bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring the Mechanism of Strong-Pressure Fluctuation under Partial Load in the Turbine Mode of Pump Turbines for Hydro and Marine Power Storage
Authors: Lu Jiahao , Yan Wei , Tao Ran , Wang Zhengwei , Zhu Di
Published: May 2023

As a core component of pumped storage power plants for hydro and marine power storage, this paper investigates the mechanism of pressure pulsation fluctuations under different load conditions to improve the efficiency and operational stability of the storage units. The results of a combination of experiments and numerical simulations showed that the pressure pulsation fluctuations in the pump turbine under strong and weak loads were significantly different at different monitoring points. The three-dimensional flow lines diagram of the pump turbine unit from the CFD numerical simulation showed that the flow line of the pump turbine was relatively chaotic and the vortex existed under weak load conditions. Pressure clouds and flow lines in the cross-section and longitudinal section of the pump turbine are shown. Both showed high-pressure values and a chaotic flow line with a vortex under weak load conditions. To a certain extent, it revealed the pressure pulsation fluctuation mechanism of the pump turbine and provides some guidance for solving practical problems in engineering.
A Case Series of Continuous Theta Burst Stimulation Treatment for the Supplementary Motor Area Twice a Day in Patients with Obsessive-Compulsive Disorder: A Real World TMS Registry Study in Japan
Authors: Noda Yoshihiro , Fujii Kyoshiro , Tokura Fumi , Nakajima Shinichiro , Kitahata Ryosuke
Published: May 2023

Obsessive-compulsive disorder (OCD) is a psychiatric disorder characterized by patterns in which unwanted thoughts and fears are evoked as obsessions and furthermore, compulsive behaviors are provoked repeatedly, with a prevalence rate of 2% of the population. These obsessive-compulsive symptoms disrupt daily life and cause great distress to the individual. At present, OCD is treated with antidepressants, mainly selective serotonin reuptake inhibitors, and psychotherapy, including the exposure and response prevention method. However, these approaches may only show a certain level of efficacy, and approximately 50% of patients with OCD show treatment resistance. This situation has led to the research and development of neuromodulation therapies, including transcranial magnetic stimulation treatment, for OCD worldwide in recent years. In this case series, we retrospectively analyzed the TMS registry data of continuous theta burst stimulation (cTBS) therapy targeting the bilateral supplementary motor cortex for six patients with OCD whose obsessive-compulsive symptoms had not improved with pharmacotherapy. The results suggest that treatment with cTBS for the bilateral supplementary motor area may reduce obsessive-compulsive symptoms in patients with OCD, despite the limitations of an open-label preliminary case series. The present findings warrant further validation with a randomized, sham-controlled trial with a larger sample size in the future.
Association between Psychological, Biochemical and Personal Factors with the Inflammatory Marker High-Sensitive C Reactive Protein (Hs-CRP) in Mexican Healthy Population
Authors: Brambila-Tapia Aniel Jessica Leticia , Jacquez-Castañeda Ana Lilia , Carrillo-Delgadillo Laura Arely , Dávila-Flores Jessica Natalia , Macías-Espinoza Fabiola , Ramírez-De Los Santos Saúl , Gutiérrez-Hurtado Itzae Adonai
Published: May 2023

In the last decades, it has been shown that inflammatory processes play a role in the development of mental and physical problems; although some studies have researched the relationship between inflammation and psychological variables, the inclusion of biochemical variables as possible confounders has been limited. Therefore, the aim of this study was to determine whether psychological variables are associated with the inflammatory marker, highly sensitive CRP (hs-CRP), after controlling for personal and biochemical variables in the Mexican population. The study was performed at the University of Guadalajara facilities, during the second half of 2022. Healthy subjects were invited to participate in the study, which consisted of the measurement of personal, psychological, and biochemical variables. We included 172 participants, 92 (52.9%) of which were women; the median (range) of age of the whole sample was 22 (18–69) years old. In the bivariate analysis, significant positive correlations were observed between hs-CRP and body mass index (BMI) and waist/hip ratio (WHR) in both sexes, together with leukocytes, uric acid, low-density lipoprotein (LDL), triglycerides, and the liver enzymes gamma glutamyl transferase (GGT) and alkaline phosphatase (ALP). In the multivariate regression analysis of the global and men’s samples, anxiety was positively associated with hs-CRP, while depression and positive relations with others were negatively associated with hs-CRP. In conclusion, psychological variables influence inflammation mainly in men, and anxiety was the main contributor; in addition, positive relation with others is a variable that should be further explored as a psychological protector of inflammation in both sexes.
Evaluating the Applicability of Global LULC Products and an Author-Generated Phenology-Based Map for Regional Analysis: A Case Study in Ecuador’s Ecoregions
Authors: Villegas Rugel Gladys Maria , Ochoa Daniel , Menendez Jose Miguel , Van Coillie Frieke
Published: May 2023

An accurate and detailed understanding of land-use change affected by anthropogenic actions is key to environmental policy decision-making and implementation. Although global land cover products have been widely used to monitor and analyse land use/land cover (LULC) change, the feasibility of using these products at the regional level needs to be assessed due to the limitation and biases of generalised models from around the world. The main objective of the present study was to generate regional LULC maps of three target areas located in the main ecoregions of Ecuador at a resolution of 10 m using Google Earth Engine (GEE) cloud-based computing. Our approach is based on (1) Single Date Classification (SDC) that processes Sentinel-2 data into fuzzy rule-driven thematic classes, (2) rule refinement using Visible Infrared Imaging Radiometer Suite (VIIRS) data, and (3) phenology-based synthesis (PBS) classification that combines SDC into LULC based on the occurrence rule. Our results show that the three target areas were classified with an overall accuracy of over 80%. In addition, cross-comparison between the global land cover products and our LULC product was performed and we found discrepancies and inaccuracies in the global products due to the characteristics of the target areas that included a dynamic landscape. Our LULC product supplements existing official statistics and showcases the effectiveness of phenology-based mapping in managing land use by providing precise and timely data to support agricultural policies and ensure food security.
Numerical Simulation of the Lubricant-Solid Interface Using the Multigrid Method
Authors: Patel Ruchita , Khan Zulfiqar Ahmad , Bakolas Vasilios , Saeed Adil
Published: May 2023

Solid asperity interactions are common and inevitable under severe loading conditions for any lubricated contact. Heavy-duty machine components (gears, bearings, etc.) generally operate under Mixed Lubrication (ML), where uneven surface features contact each other when the generated fluid pressure is not enough to support the external load. The Reynolds equation is commonly used to simulate smooth lubricated contacts numerically. In rough lubricated interfaces where opposite surface asperities make contact, the Reynolds equation alone cannot accurately predict pressure using the traditional numerical simulation method. In this paper, lubrication–contact interface conditions (LCICs) have been implemented and extended to solve the multiple asperity contact problem using the full-multigrid approach. The developed novel algorithm has significantly accelerated the solution process and improved the accuracy and efficiency of pressure calculation for fluid–solid sub-interactions that can occur in ML regions. The results of the finite difference method (FDM) results have been compared with those of computational fluid dynamics (CFD) simulation to validate the newly developed model. Hence, the proposed optimized solution method will provide valuable insight to researchers and industry engineers interested in simulating the ML problem where the effect of the fluid–solid interface can be captured effectively to improve reliability in the calculation of the life expectancy of the lubricated parts.
Improvement of Hot Tearing Resistance of AZ91 Alloy with the Addition of Trace Ca
Authors: Xiang Hongchen , Liu Wenjun , Wang Qiang , Jiang Bin , Song Jiangfeng , Wu Hang , Feng Nan , Chai Linjiang
Published: May 2023

Hot tearing is the most common and serious casting defect that restricts the light weight and integration of magnesium alloy components. In the present study, trace Ca (0–1.0 wt.%) was added to improve the resistance of AZ91 alloy to hot tearing. The hot tearing susceptivity (HTS) of alloys was experimentally measured by a constraint rod casting method. The results indicate that the HTS presents a ν-shaped tendency with the increase in Ca content, and reaches its minimum value in AZ91–0.1Ca alloy. Ca is well dissolved into α-Mg matrix and Mg17Al12 phase at an addition not exceeding 0.1 wt.%. The solid-solution behavior of Ca increases eutectic content and its corresponding liquid film thickness, improves the strength of dendrites at high temperature, and thereby promotes the hot tearing resistance of the alloy. Al2Ca phases appear and aggregate at dendrite boundaries with further increases in Ca above 0.1 wt.%. The coarsened Al2Ca phase hinders the feeding channel and causes stress concentration during the solidification shrinkage, thereby deteriorating the hot tearing resistance of the alloy. These findings were further verified by fracture morphology observations and microscopic strain analysis near the fracture surface based on kernel average misorientation (KAM).
Microscopic and Mechanical Characterization of Co-Cr Dental Alloys Joined by the TIG Welding Process
Authors: Carek Andreja , Slokar Benić Ljerka , Bubalo Vatroslav , Kosović Nika
Published: May 2023

Due to their good mechanical and other properties, cobalt-chromium alloys (Co-Cr) are often used in prosthetic therapy. The metal structures of prosthetic works can be damaged and break, and depending on the extent of the damage, they can be re-joined. Tungsten inert gas welding (TIG) produces a high-quality weld with a composition very close to that of the base material. Therefore, in this work, six commercially available Co-Cr dental alloys were joined by TIG welding, and their mechanical properties were evaluated to determine the quality of the TIG process as a technology for joining metallic dental materials and the suitability of the Co-Cr alloys used for TIG welding. Microscopic observations were made for this purpose. Microhardness was measured using the Vickers method. The flexural strength was determined on a mechanical testing machine. The dynamic tests were carried out on a universal testing machine. The mechanical properties were determined for welded and non-welded specimens, and the results were statistically evaluated. The results show the correlation between the investigated mechanical properties and the process TIG. Indeed, characteristics of the welds have an effect on the measured properties. Considering all the results obtained, the TIG—welded I—BOND NF and Wisil M alloys showed the cleanest and most uniform weld and, accordingly, satisfactory mechanical properties, highlighting that they withstood the maximum number of cycles under dynamic load.
Multi-Response Optimization of High-Performance Low-pH Grouting Materials by Using Taguchi-Based Grey Relational Analysis
Authors: Ren Zengzeng , Zhao Weiquan , Wang Ju , Zhang Jinjie , Chen Liang , Li Yonghui
Published: May 2023

The most accepted approach to sealing in high-level radioactive waste repositories (HLRWs) is to develop a low-pH grouting material with a pH of the pore solution of less than 11. Currently, the most widely used binary low-pH grouting material is MCSF64, which comprises 60% microfine cement (MC) and 40% silica fume (SF). In this study, a high-performance MCSF64-based grouting material was developed by incorporating naphthalene superplasticizer (NSP), aluminum sulfate (AS), and united expansion agent (UEA) to enhance the slurry’s shear strength, compressive strength, and hydration process. Orthogonal experiments were conducted to measure the flow time, yield stress, plastic viscosity, initial setting time, shear strength, and compressive strength of the MCSF64-based slurry, and the optimal mix proportion was determined using the Taguchi–Grey relational analysis method. The pH variation of the pore solution, shrinkage/expansion, and hydration products of the optimal hardened slurry were evaluated using simplified ex-situ leaching (S-ESL), a length comparometer, and scanning electron microscopy (SEM), respectively. The results demonstrate that the Bingham model effectively predicted the rheological properties of the MCSF64-based slurry. The optimum ratio for the MCSF64-based slurry was water/binder (W/B) ratio of 1.4, and the contents of NSP, AS and UEA by mass of binder were 1.9%, 3.6% and 4.8%, respectively. The optimal mix exhibited a pH value below 11 after curing for 120 days. The addition of AS and UEA facilitated hydration, shortened the initial setting time, improved early shear strength, and enhanced the expansion ability of the optimal mix under water curing conditions.
Development of an Instantaneous Loading Impact Test System for Containment of a Nuclear Power Plant during Aircraft Impact on Steel Bar Joints
Authors: Zhu Wanxu , Liang Shiyuan , Jia Kefei , Shen Quanxi , Wu Dongwen
Published: May 2023

As major projects such as nuclear power plants continuously increase, it is inevitable that loopholes will arise in safety precautions. Airplane anchoring structures, comprising steel joints and acting as a key component of such a major project, directly affect the safety of the project due to their resistance to the instant impact of an airplane. Existing impact testing machines have the limitations of being unable to balance impact velocity and impact force, as well as having inadequate control of impact velocity; they cannot meet the requirements of impact testing for steel mechanical connections in nuclear power plants. This paper discusses the hydraulic-based principle of the impact test system, adopts the hydraulic control mode, and uses the accumulator as the power source to develop an instant loading test system suitable for the entire series of steel joints and small-scale cable impact tests. The system is equipped with a 2000 kN static-pressure-supported high-speed servo linear actuator, a 2 × 22 kW oil pump motor group, a 2.2 kW high-pressure oil pump motor group, and a 9000 L/min nitrogen-charging accumulator group, which can test the impact of large-tonnage instant tensile loading. The maximum impact force of the system is 2000 kN, and the maximum impact rate is 1.5 m/s. Through the impact testing of mechanical connecting components using the developed impact test system, it was found that the strain rate of the specimen before failure was not less than 1 s−1, meeting the requirements of the technical specifications for nuclear power plants. By adjusting the working pressure of the accumulator group, the impact rate could be controlled effectively, thus providing a strong experimental platform for research in the field of engineering for preventing emergencies.
A Selective Review of Ceramic, Glass and Glass–Ceramic Protective Coatings: General Properties and Specific Characteristics for Solar Cell Applications
Authors: Fraser Rebekah , Girtan Mihaela
Published: May 2023

A review on ceramics, glasses and glass–ceramics as thin film protective coatings for solar cells is given. The different preparation techniques and the physical and chemical properties are presented in a comparative way. This study is useful for technologies involving solar cells and solar panel cell development at the industrial scale, because protective coatings and encapsulation play a major role in increasing the lifetime of solar panels and environmental protection. The aim of this review article is to give a summary of existing ceramic, glass, and glass–ceramic protective coatings and how they apply to solar cell technology: silicon, organic or perovskite cells. Moreover, some of these ceramic, glass or glass–ceramic layers were found to have dual functionality, such as providing anti-reflectivity or scratch resistance to give a two-fold improvement to the lifetime and efficiency of the solar cell.
StressLife: A Short-Time Approach for the Determination of a Trend S-N Curve in and beyond the HCF Regime for the Steels 20MnMoNi5-5 and SAE 1045
Authors: Weber Fabian , Koziol Janina , Starke Peter
Published: May 2023

Within the scope of this research, a new short-time procedure designated as StressLifeHCF was developed. Through a combination of classic fatigue testing and non-destructive monitoring of the material response due to cyclic loading, a process-oriented fatigue life determination can be carried out. A total of two load increases and two constant amplitude tests are required for this procedure. By using data from non-destructive measurements, the parameters of the elastic approach according to Basquin and the plastic approach according to Manson–Coffin were determined and combined within the StressLifeHCF calculation. Furthermore, two additional variations of the StressLifeHCF method were developed in order to be able to accurately describe the S-N curve over a wider range. The main focus of this research was 20MnMoNi5-5 steel, which is a ferritic-bainitic steel (1.6310). This steel is widely used for spraylines in German nuclear power plants. In order to validate the findings, tests were also performed on an SAE 1045 steel (1.1191).
Investigation of Oxidation Homogeneity in Asphalt Puck after Simulation of Long-Term Aging (Pressure Aging Vessel)
Authors: Bruneau Lorris , Tisse Séverine , Michon Laurent , Cardinael Pascal
Published: May 2023

For decades, it has been known that the creation of oxygenated functional groups, especially carbonyl and sulfoxide, is among the main causes of chemical aging and degradation of asphalt. However, is the oxidation of a bitumen homogeneous? The focus of this paper was to follow the oxidation phenomena through an asphalt puck during a pressure aging vessel (PAV) test. According to the literature, the asphalt oxidation process that leads to the creation of oxygenated functions can be divided into the following successive main steps: the absorption of oxygen in asphalt at the air/asphalt interface, diffusion into the matrix, and reaction with asphalt molecules. To study the PAV oxidation process, the creation of carbonyl and sulfoxide functional groups in three asphalts were investigated after various aging protocols by Fourier transform infrared spectroscopy (FTIR). From these experiments performed on different layers of asphalt puck, it was observed that PAV aging resulted in a nonhomogeneous oxidation level inside the entire matrix. Compared to the upper surface, the lower section exhibited carbonyl and sulfoxide indices 70% and 33% lower, respectively. Moreover, the difference in the oxidation level between the top and bottom surfaces increased when the thickness and viscosity of the asphalt sample increased.
Engineering Applications of Artificial Intelligence in Mechanical Design and Optimization
Authors: Jenis Jozef , Ondriga Jozef , Hrcek Slavomir , Brumercik Frantisek , Cuchor Matus , Sadovsky Erik
Published: May 2023

This study offers a complete analysis of the use of deep learning or machine learning, as well as precise recommendations on how these methods could be used in the creation of machine components and nodes. The examples in this thesis are intended to identify areas in mechanical design and optimization where this technique could be widely applied in the future, benefiting society and advancing the current state of modern mechanical engineering. The review begins with a discussion on the workings of artificial intelligence, machine learning, and deep learning. Different techniques, classifications, and even comparisons of each method are described in detail. The most common programming languages, frameworks, and software used in mechanical engineering for this problem are gradually introduced. Input data formats and the most common datasets that are suitable for the field of machine learning in mechanical design and optimization are also discussed. The second half of the review describes the current use of machine learning in several areas of mechanical design and optimization, using specific examples that have been investigated by researchers from around the world. Further research directions on the use of machine learning and neural networks in the fields of mechanical design and optimization are discussed.
Rethinking the Role of Organizational Reflex in Maintaining a Company’s Sustainability
Authors: Vaitkevicius Sigitas , Purvinis Ojaras , Sakalauskas Leonidas , Papsiene Palmira
Published: May 2023

The organizational reflex in relation to the company is considered to be an instinctive reaction of its employees to an external stimulus that has arisen or, in other words, the ability of the employee to spontaneously generate a competitive response of the company based on the information received from the global environment. It is an intentional algorithm that enables employees to know how and when to react as quickly as possible, according to the signal from the global environment received, within the limits of their area of expertise. This response phenomenon comes forth in the context of the functioning of a sustainable organization and highlights the coherence of the performance of a human resource. In order to maintain its competitiveness, each organization learns to react to the ongoing changes in the dynamic environment as quickly as possible and, in this process, develops action algorithms similar to human reflexes in structure. Modern science makes a great contribution to the longevity of the company by creating activity models for the organization and performing simulations in the digital space. In this paper, the simulation model of a company’s competitive human resource response to global changes, which is used for the description of organizational reflex, is present. The model reflects the human reflex arc in a company’s decision-making process, whose effectiveness depends on the coherence of its human resources and its ability to sustain an effective organizational reflex. The purpose of the developed model is to simulate the employee’s response to the signals incoming from the global environment and to describe the development process of the organizational reflex that is leading to the longevity of the company and the sustainability of its market leadership.
Adaptive Enhanced Detection Network for Low Illumination Object Detection
Authors: Wei Hanting , Yu Bo , Wang Wei , Zhang Chenghong
Published: May 2023

Any small environmental changes in the driving environment of a traffic vehicle can become a risk factor directly leading to major safety incidents. Therefore, it is necessary to assist drivers in automatically detecting risk factors during the driving process using algorithms. However, besides making it more difficult for drivers to judge environmental changes, the performance of automatic detection networks in low illumination scenarios can also be greatly affected and cannot be used directly. In this paper, we propose a risk factor detection model based on deep learning in low illumination scenarios and test the optimization of low illumination image enhancement problems. The overall structure of this model includes dual discriminators, encoder–decoders, etc. The model consists of two main stages. In the first stage, the input low illumination scene image is adaptively converted into a standard illumination image through a lighting conversion module. In the second stage, the converted standard illumination image is automatically assessed for risk factors. The experiments show that the detection network can overcome the impact of low lighting and has high detection accuracy.
Mean-Square Stability of Uncertain Delayed Stochastic Systems Driven by G-Brownian Motion
Authors: Ma Zhengqi , Yuan Shoucheng , Meng Kexin , Mei Shuli
Published: May 2023

This paper investigates the mean-square stability of uncertain time-delay stochastic systems driven by G-Brownian motion, which are commonly referred to as G-SDDEs. To derive a new set of sufficient stability conditions, we employ the linear matrix inequality (LMI) method and construct a Lyapunov–Krasovskii function under the constraint of uncertainty bounds. The resulting sufficient condition does not require any specific assumptions on the G-function, making it more practical. Additionally, we provide numerical examples to demonstrate the validity and effectiveness of the proposed approach.
Cross-Diffusion-Induced Turing Instability in a Two-Prey One-Predator System
Authors: Yu Ying , Chen Yahui , Zhou You
Published: May 2023

This paper focuses on a strongly coupled specific ecological system consisting of two prey species and one predator. We explore a unique positive equilibrium solution of the system that is globally asymptotically stable. Additionally, we show that this equilibrium solution remains locally linearly stable, even in the presence of diffusion. This means that the system does not follow classical Turing instability. However, it becomes linearly unstable only when cross-diffusion also plays a role in the system, which is called a cross-diffusion-induced instability. The corresponding numerical simulations are also demonstrated and we obtain the spatial patterns.
Perturbed Skew Diffusion Processes
Authors: Tian Yingxu , Zhang Haoyan
Published: May 2023

This work investigates whether there uniquely exists a solution to the perturbed skew diffusion process. We construct the solution by iteration and divide the whole time interval into parts on which we disperse the perturbed skew diffusion process into two tractable portions, one for perturbed diffusion process, the other for skew diffusion process. After this disposition, we only focus on the process in each time interval. Noticing the continuity on every time interval boundaries generalized by a sequence of stopping times, we acquire the main result of this paper as well as a time change for the perturbed skew process.
Effectiveness of Pelvic Floor Muscle Training on Quality of Life in Women with Urinary Incontinence: A Systematic Review and Meta-Analysis
Authors: Curillo-Aguirre César Adrián , Gea-Izquierdo Enrique
Published: May 2023

Background and Objectives: Urinary incontinence (UI) is a condition that is more common in women than men and has an increasing prevalence with age. It provides a range of psychological and physical burdens that negatively affect the patient’s quality of life (QoL). However, the economic burden for the healthcare system is being augmented due to the increasing life expectancy of the population. This article aims to identify the effectiveness of pelvic floor muscle training (PFMT) on the QoL in women with UI. Materials and Methods: A systematic review and meta-analysis were conducted in the PubMed, EMBASE, ProQuest medicine, Cochrane Library, and Google Scholar databases. The terms selected according to components of PICOS were women with urinary incontinence, pelvic floor muscle training, watchful or other types of therapies, quality of life, randomized controlled trials, and interventional or observational studies. The articles included were those published between November 2018 and November 2022. Ten articles were found for the systematic review and eight for the meta-analysis. Results: The QoL moderately increased when PFMT was used on women with UI, the results indicating an overall small effect on the QoL across the controlled studies and a moderate effect on the QoL across the one-group pre-post-studies. Conclusions: Specific QoL domains, such as social activities and general health, also demonstrated benefits from PFMT interventions. This study confirmed the effectiveness of PFMT on the QoL in women with UI, mainly for patients with stress urinary incontinence.
On the Use of Permselectivity to Describe the Selective Transfer of Organic Acids in Electrodialysis
Authors: Caveriviere Robin , Galier Sylvain , Roux-de Balmann Hélène
Published: May 2023

The increasing number of investigations on the use of electrodialysis (ED) in bio-refinery requires a better understanding and tools to evaluate and describe the transfer of charged organic solutes. This study focuses, as an example, on the selective transfer of acetate, butyrate, and chloride (used as a reference), characterized by using permselectivity. It is shown that permselectivity between two anions does not depend on the total ion concentration, neither on the ion proportions, current intensity, or time nor on the presence of an additional compound. Therefore, it is demonstrated that permselectivity can be used to model the evolution of the stream composition during ED, even at high demineralization rates. Indeed, a very good agreement is found between experimental and calculated values. This study and the application of permselectivity as a tool, as developed in this paper, could be highly valuable for a wide range of applications in electrodialysis.
Untargeted Metabolomic Analysis of Sjögren–Larsson Syndrome Reveals a Distinctive Pattern of Multiple Disrupted Biochemical Pathways
Authors: Dai Hongying Daisy , Qiu Fang , Jackson Kimberly , Fruttiger Marcus , Rizzo William B.
Published: May 2023

Sjögren–Larsson syndrome (SLS) is a rare inherited neurocutaneous disease characterized by ichthyosis, spastic diplegia or tetraplegia, intellectual disability and a distinctive retinopathy. SLS is caused by bi-allelic mutations in ALDH3A2, which codes for fatty aldehyde dehydrogenase (FALDH) and results in abnormal lipid metabolism. The biochemical abnormalities in SLS are not completely known, and the pathogenic mechanisms leading to symptoms are still unclear. To search for pathways that are perturbed in SLS, we performed untargeted metabolomic screening in 20 SLS subjects along with age- and sex-matched controls. Of 823 identified metabolites in plasma, 121 (14.7%) quantitatively differed in the overall SLS cohort from controls; 77 metabolites were decreased and 44 increased. Pathway analysis pointed to disrupted metabolism of sphingolipids, sterols, bile acids, glycogen, purines and certain amino acids such as tryptophan, aspartate and phenylalanine. Random forest analysis identified a unique metabolomic profile that had a predictive accuracy of 100% for discriminating SLS from controls. These results provide new insight into the abnormal biochemical pathways that likely contribute to disease in SLS and may constitute a biomarker panel for diagnosis and future therapeutic studies.
5-Fluorouracil-Encapsulated Films Using Exopolysaccharides from a Thermophilic Bacterium Geobacillus sp. WSUCF1 for Topical Drug Delivery
Authors: Laubach Joseph M. , Sani Rajesh K.
Published: May 2023

Bacteria are capable of producing a specific type of biopolymer, termed exopolysaccharides (EPSs). EPSs from thermophile Geobacillus sp. strain WSUCF1 specifically can be assembled using cost-effective lignocellulosic biomass as the primary carbon substrate in lieu of traditional sugars. 5-fluorouracil (5-FU) is an FDA-approved, versatile chemotherapeutic that has yielded high efficacy against colon, rectum, and breast cancers. The present study investigates the feasibility of a 5% 5-fluorouracil film using thermophilic exopolysaccharides as the foundation in conjunction with a simple self-forming method. The drug-loaded film formulation was seen to be highly effective against A375 human malignant melanoma at its current concentration with viability of A375 dropping to 12% after six hours of treatment. A drug release profile revealed a slight burst release before it settled into an extended and maintained release of 5-FU. These initial findings provide evidence for the versatility of thermophilic exopolysaccharides produced from lignocellulosic biomass to act as a chemotherapeutic-delivering device and expand the overall applications of extremophilic EPSs.
Boosting the Performance of Perovskite Solar Cells through Systematic Investigation of the Annealing Effect of E-Beam Evaporated TiO2
Authors: Xue Tao , Chen Dandan , Li Ting , Chou Xingxing , Wang Xiao , Tang Zhenyu , Zhang Fanghui , Huang Jin , Guo Kunping , Takaloo Ashkan Vakilipour
Published: May 2023

Electron transport layer (ETL) plays an undeniable role in improving the performance of n-i-p planar perovskite solar cells (PSCs). Titanium dioxide (TiO2) is known as a promising ETL material for perovskite solar cell. In this work, the effect of annealing temperature on optical, electrical, and surface morphology of the electron-beam (EB)-evaporated TiO2 ETL, and consequently on the performance of perovskite solar cell, was investigated. It was found that annealing treatment at an optimized temperature of 480 °C considerably improved the surface smoothness, density of grain boundaries, and carrier mobility of TiO2 film, which resulted in nearly 10-fold improvement in power conversion efficiency (11.16%) in comparison with the unannealed device (1.08%). The improvement in performance of the optimized PSC is attributed to the acceleration of charge carrier extraction, as well as suppression of the recombination at the ETL/Perovskite interface.
Detrital Zircon LA-ICP-MS U-Pb Ages of the North Liaohe Group from the Lianshanguan Area, NE China: Implications for the Tectonic Evolution of the Paleoproterozoic Jiao-Liao-Ji Belt
Authors: Gao Jinhui , Li Weimin , Liu Yongjiang , Zhao Yingli , Liu Tongjun , Wen Quanbo
Published: May 2023

The Liaohe Group, which is a significant lithostratigraphic unit within the Paleoproterozoic Jiao-Liao-Ji Belt situated between the Longgang and Liaonan-Nangrim blocks, comprises the Langzishan, Li’eryu, Gaojiayu, Dashiqiao, and Gaixian formations, which are characterized mainly by a clastic-rich sequence with an interlayered bimodal-volcanic sequence, carbonate-rich sequence, and (meta-)pelite-rich sequence. Currently, the tectonic background and evolution of the Liaohe Group remain contentious. Based on the study of detrital zircon geochronology and the zircon trace element characteristics in the Langzishan and Li’eryu formations in the North Liaohe Group in the Lianshanguan area, NE China, this paper reveals the formations’ provenances, depositional ages, and relationships with Paleoproterozoic granitoids (the Liao-Ji granites). The present results, in conjunction with previous studies, indicate that the depositional age of the Langzishan Formation is 2136 Ma and that of the Li’eryu Formation is 1974 Ma. The provenances of the Langzishan Formation and the Li’eryu Formation are mainly characterized by Neoarchean-to-early-Paleoproterozoic basement rocks (~2.6–2.4 Ga) and the Liao-Ji granites (~2.2–2.0 Ga), respectively. Moreover, the coeval mafic and metasedimentary rocks of the Liaohe Group exhibit characteristics of an extensional environment, which is represented by the tectonic setting of a back-arc basin. Notably, the Upper Langzishan Formation records a prominent shift in sedimentary environment from a passive continental margin to an active continental margin. In terms of the tectonic evolution of the North Liaohe Group and the Jiao-Liao-Ji Belt, our proposed model suggests that the Archean basement rocks in the northern part of the continental block, along with a limited contribution from the Paleoproterozoic Liao-Ji granites, served as the primary sources for the Langzishan Formation. Subsequently, the rapid deposition of the Li’eryu Formation was influenced by intense magmatism and subsequent erosion of the subduction-related magmatic arc (the Liao-Ji granites) within a back-arc basin environment. Lastly, the deposition of clastic materials from the Longgang blocks and the Liao-Ji granites resulted in the formation of the Gaojiayu, Dashiqiao, and Gaixian formations.
Simulation of Solvent Extraction Circuits for the Separation of Rare Earth Elements
Authors: Turgeon Keven , Boulanger Jean-François , Bazin Claude
Published: May 2023

The separation of Rare Earth Elements (REEs) is an important step in the valorization of REE ore and aims at producing individual rare earth compounds for the market. The separation is carried out industrially by solvent extraction (SX) using interconnected circuits consisting of cascades of mixer-settlers. The design of a REE separation circuit implies the selection of the operating conditions and of the number of mixer-settlers required to achieve a target degree of purity for the separated elements. This design work is either carried out by piloting a circuit or using a mathematical simulation. Independent of the method, the world expertise in this area is limited. This paper describes a simulation method requiring a minimum of calibration effort, which can be used to design a complete REE separation plant. The simulation enables assessment of the effect of the number of mixer-settlers per extraction, the scrubbing and stripping stage, as well as the pH of the aqueous solution and organic-phase contents of free and loaded extractant on the purity of the separated REEs. The simulation tool presented here has been developed from a fundamental analysis of the chemical reactions involved in the solvent extraction process. Unlike most of the simulation methods documented in the literature, the method requires no empirical calibration. The proposed method is validated using data from laboratory batch tests and with published data from continuous pilot and industrial REE separation circuits. The application of the simulation tool is illustrated with the planning of the test conditions for a forthcoming pilot test work and with the simulation of a 9-REE product SX separation plant.
Photosensitive Dye as an Ideal Peroxymonosulfate Activator for Efficient Self-Degradation: A Novel Idea of Using Waste to Treat Waste
Authors: Zhang Zhiyao , Li Zhaolin , Bai Xue , Shi Juan , Hu Min , Chai Jin , Li Keqian , Jin Pengkang
Published: May 2023

Commonly used peroxydisulfate (PS) or peroxymonosulfate (PMS) activation methods have been limited in their practical application due to certain drawbacks, such as high cost, high energy consumption and secondary pollution. In this study, a catalyst-free alizarin green (AG) self-activating PMS catalytic system was constructed based on photosensitization properties of dye, which ultimately achieved efficient degradation of the dye activator, also the target pollutant. Here, 52.5% of the 100 mL mixture of 10 mg/L AG decomposed within 60 min with 1 mM PMS under visible-light irradiation, thereby showing a strong pH adaptation. Mechanism of AG self-activating PMS was revealed that the photo-excited AG can effectively transfer photo-induced electrons to PMS for its activation, which generates reactive oxidizing species dominated by singlet oxygen (1O2), and supplemented by hydroxyl radical (•OH), superoxide radical (O2•−) and sulfate radical (SO4•−) to realize the efficient self-degradation of the dye pollutants. Moreover, such self-catalytic system operated well under natural sunlight irradiation, indicating the great application potential in the actual wastewater treatment. Herein, photosensitive dye acted as an ideal PMS activator realizing its efficient self-degradation, which provides a novel idea of “using waste to treat waste” for developing wastewater treatment process in a high-efficiency and low-consumption way.
Investigation of Antimicrobial Effects of Polydopamine-Based Composite Coatings
Authors: Batul Rahila , Bhave Mrinal , Yu Aimin
Published: May 2023

Herein, polydopamine (PDA)-based antimicrobial coatings loaded with silver nanoparticles (Ag NPs) and gentamicin were designed and prepared on glass slides using two different approaches. To our knowledge, this study was performed for the first time with the aim to compare these methods (viz., in situ loading and physical adsorption method) regarding the loading and release behavior of payloads. In one method, gentamicin was in situ loaded on PDA-coated substrates during PDA polymerization followed by Ag NPs immobilization (named as Ag@Gen/PDA); for the second method, Ag NPs and gentamicin were simultaneously loaded onto PDA via physical adsorption by immersing pre-formed PDA coatings into a mixed solution of Ag NPs and gentamicin (named as Ag/Gen@PDA). The loading and release characteristics of these antimicrobial coatings were compared, and both gave variable outcomes. The in situ loading method consequently provided a relatively slow release of loaded antimicrobials, i.e., approx. 46% for Ag@Gen/PDA as compared to 92% from physically adsorbed Ag/GenPDA in an immersion period of 30 days. A similar trend was observed for gentamicin release, i.e., ~0.006 µg/mL from Ag@Gen/PDA and 0.02 µg/mL from Ag/Gen@PDA each day. The slower antimicrobial release from Ag@Gen/PDA coatings would ultimately provide an effective long-term antimicrobial property as compared to Ag/Gen@PDA. Finally, the synergistic antimicrobial activities of these composite coatings were assessed against two microbial species, namely, Staphylococcus aureus and Escherichia coli, hence providing evidence in the prevention of bacterial colonization.
Scope and Limitations of Exploiting the Ability of the Chemosensitizer NV716 to Enhance the Activity of Tetracycline Derivatives against Pseudomonas aeruginosa
Authors: Draveny Margot , Rose Clémence , Pinet Alexis , Ferrié Laurent , Figadère Bruno , Brunel Jean-Michel , Masi Muriel
Published: May 2023

The spread of antibiotic resistance is an urgent threat to global health that requires new therapeutic approaches. Treatments for pathogenic Gram-negative bacteria are particularly challenging to identify due to the robust OM permeability barrier in these organisms. One strategy is to use antibiotic adjuvants, a class of drugs that have no significant antibacterial activity on their own but can act synergistically with certain antibiotics. Previous studies described the discovery and development of polyaminoisoprenyl molecules as antibiotic adjuvants with an OM effect. In particular, the compound NV716 has been shown to sensitize Pseudomonas aeruginosa to tetracycline antibiotics such as doxycycline. Here, we sought to explore the disruption of OM to sensitize P. aeruginosa to otherwise inactive antimicrobials using a series of tetracycline derivatives in the presence of NV716. We found that OM disruption expands the hydrophobicity threshold consistent with antibacterial activity to include hydrophobic molecules, thereby altering permeation rules in Gram-negative bacteria.
Rational Engineering of (S)-Norcoclaurine Synthase for Efficient Benzylisoquinoline Alkaloids Biosynthesis
Authors: De Sousa João P. M. , Oliveira Nuno C. S. A. , Fernandes Pedro A.
Published: May 2023

(S)-Norcoclaurine is synthesized in vivo through a metabolic pathway that ends with (S)-norcoclaurine synthase (NCS). The former constitutes the scaffold for the biosynthesis of all benzylisoquinoline alkaloids (BIAs), including many drugs such as the opiates morphine and codeine and the semi-synthetic opioids oxycodone, hydrocodone, and hydromorphone. Unfortunately, the only source of complex BIAs is the opium poppy, leaving the drug supply dependent on poppy crops. Therefore, the bioproduction of (S)-norcoclaurine in heterologous hosts, such as bacteria or yeast, is an intense area of research nowadays. The efficiency of (S)-norcoclaurine biosynthesis is strongly dependent on the catalytic efficiency of NCS. Therefore, we identified vital NCS rate-enhancing mutations through the rational transition-state macrodipole stabilization method at the Quantum Mechanics/Molecular Mechanics (QM/MM) level. The results are a step forward for obtaining NCS variants able to biosynthesize (S)-norcoclaurine on a large scale.
Validation and Simultaneous Monitoring of 311 Pesticide Residues in Loamy Sand Agricultural Soils by LC-MS/MS and GC-MS/MS, Combined with QuEChERS-Based Extraction
Authors: Tsiantas Petros , Bempelou Eleftheria , Doula Maria , Karasali Helen
Published: May 2023

Soil can be contaminated by pesticide residues through agricultural practices, by direct application or through spray-drift in cultivations. The dissipation of those chemicals in the soil may pose risks to the environment and human health. A simple and sensitive multi-residue analytical method was optimized and validated for the simultaneous determination of 311 active substances of pesticides in agricultural soils. The method involves sample preparation with QuEChERS-based extraction, and determination of the analytes with a combination of GC-MS/MS and LC-MS/MS techniques. Calibration plots were linear for both detectors over the range of five concentration levels, using matrix-matched calibration standards. The obtained recoveries from fortified-soil samples ranged from 70 to 119% and from 72.6 to 119% for GC-MS/MS and LC-MS/MS, respectively, while precision values were <20% in all cases. As regards the matrix effect (ME), signal suppression was observed in the liquid chromatography (LC)-amenable compounds, which was further estimated to be negligible. The gas chromatography (GC)-amenable compounds showed enhancement in the chromatographic response estimated as medium or strong ME. The calibrated limit of quantification (LOQ) value was 0.01 μg g−1 dry weight for most of the analytes, while the corresponding calculated limit of determination (LOD) value was 0.003 μg g−1 d.w. The proposed method was subsequently applied to agricultural soils from Greece, and positive determinations were obtained, among which were non-authorized compounds. The results indicate that the developed multi-residue method is fit for the purpose of analyzing low levels of pesticides in soil, according to EU requirements.
Effect of Cyclohexane on the Combustion Characteristics of Multi-Component Gasoline Surrogate Fuels
Authors: Rao Shunlu , Zheng Zhaolei , Yang Chao
Published: May 2023

It has been discovered that there is a dynamic coupling between cycloalkanes and aromatics, which affects the number and types of radicals, thereby controlling the ignition and combustion of fuels. Therefore, it is necessary to analyze the effects of cyclohexane production in multicomponent gasoline surrogate fuels containing cyclohexane. In this study, a five-component gasoline surrogate fuel kinetic model containing cyclohexane was first verified. Then, the effect of cyclohexane addition on the ignition and combustion performance of the surrogate fuel was analyzed. This study shows that the five-component model exhibits good predictive performance for some real gasoline. Meanwhile, the addition of cyclohexane decreases the ignition-delay time of the fuel in the low and high temperature bands, which is caused by the early oxidation and decomposition of cyclohexane molecules, generating more OH radicals; in the medium temperature band, the isomerization and decomposition reactions of cyclohexane oxide cC6H12O2 dominate the temperature sensitivity of the ignition delay, affecting the small molecule reactions that promote the generation of reactive radicals such as OH, thus inhibiting the negative temperature coefficient behavior of the surrogate fuel. The laminar flame speed of the surrogate fuels increased with the increase in the proportion of cyclohexane. This is due to the fact that the laminar flame speed of cyclohexane is higher than that of chain and aromatic hydrocarbons, and the addition of cyclohexane dilutes the ratio of chain and aromatic hydrocarbons in the mixture. In addition, engine simulation studies have shown that at higher engine speeds, the five-component surrogate fuel containing cyclohexane requires lower intake-gas temperatures to achieve positive ignition and are closer to the in-cylinder ignition of real gasoline.