bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental and Numerical Study of the Nonlinear Evolution of Regular Waves over a Permeable Submerged Breakwater
Authors: Wang Ping , Fang Kezhao , Wang Gang , Liu Zhongbo , Sun Jiawen
Published: August 2023

The permeable submerged breakwater has gained popularity in recent days due to its merits of reducing incident wave energy without negatively impacting the aesthetics of the ocean view and allowing for water exchange. However, the effect of porosity on wave nonlinearity and turbulence motion close to the water/structure interface is not well resolved in the literature. This paper presents an experimental and numerical study of regular wave propagation over a permeable submerged breakwater with a wide top width. The laboratory experiments were conducted in a wave flume and included 45 test cases. The numerical simulations were performed utilizing validated olaFoam. The results show that the nonlinearity of the waves on the permeable submerged breakwater is weak, which can effectively suppress and reduce the second harmonic waves. A large amount of turbulent kinetic energy exists at the interface between the permeable submerged breakwater and the water body, which helps to dissipate wave energy. For the wider permeable submerged breakwater in this paper, the wave dissipation capacity is greatest when the porosity is between 0.2 and 0.3, and as the length of the breakwater increases, the energy transmission coefficient decreases, and the energy dissipation coefficient increases. Better wave attenuation is achieved when the permeable submerged breakwater has a certain porosity and a large width.
Life-Cycle and Applicational Analysis of Hydrogen Production and Powered Inland Marine Vessels
Authors: Knight Matthew , Blanco-Davis Eduardo , Platt Oliver , Armin Milad
Published: August 2023

Green energy is at the forefront of current policy, research, and engineering, but some of the potential fuels require either a lot of deeper research, or a lot of infrastructure before they can be implemented. In the case of hydrogen both are true. This report aims to analyse the potential of hydrogen as a future fuel source by performing a life-cycle assessment. Through this the well-to-tank phase of fuel production, and the usage phase of the system have been analysed. Models have also been created for traditional fuel systems to best compare results. The results show that hydrogen has great potential to convert marine transport to operating off green fuels when powered through low-carbon energy sources, which could reduce a huge percentage of the international community’s greenhouse gas emissions. Hydrogen produced through wind powered alkaline electrolysis produced emission data 5.25 g of CO2 equivalent per MJ, compared to the 210 g per MJ produced by a medium efficiency diesel equivalent system, a result 40 times larger. However, with current infrastructure in most countries not utilising a great amount of green energy production, the effects of hydrogen usage could be more dangerous than current fuel sources, owing to the incredible energy requirements of hydrogen production, with even grid (UK) powered electrolysis producing an emission level of 284 g per MJ, which is an increase against standard diesel systems. From this the research concludes that without global infrastructure change, hydrogen will remain as a potential fuel rather than a common one.
Study on the Spatiotemporal Evolution of the “Contraction–Expansion” Change of the Boundary Area between Two Green Belts in Beijing Based on a Multi-Index System
Authors: Zhan Fangzhi , Liu Zhicheng , Wang Boya
Published: August 2023

In serving as a pivotal strategy for curbing urban sprawl, large-scale urban green belts, being a significant constituent of the urban green space, have been ubiquitously employed in the scheming and fabrication of green space systems in global megacities. Nevertheless, the disregard for research into the independent alteration mechanism of urban green space, coupled with the reactive approach of planning and construction and the singularity of quantitative indices, has engendered challenges in the creation of urban green belts. This paper presents an investigation into the juncture zone of two green belts in Beijing as a case study, erecting a “contraction–expansion” flux model of its green space and gauging the transformational traits of the green space in light of its spatial–temporal evolution with regards to its quantity, space, and connectivity among others. Findings reveal that between 2005 and 2012, the green space in Beijing underwent an approximately 20% alteration, with the green belt intersection zone’s green space area experiencing a dual trajectory shift of “expansion-contraction”. This shift was primarily characterized by expansion before 2015 and contraction from 2015 onwards. Concerning spatial attributes, patterns of expansion and aggregation were discernible in scattered distribution, whereas contraction and aggregation were evident in mass and spaced distribution. Spatial stability was influenced by the change model, marked by a shift in the center of gravity from a “north-south-east” orientation to a “northwest-southeast” direction. At the connectivity stratum, noticeable variations were witnessed in both the overall and local connectivity levels pre- and post-2015. Regarding individual connectivity, three vital nodes of stable linear connectivity were identified, playing a decisive role in defining the dispersion of crucial corridors within the area of study.
Assessment of the Ecological Condition of Informal Settlements Using the Settlement Surface Ecological Index
Authors: Mudau Naledzani , Mhangara Paidamwoyo
Published: August 2023

To manage urban ecological ecosystems adequately, understanding the urban areas’ biophysical characteristics is required. This study developed a settlement surface ecological index (SSEI) using tree, soil, impervious surface and grass covers, land surface temperature (LST), and soil moisture derived from Satellite Pour L’Observation de la Terre (SPOT) 7 and Landsat 8 satellite images. The assessment of the SSEI was conducted over twelve sites of 300 m by 300 m. The selected sites contained formal and informal settlements of varying building densities. The SSEI values ranged from −0.3 to 0.54. Seven assessed areas are in the worst ecological condition with an SSEI below zero. Only three settlement types had an SSEI index value of 0.2 and above, and two of these areas were informal settlements. The formal low-density settlement with higher tree coverage displayed the highest index value of 0.54, slightly higher than the medium-density informal settlement. Overall, there is no significant difference in the SSEI values between the surface ecological condition of formal and informal settlements. The results achieved in this study can be used to understand urban ecology better and develop urban greening strategies at a city or settlement level.
Study on a Novel Strategy for High-Quality Grinding Surface Based on the Coefficient of Friction
Authors: Li Yang , Jiao Li , Liu Yanhou , Tian Yebing , Qiu Tianyang , Zhou Tianfeng , Wang Xibin , Zhao Bin
Published: August 2023

Surface quality has a significant impact on the service life of machine parts. Grinding is often the last process to ensure surface quality and accuracy of material formation. In this study, a high-quality surface was developed by determining the coefficient of friction in grinding a quartz fiber-reinforced silica ceramic composite. By processing the physical signals in the grinding process, a multi-objective function was established by considering grinding parameters, i.e., surface roughness, coefficient of friction, active energy consumption, and effective grinding time. The weight vector coefficients of the sub-objective functions were optimized through a multi-objective evolutionary algorithm based on the decomposition (MOEA/D) algorithm. The genetic algorithm was used to optimize the process parameters of the multi-objective function, and the optimal range for the coefficient of friction was determined to be 0.197~0.216. The experimental results indicated that when the coefficient of friction tends to 0.197, the distribution distance of the microscopic data points on the surface profile is small and the distribution uniformity is good. When the coefficient of friction tends to 0.216, the surface profile shows a good periodic characteristic. The quality of a grinding surface depends on the uniformity and periodicity of the surface’s topography. The coefficient of friction explained the typical physical characteristics of high-quality grinding surfaces. The multi-objective optimization function was even more important for the subsequent high-quality machining of mechanical parts to provide guidance and reference significance.
Hybrid Method with Parallel-Factor Theory, a Support Vector Machine, and Particle Filter Optimization for Intelligent Machinery Failure Identification
Authors: Li Shaoyi , Chen Hanxin , Chen Yongting , Xiong Yunwei , Song Ziwei
Published: August 2023

Here, a novel hybrid method of intelligent fault identification within complex mechanical systems was proposed using parallel-factor (PARAFAC) theory and adaptive particle swarm optimization (APSO) for a support vector machine (SVM). The parallel-factor multi-scale analysis theory was studied to reconstruct tensor feature information based on a three-dimensional matrix for time, frequency, and spatial vectors. A multi-scale wavelet analysis was used to transform the original multi-channel experimental data acquired from a gearbox into a three-dimensional feature matrix of the multi-level structure. The optimal correspondence among the two-dimensional feature signals in the frequency and time domains for the different fault modes was established by the PARAFAC theory. An intelligent APSO algorithm was developed to obtain the optimal parameter structures of an SVM classifier. A comparison with the existing time–frequency analysis method showed that the proposed hybrid PARAFAC-PSO-SVM diagnosis model effectively eliminated the redundant information in the multi-dimensional tensor features but retained the important components. The PARAFAC-APSO-SVM hybrid diagnostic model achieved fast, accurate, and simple fault-classification and identification results, and could provide theoretical support for the application of the PARAFAC theory to complex mechanical fault diagnosis.
Human–Machine Shared Steering Control for Vehicle Lane Changing Using Adaptive Game Strategy
Authors: Wu Xiaodong , Su Chengrui , Yan Liang
Published: August 2023

Human–machine shared control of intelligent vehicles is considered an important technology during the industrial application of autonomous driving systems. Among the engineering practices in driver assistance systems, shared steering control is one of the important applications for the human–machine interaction. However, how to deal with human–machine conflicts during emergency scenarios is the main challenge for the controller’s design. Most shared control approaches usually generate machine-oriented results without enough attention to the driver’s reaction. By taking the human driver and machine system as two intelligent agents, this paper proposes a game-based control scheme to achieve a dynamic authority allocation during the lane changing maneuver. Based on the modeling of predicted trajectories of the human driver, a human-intention-based shared steering control is designed to achieve dynamic Nash game equilibrium. Moreover, a human-oriented shared steering mechanism is employed to not only benefit from automated machine assistance, but also make full play of human contributions. Using quantitative comparative analysis in lane changing scenarios with different human–machine conflicts, a better performance by considering both driving comfort and safety is achieved.
Non-Convex Optimization: Using Preconditioning Matrices for Optimally Improving Variable Bounds in Linear Relaxations
Authors: Reyes Victor , Araya Ignacio
Published: August 2023

The performance of branch-and-bound algorithms for solving non-convex optimization problems greatly depends on convex relaxation techniques. They generate convex regions which are used for improving the bounds of variable domains. In particular, convex polyhedral regions can be represented by a linear system A.x=b. Then, bounds of variable domains can be improved by minimizing and maximizing variables in the linear system. Reducing or contracting optimally variable domains in linear systems, however, is an expensive task. It requires solving up to two linear programs for each variable (one for each variable bound). Suboptimal strategies, such as preconditioning, may offer satisfactory approximations of the optimal reduction at a lower cost. In non-square linear systems, a preconditioner P can be chosen such that P.A is close to a diagonal matrix. Thus, the projection of the equivalent system P.A.x=P.b over x, by using an iterative method such as Gauss–Seidel, can significantly improve the contraction. In this paper, we show how to generate an optimal preconditioner, i.e., a preconditioner that helps the Gauss–Seidel method to optimally reduce the variable domains. Despite the cost of generating the preconditioner, it can be re-used in sub-regions of the search space without losing too much effectiveness. Experimental results show that, when used for reducing domains in non-square linear systems, the approach is significantly more effective than Gauss-based elimination techniques. Finally, the approach also shows promising results when used as a component of a solver for non-convex optimization problems.
A Heuristic Model for Spare Parts Stocking Based on Markov Chains
Authors: Pacheco-Velázquez Ernesto Armando , Robles-Cárdenas Manuel , Juárez Ordóñez Saúl , Damy Solís Abelardo Ernesto , Cárdenas-Barrón Leopoldo Eduardo
Published: August 2023

Spare parts management has gained significant attention in recent years due to the considerable costs associated with backorders or excess inventory. This article addresses the challenge of determining the optimal number of spare parts to stock, assuming that the parts can be repaired. When an item fails, it is promptly sent for repair in a workshop. The time between failures and the repair time are assumed to follow an exponential distribution, although it should be noted that the results could be adapted to other distributions as well. This study introduces a heuristic method to find the optimal inventory level that minimizes the total cost, considering holding inventory, backorder, and repair costs. The research offers a valuable decision-making framework for determining the number of spare parts needed to minimize inventory costs, based on just two parameters: (1) the ratio of time to repair and time to failure, and (2) the ratio of the inventory holding cost of a spare part per day to the daily cost of an idle machine. To the best of our knowledge, there are no similar methodologies in the existing literature. The proposed method is straightforward to implement, employing graphs and simple computations. Therefore, it is anticipated to be highly beneficial for practitioners seeking a quick and reliable estimator of the optimal number of spare parts to stock for critical components.
Does a New Electric Vehicle Manufacturer Have the Incentive for Battery Life Investment? A Study Based on the Game Framework
Authors: Wang Zongxian , Li Xiao , Liang Weihua , Ma Junhai
Published: August 2023

Motivated by the electric vehicle battery life performance, we studied the optimal investment decision-making behaviour of duopoly automakers. Based on the framework of game theory, this paper explores the influence of various parameters in the static game and dynamic game on the results, in combination with consumers’ preference for the battery life of electric vehicles. In the static game, a smaller investment coefficient is more beneficial to a firm that adopts an investment strategy rather than a firm that does not. When the investment coefficient increases, the difference between the two manufacturers will become smaller. The change of parameters in the dynamic game system may lead to complex dynamic phenomena, and the system will experience period-doubling bifurcation and N-S bifurcation from a stable state into a chaotic state. It will also significantly impact the basins of attraction, which affect the decision-makers’ initial choice. Consequently, we can use the control method to return the unstable system to stability. Based on these findings, some management insights and suggestions are presented.
Survey of Point Cloud Registration Methods and New Statistical Approach
Authors: Marek Jaroslav , Chmelař Pavel
Published: August 2023

The use of a 3D range scanning device for autonomous object description or unknown environment mapping leads to the necessity of improving computer methods based on identical point pairs from different point clouds (so-called registration problem). The registration problem and three-dimensional transformation of coordinates still require further research. The paper attempts to guide the reader through the vast field of existing registration methods so that he can choose the appropriate approach for his particular problem. Furthermore, the article contains a regression method that enables the estimation of the covariance matrix of the transformation parameters and the calculation of the uncertainty of the estimated points. This makes it possible to extend existing registration methods with uncertainty estimates and to improve knowledge about the performed registration. The paper’s primary purpose is to present a survey of known methods and basic estimation theory concepts for the point cloud registration problem. The focus will be on the guiding principles of the estimation theory: ICP algorithm; Normal Distribution Transform; Feature-based registration; Iterative dual correspondences; Probabilistic iterative correspondence method; Point-based registration; Quadratic patches; Likelihood-field matching; Conditional random fields; Branch-and-bound registration; PointReg. The secondary purpose of this article is to show an innovative statistical model for this transformation problem. The new theory needs known covariance matrices of identical point coordinates. An unknown rotation matrix and shift vector have been estimated using a nonlinear regression model with nonlinear constraints. The paper ends with a relevant numerical example.
New Machine-Learning Control Charts for Simultaneous Monitoring of Multivariate Normal Process Parameters with Detection and Identification
Authors: Sabahno Hamed , Niaki Seyed Taghi Akhavan
Published: August 2023

Simultaneous monitoring of the process parameters in a multivariate normal process has caught researchers’ attention during the last two decades. However, only statistical control charts have been developed so far for this purpose. On the other hand, machine-learning (ML) techniques have rarely been developed to be used in control charts. In this paper, three ML control charts are proposed using the concepts of artificial neural networks, support vector machines, and random forests techniques. These ML techniques are trained to obtain linear outputs, and then based on the concepts of memory-less control charts, the process is classified into in-control or out-of-control states. Two different input scenarios and two different training methods are used for the proposed ML structures. In addition, two different process control scenarios are utilized. In one, the goal is only the detection of the out-of-control situation. In the other one, the identification of the responsible variable (s)/process parameter (s) for the out-of-control signal is also an aim (detection–identification). After developing the ML control charts for each scenario, we compare them to one another, as well as to the most recently developed statistical control charts. The results show significantly better performance of the proposed ML control charts against the traditional memory-less statistical control charts in most compared cases. Finally, an illustrative example is presented to show how the proposed scheme can be implemented in a healthcare process.
Trichoderols B-G, Six New Lipids from the Marine Algicolous Fungus Trichoderma sp. Z43
Authors: Shi Zhen-Zhen , Yin Xiu-Li , Ji Nai-Yun
Published: August 2023

Six new lipids, trichoderols B-G (1–6), along with a known one, triharzianin B (7), were isolated from the culture of Trichoderma sp. Z43 obtained from the surface of the marine brown alga Dictyopteris divaricata. Their structures and relative configurations were identified by interpretation of 1D/2D NMR and MS data. Compounds 1–7 were assayed for inhibiting the growth of three phytopathogenic fungi (Fusarium graminearum, Gaeumannomyces graminis, and Glomerella cingulata), four marine phytoplankton species (Amphidinium carterae, Heterocapsa circularisquama, Heterosigma akashiwo, and Prorocentrum donghaiense), and one marine zooplankton (Artemia salina). Compounds 1, 4, and 7 exhibited weak antifungal activities against three phytopathogenic fungi tested with MIC ≥ 64 μg/mL. All compounds displayed moderate antimicroalgal activity with IC50 ≥ 15 μg/mL and low toxicity to the brine shrimp Artemia salina.
The mTOR Inhibitor Rapamycin Counteracts Follicle Activation Induced by Ovarian Cryopreservation in Murine Transplantation Models
Authors: Bindels Jules , Squatrito Marlyne , Bernet Laëtitia , Nisolle Michelle , Henry Laurie , Munaut Carine
Published: August 2023

Background and Objectives: Ovarian tissue cryopreservation followed by autotransplantation (OTCTP) is currently the only fertility preservation option for prepubertal patients. Once in remission, the autotransplantation of frozen/thawed tissue is performed when patients want to conceive. A major issue of the procedure is follicular loss directly after grafting mainly due to follicle activation. To improve follicular survival during the OTCTP procedure, we inhibited the mTOR pathway involved in follicle activation using rapamycin, an mTOR inhibitor. Next, we compared two different in vivo models of transplantation: the recently described non-invasive heterotopic transplantation model between the skin layers of the ears, and the more conventional and invasive transplantation under the kidney capsule. Materials and Methods: To study the effects of adding rapamycin during cryopreservation, 4-week-old C57BL/6 mouse ovaries, either fresh, slow-frozen, or slow-frozen with rapamycin, were autotransplanted under the kidney capsule of mice and recovered three weeks later for immunohistochemical (IHC) analysis. To compare the ear with the kidney capsule transplantation model, fresh 4-week-old C57BL/6 mouse ovaries were autotransplanted to either site, followed by an injection of either LY294002, a PI3K inhibitor, vehicle control, or neither, and these were recovered three weeks later for IHC analysis. Results: Rapamycin counteracts cryopreservation-induced follicle proliferation, as well as AKT and mTOR pathway activation, in ovaries autotransplanted for three weeks under the kidney capsule of mice. Analyses of follicle proliferation, mTOR activation, and the effects of LY294002 treatment were similar in transplanted ovaries using either the ear or kidney capsule transplantation model. Conclusions: By adding rapamycin during the OTCTP procedure, we were able to transiently maintain primordial follicles in a quiescent state. This is a promising method for improving the longevity of the ovarian graft. Furthermore, both the ear and kidney capsule transplantation models were suitable for investigating follicle activation and proliferation and pharmacological strategies.
Association of Scapular Dyskinesis with Neck and Shoulder Function and Training Period in Brazilian Ju-Jitsu Athletes
Authors: Jeong Ji Hyeon , Kim Young Kyun
Published: August 2023

Background and Objectives: Neck and shoulder injuries are common in Brazilian ju-jitsu (BJJ) athletes, and scapular dyskinesis (SD) is associated with these injuries. This study aimed to investigate the prevalence of SD in BJJ athletes, their neck and shoulder function and strength, and the BJJ training period. Materials and Methods: Forty-eight BJJ athletes participated in the study. Years of experience with BJJ, belt, shoulder internal and external rotation strength, neck strength, neck disability index (NDI), and SD were measured. Results: Approximately 31 BJJ athletes (64.6%) showed SD, and the nondominant arm showed a more obvious SD (n = 22, 45.8%) than the dominant arm (n = 18, 37.5%). Those with over five years of BJJ training experience showed a significantly higher rate of SD (p = 0.006) than those with less than five years of experience. Shoulder isometric internal rotation strength was significantly weaker in the obvious SD group than in the normal SD group (p = 0.014). Neck isometric strength and NDI did not differ significantly between individuals with or without SD. Conclusions: SD was common among BJJ athletes, and more experienced BJJ athletes exhibited higher rates of SD. Shoulder rotational strength was weaker with SD. Further studies are necessary on the neck and shoulders of BJJ athletes with SD.
Clinical Effectiveness of Mirogabalin Besylate for Trigeminal Neuropathy after Skull Base Surgery: Illustrative Cases
Authors: Karatsu Kosuke , Tamura Ryota , Miyauchi Tsubasa , Sogano Junki , Hino Utaro , Iwama Takashi , Toda Masahiro
Published: August 2023

Background: Postoperative trigeminal neuropathy may be seen after surgery for middle and posterior cranial fossa lesions. Although neuropathic pain is a cause of reduced quality of life, global consensus on postoperative pain management is lacking. Mirogabalin besylate is a selective ligand for the α2δ subunit of voltage-gated calcium channels. Although mirogabalin has been used for patients with postherpetic neuralgia and painful diabetic peripheral neuropathy, few reports have assessed the effect on postsurgical neuropathy. In this report, we describe a clinical effectiveness of mirogabalin for trigeminal neuropathy after skull base surgery. Case description: Case 1: A 51-year-old female with right trigeminal schwannoma was operated on via the anterior transpetrosal approach. She had tingling and numb feelings in the right face postoperatively. Mirogabalin was orally administered after the operation. Her continuous facial numbness immediately improved. Case 2: A 55-year-old female with left middle fossa base meningioma extending into the infratemporal fossa was operated on via the infratemporal fossa approach. She had a tingling feeling in the left face postoperatively. Mirogabalin was orally administered for this symptom after the operation, which gradually improved. Conclusions: Mirogabalin may show significant pain relief for patients with trigeminal neuropathy after skull base surgery. Further studies using a larger number of patients are warranted to confirm these findings.
Perceived Distributed Leadership, Job Satisfaction, and Professional Satisfaction among Academics in Guanajuato Universities
Authors: Cano Ibarra Salustia Teresa , Carranza Maria Teresa De La Garza , Morales Patricia Galvan , Farias Jose Porfirio Gonzalez
Published: August 2023

The objective of this research was to identify the relationships between the variables of job satisfaction, professional satisfaction, distributed leadership, and the perception of insecurity in academics at five universities located in the state of Guanajuato. The research was of a non-experimental type and, according to its temporality, cross-sectional, because it was developed at a specific moment. The study is also descriptive and correlational, because it analyzes the degree of association between the variables. Finally, an exploratory factor analysis study was carried out (AFE). The results revealed that the relationship between the variables of job satisfaction and professional satisfaction was positive and significant, the relationship between the variables of distributed leadership and the perception of insecurity was positive but not significant, and the relationship between the variables of the perception of insecurity and the distribution of leadership was positive and significant. The relationship between the perception of insecurity and job satisfaction was positive but not significant. In the analysis of the control variables of sex, marital status, type of university, and level of studies with the dependent variable of job satisfaction, statistical tests were carried out to verify the existence of the significant differences between the groups. Furthermore, this analysis was conducted in relation to the variables of sex, marital status, and type of university.
Phage-Based Biosensing for Rapid and Specific Detection of Staphylococcus aureus
Authors: Li Ruining , Li Zhiwei , Huang Chenxi , Ding Yifeng , Wang Jia , Wang Xiaohong
Published: August 2023

Staphylococcus aureus (S. aureus) is a major foodborne pathogen. Rapid and specific detection is crucial for controlling staphylococcal food poisoning. This study reported a Staphylococcus phage named LSA2302 showing great potential for applications in the rapid detection of S. aureus. Its biological characteristics were identified, including growth properties and stability under different pH and temperature conditions. The genomic analysis revealed that the phage has no genes associated with pathogenicity or drug resistance. Then, the phage-functionalized magnetic beads (pMB), serving as a biological recognition element, were integrated with ATP bioluminescence assays to establish a biosensing method for S. aureus detection. The pMB enrichment brought high specificity and a tenfold increase in analytical sensitivity during detection. The whole detection process could be completed within 30 min, with a broad linear range of 1 × 104 to 1 × 108 CFU/mL and a limit of detection (LOD) of 2.43 × 103 CFU/mL. After a 2 h pre-cultivation, this method is capable of detecting bacteria as low as 1 CFU/mL. The recoveries of S. aureus in spiked skim milk and chicken samples were 81.07% to 99.17% and 86.98% to 104.62%, respectively. Our results indicated that phage-based biosensing can contribute to the detection of target pathogens in foods.
Environmental Sampling Methods for Detection of Salmonella Infections in Laying Hens: A Systematic Review and Meta-Analysis
Authors: Pacholewicz Ewa , Wisselink Henk J. , Koene Miriam G. J. , van der Most Marleen , Gonzales Jose L.
Published: August 2023

Salmonellosis is the second most commonly reported foodborne gastrointestinal infection in humans in the European Union (EU). Most outbreaks are caused by Salmonella Enteritidis, present in contaminated food products, particularly in egg and egg products. In recent years, an increase in the prevalence of Salmonella in laying hen flocks in the EU has been observed. For the effective control of infection, adequate detection is key. In laying hen flocks, the occurrence of Salmonella in the EU is monitored by the culture of environmental samples (dust, faeces, and boot swabs). The performance of sampling procedures described in the literature for the detection of Salmonella in laying hens was reviewed. In total, 924 abstracts were screened, resulting in the selection of 87 abstracts and 18 publications for qualitative and quantitative analyses, respectively. Sample sizes and sampling locations of faecal material and dust were variable and poorly described. Microbiological culture methods used to detect Salmonella were variably described in the literature and were often incomplete. Overall, the available literature indicates higher sensitivity of environmental versus individual hen matrices and points to differences in sensitivity between environmental matrices. For non-cage housing systems, boot swabs are the preferred samples, while for cage housing systems dust might be a more reliable sample.
Type I Interferon Pathway-Related Hub Genes as a Potential Therapeutic Target for SARS-CoV-2 Omicron Variant-Induced Symptoms
Authors: Lin Zhiwei , Xue Mingshan , Wu Ziman , Liu Ze , Yang Qianyue , Hu Jiaqing , Peng Jiacong , Yu Lin , Sun Baoqing
Published: August 2023

Background: The global pandemic of COVID-19 is caused by the rapidly evolving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The clinical presentation of SARS-CoV-2 Omicron variant infection varies from asymptomatic to severe disease with diverse symptoms. However, the underlying mechanisms responsible for these symptoms remain incompletely understood. Methods: Transcriptome datasets from peripheral blood mononuclear cells (PBMCs) of COVID-19 patients infected with the Omicron variant and healthy volunteers were obtained from public databases. A comprehensive bioinformatics analysis was performed to identify hub genes associated with the Omicron variant. Hub genes were validated using quantitative RT-qPCR and clinical data. DSigDB database predicted potential therapeutic agents. Results: Seven hub genes (IFI44, IFI44L, MX1, OAS3, USP18, IFI27, and ISG15) were potential biomarkers for Omicron infection’s symptomatic diagnosis and treatment. Type I interferon-related hub genes regulated Omicron-induced symptoms, which is supported by independent datasets and RT-qPCR validation. Immune cell analysis showed elevated monocytes and reduced lymphocytes in COVID-19 patients, which is consistent with retrospective clinical data. Additionally, ten potential therapeutic agents were screened for COVID-19 treatment, targeting the hub genes. Conclusions: This study provides insights into the mechanisms underlying type I interferon-related pathways in the development and recovery of COVID-19 symptoms during Omicron infection. Seven hub genes were identified as promising biological biomarkers for diagnosing and treating Omicron infection. The identified biomarkers and potential therapeutic agent offer valuable implications for Omicron’s clinical manifestations and treatment strategies.
Biofilm Removal from In Vitro Narrow Geometries Using Single and Dual Pulse Er:YAG Laser Photoacoustic Irrigation
Authors: Terlep Saša , Dogsa Iztok , Pajk Franja , Stopar David
Published: August 2023

The disinfection and removal of biofilm from titanium dental implants remains a great challenge in oral medicine. Here we present results of novel photoacoustic irrigation laser modalities for biofilm removal in model geometries mimicking the peri-implant pocket. The efficacy of single pulse (Er:YAG-SSP) and dual pulse (Er:YAG-AutoSWEEPS) photoacoustic irrigation modalities were determined for Enterococcus faecalis biofilm decontamination from titanium surfaces in narrow cylindrical and square gap geometries. The density of bacteria as well as the number of live bacteria were determined prior and after different photoacoustic treatments. Both SSP and AutoSWEEPS photoacoustic irrigation techniques removed at least 92% of biofilm bacteria during the 10 s photoacoustic treatment. The effectiveness of cleaning was better in the narrow square gap geometry compared to the cylindrical geometry. The dual pulse Er:YAG-AutoSWEEPS photoacoustic irrigation showed better results compared to SSP modality. No chemical adjuvants were needed to boost the effectiveness of the photoacoustic irrigation in the saline solution. The results imply that photoacoustic irrigation is an efficient cleaning method for debridement and decontamination in narrow geometries and should be considered as a new therapeutic option for the treatment of peri-implant diseases.
Interaction and Metabolic Function of Microbiota during the Washed Processing of Coffea arabica
Authors: Shen Xiaojing , Wang Baijuan , Zi Chengting , Huang Lulu , Wang Qi , Zhou Chenchen , Wen Wu , Liu Kunyi , Yuan Wenjuan , Li Xingyu
Published: August 2023

Coffee fermentation is crucial for flavor and aroma, as microorganisms degrade mucilage and produce metabolites. This study aimed to provide a basis for understanding the impact of microorganisms on Coffea arabica from Yunnan, China, during washed processing. The microbial community structure and differentially changed metabolites (DCMs) of C. arabica beans during washed processing were analyzed. The results indicated that the top five predominant microorganisms at the genera level were Achromobacter, Tatumella, Weissella, Streptococcus, and Trichocoleus for bacteria and Cystofilobasidium, Hanseniaspora, Lachancea, Wickerhamomyces, and Aspergillus for fungi. Meanwhile, the relative content of 115 DCMs in 36 h samples decreased significantly, compared to non-fermentation coffee samples (VIP > 1, p < 0.05, FC < 0.65), and the relative content of 28 DCMs increased significantly (VIP > 1, p < 0.05, FC > 1.5). Furthermore, 17 DCMs showed a strong positive correlation with microorganisms, and 5 DCMs had a strong negative correlation (p < 0.05, |r| > 0.6). Therefore, the interaction and metabolic function of microbiota play a key role in the formation of coffee flavor, and these results help in clarifying the fermentation mechanisms of C. arabica and in controlling and improving the quality of coffee flavor.
Metal–Organic Frameworks as Formose Reaction Catalysts with Enhanced Selectivity
Authors: Balloi Valentina , Diaz-Perez Manuel Antonio , Lara-Angulo Mayra Anabel , Villalgordo-Hernández David , Narciso Javier , Ramos-Fernandez Enrique V. , Serrano-Ruiz Juan Carlos
Published: August 2023

The formose reaction is an autocatalytic series of aldol condensations that allows one to obtain monosaccharides from formaldehyde. The formose reaction suffers from a lack of selectivity, which hinders practical applications at the industrial level. Over the years, many attempts have been made to overcome this selectivity issue, with modest results. Heterogeneous porous catalysts with acid–base properties, such as Metal–Organic Frameworks (MOFs), can offer advantages compared to homogeneous strong bases (e.g., calcium hydroxide) for increasing the selectivity of this important reaction. For the very first time, four different Zeolite Imidazolate Frameworks are presented in this work as catalysts for the formose reaction in liquid phase, and their catalytic performances were compared with those of the typical homogeneous catalyst (i.e., calcium hydroxide). The heterogeneous nature of the catalysis, the possible contribution of leached metal or linkers to the solution, and the stability of the materials were investigated. The porous structure of these solids and their mild basicity make them suitable for obtaining enhanced selectivity at 30% formaldehyde conversion. Most of the MOFs tested showed low structural stability under reaction conditions, thereby indicating the need to search for new MOF families with higher robustness. However, this important result opens the path for future research on porous heterogeneous basic catalysts for the formose reaction.
Trivinylphosphine Oxide: Synthesis, Characterization, and Polymerization Reactivity Investigated Using Single-Crystal Analysis and Density Functional Theory
Authors: Salmeia Khalifah A. , Afaneh Akef T. , Habash Reem R. , Neels Antonia
Published: August 2023

Organophosphorus chemicals are versatile and important in industry. Trivinylphosphine oxide (TVPO), for example, exhibited a promising precursor as a flame-retardant additive for industrial applications. Density functional theory (DFT) simulations were used to explore the kinetic and thermodynamic chemical processes underlying the nucleophilic addition reactions of TVPO in order to better understand their polymerization mechanisms. An experimental X-ray single-crystal study of TVPO supported this work’s theory based on its computed findings. TVPO was prepared using POCl3 and VMB in a temperature-dependent reaction. TVPO, the thermodynamically favourable product, is preferentially produced at low temperatures. The endothermic anionic addition polymerization reaction between TVPO and VMB begins when the reaction temperature rises. An implicit solvation model simulated TVPO and piperazine reactions in water, whereas a hybrid model modelled VMB interactions in tetrahydrofuran. The simulations showed a pseudo-Michael addition reaction mechanism with a four-membered ring transition state. The Michael addition reaction is analogous to this process.
Multi-Functional Chitosan Nanovesicles Loaded with Bioactive Manganese for Potential Wound Healing Applications
Authors: Davidson Edwin , Pereira Jorge , Gan Giannelli Giuliana , Murphy Zachary , Anagnostopoulos Vasileios , Santra Swadeshmukul
Published: August 2023

Chronic skin wound is a chronic illness that possesses a risk of infection and sepsis. In particular, infections associated with antibiotic-resistant bacterial strains are challenging to treat. To combat this challenge, a suitable alternative that is complementary to antibiotics is desired for wound healing. In this work, we report multi-functional nanoscale chitosan vesicles loaded with manganese (Chi-Mn) that has potential to serve as a new tool to augment traditional antibiotic treatment for skin wound healing. Chi-Mn showed antioxidant activity increase over time as well as antimicrobial activity against E. coli and P. aeruginosa PA01. The modified motility assay that mimicked a skin wound before bacterial colonization showed inhibition of bacterial growth with Chi-Mn treatment at a low area density of 0.04 µg of Mn per cm2. Furthermore, this study demonstrated the compatibility of Chi-Mn with a commercial antibiotic showing no loss of antimicrobial potency. In vitro cytotoxicity of Chi-Mn was assessed with macrophages and dermal cell lines (J774A.1 and HDF) elucidating biocompatibility at a wide range (2 ppm–256 ppm). A scratch wound assay involving human dermal fibroblast (HDF) cells was performed to assess any negative effect of Chi-Mn on cell migration. Confocal microscopy study confirmed that Chi-Mn tested at the MIC (16 ppm Mn) has no effect on cell migration with respect to control. Overall, this study demonstrated the potential of Chi-Mn nanovesicles for wound healing applications.
The Influence of the Sous Vide Cooking Time on Selected Characteristics of Pork Lion
Authors: Rezler Ryszard , Krzywdzińska-Bartkowiak Mirosława , Piątek Michał
Published: August 2023

The aim of this study was to determine the effect of sous vide and pressure-cooker cooking of pork muscles (Longissimus lumborum) on the physicochemical and technological characteristics of pork. The study included an analysis of the basic composition, colour, texture, sensory evaluation, nutritional value (vitamin B1 content), and rheological properties of meat cooked at 60 °C for 6–18 h and, for comparison, in an autoclave at 121.1 °C. The heating conditions affected the weight loss, colour, thiamine content, texture, and rheological properties of the meat. As the heating time increased, the texture determinants of firmness and chewiness decreased, which resulted in softer meat. The differences in the rheological properties of the sous-vide- and autoclave-cooked meat resulted from the different organisation of the spatial matrix of proteins and changes in the structure of muscle fibres caused by the high temperature.
Ecotoxicity of Diazinon and Atrazine Mixtures after Ozonation Catalyzed by Na+ and Fe2+ Exchanged Montmorillonites on Lemna minor
Authors: Benghaffour Amina , Azzouz Abdelkrim , Dewez David
Published: August 2023

The toxicity of two pesticides, diazinon (DAZ) and atrazine (ATR), before and after montmorillonite-catalyzed ozonation was comparatively investigated on the duckweed Lemna minor. The results allowed demonstrating the role of clay-containing media in the evolution in time of pesticide negative impact on L. minor plants. Pesticides conversion exceeded 94% after 30 min of ozonation in the presence of both Na+ and Fe2+ exchanged montmorillonites. Toxicity testing using L. minor permitted us to evaluate the change in pesticide ecotoxicity. The plant growth inhibition involved excessive oxidative stress depending on the pesticide concentration, molecular structure, and degradation degree. Pesticide adsorption and/or conversion by ozonation on clay surfaces significantly reduced the toxicity towards L. minor plants, more particularly in the presence of Fe(II)-exchanged montmorillonite. The results showed a strong correlation between the pesticide toxicity towards L. minor and the level of reactive oxygen species, which was found to depend on the catalytic activity of the clay minerals, pesticide exposure time to ozone, and formation of harmful derivatives. These findings open promising prospects for developing a method to monitor pesticide ecotoxicity according to clay-containing host-media and exposure time to ambient factors.
Theoretical Assessment of the Ligand/Metal/Quadruplex Recognition in the Non-Canonical Nucleic Acids Structures
Authors: Kircheva Nikoleta , Dobrev Stefan , Petkova Vladislava , Bakalova Snezhana , Kaneti Jose , Angelova Silvia
Published: August 2023

Quadruplexes (GQs), peculiar DNA/RNA motifs concentrated in specific genomic regions, play a vital role in biological processes including telomere stability and, hence, represent promising targets for anticancer therapy. GQs are formed by folding guanine-rich sequences into square planar G-tetrads which stack onto one another. Metal cations, most often potassium, further stabilize the architecture by coordinating the lone electron pairs of the O atoms. The presence of additional nucleic acid bases, however, has been recently observed experimentally and contributes substantially to the structural heterogeneity of quadruplexes. Therefore, it is of paramount significance to understand the factors governing the underlying complex processes in these structures. The current study employs DFT calculations to model the interactions between metal cations (K+, Na+, Sr2+) and diverse tetrads composed of a guanine layer in combination with a guanine (G)-, adenine (A)-, cytosine (C)-, thymine (T)-, or uracil (U)-based tetrad layer. Moreover, the addition of 4-(3,4-dihydroisoquinolin-2-yl)-2-(quinolin-2-yl)quinazoline to the modeled quadruplexes as a possible mechanism of its well-exerted antitumor effect is assessed. The calculations imply that the metal cation competition and ligand complexation are influenced by the balance between electronic and implicit/explicit solvation effects, the composition of the tetrad layers, as well as by the solvent exposure to the surrounding environment expressed in terms of different dielectric constant values. The provided results significantly enhance our understanding of quadruplex diversity, ligand recognition, and the underlying mechanisms of stabilization at an atomic level.
Effect of Cd2+ Substitution on Structural–Magnetic and Dielectric Properties of Ni–Cu–Zn Spinel Ferrite Nanomaterials by Sol–Gel
Authors: Yang Hu , Yang Xingxing , Lin Jinpei , Yang Fang , He Yun , Lin Qing
Published: August 2023

CdxNi0.5−xCu0.2Zn0.3Fe2O4 (0 ≤ x ≤ 0.50) ferrite with a spinel structure was prepared using the sol–gel self-propagation method. The effects of Cd2+ doping on the structure, morphology, dielectric, and magnetic properties of Ni–Cu–Zn ferrite were examined using XRD, SEM, EDX, FTIR, MPMS, and dielectric tests. The cubic spinel structure was verified by XRD and FTIR analyses. The crystallite size and particle size information of the samples were obtained with XRD and SEM analysis. The sample particle size belonged to a class of nanoscale materials with a particle size range of 1–100 nm. The minor difference between the grain size and particle size indicated that the sample nanoparticles were composed of numerous microcrystals. The EDX spectra indicated that the samples contained all stoichiometric elements. MPMS was used to measure the hysteresis lines of the samples. According to the hysteresis line, the saturation magnetization intensity (Ms), coercivity (Hc), and magnetic moment (μB) of the sample increased and then decreased with the increase in cadmium concentration. The magnetization strength (Ms) is between 4–67 emu/g, and the coercivity (Hc) is between 9–46 Oe. The curves of the real part of the dielectric constant (ε′), the imaginary part of the dielectric constant (ε″), and the loss factor (tanδ) with frequency were measured in the frequency range 100 Hz–100 kHz by means of an impedance analyzer. The complex modulus spectrum was analyzed to understand the dynamics of the conduction process.