bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors Associated with Trust in Public Authorities Among Adults in Norway, United Kingdom, United States, and Australia Two Years after the COVID-19 Outbreak
Authors: Price Daicia , Bonsaksen Tore , Leung Janni , McClure-Thomas Caitlin , Ruffolo Mary , Lamph Gary , Kabelenga Isaac , Ostertun Geirdal Amy
Published: August 2023

Objectives: This study aimed to examine the levels of trust in information provided by public authorities 2 years after the COVID-19 outbreak and to examine factors associated with trust.

Methods: Using a cross-national approach, online survey data was collected from four Western countries—Australia, Norway, the United Kingdom, and the United States of America. Differences in reports of very low or low levels of trust were examined by age, gender, area of residence, and the highest level of education in the four countries.

Results: Levels of trust in the public authorities’ information were highest among Norwegian respondents and lowest among U.K. respondents. Lower levels of trust in public authorities were found among males, individuals living in rural or remote areas, and those with lower levels of education.

Conclusion: The outcomes contribute to knowledge regarding differences between socio-demographic groups and countries regarding the levels of trust people have in public authorities’ information concerning a crisis, such as COVID-19. Strategies to promote trust in societies in different countries could consider these socio-demographic differences.
Influence of the microbiota on the effectiveness and toxicity of oncological therapies, with a focus on chemotherapy
Authors: Cazzaniga Massimiliano , Zonzini Giordano Bruno , Di Pierro Francesco , Palazzi Chiara Maria , Cardinali Marco , Bertuccioli Alexander
Published: August 2023

Recent studies have highlighted a possible correlation between microbiota composition and the pathogenesis of various oncological diseases. Also, many bacterial groups are now directly or indirectly associated with the capability of stimulating or inhibiting carcinogenic pathways. However, little is known about the importance and impact of microbiota patterns related to the efficacy and toxicity of cancer treatments. We have recently begun to understand how oncological therapies and the microbiota are closely interconnected and could influence each other. Chemotherapy effectiveness, for example, appears to be strongly influenced by the presence of some microorganisms capable of modulating the pharmacokinetics and pharmacodynamics of the compounds used, thus varying the real response and therefore the efficacy of the oncological treatment. Similarly, chemotherapeutic agents can modulate the microbiota with variations that could facilitate or avoid the onset of important side effects. This finding has or could have considerable relevance as it is possible that our ability to modulate and modify the microbial structure before, during, and after treatment could influence all the clinical parameters related to pharmacological treatments and, eventually, the prognosis of the disease.
Assessing Spatial Variation and Driving Factors of Available Phosphorus in a Hilly Area (Gaozhou, South China) Using Modeling Approaches and Digital Soil Mapping
Authors: Zhang Wenhui , Cheng Liangwei , Xu Ruitao , He Xiaohua , Mo Weihan , Xu Jianbo
Published: August 2023

Soil fertility plays a crucial role in crop growth, so it is important to study the spatial distribution and variation of soil fertility for agricultural management and decision-making. However, traditional methods for assessing soil fertility are time-consuming and economically burdensome. Moreover, it is hard to capture the spatial variation of soil properties across continuous geographic space using the conventional methods. As key techniques of digital soil mapping (DSM), spatial interpolation techniques have been widely applied in soil surveys and analysis in recent years, since they can predict soil properties at unknown points in continuous space based on limited sample points. However, further research is needed on spatial interpolation models for DSM in regions with variable climates and complex terrains, which are characterized by strong spatial variation in both environmental variables and soil fertility. In this study, taking a typical hilly area in a subtropical monsoon climate, i.e., Gaozhou, Guangdong Province, China, as an example, the performances of four popular spatial interpolation models (Random Forest (RF), Ordinary Kriging, Inverse Distance Weighting, and Radial Basis Function) for digital soil mapping on available phosphorus (AP) are compared. Based on RF, the spatial variation and its driving factors of the AP of Gaozhou are then analyzed. Furthermore, by selecting three typical truncation lines from different directions, the correlations between environmental variables and AP in different spatial positions are demonstrated. The root mean square error (RMSE) results of the above four models are 32.01, 32.08, 32.74, and 33.08, respectively, which indicate that the RF has a higher interpolation accuracy. Based on the mapping results of RF, the minimum, maximum, and mean values of AP in the study area are 38.90, 95.24, and 64.96 mg/kg, respectively. The high-value areas of AP are mainly distributed in forested and orchard areas, while the low-value areas are primarily found in urban and cultivated areas in the eastern and western regions. Vegetation and topography are identified as the key factors shaping the spatial variations of AP in the study area. Furthermore, the spatial heterogeneity of the influence strength of altitude and EVI is revealed, providing a new direction for further research on DSM in the future, i.e., spatial interpolation models considering the spatial heterogeneity of the influence of environmental variables.
Seed Germination and Plant Growth under Drought Stress of Herbicide-Resistant and Herbicide-Susceptible Biotypes of Conyza Species and Smart Farming Approaches
Authors: Kanatas Panagiotis , Ntaoulis Vasilis , Gazoulis Ioannis , Andreou Athanasios , Danaskos Marios , Mpounanos Dimitrios , Karanika Eleni-Anna , Papastylianou Panayiota , Travlos Ilias
Published: August 2023

Horseweed (C. canadensis) and fleabane (C. sumatrensis) are two annual or perennial herbaceous weeds present with high frequency and density in many parts of the world. Their response to water deficit was studied by means of seed germination tests and pot experiments. Seed germination was tested in solutions with different concentrations of polyethylene glycol (PEG). Two biotypes of each species were examined, one glyphosate resistant and the other susceptible. Growth responses were similar in the two species, both being more affected by lower (−1 MPa) than higher water potential (−0.2 MPa). The results revealed a significant effect of the biotype and the weed species on the drought stress response and adaptation. When high PEG concentrations were applied (−0.6 MPa), both C. sumatrensis biotypes had higher germination percentages (up to 88%) than the C. canadensis biotypes, while in most cases the seeds of the resistant biotypes germinated more (up to 72%) compared to the susceptible ones. These findings were confirmed by means of NDVI values, indicating that remote sensing can be used for a quick evaluation of the drought stress response of these weeds. The results obtained highlight the significant effect of species, biotypes and drought stress level on the germination, survival and growth of the weeds.
Production of Zirconium-Niobium Alloys for Nuclear Reactors Fuel Rods via SHS Process
Authors: Mukhachev Anatoly , Yelatontsev Dmytro , Kharytonova Olena
Published: August 2023

This article presents the results of studies of the self-propagating high-temperature synthesis (SHS) for obtaining zirconium alloys with niobium by the method of calcium-thermal reduction of nuclear-grade zirconium tetrafluoride in the presence of niobium powder. The optimal heating temperature of the initial charge and the methods of charge mixture with different calcium content were determined. The safety of the SHS process is ensured by the formation of an optimal combustion front of the mixture to remove the released high-pressure gases. A setup for the furnace reduction of zirconium alloys with charge preheating, discharge of molten products into molds of various designs, and control of the time and rate of slag and alloy crystallization has been tested. The required performance of the installation, the degree of transition of zirconium from salt into the alloy, and the purity, structure, and uniformity of the alloy were achieved.
Prediction of Stroke Disease with Demographic and Behavioural Data Using Random Forest Algorithm
Authors: Shobayo Olamilekan , Zachariah Oluwafemi , Odusami Modupe Olufunke , Ogunleye Bayode
Published: August 2023

Stroke is a major cause of death worldwide, resulting from a blockage in the flow of blood to different parts of the brain. Many studies have proposed a stroke disease prediction model using medical features applied to deep learning (DL) algorithms to reduce its occurrence. However, these studies pay less attention to the predictors (both demographic and behavioural). Our study considers interpretability, robustness, and generalisation as key themes for deploying algorithms in the medical domain. Based on this background, we propose the use of random forest for stroke incidence prediction. Results from our experiment showed that random forest (RF) outperformed decision tree (DT) and logistic regression (LR) with a macro F1 score of 94%. Our findings indicated age and body mass index (BMI) as the most significant predictors of stroke disease incidence.
Cumulative and Rolling Horizon Prediction of Overall Equipment Effectiveness (OEE) with Machine Learning
Authors: Dobra Péter , Jósvai János
Published: August 2023

Nowadays, one of the important and indispensable conditions for the effectiveness and competitiveness of industrial companies is the high efficiency of manufacturing and assembly. These enterprises based on different methods and tools systematically monitor their efficiency metrics with Key Performance Indicators (KPIs). One of these most frequently used metrics is Overall Equipment Effectiveness (OEE), the product of availability, performance and quality. In addition to monitoring, it is also necessary to predict efficiency, which can be implemented with the support of machine learning techniques. This paper presents and compares several supervised machine learning techniques amongst other polynomial regression, lasso regression, ridge regression and gradient boost regression. The aim of this article is to determine the best estimation method for semiautomatic assembly line and large batch size. The case study presented with a real industrial example gives the answer as to which of the cumulative or rolling horizon prediction methods is more accurate.
Heterogeneous Copper Catalysts in the Aqueous Phase Hydrogenation of Maltose to Sorbitol
Authors: Pappalardo Valeria , Zaccheria Federica , Scotti Nicola , Ravasio Nicoletta
Published: August 2023

A one-pot hydrogenolysis/hydrogenation reaction of maltose to two moles of sorbitol has been carried out over different supported Cu catalysts in water at 180 °C and 40 bar of H2. Only the catalysts supported on silicas were found to be effective in this reaction, giving up to 86% yield in the desired product while the bare supports and the catalysts supported on alumina or silica alumina gave messy reactions. The peculiar activity of the two Cu/Silica systems tested was ascribed to high metal dispersion and suitable polarity of the catalyst surface. In exposing metallic Cu particles on the surface, the reduced catalyst showed unusual stability in the presence of water as a solvent and could be reused several times without any treatment.
Water-Glass-Assisted Foaming in Foamed Glass Production
Authors: Smiljanić Sonja , Hribar Uroš , Spreitzer Matjaž , König Jakob
Published: August 2023

The energy efficiency of buildings can be greatly improved by decreasing the energy embodied in installed materials. In this contribution, we investigated the possibility of foaming waste bottle glass in the air atmosphere with the addition of water glass, which would reduce the energy used in the production of foamed glass boards. The results show that with the increased addition of water glass, the crystallinity and the thermal conductivity decrease, however, the remaining crystal content prevents the formation of closed-porous foams. The added water glass only partly protects the carbon from premature oxidation, and the foaming mechanism in the air is different than in the argon atmosphere. The lowest obtained foam density in the air atmosphere is 123 kg m−3, while the lowest thermal conductivity is 53 mW m−1 K−1, with an open porosity of 50% for the sample obtained in the air, containing 12 wt% of water glass, 2 wt% of B2O3, 2 wt% AlPO4 and 2 wt% K3PO4.
Multi-UAV Cooperative Obstacle Avoidance of 3D Vector Field Histogram Plus and Dynamic Window Approach
Authors: Wang Xinhua , Cheng Mingyan , Zhang Shuai , Gong Huajun
Published: August 2023

In this paper, we propose a fusion algorithm that integrates the 3D vector field histogram plus (VFH+) algorithm and the improved dynamic window approach (DWA) algorithm. The aim is to address the challenge of cooperative obstacle avoidance faced by multi-UAV formation flying in unknown environments. First, according to the navigation evaluation function of the standard DWA algorithm, the target distance is introduced to correct the azimuth. Then, aiming at the problem that the fixed weight mechanism in standard DWA algorithm is unreasonable, we combine the A* algorithm and introduce variable weight factors related to azimuth to improve the target orientation ability in local path planning. A new rotation cost evaluation function is added to improve the obstacle avoidance ability of two-dimensional UAV. Then, 3D VFH+ algorithm is introduced and integrated with improved DWA algorithm to design a distributed cooperative formation obstacle avoidance control algorithm. Simulation validation suggests that compared with the traditional DWA algorithm, the improved collaborative obstacle avoidance control algorithm can greatly optimize the obstacle avoidance effect of UAVs’ formation flight.
Deep Learning Models Outperform Generalized Machine Learning Models in Predicting Winter Wheat Yield Based on Multispectral Data from Drones
Authors: Li Zongpeng , Chen Zhen , Cheng Qian , Fei Shuaipeng , Zhou Xinguo
Published: August 2023

Timely and accurate monitoring of winter wheat yields is beneficial for the macro-guidance of agricultural production and for making precise management decisions throughout the winter wheat reproductive period. The accuracy of crop yield prediction can be improved by combining unmanned aerial vehicle (UAV)-based multispectral data with deep learning algorithms. In this study, 16 yield-sensitive vegetation indices were constructed, and their correlations were analyzed based on UAV multispectral data of winter wheat at the heading, flowering, and filling stages. Seven input variable sets were obtained based on the combination of data from these three periods, and four generalized machine learning algorithms (Random Forest (RF), K-Nearest Neighbor (KNN), Bagging, and Gradient Boosting Regression (GBR)) and one deep learning algorithm (1D Convolutional Neural Network (1D-CNN)) were used to predict winter wheat yield. The results showed that the RF model had the best prediction performance among the generalised machine learning models. The CNN model achieved the best prediction accuracy based on all seven sets of input variables. Generalised machine learning models tended to underestimate or overestimate yields under different irrigation treatments, with good prediction performance for observed yields < 7.745 t·ha−1. The CNN model showed the best prediction performance based on most input variable groups across the range of observed yields. Most of the differences between observed and predicted values (Yi) for the CNN models were distributed between −0.1 t·ha−1 and 0.1 t·ha−1, and the model was relatively stable. Therefore, the CNN model is recommended in this study for yield prediction and as a reference for future precision agriculture research.
Robust Multiple Unmanned Aerial Vehicle Network Design in a Dense Obstacle Environment
Authors: Zhang Chen , Yao Wen , Zuo Yuan , Wang Hongliang , Zhang Chuanfu
Published: August 2023

Highly robust networks can resist attacks, as when some UAVs fail, the remaining UAVs can still transmit data to each other. In order to improve the robustness of a multi-UAV network, most methods construct the network by adjusting the positions of the UAVs and adding a large number of links. However, having a large number of links greatly consumes communication resources and increases serious signal interference. Therefore, it is necessary to study a method that can improve robustness and reduce the number of links. In this paper, we propose a method that consists of combining formation control and link selection, which can work in a distributed manner. For formation control, our method keeps the UAVs compact in the obstacle environment through an improved artificial potential field. The compact formation enables UAVs to have a large number of neighbors. For link selection, reinforcement learning is used to improve the robustness of the network and reduce the number of network edges. In the simulation of the 3D urban environment, three failure modes are used to verify the robustness of the network. The experimental results show that even if the number of links is reduced by 20%, the networks designed by our method still have strong robustness.
Sustainable Energy Data Centres: A Holistic Conceptual Framework for Design and Operations
Authors: Murino Teresa , Monaco Roberto , Nielsen Per Sieverts , Liu Xiufeng , Esposito Gianluigi , Scognamiglio Carlo
Published: August 2023

Data Centres serve as the foundation for digital technologies in the energy sector, enabling advanced analytics, optimization, and automation. However, their rapid growth can exert a substantial influence on the environment due to their energy consumption, water utilization, and production of electronic waste. This research begins with an energy overview of the setup and operations of data centres, highlighting their key components and infrastructure, and emphasizing their crucial role in managing energy resources and driving the energy sector’s digital technologies. Building upon this understanding, a holistic framework is proposed to tackle energy sustainability concerns in data centres, with a focus on energy-related aspects. The framework places emphasis on three primary sustainability metrics, namely energy efficiency, water consumption, and waste management. It underscores the significance of green building design principles and energy-efficient equipment as crucial constituents of sustainable data centre infrastructure. The framework delineates optimal energy operational best practices encompassing virtualization and consolidation, effective cooling tactics, and energy management and monitoring, all aimed at reducing energy consumption and enhancing energy performance. Furthermore, the framework emphasizes the significance of incorporating energy-related sustainability metrics into decision-making procedures and adhering to regulatory standards for energy efficiency. Through adherence to this framework, data centres’ environmental impact can be mitigated and a positive contribution towards a sustainable future can be made, particularly in the realm of energy conservation and optimization.
Evaluation of Physicochemical Properties Composite Biodiesel from Waste Cooking Oil and Schleichera oleosa Oil
Authors: Suherman Suherman , Abdullah Ilmi , Sabri Muhammad , Silitonga Arridina Susan
Published: August 2023

Waste cooking oil (WCO) biodiesel has some disadvantages, such as poor cold flow properties, low oxidation stability, and flash point during storage. These poor physicochemical properties can be improved by different ways, such as the addition of non-edible oil. The aim of this study to analyse physicochemical properties of the biodiesel made by between WCO and Schleichera oleosa (SO). The biodiesel produced with 70:30% of WCO and SO respectively as crude oil, further introducing of different KOH-based catalyst into this oil to obtained the methyl ester. The optimum yield transesterification process are 94% with 60 min. of the reaction time, 1 wt.% KOH, and 12:1 molar ratio the methanol to oil. On the other hand, the Schleichera oleosa blend shows oxidation stability at 6.8 h and 3.3 h for Waste cooking oil methyl ester (WCME). The reduction of cold flow and, on the contrary, the flash point increase were obtained with a 70:30% ratio of WCO and SO. The cold flow properties and flash point of the fuel. Thus, mixed WCO and Schleichera oleosa oil improve the physiochemical properties such as oxidation stability, flash point, and cold flow of biodiesel without the need for synthetic antioxidants.
A Simplified Lattice Boltzmann Boundary Conditions for Gas Transport in Self-Affine Microchannels with an Inherent Roughness of in a Tight Reservoir
Authors: Wang Fengjiao , Xu He , Liu Yikun , Hu Chaoyang
Published: August 2023

A simplified method of determining lattice Boltzmann boundary conditions based on self-affine microchannels with an inherent roughness in a tight reservoir is presented in this paper to address nonlinear efficiency problems in fluid simulation. This approach effectively combines the influence of rough surfaces in the simulation of the flow field, the description of L-fractal theory applied to rough surfaces, and a generalized lattice Boltzmann method with equivalent composite slip boundary conditions for inherent roughness. The numerical simulations of gas slippage in a two-dimensional plate model and rough surfaces to induce gas vortex reflux flow are also successfully carried out, and the results are in good agreement with the simulation results, which establishes the reliability and flexibility of the proposed simplified method of rough surfaces. The effects of relative average height and fractal dimensions of the rough surfaces under exact boundary conditions and equivalent coarsened ones are investigated from three perspectives, namely those of the average lattice velocity, the lattice velocity at average height position at the outlet, and the coefficient of variation for lattice velocity at average height position. It was found that the roughness effect on gas flow behavior was more obvious when it was associated with the enhanced rarefaction effect. In addition, the area of gas seepage was reduced, and the gas flow resistance was increased. When the fractal dimension of the wall was about 1.20, it has the greatest impact on the fluid flow law. In addition, excessive roughness of the wall surface tends to lead to vortex backflow of the gas in the region adjacent to the wall, which greatly reduces its flow velocity. For gas flow in the nanoscale seepage space, wall roughness hindered gas migration rate by 84.7%. For pores larger than 200 nm, the effects of wall roughness on gas flow are generally negligible.
A Brief Survey of Paradigmatic Fractals from a Topological Perspective
Authors: Patiño Ortiz Julián , Patiño Ortiz Miguel , Martínez-Cruz Miguel-Ángel , Balankin Alexander S.
Published: August 2023

The key issues in fractal geometry concern scale invariance (self-similarity or self-affinity) and the notion of a fractal dimension D which exceeds the topological dimension d. In this regard, we point out that the constitutive inequality D>d can have either a geometric or topological origin, or both. The main topological features of fractals are their connectedness, connectivity, ramification, and loopiness. We argue that these features can be specified by six basic dimension numbers which are generally independent from each other. However, for many kinds of fractals, the number of independent dimensions may be reduced due to the peculiarities of specific kinds of fractals. Accordingly, we survey the paradigmatic fractals from a topological perspective. Some challenging points are outlined.
Structural Pounding Effect on the Seismic Performance of a Multistorey Reinforced Concrete Frame Structure
Authors: Bantilas Kosmas E. , Naoum Maria C. , Kavvadias Ioannis E. , Karayannis Chris G. , Elenas Anaxagoras
Published: August 2023

During intense ground motion excitations, the pounding between adjacent buildings may result in extensive structural damage. Despite the provision of regulations regarding the minimum separation gap required to prevent structural collisions, the majority of existing structures are poorly separated. The modern seismic design and assessment of structures are based on the definition of acceptable response levels in relation to the intensity of seismic action, which is usually determined by an acceptable probability of exceedance. From this point of view, the seismic performance of a typical eight-storey reinforced concrete (RC) frame structure is evaluated in terms of pounding. In particular, the performance is evaluated using six different separation gap distances as a fraction of the EC8 minimum distance. As the height of the adjacent structure affected the required separation distance, the examined RC structure was assumed to interact with four idealized rigid structures of one to four storeys. The typical storey height was equal between the examined structures; therefore, collision could occur at the diaphragm level. To this end, incidental dynamic analyses (IDAs) were performed, and the fragility curves for different limit states were obtained for each case. Finally, the seismic fragility was combined with the hazard data to evaluate the seismic performance probabilistically.
A New Full-Face Mask for Multifunctional Non-Invasive Ventilation
Authors: Vasconcelos Renata Santos , Nogueira Andréa Nóbrega Cirino , Montenegro Junior Renan Magalhães , Peixoto Junior Arnaldo Aires , Ferreira Lucas Alves , Sousa Carlos Eugênio Moreira , Ricca Diego Eneas Peres , da Silveira Jarbas Aryel Nunes , Ribeiro Fábio Cisne , Cavalcanti Francisco Rodrigo Porto , Lobo Filho José Glauco
Published: August 2023

Background: Noninvasive ventilation (NIV) provides positive pressure through different interfaces. A multifunctional full-face mask prototype was developed to provide NIV from three sources: ICU ventilators, portable ventilators, and high-flow medical gas pipeline systems. This study aimed to evaluate the usability of this prototype mask. Methods: This was a quantitative experimental study, conducted in two phases: the development of a full-face mask prototype NIV interface, and the evaluation of its usability by health professionals (evaluators) using a heuristic approach. The Wolf Mask prototype is a multifunctional full-face mask that makes it possible to deliver positive pressure from three different sources: microprocessor-controlled ICU ventilators, portable ventilators with single-limb circuits, and high-flow medical gas. The evaluation was conducted in three stages: presentation of the prototype to the evaluators; skills testing via simulation in a clinical environment; and a review of skills. Results: The prototype was developed by a multidisciplinary team and patented in Brazil. The evaluators were 10 health professionals specializing in NIV. Seven skills related to handling the prototype were evaluated. Three of the ten evaluators called for (non-urgent) changes to improve recognition of the components of the prototype. Only one evaluator called for (non-urgent) changes to improve recognition of the pieces, assembly, and checking the mask. Conclusions: The newly developed multifunctional full-face mask prototype demonstrated excellent usability for providing noninvasive ventilation from multiple sources. Minor modifications may further improve the design.
Epidemiology and Antimicrobial Resistance Patterns of Urinary Tract Infections: A Cross-Sectional Study from Southwestern Saudi Arabia
Authors: Alhazmi Abdulaziz H. , Alameer Khalid M. , Abuageelah Bandar M. , Alharbi Rena H. , Mobarki Mousa , Musawi Shaqraa , Haddad Moayad , Matabi Abdullatif , Dhayhi Nabil
Published: August 2023

Background: Urinary tract infections (UTIs) are a prevalent form of urinary tract diseases affecting individuals of all ages and genders. In the Kingdom of Saudi Arabia (KSA), UTIs are a significant burden on the healthcare system, comprising 10% of all infections and ranking as the second leading cause of emergency department admissions. Despite this, limited research has been conducted in Saudi Arabia, particularly in Jazan Province, located in the southwestern region. Methods: This retrospective, cross-sectional study encompassed individuals with positive urine cultures who sought care at a tertiary hospital in Jazan between January 2022 and March 2023. A standardized data collection form was utilized to retrieve relevant information from microbiology lab test results and patients’ electronic medical records. Variables such as sex, urine sample collection date, bacterial isolates, antibiotic sensitivity, and resistance were collected using the data collection form. Data were analyzed using SPSS software, version 23.0 (IBM Corp., Armonk, NY, USA). Results: A total of 1082 urinary bacterial samples were isolated and identified. Females accounted for more bacterial infections (62.66%) than males (37.34%). Gram-negative bacteria represented 94% of all isolated strains. The most prevalent pathogens associated with UTIs were Escherichia coli (47.97%), Klebsiella pneumoniae (24.58%), and Pseudomonas aeruginosa (11.55%). Antimicrobial resistance patterns indicated the presence of extended-spectrum beta-lactamase (ESBL) (30.13%), carbapenemase-resistant Enterobacter (CRE) (1.94%), methicillin-resistant Staphylococcus aureus (MRSA) (0.74%), and vancomycin-resistant Enterococci (VRE) (0.18%). UTI incidence demonstrated a higher prevalence in September (13%) compared to other months in 2022. Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa were the predominant Gram-negative multidrug-resistant organisms (MDRO), accounting for 34.42%, 13.95%, and 1.63% of the population. Conclusions: The prevalence of UTIs caused by antibiotic-resistant microbes is notable in Jazan. Consistent with findings from other regions, Escherichia coli remains the most common causative pathogen of UTIs, displaying a seasonal pattern that warrants attention. Approximately 35% of reported cases involve MDRO, with ESBLs accounting for 30%. These results should raise concerns among healthcare officials, highlighting the necessity for further investigations into factors contributing to the circulation of MDRO in Jazan.
Caffeic Acid Phenethyl Ester (CAPE) Synergistically Enhances Paclitaxel Activity in Ovarian Cancer Cells
Authors: Kleczka Anna , Dzik Radosław , Kabała-Dzik Agata
Published: August 2023

Caffeic acid phenethyl ester (CAPE) belongs to the phenols found in propolis. It has already shown strong antiproliferative, cytotoxic and pro-apoptotic activities against head and neck cancers and against breast, colorectal, lung and leukemia cancer cells. Ovarian cancer is one of the most dangerous gynecological cancers. Its treatment involves intensive chemotherapy with platinum salts and paclitaxel (PTX). The purpose of this study was to evaluate whether the combined use of CAPE and paclitaxel increases the effectiveness of chemotherapeutic agents. The experiment was performed on three ovarian cancer lines: OV7, HTB78, and CRL1572. The effect of the tested compounds was assessed using H-E staining, a wound-healing test, MTT and the cell death detection ELISAPLUS test. The experiment proved that very low doses of PTX (10 nM) showed a cytotoxic effect against all the cell lines tested. Also, the selected doses of CAPE had a cytotoxic effect on the tested ovarian cancer cells. An increase in the cytotoxic effect was observed in the OV7 line after the simultaneous administration of 10 nM PTX and 100 µM CAPE. The increase in the cytotoxicity was dependent on the CAPE dosage (50 vs. 100 µM) and on the duration of the experiment. In the other cell lines tested, the cytotoxic effect of PTX did not increase after the CAPE administration. The administration of PTX together with CAPE increased the percentage of apoptotic cells in the tested ovarian cancer cell lines. Moreover, the simultaneous administration of PTX and CAPE enhanced the anti-migration activity of the chemotherapeutic used in this study.
Chemical Composition, Preliminary Toxicity, and Antioxidant Potential of Piper marginatum Sensu Lato Essential Oils and Molecular Modeling Study
Authors: Feitosa Bruna de Souza , Ferreira Oberdan Oliveira , Mali Suraj N. , Anand Amit , Cruz Jorddy Nevez , Franco Celeste de Jesus Pereira , Mahawer Sonu Kumar , Kumar Ravendra , Cascaes Marcia Moraes , Oliveira Mozaniel Santana de , Andrade Eloisa Helena de Aguiar
Published: August 2023

The essential oils (OEs) of the leaves, stems, and spikes of P. marginatum were obtained by hydrodistillation, steam distillation, and simultaneous extraction. The chemical constituents were identified and quantified by GC/MS and GC-FID. The preliminary biological activity was determined by assessing the toxicity of the samples to Artemia salina Leach larvae and calculating the mortality rate and lethal concentration (LC50). The antioxidant activity of the EOs was determined by the DPPH radical scavenging method. Molecular modeling was performed using molecular docking and molecular dynamics, with acetylcholinesterase being the molecular target. The OES yields ranged from 1.49% to 1.83%. The EOs and aromatic constituents of P. marginatum are characterized by the high contents of (E)-isoosmorhizole (19.4–32.9%), 2-methoxy-4,5-methylenedioxypropiophenone (9.0–19.9%), isoosmorhizole (1.6–24.5%), and 2-methoxy-4,5-methylenedioxypropiophenone isomer (1.6–14.3%). The antioxidant potential was significant in the OE of the leaves and stems of P. marginatum extracted by SD in November (84.9 ± 4.0 mg TE·mL−1) and the OEs of the leaves extracted by HD in March (126.8 ± 12.3 mg TE·mL−1). Regarding the preliminary toxicity, the OEs of Pm-SD-L-St-Nov and Pm-HD-L-St-Nov had mortality higher than 80% in concentrations of 25 µg·mL−1. This in silico study on essential oils elucidated the potential mechanism of interaction of the main compounds, which may serve as a basis for advances in this line of research.
Characterization of Activated Carbon from Rice Husk for Enhanced Energy Storage Devices
Authors: Yerdauletov Meir S. , Nazarov Kuanysh , Mukhametuly Bagdaulet , Yeleuov Mukhtar A. , Daulbayev Chingis , Abdulkarimova Roza , Yskakov Almas , Napolskiy Filipp , Krivchenko Victor
Published: August 2023

The production of activated carbon (AC) from lignocellulosic biomass through chemical activation is gaining global attention due to its scalability, economic viability, and environmental advantages. Chemical activation offers several benefits, including energy efficiency, reduced carbonization time, and lower temperature requirements. In this study, potassium hydroxide (KOH) was employed for chemical activation, resulting in activated carbon with a high specific surface area of ~3050 m2/g. The structural analysis revealed the presence of graphitized carbon in the activated carbon matrix, accounting for over 15%. The X-ray diffraction (XRD) technique was employed to investigate the activated carbon derived from rice husk (RH). The potential applications of activated carbon obtained from rice husks through chemical activation were explored, including its use for heavy metal removal, elimination of organic pollutants, and as an active material in hybrid energy storage devices. Furthermore, a scaling methodology for the production of activated carbon was proposed, facilitating its industrial implementation.
Bringing Nitric Oxide to the Molybdenum World—A Personal Perspective
Authors: Maia Luisa B.
Published: August 2023

Molybdenum-containing enzymes of the xanthine oxidase (XO) family are well known to catalyse oxygen atom transfer reactions, with the great majority of the characterised enzymes catalysing the insertion of an oxygen atom into the substrate. Although some family members are known to catalyse the “reverse” reaction, the capability to abstract an oxygen atom from the substrate molecule is not generally recognised for these enzymes. Hence, it was with surprise and scepticism that the “molybdenum community” noticed the reports on the mammalian XO capability to catalyse the oxygen atom abstraction of nitrite to form nitric oxide (NO). The lack of precedent for a molybdenum- (or tungsten) containing nitrite reductase on the nitrogen biogeochemical cycle contributed also to the scepticism. It took several kinetic, spectroscopic and mechanistic studies on enzymes of the XO family and also of sulfite oxidase and DMSO reductase families to finally have wide recognition of the molybdoenzymes’ ability to form NO from nitrite. Herein, integrated in a collection of “personal views” edited by Professor Ralf Mendel, is an overview of my personal journey on the XO and aldehyde oxidase-catalysed nitrite reduction to NO. The main research findings and the path followed to establish XO and AO as competent nitrite reductases are reviewed. The evidence suggesting that these enzymes are probable players of the mammalian NO metabolism is also discussed.
Inhibitory Potential of Different Bilberry (Vaccinium myrtillus L.) Extracts on Human Salivary α-Amylase
Authors: Karcheva-Bahchevanska Diana , Nikolova Mariana , Iliev Ilia
Published: August 2023

Recently, consumer preferences for bilberries have increased markedly. This fact is probably related to their natural constituents, such as phenolic compounds including anthocyanins and tannins, as well as the vitamins and minerals they contain. Phenolic compounds are known for their numerous beneficial effects on human health. Moreover, bilberry fruits have been shown to inhibit the activity of carbohydrate hydrolyzing enzymes, which can significantly decrease the postprandial increase in blood glucose levels. Thus, the aim of the present study is to investigate the inhibitory effect of Vaccinium myrtillus L. extracts on key enzyme α-amylase, linked to type 2 diabetes. No data have been published on the inhibitory properties of Vaccinium myrtillus L. fruits growing wild in Bulgaria against carbohydrate enzymes. Bilberry extracts were analyzed for total polyphenols, total anthocyanin content, antioxidant activity and their inhibitory properties against α-amylase. The contents of flavonols, anthocyanins and stilbenes were determined by HPLC analysis. The identified flavonols in the analyzed bilberry extracts were mainly represented by quercetin derivatives as rutinoside. The predominant anthocyanins for both aqueous and organic solvents were delphinidin-3-galactoside and malvidin-3-glucoside. The results revealed that bilberry extracts are effective inhibitors of α-amylase, with IC50 values from 20.8 to 194.8 μg GAE/mL. All the samples proved to have antioxidant activity measured by three different in vitro assays (FRAP, CUPRAC and DPPH). The inhibitory properties of V. myrtillus L. extracts may provide a new direction in the development and research of new pharmaceuticals for the suppression of postprandial hyperglycemia in diabetic patients.
Spatial Balance of Photogenerated Charge Carriers in Active Layers of Polymer Solar Cells
Authors: Im Chan , Kang Sang Woong , Choi Jeong Yoon , An Jongdeok , Mičová Júlia , Remeš Zdeněk
Published: August 2023

Bulk heterojunction polymer solar cells (PSCs) blended with non-fullerene-type acceptors (NFAs) possess good solar power conversion efficiency and compatibility with flexible electronics, rendering them good candidates for mobile photovoltaic applications. However, their internal absorption performance and mechanism are yet to be fully elucidated because of their complicated interference effect caused by their multilayer device structure. The transfer matrix method (TMM) is ideal for analyzing complex optical electric fields by considering multilayer interference effects. In this study, an active layer (AL) thickness-dependent TMM is used to obtain accurate information on the photon-capturing mechanisms of NFA-based PSCs for comparison with experimental results. Devices with AL thicknesses of 40–350 nm were prepared, and the AL-thickness-dependent device parameters with incident photon-to-current efficiency spectra were compared with the calculated internal absorption spectra of the TMM. The spectrally and spatially resolved spectra as a function of the AL thickness and excitation wavelength revealed that the power conversion efficiency of the NFA-blended PSC decreased with the increasing AL thickness after reaching a maximum of ~100 nm; by contrast, the internal absorption efficiency showed the opposite trend. Furthermore, the TMM spectra indicated that the spatial distribution of the photogenerated charge carriers became significantly imbalanced as the AL thickness increased, implying that the AL-dependent loss stemmed from the discrepancy between the absorption and the extracted charge carriers.
Protective Effects and Mechanisms of Pectolinarin against H2O2-Induced Oxidative Stress in SH-SY5Y Neuronal Cells
Authors: Pang Qi Qi , Kim Ji Hyun , Kim Hyun Young , Kim Ji-Hyun , Cho Eun Ju
Published: August 2023

This study aims to investigate the protective effects and mechanisms of pectolinarin against oxidative stress-induced cell damage in SH-SY5Y cells. Neurodegenerative diseases—such as Alzheimer’s disease—are potentially associated with oxidative stress, which causes excessive production of reactive oxygen species (ROS) that damage DNA and proteins in neuronal cells. The results of this study demonstrate that pectolinarin can scavenge hydroxyl and nitric oxide radicals in a concentration-dependent manner. Moreover, pectolinarin significantly increased cell viability while reducing ROS production and LDH release in the hydrogen peroxide (H2O2)-induced control group. Additionally, Pectolinarin recovered protein expression from H2O2-altered levels back to close-to-normal SH-SY5Y cell levels for components of the oxidative stress, inflammation, and apoptosis pathways—such as nuclear factor erythroid 2-related factor 2 (Nrf2), kelch-like ECH-associated protein (Keap1), anti-heme oxygenase 1 (HO-1), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), B-cell lympho-ma-2 (Bcl-2) protein, and Bcl-2-associated X protein (Bax). These findings suggest that pectolinarin has the potential to be used as a plant material for functional foods to be applied in the treatment of neurodegenerative diseases, such as Alzheimer’s disease, by mitigating oxidative stress-induced damage to neuronal cells.
The Copper(II)-Thiodiacetate (tda) Chelate as Efficient Receptor of N9-(2-Hydroxyethyl)Adenine (9heade): Synthesis, Molecular and Crystal Structures, Physical Properties and DFT Calculations of [Cu(tda)(9heade)(H2O)]·2H2O
Authors: Rosales-Martínez Carmen , Matilla-Hernádez Antonio , Choquesillo-Lazarte Duane , Frontera Antonio , Castiñeiras Alfonso , Niclós-Gutiérrez Juan
Published: August 2023

Considering that Cu(tda) chelate (tda: dithioacetate) is a receptor for adenine and related 6-aminopurines, this study reports on the synthesis, molecular and crystal structures, thermal stability, spectral properties and DFT calculations related to [Cu(tda)(9heade)(H2O)]·2H2O (1) [9heade: N9-(2-hydroxyethyl)adenine]. Concerning the molecular recognition of (metal chelate)-(adenine synthetic nucleoside), 1 represents an unprecedented metal binding pattern (MBP) for 9heade. However, unprecedentedly, the Cu(tda)-9heade molecular recognition in 1 is essentially featured in the Cu-N1(9heade) bond, without any N6-H⋯O(carboxyl tda) interligand interaction. Nevertheless, N1 being the most basic donor for N9-substituted adenines, this Cu-N1 bond is now assisted by an O2–water-mediated interaction (N6-H⋯O2 and O2⋯Cu weak contact). Also, in the crystal packing, the O-H(ol) of 9heade interacts with its own adenine moiety as a result of an O3–water-mediated interaction (O(ol)-H⋯O3 plus O3-H36⋯π(adenine moiety)). Both water-mediated interactions seem to be responsible for serious alterations in the physical properties of crystalline or grounded samples. Density functional theory calculations were used to evaluate the interactions energetically. Moreover, the quantum theory of atoms-in-molecules (QTAIM), in combination with the noncovalent interaction plot (NCIPlot), was used to analyze the interactions and rationalize the existence and relative importance of hydrogen bonding, chalcogen bonding and π-stacking interactions. The novelty of this work resides in the discovery of a novel binding mode for N9-(2-hydroxyethyl)adenine. Moreover, the investigation of the important role of water in the solid state of 1 is also relevant, along with the chalcogen bonding interactions demonstrated by the density functional theory (DFT) study.
Synthesis of Functionalized 3H-pyrrolo-[1,2,3-de] Quinoxalines via Gold-Catalyzed Intramolecular Hydroamination of Alkynes
Authors: Iazzetti Antonia , Fabrizi Giancarlo , Goggiamani Antonella , Marrone Federico , Sferrazza Alessio , Ullah Karim
Published: August 2023

A gold-catalyzed protocol to obtain functionalized 3H-pyrrolo [1,2,3-de] quinoxalines from suitable substituted N-alkynyl indoles has been proposed. The mild reaction conditions were revealed to be compatible with different functional groups, including halogen, alkoxyl, cyano, ketone, and ester, allowing the isolation of title compounds with yields from good to high. A reaction mechanism has been proposed, and theoretical calculations have been provided to rationalize the final step of the hypothesized reaction mechanism. As quinoxaline-containing polycyclic compounds, this class of molecules may represent a valuable template in medicinal chemistry and material science.
[IPr#–PEPPSI]: A Well-Defined, Highly Hindered and Broadly Applicable Pd(II)–NHC (NHC = N-Heterocyclic Carbene) Precatalyst for Cross-Coupling Reactions
Authors: Rahman Md. Mahbubur , Zhao Qun , Meng Guangrong , Lalancette Roger , Szostak Roman , Szostak Michal
Published: August 2023

In this Special Issue, “Featured Papers in Organometallic Chemistry”, we report on the synthesis and characterization of [IPr#–PEPPSI], a new, well-defined, highly hindered Pd(II)–NHC precatalyst for cross-coupling reactions. This catalyst was commercialized in collaboration with MilliporeSigma, Burlington, ON, Canada (no. 925489) to provide academic and industrial researchers with broad access to reaction screening and optimization. The broad activity of [IPr#–PEPPSI] in cross-coupling reactions in a range of bond activations with C–N, C–O, C–Cl, C–Br, C–S and C–H cleavage is presented. A comprehensive evaluation of the steric and electronic properties is provided. Easy access to the [IPr#–PEPPSI] class of precatalysts based on modular pyridine ligands, together with the steric impact of the IPr# peralkylation framework, will facilitate the implementation of well-defined, air- and moisture-stable Pd(II)–NHC precatalysts in chemistry research.