bluuebunny/crossref_metadata_2025 huggingface dataset:
Behavioral Indicator-Based Initial Flight Training Competency Assessment Model
Authors: Sun Hong , Yang Fangquan , Zhang Peiwen , Hu Qingqing
Published: May 2023

Ensuring training safety is paramount to flight schools. In response to the inadequacy of traditional flight training assessment for comprehensive quantitative evaluation of cadet competency, an initial flight training competency assessment standard based on behavioral indicators was developed and optimized using the VENN model. Firstly, the Assessor Score Measurement Form (ASMF) was constructed according to the requirements of the Training Evaluation Worksheet specification, such as typical subjects, observations, and completion criteria. Secondly, based on the basic principles of the experience of the flight expert and the Competency-Based Training and Assessment (CBTA), a matrix of correlations between the observations and each competency-based behavioral indicator was created to construct a competency assessment matrix. In addition, a two-dimensional model for representing competency items characterized by behavioral indicators was established and an optimization model for competency assessment criteria was constructed. Finally, through combining actual flight training data, the proposed method was validated in the flight screening check phase. The results show that the optimized flight training competency assessment scheme can be well quantified and matched to real instructor ratings with an accuracy of 84%. The assessment worksheet, the assessment matrix, and the VENN competency rating model can be adapted to the different teaching requirements of each flight phase, achieving a perfect match between the behavioral indicators and the competency items, which is highly versatile. The proposed model can more accurately reflect the core competencies of flight trainees, enable quantitative assessment of behavioral indicators and competency items, and provide support for subsequent training of trainees.
Centrifugal Model Study of Seepage and Seismic Behavior in a Homogeneous Reservoir Dam with Parapet
Authors: Lee Young-Hak , Yamakawa Soichiro , Tobita Tetsuo , Hong Hyuk-Kee , Song Hyo-Sung , Kim Jae-Jung , Lee Dal-Won
Published: May 2023

This study examines the effectiveness of parapets in preventing overtopping failures of small-scale homogeneous reservoir dams under seismic loads. In this study, a parapet covered the entire width of the dam crest and was designed to ensure its weight is transmitted to the dam crest. The test included four modes: initial mode, first seepage, seismic, and second seepage. The results show that without parapets the crack length and width expand significantly in the dam crest during the seismic mode, and the effect was large in the second seepage mode. The crack depth increased by 11.3–24 times during the seismic mode and expanded up to 73.3% of the dam height in the longitudinal direction along the axis of the crack formed in the dam crest during the second seepage mode. These findings suggest that the earthquake weakened the dam body, making it vulnerable to penetration. In contrast, the parapet structure effectively suppressed most of the tensile cracks by increasing the constraint force. Additionally, no crack expansion or tearing occurred during the second seepage mode post-earthquake, indicating improved seismic performance and suppression of seepage deformation.
Challenges and Recommendations for Improved Identification of Low ILUC-Risk Agricultural Biomass
Authors: Sandford Cato , Malins Chris , Panoutsou Calliope
Published: May 2023

The “low indirect land use change risk” (“low ILUC-risk”) concept was developed to assess whether crop-based biofuels would compete with other land uses and cause the expansion of agricultural land. At the core of low ILUC-risk is an “additionality principle”, which requires that biofuel feedstock receive special treatment only if it is produced over and above the business-as-usual baseline. This paper examines and tests the European Commission’s methodology for calculating the baseline for yield improvement projects, by applying it to publicly available Eurostat data at national and NUTS2 scales. We assess from a statistical perspective how variation in regional yield trends would lead to differences in the long-term outcomes of low ILUC-risk certification; we conclude that, as currently designed, the methodology would over-state the amount of additional production in some cases and could hence incentivise the diversion of crops from other uses into the biofuel sector. We introduce the terms “tailwind additionality”, “headwind additionality”, and “additionality ratchet” to characterise the phenomena which contribute to this outcome. Our results lead us to recommendations which may enhance both the attractiveness and the robustness of the low ILUC-risk system.
Objective Prediction of Human Visual Acuity Using Image Quality Metrics
Authors: Tomás Julián Espinosa , Rodríguez Jorge Pérez , Candela David Más , Ferri Carmen Vázquez , Perales Esther
Published: May 2023

This work addresses the objective prediction of human uncorrected decimal visual acuity, an unsolved challenge due to the contribution of both physical and neural factors. An alternative approach to assess the image quality of the human visual system can be addressed from the image and video processing perspective. Human tolerance to image degradation is quantified by mean opinion scores, and several image quality assessment algorithms are used to maintain, control, and improve the quality of processed images. The aberration map of the eye is used to obtain the degraded theoretical image from a set of natural images. The amount of distortion added by the eye to the natural image was quantified using different image processing metrics, and the correlation between the result of each metric and subjective visual acuity was assessed. The correlation obtained for a model based on a linear combination of the normalized mean square error metric and the feature similarity index metric was very good. It was concluded that the proposed method could be an objective way to determine subjects’ monocular and uncorrected decimal visual acuity with low uncertainty.
Simulating Atmospheric Characteristics and Daytime Astronomical Seeing Using Weather Research and Forecasting Model
Authors: Shikhovtsev A. Y. , Kovadlo P. G. , Lezhenin A. A. , Gradov V. S. , Zaiko P. O. , Khitrykau M. A. , Kirichenko K. E. , Driga M. B. , Kiselev A. V. , Russkikh I. V. , Obolkin V. A. , Shikhovtsev M. Yu.
Published: May 2023

The present study is aimed at the development of a novel empirical base for application to ground-based astronomical telescopes. A Weather Research and Forecasting (WRF) model is used for description of atmospheric flow structure with a high spatial resolution within the Baikal Astrophysical Observatory (BAO) region. Mesoscale vortex structures are found within the atmospheric boundary layer, which affect the quality of astronomical images. The results of simulations show that upward air motions in the lower atmosphere are suppressed both above the cold surface of Lake Baikal and inside mesoscale eddy structures. A model of the outer scale of turbulence for BAO is developed. In this work, we consider the seeing parameter that represents the full width at half-maximum of the point spread function. Optical turbulence profiles are obtained and daytime variations of seeing are estimated. Vertical profiles of optical turbulence are optimized taking into account data from direct optical observations of solar images.
Characteristics and Mechanisms of Debris Bed Formation Behavior in Severe Accidents of Sodium-Cooled Fast Reactors: Experimental and Modeling Studies
Authors: Xu Ruicong , Cheng Songbai
Published: May 2023

A Sodium-cooled Fast Reactor (SFR) is one of the optimized candidates in Generation IV nuclear reactor systems, but safety is an essential issue for SFR development and application. Most knowledge was accumulated through SFR safety investigations, especially for Core Disruptive Accidents (CDAs). During the CDA of SFRs, the molten materials in the core region are likely to discharge into subcooled sodium and form a debris bed on the lower region of the reactor vessel. Noticing that elaboration on the characteristics and mechanisms of Debris Bed Formation (DBF) behavior should be essential for the subsequent analysis of debris bed coolability and accident progression through various experimental and modeling studies, much knowledge was obtained during the past decades. Motivated to promote future investigations on CDAs of SFRs, the previous experiments and modeling studies on DBF behavior are systematically reviewed and discussed in this paper. The experimental results showed that the flow-regime and accumulated-bed characteristics during DBF were influenced by varying parameters and realistic conditions. Through the modeling studies, several empirical models were proposed for predicting the flow regime and accumulated-bed characteristics in DBF. In addition, to promote further development of research, the future prospects concerning DBF behavior are also described.
Shadow Effect of Human Obstacles on Indoor Visible Light Communication System with Multiple Light Sources
Authors: Zhang Ying , Cai Ouyang , Yang Yufeng
Published: May 2023

When the direct visible-light channel is affected by people walking or other obstacles, the shadow effect formed in the receiver space affects communication performance and can even lead to communication interruption. In this paper, two numerical methods for calculating the shadow area of the human body were proposed for an indoor multi-light communication system. The influence of shadows on system performance was analyzed using the mean square errors of illuminance and signal-to-noise ratio, as well as the interrupt probability, as parameters. The results showed that shadows had a great influence on the performance of the visible-light communication system. When the number of light sources was fixed, the shadow effect could be effectively reduced by optimizing the layout of the light sources. These research results can provide a theoretical basis for improving the stability of visible-light communication systems.
Angle-Regulating Rule of Guide Vanes of Variable Geometry Turbine Adjusting Mechanism
Authors: Zhong Yan , Chen Liangyu , Wang Xinyu , Zhao Lei , Bai Haoxi , Han Bing , Cheng Shengzhen , Luo Jingbo
Published: May 2023

In recent years, more and more attention has been paid to research on variable geometry turbine engines with the increasing requirement of engine performance. Variable geometry turbine technology can significantly improve the operating performance of aero engines. Adjusting the working angle of the turbine guide vane can change the thermodynamic cycle of the engine operation, so that the turbine can respond to different engine operating conditions. Variable geometry turbines work in harsh environments. Therefore, the design of the variable geometry turbine needs to consider the effect of thermal deformations of the mechanism on operational stability. There are few research studies on variable geometry turbine adjusting mechanisms. This paper established the numerical calculation models of two adjusting mechanisms by integrating fluid mechanics, heat transfer, and dynamic theories, which are paddle and push–pull rod mechanisms. The models were applied to study the effects of components’ thermal deformations and flexible bodies on the motion characteristics of the adjusting mechanism. Furthermore, the performance of the two adjusting mechanisms was compared. The calculation results show that the paddle rod adjusting mechanism can accurately adjust the angles of guide vanes. The paddle rod adjusting mechanism has a larger driving stroke and smaller driving force than the push–pull rod adjusting mechanism. The paddle adjustment mechanism was better suited to the operational requirements of the variable geometry turbine. The research results of this paper are relevant to the design of variable geometry turbine regulation structures.
The Test–Retest Reproducibility, Standard Error Measurement, and Smallest Real Difference of Dynamic Balance Tests in Chronic Stroke Survivors
Authors: Lee Kyeongbong , Lee GyuChang
Published: May 2023

Background: A dynamic balance assessment of stroke patients is a very important factor in their rehabilitation process. The aim of this study was to investigate the test–retest reproducibility and smallest real differences in the dynamic balance tests of chronic stroke survivors. Methods: This was a methodological study that fifty-three chronic stroke survivors participated in. Dynamic balance tests were performed using the figure of eight walk test, four square step test, and step test. These tests and measurements were performed twice with 1-week intervals and intra-class correlation coefficients (ICC) were used to investigate their test–retest reliability. To determine the size of the measurement error, the standard error of measurement (SEM) and smallest real difference (SRD) were used. The SEM was used to compare the test–retest reproducibility. Results: The test–retest reliability of the figure of eight walk test, four square step test, and step test was confirmed to be high, with an ICC = 0.93~0.99. The SEMs were 2.21 and 2.25 for the figure of eight walk test and four-square step test, respectively. As for the step test (paretic and non-paretic side), the SEMs were 0.68 and 0.70, respectively, which were <10% of the average score. The SRDs of the figure of eight walk test, four square step test, and step test (paretic and non-paretic side) were 6.10, 6.21, and 1.87 and 1.93, respectively. This showed a reliability of <20% of the highest score. The SRDs (%) of the figure of eight walk test, four square step test, and step test (paretic and non-paretic sides) were 28.9%, 21.9%, and 27.32% and 24.43%, respectively. The SEM for all the tests was <30% and the level of measurement error was acceptable. The ICCs of the test–retest reliability of the figure of eight walk test, four square step test, and step test were identified as high, and the test–retest reproducibility was verified by the low values of the SEM and SRD. Conclusions: The figure of eight walk test, four square step test, and step test might be useful tools for clinicians to examine the changes in dynamic balance over time in the rehabilitation of chronic stroke survivors.
Contactless Palm Vein Recognition Based on Attention-Gated Residual U-Net and ECA-ResNet
Authors: Htet Aung Si Min , Lee Hyo Jong
Published: May 2023

Palm vein recognition has received some considerable attention regarding its use in biometric identification. Palm vein characteristics offer a superior level of security and reliability in personal identification compared to extrinsic methods such as fingerprint, face, and palm print recognition, as vein patterns are difficult to duplicate and do not change throughout one’s lifetime. This study proposes both segmentation and recognition methods to enhance the authentication performance and achieve correct identification using palm vein features. First, we propose a segmentation model based on the U-Net model, enhanced with an attention gate, to effectively segment palm vein patterns. The incorporation of both the attention gate and residual block allows the segmentation model for the learning of the essential features required for specific segmentation tasks. The Hessian-based Jerman filtering method is used for ground-truth labeling. The segmentation model extracts the palm vein patterns and filters out the irrelevant and noisy pixels for the purpose of recognition. The efficient channel attention residual network is trained to learn discriminative features for personal identification using combined margin-based loss functions for palm vein recognition. The channel attention module enhances the useful information and suppresses irrelevant features in the feature maps, which overcomes the problem of rotation, position translation, and scale transformation, as well as improves the recognition rate. The combined loss function used in this study increases the similarity between the intra-class samples and the diversity between inter-class samples. The proposed recognition model achieved 100% accuracy for palm vein recognition and an equal error rate of 0.018 for palm vein verification.
Special Issue on Frontiers in Hybrid Vehicles Powertrain
Authors: Cammalleri Marco , Di Dio Vincenzo , Castellano Antonella
Published: May 2023

The urgent need to reduce greenhouse gases and toxic emissions is fostering a rapid shift towards more sustainable transport [...]
Applicability of the Effective Index Method for the Simulation of X-Cut LiNbO3 Waveguides
Authors: Moskalev Dmitrii , Kozlov Andrei , Salgaeva Uliana , Krishtop Victor , Volyntsev Anatolii
Published: May 2023

Photonic integrated circuits (PIC) find applications in the fields of microwaves, telecoms and sensing. Generally, PICs are fabricated on a base of isotropic materials such as SOI, Si3N4, etc. However, for some applications, anisotropic substrates such as LiNbO3 are used. A thin film of LiNbO3 on an insulator (LNOI) is a promising material platform for complex high-speed PICs. The design and simulation of PICs on anisotropic materials should be performed using rigorous numerical methods based on Maxwell’s equations. These methods are characterized by long calculation times for one simulation iteration. Since a large number of simulation iterations are performed during the PIC design, simulation methods based on approximations should be used. The effective index method (EIM) is an approximation-based method and is widely applied for simulations of isotropic waveguides. In this study, the applicability of EIM for simulations of anisotropic waveguides is analyzed. The results obtained by EIM are compared with the calculation results of a rigorous finite-difference frequency-domain (FDFD) method for evaluation of the EIM’s applicability limits. In addition, radiation losses in waveguides with rough sidewalls are estimated using the Payne–Lacey model and EIM. The results demonstrate the applicability of EIM for the simulation of anisotropic LNOI-based waveguides with cross-section parameters specified in this paper.
Interdiffusion in Zr-Mo/W Intermetallics
Authors: Wang Kaihua , Liu Xingwei , Liu Tianyu , He Chuan , Liu Jinxu
Published: May 2023

Intermetallic compounds or solid solutions can form between Zr and Mo/W, in which the multiphase of the diffusion may be influenced by each other. Interdiffusion kinetic data in such intermetallic systems are highly demanded for material design. In this work, solid–solid diffusion couples of Zr-Mo and Zr-W were prepared by the fixture method, and the interdiffusion behaviors of Zr-Mo and Zr-W at 1300–1500 °C were systematically investigated. The results showed that the intermetallic compounds Mo2Zr/W2Zr formed in the Zr-Mo/W diffusion systems. The growth constants of the Mo2Zr and W2Zr phases varied with temperature in accordance with the Arrhenius relationship, and the activation energies of growth were 109 kJ/mol and 285 kJ/mol, respectively. In addition, (Zr, Mo) solid solution formed between Mo2Zr and pure Zr as diffusion proceeded, resulting in a lower chemical potential for the formation of Mo2Zr. The den Broeder method was used in calculating the interdiffusion coefficients of the solid solution. The results showed that the interdiffusion coefficient in the (Zr, Mo) solid solution decreased with the increase of Mo concentration. Moreover, the diffusion activation energy of the solid solution was evaluated based on the Arrhenius relationship, and the activation energy was 145–170 kJ/mol when the Mo content was in the range of 2–10 at. %. These diffusion kinetic data provide a reference for the composition design and preparation technic of Zr-based alloys.
RNA Modification Related Diseases and Sensing Methods
Authors: Ohkawa Mayuka , Konno Masamitsu
Published: May 2023

Epitranscriptomics is the study of RNA base modifications, including functionally relevant transcriptomic changes. Epitranscriptomics has been actively studied in recent years and has been reported to play important roles in development, homeostasis, the immune system, and various life phenomena such as cancer, neurological diseases, and infectious diseases. However, a major problem is the development of sequencing methods to map RNA base modifications throughout the transcriptome. In recent years, various methods for RNA base modification have been actively studied, and we are beginning to successfully measure base modifications that have been difficult to measure in previous years. In this review, we will discuss in detail the biological significance of RNA modifications and the latest techniques for detecting RNA modifications.
Characterization of Flexor Digitorum Superficialis Muscle Stiffness Using Ultrasound Shear Wave Elastography and MyotonPRO: A Cross-Sectional Study Investigating the Correlation between Different Approaches
Authors: Tantipoon Phongpan , Praditpod Nuttaporn , Pakleppa Markus , Li Chunhui , Huang Zhihong
Published: May 2023

Muscle stiffness provides a key insight toward clinical assessment for rehabilitation. Regarding the high-cost and technical skill requirement of ultrasound shear wave elastography (SWE) restricting extensive clinical use, MyotonPRO has been proposed as a complementary tool for muscle stiffness measurement. There is a deficiency of studies revealing the use of this tool for measuring muscle stiffness contributing to hand control. The purpose of this study was to assess the capability and effectiveness of MyotonPRO and SWE for hand muscle stiffness characterization. The stiffness of the dominant flexor digitorum superficialis (FDS) muscle of 25 healthy participants (12 males and 13 females) aged 29.60 ± 9.81 years was evaluated while they performed grip tasks. The muscle stiffness of males and females was compared. The correlation between dynamic muscle stiffness given by MyotonPRO and Young’s modulus obtained from SWE was investigated. Statistical analysis indicated a significant difference in the dynamic muscle stiffness between genders in all conditions (p < 0.05), whereas a significant difference in Young’s modulus was found only at the resting state. A moderate correlation was found between dynamic muscle stiffness and Young’s modulus (r ranged from 0.243 to 0.489). Therefore, MyotonPRO can be used to assess the muscle stiffness of the FDS muscle at rest and during muscle contraction.
Review of Jackson Herring’s Early Work on Thermal Convection
Authors: Kerr Robert M.
Published: May 2023

Jack Herring had three mid-1960s numerical papers on Rayleigh-Bénard thermal convection that might seem primitive by today’s standards, but already encapsulated many of the questions that are still being asked. All of them use severely truncated versions of the incompressible Navier–Stokes–Boussinesq equations with only one, or just a few, horizontal Fourier modes. In the first two papers, 1963 and 1964, the presented results used only one Fourier mode α and three variables. The single mode’s variables are its vertical velocity profile wα(z,t), its temperature profile θα(z,t) and the horizontally uniform vertical profile of the background temperature ψ(z,t). All of the second- and third-order terms are ignored except the convective heat flux wθ¯. The objective was to find asymptotic steady-state solutions. Each paper found evidence for the one-third Nusselt versus Rayleigh scaling of Nu∼Ra1/3, originally derived from Malkus’ maximum flux principle. The 1963 paper uses free-slip upper and lower boundaries, with magnitudes of Nu that are a factor of three larger than the experiments. In the 1964 paper, by introducing no-slip/rigid boundary conditions, the magnitude of Nu dropped to within 20% of the experimental values. Both Nu(Ra) relations are in good agreement with circa-1990 direct numerical simulations (DNS). This dependence upon the boundary condition at the walls suggests that to obtain physically realistic scaling, no-slip boundary conditions are necessary. The third paper is discussed only in terms of what it might have been aiming to accomplish and its relation to the earlier free-slip results.
Individual and Combined Effects of 3D Buildings and Green Spaces on the Urban Thermal Environment: A Case Study in Jinan, China
Authors: Wang Jiayun , Meng Fei , Lu Huanhuan , Lv Yongqiang , Jing Tingting
Published: May 2023

This study aimed to accurately grasp the impact mechanism and change rule of buildings and green spaces on land surface temperature (LST), which is of great significance for alleviating urban heat islands (UHIs) and formulating adaptation measures. Taking Jinan, China, as the study area, combined multisource remote sensing data were used in this study to construct an index system of the influencing factors. We used a spatial regression model to explore the relative contribution of the influencing indicators on LST. We also drew a marginal utility curve to quantify the heating/cooling effect of the leading indicators. The results showed that, firstly, among the 3D building indicators, the leading indicators affecting LST were the degree of spatial convergence (SCD) and the building surface area (BSA). Among the green space indicators, the largest patch index (LPI), green coverage rate (GCR), and edge density (ED) were significantly negatively correlated with LST. Secondly, when we considered the 15 indicators comprehensively, SCD was the most influential indicator, with a contribution of 24.7%, and the contribution of the green space indicators to LST was significantly reduced. Thirdly, among the leading indicators, SCD was positively correlated with LST. When SCD was less than 60%, LST increased by about 0.38 °C for every 10% increase. When GCR > 44%, LST was significantly reduced, and when GCR > 62%, a cooling effect of 1.1 °C was observed. Beyond this threshold, the cooling effect will not improve significantly. This study shows that when 3D buildings are densely distributed and crowded, the cooling effect of green space will be limited to some extent by 3D buildings. The key to mitigating UHIs is to rationally configure and optimize the spatial structure of 3D buildings.
Wave and Meso-Scale Eddy Climate in the Arctic Ocean
Authors: Xing Guojing , Shen Wei , Wei Meng , Li Huan , Shao Weizeng
Published: May 2023

Under global climate change, the characteristics of oceanic dynamics are gradually beginning to change due to melting sea ice. This study focused on inter-annual variation in waves and mesoscale eddies (radius > 40 km) in the Arctic Ocean from 1993 to 2021. The waves were simulated by a numerical wave model, WAVEWATCH-III (WW3), which included a parameterization of ice–wave interaction. The long-term wind data were from the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis (ERA-5), and current and sea level data from the HYbrid Coordinate Ocean Model (HYCOM)were used as the forcing fields. The simulated significant wave heights (SWHs) were validated against the 2012 measurements from the Jason-2 altimeter, yielding a 0.55 m root mean square error (RMSE) with a 0.95 correlation (COR). The seasonal variation in WW3-simulated SWH from 2021 to 2022 showed that the SWH was the lowest in summer (July and August 2021) and highest in winter (November 2021 to April 2022). This result indicates that parts of the Arctic could become navigable in summer. The mesoscale eddies were identified using a daily-averaged sea level anomalies (SLA) product with a spatial resolution of a 0.25° grid for 1993−2021. We found that the activity intensity (EKE) and radius of mesoscale eddies in the spatial distribution behaved in opposing ways. The analysis of seasonal variation showed that the increase in eddy activity could lead to wave growth. The amplitude of SWH peaks was reduced when the Arctic Oscillation Index (AOI) was <−1.0 and increased when the AOI was >0.5, especially in the case of swells. The amplitude of SWH oscillation was low, and the EKE and radius of eddies were relatively small. Although the radius and EKE of eddies were almost similar to the AOI, the waves also influenced the eddies.
On 3-Restricted Edge Connectivity of Replacement Product Graphs
Authors: Cui Yilan , Ou Jianping , Liu Saihua
Published: May 2023

A 3-restricted edge cut is an edge cut of a connected graph that separates this graph into components, each having an order of at least 3. The minimum size of all 3-restricted edge cuts of a graph is called its 3-restricted edge connectivity. This work determines the upper and lower bounds on the 3-restricted edge connectivity of replacement product graphs and presents sufficient conditions for replacement product graphs to be maximally 3-restricted edge connected. As a result, the 3-restricted edge connectivity of replacement product graphs of some special graphs are determined.
An Approximation Algorithm for a Variant of Dominating Set Problem
Authors: Wang Limin , Wang Wenqi
Published: May 2023

In this paper, we consider a variant of dominating set problem, i.e., the total dominating set problem. Given an undirected graph G=(V,E), a subset of vertices T⊆V is called a total dominating set if every vertex in V is adjacent to at least one vertex in T. Based on LP relaxation techniques, this paper gives a distributed approximation algorithm for the total dominating set problem in general graphs. The presented algorithm obtains a fractional total dominating set that is, at most, k(1+Δ1k)Δ1k times the size of the optimal solution to this problem, where k is a positive integer and Δ is the maximum degree of G. The running time of this algorithm is constant communication rounds under the assumption of a synchronous communication model.
Population Status of a Regionally Endangered Plant, Lunaria rediviva (Brassicaceae), near the Eastern Border of Its Range
Authors: Khapugin Anatoliy A. , Chugunov Gennadiy G.
Published: May 2023

Long-term studies of plant populations provide valuable knowledge on the influence of various environmental factors on plant species. The status of edge-range species populations is especially important to be studied due to their higher vulnerability to extinction. This paper aimed to study the Lunaria rediviva population at the eastern border of its range (National Park “Smolny”, Republic of Mordovia, Russia). The study was carried out in 2013–2018. Assessment of the L. rediviva population was performed on the basis of individual parameters of plants (height of the individual, number of leaves per individual, number of inflorescences, flowers, fruits per one generative individual, and the fruit set), and density of individuals. Ontogenetic structure of the population was identified by distinguishing juvenile, mature vegetative, and reproductive individuals. The relationships between weather conditions (mean values of temperature, air moisture, wind strength, precipitation divided to three decades per month) and population parameters of L. rediviva were identified. Results showed changes in the ontogenetic structure of the population. The type of its population changed from vegetatively oriented to bimodal, with a decrease (R2 = 0.686) in the proportion of mature vegetative individuals. We demonstrated a significant decline in some parameters of the L. rediviva reproduction. We found a significant negative correlation between the fruit set and the moisture at mid-July (r = −0.84, p < 0.05), and wind strength in late May (r = −0.83, p < 0.05) and early June (r = −0.83, p < 0.05). It was found that the number of both flowers and fruits per individual is significantly positively correlated with the precipitation in late April, and they negatively correlated with these parameters and the temperature in late July. We assume that the habitat shading negatively influences the L. rediviva population status.
Bcl-xL Is Spontaneously Inserted into Preassembled Nanodiscs and Stimulates Bax Insertion in a Cell-Free Protein Synthesis System
Authors: Rouchidane Eyitayo Akandé , Boudier-Lemosquet Axel , Chaignepain Stéphane , Priault Muriel , Manon Stéphen
Published: May 2023

The antiapoptotic protein Bcl-xL is a major regulator of cell death and survival, but many aspects of its functions remain elusive. It is mostly localized in the mitochondrial outer membrane (MOM) owing to its C-terminal hydrophobic α-helix. In order to gain further information about its membrane organization, we set up a model system combining cell-free protein synthesis and nanodisc insertion. We found that, contrary to its proapoptotic partner Bax, neosynthesized Bcl-xL was spontaneously inserted into nanodiscs. The deletion of the C-terminal α-helix of Bcl-xL prevented nanodisc insertion. We also found that nanodisc insertion protected Bcl-xL against the proteolysis of the 13 C-terminal residues that occurs during expression of Bcl-xL as a soluble protein in E. coli. Interestingly, we observed that Bcl-xL increased the insertion of Bax into nanodiscs, in a similar way to that which occurs in mitochondria. Cell-free synthesis in the presence of nanodiscs is, thus, a suitable model system to study the molecular aspects of the interaction between Bcl-xL and Bax during their membrane insertion.
Uncovering the Underlying Mechanisms Blocking Replication of Bluetongue Virus Serotype 26 (BTV-26) in Culicoides Cells
Authors: Monsion Baptiste , Mohd Jaafar Fauziah , Mertens Peter P. C. , Attoui Houssam
Published: May 2023

At least 12 serotypes of ‘atypical’ bluetongue virus (BTV-25 to BTV-36) have been identified to date. These atypical serotypes fail to infect/replicate in Culicoides-derived cell lines and/or adult Culicoides vectors and hence can no longer be transmitted by these vectors. They appear to be horizontally transmitted from infected to in-contact ruminants, although the route(s) of infection remain to be identified. Viral genome segments 1, 2 and 3 (Seg-1, Seg2 and Seg-3) of BTV-26 were identified as involved in blocking virus replication in KC cells. We have developed Culicoides-specific expression plasmids, which we used in transfected insect cells to assess the stability of viral mRNAs and protein expression from full-length open reading frames of Seg-1, -2 and -3 of BTV-1 (a Culicoides-vectored BTV) or BTV-26. Our results indicate that the blocked replication of BTV-26 in KC cells is not due to an RNAi response, which would lead to rapid degradation of viral mRNAs. A combination of degradation/poor expression and/or modification of the proteins encoded by these segments appears to drive the failure of BTV-26 core/whole virus-particles to assemble and replicate effectively in Culicoides cells.
Functional Expression of IP, 5-HT4, D1, A2A, and VIP Receptors in Human Odontoblast Cell Line
Authors: Kitayama Eri , Kimura Maki , Ouchi Takehito , Furusawa Masahiro , Shibukawa Yoshiyuki
Published: May 2023

Odontoblasts are involved in sensory generation as sensory receptor cells and in dentin formation. We previously reported that an increase in intracellular cAMP levels by cannabinoid 1 receptor activation induces Ca2+ influx via transient receptor potential vanilloid subfamily member 1 channels in odontoblasts, indicating that intracellular cAMP/Ca2+ signal coupling is involved in dentinal pain generation and reactionary dentin formation. Here, intracellular cAMP dynamics in cultured human odontoblasts were investigated to understand the detailed expression patterns of the intracellular cAMP signaling pathway activated by the Gs protein-coupled receptor and to clarify its role in cellular functions. The presence of plasma membrane Gαs as well as prostaglandin I2 (IP), 5-hydroxytryptamine 5-HT4 (5-HT4), dopamine D1 (D1), adenosine A2A (A2A), and vasoactive intestinal polypeptide (VIP) receptor immunoreactivity was observed in human odontoblasts. In the presence of extracellular Ca2+, the application of agonists for the IP (beraprost), 5-HT4 (BIMU8), D1 (SKF83959), A2A (PSB0777), and VIP (VIP) receptors increased intracellular cAMP levels. This increase in cAMP levels was inhibited by the application of the adenylyl cyclase (AC) inhibitor SQ22536 and each receptor antagonist, dose-dependently. These results suggested that odontoblasts express Gs protein-coupled IP, 5-HT4, D1, A2A, and VIP receptors. In addition, activation of these receptors increased intracellular cAMP levels by activating AC in odontoblasts.
Relationship between Diabetic Nephropathy and Development of Diabetic Macular Edema in Addition to Diabetic Retinopathy
Authors: Suzuki Yukihisa , Kiyosawa Motohiro
Published: May 2023

This study aimed to examine the relationship between diabetic retinopathy (DR) and systemic factors. We evaluated 261 patients (143 men, 118 women, aged 70.1 ± 10.1 years) with type 2 diabetes. All participants underwent a fundus examination, fundus photography using spectral domain optical coherence tomography (SD-OCT), and blood tests. For glycated hemoglobin (HbA1c) levels, the average and highest values in the past were used. We observed DR in 127 (70 men and 57 women) of 261 patients. Logistic regression analyses revealed a significant correlation between DR development and the duration of diabetes (OR = 2.40; 95% CI: 1.50), average HbA1c level (OR = 5.57; 95% CI: 1.27, 24.4), highest HbA1c level (OR = 2.46; 95% CI: 1.12, 5.38), and grade of diabetic nephropathy (DN) (OR = 6.23; 95% CI: 2.70, 14.4). Regression analyses revealed a significant correlation between the severity of DR and duration of diabetes (t = –6.66; 95% CI: 0.21, 0.39), average HbA1c level (t = 2.59; 95% CI: 0.14, 1.02), and severity of DN (t = 6.10; 95% CI: 0.49, 0.97). Logistic regression analyses revealed a significant correlation between diabetic macular edema (DME) development and DN grade (OR = 2.22; 95% CI: 1.33, 3.69). DN grade correlates with the development of DR and DME, and decreased renal function predicts the onset of DR.
Metal-Multilayered Nanomechanical Cantilever Sensor for Detection of Molecular Adsorption
Authors: Toda Masaya , Ono Takahito , Okubo Jun
Published: May 2023

A metal-multilayered nanomechanical cantilever sensor was proposed to reduce the temperature effect for highly sensitive gas molecular detection. The multilayer structure of the sensor reduces the bimetallic effect, allowing for the detection of differences in molecular adsorption properties on various metal surfaces with higher sensitivity. Our results indicate that the sensor exhibits higher sensitivity to molecules with greater polarity under mixed conditions with nitrogen gas. We demonstrate that stress changes caused by differences in molecular adsorption on different metal surfaces can be detected and that this approach could be used to develop a gas sensor with selectivity for specific gas species.
Analysis of Risk Factors for White Matter Hyperintensity in Older Adults without Stroke
Authors: Zheng Kai , Wang Zheng , Chen Xi , Chen Jiajie , Fu Yu , Chen Qin
Published: May 2023

Background: White matter hyperintensity (WMH) is prevalent in older adults aged 60 and above. A large proportion of people with WMH have not experienced stroke and little has been reported in the literature. Methods: The case data of patients aged ≥60 years without stroke in Wuhan Tongji Hospital from January 2015 to December 2019 were retrospectively analyzed. It was a cross-sectional study. Univariate analysis and logistic regression were used to analyze independent risk factors for WMH. The severity of WMH was assessed using the Fazekas scores. The participants with WMH were divided into periventricular white matter hyperintensity (PWMH) group and deep white matter hyperintensity (DWMH) group, then the risk factors of WMH severity were explored separately. Results: Eventually, 655 patients were included; among the patients, 574 (87.6%) were diagnosed with WMH. Binary logistic regression showed that age and hypertension were associated with the prevalence of WMH. Ordinal logistic regression showed that age, homocysteine, and proteinuria were associated with the severity of WMH. Age and proteinuria were associated with the severity of PWMH. Age and proteinuria were associated with the severity of DWMH. Conclusions: The present study showed that in patients aged ≥60 years without stroke, age and hypertension were independent risk factors for the prevalence of WMH; while the increasing of age, homocysteine, and proteinuria were associated with greater WMH burden.
Transfusion with Blood Plasma from Young Mice Affects rTg4510 Transgenic Tau Mice Modeling of Alzheimer’s Disease
Authors: Hernandez Carlos M. , Barkey Rachel E. , Craven Kristen M. , Pedemonte Karin A. , Alisantosa Bernadette , Sanchez Jonathan O. , Flinn Jane M.
Published: May 2023

Alzheimer’s disease (AD) is characterized by the buildup of plaques and tangles in the brain. Tangles are formed when the stabilizing protein, tau, becomes hyperphosphorylated and clumps together. There are limited treatments for AD; therefore, the exploration of new treatments is warranted. Previous research showed that plasma transfusion from young donor mice improved spatial memory and increased synaptic proteins in old transgenic APP/PS1 mice, suggesting a remediation of memory and synaptic function. In the current study, plasma was transfused from 2–3-month-old young wildtype mice (WT) to 8-month-old rTg4510 mice expressing human tau (Tau). One week after the transfusions, behavior and tau pathology were examined. We found that Tau mice injected with plasma had lower expression of phosphorylated tau (ptau) in the brain, accompanied by fewer tau tangles in the cortex and CA1 region of the hippocampus and smaller tau tangles in the cortex, when compared to Tau mice injected with saline. Despite no improvement in behavior, the decreased level of ptau and tangles open the door to future studies involving plasma transfusions.
Brain Health Indicators Following Acute Neuro-Exergaming: Biomarker and Cognition in Mild Cognitive Impairment (MCI) after Pedal-n-Play (iPACES)
Authors: Nath Kartik , Ferguson IreLee , Puleio Alexa , Wall Kathryn , Stark Jessica , Clark Sean , Story Craig , Cohen Brian , Anderson-Hanley Cay
Published: May 2023

Facing an unrelenting rise in dementia cases worldwide, researchers are exploring non-pharmacological ways to ameliorate cognitive decline in later life. Twenty older adults completed assessments before and after a single bout of interactive physical and cognitive exercise, by playing a neuro-exergame that required pedaling and steering to control progress in a tablet-based video game tailored to impact executive function (the interactive Physical and Cognitive Exercise System; iPACES v2). This study explored the cognitive and biomarker outcomes for participants with mild cognitive impairment (MCI) and normative older adults after 20 min of pedal-to-play exercise. Neuropsychological and salivary assessments were performed pre- and post-exercise to assess the impact. Repeated-measures ANOVAs revealed significant interaction effects, with MCI participants experiencing greater changes in executive function and alpha-amylase levels than normative older adults; within-group changes were also significant. This study provides further data regarding cognitive effects and potential mechanisms of action for exercise as an intervention for MCI.
Towards a Neurophenomenological Understanding of Self-Disorder in Schizophrenia Spectrum Disorders: A Systematic Review and Synthesis of Anatomical, Physiological, and Neurocognitive Findings
Authors: Martin James C. , Clark Scott R. , Schubert K. Oliver
Published: May 2023

The concept of anomalous self-experience, also termed Self-Disorder, has attracted both clinical and research interest, as empirical studies suggest such experiences specifically aggregate in and are a core feature of schizophrenia spectrum disorders. A comprehensive neurophenomenological understanding of Self-Disorder may improve diagnostic and therapeutic practice. This systematic review aims to evaluate anatomical, physiological, and neurocognitive correlates of Self-Disorder (SD), considered a core feature of Schizophrenia Spectrum Disorders (SSDs), towards developing a neurophenomenological understanding. A search of the PubMed database retrieved 285 articles, which were evaluated for inclusion using PRISMA guidelines. Non-experimental studies, studies with no validated measure of Self-Disorder, or those with no physiological variable were excluded. In total, 21 articles were included in the review. Findings may be interpreted in the context of triple-network theory and support a core dysfunction of signal integration within two anatomical components of the Salience Network (SN), the anterior insula and dorsal anterior cingulate cortex, which may mediate connectivity across both the Default Mode Network (DMN) and Fronto-Parietal Network (FPN). We propose a theoretical Triple-Network Model of Self-Disorder characterized by increased connectivity between the Salience Network (SN) and the DMN, increased connectivity between the SN and FPN, decreased connectivity between the DMN and FPN, and increased connectivity within both the DMN and FPN. We go on to describe translational opportunities for clinical practice and provide suggestions for future research.
The Importance of Measuring Mental Wellbeing in the Context of Psychological Distress: Using a Theoretical Framework to Test the Dual-Continua Model of Mental Health
Authors: Mason Stephens Jackson , Iasiello Matthew , Ali Kathina , van Agteren Joep , Fassnacht Daniel B.
Published: May 2023

The dual-continua model of mental health suggests that psychological distress and mental wellbeing operate on two distinct yet related continua, both uniquely contributing to overall mental health. Previous literature provides support for the dual-continua model; however, inconsistent methodologies lacking a common theoretical underpinning have led to findings that are difficult to compare across studies. Using archival data, this study aimed to test the following three theoretically derived criteria proposed to accurately examine the dual-continua model: (1) confirming independent existence, (2) disconfirming bipolarity, and (3) quantifying functional independence. Method: In total, 2065 participants (female n = 1193; 57.8%) completed two online assessments (minimum 30 days apart) measuring psychological distress, mental wellbeing, and demographic information. Results: In total, 1.1% of participants experienced high distress as well as mental wellbeing confirming that psychological distress and mental wellbeing exist independently (Criterion 1). Bipolarity (Criterion 2) was partly disconfirmed: mental wellbeing consistently decreased as symptom severity increased for depression; however, anxiety and stress did not meet bipolarity requirements. Functional independence (Criterion 3) was established: longitudinal analysis found that participants reliably and simultaneously increased (2.7%) or decreased (4.2%) in distress and mental wellbeing, while cross-sectional analysis showed that psychological distress only explained 38% of the variance in mental wellbeing. Discussion: Findings provide further support for the dual-continua model through analysis of the proposed assessment criteria, suggesting a further need to measure the dual-continua model at the subdomain level, e.g., depression, anxiety, and stress, as opposed to global psychological distress. Validation for the proposed assessment criteria provides important methodological foundations for future studies.