bluuebunny/crossref_metadata_2025 huggingface dataset:
Visualization of the Plasma Frequency by means of a Particle Simulation using a Normalized Periodic Model
Authors: Grunwald Joschka , Mercorelli Paolo
Published: January 2022

In plasmas the atoms are dissociated into ions and free electrons. Due to the high mobility of the electrons, plasmas are a vibrating medium. As a result, a plasma frequency can be determined, which is an important parameter for characterizing a material. In this study, the plasma frequency is to be visualized. For this purpose, a mathematical model will be set up to describe the electron kinetics. The electrons are briefly deflected with a force against the static ion background in order to examine the interaction between the particles in the form of electrostatic fields. The discretized equations are implemented in a numerical particle simulation to visualize the movement of the electrons. The Particle-In-Cell (PIC) method is used for this. A spatial mathematical grid is created on which the simulated particles are distributed in the cells. The equations of motion and field are then solved on this grid at different times.
Vision-Based Deep Learning Algorithm for Detecting Potholes
Authors: Gajjar K , Niekerk T van , Wilm Thomas , Mercorelli P
Published: January 2022

Potholes on roads pose a major threat to motorists. Driving over a pothole has the potential to cause serious damage to a vehicle, which in turn may result in fatal accidents. Currently, many pothole detection methods exist. However, these methods do not utilize deep learning techniques to detect a pothole in real-time, determine the location thereof and display its location on a map. The success of determining an effective pothole detection method, which includes the aforementioned deep learning techniques, is dependent on acquiring a large amount of data, including images of potholes. Once adequate data had been gathered, the images were processed and annotated. The next step was to determine which deep learning algorithms could be utilized. Three different models, including Faster R-CNN, SSD and YOLOv3 were trained on the custom dataset containing images of potholes to determine which network produces the best results for real-time detection. It was revealed that YOLOv3 produced the most accurate results and performed the best in real-time, with an average detection time of only 0.836 s per image. The final results revealed that a real-time pothole detection system, integrated with a cloud and maps service, can be created to allow drivers to avoid potholes.
Traffic noise prediction using machine learning and monte carlo data augmentation: a case study on the Patiala city in India
Authors: Singh Daljeet , Kaler Priyal , Lyall Ishita , Singh Aekamjot , Pannu H S
Published: January 2022

Traffic noise pollution is a serious problem in the modern urban areas especially to design new architecture of smart cities, highways, hospitals, schools for an efficient and healthy environment. To analyse this aspect, we have proposed a machine learning based prediction of sound pressure level on an original dataset collected in Patiala city in India. Vehicular traffic and sound pressure level data was collected on different sites in the city. A total of 502 data samples on the identified sites were obtained for the study. Further this data is augmented using Monte Carlo simulation to 10 times of its initial size and the Artificial Neural Networks (ANN) have been trained and compared with other Machine learning methods for the vehicular traffic noise prediction. The input parameters in the model are traffic volume Q, percentage of heavy vehicles P and the average speed of vehicles V and the output parameter is the equivalent continuous sound pressure level, Leq dB(A). The experimental results show ANN which is trained on the augmented data using Monte Carlo simulations outperforms other advanced methods making it an effective measure for vehicular traffic noise prediction to develop a healthy environment which is free of noise pollution.
Biometric Identification based on the Multidimensional Transient Functions of the Human Oculo-Motor System
Authors: Pavlenko Vitaliy , Shamanina Tetiana , Chori Vladysla
Published: January 2022

Recently, identification systems that use human biometric characteristics in solving the problem of access to information systems are becoming more common. The paper proposes a new method of biometric identification of users of computer systems based on the definition of integral Volterra models of the human oculomotor system (OMS) according to experimental research “input-output” using innovative technology of eye tracking. Developed in the Python IDLE programming environment software to identify OMS. Experimental studies of the OMS of two individuals were performed. Based on the data obtained using the TOBII PRO TX300 eye tracker, the transient functions of the first, second and third orders of the OMS are determined. There is a significant difference in the diagonal intersections of the transition functions of the second and third orders of the two individuals.
Cavitation characteristics and suppression research of refrigerant in capillary tube
Authors: Zhang Yu , Liu Yicai , Liu Shiyan , Yao Yao
Published: January 2022

Cavitation is easy to form and develop due to the large pressure drop during throttling in the refrigeration system. To effectively suppress the throttling cavitation phenomenon, an aerating method through bypass capillary is proposed. Based on the Homogeneous Equilibrium Mixture (HEM) model, the Schnerr-Sauer cavitation model and the Realizable k-ε turbulence model were adopted, and the throttling process in the capillary tube and transition tube was simulated by Fluent, and the pressure distribution and vapor volume fraction distribution in the capillary tube and transition tube were obtained for both original model and aerating model. Results show that after adopting the aerating technology, the vapor volume fraction at the capillary outlet is almost unchanged, while the vapor volume fraction in the transition tube is obviously increased, which indicates that the bubble collapsing phenomenon in the transition tube is weakened, and then realized the purpose of suppressing the cavitation effect.
Fault Diagnosis of Fracturing Vehicle Based on Local Mean Decomposition and Synchroextracting Transform
Authors: Chen Zhigang , Jiang Yunlong , Wang Yingying , Zhang Huaibin , He Qun
Published: January 2022

The power end of a fracturing truck is a key component that provides kinetic energy during pressure operations. Its vibration signal is collected during operation because of the complex working conditions and heavy loads, resulting in the collected signal being filled with a large amount of noise, for which it is difficult to perform effective fault feature extraction. To address this problem, a new fault diagnosis method is proposed. This method combines local mean decomposition (LMD) and synchroextracting transform (SET) for signal processing. First, LMD processing is done on the acquired signal to obtain several product function (PF) components. The cross-correlation coefficient and kurtosis value are used as references to select the true PF components. After that, the SET method is used to process the real PF components, extract the energy that is most correlated with the time-varying features of the signal, remove the fuzzy energy, improve the time-frequency resolution, and enhance the fault features contained in the signal to facilitate accurate fault diagnosis. Finally, the vibration signals collected from the power end of the fracturing vehicle are experimentally verified. The results show that the method can accurately extract the fault characteristics of bearing failure in the power end, and provide some useful reference for the diagnosis method of fracturing vehicle power system.
Design of multifunctional railway track inspection vehicle
Authors: Shan Wenju , Zhao Guodong
Published: January 2022

With the continuous construction of railway network, it is more and more important to maintain the operating state of railway track. Meanwhile, due to the rising departure density, the time available for maintenance is shortened, and the contradiction between operation and maintenance is becoming increasingly acute. In order to improve the efficiency of track maintenance, this paper proposes a multi-functional railway track comprehensive test platform, which can effectively integrate the existing track maintenance equipment, improve the maintenance kilometers per unit time, and puts forward a set of matching internet data management system, which has important practical value for improving the modernization of track operation.
Design of signal conditioning circuit at the output end of signal source based on AD9954
Authors: Yang Lei
Published: January 2022

The signal source based on DDS technology has the characteristics of high precision and high resolution, and is widely used in precision testing, instrumentation and other fields. However, interference signals such as high frequency harmonics and noise will inevitably appear in the output signal of the DDS chip, and even the sinusoidal signal generated by the DDS will be completely covered. This article takes ADI’s 14-bit high-precision DDS chip AD9954 as an example. I/V conversion and elliptic filter circuits are added to the output of the chip to obtain a pure sinusoidal signal. The rationality of the design is verified by multisim simulation software. This circuit provides strong support for the design and implementation of high-precision signal sources based on DDS.
Influences of Saponification Time on the Physical Properties of Mineral Oil-Based Magnetorheological Grease
Authors: Zhang Hansong , Hu Zhide. , Zhao Hujun , Wang Dawei , Lei Yulong
Published: January 2022

This study was conducted to investigate the influences of saponification time on the physical properties of mineral oil-based magnetorheological greases(MRGs). Three types of mineral oil-based MRG were prepared by applying different saponification time in this work. Then the physical properties, thermal stability and colloidal performance were tested. Besides, the micro-morphology was observed to analyze the microstructures of MRGs. The experimental results prove the formation of entanglement soap fibers micro-network. The oil separation on pressure and worked penetration of MRG decrease with the increase of saponification time, while the centrifugal stability becomes better. DSC-TG-DTG tests exhibit three endothermic peaks and reveal a double-stage thermal decomposition process. It also indicates that the MRG under 2 hours saponification has the smallest thermal decomposition and highest decomposition temperature, which demonstrates a good thermal stability.
Research on ultra-high cycle fatigue performance and reliability life analysis of TC4 by laser shock peening
Authors: Wang Bohan , Cheng Li , Wu Yuhang , Ding Junliang , Zhang Xiaobo
Published: January 2022

The ultra-high cycle fatigue performance of TC4 titanium alloy specimens under different laser power densities was carried out by an ultrasonic fatigue testing machine. The fatigue fracture mechanism was analyzed by scanning electron microscope (SEM), and the reliability of ultra-high cycle fatigue life was analyzed. The results show that the specimen fatigue performance is obviously improved after laser shock peening, and the fatigue fracture surface shows a transgranular quasi-cleavage cracking mode with facets on the surface or subsurface, corresponding to high cycle fatigue and ultra-high cycle fatigue, respectively. At the same time, the position of the crack origin zone shifts sideways. The ultra-high cycle fatigue life obeys both lognormal distribution and three-parameter Weibull distribution, and the influence of reliability and confidence on reliability life depends on the sensitivity of unilateral tolerance confidence factor to both. According to the p-γ-S-N fitting curves, it was concluded that the fatigue life is higher and the scatter is smaller under the power density of 3.42 GW/cm2, so it is the best impact parameter.
Analysis on the flow field of straddle monorail train gear box
Authors: Liu Yansheng , Xu Honghai
Published: January 2022

Taking the gearbox of straddle monorail train as the research object, reasonable simplification of the geometric structure of the gearbox. Based on incompressible gas-liquid two-phase flow in gearbox, the overlapping grid technology in STAR-CCM+ software is used to solve the internal flow field of the gearbox. The effects of gear forward rotation and initial oil injection on the mass flow rate of lubricating oil in each bearing inlet/return hole in the gearbox are studied and analyzed. The results show that: with the increase of the initial oil injection rate, the mass flow rate of the oil inlet hole of each bearing increases; The positive and reverse rotation has a great influence on the mass flow rate of lubricating oil in each bearing intake hole. In the case of the same amount of oil injection, the mass flow rate of each intake hole in forward rotation is larger than that in reverse condition. The results of this research provide a theoretical basis for the detailed structure design and improvement of lubricating oil runner in gearbox.
Construction of Three-dimensional Co-continuous Composites with Controllable Volume Fraction
Authors: Han Huimin , Zhou Han , Zhou Jingwen
Published: January 2022

Efficient and low-cost manufacturing methods and adjustable properties are an important way to further promote the application of co-continuous composites. In this paper, a three-dimensional co-continuous composites model with controllable volume fraction is designed. The model uses triply periodic minimal surface (TPMS) as the internal structure and spatial segmentation strategy to accurately control the volume proportion of each phase, which enriches the three-dimensional modeling method of co-continuous composites and provides new ideas and methods for the wide application of co-continuous composites with adjustable characteristics. Finally, samples are manufactured through efficient and low-cost 3D printing technology.
Metallization of Through-Silicon-Via in 2.5D Interposers by Cold Plasma Jet
Authors: Zeng Wanshu , Yu Yao , Xia Weisheng
Published: January 2022

We proposed a cold capacitively-coupled-plasma jet method to deposit the seed layer in the inner wall of Through-silicon-vias (TSVs) directly. Comparison experiments were carried out to optimize the process parameters. The testing results were discussed and proved the potential application of this technique in the metallization of TSVs in 2.5D integration technology.
Simulation Calculation of Strip Descaling Based on Birth-Death Element Method
Authors: Wang Shang , Zhao Jianwei , He Hainan , Wang Xiaochen
Published: January 2022

In order to more accurately simulate the descaling process, a three-dimensional finite element model is established by ABAQUS based on the birth-death element method (BDEM). The model simulation results show that with the help of BDEM decision rules, the scale layer elements are continually deleted after reaching the failure threshold, and descaling process is accurately simulated. The maximum Mises stress at different times shows the law of random fluctuation, which is consistent with the working principle of BDEM. Increasing the number of iterations of the model and refining the local mesh can improve simulation effect of the model, but it will also increase the total amount of operation and total operation time.
Static and modal analysis of industrial robots
Authors: Sun Hongwei , Liu Chao , Zhang Benshun , Chen Yiming , Zhao Sibo , Li Chengdong
Published: January 2022

As an important automation equipment in contemporary manufacturing industry, 5-axis industrial robot is an important part of automated production. It improves the quality of work and production efficiency, reduces the workload of workers and lowers production costs. The development of industrial robots has a profound impact on China’s goal of being among the world’s manufacturing powerhouses in the first half of the 21st century. This paper presents a finite element analysis of the overall system of a five-axis intelligent robot for industrial use. The main focus is on optimizing the mechanical structure of the five-axis intelligent robot for industrial use, and the external structure of the key support components of the robot is simplified to create the model. Hazardous stress states were selected for the system analysis, a static analysis was implemented for each component to obtain the displacement and stresses corresponding to them, the maximum deformation of the key parts of the robot was obtained, and finally its stiffness was evaluated. Then the modal analysis is performed on this robot model, and the modal vibration clouds of the first 6 orders are selected to study the vibration patterns to obtain the corresponding frequencies, which provides data support for the robot to avoid working at resonant frequencies and provides a theoretical basis for improving its overall structure.
Research on cloud service selection based on rough set theory
Authors: Zhou Kaijun , Wang Qian , Gu Feng
Published: January 2022

Cloud manufacturing adopts contemporary information cutting-edge technologies including advanced concepts such as cloud computing to support the manufacturing industry. Under a wide range of network resource manufacturing environments, it can add high value-added products, reduce costs, and meet globalization. The optimization of cloud manufacturing services is based on the attributes of cloud manufacturing services as evaluation indicators, and corresponding optimization strategies are formulated to ensure the selection process of manufacturing services. Taking into account the uncertainty of cloud service, rough set is used to assign the weight to each evaluation index and furthermore solve the cloud manufacturing service selection. Finally, an example is used to verify the effectiveness of the proposed method.
The performance of a new Kuraray wavelength shifting fiber YS-2
Authors: Alekseev I. , Danilov M. , Rusinov V. , Samigullin E. , Svirida D. , Tarkovsy E.
Published: January 2022

Wavelength shifting fibers are widely used for light
collection from scintillation counters, which allow connection of
various scintillation planes to relatively small photocathodes of
photodetectors and especially tiny photocathodes of silicon
photo-multipliers. In October 2020 Kuraray announced production of
a new branch of faster fibers. We performed a comparison of the new
fiber YS-2 to a mature Y-11. The fiber YS-2 demonstrated decay time
nearly two times shorter than that of Y-11: ≈4.0 ns versus
≈7.4 ns. At the same time its light yield and attenuation
length are as good as of Y-11, which makes YS-2 a good choice for
timing scintillation detectors.
The future distribution of wetland birds breeding in Europe validated against observed changes in distribution
Authors: Soultan Alaaeldin , Pavón-Jordán Diego , Bradter Ute , Sandercock Brett K , Hochachka Wesley M , Johnston Alison , Brommer Jon , Gaget Elie , Keller Verena , Knaus Peter , Aghababyan Karen , Maxhuni Qenan , Vintchevski Alexandre , Nagy Károly , Raudonikis Liutauras , Balmer Dawn , Noble David , Leitão Domingos , Øien Ingar Jostein , Shimmings Paul , Sultanov Elchin , Caffrey Brian , Boyla Kerem , Radišić Dimitrije , Lindström Åke , Velevski Metodija , Pladevall Clara , Brotons Lluís , Karel Šťastný , Rajković Draženko Z , Chodkiewicz Tomasz , Wilk Tomasz , Szép Tibor , van Turnhout Chris , Foppen Ruud , Burfield Ian , Vikstrøm Thomas , Mazal Vlatka Dumbović , Eaton Mark , Vorisek Petr , Lehikoinen Aleksi , Herrando Sergi , Kuzmenko Tatiana , Bauer Hans-Günther , Kalyakin Mikhail V , Voltzit Olga V , Sjeničić Jovica , Pärt Tomas
Published: January 2022

Wetland bird species have been declining in population size worldwide as climate warming and land-use change affect their suitable habitats. We used species distribution models (SDMs) to predict changes in range dynamics for 64 non-passerine wetland birds breeding in Europe, including range size, position of centroid, and margins. We fitted the SDMs with data collected for the first European Breeding Bird Atlas and climate and land-use data to predict distributional changes over a century (the 1970s–2070s). The predicted annual changes were then compared to observed annual changes in range size and range centroid over a time period of 30 years using data from the second European Breeding Bird Atlas. Our models successfully predicted ca. 75% of the 64 bird species to contract their breeding range in the future, while the remaining species (mostly southerly breeding species) were predicted to expand their breeding ranges northward. The northern margins of southerly species and southern margins of northerly species, both, predicted to shift northward. Predicted changes in range size and shifts in range centroids were broadly positively associated with the observed changes, although some species deviated markedly from the predictions. The predicted average shift in core distributions was ca. 5 km yr−1 towards the north (5% northeast, 45% north, and 40% northwest), compared to a slower observed average shift of ca. 3.9 km yr−1. Predicted changes in range centroids were generally larger than observed changes, which suggests that bird distribution changes may lag behind environmental changes leading to ‘climate debt’. We suggest that predictions of SDMs should be viewed as qualitative rather than quantitative outcomes, indicating that care should be taken concerning single species. Still, our results highlight the urgent need for management actions such as wetland creation and restoration to improve wetland birds’ resilience to the expected environmental changes in the future.
Plausible 2005–2050 emissions scenarios project between 2 °C and 3 °C of warming by 2100
Authors: Pielke Jr Roger , Burgess Matthew G , Ritchie Justin
Published: January 2022

Emissions scenarios used by the Intergovernmental Panel on Climate Change (IPCC) are central to climate change research and policy. Here, we identify subsets of scenarios of the IPCC’s 5th (AR5) and forthcoming 6th (AR6) Assessment Reports, including the Shared Socioeconomic Pathway scenarios, that project 2005–2050 fossil-fuel-and-industry (FFI) CO2 emissions growth rates most consistent with observations from 2005 to 2020 and International Energy Agency (IEA) projections to 2050. These scenarios project between 2 °C and 3 °C of warming by 2100, with a median of 2.2 °C. The subset of plausible IPCC scenarios does not represent all possible trajectories of future emissions and warming. Collectively, they project continued mitigation progress and suggest the world is presently on a lower emissions trajectory than is often assumed. However, these scenarios also indicate that the world is still off track from limiting 21st-century warming to 1.5 °C or below 2 °C.
An optical pascal in Sweden
Authors: Forssén C , Silander I , Zakrisson J , Zelan M , Axner O
Published: January 2022

By measuring the refractivity and the temperature of a gas, its pressure can be assessed from fundamental principles. The highest performing instruments are based on Fabry–Perot cavities where a laser is used to probe the frequency of a cavity mode, which is shifted in relation to the refractivity of the gas in the cavity. Recent activities have indicated that such systems can demonstrate an extended uncertainty in the 10 ppm (parts-per-million or 10−6) range. As a means to reduce the influence of various types of disturbances (primarily drifts and fluctuations) a methodology based on modulation, denoted gas modulation refractometry (GAMOR), has recently been developed. Systems based on this methodology are in general high-performance, e.g. they have demonstrated precision in the sub-ppm range, and they are sturdy. They can also be made autonomous, allowing for automated and unattended operation for virtually infinite periods of time. To a large degree, the development of such instruments depends on the access to modern photonic components, e.g. narrow line-width lasers, electro- and acousto-optic components, and various types of fiber components. This work highlights the role of such modern devices in GAMOR-based instrumentation and provides a review on the recent development of such instruments in Sweden that has been carried out in a close collaboration between a research institute and the Academy. It is shown that the use of state-of-the-art photonic devices allows sturdy, automated and miniaturized instrumentation that, for the benefit of industry, can serve as standards for pressure and provide fast, unattended, and calibration-free pressure assessments at a fraction of the present cost.
Dynamic characteristics of multi-arc thermal plasma in four types of electrode configurations
Authors: ZHAO Yanjun , NI Guohua , LIU Wei , SUN Hongmei , SUI Siyuan , LI Dongdong , ZHENG Huan , MA Zhongyang , ZHANG Chi
Published: January 2022

The enhanced volume of thermal plasma is produced by a multi-arc thermal plasma generator with three pairs of discharge electrodes driven by three directed current power suppliers. Combined with a high-speed camera and an oscilloscope, which acquire optical and electric signals synchronously, the dynamic behavior of different kinds of multi-arc discharge adjusted by the electrode arrangement is investigated. Also, the spatial distributions and instability of the arc discharge are analyzed in four electrode configurations using the gray value statistical method. It is found that the cathodic arcs mainly show a contracting state, while the anodic arcs have a trend of transition from shrinkage to a diffusion-like state with the increase of the discharge current. As a result of the adjustment of the electrode configuration, a high temperature region formed in the center of the discharge region in configurations of adjacent electrodes with opposite flow distribution and opposite electrodes with swirl flow distribution due to severe fluctuation of arcs. The discharge voltage rises with increased discharge current in this novel multi-arc plasma generator. It is also found that anode ablation mainly occurs on the conical surface at the copper electrode tip, while cathode erosion mainly occurs on the surface of the inserted tungsten and the nearby copper.
‘The worse my hearing got, the less sociable I got’: a qualitative study of patient and professional views of the management of social isolation and hearing loss
Authors: Heffernan Eithne , Withanachchi Christine M , Ferguson Melanie A
Published: January 2022

Background

Social isolation is a major consequence of hearing loss. It includes an objective component (e.g. small social network) and a subjective component (e.g. loneliness).

Objective

To examine the perspectives of key stakeholders regarding (i) the relationship between hearing loss and social isolation and (ii) interventions to address hearing loss and social isolation.

Design

A phenomenological qualitative study.

Setting

A UK research centre with a role to engage patients and clinicians.

Participants

Hearing healthcare professionals (n = 7) and adults with hearing loss (n = 6) were recruited via maximum variation sampling.

Methods

Individual (n = 3) and group (n = 3) semi-structured interviews were conducted. Inductive thematic analysis was performed.

Results

Five themes were identified. Theme 1 (experience of isolation and hearing loss): hearing loss can cause people to feel disconnected at social events or to cease attending them. Theme 2 (complexity of isolation and hearing loss): the various causes of isolation (e.g. hearing loss, retirement, comorbidities) are difficult to disentangle. Theme 3 (downstream effects of isolation and hearing loss): hearing loss and/or isolation can lead to mental health problems, stigmatisation, fatigue and unemployment. Theme 4 (preferred components of an isolation intervention): an isolation intervention should be patient-led and patient-centred and take place in the community. Theme 5 (challenges to implementing an isolation intervention): barriers to implementing an isolation intervention include a lack of time, training and continuity.

Conclusion

This study demonstrated that social isolation arising from hearing loss is a substantial, complex problem and provided novel insights on implementing an intervention to address this issue.
Frailty in the oldest old: is the current level or the rate of change more predictive of mortality?
Authors: Stolz Erwin , Mayerl Hannes , Hoogendijk Emiel O
Published: January 2022

Background

It is unclear whether frailty index (FI) change captures mortality risk better than and independently of the current FI level, i.e. whether a regular FI assessment among older adults provides additional insights for mortality risk stratification or not.

Methods

We used data from the LASA 75-PLUS-study, which monitored health among 508 older adults (75+) between 2016 and 2019 every 9 months. Joint models for longitudinal and time-to-event data were used to assess the impact of both current FI and within-person FI change during the last year on mortality risk.

Results

Twenty percent of the participants died during 4.5 years of follow-up. Adding within-person FI change to the current FI model improved model fit and it showed that FI increases during the last year were associated with an increase in mortality risk. Consequently, the effect of the current FI decreased considerably and became statistically non-significant.

Conclusions

The rate of FI change was more important than the current FI level for short-term mortality prediction among the oldest old, which highlights the benefits of regular frailty assessments.
Ecology of fear and its effect on seed dispersal by a neotropical rodent
Authors: Gálvez Dumas , Hernández Marisol
Published: January 2022

Predators exert negative effects on prey, besides the act of killing, generating behavioral and physiological costs, a concept known as the ecology of fear. Studies in scatter-hoarding rodents in temperate zones suggests that prey use habitat structure to perceive predation risk. Less is known about how tropical forest rodents perceive predation risk. Here, we investigated whether the Central American agouti perceive predation risk by ocelots through olfactory cues and whether it influences the foraging behavior for Attalea butyracea seeds, one of its main food sources. By monitoring tagged seeds, we found that seed dispersal and pilferage was lower in sites with high density of ocelots, in line with the predictions of ecology of fear proposing that scared animals eat less. We also found that pilferage rates in high ocelot density sites seem to be lower during the rainy—transition period but not during dry season when food availability is generally low. However, we did not find evidence that agoutis adjust their cache spacing behavior in response to ocelot density. In an additional experiment to corroborate that agoutis’ responses were caused by ocelots’ cues, we found lower dispersal rates for seeds placed next to samples of urine and feces of ocelots as compared to controls, during the first seven days. Moreover, agoutis spent less time handling the seeds with ocelots’ cues. Here, we discuss potential cascading effects linked to the behavior of agoutis towards predation risk.
Propofol selectively modulates functional connectivity signatures of sustained attention during rest and narrative listening
Authors: Chamberlain Taylor A , Rosenberg Monica D
Published: January 2022

Sustained attention is a critical cognitive function reflected in an individual’s whole-brain pattern of functional magnetic resonance imaging functional connectivity. However, sustained attention is not a purely static trait. Rather, attention waxes and wanes over time. Do functional brain networks that underlie individual differences in sustained attention also underlie changes in attentional state? To investigate, we replicate the finding that a validated connectome-based model of individual differences in sustained attention tracks pharmacologically induced changes in attentional state. Specifically, preregistered analyses revealed that participants exhibited functional connectivity signatures of stronger attention when awake than when under deep sedation with the anesthetic agent propofol. Furthermore, this effect was relatively selective to the predefined sustained attention networks: propofol administration modulated strength of the sustained attention networks more than it modulated strength of canonical resting-state networks and a network defined to predict fluid intelligence, and the functional connections most affected by propofol sedation overlapped with the sustained attention networks. Thus, propofol modulates functional connectivity signatures of sustained attention within individuals. More broadly, these findings underscore the utility of pharmacological intervention in testing both the generalizability and specificity of network-based models of cognitive function.
Abnormal dynamics of resting-state functional activity and couplings in postpartum depression with and without anxiety
Authors: Cheng Bochao , Wang Xiuli , Roberts Neil , Zhou Yushan , Wang Song , Deng Pengcheng , Meng Yajing , Deng Wei , Wang Jiaojian
Published: January 2022

Postpartum depression (PPD) and PPD comorbid with anxiety (PPD-A) are highly prevalent and severe mental health problems in postnatal women. PPD and PPD-A share similar pathopsychological features, leading to ongoing debates regarding the diagnostic and neurobiological uniqueness. This paper aims to delineate common and disorder-specific neural underpinnings and potential treatment targets for PPD and PPD-A by characterizing functional dynamics with resting-state functional magnetic resonance imaging in 138 participants (45 first-episode, treatment-naïve PPD; 31 PDD-A patients; and 62 healthy postnatal women [HPW]). PPD-A group showed specifically increased dynamic amplitude of low-frequency fluctuation in the subgenual anterior cingulate cortex (sgACC) and increased dynamic functional connectivity (dFC) between the sgACC and superior temporal sulcus. PPD group exhibited specifically increased static FC (sFC) between the sgACC and ventral anterior insula. Common disrupted sFC between the sgACC and middle temporal gyrus was found in both PPD and PPD-A patients. Interestingly, dynamic changes in dFC between the sgACC and superior temporal gyrus could differentiate PPD, PPD-A, and HPW. Our study presents initial evidence on specifically abnormal functional dynamics of limbic, emotion regulation, and social cognition systems in patients with PDD and PPD-A, which may facilitate understanding neurophysiological mechanisms, diagnosis, and treatment for PPD and PPD-A.
The effects of epigenetic age and its acceleration on surface area, cortical thickness, and volume in young adults
Authors: Cheong Yongjeon , Nishitani Shota , Yu Jinyoung , Habata Kaie , Kamiya Taku , Shiotsu Daichi , Omori Ichiro M , Okazawa Hidehiko , Tomoda Akemi , Kosaka Hirotaka , Jung Minyoung
Published: January 2022

DNA methylation age has been used in recent studies as an epigenetic marker of accelerated cellular aging, whose contribution to the brain structural changes was lately acknowledged. We aimed to characterize the association of epigenetic age (i.e. estimated DNA methylation age) and its acceleration with surface area, cortical thickness, and volume in healthy young adults. Using the multi-tissue method (Horvath S. DNA methylation age of human tissues and cell types. 2013. Genome Biol 14), epigenetic age was computed with saliva sample. Epigenetic age acceleration was derived from residuals after adjusting epigenetic age for chronological age. Multiple regression models were computed for 148 brain regions for surface area, cortical thickness, and volume using epigenetic age or accelerated epigenetic age as a predictor and controlling for sex. Epigenetic age was associated with surface area reduction of the left insula. It was also associated with cortical thinning and volume reduction in multiple regions, with prominent changes of cortical thickness in the left temporal regions and of volume in the bilateral orbital gyri. Finally, accelerated epigenetic age was negatively associated with right cuneus gyrus volume. Our findings suggest that understanding the mechanisms of epigenetic age acceleration in young individuals may yield valuable insights into the relationship between epigenetic aging and the cortical change and on the early development of neurocognitive pathology among young adults.
Direct and Indirect Effects of the Coronavirus Disease 2019 Pandemic on Private Healthcare Utilization in South Africa, March 2020–September 2021
Authors: Perofsky Amanda C , Tempia Stefano , Bingham Jeremy , Maslo Caroline , Toubkin Mande , Laubscher Anchen , Walaza Sibongile , Pulliam Juliet R C , Viboud Cécile , Cohen Cheryl
Published: January 2022

Background

The coronavirus disease 2019 (COVID-19) pandemic caused severe disruptions to healthcare in many areas of the world, but data remain scarce for sub-Saharan Africa.

Methods

We evaluated trends in hospital admissions and outpatient emergency department (ED) and general practitioner (GP) visits to South Africa’s largest private healthcare system during 2016–2021. We fit time series models to historical data and, for March 2020–September 2021, quantified changes in encounters relative to baseline.

Results

The nationwide lockdown on 27 March 2020 led to sharp reductions in care-seeking behavior that persisted for 18 months after initial declines. For example, total admissions dropped 59.6% (95% confidence interval [CI], 52.4–66.8) during home confinement and were 33.2% (95% CI, 29–37.4) below baseline in September 2021. We identified 3 waves of all-cause respiratory encounters consistent with COVID-19 activity. Intestinal infections and non–COVID-19 respiratory illnesses experienced the most pronounced declines, with some diagnoses reduced 80%, even as nonpharmaceutical interventions (NPIs) relaxed. Non-respiratory hospitalizations, including injuries and acute illnesses, were 20%–60% below baseline throughout the pandemic and exhibited strong temporal associations with NPIs and mobility. ED attendances exhibited trends similar to those for hospitalizations, while GP visits were less impacted and have returned to pre-pandemic levels.

Conclusions

We found substantially reduced use of health services during the pandemic for a range of conditions unrelated to COVID-19. Persistent declines in hospitalizations and ED visits indicate that high-risk patients are still delaying seeking care, which could lead to morbidity or mortality increases in the future.
Information rents, economic growth and inequality: an empirical study of the United States
Authors: Rotta Tomas N
Published: January 2022

In this paper, I estimate the impact of unproductive activities on economic growth, labour productivity and income inequality in the United States from 1947 to 2011. Productive activities directly create value, while unproductive activities do not. I develop a new methodology to compute the growth of productive and unproductive activities in terms of flows of income and stocks of fixed assets using input-output matrices and national income accounts. A core feature of my methodology is the notion that the commodification of knowledge and information gives rise to ‘information rents’. Information rents are, as I demonstrate, a determinant factor of growth and distribution. I find that unproductive activities have a net positive effect on economic growth and labour productivity, but at the price of increasing income inequality. Unproductive activities that rely on information rents, in particular, have increased income inequality and slowed down value-added growth despite their positive contribution to labour productivity. Information rents have drawn too much value from productive activities and benefitted the top income earners.
Linear Attacks On SNOW 3G And SNOW-V Using Automatic Search
Authors: Shi Zhen , Jin Chenhui
Published: January 2022

In this paper, a linear attack model of SNOW 3G and SNOW-V based on automatic search technology is proposed. We first describe the linear approximation of Finite State Machine transformation, which allows a wider range of automatic search, then model it with the automatic search technology based on SAT/SMT program. Adopting this generic method, we seek out a binary linear approximation of SNOW 3G with correlation of $2^{-21.92}$ which has been verified by test. Treating this binary approximation as a mask of an 8-bit distribution in a fixed field, we provide a method to obtain the 8-bit distribution. The binary approximation is used in a fast correlation attack with expected time and memory complexity $2^{184.67}$, given $2^{173.96}$ key stream words. For the full version of SNOW-V, considering the linear relationship between Linear Feedback Shift Register parts at three successive moments, we search out a distinguisher with correlation of $2^{-175.51}$, which results in a distinguishing attack with an expected complexity of $2^{351.02}$.
Management and Long-term Outcomes of Crohn’s Disease Complicated with Enterocutaneous Fistula: ECUFIT Study from GETECCU
Authors: Barreiro-de Acosta Manuel , Riestra Sabino , Calafat Margalida , Soto María Pilar , Calvo Marta , Sánchez Rodríguez Eugenia , Caballol Berta , Vela Milagros , Rivero Montserrat , Muñoz Fernando , de Castro Luisa , Calvet Xavier , García-Alonso Francisco Javier , Utrilla Fornals Alejandra , Ferreiro-Iglesias Rocío , González-Muñoza Carlos , Chaparro María , Bujanda Luis , Sicilia Beatriz , Alfambra Erika , Rodríguez Andrés , Pérez Fernández Rubén , Rodríguez Cristina , Almela Pedro , Argüelles Federico , Busquets David , Tamarit-Sebastián Sonsoles , Reygosa Castro Cristina , Jiménez Laura , Marín-Jiménez Ignacio , Alcaide Noelia , Fernández-Salgado Estela , Iglesias Águeda , Ponferrada Ángel , Pajares Ramón , Roncero Óscar , Morales-Alvarado Víctor Jair , Ispízua-Madariaga Nahia , Sáinz Empar , Merino Olga , Márquez-Mosquera Lucía , García-Sepulcre Mariana , Elorza Ainara , Estrecha Sandra , Surís Gerard , Van Domselaar Manuel , Brotons Alicia , de Francisco Ruth , Cañete Fiorella , Iglesias Eva , Vera María Isabel , Mesonero Francisco , Lorente Rufo , Zabana Yamile , Cabriada José Luis , Domènech Eugeni , Rodríguez-Lago Iago
Published: January 2022

Background and aims

Crohn’s disease [CD] can develop penetrating complications at any time during the disease course. Enterocutaneous fistulae [ECF] are disease-related complications with an important impact on quality of life. Our aim was to describe the outcomes of this complication, including its medical and/or surgical management and their temporal trends. The primary endpoint was fistula closure, defined as the absence of drainage, with no new abscess or surgery, over the preceding 6 months.

Methods

Clinical information from all adult patients with CD and at least one ECF—excluding perianal fistulae—were identified from the prospectively-maintained ENEIDA registry. All additional information regarding treatment for this complication was retrospectively reviewed.

Results

A total of 301 ECF in 286 patients [January 1970-September 2020] were analysed out of 30 088 records. These lesions were mostly located in the ileum [67%] and they had a median of one external opening [range 1-10]. After a median follow-up of 146 months (interquartile range [IQR], 69-233), 69% of patients underwent surgery. Fistula closure was achieved in 84%, mostly after surgery, and fistula recurrence was uncommon [13%]. Spontaneous and low-output fistulae were associated with higher closure rates (hazard ratio [HR] 1.51, 95% confidence interval [CI] 1.17-1.93, p = 0.001, and HR 1.49, 95% CI 1.07-2.06, p = 0.03, respectively); this was obtained more frequently with medical therapy since biologics have been available.

Conclusions

ECF complicating CD are rare but entail a high burden of medical and surgical resources. Closure rates are high, usually after surgery, and fistula recurrence is uncommon. A significant proportion of patients receiving medical therapy can achieve fistula closure.
Evaluation of palatal bone depth, cortical bone, and mucosa thickness for optimal orthodontic miniscrew placement performed according to the third palatal ruga clinical reference
Authors: Nucera Riccardo , Costa Stefania , Bellocchio Angela Mirea , Barbera Serena , Drago Sara , Silvestrini Armando , Migliorati Marco
Published: January 2022

Objectives

This retrospective CBCT study aimed to evaluate the palatal anatomical characteristics using the third palatal ruga as a reliable clinical reference for miniscrew placement.

Methods

Thirty-six subjects (mean age17.1 y.o. ± 4.1) were randomly selected and their records (CBCT volume and maxillary digital models) were included.

BlueSkyPlan CBCT software viewer (BluSkyBio, V4.7) was used to measure the following outcomes at the level of third palatal ruga, 2 mm anteriorly and 2 mm posteriorly: total bone depth, cortical bone thickness, and mucosa thickness. The outcomes were evaluated on lines perpendicular to the palatal mucosa laying on different sagittal planes: the mid-palatal plane, 2 and 4 mm paramedian planes.

Results

The maximum mean amount of bone depth was registered 2 mm posteriorly to the third ruga and 4 mm paramedian (9.7 mm). No significant difference was observed between the third ruga insertion site and its corresponding 2 mm posterior site. Cortical bone of palatal vault did not change significantly in anteroposterior direction for all the considered sites. Significant differences were found comparing cortical bone at the suture level with cortical bone 2-mm and 4-mm paramedian at all anteroposterior levels. Palatal mucosa increases its thickness in paramedian insertion sites, and it decreases in posterior insertion sites.

Conclusions

Both third palatal ruga and 2 mm posteriorly to third ruga (4 mm paramedian) could be the optimal insertion site for palatal miniscrew placement, depending on individual anatomic conditions. The thickness of the cortical palatal bone showed, at 4 mm paramedian, optimal characteristics for miniscrew primary stability. Palatal mucosa thickness values suggest miniscrew neck extension of 2.0–2.5 mm for optimal mucosa adaptation.