bluuebunny/crossref_metadata_2025 huggingface dataset:
Sperm Abnormality Detection Using Sequential Deep Neural Network
Authors: Shahzad Suleman , Ilyas Muhammad , Lali M. Ikram Ullah , Rauf Hafiz Tayyab , Kadry Seifedine , Nasr Emad Abouel
Published: January 2023

Sperm morphological analysis (SMA) is an essential step in diagnosing male infertility. Using images of human sperm cells, this research proposes a unique sequential deep-learning method to detect abnormalities in semen samples. The proposed technique identifies and examines several components of human sperm. In order to conduct this study, we used the online Modified Human Sperm Morphology Analysis (MHSMA) dataset containing 1540 sperm images collected from 235 infertile individuals. For research purposes, this dataset is freely available online. To identify morphological abnormalities in different parts of human sperm, such as the head, vacuole, and acrosome, we proposed sequential deep neural network (SDNN) architecture. This technique is also particularly effective with low-resolution, unstained images. Sequential deep neural networks (SDNNs) demonstrate high accuracy in diagnosing morphological abnormalities based on the given dataset in our tests on the benchmark. Our proposed algorithm successfully detected abnormalities in the acrosome, head, and vacuole with an accuracy of 89%, 90%, and 92%, respectively. It is noteworthy that our system detects abnormalities of the acrosome and head with greater accuracy than current state-of-the-art approaches on the suggested benchmark. On a low-specification computer/laptop, our algorithm also requires less execution time. Additionally, it can classify photos in real time. Based on the results of our study, an embryologist can quickly decide whether to use the given sperm.
Poisson Doubly Warped Product Manifolds
Authors: Al-Dayel Ibrahim , Aloui Foued , Deshmukh Sharief
Published: January 2023

This article generalizes some geometric structures on warped product manifolds equipped with a Poisson structure to doubly warped products of pseudo-Riemannian manifolds equipped with a doubly warped Poisson structure. First, we introduce the notion of Poisson doubly warped product manifold (fB×bF,Π=μvΠBh+νhΠFv,g) and express the Levi-Civita contravariant connection, curvature and metacurvature of (fB×bF,Π,g) in terms of Levi-Civita connections, curvatures and metacurvatures of components (B,ΠB,gB) and (F,ΠF,gF). We also study compatibility conditions related to the Poisson structure Π and the contravariant metric g on fB×bF, so that the compatibility conditions on (B,ΠB,gB) and (F,ΠF,gF) remain consistent in the Poisson doubly warped product manifold (fB×bF,Π,g).
Scale Mixture of Maxwell-Boltzmann Distribution
Authors: Castillo Jaime S. , Gaete Katherine P. , Muñoz Héctor A. , Gallardo Diego I. , Bourguignon Marcelo , Venegas Osvaldo , Gómez Héctor W.
Published: January 2023

This paper presents a new distribution, the product of the mixture between Maxwell-Boltzmann and a particular case of the generalized gamma distributions. The resulting distribution, called the Scale Mixture Maxwell-Boltzmann, presents greater kurtosis than the recently introduced slash Maxwell-Boltzmann distribution. We obtained closed-form expressions for its probability density and cumulative distribution functions. We studied some of its properties and moments, as well as its skewness and kurtosis coefficients. Parameters were estimated by the moments and maximum likelihood methods, via the Expectation-Maximization algorithm for the latter case. A simulation study was performed to illustrate the parameter recovery. The results of an application to a real data set indicate that the new model performs very well in the presence of outliers compared with other alternatives in the literature.
A Forgotten Effects Approach to the Analysis of Complex Economic Systems: Identifying Indirect Effects on Trade Networks
Authors: Chávez-Bustamante Felipe , Mardones-Arias Elliott , Rojas-Mora Julio , Tijmes-Ihl Jaime
Published: January 2023

The purpose of this paper is to identify the emergence of indirect trade flows prompted by the export interaction of the world’s economies. Using data on exports from the United Nations Conference on Trade and Development (UNCTAD) for the period 2016–2021, we construct an international trade network which is analyzed through the “forgotten effects theory” that identifies tuples of countries with an origin, intermediary countries, and a destination. This approach intends to spotlight something beyond the analysis of the direct trade network by the identification of second and third-order paths. The analysis using both network analyses, as well as the forgotten effect approaches, which show that the international trade network presents a hub-and-spoke behavior in contrast to most extant research finding a core-periphery structure. The structure is then comprised of three almost separated trade networks and a hub country that bridges commerce between those networks. The contribution of this article is to move the analysis forward from other works that utilize trade networks, including those of econometric nature—such as the ones based on gravity models—by incorporating indirect relationships between countries, which could provide distinctive and novel insights into the study of economic networks.
Mathematical Modeling of the State of the Battery of Cargo Electric Vehicles
Authors: Martyushev Nikita V. , Malozyomov Boris V. , Sorokova Svetlana N. , Efremenkov Egor A. , Qi Mengxu
Published: January 2023

In this paper, a mathematical simulation model of an electric vehicle traction battery has been developed, in which the battery was studied during the dynamic modes of its charge and discharge for heavy electric vehicles in various driving conditions—the conditions of the urban cycle and movement outside the city. The state of a lithium-ion battery is modeled based on operational factors, including changes in battery temperature. The simulation results will be useful for the implementation of real-time systems that take into account the processes of changing the characteristics of traction batteries. The developed mathematical model can be used in battery management systems to monitor the state of charge and battery degradation using the assessment of the state of charge (SOC) and the state of health (SOH). This is especially important when designing and operating a smart battery management system (BMS) in virtually any application of lithium-ion batteries, providing information on how long the device will run before it needs to be charged (SOC value) and when the battery should be replaced due to loss of battery capacity (SOH value). Based on the battery equivalent circuit and the system of equations, a simulation model was created to calculate the electrical and thermal characteristics. The equivalent circuit includes active and reactive elements, each of which imitates the physicochemical parameter of the battery under study or the structural element of the electrochemical battery. The input signals of the mathematical model are the current and ambient temperatures obtained during the tests of the electric vehicle, and the output signals are voltage, electrolyte temperature and degree of charge. The resulting equations make it possible to assign values of internal resistance to a certain temperature value and a certain value of the degree of charge. As a result of simulation modeling, the dependence of battery heating at various ambient temperatures was determined.
Semi-Automatic 3D Reconstruction of Atheroma Plaques from Intravascular Ultrasound Images Using an ad-hoc Algorithm
Authors: Martínez Javier , Pérez-Palau Daniel , Cilla Myriam , Garrido Neus , Larrañaga Ana , Pérez-Rey Ignacio
Published: January 2023

The occurrence of atheroma plaques in the arteries can eventually obstruct them, leading to diseases such as atherosclerosis, which can cause, among others, a myocardial infarction or a stroke. As a consequence, it is necessary to shorten the time spent in locating and reconstructing the atheroma plaque that can be developed in an artery. This localization is usually conducted manually from the contours located on the cross-sectional radiographs of the artery and then reconstructed by creating the volumes using different techniques. This paper presents a 3-D reconstruction of the atheroma plaque by applying an image processing algorithm ad-hoc developed in order to obtain the boundaries of the atheroma, from a set of intravascular ultrasound images. The advantage of the approach developed in this paper is that it can be implemented in common medical procedures, as an important complementary decision-support tool. By reconstructing the atheroma instead of the artery, this work provides a different approach to improve its location and treatment. Results presented herein can be implemented in machine-learning-based algorithms, able to predict the growth and extent of incipient atheroma plaques, which ultimately contribute to an early detection of this pathology.
Four-Parameter Weibull Distribution with Lower and Upper Limits Applicable in Reliability Studies and Materials Testing
Authors: Kohout Jan
Published: January 2023

A simply curved Weibull plot means that the studied data set has a three-parameter Weibull distribution with a non-zero location parameter representing the lower or the upper limit of the data set. This paper introduces a four-parameter Weibull distribution with both of these limits that can be applied in both reliability and materials engineering. A very reliable indicator of this distribution is the double-curved Weibull plot. The great advantage of this distribution is the fact that the corresponding hazard rate curve can be bathtub-shaped with a great ability to fit the measured data.
Existence and Uniqueness of Generalized and Mixed Finite Element Solutions for Steady Boussinesq Equation
Authors: Luo Zhendong , Liu Xiangdong , Zeng Yihui , Li Yuejie
Published: January 2023

Herein, we mainly employ the fixed point theorem and Lax-Milgram theorem in functional analysis to prove the existence and uniqueness of generalized and mixed finite element (MFE) solutions for two-dimensional steady Boussinesq equation. Thus, we can fill in the gap of research for the steady Boussinesq equation since the existing studies for the equation are assumed the existence and uniqueness of generalized solution without providing proof.
Validation of Multiplex PCR and Serology Detecting Helicobacter Species in Mice
Authors: Butt Julia , Schmitz Mareike , Berkus Bernhard , Schmidt Katja , Höfler Daniela
Published: January 2023

High-throughput multiplexed assays are needed to simplify detection of Helicobacter species in experimental infection and routine health monitoring of laboratory mice. Therefore, fluorescent bead-based hybridization assays for Helicobacter sp. DNA and serology were developed. Multiplex PCR amplicons (H. hepaticus, H. bilis, H. typhlonius, H. pylori, H. muridarum, H. pullorum, H. cinaedi, H. heilmanii, C. jejuni) and antibodies against H. pylori, H. hepaticus, H. bilis were assessed in naturally and experimentally infected mice, and results compared to conventional PCR. Species-specific and sensitive detection of seven Helicobacter spp. <100 copies/PCR, and of two species <1000 copies/PCR was successfully established in the Helicobacter multiplex DNA finder. The novel assay was highly comparable with conventional PCR (kappa = 0.98, 95%CI: 0.94–1.00). Antibody detection of H. hepaticus and H. bilis showed low sensitivity (71% and 62%, respectively) and cross-reactivity in H. typhlonius-infected mice. Infection experiments showed that antibodies develop earliest two weeks after DNA detection in feces. In conclusion, detection of Helicobacter antibodies showed low sensitivity depending on the timing relative to infection. However, Helicobacter multiplex DNA finder is a sensitive and specific high-throughput assay applicable in routine health monitoring for laboratory animals.
Genomic Diversity among Actinomyces naeslundii Strains and Closely Related Species
Authors: Mughal Sadaf Rasheed , Niazi Sadia Ambreen , Do Thuy , Gilbert Steven C. , Didelot Xavier , Radford David R. , Beighton David
Published: January 2023

The aim of this study was to investigate and clarify the ambiguous taxonomy of Actinomyces naeslundii and its closely related species using state-of-the-art high-throughput sequencing techniques, and, furthermore, to determine whether sub-clusters identified within Actinomyces oris and Actinomyces naeslundii in a previous study by multi locus sequence typing (MLST) using concatenation of seven housekeeping genes should either be classified as subspecies or distinct species. The strains in this study were broadly classified under Actinomyces naeslundii group as A. naeslundii genospecies I and genospecies II. Based on MLST data analysis, these were further classified as A. oris and A. naeslundii. The whole genome sequencing of selected strains of A. oris (n = 17) and A. naeslundii (n = 19) was carried out using Illumina Genome Analyzer IIxe and Roche 454 allowing paired-end and single-reads sequencing, respectively. The sequences obtained were aligned using CLC Genomic workbench version 5.1 and annotated using RAST (Rapid Annotation using Subsystem Technology) release version 59 accessible online. Additionally, genomes of seven publicly available strains of Actinomyces (k20, MG1, c505, OT175, OT171, OT170, and A. johnsonii) were also included. Comparative genomic analysis (CGA) using Mauve, Progressive Mauve, gene-by-gene, Core, and Pan Genome, and finally Digital DNA-DNA homology (DDH) analysis was carried out. DDH values were obtained using in silico genome–genome comparison. Evolutionary analysis using ClonalFrame was also undertaken. The mutation and recombination events were compared using chi-square test among A. oris and A. naeslundii isolates (analysis methods are not included in the study). CGA results were consistent with previous traditional classification using MLST. It was found that strains of Actinomyces k20, MG1, c505, and OT175 clustered in A. oris group of isolates, while OT171, OT170, and A. johnsonii appeared as separate branches. Similar clustering to MLST was observed for other isolates. The mutation and recombination events were significantly higher in A. oris than A. naeslundii, highlighting the diversity of A. oris strains in the oral cavity. These findings suggest that A. oris forms six distinct groups, whereas A. naeslundii forms three. The correct designation of isolates will help in the identification of clinical Actinomyces isolates found in dental plaque. Easily accessible online genomic sequence data will also accelerate the investigation of the biochemical characterisation and pathogenesis of this important group of micro-organisms.
In Vitro Assessment of Biofilm Production, Antibacterial Resistance of Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter spp. Obtained from Tonsillar Crypts of Healthy Adults
Authors: Viksne Renata , Racenis Karlis , Broks Renars , Balode Arta Olga , Kise Ligija , Kroica Juta
Published: January 2023

Background and Objective: Tonsillar crypts can be considered a reservoir for a variety of bacterial species. Some bacterial species can be considered part of the normal oropharyngeal microbiota. The roles of other pathogens, for example, the so-called non-oral and respiratory pathogens Staphylococcus aureus, Klebsiella, Pseudomonas, and Acinetobacter spp., which have strong virulence factors, biofilm production capacity, and the ability to initiate infectious diseases, are unclear. The purpose of this study was to detect the presence of S. aureus, K. pneumoniae, P. aeruginosa, and Acinetobacter spp. within the tonsillar crypts of healthy individuals, and to analyze the pathogens’ biofilm production and antibacterial resistances. Results: Only common oropharyngeal microbiota were cultivated from 37 participant samples (40.7%). The most commonly isolated pathogenic bacterium was S. aureus, which was isolated in 41 (45%) participant samples. K. pneumoniae was isolated in seven (7.7%) samples, Acinetobacter spp. were isolated in five (5.5%) samples, and P. aeruginosa was isolated in two (2.2%) samples. Biofilm producers predominated among the pathogenic bacteria; 51 strains were biofilm producers, and among them, 31 strains were moderate or strong biofilm producers. The tested S. aureus, K. pneumoniae, P. aeruginosa, and Acinetobacter spp. strains were sensitive to commonly used antibiotics (amoxicillin–clavulanic acid, clindamycin, or ciprofloxacin). One of the isolated S. aureus strains was MRSA. Conclusions: Biofilm is a commonly observed feature that seems to be a naturally existing form of pathogenic bacteria colonizing human tissue. S. aureus, K. pneumoniae, P. aeruginosa, and Acinetobacter spp. occasionally occur in the tonsillar crypts of healthy individuals, and, therefore, it is most likely that S. aureus, K. pneumoniae, P. aeruginosa, and Acinetobacter spp. in opportunistic tonsillar infections originate from the tonsillar crypt microbiota.
The Cell Wall, Cell Membrane and Virulence Factors of Staphylococcus aureus and Their Role in Antibiotic Resistance
Authors: Nikolic Philip , Mudgil Poonam
Published: January 2023

Antibiotic resistant strains of bacteria are a serious threat to human health. With increasing antibiotic resistance in common human pathogens, fewer antibiotics remain effective against infectious diseases. Staphylococcus aureus is a pathogenic bacterium of particular concern to human health as it has developed resistance to many of the currently used antibiotics leaving very few remaining as effective treatment. Alternatives to conventional antibiotics are needed for treating resistant bacterial infections. A deeper understanding of the cellular characteristics of resistant bacteria beyond well characterized resistance mechanisms can allow for increased ability to properly treat them and to potentially identify targetable changes. This review looks at antibiotic resistance in S aureus in relation to its cellular components, the cell wall, cell membrane and virulence factors. Methicillin resistant S aureus bacteria are resistant to most antibiotics and some strains have even developed resistance to the last resort antibiotics vancomycin and daptomycin. Modifications in cell wall peptidoglycan and teichoic acids are noted in antibiotic resistant bacteria. Alterations in cell membrane lipids affect susceptibility to antibiotics through surface charge, permeability, fluidity, and stability of the bacterial membrane. Virulence factors such as adhesins, toxins and immunomodulators serve versatile pathogenic functions in S aureus. New antimicrobial strategies can target cell membrane lipids and virulence factors including anti-virulence treatment as an adjuvant to traditional antibiotic therapy.
Virome Analysis and Association of Positive Coxsackievirus B Serology during Pregnancy with Congenital Heart Disease
Authors: Garand Mathieu , Huang Susie S. Y. , Goessling Lisa S. , Wan Fei , Santillan Donna A. , Santillan Mark K. , Brar Anoop , Wylie Todd N. , Wylie Kristine M. , Eghtesady Pirooz
Published: January 2023

Background: We have previously shown coxsackievirus B (CVB) to be a potent inducer of congenital heart disease (CHD) in mice. The clinical relevance of these findings in humans and the roles of other viruses in the pathogenesis of CHD remain unknown. Methods: We obtained plasma samples, collected at all trimesters, from 89 subjects (104 pregnancies), 73 healthy controls (88 pregnancies), and 16 with CHD–affected birth (16 pregnancies), from the Perinatal Family Tissue Bank (PFTB). We performed CVB IgG/IgM serological assays on plasma. We also used ViroCap sequencing and PCR to test for viral nucleic acid in plasma, circulating leukocytes from the buffy coat, and in the media of a co-culture system. Results: CVB IgG/IgM results indicated that prior exposure was 7.8 times more common in the CHD group (95% CI, 1.14–54.24, adj. p-value = 0.036). However, the CVB viral genome was not detected in plasma, buffy coat, or co-culture supernatant by molecular assays, although other viruses were detected. Conclusion: Detection of viral nucleic acid in plasma was infrequent and specifically no CVB genome was detected. However, serology demonstrated that prior CVB exposure is higher in CHD-affected pregnancies. Further studies are warranted to understand the magnitude of the contribution of the maternal blood virome to the pathogenesis of CHD.
Analysis and Suppression of Crosstalk Beams in Microlens Array Scanning Imaging Optical System Based on the Combination of Multilayer Stop Arrays
Authors: Lv Zhiyang , Huang Yunhan , Liu Zhiying
Published: January 2023

The lateral displacement between the microlens arrays can realize the rapid deflection of a beam; however, in this process, crosstalk beams will inevitably occur between the microlens units, which will affect the imaging quality of the system. For this reason, we propose a crosstalk elimination design method based on the combination of multilayer stop arrays, establish a simulation model, use a geometric optical object image relationship to trace the characteristic light of a single group of microlenses, analyze the relationship between the structural parameters of the microlens array and the stop array size, and comprehensively discuss the light transmission of the microlens array under various conditions. An example of an infrared system is simulated using the optical design analysis software Fred, verifying the effectiveness of this design method in suppressing the crosstalk beams generated in the dynamic transmission process, ensuring independent propagation between microlens units, and realizing crosstalk-free imaging.
Preparation of Polymer Solution for Profile Control and Displacement Using Wastewater with High Ca2+/Mg2+ and Fe2+ Concentrations
Authors: Li Xuanran , Xu Anzhu , Ma Mengqi , Liu Shanglin , Ni Jun , Zhao Lun
Published: January 2023

In the present study, we used Kalamkas, which is a typical Kazakhstani oilfield, which produces wastewater with high Ca2+/Mg2+ and Fe2+ concentrations, as a case study. We investigated a method for preparing Fe2+ polymer solutions without oxygen isolation under the conditions of salinity >110 × 103 mg/L, Ca2+/Mg2+ concentration >7000 mg/L, and Fe2+ concentration >30 mg/L. Fe2+-resistant groups were grafted onto the molecular chains of a hydrophobically associating polymer prepared using existing synthesis technology to overcome the decrease in apparent viscosity of the polymer solution due to the oxidation of Fe2+ during solution preparation. The experiments showed that PAM-IR with iron-resistant groups can be completely dissolved in the wastewater within 180 min, and can tolerate an NaCl concentration of up to 0.23 × 106 mg/L, a Ca2+ concentration of up to 10 × 103 mg/L, an Mg2+ concentration of up to 9 × 103 mg/L, and a Fe2+ concentration of up to 90 mg/L, with favorable thickening performance and resistances to NaCl, Ca2+, Mg2+, and Fe2+. PAM-IR has good injection performance and can establish a high resistance factor (FR) and residual resistance factor (FRR) to increase the sweep efficiency. Therefore, it is potentially useful for enhancing oil recovery.
CFD Modeling and Validation of Blast Furnace Gas/Natural Gas Mixture Combustion in an Experimental Industrial Furnace
Authors: Arroyo Jorge , Pérez Luis , Cuervo-Piñera Víctor
Published: January 2023

The use of residual gases from steel production processes as fuel for steel treatment furnaces has attracted great interest as a method for reducing fossil fuel consumption and the steel footprint. However, these gases often have a low calorific value, and a direct substitution can lead to low temperatures or combustion instability issues. CFD simulations of the combustion of these gases can help steel producers forecast the results of the substitution before real testing and implementation. In this study, a CFD model of an industrial experimental furnace in the steel sector is developed and validated. The results are calculated using the combustion, radiation, and heat transfer models included in the software Ansys Fluent. The validation of the simulated results is performed with data acquired from experimental tests under the same simulated conditions at three air-to-fuel equivalence ratios, which vary from an excess of 0% to an excess of 5% oxygen at the outlet. The model is adjusted to the results, capturing the trends of the measured physical variables and pollutant concentrations. In the case of the combustion temperature, the differences between the simulated and measured values vary from 0.03% to 6.9. Based on the simulation results, the use of blast furnace gas as fuel produces temperatures inside the chamber between 1004 °C and 1075 °C and high stream velocities because of the high flow needed to keep the power constant. Flames exhibit straight movements since the high flows absorb the effect of the swirling flames. The addition of natural gases increases the combustion temperature up to 1211 °C and reduces the flow and length of the flames. Finally, temperatures up to 1298 °C and shorter flames are reached with natural gas enriched with a stream of oxygen, but in this case, NOx emissions need to be controlled.
Simple and Rigorous Proof Method for the Security of Practical Quantum Key Distribution in the Single-Qubit Regime Using Mismatched Basis Measurements
Authors: Boyer Michel , Brassard Gilles , Godbout Nicolas , Liss Rotem , Virally Stéphane
Published: January 2023

Quantum key distribution (QKD) protocols aim at allowing two parties to generate a secret shared key. While many QKD protocols have been proven unconditionally secure in theory, practical security analyses of experimental QKD implementations typically do not take into account all possible loopholes, and practical devices are still not fully characterized for obtaining tight and realistic key rates. We present a simple method of computing secure key rates for any practical implementation of discrete-variable QKD (which can also apply to measurement-device-independent QKD), initially in the single-qubit lossless regime, and we rigorously prove its unconditional security against any possible attack. We hope our method becomes one of the standard tools used for analysing, benchmarking, and standardizing all practical realizations of QKD.
Employing Molecular Docking Calculations for the Design of Alkyl (2-Alcoxy-2-Hydroxypropanoyl)-L-Tryptophanate Derivatives as Potential Inhibitors of 11β-Hydroxysteroid Dehydrogenase Type 1 (11β-HSD1)
Authors: Quiroga Diego
Published: January 2023

In this paper, we presented the design by computational tools of novel alkyl (2-alcoxy-2-hydroxypropanoyl)-L-tryptophanate derivatives, which can be potential inhibitors of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1). The molecular structure optimization of a group of 36 compounds was performed employing DFT-B3LYP calculations at the level 6-311G(d,p). Then, molecular docking calculations were performed using Autodock tools software, employing the Lamarckian genetic algorithm (LGA). Four parameters (binding, intermolecular and Van Der Waals hydrogen bonding desolvation energies, and HOMO-LUMO gap) were used to evaluate the potential as 11β-HSD1 inhibitors, which nominate L-tryptophan derivatives as the most promissory molecules. Finally, these molecules were obtained starting from the amino acid and pyruvic acid in a convergent methodology with moderate to low yields.
Religious Soft Power: Definition(s), Limits and Usage
Authors: Ozturk Ahmet Erdi
Published: January 2023

The following questions can be asked about the role of religion in global politics and discussions of its power position: (1) If religion is used as a soft power resource, how can we define it [...]
Analysis of GPS/EGNOS Positioning Quality Using Different Ionospheric Models in UAV Navigation
Authors: Grunwald Grzegorz , Ciećko Adam , Kozakiewicz Tomasz , Krasuski Kamil
Published: January 2023

Unmanned aerial vehicles (UAVs) have become very popular tools for geoinformation acquisition in recent years. They have also been applied in many other areas of life. Their navigation is highly dependent on global navigation satellite systems (GNSS). The European Geostationary Navigation Overlay Service (EGNOS) is intended to support GNSSs during positioning, mainly for aeronautical applications. The research presented in this paper concerns the analysis of the positioning quality of a modified GPS/EGNOS algorithm. The calculations focus on the source of ionospheric delay data as well as on the aspect of smoothing code observations with phase measurements. The modifications to the algorithm concerned the application of different ionospheric models for position calculation. Consideration was given to the EGNOS ionospheric model, the Klobuchar model applied to the GPS system, the Klobuchar model applied to the BeiDou system, and the NeQuick model applied to the Galileo system. The effect of removing ionospherical corrections from GPS/EGNOS positioning on the results of the determination of positioning quality was also analysed. The results showed that the original EGNOS ionospheric model maintains the best accuracy results and a better correlation between horizontal and vertical results than the other models examined. The additional use of phase-smoothing of code observations resulted in maximum horizontal errors of approximately 1.3 m and vertical errors of approximately 2.2 m. It should be noted that the results obtained have local characteristics related to the area of north-eastern Poland.
Nonlinear Vibration Control Experimental System Design of a Flexible Arm Using Interactive Actuations from Shape Memory Alloy
Authors: Li Ximei , Jin Guang , Deng Mingcong
Published: January 2023

The flexible arm easily vibrates due to its thin structural characteristics, which affect the operation accuracy, so reducing the vibration of the flexible arm is a significant issue. Smart materials are very widely used in the research topic of vibration suppression. Considering the hysteresis characteristic of the smart materials, based on previous simulation research, this paper proposes an experimental system design of nonlinear vibration control by using the interactive actuation from shape memory alloy (SMA) for a flexible arm. The experiment system was an interactive actuator–sensor–controller combination. The vibration suppression strategy was integrated with an operator-based vibration controller, a designed integral compensator and the designed n-times feedback loop. In detail, a nonlinear vibration controller based on operator theory was designed to guarantee the robust stability of the flexible arm. An integral compensator based on an estimation mechanism was designed to optimally reduce the displacement of the flexible arm. Obtaining the desired tracking performance of the flexible arm was a further step, by increasing the n-times feedback loop. From the three experimental cases, when the vibration controller was integrated with the designed integral compensator, the vibration displacement of the flexible arm was much reduced compared to that without the integral compensator. Increasing the number of n-times feedback loops improves the tracking performance. The desired vibration control performance can be satisfied when n tends to infinity. The conventional PD controller stabilizes the vibration displacement after the 7th vibration waveform, while the vibration displacement approaches zero after the 4th vibration waveform using the proposed vibration control method, which is proved to be faster and more effective in controlling the flexible arm’s vibration. The experimental cases verify the effectiveness of the proposed interactive actuation vibration control approach. It is observed from the experimental results that the vibration displacement of the flexible arm becomes almost zero within less time and with lower input power, compared with a traditional controller.
Quadriceps Muscle Morphology Is an Important Determinant of Maximal Isometric and Crank Torques of Cyclists
Authors: Lanferdini Fábio Juner , Diefenthaeler Fernando , Ávila Andressa Germann , Moro Antônio Renato Pereira , van der Zwaard Stephan , Vaz Marco Aurélio
Published: January 2023

The aim of this study was to determine if quadriceps morphology [muscle volume (MV); cross-sectional area (CSA)], vastus lateralis (VL) muscle architecture, and muscle quality [echo intensity (ECHO)] can explain differences in knee extensor maximal voluntary isometric contraction (MVIC), crank torque (CT) and time-to-exhaustion (TTE) in trained cyclists. Twenty male competitive cyclists performed a maximal incremental ramp to determine their maximal power output (POMAX). Muscle morphology (MV; CSA), muscle architecture of VL and muscle quality (ECHO) of both quadriceps muscles were assessed. Subsequently, cyclists performed three MVICs of both knee extensor muscles and finally performed a TTE test at POMAX with CT measurement during TTE. Stepwise multiple regression results revealed right quadriceps MV determined right MVIC (31%) and CT (33%). Left MV determined CT (24%); and left VL fascicle length (VL-FL) determined MVIC (64%). However, quadriceps morphological variables do not explain differences in TTE. No significant differences were observed between left and right quadriceps muscle morphology (p > 0.05). The findings emphasize that quadriceps MV is an important determinant of knee extensor MVIC and CT but does not explain differences in TTE at POMAX. Furthermore, quadriceps morphological variables were similar between the left and right quadriceps in competitive cyclists.
Normative Scores for CrossFit® Open Workouts: 2011–2022
Authors: Mangine Gerald T. , Grundlingh Nina , Feito Yuri
Published: January 2023

To create normative scores for all CrossFit® Open (CFO) workouts and compare male and female performances, official scores were collected from the official competition leaderboard for all competitors of the 2011–2022 CFO competitions. Percentiles were calculated for athletes (18–54 years) who completed all workouts within a single year ‘as prescribed’ and met minimum scoring thresholds. Independent t-tests revealed significant (p < 0.05) sex differences for 56 of 60 workouts. In workouts scored by repetitions completed, men completed more repetitions in 18 workouts by small to large differences (d = 0.22–0.81), whereas women completed more repetitions in 6 workouts by small to medium differences (d = 0.36–0.77). When workouts were scored by time to completion, men were faster in 10 workouts by small to large differences (d = 0.23–1.12), while women were faster in 3 workouts by small differences (d = 0.46). In three workouts scored by load lifted, men lifted more weight by large differences (d = 2.00–2.98). All other differences were either trivial or not significant. Despite adjusted programming for men and women, the persistence of performance differences across all CFO workouts suggests that resultant challenges are not the same. These normative values may be useful for training and research in male and female CrossFit® athletes.
Effects of Pb(II) and Zn(II) Contamination on Adsorption, Desorption and Degradation of Cry1Ac Toxin Identical to Bt Transgenic Poplar in Black Soil
Authors: Wang Yongji , Zhou Xueyong , Zhang Fenguo , Zhang Lihong , Yang Pingguo , Maimaitiniyazi Rehanguli
Published: January 2023

Bt transgenic white poplar has been commercially planted in China since 2002, and it showed obvious insect resistance in the field. However, the ecological risk of planting Bt transgenic poplar in a field contaminated with heavy metals has received little attention. The effects of Pb(II) and Zn(II) contamination on the adsorption, desorption and degradation of Bt toxin identical to Bt transgenic poplar in black soil were studied. The results showed that the adsorption of Bt toxin was enhanced and the desorption of Bt toxin was inhibited in black soil by Pb(II) and Zn(II) at concentrations between 0 and 1 mmol/L, and the effect of Pb(II) on Bt toxin was greater than that of Zn(II). In the presence of heavy metal ions, the Cry1Ac toxin molecules are oriented with domain I toward soil particles through the metal ion bridge. The promoting mechanism of Bt toxin adsorption by heavy metal ions in black soil is mainly attributed to cation-controlled electrostatic attraction (CCEA), which is different from patch-controlled electrostatic attraction (PCEA). With the increase in soil concentration from 1 to 4 mg/mL, the adsorption amount of Bt toxin showed a downward trend, and both Pb(II) and Zn(II) had the maximal promotion effect when the soil concentration was 2 mg/mL. The promoting effect of Zn(II) on the adsorption of Bt toxin increased with the increased temperature (5–45 °C), but the promoting effect of Pb(II) was maximal at 25 °C. Both Pb(II) and Zn(II) affected the degradation characteristics of Bt toxin in black soil. For the lead-contaminated black soil, the residual amount of Bt toxin increased in the early stage but decreased in the later stage compared to the control soil. For the zinc-contaminated black soil, the residual amount of Bt toxin decreased compared to the control soil except between the second and tenth days. In this study, it was observed that Bt toxin was degraded rapidly in the early stage, followed by a large amount of released Bt toxin and slow degradation in the middle and late stages.
Evolution of the Prevalence of Antibiotic Resistance to Staphylococcus spp. Isolated from Horses in Florida over a 10-Year Period
Authors: Marshall Kalie , Marsella Rosanna
Published: January 2023

Previous studies documented antibiotic resistance in horses but did not focus on skin specifically. We investigated antibiotic resistance and correlations between resistance patterns in skin infections. Records from 2009 to 2019 were searched for Staphylococcal infection and susceptibility results. Seventy-seven cases were included. Organisms identified were S. aureus (48/77), S. pseudintermedius (7/77), non-hemolytic Staphylococcus (8/77), beta-hemolytic Staphylococcus (6/77), and other species (8/77). Samples included pyoderma (36/77), wounds (10/77), abscesses (15/77), incision sites (5/77), nose (8/77), and foot (3/77). A trend analysis using non-parametric Spearman’s test showed significant upward trend of resistance (p < 0.05) for 3/15 antibiotics (ampicillin, cefazolin, penicillin). Susceptibility was significantly different by Staphylococcal species for 8/15 antibiotics. Gentamicin showed significant susceptibility differences based on source (all abscesses were susceptible to gentamicin). Steel-Dwass test showed statistically significant (p = 0.003) difference between incision sites and abscesses. A non-parametric Kendall’s T-test found significantly negative correlation between cefazolin and amikacin sensitivity (p = 0.0108) and multiple positive correlations of resistance (p < 0.05). This study confirms increasing resistance in dermatologic samples. It is unlikely that the sample source affects resistance, but Staphylococcus species may affect it. Study limitations include lack of information about previous antibiotic use and small sample size.
Quality of Life of Allergic Dogs Treated with Allergen-Specific Immunotherapy—A Retrospective Study
Authors: Kotnik Tina
Published: January 2023

Background: The quality of life (QoL) of dogs with canine atopic dermatitis (CAD) treated with allergen-specific immunotherapy (ASIT) was studied to determine whether the QoL of dogs treated with ASIT (AG) improved compared with dogs not treated with ASIT (CG). Methods: The power of the study was calculated in advance assuming that the AG would assess QoL 20% better than the CG. The CG consisted of 21 dogs with CAD and the AG of 46 dogs with CAD. Validated QoL1 (pre-treatment) and QoL2 (post-treatment) questionnaires were emailed to owners. Results: AG dogs were significantly less disturbed during mealtimes (i.e., had better appetites and scratched less during mealtimes) and caused significantly less physical discomfort to their owners (due to unpleasant odor, the impression of a dirty apartment) than CG dogs. Owners of dogs treated with ASIT were able to significantly improve their daily activities (leisure, vacation, walks, work, hunting), significantly reduce their expenses (treatment costs, veterinary costs), feel significantly less emotional distress (less guilt, powerlessness, sadness, regret, fear, anger, disgust, rage, frustration), and experience less influence on relationships with family members and friends compared to owners of dogs not treated with ASIT. Conclusions: According to our results, the quality of life of dogs treated with ASIT and their owners seemed to improve significantly.
Semen Quality Traits of Two Thai Native Chickens Producing a High and a Low of Semen Volumes
Authors: Mussa Ngassa Julius , Boonkum Wuttigrai , Chankitisakul Vibuntita
Published: January 2023

Semen quality traits such as semen volume, sperm motility, sperm concentration, pH, and color are very important, since they can determine the fertility potential of the semen. The objective of this study was to compare the semen quality traits of Thai Native chickens (Pradu Hang Dam and Chee) producing high and low semen volume. Semen was collected from 24 roosters (12 reps) and divided into two groups of roosters producing high semen volume (>0.3 mL) and those producing a low amount of semen (<0.3 mL). Fresh semen quality parameters (semen volume, sperm motility, viability, concentration, and pH) were measured and compared between groups. It was found that semen volume showed a positive correlation with sperm concentration, mass movement, motility, viability, and pH of fresh semen. There was no significant difference in fresh semen parameters between Pradu Hang Dam and Chee roosters with either high or low ejaculate semen, except for sperm concentration. Sperm concentration was significantly higher in Chee compared with Pradu Hang Dam in both high and low ejaculate semen. The semen quality parameters between groups of chickens producing high and low ejaculate semen were significantly different except for sperm viability. In conclusion, it was found that chickens producing high volumes of semen have better sperm quality than those producing a low semen volume. Therefore, these results provide a possible consideration that the amount of semen production among chickens can be used as a tool in selecting Thai native roosters for breeding.
Transcriptome RNA Sequencing Reveals That Circular RNAs Are Abundantly Expressed in Embryonic Breast Muscle of Duck
Authors: Liu Jing , Liu Shuibing , Zhang Wentao , Hu Xiaolong , Mao Huirong , Liu Sanfeng , Chen Biao
Published: January 2023

Circular RNAs are widespread in various species and have important roles in myogenesis. However, the circular RNAs involved in breast muscle development in ducks have not yet been studied. Here, to identify circular RNAs during duck skeletal muscle development, three pectorales from Shan Ma ducks at E13 and E19, which represent undifferentiated and differentiated myoblasts, respectively, were collected and subjected to RNA sequencing. A total of 16,622 circular RNAs were identified, of which approximately 80% were exonic circular RNAs and 260 were markedly differentially expressed between E19 and E13. The parental genes of the differentially expressed circular RNAs were significantly enriched in muscle-related biological processes. Moreover, we found that the overexpression of circGAS2-2 promoted cell cycle progression and increased the proliferation viability of duck primary myoblasts; conversely, knockdown of circGAS2-2 retarded the cell cycle and reduced the proliferation viability of myoblasts. Taken together, our results demonstrate that circular RNAs are widespread and variously expressed during the development of duck skeletal muscle and that circGAS2-2 is involved in the regulation of myogenesis.
Experimental Study on the Local Scour of Submerged Spur Dike Heads under the Protection of Soft Mattress in Plain Sand-Bed Rivers
Authors: Xu Hua , Li Yangfan , Zhao Zeya , Wang Xiaojun , Zhang Fanyi
Published: January 2023

Submerged spur dikes are widely applied in the channel regulation structures of plain sand-bed rivers such as the lower reaches of the Yangtze River; thus, the issue of local scour protection near regulating structures is especially important for structure design engineering. To further scientific research on the local scour of submerged spur dike heads, we investigated rulers describing the variance of the incoming flow dynamic, scale of the spur dike body, width of river bottom protection, etc., responding to the maximum local scouring depth of a submerged spur dike and the distance between the submerged spur dike and dam axis under the conditions of river bottom protection. According to principles of dimensional analysis, we established computational formulas for the maximum local scouring depth of a submerged spur dike and the distance between the submerged spur dike and dam axis, with consideration of bottom protection works for the remaining soft mattress. These research results not only enrich existing research on the calculation of local scour of channel-regulating structures, but they are also a relevant technical reference for the design of water conservancy and waterway engineering.
El lugar de América Latina en el tablero geopolítico ruso: ¿cambios en la ecuación estratégica tras el 24-F?
Authors: Marmeladova Sonia
Published: January 2023

La influencia de Rusia en América Latina y el Caribe (ALC) desde la aplicación de las sanciones por la anexión de Crimea en 2014 se enfrenta a serios retos. Las restricciones económicas y el incremento de las tarifas de transporte marítimo impuestos a Moscú afectaron negativamente la competitividad de sus productos de defensa en el mercado latinoamericano. El comercio bilateral, en sus mejores momentos, se situó alrededor del 2,4% en la estructura de las exportaciones de Rusia. Además, la cooperación en materia económica con Moscú está empeorando debido a la agresiva competencia de las empresas chi- nas y estadounidenses en la región. La diplomacia de vacunas debía abrir al Kremlin una ventana de oportunidades para redescubrir Latinoamérica, pero su alcance ha quedado mermado a causa de los daños reputacionales tras el 24-F. Sin embargo, la respuesta de ALC frente a la invasión, es una muestra de la escasa coherencia política regional: algunos países condenan los actos de Rusia (Argentina, Co- lombia, Chile, Paraguay y Uruguay), otros defienden la postura de que el Kremlin fue provocado (Cuba, Nicaragua, Venezuela y Bolivia), y en Brasil y México se ha producido una actitud ambivalente que revela visiones conflictivas entre la presidencia y la cancillería. Finalmente, también hay Estados que claramente pretenden beneficiarse de la confrontación entre Moscú y Washington (El Salvador, Hon- duras o Ecuador). Estas incoherencias demuestran que el Kremlin está capitalizando los beneficios de su estrategia de “bajo coste” a través de la presencia mediática, al tiempo que las naciones latinoame- ricanas no están dispuestas a involucrarse en la confrontación con Rusia por razones indirectas.
A Journal of Devotion
Authors: Spears Larry
Published: January 2023

With the publication of this first academic journal devoted to research and writing on servant-leadership, we hope to take significant step forward in the ongoiong evolution of servant-leadership. Much as the burgeoning field of philanthropic studies was some ten or fifteen years ago, the study of servant-leadership is now poised for a similar kind of development. The International Journal of Servant-leadership, a collaboration between Gonzaga University and The Greenleaf Center, has been established to help lead the way in the further development of servant-leadership as a legitimate and powerful field for study, research, teaching and publishing.
Book Review: Practicing Servant-Leadership: Succeeding Through Trust, Bravery, and Forgiveness
Authors: Carey Michael Lieberman
Published: January 2023

Michael Lieberman Carey reviews Practicing Servant-Leadership: Succeeding Through Trust, Bravery, and Forgiveness (2004) by Larry Spears and Michele Lawrence. Carey finds it to be a collection of "much-needed words, shedding light on an indispensible vision not only of a leadership concept, but also, significantly, of a way of life for our time."