bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultra-peripheral collisions of charged hadrons in extensive air showers
Authors: Masip Manuel , Rosario Ivan , Sciutto Sergio J.
Published: July 2023

We discuss the electromagnetic collisions of high energy protons, pions and kaons with
atmospheric nuclei. In particular, we use the equivalent photon approximation to estimate (i) the diffractive collisions where the projectile scatters inelastically off a nucleus, and
 (ii) the usual radiative processes (bremsstrahlung, pair production and photonuclear
interactions) of these charged hadrons in the air. We then include the processes in the simulator
AIRES and study how they affect the longitudinal development of extensive air showers. For
109-11 GeV proton primaries we find that they introduce a very small reduction (below 1%) in
the average value of both X
max and ΔX
max. At a given shower age (relative slant depth from
 X
max), these electromagnetic processes slightly increase the number of charged particles at the
shower maximum and reduce the number of muons when it is old, decreasing by 1% the
muon-to-(γ + e) near the ground level.
Constraints on the non-minimally coupled Witten-O'Raifeartaigh inflation
Authors: dos Santos F.B.M. , Silva R. , Alcaniz J.S.
Published: July 2023

We investigate the impact of a non-minimal coupling of the scalar field with gravity in
inflationary models, where a small coupling is allowed. As a concrete example, we consider the
Witten-O'Raifeartaigh model, where, in line with other models, the presence of a coupling strength
 ξ can recover concordance of the inflationary parameters with cosmic microwave background (CMB) constraints, provided by the Planck collaboration. We go beyond the slow-roll regime and
investigate the impact in the description of CMB anisotropies by performing a statistical analysis
of the model with the most recent Planck + Baryon Acoustic Oscillations (BAO) data to seek for any
indication of a non-zero coupling by data within the model. We find that not only the presence of
a non-minimal coupling is seen, but the model has a slight statistical preference when compared
with the standard ΛCDM one. We also discuss the results on the minimally-coupled model,
which in general, favours the simple setting where the associated mass scale is equal to the
reduced Planck mass Mp
while being, in general, disfavored concerning the standard model.
Kinetic field theory: generic effects of alternative gravity theories on non-linear cosmic density-fluctuations
Authors: Oestreicher A. , Capuano L. , Matarrese S. , Heisenberg L. , Bartelmann M.
Published: July 2023

Non-linear cosmic structures contain valuable information on the expansion history of the background space-time, the nature of dark matter, and the gravitational interaction. The recently developed kinetic field theory of cosmic structure formation (KFT) allows to accurately calculate the non-linear power spectrum of cosmic density fluctuations up to wave numbers of k ≲ 10 h Mpc-1 at redshift zero. Cosmology and gravity enter this calculation via two functions, viz. the background expansion function and possibly a time-dependent modification of the gravitational coupling strength.

The success of the cosmological standard model based on general relativity suggests that cosmological models in generalized theories of gravity should have observable effects differing only weakly from those in standard cosmology. Based on this assumption, we derive the functional, first-order Taylor expansion of the non-linear power spectrum of cosmic density fluctuations obtained from the mean-field approximation in KFT in terms of the expansion function and the gravitational coupling strength. This allows us to study non-linear power spectra expected in large classes of generalized gravity theories. To give one example, we apply our formalism to generalized Proca theories.
Characterization of a pnCCD-based Camera for Applications at the 100 m X-Ray Test Facility*
Authors: Hou Dongjie , Wang Yusa , Zhao Zijian , Zhao Xiaofan , Yang Xiongtao , Ma Jia , Zhu Yuxuan , Xu Yupeng , Chen Yong , Liu Congzhan , Huth Martin , Majewski Petra , Soltau Heike , Strüder Lothar , Lu Fangjun , Zhang Shuang-Nan , Xu He , Wu Bobing
Published: July 2023

The 100 m long X-ray test facility (100XF for clarity) in Institute of High Energy Physics of CAS has been playing an increasingly important role in the X-ray astronomy field in China. 100XF has been contributing to the missions under development, such as the Einstein Probe mission. The facility has also been providing support to R&D of focusing X-ray optics in China that will enable future X-ray telescopes to be realized, such as the enhanced X-ray Timing and Polarization (eXTP) mission. A pnCCD-based camera has been employed at 100XF to rapidly measure the performance of the X-ray optics. In this work, we study the performance of the camera and its spectral and imaging applications at 100XF. The camera system can provide a high frame readout rate, with a low readout noise <3 e−. It is sensitive to X-ray photons in the 3–10 keV energy band with a high quantum efficiency exceeding 90%. Actually, the low threshold of detection energy range can reach down to 0.2 keV. The energy resolution can reach 145.2 eV for single events and 154.8 eV for all valid events (including single events and split events) at 6.4 keV. The camera also exhibits excellent imaging capability in both the full frame mode and the windowing mode, with a readout rate of up to 1000 Hz. Finally, a prototype of a focusing X-ray mirror shell of eXTP was smoothly measured with this camera. The obtained on-axis point-spread function and half-power diameter are consistent with expectations. It is proven that the camera can improve the capability of 100XF in characterizing the X-ray optics. This camera will be very useful for performing on-ground calibrations for future X-ray telescope missions.
Phase transition in bilayer quantum Hall system with opposite magnetic field
Authors: Yang 杨 Ke 珂
Published: July 2023

We construct a mapped bilayer quantum Hall system to realize the proposal that two nearly flatbands have opposite Chern numbers. For the C = ±1 case, the two Landau levels of the bilayer experience opposite magnetic fields. We consider a mapped bilayer quantum Hall system at total filling

ν
t

=

1
2

+

1
2

where the intralayer interaction is repulsive and the interlayer interaction is attractive. We take exact diagonalization (ED) calculations on a torus to study the phase transition when the separation distance d/lB
is driven. The critical point at d
c/lB
= 0.68 is characterized by a collapse of degeneracy and a crossing of energy levels. In the region d/lB
< d
c/lB
, the states of each level are highly degenerate. The pair-correlation function indicates electrons with opposite pseudo-spins are strong correlated at
r
= 0. We find an exciton stripe phase composed of bound pairs. The ferromagnetic ground state is destroyed by the strong effective attractive potential. An electron composite-Fermion (eCF) and a hole composite Fermion (hCF) are tightly bound. In the region d/lB
> d
c/lB
, a crossover from the d → d
c limit to the large d limit is observed. The electron and hole composite Fermion liquids (CFL) are realized by composite Fermions (CF) which attach opposite fluxes, respectively.
Structural design and mechanical performance verification of a mobile piler with a double-scissor fork
Authors: Chen Zhuoyuan , Wang Shaocan , Li Peiyang , Liu Xiaoyong , Qin Aizhong , Liu Xiang
Published: July 2023

The traditional piler structure is column type. The stacker of this structure needs the same height as the top of the warehouse. At present, there is no good solution for highly inconsistent special-shaped warehouses. This paper proposes a piler based on the requirement of variable height of the piler based on a double shear fork mechanism. The double shear difference mechanism drives the lifting and lowering of the piler. Since there is no need to arrange rails on the top of the warehouse, they can be used in warehouses with different heights. Especially for warehouses with a height of less than 3 m, this new structure of piler has broad application space and application prospects. Finally, according to the actual working force of the piler, the mechanical model is established and verified by FEM. It is proved that the stacking machine with this structure has good mechanical properties.
Optimization of cutting parameters based on surface partitioning
Authors: Chen Liangji , Li Zhiguang , Li Huiying
Published: July 2023

With the rapid development of science and technology, five-axis CNC machine tools are widely used in the field of complex surface parts processing and manufacturing, so the part geometry model of the complex surface becomes more and more complex. Most traditional machining methods use fixed cutting parameters to calculate and generate five-axis machining toolpaths. If the fixed cutting parameters are used to generate the 5-axis machining toolpaths, the optimal cutting condition will not be obtained in some parts, and the generated machining toolpaths will be less adaptable. In this paper, the complex surface is partitioned and the cutting parameters are optimally adjusted to different parts of the workpiece during the cutting process to respond to the change in the cutting state.
A Non-thermal De-icing Technique Using Ultrasonic Guided Waves
Authors: Xu Peiyi , Zhang Donglai , Gao Wei , Li Anshou
Published: July 2023

A non-thermal and low-cost ultrasonic de-icing method was applied in this study to solve the problem of ice accumulation on the surface of the structure. Numerical simulation analysis and an experimental test were conducted to confirm the feasibility of non-thermal de-icing. The shear stresses generated by a transducer at different installation locations were calculated in ANASYS simulation software to determine the optimal installation location and excitation frequency of the transducer. The de-icing experiment shows that the ice patch (60mm × 60mm × 4mm) was removed in less than ten seconds notwithstanding in a freezer at - 25 °C. The thermocouple temperature curve shows that the surface temperature of the plate is always below 0 °C. In other words, the icing is removed by force rather than thermal effects. The results of the ANSYS numerical simulation are consistent with those of the experiment, which indicates that the ANSYS numerical simulation provides a good reference for the de-icing experiment. Both the numerical simulation and the experiment confirm that non-thermal de-icing can be realized using a sandwich ultrasonic transducer.
Grinding Path Planning of Abrasive Cloth Wheel Based on Modified Preston Equation
Authors: Gao Zhenchao , Zheng Gang
Published: July 2023

As for the efficient and high-precision grinding of blades, it was studied that a flexible grinding path planning method of the abrasive cloth wheel of the blades. In the paper, based on modified Preston equation, the radial material removal depth model is supplemented, which provides theoretical support for the establishment of the flexible grinding path of the abrasive cloth wheel. After obtaining the abrasive cloth wheel envelope surface by the double parameter sphere family method, the deformation amount of the abrasive cloth wheel is used as the directed distance from the point of the designed surface to the envelope. The sequential linear optimization algorithm is used to optimize the directed distance. Then, the flexible grinding path for constant material removal is obtained. The results of the simulation show that the profile error of the blade processing is improved under the requirements of surface roughness.
Fault Diagnosis Method for Rotating Machinery Based on Improved CBR
Authors: Xie Xuyang , Yang Zichun , Zhang Lei , Wang Jintao , Zeng Guoqing , Wang Xuefeng , Chen Guobing
Published: July 2023

A novel method to detect the faults of rotating machinery using improved case-based reasoning is proposed in this article, which can fully utilize the experience and intelligence of previous cases to realize an intelligent diagnosis. Especially, the identification process of a new fault state is designed to address the problem that the state not included in the case base cannot be automatically recognized. The presented approach is performed to test the gear and bearing datasets. And good diagnosis results are achieved, which verifies the effectiveness of the presented approach.
Design of Aeroengine Air Leak Automatic Monitoring System Based on Infrared Thermography
Authors: Ma Anxiang , Qian Rongrong , Li Yanhong , Xie Qifei , Dong Shaoxuan
Published: July 2023

The aeroengine often suffers from air leaks during the test, which will affect the performance of the aeroengine, thus affecting the test task and even the test safety. In order to make up for the low efficiency and poor real-time of traditional manual detection methods for aeroengine air leaks, a design scheme for aeroengine leakage real-time automatic detection system is proposed. The system uses infrared thermography technology to collect real-time infrared information on the surface of the aeroengine during the test and then generates thermal images. The image processing technology is used to identify the leakage fault and locate the leakage location. Through the design and analysis of the system architecture, composition unit, operation principle and key technologies of the system implementation, the designed air leak monitoring system has high feasibility. Compared with traditional air leak detection methods, the system has the advantages of real-time, automaticity, remoteness, non-contact, non-destructive, simplicity, and intuitiveness, and can significantly improve the efficiency of aeroengine air leak fault detection.
A fault diagnosis method on GWO-SPA and MAE for fault diagnosis of reciprocating compressors
Authors: Li Ying , Wu Shihu , Chen Jiawen , Ba Peng
Published: July 2023

Given the non-stationary and nonlinear features of the reciprocating compressor vibration signal, as well as the problems of end-point effect and modal aliasing existing in the current adaptive decomposition method, the fault diagnosis method for reciprocating compressors based on gray wolf optimization-smoothness priors approach (GWO-SPA) and multiscale attention entropy (MAE) is proposed in this paper. The selection of the regularization parameter λ in the SPA algorithm is studied, and the GWO is introduced to improve the decomposition effect of the SPA method. Then, the entropy value of the MAE is calculated for the detrended term components decomposed by GWO-SPA to describe the fault characteristics quantitatively, and perform PCA dimensionality reduction processing. Finally, the optimized feature vector is input into the SVM. Through the experiments show it is proved that the method proposed can effectively extract the fault state features of reciprocating compressors, and realize the accurate distinction of the fault types of reciprocating compressors.
Cause Analysis and Theoretical Study of Bolt Self-loosening Under a High-temperature Condition
Authors: Li Wenbo , Ding Baoping , Cheng Peng , Li Qing
Published: July 2023

With the wide application of bolt connection, the application environment of the bolt is more and more complicated. The problem of bolt loosening caused by high temperatures cannot be ignored. Based on the research status of domestic and foreign experts, this paper analyzes the causes of high-temperature bolt loosening and introduces theoretical research on this problem. The conclusion is drawn that the factors affecting bolt loosening under high-temperature conditions and the anti-loosening measures are put forward.
Research on Vibration Control of Paired Inclined Nozzles Dynamic Coupled Tubes
Authors: Yang Liang , Qiu Ming , Liao Zhenqiang , Song Jie , Li Zijian , Huang Wenjun
Published: July 2023

The barrel vibrates violently, which will lead to a serious drop in shooting accuracy. To solve this issue, a barrel vibration control method of the paired oblique nozzle dynamic couple is proposed. A pair of inclined nozzle devices are designed on the barrel to fully use the gunpowder gas energy in the chamber during the shooting process. A dynamic couple is generated to balance the turning moment of the barrel weapon. Simultaneously, the recoil force is reduced by exporting the gunpowder gas in the chamber. Therefore, the vibration of the barrel is reduced. Firstly, the internal ballistic two-phase flow model including the gas transient flow model in the vibration control device is modelled based on the internal ballistic theory of two-phase flow. Secondly, the numerical simulation of the weapon launching process is carried out. Thirdly, the rigid-flexible coupling firing dynamics modelling and simulation research is conducted on a 30mm chain gun equipped with a paired oblique nozzle dynamic couple vibration control device. At last, the effects of the device on the continuous firing vibration control of barrel weapons are analyzed. The results show that the vibration reduction efficiency of the inclined nozzle is better than that of the vertical nozzle and the horizontal nozzle. When the angle of the inclined nozzle is 30°, the barrel shows the highest vibration reduction efficiency. The vibration reduction efficiency of each vibration characteristic is 39.2%, 17.1%, 44.8%, and 48.9%, respectively.
Design of Indirect Tire Pressure Monitoring System Based on Wheel Speed Signal
Authors: Huo Bingyuan , Zhang Mengdong , Zhong Shaohua , Zhou Fuzhi
Published: July 2023

Keeping the pressure of the automobile tire in the normal working range is an important guarantee for the safety of the automobile. When the tire leaks, the driver should be reminded to check or replace the tire before the potential danger of blowing out. Aiming at the safety problem of commercial vehicle driving, a set of tire pressure monitoring alarm systems is designed by combining the radius method and frequency method. The magneto-electric wheel speed sensor is used to collect and process the tire speed, and then through the data processing, the full range of monitoring each tire’s possible air leakage hazards, such as emergency can be quickly warned, thus providing a reference for the driver’s driving. The experimental results show that the system can effectively improve the accuracy and stability of tire pressure monitoring.
A Relaxed MPC Method for Non-rigid Shell to Solid Coupling
Authors: Lu Daxing , Zhang Meng , Yang Zhaotong
Published: July 2023

In the finite element model of the water tank without reinforced ribs, most of the water tank structure is constructed with thin-walled parts, which are usually represented by the shell element, and for the local area with a large thickness structure, the usually solid element is used. For this area, the shell element cannot accurately simulate the stress concentration effect, while simulation with the full solid element is very time-consuming because of a large number of FE meshes. The Focus of this paper is to improve computation efficiency while ensuring the accuracy of the calculation. In this paper, a novel MPC method with a relaxed factor is proposed. Compared with the classical shell-to-solid method, the calculation results of the MPC method with relaxation factor are closer to the reference model, while the calculation time is significantly reduced by 42.1 %.
Research on Trajectory Planning and Simulation of Six-Degree-of-Freedom Manipulator
Authors: Jiang Qiang , Zhang Yulian
Published: July 2023

To make the time of the mechanical arm in joint space movement as short as possible and improve work efficiency, it is momentous to plan the movement trajectory of the mechanical arm to content the necessary condition of a smooth movement curve of the mechanical arm. According to the working principle of the 6-DOF mechanical arm, the D-H modeling method is used to calculate the D-H arguments, and the six-degree-of-freedom mechanical arm D-H model is established using MATLAB’s Robotics toolbox, and the positive kinematics analysis is performed. According to the set up robot arm model, the trajectory designning of the mechanical arm to run by using the three-time polynomial interpolation technique and the five-time polynomial interpolation technique in the joint space comparison, and it is simulated in MATLAB. Simulation experiments show that the five-time polynomial interpolation technique makes the running curve of the mechanical arm smoother and more stable, and has more application value.
What surfaces in the operation of noble liquids dark matter detectors
Authors: Pereverzev S.
Published: July 2023

Though noble element dual-phase detectors have a long application history in dark matter searches, some uncertainties and differences in backgrounds persist. We compare effects caused by unextracted electrons on the liquid-gas interface in Xe and Ar dual-phase detectors with a large family of phenomena at the liquid helium surface. We pose that electron and ion accumulation on the liquid surface in detectors can lead to the formation of ordered surface states, charged liquid surface instabilities in an electric field, electrospraying, interactions with surface waves, and other effects. Not only delayed electron emission signals can be generated, but the extraction efficiency for electrons produced below the liquid surface can be altered by the presence of surface charges. Several factors lead to surface electron accumulation, and problems can become more severe with the increased detector size. We discuss possible experiments to reveal surface electron effects and design changes to alleviate electron accumulation. We conclude that studies of these effects are desirable before making final design decisions for the new multi-ton liquid Xe dark matter detector projects like DARWIN, XLZD, and large Ar dual-phase detectors.
Suitability Assessment of CsPbI_3 Dosimeter with ^192Ir Source for Brachytherapy Quality Assurance
Authors: Yang S.W. , Park S.K. , Moon C.W. , Kim K.H.
Published: July 2023

In brachytherapy, quality assurance (QA) is a prerequisite
to minimize the dose irradiation to the healthy tissues in patients
during treatment, as it evaluates the accuracy of the dose applied
to the patients as well as the accuracy of the position of the
irradiation. Therefore, a strong emphasis has been placed on
brachytherapy QA in clinical practice. This study assessed the
suitability of a CsPbI3 dosimeter for the brachytherapy QA
system. To verify the reliability of the unit cell sensor fabricated
with CsPbI3, the electrical parameters were evaluated, after
which the position dependence of the sensor was analyzed. A high
level of reliability (R
2 > 0.99) and reproducibility (relative
standard deviation < 1.5%) were observed. The maximal value
measured at the isocenter of the sensor as the distance of the
dosimeter from the irradiation source was gradually decreased. When
the optimal angle was assessed, the variation was as high as
5.01 nC depending on the form of the 192Ir source. Therefore,
the CsPbI3 dosimeter fabricated in this study is a suitable
substitute for the conventional QA dosimeter.
Effect of spin on the instability of THz plasma waves in field-effect transistors under non-ideal boundary conditions
Authors: ZHANG 张 Liping 丽萍 , LI 李 Jiani 佳妮 , FENG 冯 Jiangxu 江旭 , SU 苏 Junyan 俊燕
Published: July 2023

Terahertz (THz) radiation can be generated due to the instability of THz plasma waves in field-effect transistors (FETs). In this work, we discuss the instability of THz plasma waves in the channel of FETs with spin and quantum effects under non-ideal boundary conditions. We obtain a linear dispersion relation by using the hydrodynamic equation, Maxwell equation and spin equation. The influence of source capacitance, drain capacitance, spin effects, quantum effects and channel width on the instability of THz plasma waves under the non-ideal boundary conditions is investigated in great detail. The results of numerical simulation show that the THz plasma wave is unstable when the drain capacitance is smaller than the source capacitance; the oscillation frequency with asymmetric boundary conditions is smaller than that under non-ideal boundary conditions; the instability gain of THz plasma waves becomes lower under non-ideal boundary conditions. This finding provides a new idea for finding efficient THz radiation sources and opens up a new mechanism for the development of THz technology.
Do Adverse Childhood Experiences Modify the Association Between Disaster-Related Trauma and Cognitive Disability?
Authors: Okuzono Sakurako S , Slopen Natalie , Shiba Koichiro , Yazawa Aki , Kondo Katsunori , Kawachi Ichiro
Published: July 2023

Identifying subpopulations that are particularly vulnerable to long-term adverse health consequences of disaster-related trauma is needed. We examined whether adverse childhood experiences (ACEs) potentiate the association between disaster-related trauma and subsequent cognitive disability among older adult disaster survivors. Data were from a prospective cohort study of older adults who survived the 2011 Great East Japan Earthquake. The baseline survey pre-dated the disaster by 7 months. We included participants who completed follow-up surveys (2013 and 2016) and did not have a cognitive disability before the disaster (n = 602). Disaster-related traumas (i.e., home loss, loss of friends or pets) and ACEs were retrospectively assessed in 2013. Cognitive disability levels in 2016 were objectively assessed. After adjusting for pre-disaster characteristics using a machine learning–based estimation approach, home loss (0.19, 95% confidence interval (CI): 0.09, 0.28) was, on average, associated with greater cognitive disability. Among individuals with ACEs, home loss was associated with even higher cognitive disability levels (0.64, 95% CI: 0.24, 1.03). Losses of friends (0.18, 95% CI: 0.05, 0.32) and pets (0.13, 95% CI: 0.02, 0.25) were associated with higher cognitive disability levels only among those with ACEs. Our findings suggest that individuals with a history of ACEs may be particularly vulnerable to adverse health consequences related to disasters.
Trends in Aesthetic Surgery Fellowship Training: An Analysis of Supply and Demand
Authors: James Isaac , Kochuba Andrew , Grow Jacob N , Ho Isabel , Calobrace M Bradley , Movassaghi Kiya , Zins James E
Published: July 2023

Background

Aesthetic surgery fellowship applications were consolidated under the San Francisco Match in 2018. The impact of these changes on aesthetic program and applicant numbers had not yet been investigated.

Objectives

In this study we sought to evaluate changes in programs, positions, applications, match rates, and fill rates since aesthetic surgery joined the San Francisco Match. We also aimed to compare these trends to craniofacial surgery, microsurgery, and hand surgery fellowships over this same time period.

Methods

San Francisco and National Resident Matching Program (NRMP) match data for aesthetic, craniofacial, microsurgery, and hand fellowships were obtained from 2018 to 2022, and the number of applications, positions, programs, and successful matches were evaluated.

Results

The number of aesthetic fellowship positions increased from 17 to 41 (141%) over the period studied. This resulted in increased match rates and more unfilled positions. Over the same period, fellowship positions for craniofacial, hand, and microsurgery increased by 3.4%, 6%, and 2.5% respectively. There was no increase in applications to any postgraduate subspecialty, nor was there any change in the number of residents pursuing fellowship. Similarly, there was no change in the percentage of fellowship-bound residents applying to any given discipline.

Conclusions

The increase in aesthetic fellowship programs and positions did not generate an increase in applications. Applications to other plastic surgery subspecialties also failed to increase. Unlike aesthetic fellowships, their program numbers have remained stable. Given the limited fellowship applicant pool, our focus should be on enhancing the quality of existing aesthetic programs rather than continuing to increase the number of aesthetic positions.

Level of Evidence: 3
The Skin Necrosis Conundrum: Examining Long-term Outcomes and Risk Factors in Implant-Based Breast Reconstruction
Authors: Hassan Abbas M , Elias Alexandra M , Nguyen Huan T , Nelson Jonas A , Mehrara Babak J , Butler Charles E , Selber Jesse C
Published: July 2023

Background

Mastectomy skin flap necrosis (MSFN) is a common complication following mastectomy that causes significant distress to patients and physicians and also compromises oncologic, surgical, and quality-of-life outcomes.

Objectives

We sought to investigate the long-term outcomes of MSFN following implant-based reconstruction (IBR) and determine the rates and predictors of post-MSFN complications.

Methods

This was a 20-year analysis of consecutive adult (>18 years) patients who developed MSFN following mastectomy and IBR from January 2001 to January 2021. Multivariable analyses were performed to identify factors associated with post-MSFN complications.

Results

We identified 148 reconstructions, with a mean follow-up time of 86.6 ± 52.9 months. The mean time from reconstruction to MSFN was 13.3 ± 10.4 days, and most cases (n = 84, 56.8%) were full-thickness injuries. Most cases (63.5%) were severe, 14.9% were moderate, and 21.6% were mild. Forty-six percent (n = 68) developed a breast-related complication, with infection being the most common (24%). An independent predictor of overall complications was longer time from reconstruction to MSFN (odds ratio [OR], 1.66; P = .040). Aging was an independent predictor of overall complications (OR, 1.86; P = .038); infection (OR, 1.72; P = .005); and dehiscence (OR, 6.18; P = .037). Independent predictors of dehiscence were longer interval from reconstruction to MSFN (OR, 3.23; P = .018) and larger expander/implant size (OR, 1.49; P = .024). Independent predictors of explantation were larger expander/implant size (OR, 1.20; P = .006) and nipple-sparing mastectomy (OR, 5.61; P = .005).

Conclusions

MSFN is associated with high risk of complications following IBR. Awareness of the timing and severity of MSFN and the predictors of post-MSFN complications is crucial for guiding evidence-based decision-making and improving outcomes.

Level of Evidence: 4
How do resource distribution and taxonomy affect the use of dual foraging in seabirds? A review
Authors: Phillips Jessica A , Guilford Tim , Fayet Annette L
Published: July 2023

In many seabird species, parents feeding young switch between short and long foraging excursions in a strategy known as “dual foraging.” To investigate whether habitat quality near breeding colonies drives the use of dual foraging, we conducted a review of the seabird literature, compiling the results of 102 studies which identified dual-foraging in 50 species across nine families from all six seabird orders. We estimated the mean distance from the colony of each species’ short and long foraging trips and obtained remote-sensed data on chlorophyll-a concentrations within the radius of both short and long trips around each colony. We then assessed, for each seabird family, the relationship between the use of dual foraging strategies and the difference in the quality of foraging locations between short- and long-distance foraging trips. We found that the probability of dual foraging grew with increasing differences in the quality of foraging locations available during short- and long-distance trips. We also found that when controlling for differences in habitat quality, albatrosses and penguins were less likely to use dual foraging than Procellariidae, which in turn were less likely to use dual foraging than Sulids. This study helps clarify how environmental conditions and taxon-specific characteristics influence seabird foraging behavior.
TraceTrack, an open-source software for batch processing, alignment and visualization of sanger sequencing chromatograms
Authors: Brazdilova Kveta , Prihoda David , Ton Quynh , Klock Heath , Bitton Danny A
Published: July 2023

Motivation

Despite the advent of next-generation sequencing technology and its widespread applications, Sanger sequencing remains instrumental for molecular biology subcloning work in biological and medical research and indispensable for drug discovery campaigns. Although Sanger sequencing technology has been long established, existing software for processing and visualization of trace file chromatograms is limited in terms of functionality, scalability and availability for commercial use.

Results

To fill this gap, we developed TraceTrack, an open-source web application tool for batch alignment, analysis and visualization of Sanger trace files. TraceTrack offers high-throughput matching of trace files to reference sequences, rapid identification of mutations and an intuitive chromatogram analysis. Comparative analysis between TraceTrack and existing software tools highlights the advantages of TraceTrack with regards to batch processing, visualization and export functionalities.

Availability and implementation

TraceTrack is available at https://github.com/MSDLLCpapers/TraceTrack and as a web application at https://tracetrack.dichlab.org. TraceTrack is a web application for batch processing and visualization of Sanger trace file chromatograms that meets the increasing demand of industrial sequence validation workflows in pharmaceutical settings.

Supplementary information

Supplementary data are available at Bioinformatics Advances online.
(m, n)-mer—a simple statistical feature for sequence classification
Authors: de Andrade Amanda Araújo Serrão , Grivet Marco , Brustolini Otávio , Vasconcelos Ana Tereza Ribeiro
Published: July 2023

The (m, n)-mer is a simple alternative classification feature based on conditional probability distributions. In this application note, we compared k-mer and (m, n)-mer frequency features in 11 distinct datasets used for binary, multiclass and clustering classifications. Our findings show that the (m, n)-mer frequency features are related to the highest performance metrics and often statistically outperformed the k-mers. Here, the (m, n)-mer frequencies improved performance for classifying smaller sequence lengths (as short as 300 bp) and yielded higher metrics when using short values of k (ranging from 2 to 4). Therefore, we present the (m, n)-mers frequencies to the scientific community as a feature that seems to be quite effective in identifying complex discriminatory patterns and classifying polyphyletic sequence groups.

Availability and implementation

The (m, n)-mer algorithm is released as an R package within the CRAN project (https://cran.r-project.org/web/packages/mnmer) and is also available at https://github.com/labinfo-lncc/mnmer.

Supplementary information

Supplementary data are available at Bioinformatics Advances online.
Bold–shy continuum does not account for egg rejection behaviour in the Japanese tit
Authors: Shen Chao , Yu Jiangping , Yin Dake , Liu Qingzhen , Wang Haitao , Liang Wei
Published: July 2023

In response to brood parasitism, which significantly reduces the reproductive success of avian hosts, hosts have evolved the ability to recognize and reject parasitic eggs. Many studies have revealed the factors influencing egg recognition and egg rejection. Recent work has demonstrated that host personality along the bold–shy continuum can influence egg rejection behaviour. In addition, the egg rejection behaviour of hosts differs among populations, suggesting that individuals with different personalities might evolve various adaptive behaviours under different parasitic pressures, but there have been few relevant experiments to test this. In the present study, two populations of the Japanese tit, Parus minor, distributed in China were used to examine whether there were differences in egg rejection behaviour of individuals with different personalities. The results showed that egg rejection rates of bold individuals (which remained in the nest box when encountering human invaders) and shy individuals (which immediately flew away from the nest box when encountering human invaders) were similar in both populations of the Japanese tit, and there were also no significant differences in egg rejection rates between individuals of the same personality in the two populations. This study suggests that host personality along the bold–shy continuum does not account for egg rejection behaviour in Japanese tits. This might be attributable either to other factors that affect egg rejection behaviour counteracting the effect of personality or to the presence of multiple personality traits that act together in the Japanese tits, counteracting the effect of a single personality trait.
Peripherin is a biomarker of axonal damage in peripheral nervous system disease
Authors: Keddie Stephen , Smyth Duncan , Keh Ryan Y S , Chou Michael K L , Grant Donna , Surana Sunaina , Heslegrave Amanda , Zetterberg Henrik , Wieske Luuk , Michael Milou , Eftimov Filip , Bellanti Roberto , Rinaldi Simon , Hart Melanie S , Petzold Axel , Lunn Michael P
Published: July 2023

Valid, responsive blood biomarkers specific to peripheral nerve damage would improve management of peripheral nervous system (PNS) diseases. Neurofilament light chain (NfL) is sensitive for detecting axonal pathology but is not specific to PNS damage, as it is expressed throughout the PNS and CNS. Peripherin, another intermediate filament protein, is almost exclusively expressed in peripheral nerve axons. We postulated that peripherin would be a promising blood biomarker of PNS axonal damage.

We demonstrated that peripherin is distributed in sciatic nerve, and to a lesser extent spinal cord tissue lysates, but not in brain or extra-neural tissues. In the spinal cord, anti-peripherin antibody bound only to the primary cells of the periphery (anterior horn cells, motor axons and primary afferent sensory axons). In vitro models of antibody-mediated axonal and demyelinating nerve injury showed marked elevation of peripherin levels only in axonal damage and only a minimal rise in demyelination.

We developed an immunoassay using single molecule array technology for the detection of serum peripherin as a biomarker for PNS axonal damage. We examined longitudinal serum peripherin and NfL concentrations in individuals with Guillain-Barré syndrome (GBS, n = 45, 179 time points), chronic inflammatory demyelinating polyradiculoneuropathy (CIDP, n = 35, 70 time points), multiple sclerosis (n = 30), dementia (as non-inflammatory CNS controls, n = 30) and healthy individuals (n = 24).

Peak peripherin levels were higher in GBS than all other groups (median 18.75 pg/ml versus < 6.98 pg/ml, P < 0.0001). Peak NfL was highest in GBS (median 220.8 pg/ml) and lowest in healthy controls (median 5.6 pg/ml), but NfL did not distinguish between CIDP (17.3 pg/ml), multiple sclerosis (21.5 pg/ml) and dementia (29.9 pg/ml). While peak NfL levels were higher with older age (rho = +0.39, P < 0.0001), peak peripherin levels did not vary with age.

In GBS, local regression analysis of serial peripherin in the majority of individuals with three or more time points of data (16/25) displayed a rise-and-fall pattern with the highest value within the first week of initial assessment. Similar analysis of serial NfL concentrations showed a later peak at 16 days. Group analysis of serum peripherin and NfL levels in GBS and CIDP patients were not significantly associated with clinical data, but in some individuals with GBS, peripherin levels appeared to better reflect clinical outcome measure improvement.

Serum peripherin is a promising new, dynamic and specific biomarker of acute PNS axonal damage.
CDKL5 deficiency disorder: progressive brain atrophy may be part of the syndrome
Authors: Specchio Nicola , Trivisano Marina , Lenge Matteo , Ferretti Alessandro , Mei Davide , Parrini Elena , Napolitano Antonio , Rossi-Espagnet Camilla , Talenti Giacomo , Longo Daniela , Proietti Jacopo , Ragona Francesca , Freri Elena , Solazzi Roberta , Granata Tiziana , Darra Francesca , Bernardina Bernardo Dalla , Vigevano Federico , Guerrini Renzo
Published: July 2023

The clinical phenotype of Cyclin-Dependent Kinase-Like 5 (CDKL5) deficiency disorder (CDD) has been delineated but neuroimaging features have not been systematically analyzed. We studied brain magnetic resonance imaging (MRI) scans in a cohort of CDD patients and reviewed age at seizure onset, seizure semiology, head circumference. Thirty-five brain MRI from 22 unrelated patients were included. The median age at study entry was 13.4 years. In 14/22 patients (85.7%), MRI in the first year of life was unremarkable in all but two. In 11/22, we performed MRI after 24 months of age (range 2.5–23 years). In 8 out of 11 (72.7%), MRI showed supratentorial atrophy and in six cerebellar atrophy. Quantitative analysis detected volumetric reduction of the whole brain (−17.7%, P-value = 0.014), including both white matter (−25.7%, P-value = 0.005) and cortical gray matter (−9.1%, P-value = 0.098), with a reduction of surface area (−18.0%, P-value = 0.032), mainly involving the temporal regions, correlated with the head circumference (ρ = 0.79, P-value = 0.109). Both the qualitative structural assessment and the quantitative analysis detected brain volume reduction involving the gray and white matter. These neuroimaging findings may be related to either progressive changes due to CDD pathogenesis, or to the extreme severity of epilepsy, or both. Larger prospective studies are needed to clarify the bases for the structural changes we observed.
A Novel Method for Determination of Cyclobenzaprine in the Different Matrixes by UHPLC-DAD: Application to Real Human Plasma and Pharmaceutical Formulations
Authors: Akman Tugrul C
Published: July 2023

This study presents a novel and efficient method for determining of cyclobenzaprine (CBP) in human plasma and tablets using simple liquid–liquid microextraction and ultra-high performance liquid chromatography-diode-array detector. The developed method was optimized and validated for selectivity, linearity, precision, accuracy, limit of detection (LOD) and limit of quantification (LOQ). The chromatographic separation was achieved using a C18 column with a mobile phase consisting of a mixture of deionized water containing 0.1% TFA and methanol (30:70, v:v) at a flow rate of 1.0 mL/min. The extraction process provided high-efficiency recovery of CBP with a small plasma volume (%94.3). The method showed good linearity within the concentration range of 0.005–10 μg/mL, with a correlation coefficient of 0.999. The LOD and LOQ values were found to be 0.0013 and 0.005 μg/mL, respectively. The intra- and inter-day %RSD were <8%, and %RE were ranged from −0.50 to 0.01%. The proposed method was successfully applied to the analysis of CBP in real human plasma samples and tablets, indicating its applicability in clinical and pharmaceutical research. In conclusion, the simple, low cost, high sensitivity and rapid nature of this method make it an attractive option for the quantification of CBP in human plasma and pharmaceutical dosage forms.
Prognostic value of peripheral endothelial function on major adverse cardiovascular events above traditional risk factors
Authors: Rajai Nazanin , Toya Takumi , Sara Jaskanwal D , Rajotia Arush , Lopez-Jimenez Francisco , Lerman Lilach O , Lerman Amir
Published: July 2023

Aims

This study aims to identify whether adding peripheral microvascular dysfunction (PMED), a marker of atherosclerosis to established risk scores has an incremental prognostic value for major adverse cardiovascular events (MACE).

Methods and results

This is a retrospective study of patients who underwent measuring peripheral arterial tonometry from 2006 to 2020. The optimal cut-off value of the reactive hyperaemia index (RHI) that had maximal prognostic value associated with MACE was calculated. Peripheral microvascular endothelial dysfunction was defined as the RHI lower than the cut-off. Traditional cardiovascular risk factors such as age, sex, congestive heart failure, hypertension, diabetes, stroke, and vascular disease were determined to calculate the CHA2DS2-Vasc score. The outcome was MACE defined as myocardial infarction, heart failure hospitalization, cerebrovascular events, and all-cause mortality. A total of 1460 patients were enrolled (average age 51.4 ± 13.6, 64.1% female). The optimal cut-off value of the RHI was 1.83 in the overall population and in females and males was 1.61 and 1.8, respectively. The risk of MACE during 7 [interquartile range (IQR): 5,11] years of follow-up was 11.2%. Kaplan–Meier analysis showed that lower RHI is associated with worse MACE-free survival (P < 0.001). Multivariate Cox proportional hazard analysis, controlling for classic cardiovascular risk factors or risk scores such as CHA2DS2-Vasc and Framingham risk score revealed that PMED is an independent predictor of MACE.

Conclusion

Peripheral microvascular dysfunction predicts cardiovascular events. Non-invasive assessment of peripheral endothelial function may be useful in early detection and improving the stratification of high-risk patients for cardiovascular events.

Lay summary

Key findings
Appropriate exercise prescription in primary and secondary prevention of cardiovascular disease: why this skill remains to be improved among clinicians and healthcare professionals. A call for action from the EXPERT Network
Authors: Hansen Dominique , Coninx Karin , Beckers Paul , Cornelissen Véronique , Kouidi Evangelia , Neunhauserer Daniel , Niebauer Josef , Spruit Martijn A , Takken Tim , Dendale Paul
Published: July 2023

In Europe alone, on a yearly basis, millions of people need an appropriate exercise prescription to prevent the occurrence or progression of cardiovascular disease (CVD). A general exercise recommendation can be provided to these individuals (at least 150 min of moderate-intensity endurance exercise, spread over 3–5 days/week, complemented by dynamic moderate-intensity resistance exercise 2 days/week). However, recent evidence shows that this one size does not fit all and that individual adjustments should be made according to the patient’s underlying disease(s), risk profile, and individual needs, to maximize the clinical benefits of exercise. In this paper, we (i) argue that this general exercise prescription simply provided to all patients with CVD, or elevated risk for CVD, is insufficient for optimal CVD prevention, and (ii) show that clinicians and healthcare professionals perform heterogeneously when asked to adjust exercise characteristics (e.g. intensity, volume, and type) according to the patient’s condition, thereby leading to suboptimal CVD risk factor control. Since exercise training is a class 1A intervention in the primary and secondary prevention of CVD, the awareness of the need to improve exercise prescription has to be raised among clinicians and healthcare professionals if optimized prevention of CVD is ambitioned.
GWLD: an R package for genome-wide linkage disequilibrium analysis
Authors: Zhang Rong , Wu Huaxuan , Li Yasai , Huang Zehang , Yin Zongjun , Yang Cai-Xia , Du Zhi-Qiang
Published: July 2023

Linkage disequilibrium (LD) analysis is fundamental to the investigation of the genetic architecture of complex traits (e.g. human disease, animal and plant breeding) and population structure and evolution dynamics. However, until now, studies primarily focus on LD status between genetic variants located on the same chromosome. Moreover, genome (re)sequencing produces unprecedented numbers of genetic variants, and fast LD computation becomes a challenge. Here, we have developed GWLD, a parallelized and generalized tool designed for the rapid genome-wide calculation of LD values, including conventional D/D′, r2, and (reduced) mutual information (MI and RMI) measures. LD between genetic variants within and across chromosomes can be rapidly computed and visualized in either an R package or a standalone C++ software package. To evaluate the accuracy and speed of LD calculation, we conducted comparisons using 4 real datasets. Interchromosomal LD patterns observed potentially reflect levels of selection intensity across different species. Both versions of GWLD, the R package (https://github.com/Rong-Zh/GWLD/tree/master/GWLD-R) and the standalone C++ software (https://github.com/Rong-Zh/GWLD/tree/master/GWLD-C%2B%2B), are freely available on GitHub.