bluuebunny/crossref_metadata_2025 huggingface dataset:
Skid Resistance of Asphalt Pavements
Authors: Rosta Szabolcs , Gáspár László
Published: June 2023

Skid resistance of a road pavement surface is the force developed when a tyre is prevented from rotating and slides along the pavement surface. This property comes from the combination of the macro- and micro-texture of pavement. The skid resistance of an asphalt pavement is an important parameter influencing driving safety on a road since there is a proven relationship between skid resistance and accident parameters. This paper deals with the measurement principle of pavement skid resistance (surface friction) including longitudinal and transverse friction. A high number of measuring devices of skid resistance are also introduced, highlighting their advantages and limitations. Moreover, the measurement policies in the European Union and in Hungary are outlined. Pavement surface texture is investigated, dealing with the levels of surface texture, the most common measuring techniques, the macro-texture features of asphalt types, as well as the Hungarian regulation in the field. As a related topic, the aggregate properties and their implication in the relevant Hungarian specification are introduced briefly as well. Some outcomes of the EU’s COST Action 354 on the development of unified European macro-roughness and skid resistance performance indicators and indices are also presented.
A Deep Learning-Based Visual Map Generation for Mobile Robot Navigation
Authors: García-Pintos Carlos A. , Aldana-Murillo Noé G. , Ovalle-Magallanes Emmanuel , Martínez Edgar
Published: June 2023

Visual map-based robot navigation is a strategy that only uses the robot vision system, involving four fundamental stages: learning or mapping, localization, planning, and navigation. Therefore, it is paramount to model the environment optimally to perform the aforementioned stages. In this paper, we propose a novel framework to generate a visual map for environments both indoors and outdoors. The visual map comprises key images sharing visual information between consecutive key images. This learning stage employs a pre-trained local feature transformer (LoFTR) constrained with a 3D projective transformation (a fundamental matrix) between two consecutive key images. Outliers are efficiently detected using marginalizing sample consensus (MAGSAC) while estimating the fundamental matrix. We conducted extensive experiments to validate our approach in six different datasets and compare its performance against hand-crafted methods.
Comparison of Raspberry Ketone Production via Submerged Fermentation in Different Bioreactors
Authors: Zhang Yi , Peterson Eric Charles , Ng Yuen Ling , Goh Kheng-Lim , Zivkovic Vladimir , Chow Yvonne
Published: June 2023

Raspberry ketone (RK) has high commercial value in the food and healthcare industries. A biological route to this flavour compound is an attractive prospect, considering the need to meet consumer demands and sustainable goals; however, it is yet to become an industrial reality. In this work, fungal production of raspberry ketone (RK) and raspberry compounds (RC) via submerged fermentation of Nidula niveo-tomentosa was characterized in flask, stirred-tank reactor (STR), panel bioreactor (PBR), and fluidized bed reactor (FBR) configurations. The results indicate that the panel bioreactor resulted in larger, floccose pellets accompanied by maximum titres of 20.6 mg/L RK and 50.9 mg/L RC. The stirred-tank bioreactor with impeller mixing yielded compact elliptical pellets, induced the highest volumetric productivity of 2.0 mg L−1 day−1, and showed RK selectivity of 0.45. While differing mixing strategies had clear effects on pellet morphology, RK production presented a more direct positive relationship with cultivation conditions, and showed appropriate mixing and aeration favour RK to raspberry alcohol (RA). Overall, this paper highlights the importance of bioreactor design to fungal fermentation, and gives insight into green and industrial bioproduction of value-added natural compounds.
Quality Improvement of Zao Pepper by Inoculation with Lactobacillus plantarum 5-1: Probiotic Ability and Fermentation Characteristics of Lactic Acid Bacteria
Authors: Cai Yafei , Wu Yongjun , Li Cen , Zhang Lincheng , Tong Shuoqiu , Yuan Shenglan
Published: June 2023

Zao pepper is a fermented type with a distinct flavor, and Zao pepper-based dishes are popular. However, in spontaneous fermentation (SF), the adverse microorganisms of Zao pepper are uncontrollable and alter the product quality. Lactic acid bacteria (LAB) inhibit the growth of harmful bacteria and endow a sour taste in SF. Therefore, the purpose of this study was to isolate autochthonic LAB from SF and through inoculated fermentation (IF) to improve Zao pepper quality. Four LAB strains were selected for probiotic experiments by sensory evaluation based on the flavor of Zao pepper in vitro. Intriguingly, Lactobacillus plantarum 5-1 showed superior safety and probiotics, with the fastest growth and acid-production rate. Moreover, the nitrite reductase viability of L. plantarum 5-1 reached 4.73 μmol/mL·h. The use of IF via L. plantarum 5-1 increased the total acid content 2-fold and reduced the nitrite content by 0.36-fold compared to SF in Zao pepper. In addition, IF improved the color and texture of Zao pepper. These results indicate that the autochthonic L. plantarum 5-1 improved the quality of Zao pepper, providing a new strategy for enhancing the stability of fermented pepper.
A Comparison of Analytical Methods for the Determination of Soil pH: Case Study on Burned Soils in Northern Portugal
Authors: Faria Maria , Bertocco Tamires , Barroso Ana , Carvalho Manuela , Fonseca Felicia , Delerue Matos Cristina , Figueiredo Tomás , Sequeira Braga Amália , Valente Teresa , Jiménez-Ballesta Raimundo
Published: June 2023

Wildfires can cause serious imbalances in ecosystems, primarily at the soil level, making it vulnerable to degradation processes such as erosion. During and after a fire, changes occur in soil properties, including pH, which affects the solubility and availability of nutrients. Currently, there is a great diversity of protocols, some involving normalized standards, to determine soil pH, but there is no consensual or universal analytical method for this parameter, especially in burned soils, in which mineral and organic fractions could have been modified. Therefore, the objective of the present work is to evaluate the effect that variations in these analytical protocols may have on pH results. For this, five methods commonly found in the international bibliography for the analysis of pH of soil in water (pHH2O) were selected and compared to propose the most precise procedure. The analytical methods were applied to 43 soil samples, collected in a plot subjected to prescribed burning in the Parque Natural de Montesinho (Northern Portugal). The studied methods differ in the following protocol items: water suspension ratio (1:2.5 or 1:5), mechanical stirring time in the suspension (10 min or 1 h), and in the resting time for the solid particles to settle (15 min or 8 h). The obtained results point to the suitability of the five methods used for soil pH analysis, indicating that there are no statistically significant differences. However, results also allow suggesting a more appropriate method concerning practical reasons, such as labor in a lab. Thus, to make the analysis process more profitable, M2 is a good option because it uses a small amount of sample (5 g), short agitation (10 min) and settling time (15 min). In turn, M1 and M5, which use a lower proportion of soil (1:2.5) show lower pH variation in the measurements. This fact may be explained by a smaller dilution effect. Considering that these two methods differ in the settling time, it is suggested to apply M1, because only 15 min are required. Therefore, the main conclusion reached with this work is that the measurement of soil pH using M1, i.e., a soil:water ratio of 1:2.5, with agitation of 10 min and settling time of 15 min, is a robust and more expeditious protocol to be applied to soil samples after a fire.
Cultural Industry’s Strategic Development: Reaching International Audience by Using Virtual Reality and Augmented Reality Technologies
Authors: Kargas Antonios , Loumos Georgios
Published: June 2023

In the last ten years, Virtual Reality (VR) and Augmented Reality (AR) technologies have been rapidly developed as a means to distribute digital content and to disseminate organizations worldwide. Cultural industry adopted these technologies and developed applications as a means of strategic development in the digital world and in order to “internationalize” their audience. Moreover, these technologies offered the opportunity to reshape the whole industry by enriching (physical and digital) visitors’ experiences. Current research provides evidence about developing VR and AR tools that can act as internationalization facilitators when it comes to cultural industry. Research was conducted during the “VARSOCUL” project funded by the European Regional Development Fund (ERDF) as part of the Greek National Scope Action entitled “RESEARCH-CREATE-INNOVATE”. The project’s main result are presented, alongside with VR and AR tools developed.
Metal Artefacts and Remains of Armour from Kozlov Rob Castle: Metallurgical Analyses as a Tool for Identification and Interpretation of Fragmentary Archaeological Finds
Authors: Kraner Jakob , Lazar Tomaž , Mlinar Miha , Burja Jaka
Published: June 2023

The castle on Kozlov Rob above Tolmin is one of the most important historical sites in western Slovenia. Over the years, large quantities of finds dating from the late medieval and early modern periods have been recovered from the castle ruins in the process of archaeological investigations and construction works. Many of the recovered iron artefacts are extremely difficult to identify due to their fragmentary state. This paper presents the study of four relatively recently discovered artefacts. The available evidence suggests that at least one of them belongs to a helmet, while another has been identified as the remains of a lock. The artefacts were analysed with X-ray radiography and X-ray diffraction. Additionally, samples were taken for microhardness Vickers measurements and metallographic analysis with a light microscope and a scanning electron microscope. Additional microchemical and structural phase analysis were done with the electron microscope. The aim of archaeometallurgical analyses is to contribute to a more precise interpretation and add a new dimension to our knowledge of the castle site at Kozlov Rob.
New Insight on Medieval Painting in Sicily: The Virgin Hodegetria Panel in Monreale Cathedral (Palermo, Italy)
Authors: Amadori Maria Letizia , Mengacci Valeria , Sebastianelli Mauro , Pignataro Bruno , Agnello Simonpietro , Triolo Paolo , Pellerito Claudia
Published: June 2023

The Virgin Hodegetria, located in the Cathedral of Santa Maria Nuova in Monreale, near Palermo (Italy), probably dating the first half of the 13th century, is one of the earliest examples of medieval panel painting in Sicily. A diagnostic campaign was carried out on the panel aiming to identify the constituting materials and the executive technique, as well as to assess the state of conservation for supporting the methodological choice of the restoration intervention. Both non-invasive (X-ray radiography, digital microscope, multispectral imaging, ED-X-ray fluorescence) and micro-invasive (polarised light microscopy, ESEM-EDX, ATR-FTIR spectroscopy and micro-Raman spectroscopy) analyses were performed. According to the results, the executive technique followed the 13th–14th-century Italian painting tradition. A complex structure was applied on the wooden support, consisting of a double layer of canvas and several ground layers of gypsum and glue-based binder. The underdrawing was made by a brush using carbonaceous black pigment. The original palette includes red ochre, red lead, azurite, carbon black and bone black. During the several restorations, mercury-based red, indigo, smalt blue, orpiment and synthetic mars were used. The original silver leaf of the frame was covered with red tin-based lake and subsequently regilded with gold leaf. Proteinaceous and oil binders were also detected.
Harnessing Epigenetics through Grafting: Revolutionizing Horticultural Crop Production
Authors: Jin Qiang , Chachar Muzafaruddin , Ahmed Nazir , Zhang Pingxian , Chachar Zaid , Geng Yuke , Guo Dayong , Chachar Sadaruddin
Published: June 2023

Grafting is an ancient agricultural technique that is frequently used to enhance the performance of horticultural plants, including vegetables and woody fruit trees. For successful grafting, genotypes of the compatible scion (the upper part) and the rootstock (the lower part) must interact. Molecular signals, including nutritional and hormonal signals, proteins, and messenger RNAs (mRNAs), are known to be transferred from the rootstock to the scion and vice versa. Nonetheless, there are still numerous mysteries regarding artificial grafts, including the occurrence of genetic/epigenetic alterations due to exchanges between the graft partners, and the long-term ramifications of these alterations on the phenotype are unknown. Recent studies on the interactions between rootstocks and scions suggest that grafting responses have an epigenetic component. In this review, we focus on the current knowledge of epigenetic consequences following grafting. Epigenetic regulations are known to regulate chromatin architecture, alter gene expression, and affect cellular function in plants. Mobile small RNAs, for example, have been shown to modify the DNA methylation pattern of the recipient partner across the graft union. More recently, mRNA 5-methylcytosine (m5C) modification has been shown to elucidate the long-distance transport mechanism of grafting in Arabidopsis thaliana. We also discuss how grafts can cause heritable epigenetic alterations that result in novel plant phenotypes, and how this might help increase horticultural crop quality, yield, and stress resistance in the context of climate change.
In Vitro Growth and Regeneration of Brassica oleracea var. gongylodes: A Decade of Research
Authors: Ćosić Tatjana , Raspor Martin , Motyka Václav , Cingel Aleksandar , Ninković Slavica
Published: June 2023

Kohlrabi (Brassica oleracea var. gongylodes) is a vegetable cultivated for its edible stem tuber. Although valued for its nutritional properties and tolerance to abiotic stress, kohlrabi is one of the least studied brassicas. In this review, we summarize the results of our decade-long research on in vitro morphogenesis of kohlrabi, starting from 2013. Protocols for efficient in vitro regeneration with minimal requirements for external application of plant growth regulators (PGRs) have been developed, both by somatic embryogenesis (SE) and by de novo shoot organogenesis (DNSO). Efficient regeneration by direct SE was achieved using immature zygotic embryos as explants incubated on PGR-free media, and the production process was maintained in culture thanks to highly efficient secondary SE. Conversely, efficient regeneration by indirect DNSO was achieved using entire seedlings as explants and adding only cytokinin (CK) without the need for exogenous auxin. Comprehensive phytohormone analyses revealed that different exogenously applied CKs differentially affected the composition of endogenous phytohormones and induced changes in the expression of cell cycle-related genes and other genes involved in the organogenic response. The addition of high sucrose concentrations to the nutrient media failed to induce the formation of stem tubers in in vitro culture, but revealed a complex interaction with exogenously applied CKs, interfering with both the endogenous phytohormonome and the expression of organogenesis-related genes. Our work has provided substantial biotechnological advances in the field of in vitro regeneration of kohlrabi, as well as in understanding the underlying phytohormonal regulation. The review aims to introduce kohlrabi to the scientific community as a model system for both basic and applied research, while we continue seeking answers to the outstanding questions and trying to pave the way for the development of more resistant varieties.
M-Ary Direct Modulation Chirp Spread Spectrum for Spectrally Efficient Communications
Authors: Zacko Gbadoubissa Jocelyn Edinio , Abba Ari Ado Adamou , Radoi Emanuel , Gueroui Abdelhak Mourad
Published: June 2023

Spread spectrum techniques, such as the Chirp Spread Spectrum (CSS) used by LoRa technology, are important for machine-to-machine communication in the context of the Internet of Things. They offer high processing gain, reliable communication over long ranges, robustness to interference and noise in harsh environments, etc. However, these features are compromised by their poor spectral efficiency, resulting in a very low data transmission rate. This paper deals with a spectrally efficient variant of CSS. The system uses M-ary phase keying to modulate the data and exploits CSS’s properties to transmit the modulated symbols as overlapping chirps. The overlapping of chirp signals may affect the system performance due to inter-symbol interference. Therefore, we analyse the relationship between the number of overlaps and the effect of inter-symbol interference (ISI), and we also determine the BER expression as a function of the number of overlaps. Finally, we derive the optimal number of overlapping symbols that corresponds to the minimum error probability.
Chemical Bonding in the C2 Molecule
Authors: Sax Alexander F.
Published: June 2023

Bonding in the C2 molecule is investigated with CAS(8,8) wave functions using canonical MOs. In a subsequent step, orthogonal atomic orbitals are constructed by localizing the CASSCF MOs on the two carbon atoms with an orthogonal transformation. This orbital transformation causes an orthogonal transformation of the configuration state functions (CSF) spanning the function space of the singlet ground state of C2. Instead of CSFs built from canonical MOs, one obtains CSFs of orthogonal deformed atomic orbitals (AO). This approach resembles the orthogonal valence bond (OVB) methods’ CSFs, which are very different from the conventional VB, based on non-orthogonal AOs. To become used to the different argumentation, the bonding situations in ethane (single bond), ethene (double bond), and the nitrogen molecule (triple bond) are also studied. The complex bonding situation in C2 is caused by the possibility to excite an electron with a spin flip from the doubly occupied 2s AO into the 2p subshell, and the resulting high-spin 5Su state of the carbon atom allows for a better reduction of the Pauli repulsion. However, the electron structure around the equilibrium distance does not allow one to say that C2 in its ground state has a double, or triple, or even a quadruple bond.
Mechanical and Viscoelastic Properties of Carbon Fibre Epoxy Composites with Interleaved Graphite Nanoplatelet Layer
Authors: Palmieri Barbara , Siviello Ciro , Petriccione Angelo , Espresso Manuela , Giordano Michele , Martone Alfonso , Cilento Fabrizia
Published: June 2023

The use of interleaving material with viscoelastic properties is one of the most effective solutions to improve the damping capacity of carbon fibre-reinforced polymer (CFRP) laminates. Improving composite damping without threatening mechanical performance is challenging and the use of nanomaterials should lead to the target. In this paper, the effect of a nanostructured interlayer based on graphite nanoplatelets (GNPs) on the damping capacity and fracture toughness of CFRP laminates has been investigated. High-content GNP/epoxy (70 wt/30 wt) coating was sprayed on the surface of CF/epoxy prepregs at two different contents (10 and 40 g/m2) and incorporated at the middle plane of a CFRP laminate. The effect of the GNP areal weights on the viscoelastic and mechanical behaviour of the laminates is investigated. Coupons with low GNP content showed a 25% increase in damping capacity with a trivial reduction in the storage modulus. Moreover, a reduction in interlaminar shear strength (ILSS) and fracture toughness (both mode I and mode II) was observed. The GNP alignment and degree of compaction reached during the process were found to be key parameters on material performances. By increasing the GNP content and compaction, a mitigation on the fracture drop was achieved (−15%).
Ready-to-Use Recycled Carbon Fibres Decorated with Magnetic Nanoparticles: Functionalization after Recycling Process Using Supercritical Fluid Chemistry
Authors: Martin Sophie , Milickovic Tatjana Kosanovic , Charitidis Costas A. , Moisan Sandy
Published: June 2023

An innovative simultaneous process, using supercritical fluid (SCF) chemistry, was used to recycle uncured prepregs and to functionalize the recovered carbon fibres with Fe3O4 magnetic nanoparticles (MNPs), to produce a new type of secondary raw material suitable for composite applications. This specific functionalization allows the fibres to be heated by induction through a hysteresis loss mechanism characteristic for nanoparticle susceptor-embedded systems, for triggered healing properties and a potentially easy route for CF reclamation. Using SCF and hydrothermal conditions for recycling, functionalization of fibres can be performed in the same reactor, resulting in the creation of ready-to-use fibres and limiting the use organic solvent. After cutting the uncured prepreg to the desired length to fit in future applications, supercritical CO2 extraction is performed to partially remove some components of the uncured prepreg matrix (step 1). Then, the recycled carbon fibres (rCFs), still embedded inside the remaining organic matrix, are brought into contact with reactants for the functionalization step (step 2). Two possibilities were studied: the direct synthesis of MNPs coated with PAA in hydrothermal conditions, and the deposition of already synthesized MNPs assisted by supercritical CO2-acetone. No CF surface activation is needed thanks to the presence of functional groups due to the remaining matrix. After functionalization, ready-to-use material with homogeneous depositions of MNPs at the surface of rCF is produced, with a strong magnetic behaviour and without observed degradation of the fibres.
Countermovement Jump Performance Is Related to Ankle Flexibility and Knee Extensors Torque in Female Adolescent Volleyball Athletes
Authors: Panoutsakopoulos Vassilios , Bassa Eleni
Published: June 2023

Ankle flexibility and isokinetic knee torque/power generating capacity were previously suggested to contribute or to be correlated to the vertical countermovement jump (CMJ) performance. The aim of this study was to investigate the effect of the passive ankle joint dorsi flexion (θPDF) and the knee muscle’s isokinetic torque and power on the CMJ in adolescent female volleyball players. The θPDF at a knee extension angle of 140 degrees were measured for 37 female post-pubertal volleyball players. Then, the players were assigned to either the flexible (n = 10) or inflexible (n = 14) groups according to earlier recommended criteria. Testing included the CMJ with and without an arm swing, and maximal knee extensions and flexions in 3 angular velocities on an isokinetic dynamometer. CMJ height performed with or without an arm swing (r(22) = 0.563, p = 0.040 and r(22) = 0.518, p = 0.009, respectively) and relative power (r(22) = 0.517, p = 0.010 and r(22) = 0.446, p = 0.030, respectively) were positively correlated with the extensors’ torque at 180°/s and were negatively correlated with the flexibility level of the dominant side ankle (r(22) = −0.529, p = 0.008 and r(22) = −0.576, p = 0.030, respectively). A moderate positive correlation was also revealed between the CMJ height with and without an arm swing and the power of the non-dominant knee extensors (r(22) = 0.458, p = 0.024 and r(22) = 0.402, p = 0.049, respectively) and flexors (r(22) = 0.484, p = 0.016 and r(22) = 0.477, p = 0.018, respectively). Results of the 2 × 2 repeated ANOVA measurements revealed that flexible players jumped significantly (p < 0.05) higher during the CMJs, whilst there was a group effect only on the isokinetic knee extensor muscles’ torque. In conclusion, a more flexible ankle joint and a higher isokinetic knee extensor’s torque generating capacity resulted in higher CMJ performance. Therefore, ankle flexibility should be emphasized in training and is suggested to be included in preseason screening tests of youth female volleyball players.
Novel Antifungals and Aspergillus Section Terrei with Potpourri Susceptibility Profiles to Conventional Antifungals
Authors: Vahedi-Shahandashti Roya , Houbraken Jos , Birch Mike , Lass-Flörl Cornelia
Published: June 2023

The epidemiology of invasive fungal infections (IFIs) is currently changing, driven by aggressive immunosuppressive therapy, leading to an expanded spectrum of patients at risk of IFIs. Aspergillosis is a leading cause of IFIs, which usually affects immunocompromised patients. There are a limited number of antifungal medications available for treating IFIs, and their effectiveness is often hindered by rising resistance rates and practical limitations. Consequently, new antifungals, especially those with novel mechanisms of action, are increasingly required. This study assessed the activity of four novel antifungal agents with different mechanisms of activity, namely, manogepix, rezafungin, ibrexafungerp, and olorofim, against 100 isolates of Aspergillus section Terrei, containing amphotericin-B (AmB)-wildtype/non-wildtype and azole-susceptible/-resistant strains, according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) method. In general, all tested agents showed potent and consistent activity against the tested isolates, exhibiting geometric mean (GM) and minimum effective concentration (MEC)/minimum inhibitory concentration (MIC) ranges, respectively, as follows: manogepix (0.048 mg/L, 0.032–0.5 mg/L), rezafungin (0.020 mg/L, 0.016–0.5 mg/L), ibrexafungerp (0.071 mg/L, 0.032–2 mg/L), and olorofim (0.008 mg/L, 0.008–0.032 mg/L). In terms of MIC90/MEC90, olorofim had the lowest values (0.008 mg/L), followed by rezafungin (0.032 mg/L), manogepix (0.125 mg/L), and ibrexafungerp (0.25 mg/L). All the antifungals tested demonstrated promising in vitro activity against Aspergillus section Terrei, including A. terreus as well as azole-resistant and AmB-non-wildtype cryptic species.
FDG PET/CT as a Tool for Early Detection of Bleomycin-Induced Pulmonary Toxicity
Authors: Shaikh Hira , Omer Zulfa , Jandarov Roman A. , McBee Morgan P. , Scheler Jennifer , Mahoney Bruce , Latif Tahir
Published: June 2023

Bleomycin-induced pulmonary toxicity (BPT) is a serious and potentially fatal complication of bleomycin, a key component of Hodgkin lymphoma (HL) treatment. Before ours, only one published study evaluated the predictability of 18F-FDG-PET/CT for the early diagnosis of BPT. In this retrospective cohort study, 18F-FDG-PET/CT scans of adult HL patients treated with bleomycin at an urban academic center over five years were assessed by radiologists blinded to the clinical information, and scans were correlated with clinical BPT. We found 11 HL patients with 54 interim or end-of-treatment 18F-FDG-PET/CT scans who had received bleomycin. Five of the eleven (5/11, 45%) patients had radiographic changes in PET/CT and developed clinical BPT. Patients with clinical BPT had higher FDG uptake in lungs compared to those who did not (SUVmax mean 2.66 (CI 1.8–3.7) vs. 0.86 (CI 0.4–1.9), Mann–Whitney U test, p < 0.05). In a separate cohort analysis, we compared HL patients with clinical BPT (9/25, 36%) and without clinical BPT (16/25, 64%) to assess potential risk factors. Low hemoglobin (p = 0.037) and high ESR values (p = 0.0289) were associated with clinical BPT. Furthermore, gender, stage, histology, prior lung radiation, G-CSF, or steroids did not significantly confer a higher risk of BPT. 18F-FDG-PET/CT imaging, which is routinely used to assess treatment response in HL, is useful for early detection of BPT, which can have high mortality and morbidity.
[4,6-Di-tert-butyl-N-(2,6-Dimethylphenyl)-o-Amidophenolato][4,6-Di-tert-butyl-N-(2,6-Dimethylphenyl)-o-Iminobenzosemiquinolato](2,2′-Bipyridyl)Indium(III)
Authors: Ershova Irina V. , Cherkasov Anton V. , Piskunov Alexandr V.
Published: June 2023

A six-coordinated indium(III) complex (APMe)(imSQMe)In(bipy) (1), bearing two types of redox-active ligands—mono- (imSQMe) and dianion (APMe) of 4,6-di-tert-butyl-N-(2,6-dimethylphenyl)-o-iminobenzoquinone and 2,2′-bipyridyl—was synthesized and characterized in detail. The intense, well-resolved ESR spectrum of 1 in dichloromethane solution clearly indicates the spin density delocalization between both AP and imSQ ligands. The UV-vis spectrum of 1 possesses an absorption band in the NIR region. The molecular structure of compound 1 was established by single-crystal X-ray diffraction analysis.
Systematic Review of Recommendation Systems for Course Selection
Authors: Algarni Shrooq , Sheldon Frederick
Published: June 2023

Course recommender systems play an increasingly pivotal role in the educational landscape, driving personalization and informed decision-making for students. However, these systems face significant challenges, including managing a large and dynamic decision space and addressing the cold start problem for new students. This article endeavors to provide a comprehensive review and background to fully understand recent research on course recommender systems and their impact on learning. We present a detailed summary of empirical data supporting the use of these systems in educational strategic planning. We examined case studies conducted over the previous six years (2017–2022), with a focus on 35 key studies selected from 1938 academic papers found using the CADIMA tool. This systematic literature review (SLR) assesses various recommender system methodologies used to suggest course selection tracks, aiming to determine the most effective evidence-based approach.
A Mathematical Framework for Enriching Human–Machine Interactions
Authors: Ehresmann Andrée C. , Béjean Mathias , Vanbremeersch Jean-Paul
Published: June 2023

This paper presents a conceptual mathematical framework for developing rich human–machine interactions in order to improve decision-making in a social organisation, S. The idea is to model how S can create a “multi-level artificial cognitive system”, called a data analyser (DA), to collaborate with humans in collecting and learning how to analyse data, to anticipate situations, and to develop new responses, thus improving decision-making. In this model, the DA is “processed” to not only gather data and extend existing knowledge, but also to learn how to act autonomously with its own specific procedures or even to create new ones. An application is given in cases where such rich human–machine interactions are expected to allow the DA+S partnership to acquire deep anticipation capabilities for possible future changes, e.g., to prevent risks or seize opportunities. The way the social organization S operates over time, including the construction of DA, is described using the conceptual framework comprising “memory evolutive systems” (MES), a mathematical theoretical approach introduced by Ehresmann and Vanbremeersch for evolutionary multi-scale, multi-agent and multi-temporality systems. This leads to the definition of a “data analyser–MES”.
Ovarian Leydig Cell Tumor and Ovarian Hyperthecosis in a Postmenopausal Woman: A Case Report and Literature Review
Authors: Bužinskienė Diana , Marčiukaitytė Rūta , Šidlovska Evelina , Rudaitis Vilius
Published: June 2023

Ovarian Leydig cell tumor is a rare type of ovarian steroid cell neoplasms, presenting in only 0.1% of all ovarian tumor cases, and is generally androgen-secreting and unilateral. Although they are often malignant non-spreading tumors, which have excellent prognosis, benign ovarian Leydig cell tumors with low-risk malignancy can be also detected. Ovarian hyperthecosis is a rare non-neoplastic disorder, in most cases bilateral. Ovarian tumors and ovarian hyperthecosis are one of the main causes of hyperandrogenism in postmenopausal women, a condition strongly associated with both hormonal and metabolic changes. Here, we report a 65-year-old patient with complaints of excessive body hairiness and alopecia. The laboratory investigation showed increased levels of serum testosterone and dehydroepiandrosterone sulfate (DHEA-S). Imaging, including transvaginal ultrasound and pelvic MRI revealed the presence of two masses in the ovaries. The patient underwent a laparoscopic bilateral salpingo-oophorectomy due to the ovarian tumors unknown etiology, and histopathological examination revealed a unilateral benign left ovarian Leydig cell tumor with bilateral ovarian stromal hyperplasia and ovarian hyperthecosis. Making differential diagnosis between ovarian tumors and ovarian hyperthecosis is difficult. Bilateral salpingo-oophorectomy is the treatment of choice in postmenopausal women with benign Leydig cell ovarian tumor, as well as ovarian hyperthecosis, as it offers both a cure and diagnostic confirmation.
The Effect of Divinylbenzene on the Structure and Properties of Polyethylene Films with Related Radiation Chemical Grafted Polystyrene and Sulfocationite Membranes
Authors: Chalykh Anatoly , Khasbiullin Ramil , Aliev Ali , Matveev Vladimir , Gerasimov Vladimir , Slesarenko Nikita , Avilova Irina , Volkov Vitaly , Tverskoy Vladimir
Published: June 2023

In the present work, the effect of divinylbenzene (DVB) on the kinetics of post-radiation chemical graft polymerization styrene (St) on polyethylene (PE) film and its structural and morphological features were investigated. It has been found that the dependence of the degree of polystyrene (PS) grafting on the DVB concentration in the solution is extreme. An increase in the rate of graft polymerization at low concentrations of DVB in the solution is associated with a decrease in the mobility of the growing chains of PS. A decrease in the rate of graft polymerization at high concentrations of DVB is associated with a decrease in the rate of diffusion of St and iron(II) ions in the cross-linked network structure of macromolecules of graft PS. A comparative analysis of the IR transmission and multiple attenuated total internal reflection spectra of the films with graft PS shows that graft polymerization of St in the presence of DVB leads to the enrichment of the film surface layers in PS. These results have been confirmed by the data on the distribution of sulfur in these films after sulfonation. The micrographs of the surface of the grafted films show the formation of cross-linked local microphases of PS with fixed interfaces.
Spectral Features Differentiate Aging-Induced Changes in Parchment—A Combined Approach of UV/VIS, µ-ATR/FTIR and µ-Raman Spectroscopy with Multivariate Data Analysis
Authors: Malissa Antonia , Cappa Federica , Schreiner Manfred , Marchetti-Deschmann Martina
Published: June 2023

From the moment of production, artworks are constantly exposed to changing environmental factors potentially inducing degradation. Therefore, detailed knowledge of natural degradation phenomena is essential for proper damage assessment and preservation. With special focus on written cultural heritage, we present a study on the degradation of sheep parchment employing accelerated aging with light (295–3000 nm) for one month, 30/50/80% relative humidity (RH) and 50 ppm sulfur dioxide with 30/50/80%RH for one week. UV/VIS spectroscopy detected changes in the sample surface appearance, showing browning after light-aging and increased brightness after SO2-aging. Band deconvolution of ATR/FTIR and Raman spectra and factor analysis of mixed data (FAMD) revealed characteristic changes of the main parchment components. Spectral features for degradation-induced structural changes of collagen and lipids turned out to be different for the employed aging parameters. All aging conditions induced denaturation (of different degrees) indicated by changes in the secondary structure of collagen. Light treatment resulted in the most pronounced changes for collagen fibrils in addition to backbone cleavage and side chain oxidations. Additional increased disorder for lipids was observed. Despite shorter exposure times, SO2-aging led to a weakening of protein structures induced by transitions of stabilizing disulfide bonds and side chain oxidations.
New Phenolic Dimers from Plant Paeonia suffruticosa and Their Cytotoxicity and NO Production Inhibition
Authors: Meng Qianqian , Tong Shunyao , Zhao Yuqing , Peng Xingrong , Li Zhenghui , Feng Tao , Liu Jikai
Published: June 2023

The Paeonia suffruticosa, known as ‘Feng Dan’, has been used for thousands of years in traditional Chinese medicine. In our chemical investigation on the root bark of the plant, five new phenolic dimers, namely, paeobenzofuranones A–E (1–5), were characterized. Their structures were determined using spectroscopic analysis including 1D and 2D NMR, HRESIMS, UV, and IR, as well as ECD calculations. Compounds 2, 4, and 5 showed cytotoxicity against three human cancer cell lines, with IC50 values ranging from 6.7 to 25.1 μM. Compounds 1 and 2 showed certain inhibitory activity on NO production. To the best of our knowledge, the benzofuranone dimers and their cytotoxicity of P. suffruticosa are reported for the first time in this paper.
Photocatalytic Degradation of Food and Juices Dyes via Photocatalytic Nanomaterials Synthesized through Green Synthetic Route: A Systematic Review
Authors: Khan Kashif Ali , Shah Afzal , Nisar Jan , Haleem Abdul , Shah Iltaf
Published: June 2023

The unavailability of non-poisonous and hygienic food substances is the most challenging issue of the modern era. The uncontrolled usage of toxic colorant moieties in cosmetics and food manufacturing units leads to major threats to human life. The selection of environmentally benign approaches for the removal of these toxic dyes has gained the utmost attention from researchers in recent decades. This review article’s main aim is the focus on the application of green-synthesized nanoparticles (NPs) for the photocatalytic degradation of toxic food dyes. The use of synthetic dyes in the food industry is a growing concern due to their harmful effects on human health and the environment. In recent years, photocatalytic degradation has emerged as an effective and eco-friendly method for the removal of these dyes from wastewater. This review discusses the various types of green-synthesized NPs that have been used for photocatalytic degradation (without the production of any secondary pollutant), including metal and metal oxide NPs. It also highlights the synthesis methods, characterization techniques, and photocatalytic efficiency of these NPs. Furthermore, the review explores the mechanisms involved in the photocatalytic degradation of toxic food dyes using green-synthesized NPs. Different factors that responsible for the photodegradation, are also highlighted. Advantages and disadvantages, as well as economic cost, are also discussed briefly. This review will be advantageous for the readers because it covers all aspects of dyes photodegradation. The future feature and limitations are also part of this review article. Overall, this review provides valuable insights into the potential of green-synthesized NPs as a promising alternative for the removal of toxic food dyes from wastewater.
Nucleation and Stability of Toron Chains in Non-Centrosymmetric Magnetic Nanowires
Authors: Castillo-Sepúlveda Sebastián , Corona Rosa M. , Saavedra Eduardo , Laroze David , Espejo Alvaro P. , Carvalho-Santos Vagson L. , Altbir Dora
Published: June 2023

This work analyzes the magnetic configurations of cylindrical nanowires with a bulk Dzyaloshinskii–Moriya interaction and easy-plane anisotropy. We show that this system allows the nucleation of a metastable toron chain even when no out-of-plane anisotropy exists in the nanowire’s top and bottom surfaces, as usually required. The number of nucleated torons depends on the nanowire length and the strength of an external magnetic field applied to the system. The size of each toron depends on the fundamental magnetic interactions and can be controlled by external stimuli, allowing the use of these magnetic textures as information carriers or nano-oscillator elements. Our results evidence that the topology and structure of the torons yield a wide variety of behaviors, revealing the complex nature of these topological textures, which should present an exciting interaction dynamic, depending on the initial conditions.
The Particle-Tracking Simulation of a New Photocathode RF Gun in the Free-Electron Laser Facility, KU-FEL
Authors: Zhao Yuhao , Zen Heishun , Ohgaki Hideaki
Published: June 2023

A project is underway that aims to generate attosecond pulses via high-harmonic generation in rare gases, driven by extremely short and highly intense pulses from free-electron-laser oscillators. For this purpose, it has been planned that a new photocathode RF gun, dedicated to high-bunch-charge operation, will be installed at the KU-FEL (Kyoto University Free Electron Laser) oscillator facility. In this study, RF guns with two different structures (1.6-cell and 1.4-cell) were compared, from the perspective of exploring the possibility of introducing bunch-interval modulation, which is important for achieving high extraction efficiency in the FEL oscillator. As a result, it was confirmed that the introduction of bunch-phase modulation would be possible only in the case of the 1.6-cell RF gun. After the structure of the RF gun was decided on, particle-tracking simulations were performed, to study the electron-beam parameters using the 1.6-cell RF gun and 1 nC bunch charge. The results showed that we could obtain the peak current of 1 kA without a large degradation of the other parameters.
Density and Mass Function for Regular Rotating Electrically Charged Compact Objects Determined by Nonlinear Electrodynamics Minimally Coupled to Gravity
Authors: Dymnikova Irina
Published: June 2023

We address the question of the electromagneticdensity and the mass function for regular rotating electrically charged compact objects as determined by dynamical equations of nonlinear electrodynamics minimally coupled to gravity. The rotating electrically charged compact objects are described by axially symmetric geometry, in which their electromagnetic fields are governed by four source-free equations for two independent field components of the electromagnetic tensor Fμν, with two constraints on the integration functions. An additional condition of compatibility of four dynamical equations for two independent field functions imposes the constraint on the Lagrange derivative LF=dL/dF, directly related to the electromagnetic density. As a result, the compatibility condition determines uniquely the generic form of the electromagnetic density and the mass function for regular rotating electrically charged compact objects.
Sensing Performance of Ethanol Microfiber Probe Augmented by ZnO Nanosheet and UV Glue Film
Authors: Liu Fuhua , Dang Hongtao , Tian Ruixin , Li Jin , Wang Juan , Wang Dewen
Published: June 2023

A microfiber reflective ethanol gas sensing probe was designed and fabricated. The single-mode fiber was heated and stretched to prepare a microfiber taper, on which a mixed material of ZnO nanosheets and UV glue was built by the dip-coating method. The influencing factors on its sensing performance for ethanol have been discussed, including the dozen ratio of ZnO nanosheets, UV glue materials, and end-face morphology. As the concentration of ethanol gas increased, the intensity of the reflection spectrum increased with the responding sensitivity of 7.28 × 10−4 dBm/ppm. The exchanging efficiency of the optical signal is enhanced by the strong evanescent field of the microfiber taper. This sensing probe is convenient for high-density integration and working in a small space and is capable of high-performance monitoring for ethanol at room temperature.
Study on the Degradation of a Semi-Synthetic Lignin–Acrylic Acid Hydrogel with Common Bacteria Found in Natural Attenuation Processes
Authors: Jiménez-Torres Humberto D. , Hernández-Olmos Saira L. , Reynaga-Delgado Eire , Orozco-Guareño Eulogio
Published: June 2023

In this study, lignin was chemically modified to promote hydrogel degradation as a source of carbon and nitrogen for a bacterial consortium consisting of P. putida F1, B. cereus and, B. paramycoides. A hydrogel was synthesized using acrylic acid (AA), acrylamide (AM), and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and cross-linked with the modified lignin. The structural changes and mass loss in the hydrogel, as well as its final composition, were evaluated as functions of the growth of the selected strains in a culture broth with the powdered hydrogel. The average loss was 18.4% wt. The hydrogel was characterized using FTIR spectroscopy, scanning electronic microscopy (SEM), elemental analysis (EA), and thermogravimetric analysis (TGA) before and after bacterial treatment. FTIR showed that the carboxylic groups present in both the lignin and the acrylic acid of the hydrogel decreased during bacterial growth. The bacteria showed a preference for the biomaterial components of the hydrogel. SEM demonstrated superficial morphological changes in the hydrogel. The results reveal that the hydrogel was assimilated by the bacterial consortium while preserving the water retention capacity of the material and that the microorganisms carried out a partial biodegradation of the hydrogel. The results of the EA and TGA confirm that the bacterial consortium not only degraded the biopolymer (lignin), but also used the synthetic hydrogel as a carbon source to degrade its polymeric chains and modified original properties. This modification with lignin as a crosslinker (which is a waste product of the paper industry) is therefore proposed to promote hydrogel degradation.
Kupczynski’s Contextual Locally Causal Probabilistic Models Are Constrained by Bell’s Theorem
Authors: Gill Richard D. , Lambare Justo Pastor
Published: June 2023

In a sequence of papers, Marian Kupczynski has argued that Bell’s theorem can be circumvented if one takes correct account of contextual setting-dependent parameters describing measuring instruments. We show that this is not true. Despite first appearances, Kupczynksi’s concept of a contextual locally causal probabilistic model is mathematically a special case of a Bell local hidden variables model. Thus, even if one takes account of contextuality in the way he suggests, the Bell–CHSH inequality can still be derived. Violation thereof by quantum mechanics cannot be easily explained away: quantum mechanics and local realism (including Kupczynski’s claimed enlargement of the concept) are not compatible with one another. Further inspection shows that Kupczynski is actually falling back on the detection loophole. Since 2015, numerous loophole-free experiments have been performed, in which the Bell–CHSH inequality is violated, so, despite any other possible imperfections of such experiments, Kupczynski’s escape route for local realism is not available.