bluuebunny/crossref_metadata_2025 huggingface dataset:
From GPT-3.5 to GPT-4.o: A Leap in AI’s Medical Exam Performance
Authors: Kipp Markus
Published: September 2024

ChatGPT is a large language model trained on increasingly large datasets to perform diverse language-based tasks. It is capable of answering multiple-choice questions, such as those posed by diverse medical examinations. ChatGPT has been generating considerable attention in both academic and non-academic domains in recent months. In this study, we aimed to assess GPT’s performance on anatomical multiple-choice questions retrieved from medical licensing examinations in Germany. Two different versions were compared. GPT-3.5 demonstrated moderate accuracy, correctly answering 60–64% of questions from the autumn 2022 and spring 2021 exams. In contrast, GPT-4.o showed significant improvement, achieving 93% accuracy on the autumn 2022 exam and 100% on the spring 2021 exam. When tested on 30 unique questions not available online, GPT-4.o maintained a 96% accuracy rate. Furthermore, GPT-4.o consistently outperformed medical students across six state exams, with a statistically significant mean score of 95.54% compared with the students’ 72.15%. The study demonstrates that GPT-4.o outperforms both its predecessor, GPT-3.5, and a cohort of medical students, indicating its potential as a powerful tool in medical education and assessment. This improvement highlights the rapid evolution of LLMs and suggests that AI could play an increasingly important role in supporting and enhancing medical training, potentially offering supplementary resources for students and professionals. However, further research is needed to assess the limitations and practical applications of such AI systems in real-world medical practice.
Language Differences in Online Complaint Responses between Generative Artificial Intelligence and Hotel Managers
Authors: Wan Yau-Ni
Published: September 2024

Since November 2022, the use of generative artificial intelligence (GAI) technology has increased in many customer service industries. However, little is known about AI’s language choices and meaning-making resources compared to human responses from a systematic linguistic point of view. The present study is a discourse analysis that explores negative online guest complaints made to four luxury heritage hotels in Hong Kong that are classified as cultural heritage sites with rich interpersonal and historical values. We collected authentic guest complaints and responses from hotel managers from April 2012 to October 2022 in online travel forums, and then had GAI draft response letters on behalf of the hotel managers. Our total dataset was 65,539 words and consisted of three subcorpora: guest complaints (Text a of 115 complaints totaling 26,224 words), hotel manager responses (Text b of 115 response letters totaling 14,975 words), and AI-generated responses (Text c of 115 response letters totaling 24,340 words). This study used systemic functional linguistics to explore interpersonal meanings in texts; for example, appraisal resources, verb processes, and personal pronouns were compared between texts. First, we identified the most frequent words of the common themes across the three subcorpora and found significant differences in lexicogrammatical features between hotel managers and AI-generated responses using the log-likelihood ratio. The results suggest that AI-generated texts are able to provide a tailored and empathetic response to guests, but hotel managers may need to introduce some modifications, such as time indicators, sensory verbs used, and complimentary offers. This study explores the differences in word choices and communication strategies, which have implications and insights for the hospitality industry, especially luxury heritage hotels where caring and personalized customer service are considered important.
ZnO and ZnO/Ce Powders as Tribocatalysts for Removal of Tetracycline Antibiotic
Authors: Ivanova Dobrina , Kolev Hristo , Stefanov Bozhidar I. , Kaneva Nina
Published: September 2024

Research on tribocatalysis, which involves the triboelectric effect, is based on the concept that friction between dissimilar materials can generate charges capable of initiating catalytic reactions. This phenomenon holds significant potential for the degradation of wastewater contaminants in the environment. In this study, pure and Ce-modified (2 mol%) ZnO powders were investigated as tribocatalysts for the degradation of doxycycline (DC), a tetracycline antibiotic, in the absence of light. The research demonstrates that friction between the catalyst, the beaker, and the polytetrafluoroethylene (PTFE) magnetic rod induces charge transfer at their interfaces, leading to the breakdown of pollutants. Additionally, doxycycline degradation was observed at three different stirring speeds (100, 300, and 500 rpm). The results confirmed the tribocatalytic effect, showing that DC degradation increases with higher stirring speeds. Using ZnO and ZnO/Ce powders, maximum degradations of 80% and 55%, respectively, were achieved in 24 h at a stirring speed of 500 rpm. The findings of this study suggest that these samples can effectively degrade contaminants in water through the application of mechanical energy.
Exploring the Inhibitory Efficacy of Resokaempferol and Tectochrysin on PI3Kα Protein by Combining DFT and Molecular Docking against Wild-Type and H1047R Mutant Forms
Authors: Paraschiv Cristina , Gosav Steluța , Burlacu Catalina Mercedes , Praisler Mirela
Published: September 2024

This study explores the inhibitory potential of the flavonoids resokaempferol and tectochrysin against both wild-type and H1047R mutant forms of PI3Kα, aiming to expand the repertoire of targeted cancer therapies. Employing an array of computational techniques, including Density Functional Theory (DFT), calculations of electronic parameters such as the energies of the frontier molecular orbitals, Molecular Electrostatic Potential (MEP) mapping, and Molecular Docking, we investigate in detail the molecular interactions of these compounds with the PI3Kα kinase. Our findings, corroborated by DFT calculations performed based on the B3LYP (Becke, three-parameter, Lee-Yang-Parr) hybrid functional and the 6-311G++(d,p) basis set, align well with experimental benchmarks and indicate substantial inhibitory efficacy. Further analysis of chemical potential and bioavailability confirmed the drug-like attributes of these flavonoids. Binding affinity and selectivity were rigorously assessed through self-docking and cross-docking against the PIK3CA PDB structures 7K71 and 8TS9. The most promising interactions were validated using Pairwise Structure Alignment and MolProbity analysis of all-atom contacts and geometry. Collectively, these results highlight the flavonoids’ potential as PI3Kα inhibitors and exemplify the utility of natural compounds in the development of precise anticancer treatments.
Investigation of the Clinical Value of Four Visualization Modalities for Congenital Heart Disease
Authors: Lee Shen-yuan , Squelch Andrew , Sun Zhonghua
Published: September 2024

Diagnosing congenital heart disease (CHD) remains challenging because of its complex morphology. Representing the intricate structures of CHD on conventional two-dimensional flat screens is difficult owing to wide variations in the pathologies. Technological advancements, such as three-dimensional-printed heart models (3DPHMs) and virtual reality (VR), could potentially address the limitations of viewing complex structures using conventional methods. This study aimed to investigate the usefulness and clinical value of four visualization modalities across three different cases of CHD, including ventricular septal defect, double-outlet right ventricle, and tetralogy of Fallot. Seventeen cardiac specialists were invited to participate in this study, which was aimed at assessing the usefulness and clinical value of four visualization modalities, namely, digital imaging and communications in medicine (DICOM) images, 3DPHM, VR, and 3D portable document format (PDF). Out of these modalities, 76.4% of the specialists ranked VR as the best for understanding the spatial associations between cardiac structures and for presurgical planning. Meanwhile, 94.1% ranked 3DPHM as the best modality for communicating with patients and their families. Of the various visualization modalities, VR was the best tool for assessing anatomical locations and vessels, comprehending the spatial relationships between cardiac structures, and presurgical planning. The 3DPHM models were the best tool for medical education as well as communication. In summary, both 3DPHM and VR have their own advantages and outperform the other two modalities, i.e., DICOM images and 3D PDF, in terms of visualizing and managing CHD.
The Impact of a Multidisciplinary Team Conference on Non-Small Cell Lung Cancer Care: Time Barriers and Long-Term Outcomes
Authors: Saeteng Somcharoen , Chewaskulyong Busyamas , Charoentum Chaiyut , Lertprasertsuke Nirush , Euathrongchit Juntima , Tajarernmuang Pattraporn , Klunklin Pitchayaponne , Siwachat Sophon , Kongkarnka Sarawut , Wannasopha Yutthaphan , Suksombooncharoen Thatthan , Ketpueak Thanika , Tantraworasin Apichat
Published: September 2024

Background/Objectives: The prolonged time to reach investigation and management decisions in non-small cell lung cancer (NSCLC) patients can negatively impact long-term outcomes. This retrospective cohort study aims to assess the impact of a multidisciplinary team conference (MDT) on NSCLC care quality and outcomes. Methods: This retrospective study included resectable NSCLC patients who underwent pulmonary resection at Chiang Mai University Hospital, Thailand, from 1 January 2009 to 31 December 2021. Patients were divided into two groups: non-MDT and MDT groups, based on the initiation of MDT on 1 March 2018. The study compared overall survival, disease-free survival, and waiting times for investigation and surgery between the two groups. The effect of MDT on these outcomes was analyzed using multivariable analysis with inverse-probability weighting propensity scores. Results: The study included 859 patients, with 583 in the non-MDT group and 276 in the MDT group. MDT groups had a higher proportion of stage I and II NSCLC patients undergoing pulmonary resection (78.6% vs. 59.69%, p < 0.001). In multivariable analysis, patients in the MDT group had a significantly higher likelihood of longer survival compared to the non-MDT group (adjusted HR 0.23, 95% CI 0.09–0.55). Median waiting times for bronchoscopy (3 days vs. 12 days, p = 0.012), pathologic report (7 days vs. 13 days, p < 0.001), and surgery scheduling (18 days vs. 25 days, p = 0.001) were significantly shorter in the MDT group. Conclusions: An MDT has a survival benefit in NSCLC care and improves waiting times for investigation and treatment steps. Further studies are needed to validate these results.
Healing Potential of the Marine Polysaccharides Carrageenan and Ulvan on Second-Degree Burns
Authors: Statha Dimitra , Papaioannou Asimina , Kikionis Stefanos , Kostaki Maria , Sfiniadakis Ioannis , Vitsos Andreas , Anastassopoulou Jane , Ioannou Efstathia , Roussis Vassilios , Rallis Michail Christou
Published: September 2024

The treatment of second-degree burn wounds presents a significant clinical challenge, often characterized by prolonged healing times and risk of complications. In this study, the wound healing potential of bioactive marine sulfated polysaccharides ulvan and carrageenan formulated in gels at concentrations of 1.5%, 5.0%, and 10% w/w was evaluated. Hairless female SKH-hr2 mice (n = 7 per treatment) with burn-inflamed skin were treated with the polysaccharide-based gels, and the therapeutic efficacy was assessed using a comprehensive array of evaluation methods, including a histopathological analysis, clinical observation, photo-documentation, an image analysis, an evaluation of biophysical skin parameters, and FT-IR spectroscopy. Our findings indicate that the 10% w/w carrageenan gel exhibited significant enhancement in wound healing, particularly in the early stages of the healing process. This was evidenced by the restoration of the α-helix structure of collagen and the configuration of glycosaminoglycans, as demonstrated by FT-IR absorption bands of the skin both in vivo and ex vivo. Furthermore, the 5% w/w ulvan gel also demonstrated notable efficacy in promoting wound healing, particularly in the later stages of the healing process. These results suggest that carrageenan and ulvan gels hold promise for improving the efficiency of wound healing in second-degree burn wounds. Our study contributes to the understanding of the therapeutic potential of marine polysaccharides and provides insights into their mechanism of action in promoting wound healing.
DNA Barcoding and Intronic-ORF Structure Analyses of Cultivated Pyropia yezoensis in China: The Genetic Impact under Climate Change
Authors: Huang Guihua , Tian Cuicui , Wei Liangdi , Hu Chuanming , Xu Guangping , Zhou Wei , Deng Yinyin
Published: September 2024

Pyropia yezoensis is the most widely cultivated and economically important alga. Affected by climate change, the cultivation of P. yezoensis has gradually migrated to the northern coast of China, increasing from 6.8% in 2019 to 19.5% in 2023. To date, the genetic impact of northern migration on cultivation resources has not been assessed and analyzed extensively. Here, DNA barcoding (rbcL and cox1) and the presence/absence of intronic-ORFs in mitochondrial regions (rnl and cox1) were applied to investigate genetic diversity in 44 P. yezoensis specimens from 17 aquaculture farms in China, with comparisons to Korean and Japanese cultivated resources. The lower intraspecific variation was 0.31% for the cox1 gene and 0.14% for the rbcL gene, with three haplotypes, indicating that intensive selection and breeding during cultivation had narrowed the germplasm genetic variation. The intron structure of mitochondrial regions showed that the cultivated resources had 17 phenotypes, and the northern specimens shared 35.3% of genotypes with the southern specimens, indicating that the cultivated P. yezoensis is expanding its cultivation ranges through north migration. Even with lower genetic diversity, the northern area of cultivation had already developed 17.6% site-specific specimens. The genetic diversity of cultivated P. yezoensis from the Northwest Pacific is also discussed. Our work provides a preliminary framework for P. yezoensis breeding and cultivation under climate change.
Regional Sea Level Changes in the East China Sea from 1993 to 2020 Based on Satellite Altimetry
Authors: Xiong Lujie , Wang Fengwei , Jiao Yanping
Published: September 2024

A comprehensive analysis was carried out to investigate the driving factors and influencing mechanisms of spatiotemporal variation of sea level at multiple scales in the East China Sea (ECS) via satellite altimetry datasets from 1993 to 2020. Based on the altimetry grid data processed by the local mean decomposition method, the spatiotemporal changes of ECS sea level are analyzed from the multi-scale perspective in terms of multi-year, seasonal, interannual, and multi-modal scales. The results revealed that the ECS regional mean sea level change rate is 3.41 ± 0.58 mm/year over the 28-year period. On the seasonal scale, the regional mean sea level change rates are 3.45 ± 0.66 mm/year, 3.35 ± 0.60 mm/year, 3.39 ± 0.71 mm/year, and 3.57 ± 0.75 mm/year, for the four seasons (i.e., spring, summer, autumn, and winter) respectively. The spatial distribution analysis showed that ECS sea level changes are most pronounced in coastal areas. The northeast sea area of Taiwan and the edge of the East China Sea shelf are important areas of mesoscale eddy activity, which have an important impact on regional sea level change. The ECS seasonal sea level change is mainly affected by monsoons, precipitation, and temperature changes. The spatial distribution analysis indicated that the impact factors, including seawater thermal expansion, monsoons, ENSO, and the Kuroshio Current, dominated the ECS seasonal sea level change. Additionally, the ENSO and Kuroshio Current collectively affect the spatial distribution characteristics. Additionally, the empirical orthogonal function was employed to analyze the three modes of ECS regional sea level change, with the first three modes contributing 26.37%, 12.32%, and 10.47%, respectively. Spatially, the first mode mainly corresponds to ENSO index, whereas the second and third modes are linked to seasonal factors, and exhibit antiphase effects. The analyzed correlations between the ECS sea level change and southern oscillation index (SOI), revealed the consistent spatial characteristics between the regions affected by ENSO and those by the Kuroshio Current.
Improved D* Lite Algorithm for Ship Route Planning
Authors: Li Yuankui , Yang Fang , Zhang Xinyu , Yu Dongye , Yang Xuefeng
Published: September 2024

To address the issue of intelligent ship route planning, a ship planning method based on the improved D* Lite algorithm is proposed. Firstly, a navigation environment grid map is constructed using the acquired meteorological and hydrological datasets. The grids are divided into navigable and non-navigable according to navigation requirements, and a route planning model is built. Secondly, the heuristic function and the path function of the D* Lite algorithm are improved. The heuristic function is optimized and weighted, and a risk factor is introduced into the path function to enhance efficiency of path planning while maintaining a safe distance between the planned route and obstacles. Finally, by dynamically adjusting the search step length and the selectable directions of the D* Lite algorithm, the number of waypoints is reduced, and the voyage of the planned route is shortened, resulting in a smooth and collision-free route of ships. The effectiveness of the proposed algorithm is verified through three sets of simulation experiments. The simulation results show that the proposed method in this paper is more suitable for ship route planning and ship maneuvering in practice and can effectively avoid non-navigable grids while optimizing path length, path smoothness, and computation time, making the routes more aligned with actual navigation tasks.
Occurrence Mechanism and Controlling Factors of Shale Oil from the Paleogene Kongdian Formation in Cangdong Sag, Bohai Bay Basin, East China
Authors: Ma Binyu , Hu Qinhong , Pu Xiugang , Yang Shengyu , Wang Xuyang , Han Wenzhong , Wen Jiacheng
Published: September 2024

Free oil, rather than adsorbed oil, is the main contributor to shale oil production with current development technologies, and assessing oil contents in different occurrence states (adsorbed oil vs. free oil) is a critical component in evaluating the economics of shale wells and plays. Although various methodologies have been developed, there are still some fundamental issues in assessing the oil contents in different occurrence states in shale. In this study, a new method was developed to estimate the adsorbed and free oil contents in the Second Member of the Eocene Kongdian Formation (Ek2) shales in Cangdong Sag, Bohai Bay Basin. This method combines the results of standard Rock-Eval pyrolysis and multi-step Rock-Eval pyrolysis with thin section petrography, X-ray diffraction for mineralogy, total organic carbon analyses, field emission scanning electron microscopy for pore morphology, and pore structure analyses by nitrogen physisorption and mercury intrusion porosimetry. Nine lithofacies were identified in a total of 50 shale samples, and the results show that the adsorbed and free oil are mainly contained in pores with diameters > 20 nm, and their contents are mainly controlled by organic matter abundance and thermal maturity of shales. While pore space volume influences the storage of shale oil, it is not a major determinant. Models of shale oil occurrence and its evolution are proposed, suggesting that the high S1 contents of organic-rich and -fair shales, which the latter resulted from oil migration, are the most favorable exploration targets of Ek2 shales. The findings of this study will help prioritize shale oil exploration targets in Ek2 shales.
Comparative Genomics of Fungi in Nectriaceae Reveals Their Environmental Adaptation and Conservation Strategies
Authors: Rissi Daniel Vasconcelos , Ijaz Maham , Baschien Christiane
Published: September 2024

This study presents the first genome assembly of the freshwater saprobe fungus Neonectria lugdunensis and a comprehensive phylogenomics analysis of the Nectriaceae family, examining genomic traits according to fungal lifestyles. The Nectriaceae family, one of the largest in Hypocreales, includes fungi with significant ecological roles and economic importance as plant pathogens, endophytes, and saprobes. The phylogenomics analysis identified 2684 single-copy orthologs, providing a robust evolutionary framework for the Nectriaceae family. We analyzed the genomic characteristics of 17 Nectriaceae genomes, focusing on their carbohydrate-active enzymes (CAZymes), biosynthetic gene clusters (BGCs), and adaptations to environmental temperatures. Our results highlight the adaptation mechanisms of N. lugdunensis, emphasizing its capabilities for plant litter degradation and enzyme activity in varying temperatures. The comparative genomics of different Nectriaceae lifestyles revealed significant differences in genome size, gene content, repetitive elements, and secondary metabolite production. Endophytes exhibited larger genomes, more effector proteins, and BGCs, while plant pathogens had higher thermo-adapted protein counts, suggesting greater resilience to global warming. In contrast, the freshwater saprobe shows less adaptation to warmer temperatures and is important for conservation goals. This study underscores the importance of understanding fungal genomic adaptations to predict ecosystem impacts and conservation targets in the face of climate change.
Epidemiology of Onychomycosis in the United States Characterized Using Molecular Methods, 2015–2024
Authors: Gupta Aditya K. , Wang Tong , Polla Ravi Shruthi , Mann Avantika , Lincoln Sara A. , Foreman Hui-Chen , Bakotic Wayne L.
Published: September 2024

Onychomycosis is a recalcitrant fungal infection of the nail unit that can lead to secondary infections and foot complications. Accurate pathogen identification by confirmatory testing is recommended to improve treatment outcomes. In this study, we reviewed the records of 710,541 patients whose nail specimens were sent to a single molecular diagnostic laboratory between 2015 and 2024. PCR testing revealed a more comprehensive spectrum of pathogens than previously reported, which was corroborated by the demonstration of fungal invasion on histopathology. Consistent with our current understanding, the T. rubrum complex (54.3%) are among the most common pathogens; however, a significant portion of mycology-confirmed diagnoses were caused by the T. mentagrophytes complex (6.5%), Aspergillus (7.0%) and Fusarium (4.5%). Females were significantly more likely to be infected with non-dermatophytes molds (NDMs; OR: 2.0), including Aspergillus (OR: 3.3) and Fusarium (OR: 2.0), and yeasts (OR: 1.5), including Candida albicans (OR: 2.0) and C. parapsilosis (OR 1.6), than males. The T. mentagrophytes complex became more prevalent with age, and conversely the T. rubrum complex became less prevalent with age. Patients aged ≥65 years also demonstrated a higher likelihood of contracting onychomycosis caused by NDMs (OR: 1.6), including Aspergillus (OR: 2.2), Acremonium (OR: 3.5), Scopulariopsis (OR: 2.9), Neoscytalidium (OR: 3.8), and yeasts (OR: 1.8), including C. albicans (OR: 1.9) and C. parapsilosis (OR: 1.7), than young adults. NDMs (e.g., Aspergillus and Fusarium) and yeasts were, overall, more likely to cause superficial onychomycosis and less likely to cause dystrophic onychomycosis than dermatophytes. With regards to subungual onychomycosis, Aspergillus, Scopulariopsis and Neoscytalidium had a similar likelihood as dermatophytes. The advent of molecular diagnostics enabling a timely and accurate pathogen identification can better inform healthcare providers of appropriate treatment selections and develop evidence-based recommendations.
Capturing Tail Risks in Cryptomarkets: A New Systemic Risk Approach
Authors: Barkai Itai , Hadad Elroi , Shushi Tomer , Yosef Rami
Published: September 2024

Using daily returns of Bitcoin, Litecoin, Ripple and Stellar, we introduce a novel risk measure for quantitative-risk management in the cryptomarket that accounts for the significant co-movements between cryptocurrencies. We find that our model has a lower error margin when forecasting the extent of future losses than traditional risk measures, such as Value-at-Risk and Expected Shortfall. Most notably, we observe this in Litecoin’s results, where Expected Shortfall, on average, overestimates the potential fall in the price of Litecoin by 8.61% and underestimates it by 3.92% more than our model. This research shows that traditional risk measures, while not necessarily inappropriate, are imperfect and incomplete representations of risk when it comes to the cryptomarket. Our model provides a suitable alternative for risk managers, who prioritize lower error margins over failure rates, and highlights the value in exploring how risk measures that incorporate the unique characteristics of cryptocurrencies can be used to supplement and complement traditional risk measures.
Climate-Related Regulations and Financial Markets: A Meta-Analytic Literature Review
Authors: Ho Linh Tu , Gan Christopher , Zhao Zhenzhen
Published: September 2024

Countries are confronting climate change using climate-related regulations that require firms and investors to disclose their green strategies and activities. Using the Meta-Analysis Structural Equation Modeling (MASEM) technique, this study evaluates the relationship between climate-related regulations and financial markets. The meta-regression analysis is conducted based on the outcomes of 52 empirical studies screened from 143 relevant articles. The results show the predictive power of the climate-related disclosure (CRD) laws and environmental regulations (ERs) on financial performance across all studies. ERs create mixed impacts on the equity market and support the debt market. Firm value is affected by ERs either negatively or positively. Methodologies and risk-related factors (market, industry, and firm risks) are important in explaining the relationships between ER/CRD and financial performance. The more developed the market, the less the impact of ERs and CRD on the equity market. Considering industry risk is recommended because different industries are exposed to changes in policies differently. The ER/CRD–firm value relationship is affected by all market, industry, and firm risks. The downside effect of mandatory CRD on the equity market suggests that policy makers, firms, and investors should be cautious in passing a new CRD regulation for transformation towards a sustainable economy.
A Sister Species for the Blue Crab, Callinectes sapidus? A Tale Revealed by Mitochondrial DNA
Authors: Locci Chiara , Azzena Ilenia , Pascale Noemi , Ciccozzi Alessandra , Deplano Ilaria , Giantsis Ioannis A. , Papadopoulos Dimitrios K. , Lattos Athanasios , Orrù Flavio , Puzzi Cesare M. , Scarpa Fabio , Casu Marco , Sanna Daria
Published: September 2024

The Atlantic blue crab, Callinectes sapidus, is acknowledged as one of the worst invasive alien species in the Mediterranean, impacting biodiversity and human activities. Native to the western Atlantic, it has expanded to European coastal waters since the early 1900s. Despite its ecological and commercial importance, genetic research on this species is limited. Here we show a comprehensive investigation of the genetic variation and evolutionary history in Callinectes sapidus using 667 mitochondrial COI gene sequences. Our dataset encompasses 36 newly generated sequences from previously understudied Mediterranean sites and 631 from worldwide locations obtained from the GenBank public database. Our findings reveal two distinct, but closely related, genetic groups within the species’ distribution range, suggesting the occurrence of a potential species complex. Furthermore, in the Mediterranean, low levels of genetic variability were observed except for substantial haplotypic differentiation in Turkish samples. This study depicts the global genetic diversity and evolutionary patterns of Callinectes sapidus, offering new insights into the taxonomic status of the species.
Deposition of CdSe Nanocrystals in Highly Porous SiO2 Matrices—In Situ Growth vs. Infiltration Methods
Authors: Baruah Raktim , Dilshad Munira , Diegel Marco , Dellith Jan , Plentz Jonathan , Undisz Andreas , Szeghalmi Adriana , Wächtler Maria
Published: September 2024

Embedding quantum dots into porous matrices is a very beneficial approach for generating hybrid nanostructures with unique properties. In this contribution we explore strategies to dope nanoporous SiO2 thin films made by atomic layer deposition and selective wet chemical etching with precise control over pore size with CdSe quantum dots. Two distinct strategies were employed for quantum dot deposition: in situ growth of CdSe nanocrystals within the porous matrix via successive ionic layer adsorption reaction, and infiltration of pre-synthesized quantum dots. To address the impact of pore size, layers with 10 nm and 30 nm maximum pore diameter were used as the matrix. Our results show that though small pores are potentially accessible for the in situ approach, this strategy lacks controllability over the nanocrystal quality and size distribution. To dope layers with high-quality quantum dots with well-defined size distribution and optical properties, infiltration of preformed quantum dots is much more promising. It was observed that due to higher pore volume, 30 nm porous silica shows higher loading after treatment than the 10 nm porous silica matrix. This can be related to a better accessibility of the pores with higher pore size. The amount of infiltrated quantum dots can be influenced via drop-casting of additional solvents on a pre-drop-casted porous matrix as well as via varying the soaking time of a porous matrix in a quantum dot solution. Luminescent quantum dots deposited via this strategy keep their luminescent properties, and the resulting thin films with immobilized quantum dots are suited for integration into optoelectronic devices.
Enhancement of Wear and Corrosion Resistance of Ti6Al4V Alloy through Hollow Cathode Discharge-Assisted Plasma Nitriding
Authors: Shen Hongyu , Wang Liang
Published: September 2024

In order to improve the wear and corrosion resistance of Ti6Al4V alloy, a Ti-N compound layer was formed on the alloy by plasma nitriding at a relatively low temperature (750 °C) and within an economical processing duration (4 h), in a mixture of NH3 and N2 gases with varying ratios. The influence of the gas mixture on the microstructure, phase composition, and properties of the Ti-N layer was investigated. The results indicated that the thickness of the nitrided layer achieved in a mixed atmosphere with optimal proportions of NH3 and N2 (with a ratio of 1:2) was substantially greater than that obtained in an atmosphere of pure NH3. This suggests that appropriately increasing the proportion of N2 in the nitriding atmosphere is beneficial for the growth of the nitrided layer. The experiments demonstrated that the formation of the surface nitrided layer significantly enhances the corrosion and wear resistance of the titanium alloys.
An Innovative Design for Cleansing, Deodorization, and Pest Control in Drain Covers: Application of the TRIZ Method and Human Factors Engineering
Authors: Yao Kai-Chao , Chen Li-Yun , Li Kuo-Yi , Chang Ya-Nan , Xu Jing-Ran , Huang Wei-Lun , Ho Wei-Sho
Published: September 2024

This study explored an innovative design of a drain cover for dirt removal, deodorization, and pest control. The research methods used in this study included an analysis of the literature, the TRIZ method and general design, and application of human factors engineering. Firstly, the contradiction matrix of the TRIZ method was used to find out the corresponding principles of invention for analysis. Based on the reference of the most innovative design, a drainage cover with rapid cleansing, deodorization, insect-repellent properties, and quick return was designed, and universal design was used to make the drainage cover. The innovative design can be more widely used to allow users to interact with the environment and products more harmoniously, and the innovative design of the drainage cover was faster and more hygienic through the human–computer interaction in the project. Additionally, the design was validated through analyses using the IPA and Kano models, confirming that it met the users’ requirements and expectations. The prototype’s structure was drawn by Autodesk Inventor drawing software (2024). The research results are as follows. We designed a sliding groove and the sliding block on the drainage cover so that the drainage cover could achieve the effect of rapid cleansing by sliding the sliding block. In terms of the odor control and pest prevention, we designed the odor-resistant block and the water filter under the drain cover so that the odor below the drain would not float upwards. And the pests in the drain hole cannot climb out. In terms of the improved operational design, the sliding block could be quickly returned and the use of the pushing aid to not touch the dirt. The successful development of the product validated the effectiveness of this research method for innovative product design and suggests its applicability for the development of other products.
An Investigation into the Optimal Dimple Geometry in a Single-Dimple Sliding Contact
Authors: Scharf Raphael , Pusterhofer Michael , Gussmagg Jakob , Grün Florian
Published: September 2024

This study analyzes the influence of nine distinct texture geometries on a convergent oil film gap using a simulation model. The geometrical dimensions of the textures are characterized by the texture area density, Stex.,A and the ratio of the textured-to-untextured area (Atex./A0). The results show that different texture geometries optimize the tribological performance depending on the value of Stex.,A. Rectangular textures with variable widths (85% of the texture length atex.) significantly enhance lifting and the drag force across a broad range of Stex.,A. Furthermore, rectangular textures with a constant width (85% of the global width b0) show the best improvement within this study. The investigation also reveals that a small texture pitch angle, αtex, further enhances tribological performance.
Image Noise Reduction and Solution of Unconstrained Minimization Problems via New Conjugate Gradient Methods
Authors: Hassan Bassim A. , Moghrabi Issam A. R. , Ameen Thaair A. , Sulaiman Ranen M. , Sulaiman Ibrahim Mohammed
Published: September 2024

The conjugate gradient (CG) directions are among the important components of the CG algorithms. These directions have proven their effectiveness in many applications—more specifically, in image processing due to their low memory requirements. In this study, we derived a new conjugate gradient coefficient based on the famous quadratic model. The derived algorithm is distinguished by its global convergence and essential descent properties, ensuring robust performance across diverse scenarios. Extensive numerical testing on image restoration and unconstrained optimization problems have demonstrated that the new formulas significantly outperform existing methods. Specifically, the proposed conjugate gradient scheme has shown superior performance compared to the traditional Fletcher–Reeves (FR) conjugate gradient method. This advancement not only enhances computational efficiency on unconstrained optimization problems, but also improves the accuracy and quality of image restoration, making it a highly valuable tool in the field of computational imaging and optimization.
Existence Results for Nonlinear Impulsive System with Causal Operators
Authors: Wang Wenli , Bao Junyan
Published: September 2024

In this paper, we establish sufficient conditions for some existence results for nonlinear impulsive differential equations involving causal operators. Our method is based on the monotone iterative technique, a new differential inequality, and the Schauder fixed point theorem. Moreover, we consider three impulsive differential equations as applications to verify our theoretical results.
The Cytochalasins and Polyketides from a Mangrove Endophytic Fungus Xylaria arbuscula QYF
Authors: Tan Qi , Ye Xinyu , Fu Siqi , Yin Yihao , Liu Yufeng , Wu Jianying , Cao Fei , Wang Bo , Zhu Tingshun , Yang Wencong , She Zhigang
Published: September 2024

Twelve compounds, including four undescribed cytochalasins, xylariachalasins A–D (1–4), four undescribed polyketides (5–8), and four known cytochalasins (9–12), were isolated from the mangrove endophytic fungus Xylaria arbuscula QYF. Their structures and absolute configurations were established by extensive spectroscopic analyses (1D and 2D NMR, HRESIMS), electronic circular dichroism (ECD) calculations, 13C NMR calculation and DP4+ analysis, single-crystal X-ray diffraction, and the modified Mosher ester method. Compounds 1 and 2 are rare cytochalasin hydroperoxides. In bioactivity assays, Compound 2 exhibited moderate antimicrobial activities against Staphylococcus aureus and Candida albicans with MIC values of 12.5 μM for both Compound 10 exhibited significant cytotoxic activity against MDA-MB-435 with an IC50 value of 3.61 ± 1.60 μM.
Research on Reverse Osmosis (RO)/Nanofiltration (NF) Membranes Based on Thin Film Composite (TFC) Structures: Mechanism, Recent Progress and Application
Authors: Geng Huibin , Zhang Weihao , Zhao Xiaoxu , Shao Wei , Wang Haitao
Published: September 2024

The global shortage of clean water is a major problem, even in water-rich regions. To solve this problem, low-cost and energy-efficient water treatment methods are needed. Membrane separation technology (MST), as a separation method with low energy consumption, low cost, and good separation effect, has been widely used to deal with seawater desalination, resource recovery, industrial wastewater treatment, and other fields. With the continuous progress of scientific and technological innovation and the increasing demand for use, NF/RO membranes based on the TFC structure are constantly being upgraded. This paper presents the recent research progress of NF and RO membranes based on TFC structures and their applications in different fields, especially the formation mechanism and regulation of selective layer structures and the modification methods of selective layers. Our summary provides fundamental insights into the understanding of NF and RO membrane processes and hopefully triggers further thinking on the development of membrane filtration process optimization.
Effect of Zn Addition on the Microstructure and Discharge Performance of Mg-Al-Mn-Ca Alloys for Magnesium-Air Batteries
Authors: Gong Yiwei , Wei Kezheng , Jiang Wenlong , Xiang Chongchen , Ding Hanlin , Wang Zijian
Published: September 2024

This study explores the effects of Zn addition through micro-alloying on the microstructure and discharge performance of Mg-Al-Mn-Ca alloy anodes for magnesium-air batteries. The results show that the second-phase particles (d > 1 μm) in a Mg-Al-Mn-Ca alloy promote dynamic recrystallization (DRX) via particle-stimulated nucleation (PSN), resulting in a uniform equiaxed grain structure and fiber texture. In contrast, Zn and Ca co-segregation in a Mg-Al-Mn-Ca-Zn alloy facilitates continuous dynamic recrystallization (CDRX) and, combined with the PSN mechanism, forms a unique structure where three types of grains with different grain boundary densities coexist. The addition of Zn and Ca effectively reduces the c/a axis ratio, promoting texture homogenization. The Mg-Al-Mn-Ca alloy exhibits rough discharge surfaces due to simultaneous discharge at numerous grain boundaries and severe hydrogen evolution corrosion from micro-galvanic effects, inducing the chunk effect (CE). Conversely, the structure where three types of grains with different grain boundary densities coexist in the Mg-Al-Mn-Ca-Zn alloy promotes discharge product detachment through stress cracking, achieving uniform discharge and significantly enhancing discharge performance. The uniform texture reduces hydrogen evolution corrosion, improving anode utilization. This study demonstrates that controlling the microstructure, particularly grain boundary density and grain texture, enables the development of high-performance Mg-Al-Mn-Ca-Zn alloy anodes, especially at higher current densities, offering a new strategy for designing efficient magnesium alloy anode materials.
Microeukaryotes Associated with Freshwater Mussels in Rivers of the Southeastern United States
Authors: Halliday-Isaac Akacia K. , Jackson Colin R.
Published: September 2024

Microeukaryotes are a diverse and often overlooked group of microbes that are important in food webs and other ecological linkages. Little is known about microeukaryotes associated with aquatic invertebrates, although filter feeders such as mussels are likely to take in and potentially retain microeukaryotes in their gut while feeding. Microeukaryotes such as apicomplexans have been reported in marine mussel species, but no studies have examined the presence of these microorganisms in freshwater mussels or how they relate to mussel host species or environmental conditions. In this study, microbial community DNA was extracted from the gut tissue of over 300 freshwater mussels, representing 22 species collected from rivers in the southeastern USA. Microeukaryote DNA was detected using PCR amplification, followed by the sequencing of positive amplicons. Microeukaryotes were found in 167 individual mussels (53%) of those tested. Amplicons included dinoflagellates/algae that differed between mussel species and are likely food sources that were distinct from those found in water and sediment samples analyzed concurrently. A total of 5% of the positive amplicons were non-photosynthetic alveolates that could represent parasitic microeukaryotes. Understanding the distribution of microeukaryotes in the freshwater mussel gut microbiome could further our understanding of the ongoing decline of mussel populations.
Calorie Restriction Decreases Competitive Fitness in Saccharomyces cerevisiae Following Heat Stress
Authors: Hill Lucy , Guyot Stéphane , Bertheau Lucie , Davey Hazel
Published: September 2024

Experiments exposing Saccharomyces cerevisiae to glucose limitation (calorie restriction) are widely used to determine impacts on cell health as a model for aging. Using growth on plates and in liquid culture, we demonstrated that calorie restriction reduces fitness in subsequent nutrient-limited environments. Yeast grown in a calorie-restricted environment took longer to emerge from the lag phase, had an extended doubling time and had a lower percentage of culturability. Cells grown under moderate calorie restriction were able to withstand a gradual heat stress in a similar manner to cells grown without calorie restriction but fared less well with a sudden heat shock. Yeast grown under extreme calorie restriction were less fit when exposed to gradual heating or heat shock. Using RNAseq analysis, we provide novel insight into the mechanisms underlying this response, showing that in the absence of calorie restriction, genes whose products are involved in energy metabolism (glycolysis/gluconeogenesis and the citrate cycle) are predominantly overexpressed when yeasts were exposed to gradual heating, whereas this was not the case when they were exposed to shock. We show that both the culture history and the current environment must be considered when assaying physiological responses, and this has wider implications when developing strategies for the propagation, preservation or destruction of microbial cells.
Identification and Characterization of Human Breast Milk and Infant Fecal Cultivable Lactobacilli Isolated in Bulgaria: A Pilot Study
Authors: Asenova Asya , Hristova Hristiyana , Ivanova Stanimira , Miteva Viliana , Zhivkova Ivelina , Stefanova Katerina , Moncheva Penka , Nedeva Trayana , Urshev Zoltan , Marinova-Yordanova Victoria , Georgieva Tzveta , Tzenova Margarita , Russinova Maria , Borisova Tzvetomira , Donchev Deyan , Hristova Petya , Rasheva Iliyana
Published: September 2024

During the last few decades, the main focus of numerous studies has been on the human breast milk microbiota and its influence on the infant intestinal microbiota and overall health. The presence of lactic acid bacteria in breast milk affects both the quantitative and qualitative composition of the infant gut microbiota. The aim of this study was to assess the most frequently detected cultivable rod-shaped lactobacilli, specific for breast milk of healthy Bulgarian women and fecal samples of their infants over the first month of life, in 14 mother–infant tandem pairs. Additionally, we evaluated the strain diversity among the most common isolated species. A total of 68 Gram-positive and catalase-negative strains were subjected to identification using the MALDI-TOF technique. Predominant cultivable populations belonging to the rod-shaped lactic acid bacteria have been identified as Lacticaseibacillus rhamnosus, Limosilactobacillus fermentum, Lacticaseibacillus paracasei, and Limosilactobacillus reuteri. Also, we confirmed the presence of Lactiplantibacillus plantarum and Lactobacillus gasseri. Up to 26 isolates were selected as representatives and analyzed by 16S rRNA sequencing for strain identity confirmation and a phylogenetic tree based on 16S rRNA gene sequence was constructed. Comparative analysis by four RAPD primers revealed genetic differences between newly isolated predominant L. rhamnosus strains. This pilot study provides data for the current first report concerning the investigation of the characteristic cultivable lactobacilli isolated from human breast milk and infant feces in Bulgaria.
Treatment of Anaerobic Digester Liquids via Membrane Biofilm Reactors: Simultaneous Aerobic Methanotrophy and Nitrogen Removal
Authors: Tentori Egidio F. , Wang Nan , Devin Caroline J. , Richardson Ruth E.
Published: September 2024

Anaerobic digestion (AD) produces useful biogas and waste streams with high levels of dissolved methane (CH4) and ammonium (NH4+), among other nutrients. Membrane biofilm reactors (MBfRs), which support dissolved methane oxidation in the same reactor as simultaneous nitrification and denitrification (ME-SND), are a potential bubble-less treatment method. Here, we demonstrate ME-SND taking place in single-stage, AD digestate liquid-fed MBfRs, where oxygen (O2) and supplemental CH4 were delivered via pressurized membranes. The effects of two O2 pressures, leading to different O2 fluxes, on CH4 and N removal were examined. MBfRs achieved up to 98% and 67% CH4 and N removal efficiencies, respectively. The maximum N removal rates ranged from 57 to 94 mg N L−1 d−1, with higher overall rates observed in reactors with lower O2 pressures. The higher-O2-flux condition showed NO2− as a partial nitrification endpoint, with a lower total N removal rate due to low N2 gas production compared to lower-O2-pressure reactors, which favored complete nitrification and denitrification. Membrane biofilm 16S rRNA amplicon sequencing showed an abundance of aerobic methanotrophs (especially Methylobacter, Methylomonas, and Methylotenera) and enrichment of nitrifiers (especially Nitrosomonas and Nitrospira) and anammox bacteria (especially Ca. Annamoxoglobus and Ca. Brocadia) in high-O2 and low-O2 reactors, respectively. Supplementation of the influent with nitrite supported evidence that anammox bacteria in the low-O2 condition were nitrite-limited. This work highlights coupling of aerobic methanotrophy and nitrogen removal in AD digestate-fed reactors, demonstrating the potential application of ME-SND in MBfRs for the treatment of AD’s residual liquids and wastewater. Sensor-based tuning of membrane O2 pressure holds promise for the optimization of bubble-less treatment of excess CH4 and NH4+ in wastewater.