bluuebunny/crossref_metadata_2025 huggingface dataset:
Fire Properties of Paper Sheets Made of Cellulose Fibers Treated with Various Retardants
Authors: Szubert Zuzanna , Mazela Bartłomiej , Tomkowiak Karolina , Grześkowiak Wojciech
Published: June 2024

This article presents the results of flame-retardancy tests conducted on cellulose sheets produced using a Rapid Köthen apparatus treated with retardants. The agents used were potassium carbonate (PC) K2CO3 (concentrations of 20; 33.3; and 50% wt/wt), monoammonium phosphate (MAP) NH4H2PO4 (concentrations of 35% wt/wt), diammonium phosphate (DAP) (NH4)2HPO4 (concentrations of 42.9% wt/wt), and bisguanidal phosphate (FOS) C2H10N6 (concentrations of 22.5% wt/wt). The agents were used to improve Kraft cellulose-based sheets’ flame-retardant properties and compare their performances. As part of the study, the flammability of the materials was determined by the following methods: an oxygen index (OI) test, a mass loss calorimeter (MLC) test, and a mini fire tube (MFT) test. All formulations showed an increase in flame retardancy compared to the control test. All protected samples were non-flammable for OI determinations, and DAP-protected samples showed the highest OI index. For the MLC test, DAP-protected and MAP-protected samples showed the best heat-release rate (HRR), total heat release (THR), and average heat-release rate (ARHE) (samples did not ignite for 600 s). In the MFT test, all treated samples had comparably reduced weight loss. The best parameter was achieved for MAP and DAP (15% weight loss).
Optimized Adsorption–Catalytic Conversion for Lithium Polysulfides by Constructing Bimetallic Compounds for Lithium–Sulfur Batteries
Authors: Chen Liping , Wang Runhua , Li Nan , Bai Yang , Zhou Yimo , Wang Juan
Published: June 2024

Although lithium–sulfur batteries possess the advantage of high theoretical specific capacity, the inevitable shuttle effect of lithium polysulfides is still a difficult problem restricting its application. The design of highly active catalysts to promote the redox reaction during charge–discharge and thus reduce the existence time of lithium polysulfides in the electrolyte is the mainstream solution at present. In particular, bimetallic compounds can provide more active sites and exhibit better catalytic properties than single-component metal compounds by regulating the electronic structure of the catalysts. In this work, bimetallic compounds-nitrogen-doped carbon nanotubes (NiCo)Se2-NCNT and (CuCo)Se2-NCNT are designed by introducing Ni and Cu into CoSe2, respectively. The (CuCo)Se2-NCNT delivers an optimized adsorption–catalytic conversion for lithium polysulfide, benefitting from adjusted electron structure with downshifted d-band center and increased electron fill number of Co in (CuCo)Se2 compared with that of (NiCo)Se2. This endows (CuCo)Se2 moderate adsorption strength for lithium polysulfides and better catalytic properties for their conversion. As a result, the lithium–sulfur batteries with (CuCo)Se2-NCNT achieve a high specific capacity of 1051.06 mAh g−1 at 1C and an enhanced rate property with a specific capacity of 838.27 mAh g−1 at 4C. The work provides meaningful insights into the design of bimetallic compounds as catalysts for lithium–sulfur batteries.
Enhanced Optical Limiting of Gold Nanoparticles/Porous Carbon Nanocomposites
Authors: Gao Bo , Zhao Xuhui , Yang Lijiao , Yan Lihe , Lin Tao , Si Jinhai
Published: June 2024

With the wide application of laser weapons, the requirements of laser protection technology are becoming more and more strict. Therefore, it is important to find ideal optical limiting (OL) materials to protect human eyes and detectors. In this work, the nonlinear optical responses of gold nanoparticles/porous carbon (Au NPs/PC) nanocomposites prepared by the reduction method were studied using the nanosecond Z-scan technique. Compared with porous carbon, the Au NPs/PC nanocomposites show a lower damage threshold, a bigger optical limiting index and a wider absorption spectrum. The interaction between gold nanoparticles and porous carbon enhances the nonlinear scattering effect of suspended bubbles. These results indicate that Au NPs composites have potential applications in the protection of human eyes and detectors.
The Influence of Using Steel Tapes and Composite Materials on Reinforcing Hot-Rolled Steel Profiles
Authors: Szewczak Ilona , Rozylo Patryk
Published: June 2024

Steel structure designers frequently encounter the need to reinforce hot-rolled compressed steel elements. This is particularly common in the case of compressed truss bars in steel truss girders. Typically, reinforcement is designed using bars or flat bars welded to the compressed element. However, welding technology is not always feasible in existing and operational steel halls due to fire safety concerns. To address this challenge, researchers investigated alternative reinforcement methods using bonded steel and CFRPs (carbon fiber-reinforced polymers/plastics) tapes. Laboratory tests and numerical analyses were conducted. Eleven 1.5 m long specimens made of 50 × 50 × 4 angle iron from S235 steel were subjected to axial compression testing. The test samples included three unreinforced samples, three samples reinforced with steel tape bonded using SikaDur-30 adhesive, and five samples reinforced with CFRP tape (SikaDur-30 adhesive was used for bonding in three cases, and 3M VHB GPH-160GF tape in two cases). The research conducted indicates that reinforcement using bonded steel tapes is the most effective method for limiting vertical displacements and deformations, as well as increasing the load-bearing capacity of the tested angles by 28.6% compared to the reference elements. Considering the high cost of composite tapes, this is valuable information from an economic analysis perspective. The absence of steel tape delamination suggests that the bonding technique can be successfully employed in this reinforcement method and can replace welding, for example in facilities where there is a high fire hazard.
Thermo-Mechanical Numerical Simulation of Friction Stir Rotation-Assisted Single Point Incremental Forming of Commercially Pure Titanium Sheets
Authors: Szpunar Marcin , Trzepieciński Tomasz , Ostrowski Robert , Żaba Krzysztof , Ziaja Waldemar , Motyka Maciej
Published: June 2024

Single point incremental forming (SPIF) is becoming more and more widely used in the metal industry due to its high production flexibility and the possibility of obtaining larger material deformations than during conventional sheet metal forming processes. This paper presents the results of the numerical modeling of friction stir rotation-assisted SPIF of commercially pure 0.4 mm-thick titanium sheets. The aim of this research was to build a reliable finite element-based thermo-mechanical model of the warm forming process of titanium sheets. Finite element-based simulations were conducted in Abaqus/Explicit software (version 2019). The formability of sheet metal when forming conical cones with a slope angle of 45° was analyzed. The numerical model assumes complex thermal interactions between the forming tool, the sheet metal and the surroundings. The heat generation capability was used to heat generation caused by frictional sliding. Mesh sensitivity analysis showed that a 1 mm mesh provides the best agreement with the experimental results of total forming force (prediction error 3%). It was observed that the higher the size of finite elements (2 mm and 4 mm), the greater the fluctuation of the total forming force. The maximum temperature recorded in the contact zone using the FLIR T400 infrared camera was 157 °C, while the FE-based model predicted this value with an error of 1.3%. The thinning detected by measuring the drawpiece with the ARGUS non-contact strain measuring system and predicted by the FEM model showed a uniform thickness in the drawpiece wall zone. The FE-based model overestimated the minimum and maximum wall thicknesses by 3.7 and 5.9%, respectively.
A Robust Online Diagnostic Strategy of Inverter Open-Circuit Faults for Robotic Joint BLDC Motors
Authors: Metwly Mohamed Y. , Logan Victor M. , Clark Charles L. , He Jiangbiao , Xie Biyun
Published: June 2024

As robots are increasingly used in remote, safety-critical, and hazardous applications, the reliability of robots is becoming more important than ever before. Robotic arm joint motor-drive systems are vulnerable to hardware failures due to harsh operating environment in many scenarios, which may yield various joint failures and result in significant downtime costs. Targeting the most common robotic joint brushless DC (BLDC) motor-drive systems, this paper proposes a robust online diagnostic method for semiconductor faults for BLDC motor drives. The proposed fault diagnostic technique is based on the stator current signature analysis. Specifically, this paper investigates the performance of the BLDC joint motors under open-circuit faults of the inverter switches using finite element co-simulation tools. Furthermore, the proposed methodology is not only capable of detecting any open-circuit faults but also identifying faulty switches based on a knowledge table by considering various fault conditions. The robustness of the proposed technique was verified through extensive simulations under different speed and load conditions. Moreover, simulations have been carried out on a Kinova Gen-3 robot arm to verify the theoretical findings, highlighting the impacts of locked joints on the robot’s end-effector locations. Finally, experimental results are presented to corroborate the performance of the proposed fault diagnostic strategy.
Harnessing Brewery Spent Grain for Polyhydroxyalkanoate Production
Authors: Terfa Robe D. , Patel Priyanshi N. , Kim Hwidong D. , Gacura Matthew D. , Vanderlaan Gary , Chen Longyan , Ji Xiaoxu , Piovesan Davide
Published: June 2024

The utility of brewery spent grain (BSG), a byproduct of the beer production process, for the synthesis of polyhydroxyalkanoates (PHAs), is a significant advancement towards sustainable and cost-effective biopolymer production. This paper reviews the upcycling potential of BSG as a substrate for PHA production, utilizing various biotechnological approaches to convert this abundant waste material into high-value biodegradable polymers. Through a comprehensive review of recent studies, we highlight the biochemical composition of BSG and its suitability for microbial fermentation processes. This research delves into different methodologies for PHA production from BSG, including the use of mixed microbial cultures (MMCs) for the synthesis of volatile fatty acids (VFAs), a critical precursor in PHA production, and solid-state fermentation (SSF) techniques. We also examine the optimization of process parameters such as pH, temperature, and microbial concentration through the application of the Doehlert design, revealing the intricate relationships between these factors and their impact on VFA profiles and PHA yields. Additionally, this paper discusses challenges and future perspectives for enhancing the efficiency and economic viability of PHA production from BSG. By harnessing the untapped potential of BSG, this research contributes to the development of a circular economy model, emphasizing waste valorization and the creation of sustainable alternatives to conventional plastics.
Dynamical Analysis and Sliding Mode Controller for the New 4D Chaotic Supply Chain Model Based on the Product Received by the Customer
Authors: Johansyah Muhamad Deni , Vaidyanathan Sundarapandian , Sambas Aceng , Benkouider Khaled , Hamidzadeh Seyed Mohammad , Hidayanti Monika
Published: June 2024

Supply chains comprise various interconnected components like suppliers, manufacturers, distributors, retailers, and customers, each with unique variables and interactions. Managing dynamic supply chains is highly challenging, particularly when considering various sources of risk factors. This paper extensively explores dynamical analysis and multistability analysis to understand nonlinear behaviors and pinpoint potential risks within supply chains. Different phase portraits are used to demonstrate the impact of various factors such as transportation risk, quality risk, distortion, contingency reserves, and safety stock on both customers and retailers. We introduced a sliding mode control method that computes the sliding surface and its derivative by considering the error and its derivative. The equivalent control law based on the sliding surface and its derivative is derived and validated for control purposes. Our results show that the controller SMC can significantly enhance supply chain stability and efficiency. This research provides a robust framework for understanding complex supply chain dynamics and offers practical solutions to enhance supply chain resilience and flexibility.
Correction: Mergelyan, S.N.; Matevossian, H.A. Editorial: S. N. Mergelyan’s Dissertation “Best Approximations in the Complex Domain” (Short Version). Mathematics 2024, 12, 939
Authors: Mergelyan Sergey N. , Matevossian Hovik A.
Published: June 2024

The title should be corrected to “Editorial: S [...]
Blockchain-Enabled Secure Data Sharing with Honey Encryption and DSNN-Based Key Generation
Authors: Siyal Reshma , Long Jun , Asim Muhammad , Ahmad Naveed , Fathi Hanaa , Alshinwan Mohammad
Published: June 2024

Ensuring data confidentiality is a critical requirement for modern security systems globally. Despite the implementation of various access-control policies to enhance system security, significant threats persist due to insecure and inadequate access management. To address this, Multi-Party Authorization (MPA) systems employ multiple authorities for authorization and authentication, utilizing blockchain technology to store and access data securely, ensuring immutable and trusted audit trails. In this work, we propose a hybrid key-generation approach called the Identity and Attribute-Based Honey Encryption (IABHE) Algorithm combined with Deep Spiking Neural Network (DSNN) denoted by IABHE+DSNN for secure data sharing in a multi-party blockchain-based system. This approach incorporates various entities and multiple security functionalities to ensure data security. The data-sharing process involves several steps: initialization, authentication, initial registration, data protection, validation, and data sharing. Data protection is executed within the MapReduce framework, with data encryption performed using IABHE and key generation managed by DSNN. Experimental results demonstrate that the proposed IABHE+DSNN approach achieves a decryption time of 10.786 s, an encryption time of 15.765 s, and a key complexity of 0.887, outperforming existing methods.
PSF-C-Net: A Counterfactual Deep Learning Model for Person Re-Identification Based on Random Cropping Patch and Shuffling Filling
Authors: Sun Ruiwang , Chen Qing , Dong Heng , Zhang Haifeng , Wang Meng
Published: June 2024

In the task of person re-identification (re-ID), capturing the long-range dependency of instances is crucial for accurate identification. The existing methods excel at extracting local features but often overlook the global information of instance images. To address this limitation, we propose a convolution-based counterfactual learning framework, called PSF-C-Net, to focus on global information rather than local detailed features. PSF-C-Net adopts a parameter-sharing dual-path structure to perform counterfactual operations in the prediction space. It takes both the actual instance image and a counterfactual instance image that disrupts the contextual relationship as the input. The counterfactual framework enables the interpretable modeling of global features without introducing additional parameters. Additionally, we propose a novel method for generating counterfactual instance images, which effectively constructs an explicit counterfactual space, to reliably implement counterfactual strategies. We have conducted extensive experiments to evaluate the performance of PSF-C-Net on the Market-1501 and Duke-MTMC-reID datasets. The results demonstrate that PSF-C-Net achieves state-of-the-art performance.
Direct Aspiration Thrombectomy in the Management of Procedural Thromboembolic Complications Related to Endovascular Brain Aneurysm Treatment
Authors: Bogicevic Damljan , Vitosevic Filip , Milosevic Medenica Svetlana , Kalousek Vladimir , Vukicevic Marjana , Rasulic Lukas
Published: June 2024

Despite growing evidence over the last few years of the efficacy and safety of direct thrombus aspiration using a large bore distal access catheter as a type of mechanical thrombectomy procedure in acute stroke large-vessel occlusion patients, the experience and evidence of this technique for managing thromboembolic complications in endovascular aneurysm treatment is still limited and little research is available regarding this topic. We present a case of a thromboembolic occlusion of the left middle cerebral artery during the preprocedural angiograms of a large and fusiform left internal carotid artery aneurysm. This complication was successfully managed by navigating an already-placed distal access catheter intended for support during the opening of the flow-diverting stent; therefore, the thrombus was manually aspirated for two minutes, and Thrombolysis in Cerebral Infarction (TICI) scale 3 flow was restored. This case should encourage the use of a distal access catheter, already placed for aneurysm treatment, to perform zero-delay direct thrombus aspiration as a rescue approach for thromboembolic complications during endovascular treatments.
Radiation Techniques for Tracking the Progress of the Hydrometallurgical Leaching Process: A Case Study of Mn and Zn
Authors: Kiprono Nelson Rotich , Kawalec Anna , Klis Bartlomiej , Smolinski Tomasz , Rogowski Marcin , Kalbarczyk Paweł , Samczynski Zbigniew , Norenberg Maciej , Ostachowicz Beata , Adamowska Monika , Hyk Wojciech , Chmielewski Andrzej G.
Published: June 2024

With advancements in hardware and software, non-destructive radiometric analytical methods have become popular in a wide range of applications. A typical case is the study of the leaching process of metals from mineral ores and mine tailings. The objective of the current study was to develop a radiometric method based on neutron activation analysis (NAA), in particular, delayed gamma neutron activation analysis (DGNAA), to monitor the process of Mn and Zn leaching from Ti ore, Cu mine tailings, and Zn-Pb mine tailings. The DGNAA method was performed using a neutron source: a deuterium-tritium (D-T) neutron generator for Mn and a MARIA research nuclear reactor for Zn. Laboratory-scale Mn leaching from Ti ores, Cu tailings, and Zn-Pb tailings was investigated using delayed gamma-rays of 56Mn (half-life of 2.6 h). The dissolution efficiencies of Mn were found to increase with interaction time and HCl concentration (1 to 5 M) and to vary with the leaching temperature (22.5 to 110 °C). Such results were found to agree with those obtained by total reflection X-ray fluorescence (TXRF) spectrometry for the same samples. 65Zn (half-life of 244 days) was chosen to investigate real-time/online leaching of Zn in Ti ore, Cu tailings, and Zn-Pb tailings. During online monitoring, Zn recovery was also reported to increase with increased leaching time. After approximately 300 min of leaching, 80%, 79%, and 53% recovery of Zn in Zn-Pb tailings, Ti ore, and Cu tailings, respectively, were reported. Theoretically, developed mathematical prediction models for 65Zn radiotracer analysis showed that the spherical diffusion model requires much less time to attain saturation compared to the linear diffusion model. The results of NAA for Zn were compared with those obtained by handheld X-ray fluorescence (handheld-XRF) and TXRF analysis. The analyzed samples encompassed leached Ti ore, Cu tailings, and Zn-Pb tailings which were subjected to different conditions of leaching time, temperature, and HCl concentrations. The XRF analysis confirmed that the leaching efficiencies of Zn rise with the increase in leaching time and HCl concentration and fluctuate with leaching temperature. The developed approach is important and can be applied in laboratories and industrial setups for online monitoring of the recovery of any element whose isotopes can be activated using neutrons. The efficiency of the metal-recovery process has a direct impact on the normal operation and economic advantages of hydrometallurgy.
Interaction between α-Synuclein and Bioactive Lipids: Neurodegeneration, Disease Biomarkers and Emerging Therapies
Authors: Sanluca Chiara , Spagnolo Paolo , Mancinelli Romina , De Bartolo Maria Ilenia , Fava Marina , Maccarrone Mauro , Carotti Simone , Gaudio Eugenio , Leuti Alessandro , Vivacqua Giorgio
Published: June 2024

The present review provides a comprehensive examination of the intricate dynamics between α-synuclein, a protein crucially involved in the pathogenesis of several neurodegenerative diseases, including Parkinson’s disease and multiple system atrophy, and endogenously-produced bioactive lipids, which play a pivotal role in neuroinflammation and neurodegeneration. The interaction of α-synuclein with bioactive lipids is emerging as a critical factor in the development and progression of neurodegenerative and neuroinflammatory diseases, offering new insights into disease mechanisms and novel perspectives in the identification of potential biomarkers and therapeutic targets. We delve into the molecular pathways through which α-synuclein interacts with biological membranes and bioactive lipids, influencing the aggregation of α-synuclein and triggering neuroinflammatory responses, highlighting the potential of bioactive lipids as biomarkers for early disease detection and progression monitoring. Moreover, we explore innovative therapeutic strategies aimed at modulating the interaction between α-synuclein and bioactive lipids, including the development of small molecules and nutritional interventions. Finally, the review addresses the significance of the gut-to-brain axis in mediating the effects of bioactive lipids on α-synuclein pathology and discusses the role of altered gut lipid metabolism and microbiota composition in neuroinflammation and neurodegeneration. The present review aims to underscore the potential of targeting α-synuclein-lipid interactions as a multifaceted approach for the detection and treatment of neurodegenerative and neuroinflammatory diseases.
Comparative Mortality Analysis in Febrile and Afebrile Emergency Department Patients with Positive Blood Cultures: A Retrospective Study
Authors: Bonadia Nicola , Della Polla Davide Antonio , Murri Rita , D’Inzeo Tiziana , Fiori Barbara , Carnicelli Annamaria , Piccioni Andrea , Fuorlo Mariella , Petrucci Martina , Saviano Angela , Gasbarrini Antonio , Franceschi Francesco , Covino Marcello
Published: June 2024

This retrospective analysis at a major Italian university hospital (January 2018–September 2022) assessed the prognostic significance of fever in patients with bloodstream infections (BSIs). Of the 1299 patients with positive blood cultures, a comparison between febrile and afebrile patients at emergency department admission was conducted. This study particularly focused on the mortality rates associated with these two groups. Notably, afebrile patients exhibited a higher mortality rate. The odds ratio for mortality in afebrile patients was significantly higher compared to febrile patients. This suggests that the absence of fever might be an indicator of increased mortality risk, highlighting the complexity of diagnosing bloodstream infections based on fever presence. This study contributes to the understanding of fever as a diagnostic marker in emergency settings.
The Epistemology of Bacterial Virulence Factor Characterization
Authors: Jackson Matthew , Vineberg Susan , Theis Kevin R.
Published: June 2024

The field of microbial pathogenesis seeks to identify the agents and mechanisms responsible for disease causation. Since Robert Koch introduced postulates that were used to guide the characterization of microbial pathogens, technological advances have substantially increased the capacity to rapidly identify a causative infectious agent. Research efforts currently focus on causation at the molecular level with a search for virulence factors (VFs) that contribute to different stages of the infectious process. We note that the quest to identify and characterize VFs sometimes lacks scientific rigor, and this suggests a need to examine the epistemology of VF characterization. We took this premise as an opportunity to explore the epistemology of VF characterization. In this perspective, we discuss how the characterization of various gene products that evolved to facilitate bacterial survival in the broader environment have potentially been prematurely mischaracterized as VFs that contribute to pathogenesis in the context of human biology. Examples of the reasoning that can affect misinterpretation, or at least a premature assignment of mechanistic causation, are provided. Our aim is to refine the categorization of VFs by emphasizing a broader biological view of their origin.
New Strategies in Archaeometric Provenance Analyses of Volcanic Rock Grinding Stones: Examples from Iulia Libica (Spain) and Sidi Zahruni (Tunisia)
Authors: Casas Lluís , Di Febo Roberta , Anglisano Anna , Pitarch Martí África , Queralt Ignasi , Carreras Cèsar , Fouzai Boutheina
Published: June 2024

Archaeometry can help archaeologists in many ways, and one of the most common archaeometric objectives is provenance analysis. Volcanic rocks are often found in archaeological sites as materials used to make grinding tools such as millstones and mortars or as building materials. Petrographic characterization is commonly applied to identify their main mineralogical components. However, the provenance study of volcanic stones is usually undertaken by comparing geochemical data from reference outcrops using common descriptive statistical tools such as biplots of chemical elements, and occasionally, unsupervised multivariate data analysis like principal component analysis (PCA) is also used. Recently, the use of supervised classification methods has shown a superior performance in assigning provenance to archaeological samples. However, these methods require the use of reference databases for all the possible provenance classes in order to train the classification models. The existence of comprehensive collections of published geochemical analyses of igneous rocks enables the use of the supervised approach for the provenance determination of volcanic stones. In this paper, the provenance of volcanic grinding tools from two archaeological sites (Iulia Libica, Spain, and Sidi Zahruni, Tunisia) is attempted using data from the GEOROC database through unsupervised and supervised approaches. The materials from Sidi Zahruni have been identified as basalts from Pantelleria (Italy), and the agreement between the different supervised classification models tested is particularly conclusive. In contrast, the provenance of the materials from Iulia Libica remained undetermined. The results illustrate the advantages and limitations of all the examined methods.
Adsorption of the Herbicide Endosulfan by Newly Discovered Zeolitic Tuffs in Mexico
Authors: Santamaria-Juarez Juana Deisy , Hernández Miguel Ángel , Hernández Gabriela Itzel , Álvarez Karin Monserrat , Rubio Efraín , Portillo Roberto , Velasco María de los Ángeles , Aquino Josue Fernando , Petranovskii Vitalii
Published: June 2024

The study presents experimental results on the adsorption of endosulfan in new natural zeolite deposits from Mexico. The adsorption of this herbicide was evaluated using inverse gas chromatography with a thermal conductivity detector and helium as the carrier gas. The experimental adsorption data were analyzed using the Langmuir and Freundlich equations in their linear form over a temperature range of 413–573 K. The study also estimated thermodynamic parameters such as the Free Energy of Gibbs (ΔG), isosteric enthalpy of adsorption (ΔH), and entropy change (ΔS) within this temperature range. The results indicated that the zeolites studied had a low adsorption capacity for this herbicide under the experimental conditions. The study also quantitatively determined the presence of starting minerals, with Na-Mordenite and Na-Clinoptilolite being the most prevalent, followed by Ca-Chabazite, Ca-Clinoptilolite, and Montmorillonite, with Quartz being present in low amounts. The NMOR zeolite underwent ion exchanges with AgNO3 to produce the Ag-MOR zeolite and assess its herbicide adsorption capacity. Another mineral, Ca-Stilbite, was present in higher quantities than Ca-Clinoptilolite and Quartz.
Electronic-Structure-Modulated Cu,Co-Coanchored N-Doped Nanocarbon as a Difunctional Electrocatalyst for Hydrogen Evolution and Oxygen Reduction Reactions
Authors: Cao Liyun , Liu Rui , Huang Yixuan , Chu Dewei , Li Mengyao , Xu Guoting , Li Xiaoyi , Huang Jianfeng , Zhao Yong , Feng Liangliang
Published: June 2024

To alleviate the problems of environmental pollution and energy crisis, aggressive development of clean and alternative energy technologies, in particular, water splitting, metal–air batteries, and fuel cells involving two key half reactions comprising hydrogen evolution reaction (HER) and oxygen reduction (ORR), is crucial. In this work, an innovative hybrid comprising heterogeneous Cu/Co bimetallic nanoparticles homogeneously dispersed on a nitrogen-doped carbon layer (Cu/Co/NC) was constructed as a bifunctional electrocatalyst toward HER and ORR via a hydrothermal reaction along with post-solid-phase sintering technique. Thanks to the interfacial coupling and electronic synergism between the Cu and Co bimetallic nanoparticles, the Cu/Co/NC catalyst showed improved catalytic ORR activity with a half-wave potential of 0.865 V and an excellent stability of more than 30 h, even compared to 20 wt% Pt/C. The Cu/Co/NC catalyst also exhibited excellent HER catalytic performance with an overpotential of below 149 mV at 10 mA/cm2 and long-term operation for over 30 h.
In Situ Preparation of Chlorine-Regenerable Antimicrobial Polymer Molecular Sieve Membranes
Authors: Zhang Yu , Qian Yiduo , Wen Yuheng , Gui Qiudi , Xu Yixin , Lu Xiuhong , Zhang Li , Song Wenliang
Published: June 2024

Microbial contamination has profoundly impacted human health, and the effective eradication of widespread microbial issues is essential for addressing serious hygiene concerns. Taking polystyrene (PS) membrane as an example, we herein developed report a robust strategy for the in situ preparation of chlorine-regenerable antimicrobial polymer molecular sieve membranes through combining post-crosslinking and nucleophilic substitution reaction. The cross-linking PS membranes underwent a reaction with 5,5-dimethylhydantoin (DMH), leading to the formation of polymeric N-halamine precursors (PS-DMH). These hydantoinyl groups within PS-DMH were then efficiently converted into biocidal N-halamine structures (PS-DMH-Cl) via a simple chlorination process. ATR-FTIR and XPS spectra were recorded to confirm the chemical composition of the as-prepared PS-DMH-Cl membranes. SEM analyses revealed that the chlorinated PS-DMH-Cl membranes displayed a rough surface with a multitude of humps. The effect of chlorination temperature and time on the oxidative chlorine content in the PS-DMH-Cl membranes was systematically studied. The antimicrobial assays demonstrated that the PS-DMH-Cl membranes could achieve a 6-log inactivation of E. coli and S. aureus within just 4 min of contact time. Additionally, the resulting PS-DMH-Cl membranes exhibited excellent stability and regenerability of the oxidative chlorine content.
Lavandula angustifolia Essential Oil Inhibits the Ability of Fusobacterium nucleatum to Produce Volatile Sulfide Compounds, a Key Components in Oral Malodor
Authors: Rosner Ofir , Livne Shiri , Bsharat Maria , Dviker Shir , Jeffet Uziel , Matalon Shlomo , Sterer Nir
Published: June 2024

Oral malodor still constitutes a major challenge worldwide. A strong effort is invested in eliminating volatile sulfur compound-producing oral bacteria through organic natural products such as essential oils. Fusobacterium nucleatum is a known volatile sulfur compound-producing bacteria that inspires oral malodor. The aim of the present study was to test the effect of lavender essential oil on the bacterium’s ability to produce volatile sulfide compounds, the principal components of oral malodor. Lavender (Lavandula angustifolia) essential oil was extracted by hydrodistillation and analyzed using GC-MS. The minimal inhibitory concentration (MIC) of lavender essential oil on Fusobacterium nucleatum was determined in a previous trial. Fusobacterium nucleatum was incubated anaerobically in the presence of sub-MIC, MIC, and above MIC concentrations of lavender essential oil, as well as saline and chlorhexidine as negative and positive controls, respectively. Following incubation, volatile sulfur compound levels were measured using GC (Oralchroma), and bacterial cell membrane damage was studied using fluorescence microscopy. Chemical analysis of lavender essential oil yielded five main components, with camphor being the most abundant, accounting for nearly one-third of the total lavender essential oil volume. The MIC (4 µL/mL) of lavender essential oil reduced volatile sulfur compound secretion at a statistically significant level compared to the control (saline). Furthermore, the level of volatile sulfur compound production attributed to 1 MIC of lavender essential oil was in the range of the positive control chlorhexidine with no significant difference. When examining bacterial membrane damage, 2 MIC of lavender essential oil (i.e., 8 µL/mL) demonstrated the same, showing antibacterial membrane damage values comparative to chlorhexidine. Since lavender essential oil was found to be highly effective in hindering volatile sulfur compound production by Fusobacterium nucleatum through the induction of bacterial cell membrane damage, the results suggest that lavender essential oil may be a suitable alternative to conventional chemical-based anti-malodor agents.
Insights into Actin Isoform-Specific Interactions with Myosin via Computational Analysis
Authors: Yu Chan Jong , Park Yoon Ho , An Mi Young , Ryu Bumhan , Jung Hyun Suk
Published: June 2024

Actin, which plays a crucial role in cellular structure and function, interacts with various binding proteins, notably myosin. In mammals, actin is composed of six isoforms that exhibit high levels of sequence conservation and structural similarity overall. As a result, the selection of actin isoforms was considered unimportant in structural studies of their binding with myosin. However, recent high-resolution structural research discovered subtle structural differences in the N-terminus of actin isoforms, suggesting the possibility that each actin isoform may engage in specific interactions with myosin isoforms. In this study, we aimed to explore this possibility, particularly by understanding the influence of different actin isoforms on the interaction with myosin 7A. First, we compared the reported actomyosin structures utilizing the same type of actin isoforms as the high-resolution filamentous skeletal α-actin (3.5 Å) structure elucidated using cryo-EM. Through this comparison, we confirmed that the diversity of myosin isoforms leads to differences in interaction with the actin N-terminus, and that loop 2 of the myosin actin-binding sites directly interacts with the actin N-terminus. Subsequently, with the aid of multiple sequence alignment, we observed significant variations in the length of loop 2 across different myosin isoforms. We predicted that these length differences in loop 2 would likely result in structural variations that would affect the interaction with the actin N-terminus. For myosin 7A, loop 2 was found to be very short, and protein complex predictions using skeletal α-actin confirmed an interaction between loop 2 and the actin N-terminus. The prediction indicated that the positively charged residues present in loop 2 electrostatically interact with the acidic patch residues D24 and D25 of actin subdomain 1, whereas interaction with the actin N-terminus beyond this was not observed. Additionally, analyses of the actomyosin-7A prediction models generated using various actin isoforms consistently yielded the same results regardless of the type of actin isoform employed. The results of this study suggest that the subtle structural differences in the N-terminus of actin isoforms are unlikely to influence the binding structure with short loop 2 myosin 7A. Our findings are expected to provide a deeper understanding for future high-resolution structural binding studies of actin and myosin.
Data-Driven and Machine Learning to Screen Metal–Organic Frameworks for the Efficient Separation of Methane
Authors: Guan Yafang , Huang Xiaoshan , Xu Fangyi , Wang Wenfei , Li Huilin , Gong Lingtao , Zhao Yue , Guo Shuya , Liang Hong , Qiao Zhiwei
Published: June 2024

With the rapid growth of the economy, people are increasingly reliant on energy sources. However, in recent years, the energy crisis has gradually intensified. As a clean energy source, methane has garnered widespread attention for its development and utilization. This study employed both large-scale computational screening and machine learning to investigate the adsorption and diffusion properties of thousands of metal–organic frameworks (MOFs) in six gas binary mixtures of CH4 (H2/CH4, N2/CH4, O2/CH4, CO2/CH4, H2S/CH4, He/CH4) for methane purification. Firstly, a univariate analysis was conducted to discuss the relationships between the performance indicators of adsorbents and their characteristic descriptors. Subsequently, four machine learning methods were utilized to predict the diffusivity/selectivity of gas, with the light gradient boosting machine (LGBM) algorithm emerging as the optimal one, yielding R2 values of 0.954 for the diffusivity and 0.931 for the selectivity. Furthermore, the LGBM algorithm was combined with the SHapley Additive exPlanation (SHAP) technique to quantitatively analyze the relative importance of each MOF descriptor, revealing that the pore limiting diameter (PLD) was the most critical structural descriptor affecting molecular diffusivity. Finally, for each system of CH4 mixture, three high-performance MOFs were identified, and the commonalities among high-performance MOFs were analyzed, leading to the proposals of three design principles involving changes only to the metal centers, organic linkers, or topological structures. Thus, this work reveals microscopic insights into the separation mechanisms of CH4 from different binary mixtures in MOFs.
Echinacea Supplementation Does Not Impact Aerobic Capacity and Erythropoiesis in Athletes: A Meta-Analysis
Authors: Deccy Stephanie , Bartkowiak Callie , Rodricks Nathan , Paultre Kristopher
Published: June 2024

Athletes are increasingly relying on natural supplements to improve athletic performance. Echinacea, a common herbal supplement, has been studied for its potential erythropoietin-enhancing effects, with mixed results in the literature. The purpose of this meta-analysis is to determine whether echinacea supplementation has erythropoietic or ergogenic effects in athletes. A search strategy was developed to identify trials studying the impact of echinacea supplementation on erythropoiesis and maximal oxygen uptake. The database search yielded 502 studies, 496 of which were excluded in the two-reviewer screening process. Six studies with a total of 107 athletes were included in the analysis. For hemoglobin and hematocrit levels, there were small, positive effect sizes when comparing the difference in pre- and post-intervention levels between the echinacea and placebo groups, at 0.38 (p = 0.02, 95% CI −0.04–0.80, I2 = 70%) and 0.34 (p < 0.01, 95% CI −0.10–0.78, I2 = 86%), respectively, though they did not reach statistical significance. There was also no statistically significant change in erythropoietin (effect size −0.29, p = 0.05, 95% CI −0.75–0.17, I2 = 67%) or maximal oxygen uptake (effect size −0.20, p = 0.95, 95% CI −0.60–0.21, I2 = 0%). Echinacea supplementation did not influence erythropoietin, hemoglobin, hematocrit, or maximal oxygen uptake in athletes; however, the evidence base is limited.
Using the Theory of Perceived Value to Determine the Willingness to Consume Foods from a Healthy Brand: The Role of Health Consciousness
Authors: Albornoz Roger , García-Salirrosas Elizabeth Emperatriz , Millones-Liza Dany Yudet , Villar-Guevara Miluska , Toyohama-Pocco Gladys
Published: June 2024

Eating low amounts of healthy foods leads to high rates of diet-related diseases. How can we control and reduce the increase in these diseases? One of the recommendations is to improve nutritional competence, which means greater health consciousness. The objective of the present study is to determine the influence of health consciousness on the dimensions of perceived value and their impact on the willingness to consume foods from a healthy brand. Through a non-experimental, cross-sectional, and explanatory study, the responses of 518 participants (men and women) who confirmed being consumers of the healthy brands of food were analyzed. The study included adults aged from 18 to 58 years recruited using non-probability sampling. Data was collected using a self-report form and statistically analyzed using Smart PLS. The findings support that health awareness positively and significantly influences perceived quality value, perceived financial value, perceived social value, and perceived emotional value; contrary to this, it was detected that the perceived financial value does not influence the willingness to consume foods from healthy brands. This study contributes significantly to health science by showing how the theory of perceived value predicts the intention to consume healthy brands, with health consciousness intervening in this prediction. Therefore, it is concluded that the study population that consumes healthy foods has experienced the positive impact of perceived value and reports that the factors that comprise it influence their intention to consume healthy foods.
Integrative Approach of Treating Early Undernutrition with an Enriched Black Corn Chip, Study on a Murine Model
Authors: Urquiza-Martínez Mercedes-Victoria , Fabián-Avilés Imelda M. , Torner Luz , Servín-Campuzano Hermelinda , González-Avilés Mauricio
Published: June 2024

Undernutrition (UN) increases child vulnerability to illness and mortality. Caused by a low amount and/or poor quality of food intake, it impacts physical, cognitive, and social development. Modern types of food consumption have given highly processed food a higher cultural value compared to minimally processed food. Objective: The objective of this study was to evaluate the effect on growth, metabolism, physical activity (PA), memory, inflammation, and toxicity of an enriched black corn chip (BC) made with endemic ingredients on post-weaned UN mice. Methods: A chip was made with a mixture of black corn, fava beans, amaranth, and nopal cactus. To probe the effects of UN, UN was induced in 3wo post-weaned male C57Bl/6j mice through a low-protein diet (LPD—50% of the regular requirement of protein) for 3w. Then, the BC was introduced to the animals’ diet (17%) for 5w; murinometric parameters were measured, as were postprandial glucose response, PA, and short-term memory. Histological analysis was conducted on the liver and kidneys to measure toxicity. Gene expression related to energy balance, thermogenesis, and inflammation was measured in adipose and hypothalamic tissues. Results: Treatment with the BC significantly improved mouse growth, even with a low protein intake, as evidenced by a significant increase in body weight, tail length, cerebral growth, memory improvement, physical activation, normalized energy expenditure (thermogenesis), and orexigenic peptides (AGRP and NPY). It decreased anorexigenic peptides (POMC), and there was no tissue toxicity. Conclusions: BC treatment, even with persistent low protein intake, is a promising strategy against UN, as it showed efficacy in correcting growth deficiency, cognitive impairment, and metabolic problems linked to treatment by adjusting energy expenditure, which led to the promotion of energy intake and regulation of thermogenesis, all by using low-cost, accessible, and endemic ingredients.
Improved Equations of the Lagrange Top and Examples of Analytical Solutions
Authors: Deriglazov Alexei A.
Published: June 2024

Equations of a heavy rotating body with one fixed point can be deduced starting from a variational problem with holonomic constraints. When applying this formalism to the particular case of a Lagrange top, in the formulation with a diagonal inertia tensor the potential energy has a more complicated form as compared with that assumed in the literature on dynamics of a rigid body. This implies the corresponding improvements in equations of motion. Therefore, we revised this case, presenting several examples of analytical solutions to the improved equations. The case of precession without nutation has a surprisingly rich relationship between the rotation and precession rates, which is discussed in detail.
Molecular Characterization and Antibacterial Resistance Determination of Escherichia coli Isolated from Fresh Raw Mussels and Ready-to-Eat Stuffed Mussels: A Major Public Health Concern
Authors: Yibar Artun , Saticioglu Izzet B. , Ajmi Nihed , Duman Muhammed
Published: June 2024

Our study focused exclusively on analyzing Escherichia coli (E. coli) contamination in fresh raw mussels and ready-to-eat (RTE) stuffed mussels obtained from authorized and regulated facilities. However, it is critical to recognize that such contamination represents a significant public health threat in regions where unauthorized harvesting and sales practices are prevalent. This study aimed to comprehensively assess the prevalence, molecular characteristics, and antibacterial resistance profiles of E. coli in fresh raw mussels and RTE stuffed mussels. E. coli counts in fresh raw mussel samples ranged from 1 to 2.89 log CFU/g before cooking, with a significant reduction observed post-cooking. RTE stuffed mussel samples predominantly exhibited negligible E. coli presence (<1 log CFU/g). A phylogenetic analysis revealed a dominance of phylogroup A, with variations in the distribution observed across different sampling months. Antibacterial resistance was prevalent among the E. coli isolates, notably showing resistance to ampicillin, streptomycin, and cefotaxime. Extended-spectrum β-lactamase (ESβL) production was rare, with only one positive isolate detected. A variety of antibacterial resistance genes, including tetB and sul1, were identified among the isolates. Notably, virulence factor genes associated with pathogenicity were absent. In light of these findings, it is imperative to maintain rigorous compliance with quality and safety standards at all stages of the mussel production process, encompassing harvesting, processing, cooking, and consumption. Continuous monitoring, implementation of rigorous hygiene protocols, and responsible antibacterial drug use are crucial measures in mitigating food safety risks and combating antibacterial resistance. Stakeholders, including seafood industry players, regulatory agencies, and healthcare professionals, are essential to ensure effective risk mitigation and safeguard public health in the context of seafood consumption.