine degradation dataset validate the effectiveness of the proposed DATCN-PSOSEN method and show improvements of RUL prediction accuracy by 14.2% compared with other methods.
Unsupervised motor incipient fault detection using lightweight network and orthogonal low-rank embedding
Authors: Han Jinrui , Chen Zhen , Pan Ershun
Published: October 2024

Electrical motor is a key component in industrial systems. Detecting incipient fault of motor is critical to system reliability. However, the characteristics of faults and normal stages are difficult to distinguish, Meanwhile, the lightweight requirements of the model and the imbalance of the samples also make incipient fault detection challenged. To address these problems, this paper proposes an unsupervised fault detection method combines lightweight network and orthogonal low-rank embedding (OLE). The raw signals are firstly transformed into time-frequency images and fed into lightweight convolution network for feature extraction. Then, the features are clustered into orthogonal subspaces to enhance inter-class separability. Finally, a detection module based on distance metric is designed to identify the incipient fault of motor. The effectiveness of the proposed method is validated on four industrial motor dataset and compared with other methods.
PVDF/NiFe2O4 multiferroic composite membranes for dual mechanical and magnetic energy harvesting devices
Authors: Kieu Quang-Linh , Duong Thanh-Tung , Bui Thi-Hang , Nguyen Van-Quy , Yoon Soon-Gil , Tran Van-Dang
Published: October 2024

A multiferroic composite membrane, combining PVDF piezoelectric polymer and nickel ferrite (NFO) nanofibers, was successfully fabricated and studied as an active material layer in multifunctional devices designed to harvest both mechanical and magnetic energy. Optimization of the manufacturing process ensured an even distribution of NFO fibers within the PVDF matrix, enhancing the crystallization of PVDF in the electroactive β phase. The resulting PVDF/NFO multiferroic films exhibited both piezoelectric and magnetic properties, along with a pronounced magnetoelectric (ME) effect. In a structure comprising Al/PVDF-NFO/PDMS/Al, the device operated as a piezoelectric generator (PEG) under a pressing force of 0.5 MPa, achieving a maximum output power density of 14.7 μW cm−12 with a peak-to-peak voltage of 12.2 V. When subjected to an AC magnetic field of 20 Oe at 50 Hz, the device functioned as a magneto-mechano-electrical (MME) generator, producing a sinusoidal waveform voltage of 486 mV. The cost-effective and easily integrable PVDF/NFO composite membrane presents promising opportunities for developing flexible, self-powered smart sensors for human health monitoring systems and implantable biomedical devices.
On Rankin-Cohen brackets of Hecke eigenforms and modular forms of half-integral weight
Authors: Choie YoungJu , Kohnen Winfried , Zhang Yichao
Published: October 2024

We generalize the linear relation formula between the square of normalized Hecke eigenforms of weight

k
k

and normalized Hecke eigenforms of weight

2
k

2k

, to Rankin-Cohen brackets of general degree. As an ingredient of the proof, we also generalize a formula of Zagier on the Petersson inner product of Rankin-Cohen brackets involving Eisenstein series.
Conclusions
Authors: Hammel Alice M , Yee Roberta L
Published: October 2024

Regardless of the specific challenge or difference, there are some global strategies that work for all students with differences and disabilities. Our preparation for each encounter with them, in part, determines the level of success we have during our teaching opportunities.
Optimizing Safety and Precision for Secondary Liposuctions: Integrating Intraoperative Ultrasound With VASER Technology
Authors: Tambasco Damiano , Hoyos Alfredo , Perez Mauricio , Tomaselli Federica , Mir Jordi , Albanese Roberta
Published: October 2024

Background

Liposuction has gained significant popularity, leading to increased demand for secondary procedures due to complications such as scars and fibrosis that affect aesthetic outcomes. High-definition liposuction has emerged as a preferred technique, but the presence of fibrosis from previous surgeries may limit its effectiveness.

Objectives

The aim of this study was to explore the application of ultrasound (US)-assisted VASER (vibration amplification of sound energy at resonance; VASER-Solta Medical, Bothell, WA) liposuction in secondary abdominal liposculpture to address these challenges.

Methods

A prospective cohort study was conducted between May 2022 and May 2023 of patients undergoing secondary abdominal liposculpture with US-assisted VASER liposuction, at least 12 months after their initial procedure. Preoperative US examinations were performed to identify and mark findings related to previous liposuction. Data on demographics, photographic results, and complications were collected and analyzed.

Results

Intraoperative ultrasound (I-US) significantly improved the detection of fibrotic lesions, leading to more precise, rapid, and atraumatic outcomes. The use of I-US optimized surgical procedures, reducing both costs and operation time. Clear communication with patients regarding potential limitations due to chronic damage was essential for setting realistic expectations.

Conclusions

I-US has proven to be an invaluable tool in secondary liposculpture, enhancing surgical precision and outcomes. This methodology allows for better recognition of complications, promoting effective treatment strategies and ultimately improving patient satisfaction in the context of secondary abdominal liposculpture.

Level of Evidence: 4 (Therapeutic)
Hybrid grain production in wheat benefits from synchronized flowering and high female flower receptivity
Authors: Schmidt Constanze , Hinterberger Valentin , Philipp Norman , Reif Jochen C , Schnurbusch Thorsten
Published: October 2024

The performance of plant hybrids relative to line breeding types is generally associated with higher yields, better adaptation, and improved yield stability. In bread wheat (Triticum aestivum L.), however, a broad commercial success for hybrids has not been accomplished until now largely due to the low efficiency of hybrid grain production, which is highly attributable to its self-pollinating nature. To better understand how hybrid wheat grains can be produced more effectively, we investigated the influence of synchronized flowering between female (i.e. male-sterile) lines and their male cross-pollinator lines as well as of the duration of flowering on hybrid grain production. We found that synchronization of flowering in combination with the longest possible temporal overlap had the largest positive effect on hybrid grain production. However, despite sufficient spatial and temporal synchronization of flowering, we also found that some female lines had lower hybrid grain set than others, suggesting genetic differences in female floral receptivity. To better assess female receptivity, we established a new phenotyping scale of male-sterile wheat flowers that provides the floral basics for effective cross-pollination. Applying this scale in our field and greenhouse trials revealed that better performing female lines remained longer in the pollen-receptive phase.
Symmetry, Invariance, and Imprecise Probability
Authors: Goodsell Zachary , Nebel Jacob M
Published: October 2024

It is tempting to think that a process of choosing a point at random from the surface of a sphere can be probabilistically symmetric, in the sense that any two regions of the sphere which differ by a rotation are equally likely to include the chosen point. Isaacs, Hájek and Hawthorne (2022) argue from such symmetry principles and the mathematical paradoxes of measure to the existence of imprecise chances and the rationality of imprecise credences. Williamson (2007) has argued from a related symmetry principle to the failure of probabilistic regularity. We contend that these arguments fail, because they rely on auxiliary assumptions about probability which are inconsistent with symmetry to begin with. We argue, moreover, that symmetry should be rejected in light of this inconsistency, and because it has implausible decision-theoretic implications. The weaker principle of probabilistic invariance says that the probabilistic comparison of any two regions is unchanged by rotations of the sphere. This principle supports a more compelling argument for imprecise probability. We show, however, that invariance is incompatible with mundane judgements about what is probable. Ultimately, we find reason to be suspicious of the application of principles like symmetry and invariance to non-measurable regions.
Localization and discrimination of GG mismatch in duplex DNA by synthetic ligand-enhanced protein nanopore analysis
Authors: Lyu Wenping , Zhu Jianji , Huang XiaoQin , Chinappi Mauro , Garoli Denis , Gui Cenglin , Yang Tao , Wang Jiahai
Published: October 2024

Mismatched base pairs in DNA are the basis of single-nucleotide polymorphism, one of the major issues in genetic diseases. However, the changes of physical and chemical properties of DNA caused by single-site mismatches are often influenced by the sequence and the structural flexibility of the whole duplex, resulting in a challenge of direct detection of the types and location of mismatches sensitively. In this work, we proposed a synthetic ligand-enhanced protein nanopore analysis of GG mismatch on DNA fragment, inspired by in silico investigation of the specific binding of naphthyridine dimer (ND) on GG mismatch. We demonstrated that both the importing and unzipping processes of the ligand-bound DNA duplex can be efficiently slowed down in α-hemolysin nanopore. This ligand-binding induced slow-down effect of DNA in nanopore is also sensitive to the relative location of the mismatch on DNA duplex. Especially, the GG mismatch close to the end of a DNA fragment, which is hard to be detected by either routine nanopore analysis or tedious nanopore sequencing, can be well differentiated by our ND-enhanced nanopore experiment. These findings provide a promising strategy to localize and discriminate base mismatches in duplex form directly at the single-molecule level.
Molecular basis for the transcriptional regulation of an epoxide-based virulence circuit in Pseudomonas aeruginosa
Authors: He Susu , Taher Noor M , Simard Adam R , Hvorecny Kelli L , Ragusa Michael J , Bahl Christopher D , Hickman Alison B , Dyda Fred , Madden Dean R
Published: October 2024

The opportunistic pathogen Pseudomonas aeruginosa infects the airways of people with cystic fibrosis (CF) and produces a virulence factor Cif that is associated with worse outcomes. Cif is an epoxide hydrolase that reduces cell-surface abundance of the cystic fibrosis transmembrane conductance regulator (CFTR) and sabotages pro-resolving signals. Its expression is regulated by a divergently transcribed TetR family transcriptional repressor. CifR represents the first reported epoxide-sensing bacterial transcriptional regulator, but neither its interaction with cognate operator sequences nor the mechanism of activation has been investigated. Using biochemical and structural approaches, we uncovered the molecular mechanisms controlling this complex virulence operon. We present here the first molecular structures of CifR alone and in complex with operator DNA, resolved in a single crystal lattice. Significant conformational changes between these two structures suggest how CifR regulates the expression of the virulence gene cif. Interactions between the N-terminal extension of CifR with the DNA minor groove of the operator play a significant role in the operator recognition of CifR. We also determined that cysteine residue Cys107 is critical for epoxide sensing and DNA release. These results offer new insights into the stereochemical regulation of an epoxide-based virulence circuit in a critically important clinical pathogen.
SYNBIP 2.0: epitopes mapping, sequence expansion and scaffolds discovery for synthetic binding protein innovation
Authors: Li Yanlin , Li Fengcheng , Duan Zixin , Liu Ruihan , Jiao Wantong , Wu Haibo , Zhu Feng , Xue Weiwei
Published: October 2024

Synthetic binding proteins (SBPs) represent a pivotal class of artificially engineered proteins, meticulously crafted to exhibit targeted binding properties and specific functions. Here, the SYNBIP database, a comprehensive resource for SBPs, has been significantly updated. These enhancements include (i) featuring 3D structures of 899 SBP–target complexes to illustrate the binding epitopes of SBPs, (ii) using the structures of SBPs in the monomer or complex forms with target proteins, their sequence space has been expanded five times to 12 025 by integrating a structure-based protein generation framework and a protein property prediction tool, (iii) offering detailed information on 78 473 newly identified SBP-like scaffolds from the RCSB Protein Data Bank, and an additional 16 401 555 ones from the AlphaFold Protein Structure Database, and (iv) the database is regularly updated, incorporating 153 new SBPs. Furthermore, the structural models of all SBPs have been enhanced through the application of the AlphaFold2, with their clinical statuses concurrently refreshed. Additionally, the design methods employed for each SBP are now prominently featured in the database. In sum, SYNBIP 2.0 is designed to provide researchers with essential SBP data, facilitating their innovation in research, diagnosis and therapy. SYNBIP 2.0 is now freely accessible at https://idrblab.org/synbip/.
The pathogen-induced peptide CEP14 is perceived by the receptor-like kinase CEPR2 to promote systemic disease resistance in Arabidopsis
Authors: Wang Xiaoyang , Yu Wenlong , Yuan Qin , Chen Xinyu , He Yunxia , Zhou Jinggeng , Xun Qingqing , Wang Guodong , Li Jia , Meng Xiangzong
Published: October 2024

Secreted plant peptides that trigger cellular signaling are crucial for plant growth, development, and adaptive responses to environmental stresses. In Arabidopsis (Arabidopsis thaliana), the C-TERMINALLY ENCODED PEPTIDE (CEP) family is a class of secreted signaling peptides that is phylogenetically divided into 2 groups: group I (CEP1–CEP12) and group II (CEP13–CEP15). Several group I CEP peptides regulate root architecture and nitrogen starvation responses, whereas the biological activity and roles of group II CEPs remain unknown. Here, we report that a group II CEP peptide, CEP14, functions as a pathogen-induced elicitor of Arabidopsis immunity. In response to infection by the bacterial pathogen Pseudomonas syringae, CEP14 expression was highly induced via the salicylic acid pathway in Arabidopsis leaves and roots. In the absence of a pathogen attack, treatment of Arabidopsis plants with synthetic CEP14 peptides was sufficient to trigger immune responses. Genetic and biochemical analyses demonstrated that the receptor-like kinase CEP RECEPTOR 2 (CEPR2) perceives CEP14 to trigger plant immunity. The SOMATIC EMBRYOGENESIS RECEPTOR KINASES (SERKs) BRASSINOSTEROID INSENSITIVE 1-ASSOCIATED RECEPTOR KINASE 1 (BAK1) and SERK4 also participated in CEP14 perception by forming CEP14-induced complexes with CEPR2. Overexpression of CEP14 largely enhanced Arabidopsis resistance to P. syringae, while CEP14 or CEPR2 mutation significantly attenuated Arabidopsis systemic resistance to P. syringae. Taken together, our data reveal that the pathogen-induced CEP14 peptide, which is perceived by the CEPR2-BAK1/SERK4 receptor complexes, acts as an endogenous elicitor to promote systemic disease resistance in Arabidopsis.
Unpacking the discourse surrounding the impact agenda in the Hong Kong Research Assessment Exercise 2020
Authors: Li Danling , Lo William Yat Wai , Yang Rui
Published: October 2024

Research with economic utility and social value has been increasingly valued. Such an emphasis can be evidenced by the newly included assessment element of ‘societal impact’ in performance-based research funding (PBRF) schemes in different higher education systems around the world. This paper investigates how the non-academic impact is constructed and perceived in the Hong Kong Research Assessment Exercise (RAE) 2020, taking into account the local socio-cultural characteristics in the context of Hong Kong. Data sources include 13 impact case studies in the education panel submitted for the Hong Kong RAE 2020 and semi-structured interview with 17 education academics in Hong Kong. Findings revealed that the non-academic impact was constructed through a narrative pattern: (1) problem identification: tensions and synergies between local and international discourse; (2) problem resolution: prioritization of the evidence-based applied education research (with funding); (3) resolution dissemination: strategic employment of promotional genre. The paper discusses how decolonization, academic entrepreneurialism and collectivist culture have characterized the framing and understanding of the non-academic impact in the Hong Kong academia, contributing to the discourse on neoliberalism in higher education by providing a nuanced, local perspective on the impact agenda. Policy implications for a more localized and flexible impact agenda are also provided.
Trajectories of disease evolution upon treatment initiation in systemic lupus erythematosus: results from four clinical trials of belimumab
Authors: Parodis Ioannis , Lindblom Julius , Tsoi Alexander , Palazzo Leonardo , Blomkvist Sporre Karin , Enman Yvonne , Nikolopoulos Dionysis , Beretta Lorenzo
Published: October 2024

Objective

Upon commencement of therapy for active disease, patients with systemic lupus erythematosus (SLE) show varying evolution regarding disease activity measures and patient-reported outcomes (PROs). Our objective was to identify disease evolution trajectories to gain a deeper understanding of SLE progression, ultimately improving future trial design.

Methods

Patients with ≥2 visits and available data on Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K), British Isles Lupus Assessment Group (BILAG), Physician Global Assessment (PGA), Functional Assessment of Chronic Illness Therapy—Fatigue (FACIT-F), and glucocorticoid use were included in a post hoc analysis of four randomized controlled trials of belimumab (BLISS-52, BLISS-76, BLISS-SC, EMBRACE). Growth mixture modelling identified latent classes.

Results

Among 2868 patients analysed, baseline median disease duration was 4.5 (interquartile range: 1.5–9.7) years and mean (±standard deviation) Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) Damage Index (SDI) 0.7 (±2.0), SLEDAI-2K 10.2 (±3.6), BILAG 17.0 (±7.8), PGA 1.5 (±0.5), FACIT-F 30.6 (±11.9) and prednisone dose 11.0 (±8.9) mg/day. In the initial model, glucocorticoid use and dose yielded high standard errors, indicating a weak link with the latent process. A refined model considered only clinical measures and FACIT-F, corrected for intervention and SDI; no other covariates improved the fit. Four classes best described disease evolution: highly active, responders; highly active, non-responders; moderately active, responders; moderately active, non-responders. Lupus Low Disease Activity State and Definitions of Remission in SLE remission attainment associated with latent classes.

Conclusion

By linking disease activity measures with PROs, we identified four distinct trajectories describing SLE evolution following the initiation of therapy. This classification could be valuable for personalizing treatment and guiding biological studies aimed at distinguishing patients with varying anticipated treatment responses, as no single clinical variable alone can predict disease progression.
30-Month Impact of Medications for Opioid Use Disorder on Acute Care Utilization in Rural Communities
Authors: Maeng Daniel , Russell Holly A. , Conner Kenneth R. , Malcho Jade , Cross Wendi , Lee Hochang B.
Published: October 2024

Purpose

To assess both the short- and longer-term impact of offering medications for opioid use disorder (MOUD, ie, methadone, buprenorphine, or naltrexone) on rates of all-cause emergency department (ED) visits and acute inpatient admissions (IP) over a 30-month period among Medicaid enrollees with opioid use disorder (OUD) residing in rural communities.

Methods

A quasi-experimental retrospective analysis of longitudinal Medicaid claims data among continuously enrolled adult patients with OUD residing in 71 predominantly rural counties in the United States between 2018 and 2020. A cohort of patients receiving MOUD treatment was compared against a contemporaneous propensity score–matched comparison group consisting of those who received no MOUD during the period.

Findings

The sample included 5370 patients with OUD in each group. At the index period (ie, the month in which any MOUD was used for the first time), buprenorphine was the most commonly used MOUD (82% of the MOUD treatment group). By the eighth month since the index period, MOUD use dropped below 60% among the MOUD treatment group. Over the 30-month post-MOUD period, MOUD treatment was associated with 24% (112 vs 148 per 1000 per month) and 52% (21 vs 44) lower rates of ED visit and IP admission rates, respectively (P < 0.001), relative to the comparison group. Moreover, the reductions persisted well after the 18th month period.

Conclusions

Receipt of MOUD was associated with both immediate- and long-term lower rates in acute care utilization rates among adult Medicaid beneficiaries with OUD residing in rural communities despite significant treatment discontinuation.
Persistent Fatigue, Weakness, and Aberrant Muscle Mitochondria in Survivors of Critical COVID-19
Authors: Mayer Kirby P. , Ismaeel Ahmed , Kalema Anna G. , Montgomery-Yates Ashley A. , Soper Melissa K. , Kern Philip A. , Starck Jonathan D. , Slone Stacey A. , Morris Peter E. , Dupont-Versteegden Esther E. , Kosmac Kate
Published: October 2024

OBJECTIVES:

Persistent skeletal muscle dysfunction in survivors of critical illness due to acute respiratory failure is common, but biological data elucidating underlying mechanisms are limited. The objective of this study was to elucidate the prevalence of skeletal muscle weakness and fatigue in survivors of critical illness due to COVID-19 and determine if cellular changes associate with persistent skeletal muscle dysfunction.

DESIGN:

A prospective observational study in two phases: 1) survivors of critical COVID-19 participating in physical outcome measures while attending an ICU Recovery Clinic at short-term follow-up and 2) a nested cohort of patients performed comprehensive muscle and physical function assessments with a muscle biopsy; data were compared with non-COVID controls.

SETTING:

ICU Recovery Clinic and clinical laboratory.

PATIENTS/SUBJECTS:

Survivors of critical COVID-19 and non-COVID controls.

INTERVENTIONS:

None.

MEASUREMENTS AND MAIN RESULTS:

One hundred twenty patients with a median of 56 years old (interquartile range [IQR], 42–65 yr old), 43% female, and 33% individuals of underrepresented race attended follow-up 44 ± 17 days after discharge. Patients had a median Acute Physiology and Chronic Health Evaluation-II score of 24.0 (IQR, 16–29) and 98 patients (82%) required mechanical ventilation with a median duration of 14 days (IQR, 9–21 d). At short-term follow-up significant physical dysfunction was observed with 93% of patients reporting generalized fatigue and performing mean 218 ± 151 meters on 6-minute walk test (45% ± 30% of predicted). Eleven patients from this group agreed to participate in long-term assessment and muscle biopsy occurring a mean 267 ± 98 days after discharge. Muscle tissue from COVID exhibited a greater abundance of M2-like macrophages and satellite cells and lower activity of mitochondrial complex II and complex IV compared with controls.

CONCLUSIONS:

Our findings suggest that aberrant repair and altered mitochondrial activity in skeletal muscle associates with long-term impairments in patients surviving an ICU admission for COVID-19.
Examining Mentor Perception of Competence in an Academic Peer Mentoring Program
Authors: Zwilling Elizabeth , Jeanmougin Caitlin , Cole Britt
Published: October 2024

Introduction:

Peer mentoring programs can be a valuable support mechanism for new faculty transitioning from clinical practice to academia. Mentors play a crucial role in this process. This study described mentors' perceived competence in 21 areas of the mentor role and their experiences as mentors following the first year of a structured peer mentoring program.

Methods:

This study employed a mixed-methods approach, using the Mentoring Competency Assessment-21 alongside open-ended questions. These instruments were electronically administered to a convenience sample consisting of eight mentors with varying experience ranging from 2 to 16 years in the nursing program at a mid-sized university, following an intentional first-year peer mentoring program.

Results:

The highest-performing items were “Establishing a relationship based on trust” (M 6.50, SD 0.53), “Considering how personal and professional differences may impact expectations” (M 6.25, 0.83), and “Acknowledging your mentee's professional contributions” (M 6.13, SD 0.99). The lowest scores were focused on estimating scientific knowledge and scholarly productivity. Responses to the Mentoring Competency Assessment-21 indicated that mentors felt at least moderately competent in the various aspects of the faculty mentor role. Mentors valued the professional development and supporting materials provided by the development team. An identified area for improvement was the support provided to assist the mentees' scholarly development.

Discussion:

This study underscores the importance of supportive materials, such as handbooks and regular communication, in fostering mentor competence and facilitating successful nursing faculty peer mentoring programs. Future research implications include assessment of mentor competence by mentees and long-term follow-up of program outcomes.
Achieving a Strong and Straight Septal Extension Graft: A Novel Four-step Surgical Approach in Rhinoplasty
Authors: Di Giuli Riccardo , Mafi Pouya , Belloni Laura M. , Vaccari Stefano , Klinger Francesco , Roxo Carlos W.
Published: October 2024

Background:

Septal extension grafts allow the precise elongation of the nasal septum to attain facial harmony and optimize aesthetic outcomes. In this context, septal surgery requires meticulous design to address both functional and aesthetic goals. Traditional septoplasty techniques often overlook aesthetic considerations and postoperative nasal structural stability, resulting in unresolved or recurrent deviations, nose tip drooping, and obstruction recurrences. Despite advancements in surgical techniques, achieving simultaneous septal alignment and long-term stability remains a significant challenge.

Methods:

This study introduces a systematic 4-step technique. The procedure encompasses caudal septum liberation, placement of the septum extension cartilage graft, positioning of an ethmoidal bone graft, and redefinition through an intermediate cartilage.

Results:

A retrospective analysis of outcomes involving 753 patients was conducted with a minimum follow-up of 6 months. During follow-up visits, 1.73% of cases exhibited residual columellar asymmetry, and 0.66% showed tip asymmetries. The infection rate was 0.40%, with no cases of tip drop identified. The overall satisfaction rating on the Rhinoplasty Outcomes Evaluation questionnaire at 12 months postoperative was 9.3.

Conclusions:

The technique provides a systematic approach to integrate functional and aesthetic objectives, emphasizing septal stability and alignment while concurrently addressing tip projection and stability. The study provides comprehensive insights into the principles, methodology, and advantages of this rhinoplasty technique. The outcomes underscore the efficacy of the technique, presenting a reliable and long-term stable solution.