bluuebunny/crossref_metadata_2025 huggingface dataset:
Fusarium spp. in Human Disease: Exploring the Boundaries between Commensalism and Pathogenesis
Authors: Cighir Anca , Mare Anca Delia , Vultur Florina , Cighir Teodora , Pop Suzana Doina , Horvath Karin , Man Adrian
Published: June 2023

Fusarium is a large fungal genus that is widely distributed in the environment, mostly known for its plant pathogenicity. Rarely, it is involved in human pathology, where the type of infection caused is highly dependent upon the portal of entry and the immune status of the host. The study at hand aims to summarize routine methods used in diagnosing such infections as well as more advanced molecular diagnostic methods, techniques that can play a huge role in differentiating between colonization and infection when trying to decide the therapeutic outcome. Consequently, to further support our findings, two different strains (one isolated from corneal scrapings and one isolated from purulent discharge) were analyzed in a clinical context and thoroughly tested using classical and modern diagnostic methods: identification by macroscopical and microscopical examinations of the culture and mass spectrometry, completed by molecular methods such as PCR for trichothecene and ERIC-PCR for genetic fingerprinting. Isolation of a clinically relevant Fusarium spp. from a sample still remains a diagnostic challenge for both the clinician and the microbiologist, because differentiating between colonization and infection is very strenuous, but can make a difference in the treatment that is administered to the patient.
Artificial Intelligence for Classifying the Relationship between Impacted Third Molar and Mandibular Canal on Panoramic Radiographs
Authors: Lo Casto Antonio , Spartivento Giacomo , Benfante Viviana , Di Raimondo Riccardo , Ali Muhammad , Di Raimondo Domenico , Tuttolomondo Antonino , Stefano Alessandro , Yezzi Anthony , Comelli Albert
Published: June 2023

The purpose of this investigation was to evaluate the diagnostic performance of two convolutional neural networks (CNNs), namely ResNet-152 and VGG-19, in analyzing, on panoramic images, the rapport that exists between the lower third molar (MM3) and the mandibular canal (MC), and to compare this performance with that of an inexperienced observer (a sixth year dental student). Utilizing the k-fold cross-validation technique, 142 MM3 images, cropped from 83 panoramic images, were split into 80% as training and validation data and 20% as test data. They were subsequently labeled by an experienced radiologist as the gold standard. In order to compare the diagnostic capabilities of CNN algorithms and the inexperienced observer, the diagnostic accuracy, sensitivity, specificity, and positive predictive value (PPV) were determined. ResNet-152 achieved a mean sensitivity, specificity, PPV, and accuracy, of 84.09%, 94.11%, 92.11%, and 88.86%, respectively. VGG-19 achieved 71.82%, 93.33%, 92.26%, and 85.28% regarding the aforementioned characteristics. The dental student’s diagnostic performance was respectively 69.60%, 53.00%, 64.85%, and 62.53%. This work demonstrated the potential use of deep CNN architecture for the identification and evaluation of the contact between MM3 and MC in panoramic pictures. In addition, CNNs could be a useful tool to assist inexperienced observers in more accurately identifying contact relationships between MM3 and MC on panoramic images.
An Evaluation of the Mechanical Properties of a Hybrid Composite Containing Hydroxyapatite
Authors: Klimek Leszek , Kopacz Karolina , Śmielak Beata , Kula Zofia
Published: June 2023

There is currently a lack of scientific reports on the use of composites based on UDMA resin containing HAp in conservative dentistry. The aim of this study was therefore to determine the effect of hydroxyapatite content on the properties of a hybrid composite used in conservative dentistry. This paper compares a commercial hybrid composite with experimental composites treated with 2% by weight (b/w), 5% b/w, and 8% b/w hydroxyapatite. The composites were subjected to bending strength, compression, and diametrical compression tests, as well as those for impact strength, hardness, and tribological wear. The obtained results were subjected to statistical analysis. Increased hydroxyapatite was found to weaken the mechanical properties; however, 2% b/w and 5% b/w hydroxyapatite powder was found to achieve acceptable results. The statistical analysis showed no significant differences. HAp is an effective treatment for composites when applied at a low concentration. Further research is needed to identify an appropriate size of HAp particles that can be introduced into a composite to adequately activate the surface and modification its composition.
N, S, O Self-Doped Carbon Derived from Grapefruit Peel for High-Performance Supercapacitors
Authors: Wang Yi , Wang Liangqun , Lu Xihong
Published: June 2023

The development of high-capacity carbon for supercapacitors is highly desirable but challenging. In this work, we design a N, S, O self-doped carbon electrode (NSOC-800) with high capacitance and good stability via the carbonization of grapefruit peel via a one-step KOH activation method without extra dopants. The existence of heteroatoms enables the NSOC-800 to have a high specific capacitance of 280 F/g and a great cycling performance, with 90.1% capacitance retention after 5000 cycles. Moreover, the symmetric supercapacitor with NSOC-800 electrodes delivers a maximum energy density of 5 Wh/kg with a power density of 473 W/kg. Such a promising method to achieve carbon materials with self-doping heteroatwoms is of great significance for developing highly efficient electrodes for energy storage devices.
Protective Effect and Mechanisms of Eckol on Chronic Ulcerative Colitis Induced by Dextran Sulfate Sodium in Mice
Authors: Liao Mengfan , Wei Songyi , Hu Xianmin , Liu Juan , Wang Jun
Published: June 2023

The use of functional foods and their bioactive components is receiving increasing attention as a complementary and alternative therapy for chronic ulcerative colitis (UC). This study explored the protective effect and mechanisms of Eckol, a seaweed-derived bioactive phlorotannin, on the dextran sodium sulfate (DSS)-induced chronic UC in mice. Eckol (0.5–1.0 mg/kg) reduced DSS-enhanced disease activity indexes, and alleviated the shortening of colon length and colonic tissue damage in chronic UC mice. The contents of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 were significantly decreased, and the level of anti-inflammatory IL-10 was enhanced in the serum and colonic tissues collected from Eckol-treated mice compared with the DSS controls. Eckol administration significantly reduced the number of apoptotic cells and the expression of cleaved Caspase-3, and increased the B-cell lymphoma-2 (Bcl-2)/B-cell lymphoma-2- associated X (Bax) ratio in DSS-challenged colons. There were more cluster of differentiation (CD)11c+ dendritic cells and CD8+ T cells, and less CD4+ T cells infiltrated to inflamed colonic tissues in the Eckol-treated groups. Expression of colonic Toll-like receptor 4 (TLR4), nuclear factor kappa-B (NF-κB) p65, phosphorylated-signal transducer and activator of transcription (pSTAT)3 was significantly down-regulated by Eckol compared with the DSS-challenged group. In conclusion, our data suggest that Eckol appeared to be a potential functional food ingredient for protection against chronic UC. The anti-colitis mechanisms of Eckol might be attributed to the down-regulation of the TLR4/NF-κB/STAT3 pathway, inhibition of inflammation and apoptosis, as well as its immunoregulatory activity.
Hypermagnesemia in Clinical Practice
Authors: Aal-Hamad Aya Hasan , Al-Alawi Abdullah M. , Kashoub Masoud Salim , Falhammar Henrik
Published: June 2023

Hypermagnesemia is a relatively uncommon but potentially life-threatening electrolyte disturbance characterized by elevated magnesium concentrations in the blood. Magnesium is a crucial mineral involved in various physiological functions, such as neuromuscular conduction, cardiac excitability, vasomotor tone, insulin metabolism, and muscular contraction. Hypomagnesemia is a prevalent electrolyte disturbance that can lead to several neuromuscular, cardiac, or nervous system disorders. Hypermagnesemia has been associated with adverse clinical outcomes, particularly in hospitalized patients. Prompt identification and management of hypermagnesemia are crucial to prevent complications, such as respiratory and cardiovascular negative outcomes, neuromuscular dysfunction, and coma. Preventing hypermagnesemia is crucial, particularly in high-risk populations, such as patients with impaired renal function or those receiving magnesium-containing medications or supplements. Clinical management of hypermagnesemia involves discontinuing magnesium-containing therapies, intravenous fluid therapy, or dialysis in severe cases. Furthermore, healthcare providers should monitor serum magnesium concentration in patients at risk of hypermagnesemia and promptly intervene if the concentration exceeds the normal range.
What Is the Optimal Digoxin Level? Challenging Case of Fetal Atrial Flutter Treatment in a Monochorionic Diamniotic Twin
Authors: Kim Soo Jung , Jeon Hee Do , Shim So-Yeon , Kim Yi-Seul , Park Mi-Hye , Lee Kyung A.
Published: June 2023

Background: Atrial flutter is an infrequent yet potentially fatal arrhythmia. Digoxin is the preferred first-line treatment for fetal atrial flutter due to its efficacy and favorable safety profile. The optimal digoxin serum target level for neonatal atrial flutter management remains uncertain, with the standard target level ranging from 1.0 to 2.0 ng/mL due to potential toxicity concerns above this threshold. Case Presentation: We present a case of atrial flutter in a fetus within a monochorionic diamniotic (MCDA) twin pregnancy that was successfully managed using a higher-than-standard target level of digoxin. A 34-year-old nulliparous woman was referred to our institution at 31 + 3 weeks of gestation due to fetal distress in an MCDA twin pregnancy. Fetal echocardiography revealed a ventricular rate of 214 bpm in twin A, while twin B exhibited no abnormal findings. Conclusions: Our case highlights a distinct correlation between the serum digoxin level and its impact on atrial flutter. A higher target serum level of digoxin may be necessary to achieve sinus conversion due to the unique maternal and fetal circulatory characteristics in MCDA pregnancies.
Incidence of Lower Extremity Amputation in Romania: A Nationwide 5-Year Cohort Study, 2015–2019
Authors: Rusu Emilia , Coman Horațiu , Coșoreanu Andrada , Militaru Ana-Maria , Popescu-Vâlceanu Horațiu-Cristian , Teodoru Ileana , Mihai Doina-Andrada , Elian Viviana , Gavan Norina Alinta , Radulian Gabriela
Published: June 2023

Background and Objectives: The primary objective of this study was to investigate the incidence of lower extremity amputations (LEAs) in a representative population from Romania, in both diabetic and non-diabetic adults, including trauma-related amputations. The secondary objective was to evaluate the trends in LEAs and the overall ratio of major-to-minor amputations. Material and Methods: The study was retrospective and included data from the Romanian National Hospital Discharge Records, conducted between 1 January 2015 and 31 December 2019. Results: The overall number of cases with LEAs was 88,102, out of which 38,590 were aterosclerosis-related LEAs, 40,499 were diabetes-related LEAs, and 9013 were trauma-related LEAs, with an ascending trend observed annually for each of these categories. Of the total non-traumatic amputations, 51.2% were in patients with diabetes. Most LEAs were in men. The total incidence increased from 80.61/100,000 in 2015 to 98.15/100,000 in 2019. Conclusions: Our study reported a 21% increase in total LEAs, 22.01% in non-traumatic LEAs, and 19.65% in trauma-related amputation. The minor-to-major amputation ratio increased over the study period in patients with diabetes. According to these findings, it is estimated that currently, in Romania, there is one diabetes-related amputation every hour and one non-traumatic amputation every 30 min.
Hypo-Osmotic Stress and Pore-Forming Toxins Adjust the Lipid Order in Sheep Red Blood Cell Membranes
Authors: Whiting Rose , Stanton Sevio , Kucheriava Maryna , Smith Aviana R. , Pitts Matt , Robertson Daniel , Kammer Jacob , Li Zhiyu , Fologea Daniel
Published: June 2023

Lipid ordering in cell membranes has been increasingly recognized as an important factor in establishing and regulating a large variety of biological functions. Multiple investigations into lipid organization focused on assessing ordering from temperature-induced phase transitions, which are often well outside the physiological range. However, particular stresses elicited by environmental factors, such as hypo-osmotic stress or protein insertion into membranes, with respect to changes in lipid status and ordering at constant temperature are insufficiently described. To fill these gaps in our knowledge, we exploited the well-established ability of environmentally sensitive membrane probes to detect intramembrane changes at the molecular level. Our steady state fluorescence spectroscopy experiments focused on assessing changes in optical responses of Laurdan and diphenylhexatriene upon exposure of red blood cells to hypo-osmotic stress and pore-forming toxins at room temperature. We verified our utilized experimental systems by a direct comparison of the results with prior reports on artificial membranes and cholesterol-depleted membranes undergoing temperature changes. The significant changes observed in the lipid order after exposure to hypo-osmotic stress or pore-forming toxins resembled phase transitions of lipids in membranes, which we explained by considering the short-range interactions between membrane components and the hydrophobic mismatch between membrane thickness and inserted proteins. Our results suggest that measurements of optical responses from the membrane probes constitute an appropriate method for assessing the status of lipids and phase transitions in target membranes exposed to mechanical stresses or upon the insertion of transmembrane proteins.
A Rapid, Open-Source CCT Predictor for Low-Alloy Steels, and Its Application to Compositionally Heterogeneous Material
Authors: Collins Joshua , Piemonte Martina , Taylor Mark , Fellowes Jonathan , Pickering Ed
Published: June 2023

The ability to predict transformation behaviour during steel processing, such as primary heat treatments or welding, is extremely beneficial for tailoring microstructures and properties to a desired application. In this work, a model for predicting the continuous cooling transformation (CCT) behaviour of low-alloy steels is developed, using semi-empirical expressions for isothermal transformation behaviour. Coupling these expressions with Scheil’s additivity rule for converting isothermal to non-isothermal behaviour, continuous cooling behaviour can be predicted. The proposed model adds novel modifications to the Li model in order to improve CCT predictions through the addition of a carbon-partitioning model, thermodynamic boundary conditions, and a Koistinen–Marburger expression for martensitic behaviour. These modifications expanded predictions to include characteristic CCT behaviour, such as transformation suppression, and an estimation of the final constituent fractions. The proposed model has been shown to improve CCT predictions for EN3B, EN8, and SA-540 B24 steels by better reflecting experimental measurements. The proposed model was also adapted into a more complex simulation that considers the chemical heterogeneity of the examined SA-540 material, showing a further improvement to CCT predictions and demonstrating the versatility of the model. The model is rapid and open source.
Effect of V2O5 on Consolidation, Reduction, and Softening-Melting Behavior of High-Cr Vanadium Titanomagnetite
Authors: Liu Jianxing , Xing Zhenxing , Wang Xuyang , Cheng Gongjin , Xue Xiangxin
Published: June 2023

Vanadium titanomagnetite is an important mineral resource. It is a raw material for ironmaking, vanadium extraction, strategic metal titanium production, and titanium dioxide production. In this study, high chromium vanadium titanomagnetite (High-Cr VTM) and ordinary iron ore were used as raw materials for pelletizing. The effect of V2O5 on the preparation and properties of High-Cr VTM pellets was studied. The influence of V2O5 on the properties of the green pellets, the compressive strength of oxidized pellets, the reduction swelling index and reduction degree, softening-melting behavior, and the migration law of Fe, Ti, and Cr in the reduction process were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that with the increase in V2O5 content, the properties of the green pellets basically showed a trend of first decreasing and then increasing but all met the basic requirements of pelletizing. When the added amount of V2O5 in the pellet was 6%, the compressive strength of the oxidized pellet was the lowest at only 2565 N/pellet but it still met the quality requirements for pellets in blast furnace production. As the dosage of V2O5 increased, the reduction swelling index and reduction degree of the pellets showed a trend of first increasing and then decreasing. The addition of V2O5 can increase the softening initial temperature, softening final temperature, melting start temperature, and dripping temperature of the High-Cr VTM pellets, narrowing the softening interval, and expanding the melting dripping interval. The experimental results provided a data reference for revealing the influence of V2O5 on High-Cr VTM pellets during the blast furnace smelting process.
The Influence of Alloying Elements on the Microstructure and Properties of Al-Si-Based Casting Alloys: A Review
Authors: Callegari Bruna , Lima Tiago Nunes , Coelho Rodrigo Santiago
Published: June 2023

The excellent casting behavior and mechanical and corrosion properties of aluminum-silicon (Al-Si)-based alloys make them ideal for the manufacture of lightweight components with complex geometries. However, these properties depend directly on their microstructure, which, in its turn, is strongly affected by the composition of the alloy, among other factors. Several elements can be added to the material aiming to promote microstructural changes, e.g., grain refinement, optimization of phase morphology and distribution, and precipitation strengthening. Efforts are continuously put into such enhancements of cast Al alloys since they lead to quality improvements that allow for weight reduction and safety increase. Considering the technological relevance of the subject, this paper provides an overview of the research focused on the addition of alloying elements to these alloys, with a greater focus on Al-Si-based systems and the comprehension of the effects of these additions on their microstructure and properties.
Microstructure, Hardness, and Linear Reciprocating Sliding Wear Response of Directionally Solidified Al–(2.5, 3.5, 4.5)Cu–(0.25, 0.50)Cr Alloys
Authors: Lantmann Rafael V. , Mariante André M. S. , Pinheiro Tiago V. , da Costa Eleani M. , dos Santos Carlos A.
Published: June 2023

Aluminum alloys containing transition metal alloying elements have attracted interest from researchers. The effect of Cr additions of 0.25 and 0.50% on the thermal profile, microstructure, hardness, and linear reciprocating sliding wear response of as-cast hypoeutectic Al–Cu alloys with 2.5, 3.5, and 4.5% Cu (wt.%) was investigated. The binary Al–Cu and ternary Al–Cu–Cr alloys were directionally solidified under upward non-steady state heat transfer conditions using a dedicated solidification apparatus. Thermal analysis based on differential thermal analysis (DTA) and cooling curve profiles was performed to determine solidification thermal parameters such as Liquidus temperature (TL), transformation enthalpy (ΔH), and liquid cooling rate (ṪL). Samples extracted from the solidified ingots were submitted to optical microscopy, hardness measurement, and linear reciprocating sliding wear test using a high-frequency reciprocating rig (HFRR). The results showed a decrease at the beginning of solidification (TL) and of the transformation enthalpy (ΔH) when both alloy Cu and Cr contents increased, with a higher influence of Cu. The addition of Cu decreased cooling rates, whereas the increase in the alloy Cr concentration showed an opposite behavior, increasing cooling rates. The refinement of the primary dendrite arm spacing (λ1), as a consequence of the increase in alloying elements and solidification cooling rates, enhanced the hardness of the alloys, with the maximum value of 58 HB achieved in the ternary Al–4.5Cu–0.50Cr alloy. The wear tests indicated a better response to wear associated with microstructure refinement for the alloys with 2.5% Cu, for both Cr contents, an almost constant behavior for the 3.5% Cu alloys, and an opposite performance for the alloys with 4.5% Cu alloys that showed better wear resistance with coarsening of the λ1 and with the increase in the amount of the eutectic microconstituent.
Microstructure and Properties of Non-Equiatomic Ni10Cr6WFe9TiAlx High-Entropy Alloys Combined with High Strength and Toughness
Authors: Yang Xigang , He Lin , Li Erhong , Yang Chenglong
Published: June 2023

High-entropy alloys (HEAs) with excellent mechanical properties have broad application scope and application prospects. However, it is difficult to obtain the optimized element composition, based on the traditional equiatomic or near-equiatomic statistical analysis of the phase selection rules. The non-equiatomic HEAs have abundant constituents combination by optimizing the type and content of elements. In this study, Ni10Cr6WFe9TiAlx (x = 0, 1.0 and 1.5, at.%) HEAs were prepared by vacuum arc melting. The effect of Al content x on microstructure and mechanical properties of HEAs was systematically studied. The results show that the HEAs are composed mainly of face-centered cubic (FCC) with hexagonal Al2W phase. The increase of Al content promotes the formation of the hexagonal Al2W phase. When the Al mole content is 1.0, the Ni10Cr6WFe9TiAl HEA material has achieved superior mechanical properties. The alloy exhibited a high ultimate tensile strength of 741 MPa and a large total elongation of 46%. The improvement in the mechanical properties of the Ni10Cr6WFe9TiAl HEA is mainly attributed to the precipitation strengthening of the high-density Al2W phase. This work provides a reference for the future design of Al2W precipitation-strengthened non-equiatomic HEAs with ideal properties.
Pilot Study on the Use of Untargeted Metabolomic Fingerprinting of Liquid-Cytology Fluids as a Diagnostic Tool of Malignancy for Thyroid Nodules
Authors: D’Andréa Grégoire , Jing Lun , Peyrottes Isabelle , Guigonis Jean-Marie , Graslin Fanny , Lindenthal Sabine , Sanglier Julie , Gimenez Isabel , Haudebourg Juliette , Vandersteen Clair , Bozec Alexandre , Guevara Nicolas , Pourcher Thierry
Published: June 2023

Although it is the gold standard for assessing the malignancy of thyroid nodules (TNs) preoperatively, the cytological analysis of fine-needle aspiration cytology (FNAC) samples results in 20–30% of cases in indeterminate lesions (ITNs). As two-thirds of these lesions will appear benign after diagnostic surgery, improved preoperative diagnostic methods need to be developed. In this pilot study, we evaluate if the metabolomic profiles of liquid-based (CytoRich®) FNAC samples of benign and malignant nodules can allow the molecular diagnosis of TNs. We performed untargeted metabolomic analyses with CytoRich® FNAC in a monocentric retrospective study. The cohort was composed of cytologically benign TNs, histologically benign or papillary thyroid carcinomas (PTCs) cytologically ITNs, and suspicious/malignant TNs histologically confirmed as PTCs. The diagnostic performance of the identified metabolomic signature was assessed using several supervised classification methods. Seventy-eight patients were enrolled in the study. We identified 7690 peaks, of which 2697 ions were included for further analysis. We selected a metabolomic signature composed of the top 15 metabolites. Among all the supervised classification methods, the supervised autoencoder deep neural network exhibited the best performance, with an accuracy of 0.957 (0.842–1), an AUC of 0.945 (0.833–1), and an F1 score of 0.947 (0.842–1). Here, we report a promising new ancillary molecular technique to differentiate PTCs from benign TNs (including among ITNs) based on the metabolomic signature of FNAC sample fluids. Further studies with larger cohorts are now needed to identify a larger number of biomarkers and obtain more robust signatures.
A Mass Spectrometry Database for Sea Cucumber Triterpene Glycosides
Authors: Popov Roman S. , Ivanchina Natalia V. , Silchenko Alexandra S. , Avilov Sergey A. , Kalinin Vladimir I. , Malyarenko Timofey V. , Stonik Valentin A. , Dmitrenok Pavel S.
Published: June 2023

Sea cucumber triterpene glycosides are a class of secondary metabolites that possess distinctive chemical structures and exhibit a variety of biological and pharmacological activities. The application of MS-based approaches for the study of triterpene glycosides allows rapid evaluation of the structural diversity of metabolites in complex mixtures. However, the identification of the detected triterpene glycosides can be challenging. The objective of this study is to establish the first spectral library containing the mass spectra of sea cucumber triterpene glycosides using ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry. The library contains the electrospray ionization tandem mass spectra and retention times of 191 triterpene glycosides previously isolated from 15 sea cucumber species and one starfish at the Laboratory of the Chemistry of Marine Natural Products of the G.B. Elyakov Pacific Institute of Bioorganic Chemistry. In addition, the chromatographic behavior and some structure-related neutral losses in tandem MS are discussed. The obtained data will accelerate the accurate dereplication of known triterpene glycosides and the annotation of novel compounds, as we demonstrated by the processing of LC-MS/MS data of Eupentacta fraudatrix extract.
Metabolite Profiling of External and Internal Petals in Three Different Colors of Tea Flowers (Camellia sinensis) Using Widely Targeted Metabolomics
Authors: Zhang Tao , Ma Xue , Zhou Yuanyuan , Yang Hui , Wang Yuxin , Chen Taolin , Chen Qincao , Deng Yanli
Published: June 2023

The flower is the reproductive organ of the tea plant, while it is also processed into different kinds of products and thus of great significance to be utilized. In this study, the non-volatile secondary metabolites in the internal and external petals of white, white and pink, and pink tea flowers were studied using a widely targeted metabolomics method with ultra-high liquid chromatography–tandem mass spectrometry (UPLC-MS/MS). A total of 429 metabolites were identified, including 195 flavonoids, 121 phenolic acids, 40 alkaloids, 29 lignans and coumarins, 19 tannins, 17 terpenoids, and 8 other metabolites. The metabolites in the internal and external petals of different colored flowers showed great changes in flavonoids. Most flavonoids and all tannins in the internal petals were higher compared with the external petals. Some phenolic acids were more accumulated in the external petals, while others showed opposite trends. The pink tea flower contained more flavonoids, alkaloids, lignans, coumarins, terpenoids, and tannins compared with white tea flowers. In addition, cyanidin-3-O-glucoside was more accumulated in the external petals of the pink flower, indicating that anthocyanin may be the main reason for the color difference between the pink and white tea flower. The enriched metabolic pathways of different colored flowers were involved in flavonoid biosynthesis, glycine, serine and threonine metabolism, glycerophospholipid metabolism, and phenylpropanoid biosynthesis. The findings of this study broaden the current understanding of non-volatile compound changes in tea plants. It is also helpful to lay a theoretical foundation for integrated applications of tea flowers.
Synthesis and Characterization of Zinc Oxide Nanoparticles at Different pH Values from Clinopodium vulgare L. and Their Assessment as an Antimicrobial Agent and Biomedical Application
Authors: Arif Hajira , Qayyum Sidra , Akhtar Wasim , Fatima Iram , Kayani Waqas Khan , Rahman Khursheed Ur , Al-Onazi Wedad A. , Al-Mohaimeed Amal M. , Bangash Naila Khan , Ashraf Nasra , Razak Sarah Abdul , Kamal Asif , Ali Sajid
Published: June 2023

The current study attempts to evaluate the formation, morphology, and physico-chemical properties of zinc oxide nanoparticles (ZnO NPs) synthesized from Clinopodium vulgare extract at different pH values and to investigate their antimicrobial and biomedical application potential. The reduction of zinc ions to ZnO NPs was determined by UV spectra, which revealed absorption peaks at 390 nm at pH 5 and 348 nm at pH 9, respectively. The spherical morphology of the nanoparticles was observed using scanning electron microscopy (SEM), and the size was 47 nm for pH 5 and 45 nm for pH 9. Fourier-transformed infrared spectroscopy (FTIR) was used to reveal the presence of functional groups on the surface of nanoparticles. The antibacterial activity was examined against Staphylococcus aureus, Streptococcus pyogenes, and Klebsiella pneumonia via the agar-well diffusion method. Comparatively, the highest activities were recorded at pH 9 against all bacterial strains, and among these, biogenic ZnO NPs displayed the maximum inhibition zone (i.e., 20.88 ± 0.79 mm) against S. aureus. ZnO NPs prepared at pH 9 exhibited the highest antifungal activity of 80% at 25 mg/mL and antileishmanial activity of 82% at 400 mg/mL. Altogether, ZnO NPs synthesized at pH 9 show promising antimicrobial potential and could be used for biomedical applications.
Graphene Oxide Paper Manipulation of Micro-Reactor Drops
Authors: Song Zhixiong , Lin Eric Shen , Uddin Md Hemayet , Abid Hassan Ali , Ong Jian Wern , Ng Tuck Wah
Published: June 2023

Digital microfluidics, which relies on the movement of drops, is relatively immune to clogging problems, making it suited for micro-reactor applications. Here, graphene oxide paper of 100 μm thickness, fabricated by blade coating sedimented dispersions onto roughened substrates, followed by drying and mechanical exfoliation, was found to be relatively free of cracks and curling. It also exhibited high wettability and elasto-capillary characteristics. Possessing low enough stiffness, it could rapidly and totally self-wrap water drops of 20 μL volume placed 2 mm from its edge when oriented between 0 and 60° to the horizontal. This complete wrapping behavior allowed drops to be translated via movement of the paper over long distances without dislodgement notwithstanding accelerations and decelerations. An amount of 2 drops that were wrapped with separate papers, when collided with each other at speeds up to 0.64 m/s, were found to eschew coalescence. This portends the development of robust digital microfluidic approaches for micro-reactors.
A Wide-Band Antenna with Circular Polarization Utilizing a U-Shaped Radiator and Parasitic Strip for Wireless Communications
Authors: Yousef Basma M. , Ameen Allam M. , Alanazi Meshari D. , Rajagopal Maheswar , Ibrahim Ahmed A.
Published: June 2023

A circularly polarized (CP) and wide-band monopole antenna with a miniaturized size is suggested in this study. The suggested structure is composed of a U-shaped radiator on the front side, a partial ground plane with two rectangle slots, and a quadrilateral-shaped parasitic strip on the back side of the FR4 substrate. A wide-band operation with S11 ≤ −10 dB was achieved by regulating the radiator and the partial ground that was placed on the second side of the antenna substrate. The CP was achieved when excited two modes with the same amplitude and a 90° phase difference. This could be generated by regulating the slots’ dimensions in the ground plane. Moreover, a quadrilateral-shaped parasitic strip placed on the second side with the partial ground was utilized to extend the 3 dB axial ratio (AR) bandwidth. The suggested structure is simulated, prototyped, and measured to confirm the desired requirements with a total size of 30 × 32 mm2 (0.4 × 0.42 λ0 at 4 GHz). The tested outcomes have a bandwidth of S11 ≤ −10 dB (81.25%) (5.2 GHz, 3.8–9 GHz) and a 3 dB axial ratio (AR) bandwidth (30.7%) (1.63 GHz, 4.48–6.11 GHz). The antenna’s different parameters are discussed, which recommend the suggested antenna to be used in UWB, sub 6 GHz, and WLAN wireless applications.
Sediment Texture, Geochemical Variation, and Ecological Risk Assessment of Major Elements and Trace Metals in the Sediments of the Northeast Persian Gulf
Authors: Vaezi Alireza , Lak Razyeh
Published: June 2023

This study presents a comprehensive analysis of sediment texture along with geochemical variation, potential sources, and ecological risk assessment of major elements and trace metals in the bottom sediments of Iranian territorial waters situated in the northeast Persian Gulf. To achieve this, diverse laboratory methods, GIS techniques, statistical analyses, and index analysis approaches were employed. Over 50% of the sediment particles are mud, while one-third are sand-sized particles, primarily composed of skeletal fragments. The sediment’s elements concentrations were ranked in descending order as Ca > Al > Fe > Sr > Mn > Ba > Cr > Ni > V > Zn > Cu > Pb > As > Co > Mo > Cd. Cluster analysis revealed strong correlations among Al-Ni-Cr-V, Cd-Cu-Zn-Pb, Ba-Fe, silt-clay, and Ca-Sr. Calcium and strontium showed extremely severe enrichment due to high content of carbonate matter. Arsenic and Mo were significantly enriched, while Ba, V, Co, Zn, and Cu demonstrated moderate enrichment. Nevertheless, all the sampling stations were classified as having zero to very low levels of contamination, indicating a low potential ecological risk. Arsenic emerged as the primary contributor to the ecological risk index. Notably, no strong correlation was found between As, Mo, and other elements, indicating that As and Mo likely originate from distinct sources.
Study on the Mechanism and Prevention of Frequent Mine Seismic Events in Goaf Mining under a Multi-Layer Thick Hard Roof: A Case Study
Authors: Wang Bo , Feng Guorui , Gao Zhongxiang , Ma Junpeng , Zhu Sitao , Bai Jinwen , Li Zhu , Wu Wenda
Published: June 2023

Mine seismic events are an inevitable dynamic phenomenon occurring in deep mines. A scientific and rational method is needed to evaluate and understand mine seismicity and its induced disasters. In the Ordos mining area of North China, multiple groups of thick hard-bedded sandstone formations commonly exist in the overlying strata of Jurassic coal seams. In recent years, frequent mine seismic events in many large mines of Ordos have resulted in suspended or limited production, which seriously threatens the safe and efficient operation of 10-million-ton modern mines in China. Therefore, taking the frequent occurrence of mine seismic events in the mining process of goaf working face with a multi-layer thick hard roof in Ordos mine as the research background, this study investigated the mechanism and prevention of mine seismic in goaf working face with the methods of case study, theoretical analysis and field monitoring. The following conclusions are made: when the goaf working face is mined, an “advanced and lateral” L-form roof forms under the coupled influence of the lateral suspension plate formed above the upper working face and the roof of the working face. Due to the common influence from “advanced and lateral” L-form roof activation, the gradually breaking multi-layer thick hard roof, thick hard roof group bending and prying effects, in addition to excessively fast or uneven mining speed, mine seismic events will occur frequently when the exceedance warning index (EWI) is breeched. On this basis, coordinated blasting to break the roof along two roadways and within the working face is put forward as a measure with the purpose of preventing and controlling mine seismic events, and a robust effect on mine seismic reduction and disaster prevention is obtained in field application. The research results can serve as a reference for the development and application of mine seismic mechanism and blasting vibration reduction technology on the working face where there is a multi-layer thick hard roof, thereby supporting a strategy of promoting the resource development and energy security of deep mines.
Strength Development and Durability of Metakaolin Geopolymer Mortars Containing Pozzolans under Different Curing Conditions
Authors: Işıkdağ Burak , Yalghuz Mohammad Rahim
Published: June 2023

This study presents the strength development and durability of heat and non-heat-cured geopolymer mortars (GMs) produced using metakaolin (MK), ground granulated blast-furnace slag (GGBFS), silica fume (SF), ground calcined perlite (GCP), raw perlite (RP), potassium hydroxide (KOH), sodium metasilicate (Na2SiO3), standard sand, and tap water. An optimal combination of MK with various pozzolans and constant solid/liquid and alkaline activator ratios were determined. It was found that the GMs, including MK and GGBFS with a 1.45 solid/liquid ratio and 2.0 alkaline activator ratio, resulted in compressive strength at 88 MPa. Analysis of GMs was performed using scanning electron microscopy (SEM), EDX (Energy Scattered X-ray Spectrophotometer), and X-ray diffraction (XRD). According to the results obtained, mainly alumino-silicate-based formation, potassium from KOH solution, and calcium from GGBFS were determined. The SEM images showed that the grains with high silica content, approximately 6–7 µm in size, are quartz crystals and embedded in the gel structure. The heat-cured GMs were exposed to MgSO4, Na2SO4, and HCl solutions for the durability tests. The strength of the heat-cured GMs was higher than the non-heat-cured GMs, and the durability of the heat-cured GMs was found as sufficient. The use of pozzolans in GMs resulted in improvements in terms of strength and durability.
The Color Formation of “Lumu Stone” in the Weathering Processes: The Role of Secondary Hematite and Goethite
Authors: Zheng Jinyu , Chen Tao , Han Wen , Xu Xing , Yan Xuejun , Yan Jun
Published: June 2023

Rocks and minerals buried in the earth’s surface usually undergo weathering processes and change color in the burying environment. A kind of yellow Chinese stamp stone named “Lumu stone”, which is buried in a yellowish weathering crust (yellowish soil), was selected to investigate its color changes in the weathering processes. In this study, the appearance features, mineral components, micromorphology, spectroscopy characteristics, and color causation of the “Lumu stone” were studied by using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), an electron probe microanalyzer (EPMA), a laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS), and a UV-Visible (UV-Vis) spectrum. The “Lumu stone” usually exhibits a darker yellow outer layer and a lighter yellow core, suggesting that yellow color permeated into the stone from the surface to the core gradually and the color is secondary forming. The results from XRD and SEM show the studied samples are mainly composed of dickite and illite. The individual particles of the dickite and illite are about 2–5 μm, randomly distributing in the three-dimensional space and constituting voids among the particles. The acid pickling experiments using HCl coupled with KSCN confirmed that the mineral phases that caused the yellow color of the matrix are iron oxide and hydroxide. On the other hand, goethite and hematite were observed gathering in the yellow and brown-red cracks on the “Lumu stone” by SEM study. However, iron oxide and hydroxide in the matrix were difficult to observe and detect among the dickite and illite aggregates by SEM and XRD methods. It indicates that they may be nanoscale in size and very low in content. According to the calculation of the second derivative of Kubelka-Munk (K-M) transformed diffuse reflection spectroscopy (DRS) curves obtained from UV-Vis, the characteristic peaks of goethite and hematite were found in the yellow matrix, and their contributions to the color were confirmed. The concentrations of goethite and hematite were calculated to be 0.32 to 1.87 g/kg and 0.22 to 0.93 g/kg in the studied samples, respectively. In this study, a series of methods were employed to detect very low levels of goethite and hematite in the samples undergoing weathering processes. Additionally, nanoscale goethite and hematite were considered newly formed minerals when buried in the weathering processes and may gradually move into the voids among phyllosilicate particles. Therefore, they turned the “Lumu stone” yellow.
Adding Value to Mine Waste through Recovery Au, Sb, and As: The Case of Auriferous Tailings in the Iron Quadrangle, Brazil
Authors: Lemos Mariana Gazire , Valente Teresa Maria , Marinho Reis Amélia Paula , Ferreira Fonseca Rita Maria , Guabiroba Fernanda , da Mata Filho José Gregorio , Magalhães Marcus Felix , Delbem Itamar Daniel , Rebelo Diório Giovana
Published: June 2023

From the colonial era to modern times, gold mining has played a crucial role in shaping Brazil’s economy, culture, and landscape, particularly in the Iron Quadrangle region. Therefore, resulting waste has accumulated in tailings structures, either from deactivated circuits or plants still in production. The present study reveals the potential assessed based on a set of metallurgical tests, assuming specific scenarios depending on the occurrence modes of interesting economic elements. For Au, calcination, leaching, and flotation are promising techniques to recover this element. Tests indicated that toxic elements such as Sb and As could be effectively reused in the form of glass. The generation of other products from dry cleaning techniques was not effective but promising since there was an enrichment of elements with Au, Fe, Al, and K in specific fractions.
Antioxidant and Antidiabetic Properties of Phlorotannins from Ascophyllum nodosum Seaweed Extracts
Authors: Gisbert Mauro , Franco Daniel , Sineiro Jorge , Moreira Ramón
Published: June 2023

Seaweeds have gained considerable attention in recent years due to their potential health benefits and high contents of bioactive compounds. This review focuses on the exploration of seaweed’s health-promoting properties, with particular emphasis on phlorotannins, a class of bioactive compounds known for their antioxidant and antidiabetic properties. Various novel and ecofriendly extraction methods, including solid–liquid extraction, ultrasound-assisted extraction, and microwave-assisted extraction are examined for their effectiveness in isolating phlorotannins. The chemical structure and isolation of phlorotannins are discussed, along with methods for their characterization, such as spectrophotometry, nuclear magnetic resonance, Fourier transform infrared spectroscopy, and chromatography. Special attention is given to the antioxidant activity of phlorotannins. The inhibitory capacities of polyphenols, specifically phlorotannins from Ascophyllum nodosum against digestive enzymes, such as α-amylase and α-glucosidase, are explored. The results suggest that polyphenols from Ascophyllum nodosum seaweed hold significant potential as enzyme inhibitors, although the inhibitory activity may vary depending on the extraction conditions and the specific enzyme involved. In conclusion, seaweed exhibits great potential as a functional food ingredient for promoting health and preventing chronic diseases. Overall, this review aims to condense a comprehensive collection of high-yield, low-cost, and ecofriendly extraction methods for obtaining phlorotannins with remarkable antioxidant and antidiabetic capacities.
Effects of Modified Dietary Fiber from Fresh Corn Bracts on Obesity and Intestinal Microbiota in High-Fat-Diet Mice
Authors: Geng Ningning , Li Ying , Zhang Yan , Wang Hongjuan , Song Jiangfeng , Yu Lijun , Wu Caie
Published: June 2023

The effects of insoluble dietary fiber from fresh corn bracts modified by dynamic high-pressure micro-fluidization (DHPM) on the pathological characteristics of obesity, intestinal microflora distribution and production of short-chain fatty acids in high-fat-diet C57BL/6 mice were evaluated. The results show that the DHPM-modified dietary fiber from fresh corn bracts significantly reduces weight gain, insulin resistance and oxidative damage caused by a high-fat diet, and promotes the production of SCFAs, especially acetic acid, propionic acid and butyric acid. These modified dietary fibers also change the proportion of different types of bacteria in the intestinal microflora of mice, reduce the ratio of Firmicutes and Bacteroidota and promote the proliferation of Bifidobacteriales. Therefore, the DHPM-modified dietary fiber from fresh corn bracts can be used as a good intestinal microbiota regulator to promote intestinal health, thereby achieving the role of preventing and treating obesity.
The Finally Rewarding Search for A Cytotoxic Isosteviol Derivative
Authors: Heisig Julia , Heise Niels V. , Hoenke Sophie , Ströhl Dieter , Csuk René
Published: June 2023

Acid hydrolysis of stevioside resulted in a 63% yield of isosteviol (1), which served as a starting material for the preparation of numerous amides. These compounds were tested for cytotoxic activity, employing a panel of human tumor cell lines, and almost all amides were found to be non-cytotoxic. Only the combination of isosteviol, a (homo)-piperazinyl spacer and rhodamine B or rhodamine 101 unit proved to be particularly suitable. These spacered rhodamine conjugates exhibited cytotoxic activity in the sub-micromolar concentration range. In this regard, the homopiperazinyl-spacered derivatives were found to be better than those compounds with piperazinyl spacers, and rhodamine 101 conjugates were more cytotoxic than rhodamine B hybrids.
Integration of Hybridization Strategies in Pyridine–Urea Scaffolds for Novel Anticancer Agents: Design, Synthesis, and Mechanistic Insights
Authors: Godesi Sreenivasulu , Nada Hossam , Lee Joohan , Kang Joon-Hee , Kim Soo-Youl , Choi Yongseok , Lee Kyeong
Published: June 2023

Annually, millions of new cancer cases are reported, leading to millions of deaths worldwide. Among the newly reported cases, breast and colon cancers prevail as the most frequently detected variations. To effectively counteract this rapid increase, the development of innovative therapies is crucial. Small molecules possessing pyridine and urea moieties have been reported in many of the currently available anticancer agents, especially VEGFR2 inhibitors. With this in mind, a rational design approach was employed to create hybrid small molecules combining urea and pyridine. These synthesized compounds underwent in vitro testing against breast and colon cancer cell lines, revealing potent submicromolar anticancer activity. Compound 8a, specifically, exhibited an impressive GI50 value of 0.06 μM against the MCF7 cancer cell line, while compound 8h displayed the highest cytotoxic activity against the HCT116 cell line, with a GI50 of 0.33 ± 0.042 μM. Notably, compounds 8a, 8h, and 8i demonstrated excellent safety profiles when tested on normal cells. Molecular docking, dynamic studies, and free energy calculations were employed to validate the affinity of these compounds as VEGFR2 inhibitors.