bluuebunny/crossref_metadata_2025 huggingface dataset:
Physio-Biochemical Integrators and Transcriptome Analysis Reveal Nano-Elicitation Associated Response during Dendrocalamus asper (Schult. and Schult. F.) Backer ex K. Heyne Micropropagation
Authors: Kumari Anita , Joshi Shubham , Dar Aqib Iqbal , Joshi Rohit
Published: August 2023

Bamboos are perennial, arborescent, monocarpic and industrially important non-timber plants. They are important for various purposes, such as carbon sequestration, biodiversity support, construction, and food and fiber production. However, traditional vegetative propagation is insufficient for bamboo multiplication. Moreover, little is known about the mechanism of gold nanoparticles (AuNPs) in vitro proliferation and regulation of physiological and biochemical properties. In this study, we investigated the impacts of citrate and cetyltrimethylammonium bromide (CTAB) coated AuNPs on in vitro proliferation, photosynthetic pigment content and antioxidant potential of Dendrocalamus asper (Schult. and Schult. F.) Backer ex K. Heyne. Various morpho-physiological and biochemical parameters were differentially affected along the citrate- and CTAB-coated AuNPs concentration gradients (200–600 µM). In vitro shoot proliferation, photosynthetic pigment content and antioxidant activities were higher in D. asper grown on Murashige and Skoog medium supplemented with 2 mg·L−1 benzyladenine and 400 µM citrate-coated AuNPs than in those grown on Murashige and Skoog medium supplemented with 600 µM CTAB- coated AuNPs. Identification of genes regulating in vitro D. asper proliferation will help understand the molecular regulation of AuNPs-mediated elicitation for modulating various physiological and biochemical activities during micropropagation. Gene Ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway analyses identified differentially expressed genes associated with in vitro modulation of AuNPs-regulated biological processes and molecular functions. The findings of this study provide new insight into AuNPs-mediated elicitation of in vitro mass scale bamboo propagation.
Depression in South Korean Adolescents Captured by Text and Opinion Mining of Social Big Data
Authors: Song Juyoung , Song Tae-Min , Lee Sangho , Seo Dong-Chul
Published: August 2023

Depression in adolescence is recognized as an important social and public health issue that interferes with continued physical growth and increases the likelihood of other mental disorders. The goal of this study was to examine online documents posted by South Korean adolescents for 3 years through the text and opinion mining of collectable documents in order to capture their depression. The sample for this study was online text-based individual documents that contained depression-related words among adolescents, and these were collected from 215 social media websites in South Korea from 1 January 2012 to 31 December 2014. A sentiment lexicon was developed for adolescent depressive symptoms, and such sentiments were analyzed through opinion mining. The depressive symptoms in the present study were classified into nine categories as suggested by the Diagnostic and Statistical Manual for Mental Disorders, 5th Edition (DSM-5). The association analysis and decision tree analysis of data mining were used to build an efficient prediction model of adolescent depression. Opinion mining indicated that 15.5% were emotionally stable, 58.6% moderately stressed, and 25.9% highly distressed. Data mining revealed that the presence of depressed mood most of the day or nearly every day had the greatest effect on adolescents’ depression. Social big data analysis may serve as a viable option for developing a timely response system for emotionally susceptible adolescents. The present study represents one of the first attempts to investigate depression in South Korean adolescents using text and opinion mining from three years of online documents that originally amounted to approximately 3.1 billion documents.
UAE Women’s Knowledge and Attitudes towards Physical Activity during Pregnancy
Authors: AlBlooshi Sharifa , Hijazi Rafiq , Kennedy Lynne , Al Rajabi Ala
Published: August 2023

The benefits of being physically active during pregnancy are widely acknowledged. It is important for the prevention of chronic diseases and the promotion of good health for mothers and children. However, physical activity by women in the UAE is notoriously low and reduced further during pregnancy. The same can be said regarding research about the knowledge and understanding of the benefits and risks associated with exercise as a predictor of behavior. We aimed to assess knowledge and attitudes towards physical activity during pregnancy amongst Emirati women. A cross-sectional digital survey was designed to assess knowledge and attitudes and distributed to women, aged 18–40 years, using non-randomized, purposeful snowball sampling. A total of 1538 women were recruited. Most participants were aged 20–29 years (53.5%), were Emiratis (88.9%), and had no history of chronic disease (68.6%). The participants self-reported very low levels of PA (75.5%) and had a below-average level of knowledge overall (40.6 ± 20). Younger ages (p < 0.001), lower educational levels (p = 0.004), being employed (p = 0.014), and having a history of chronic disease (p = 0.016) were significantly associated with lower mean knowledge scores, while being married (p = 0.003) was significantly associated with higher scores. The participants also exhibited a positive attitude towards physical activity during pregnancy by selecting answers that they supported it. To encourage physical activity, women living in the UAE could benefit from clear advice about safe physical activity during pregnancy.
Immunomodulatory Effects of SGLT2 Inhibitors—Targeting Inflammation and Oxidative Stress in Aging
Authors: Schönberger Ema , Mihaljević Vjera , Steiner Kristina , Šarić Sandra , Kurevija Tomislav , Majnarić Ljiljana Trtica , Bilić Ćurčić Ines , Canecki-Varžić Silvija
Published: August 2023

Given that the increase in the aging population has grown into one of the largest public health issues, inflammation and oxidative stress, which are closely associated with the aging process, became a focus of recent research. Sodium-glucose co-transporter 2 (SGLT2) inhibitors, a group of drugs initially developed as oral antidiabetics, have shown many beneficial effects over time, including improvement in renal function and cardioprotective effects. It has been shown that SGLT2 inhibitors, as a drug class, have an immunomodulatory and antioxidative effect, affecting endothelial function as well as metabolic parameters. Therefore, it is not surprising that various studies have investigated the potential mechanisms of action of SGLT2 inhibitors in age-related diseases. The proposed mechanisms by which SGLT2 inhibitors can achieve their anti-inflammatory effects include influence on AMPK/SIRT1/PGC-1α signaling, various cytokines, and the NLRP3 inflammasome. The antioxidative effect is related to their action on mitochondria and their influence on the signaling pathways of transforming growth factor β and nuclear erythroid 2-related factor 2/antioxidant response element. Also, SGLT2 inhibitors achieve their anti-inflammatory and antioxidative effects by affecting metabolic parameters, such as uric acid reduction, stimulation of ketogenesis, reduction of body weight, lipolysis, and epicardial fat tissue. Finally, SGLT2 inhibitors display anti-atherosclerotic effects that modulate inflammatory reactions, potentially resulting in improvement in endothelial function. This narrative review offers a complete and comprehensive overview of the possible pathophysiologic mechanisms of the SGLT2 inhibitors involved in the aging process and development of age-related disease. However, in order to use SGLT2 inhibitor drugs as an anti-aging therapy, further basic and clinical research is needed to elucidate the potential effects and complex mechanisms they have on inflammation processes.
The Impact of Subjective Poverty on the Mental Health of the Elderly in China: The Mediating Role of Social Capital
Authors: Li Yanghan , Chen Tianyi , Li Quan , Jiang Linxiu
Published: August 2023

Reducing subjective poverty among the elderly is an important aspect of poverty governance and is a necessary part of implementing the healthy aging strategy in China. In both China and the majority of low- and middle-income countries, systematic research on the relationship between subjective poverty and the mental health of the elderly needs to be expanded. In this study, we aimed to examine how social capital, including bonding and bridging social capital, mediate the relationship between subjective poverty and mental health among the elderly in China. Relying on the 2018 Chinese Longitudinal Healthy Longevity Survey (CLHLS) data, we used ordered probit (oprobit) regression, propensity score matching (PSM), and instrumental variable (IV) regression to estimate the effects of subjective poverty on mental health. The results indicate that subjective poverty has a significant negative impact on the mental health of the elderly in China. More importantly, social capital, including bonding and bridging social capital, partially mediates the relationship between subjective poverty and mental health. We believe that, in the process of implementing the government’s healthy aging strategy in China, society and government should recognize the importance and value of subjective poverty governance for the elderly. In particular, the construction of a social relationship network that centers on bonding and bridging social capital could be instrumental in dealing with subjective poverty among the elderly and safeguarding their mental health and wellbeing.
One Cluster per Condition Is Not a Valid Design in Cluster-Randomized Trials. Comment on Wang et al. The Effect of Different Physical Exercise Programs on Physical Fitness among Preschool Children: A Cluster-Randomized Controlled Trial. Int. J. Environ. Res. Public Health 2023, 20, 4254
Authors: Jamshidi-Naeini Yasaman , Pena Armando , Siddique Abu Bakkar , Brown Andrew W. , Allison David B.
Published: August 2023

Wang et al. [...]
Regulation of Glycoprotein VI-Dependent Platelet Activation and Thrombus Formation by Heparan Sulfate Proteoglycan Perlecan
Authors: Provenzale Isabella , De Simone Ilaria , Gibbins Jonathan M. , Heemskerk Johan W. M. , van der Meijden Paola E. J. , Jones Chris I.
Published: August 2023

Proteoglycans form a heterogeneous family of proteins with covalently bound sulfated glycosaminoglycans. The extracellular matrix proteoglycan perlecan has been proposed to bind to the platelet- and megakaryocyte-specific receptor G6bB, co-regulating platelet glycoprotein VI (GPVI) signaling. The derived non-sulfate proteoglycan endorepellin was previously shown to enhance platelet adhesion via the collagen receptor, integrin α2β1. Here, we compared the roles of perlecan and other matrix proteoglycans in platelet responses and thrombus formation. We used multi-color flow cytometry to measure the degranulation and integrin αIIbβ3 activation of washed platelets in response to various proteoglycans and collagen-related peptide (CRP), the GPVI agonist. Perlecan, but not endorepellin, enhanced the CRP-induced activation of platelets in a time- and concentration-dependent manner. Similar to collagen, immobilized perlecan, but not other proteoglycans, supported static platelet adhesion and spreading. In-flowed whole-blood perlecan diminished shear-dependent platelet adhesion, while it enforced GPVI-dependent thrombus formation—to a larger extent than endorepellin—to induce more contracted aggregates of activated platelets. We concluded that the sulfated proteoglycan perlecan enhances GPVI-dependent platelet responses extending to thrombus formation, but it does so at the expense of reduced adhesion of platelets under flow.
The Impact of Metformin on Tumor-Infiltrated Immune Cells: Preclinical and Clinical Studies
Authors: Abdelmoneim Mohamed , Aboalela Mona Alhussein , Naoe Yoshinori , Matsumura Shigeru , Eissa Ibrahim Ragab , Bustos-Villalobos Itzel , Sibal Patricia Angela , Takido Yuhei , Kodera Yasuhiro , Kasuya Hideki
Published: August 2023

The tumor microenvironment (TME) plays a pivotal role in the fate of cancer cells, and tumor-infiltrating immune cells have emerged as key players in shaping this complex milieu. Cancer is one of the leading causes of death in the world. The most common standard treatments for cancer are surgery, radiation therapy, and chemotherapeutic drugs. In the last decade, immunotherapy has had a potential effect on the treatment of cancer patients with poor prognoses. One of the immune therapeutic targeted approaches that shows anticancer efficacy is a type 2 diabetes medication, metformin. Beyond its glycemic control properties, studies have revealed intriguing immunomodulatory properties of metformin. Meanwhile, several studies focus on the impact of metformin on tumor-infiltrating immune cells in various tumor models. In several tumor models, metformin can modulate tumor-infiltrated effector immune cells, CD8+, CD4+ T cells, and natural killer (NK) cells, as well as suppressor immune cells, T regulatory cells, tumor-associated macrophages (TAMs), and myeloid-derived suppressor cells (MDSCs). In this review, we discuss the role of metformin in modulating tumor-infiltrating immune cells in different preclinical models and clinical trials. Both preclinical and clinical studies suggest that metformin holds promise as adjunctive therapy in cancer treatment by modulating the immune response within the tumor microenvironment. Nonetheless, both the tumor type and the combined therapy have an impact on the specific targets of metformin in the TME. Further investigations are warranted to elucidate the precise mechanisms underlying the immunomodulatory effects of metformin and to optimize its clinical application in cancer patients.
Association between Human Leukocyte Antigen and End-Stage Renal Disease in Patients from Transylvania, Romania
Authors: Iancu Loga Luminita-Ioana , Dican Lucia , Chiorean Alin Dan , Chelaru Vlad Florin , Elec Florin Ioan , Catana Cristina Sorina , Marta Monica Mihaela , Lucaciu Roxana Liana , Hangan Adriana Corina , Bondor Cosmina Ioana , Vica Mihaela Laura , Matei Horea Vladi
Published: August 2023

End-stage renal disease (ESRD) is the final stage of chronic kidney disease. This study explored the association between human leukocyte antigen (HLA) and ESRD. The interaction between genetic and environmental factors may also play a role in the development of ESRD. The study included 2392 ESRD patients who were awaiting renal transplantation. Blood samples were genotyped by SSOP and SSP-PCR methods. Multivariate logistic regression analysis showed that HLA-A*11 (p = 0.027), HLA-A*34 (p = 0.017), HLA-A*69 (p = 0.012), HLA-B*41 (p < 0.001), HLA-B*50 (p = 0.004), HLA-DRB1*10 (p = 0.027), and HLA-DRB1*14 (p = 0.004) were positively associated with ESRD (OR > 1); HLA-DRB1*07 (p < 0.001), HLA-DRB1*08 (p = 0.005), and HLA-DRB1*13 (p < 0.001) were protective against ESRD (OR < 1); and the three-locus haplotype HLA-A*02–B*41–DRB1*03, containing one susceptible allele, was strongly associated with ESRD (p < 0.001, OR = 3.15). In conclusion, this retrospective analysis of HLA typing in patients with ESRD of various etiologies suggests that molecular data on the HLA polymorphism should be collected in order to identify high-risk ESRD patients and to improve graft survival after kidney transplantation.
Assessment of SDN Controllers in Wireless Environment Using a Multi-Criteria Technique
Authors: Koulouras Ioannis , Bobotsaris Ilias , Margariti Spiridoula V. , Stergiou Eleftherios , Stylios Chrysostomos
Published: August 2023

Software-defined network (SDN) technology can offer wireless networks the advantages of simplified control and network management. This SDN subdomain technology is called the software-defined wireless network (SDWN). In this study, the performance of four controllers in an SDWN environment is assessed, since the controller is the most significant component of the entire network. Using the Mininet-WiFi platform, the performance of each controller is evaluated in terms of throughput, latency, jitter, and packet loss. Moreover, a multi-criteria evaluation is introduced and applied to provide a fair comparison between SDWNs. This study provides an appropriate configuration of SDWNs that is useful for network engineering and can be used for SDWNs performance optimization.
A Subjective Logical Framework-Based Trust Model for Wormhole Attack Detection and Mitigation in Low-Power and Lossy (RPL) IoT-Networks
Authors: Javed Sarmad , Sajid Ahthasham , Kiren Tayybah , Khan Inam Ullah , Dewi Christine , Cauteruccio Francesco , Christanto Henoch Juli
Published: August 2023

The increasing use of wireless communication and IoT devices has raised concerns about security, particularly with regard to attacks on the Routing Protocol for Low-Power and Lossy Networks (RPL), such as the wormhole attack. In this study, the authors have used the trust concept called PCC-RPL (Parental Change Control RPL) over communicating nodes on IoT networks which prevents unsolicited parent changes by utilizing the trust concept. The aim of this study is to make the RPL protocol more secure by using a Subjective Logic Framework-based trust model to detect and mitigate a wormhole attack. The study evaluates the trust-based designed framework known as SLF-RPL (Subjective Logical Framework-Routing Protocol for Low-Power and Lossy Networks) over various key parameters, i.e., low energy consumption, packet loss ratio and attack detection rate. The achieved results were conducted using a Contiki OS-based Cooja Network simulator with 30, 60, and 90 nodes with respect to a 1:10 malicious node ratio and compared with the existing PCC-RPL protocol. The results show that the proposed SLF-RPL framework demonstrates higher efficiency (0.0504 J to 0.0728 J out of 1 J) than PCC-RPL (0.065 J to 0.0963 J out of 1 J) in terms of energy consumption at the node level, a decreased packet loss ratio of 16% at the node level, and an increased attack detection rate at network level from 0.42 to 0.55 in comparison with PCC-RPL.
Network Modeling for Post-Entry Management of Invasive Pest Species in the Philippines: The Case of the Colorado Potato Beetle, Leptinotarsa decemlineata (Say, 1824) (Coleoptera: Chrysomelidae)
Authors: Almarinez Billy Joel M. , Amalin Divina M. , Aviso Kathleen B. , Cabezas Heriberto , Lao Angelyn R. , Tan Raymond R.
Published: August 2023

Crop shifting is considered as an important strategy to secure future food supply in the face of climate change. However, use of this adaptation strategy needs to consider the risk posed by changes in the geographic range of pests that feed on selected crops. Failure to account for this threat can lead to disastrous results. Models can be used to give insights on how best to manage these risks. In this paper, the socioecological process graph technique is used to develop a network model of interactions among crops, invasive pests, and biological control agents. The model is applied to a prospective analysis of the potential entry of the Colorado potato beetle into the Philippines just as efforts are being made to scale up potato cultivation as a food security measure. The modeling scenarios indicate the existence of alternative viable pest control strategies based on the use of biological control agents. Insights drawn from the model can be used as the basis to ecologically engineer agricultural systems that are resistant to pests.
Almost Forgotten Research Contexts: William Stern’s Giftedness Research
Authors: Heinemann Rebecca
Published: August 2023

This article examines the concept of intelligence and giftedness of the German psychologist and philosopher William Stern, the leading intelligence and giftedness researcher in Germany from the early 20th century to 1933. Stern developed a multifactorial giftedness model that integrated empirical and philosophical perspectives and was thus far ahead of his time. This concept was not taken up for a long time—not least because of the break that the research on giftedness suffered in Germany in 1933—and has not yet been presented with the required complexity and interdisciplinarity. In the USA, Stern’s research has so far been reduced to the IQ formula he created. The author presents Stern’s concept of giftedness in the context of the particular scientific–historical and educational–political situation in Germany in the first third of the 20th century. The pedagogical conclusions that Stern associated with the research on giftedness, and which essentially referred to the requirement to support all gifted children, regardless of social class, are also illuminated.
Spatiotemporal Dynamics and Drivers of Wind Erosion during 1990–2020 in the Yarlung Zangbo River Basin, Southern Tibetan Plateau
Authors: Qin Xiaomin , Zhao Dongmei , Zhang Baojun , Xiong Donghong , Yuan Zhengrong , Zhang Wenduo , Liu Lin , Rai Dil Kumar , Laraib Sheikh , Deng Wei
Published: August 2023

Wind erosion is recognized as one of the main environmental issues and seriously threatens ecosystem services in the Yarlung Zangbo River basin (YZRB), southern Tibetan Plateau. Exploring the spatiotemporal dynamics and drivers of wind erosion is crucial for improving regional ecosystem services and sustainable development. This study was conducted to examine the spatiotemporal patterns of soil wind erosion modulus (SWEM) in YZRB from 1990 to 2020 by using the revised wind erosion equation (RWEQ) and to identify the influence of climate change and anthropogenic activities on wind erosion dynamics. The results showed that temporally, the overall SWEM presented a significant downward trend (−0.912 t·hm−2·a−1) and a continuous downward trend in the key implementation areas of ecological engineering. Spatially, the severe area of wind erosion is mainly concentrated in the flat and broad river valley, where sand sources are widely distributed. Significant SWEM differences were found among various land use/cover (LULC) types. Exceeding 90% reduction rates in SWEM occurred in forests, grasslands, and cultivated land. Additionally, the influence analysis showed that climate change was the dominant factor driving the variations in wind erosion due to the reduction of wind speed. By contrast, the contribution of anthropogenic activities is relatively less, accounting for 43.50% of wind erosion change, which closely matches the transfer of LULC to grassland and forest land with the implementation area of ecological engineering projects. This study provides useful information on the driving mechanism of wind erosion, prevention service changes, and determining priority zones for desertification prevention in YZRB. We suggest that eco-restoration activities should be endorsed in the future, as well as the adaptive management that is required to control wind erosion and improve ecosystem services and human well-being for people in the YZRB region.
Recovery of Pure Lead-Tin Alloy from Recycling Spent Lead-Acid Batteries
Authors: Malecha Daniel , Małecki Stanisław , Jarosz Piotr , Kowalik Remigiusz , Żabiński Piotr
Published: August 2023

Spent lead–acid batteries have become the primary raw material for global lead production. In the current lead refining process, the tin oxidizes to slag, making its recovery problematic and expensive. This paper aims to present an innovative method for the fire refining of lead, which enables the retention of tin contained in lead from recycled lead–acid batteries. The proposed method uses aluminium scrap to remove impurities from the lead, virtually leaving all of the tin in it. The results of the conducted experiments indicate the high efficiency of the proposed method, which obtained a pure Pb-Sn alloy. This alloy is an ideal base material for the production of battery grids. This research was carried out on an industrial scale, which confirms the possibility of facile implementation of the method in almost every lead–acid battery recycling plant in the world.
Efficient Reduction in Methylene Blue Using Palladium Nanoparticles Supported by Melamine-Based Polymer
Authors: Alkayal Nazeeha S. , Ibrahim Manal , Tashkandi Nada , Alotaibi Maha M.
Published: August 2023

In this work, palladium nanoparticles, supported by polyaminals (Pd@PAN-NA), were synthesized via a reverse double solvent approach and used as a nano catalyst. The thermogravimetric and the elemental analysis revealed that the catalyst had good dispersity and improved thermal stability. The catalytic activity of the prepared Pd@PAN-NA catalyst was studied for a methylene blue chemical reaction in the presence of NaBH4 as a reducing agent. The effect of the catalyst dose, pH, and dye initial concentration were examined to optimize the chemical reduction conditions. The prepared catalyst Pd@PAN-NA removed 99.8% of methylene blue organic dye, indicating its potential effect for treating waste and contaminated water.
Material Characterization of Polypropylene and Polystyrene Regarding Molecular Degradation Behavior
Authors: Schall Christoph , Schöppner Volker
Published: August 2023

During the processing of thermoplastics, polymers are subjected to high stress. As a result of this stress, the polymer chains break, leading to a lower molar mass. This further leads to a lower viscosity of the plastic melt and, eventually, to poorer mechanical properties of the manufactured plastic product. Especially in the context of recycling plastics, this poses a challenge to process technology and product properties. This work aims is to provide a prediction of the material degradation under known stress, so that, for example, a process design that is gentle on the material can be carried out. In order to be able to predict material degradation under a load, a test stand for defined material degradation was designed. The test stand allows for material damaging under a defined temperature, shear rate and residence time. At the same time, the test stand can be used to measure the viscosity, which is used to describe the degradation behavior, since the viscosity correlates with the molar mass. The measured decrease in viscosity under stress can be used to predict material damage under the influencing variables of temperature, shear rate and residence time by means of a test plan and a suitable mathematical description of the measured data. The mathematical description can thus be integrated into simulation environments for plastics processing, so that a simulation of the material degradation can be carried out, if necessary also taking the viscosity reduction into account.
Textronic Solutions Used to Produce Layers Sensitive to Chemical Stimuli—Gas Sensors: A Review
Authors: Skrzetuska Ewa , Szablewska Paulina
Published: August 2023

Thanks to the intensive development of textronics, textronic applications are already visible in many areas of everyday life. Many researchers around the world have focused on the invention of textronic systems to increase security, create technological innovations and make everyday life easier and more interesting. Due to the wide use of chemical textile sensors, this review article lists scientific publications covering all types of wearable chemical sensors along with their latest developments. The latest developments from the last few years in moisture, pH, sweat and biomolecules sensors are described. In this review, greatest emphasis and detail was placed on textile gas sensors and their production methods. The use of, among others, graphene and zinc oxide grown on cotton fabric, colorimetric textiles based on halochromic dye, electronic graphene fabric based on lotus fibers and graphene oxide and zinc oxide nanorods were considered. Finally, this article summarizes our current knowledge on gas sensors, compares the detection properties of the presented projects and indicates future directions of development.
Investigation of the Microstructure of Sintered Ti–Al–C Composite Powder Materials under High-Voltage Electrical Discharge
Authors: Kandrotaitė Janutienė Rasa , Mažeika Darius , Dlouhý Jaromír , Syzonenko Olha , Torpakov Andrii , Lipian Evgenii , Baltušnikas Arūnas
Published: August 2023

Dispersion-hardened materials based on TiC–AlnCn are alloys with high heat resistance, strength, and durability that can be used in aircraft and rocket technology as a hard lubricant. The titanium-rich composites of the Ti–Al–C system were synthesized via the spark plasma sintering process. Composite powder with 85% of Ti, 15% of Al, and MAX-phases was processed using high-voltage electrical discharge in kerosene at a specific energy of 25 MJ kg−1 to obtain nanosized particles. This method allows us to analyze the most efficient, energy saving, and less waste-generating technological processes producing materials with improved mechanical and physical properties. An Innova test indentation machine was used to determine the hardness of the synthesized composites. The microhardness of Ti–Al–C system samples was determined as approximately 500–600 HV. Scanning electron microscopy and energy-dispersive X-ray spectroscopy were performed to identify the hard titanium matrix reinforced by intermetallic phases and the clusters of carbides. Three types of reinforcing phases were detected existing in the composites—TiC, Al4C3, and Al3Ti, as well as a matrix consisting of α- and β-titanium. The lattice parameters of all phases detected in the composites were calculated using Rietveld analysis. It was determined that by increasing the temperature of sintering, the amount of aluminum and carbon increases in the carbides and intermetallic phases, while the amount of titanium decreases.
Evaluation of the Performance of Low-Cement Strain-Hardening Cementitious Composites Containing Desert Sand and Ground Scoria Rocks
Authors: Fares Galal , Khan Mohammad Iqbal
Published: August 2023

Fine aggregates are the main ingredients that control the success of the preparation and performance of strain-hardening cementitious composites (SHCCs). Worldwide deserts can be used as eternal sources of fine aggregates for the preparation of SHCCs. Arabian Peninsula desert sand spreads over the largest desert area in the world, covering an area of 2,300,000 km2 among the Arabian Gulf countries. White and dune desert sands were procured for use in this study. The morphological structure is important in selecting the appropriate sand for use in the preparation of SHCCs. The utilization of microfibers such as polyvinyl alcohol (PVA) has become common practice for the preparation of SHCCs. The presence of desert sand is proven to enhance the dispersibility of PVA due to its spherical structure, which alleviates the friction among the ingredients forming SHCCs. Two mechanisms are defined under the tensile force at the interface of microfibers and natural sand, namely, a strong frictional force leading to rupture or a weaker force causing pullout. The synergy between fibers and fine aggregate grains depends on their surface characteristics, which can be modified using different types of mineral admixtures. In this research, the alignment of microfibers as an indication of the quality of dispersion could be evaluated using a proposed approach based on an advanced technique of microstructural analysis. PVA dispersion and its relation to strain-hardening properties are visually correlated to the surface interaction of the mineral admixture and dune sand. The microdurability and cost effectiveness of SHCCs could be assessed using the proposed approach, as depicted by the results obtained in this research work.
Absorption Band Tunable La-Sr Co-Doped BaCo2-W Type Hexaferrites
Authors: Li Juan , Sun Xuetao
Published: August 2023

La-Sr co-doped Ba1−x(La0.5Sr0.5)xCo2Fe16O27 (x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0, respectively) hexaferrites were prepared by the solid-state method. W-type hexaferrite single phase structure with space group P63/mmc was obtained when the doping amount was x < 0.4 and an M-type hexaferrite and a spinel phase with smaller grains gradually replaced the W phase as the primary phases when x ≥ 0.6. The maximum Ms is 76.2 emu/g and the minimum Hc is 60 Oe at x = 0.4, as obtained by VSM analysis. The magnetoelectric properties of the samples were tested at 1–18 GHz with a vector network analyzer and the reflection loss was calculated based on transmission line theory. It was found that the introduction of an appropriate amount of La-Sr provides a large number of porosity defects while increasing the grain size, which can effectively improve the reflection of electromagnetic waves inside the material and dissipate more energy. At the same time, co-doping also makes the resonance frequency of the samples shift to lower frequency, resulting in tunable absorption properties in the C, X and Ku bands. When x = 0.2, the minimum reflection loss is −40.61 dB at 1.5 mm thickness, with the effective absorption bandwidth of 5.76 GHz in the X band; when x = 0.4, the minimum reflection loss is −37.45 dB at 2.5 mm, with the bandwidth of 4.97 GHz in the C band; when x = 0.6, the material has good absorption in both the X and Ku bands with the thickness less than 2 mm. The simple preparation method and good performance make La-Sr co-doped Co2W ferrite a promising microwave absorbing material.
Enhanced Mechanical Properties of QAl9-4 Aluminum Bronze for High-Speed-Rail Brake Systems with a Pulsed Magnetic Field
Authors: Hu Yujun , Zhao Hongjin , Zhang Yinghui , Zhang Bing , Hu Kefu
Published: August 2023

To improve the mechanical properties and wear resistance of QAl9-4 aluminum bronze alloy parts of high-speed rail brake calipers, the solid aluminum bronze alloy was treated with a pulsed magnetic field in which the magnetic induction intensity was 3T at room temperature. After that, a tensile test and a friction and wear test were carried out on the alloy. The results indicate that the magnetic field promotes the movement of low-angle grain boundaries less than 2° and splices to form subcrystals or fine crystals, which reduces the mean grain size of the alloy. The disordered dislocation changed into a locally ordered dislocation line, the dislocation distribution became uniform, and the dislocation density increased, which simultaneously improved the alloy’s tensile strength and elongation. The elongation increased by 10.2% compared with that without the magnetic field. The increase in strength can provide strong support for the wear-resistant hard phase, and the enhancement of plasticity can increase the alloy’s ability to absorb frictional vibration. Therefore, it was hard for cracks to form and extend, and the specimen’s average friction coefficient was reduced by 22.05%. The grinding crack width and depth decreased, the wear debris became more uniform and fine, and the alloy’s wear resistance increased.
The Influence of Alumina Bubbles on the Properties of Lightweight Corundum–Spinel Refractory
Authors: Xin Yalou , Jian Yunling , Yin Hongfeng , Tang Yun , Yuan Hudie , Liu Yuchi
Published: August 2023

The use of a lightweight corundum–spinel refractory in working lining could reduce the thermal conductivity of industrial furnaces. In this study, bubble alumina was introduced to realize a lightweight Al2O3-MgAl2O4 refractory assisted by the reactive sintering of Al2O3 and MgO. The effects of alumina bubble content and sintering temperature on the phase compositions, microstructure and properties of the lightweight refractory were investigated. The results indicated that the overall performance of the lightweight Al2O3-MgAl2O4 refractory was mainly dominated by the content of alumina bubbles. The bulk density, compressive strength and thermal conductivity all decreased when the alumina bubble content increased from 10 to 30 wt%. Meanwhile, the sintering temperature also significantly affected the properties of the obtained refractory. It is worth noting that specimens fired at 1650 °C achieved a high refractoriness under load (RUL) of more than 1700 °C when alumina bubble content was less than 30 wt%, which was comparable to that of the dense Al2O3-MgAl2O4 refractory. The thermal conductivity of the obtained samples was remarkably decreased to no more than 2.13 W/(m·K). In order to overcome the trade-off between the light weight of the refractory and overall performance, it is feasible to adjust the content of alumina bubbles and raise the sintering temperature appropriately.
Quenched Residual Stress Reduction in Pentagon-Curved Aluminum Alloy Forgings Using the Bulging Process
Authors: Luo Chuanwei , Li Chen , Zhang Xinquan , Wu Yunxin , Zhang Tao
Published: August 2023

Quenched residual stress in pentagon-curved forgings (PCGs) often leads to severe deformation during subsequent machining operations. This study aims to mitigate the quenched residual stress in PCGs through the implementation of the bulging method. The edge distance ratio (e/D), a geometric characteristic of PCGs, is defined and considered in the established thermo-mechanical model, which incorporates the effects of quenched residual stress. Increasing e/D resulted in amplified maximum internal stresses and surface stresses. To address this issue, a bulging finite element (FE) model was developed to effectively alleviate the quenched residual stress. The stress reduction in surface stress and internal stress was qualified using average stress reduction (Ra) and peak stress reduction (Rp), respectively. Notably, stress reduction exhibited an inverse relationship with e/D, indicating that decreasing e/D yields greater stress reduction. Furthermore, an overall stress reduction assessment was conducted for different bulging ratios, revealing that the stress reduction increased as the bulging ratio increased. A comprehensive comparison of different bulging ratios highlighted 2% as the most optimal bulging ratio for stress reduction in PCGs. X-ray diffraction measurement and the contour method were employed to determine surface stress and internal stress, respectively. The experimental results were in agreement with the simulation outcomes, validating the high accuracy of the FE model.
Mechanical Performance and Microstructural Characterization of Light Alloys
Authors: Huo Qinghuan
Published: August 2023

The present Special Issue titled “Mechanical Performance and Microstructural Characterization of Light Alloys” aims to report the close relation between mechanical performance and microstructure in light alloys, such as Al, Mg, Ti, and their alloys [...]
Structure, Conductivity, and Sensor Properties of Nanosized ZnO-In2O3 Composites: Influence of Synthesis Method
Authors: Ikim Mariya I. , Gromov Vladimir F. , Gerasimov Genrikh N. , Spiridonova Elena Y. , Erofeeva Anastasiya R. , Kurmangaleev Kairat S. , Polunin Kirill S. , Ilegbusi Olusegun J. , Trakhtenberg Leonid I.
Published: August 2023

The influence of the method used for synthesizing ZnO-In2O3 composites (nanopowder mixing, impregnation, and hydrothermal method) on the structure, conductivity, and sensor properties is investigated. With the nanopowder mixing, the size of the parent nanoparticles in the composite remains practically unchanged in the range of 50–100 nm. The impregnation composites consist of 70 nm In2O3 nanoparticles with ZnO nanoclusters < 30 nm in size located on its surface. The nanoparticles in the hydrothermal composites have a narrow size distribution in the range of 10–20 nm. The specific surface of hydrothermal samples is five times higher than that of impregnated samples. The sensor response of the impregnated composite to 1100 ppm H2 is 1.3–1.5 times higher than the response of the mixed composite. Additives of 15–20 and 85 wt.% ZnO to mixed and impregnated composites lead to an increase in the response compared with pure In2O3. In the case of hydrothermal composite, up to 20 wt.% ZnO addition leads to a decrease in response, but 65 wt.% ZnO addition increases response by almost two times compared with pure In2O3. The sensor activity of a hydrothermal composite depends on the phase composition of In2O3. The maximum efficiency is reached for the composite containing cubic In2O3 and the minimum for rhombohedral In2O3. An explanation is provided for the observed effects.
Application of Calcium Carbonate as a Controlled Release Carrier for Therapeutic Drugs
Authors: Li Siying , Lian Bin
Published: August 2023

A drug carrier usually refers to a tool that can carry the effective ingredients of drugs into the human body. The drug-controlled release system prepared by a new drug carrier can allow the gradual release of the drug in the human body at a stable rate, thus decreasing the frequency of administration and reducing the toxicity and side effects thereof; however, existing drug carriers generally have problems such as low drug loading, poor biocompatibility, stability, and specificity, each of which could be improved. Calcium carbonate can be used as a sustained-release carrier of active substances, with good biocompatibility, biodegradability, low cost, easy preparation, and broad application prospects. This paper reviews the synthesis and structural characteristics of calcium carbonate carrier materials and the related research progress of calcium carbonate as a controlled release carrier for therapeutic drugs, providing a reference for promoting the research and application of calcium carbonate as a drug carrier.
Digital Rock Physics in Cuttings Using High-Resolution Thin Section Scan Images
Authors: Caja Miguel Ángel , Castillo José Nicolás , Santos Carlos Alberto , Pérez-Jiménez José Luis , Fernández-Díaz Pedro Ramón , Blázquez Vanesa , Esteve Sergi , Campos José Rafael , Bover-Arnal Telm , Martín-Martín Juan Diego
Published: August 2023

Digital rock physics (DRP) has undergone significant advancements in the use of various imaging techniques to acquire three-dimensional volumes and images of rock samples for the computation of petrophysical properties. This study focuses on developing a DRP workflow using high-resolution thin section scans for computing porosity and permeability in cuttings samples. The workflow was tested on quarry sandstone plug samples and artificially generated pseudo-cuttings before applying it to real cuttings from oil and gas wells. The results show that the porosity and permeability values obtained through the DRP workflow are statistically equivalent to those obtained through conventional routine core analysis (RCAL). The workflow was also able to handle the presence of various lithologies in real cuttings samples. The study demonstrates the feasibility of obtaining porosity and permeability values in cutting samples using the DRP approach, offering a fast and cost-effective methodology that provides additional data and allows linking petrophysical properties to image data from the cuttings.
Development of Iron–Silicate Composites by Waste Glass and Iron or Steel Powders
Authors: Rada Roxana , Vermesan Horatiu , Rada Simona , Leostean Cristian , Manea Daniela Lucia , Culea Eugen
Published: August 2023

There is growing interest in the opportunities regarding construction and demolition wastes, such as glass and metal powders, for developing a circular economy and their transformation into new materials. This management and recycling of construction and demolition waste offers environmental benefits and conservation of natural resources. In this paper, new magnetic composite materials were prepared by wet chemical synthesis methods using crushed glasses and iron and steel waste powders as raw materials. The prepared iron–silicate composites were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis, infrared (IR), ultraviolet–visible, and electron paramagnetic resonance (EPR) spectroscopy, and magnetic measurements. The XRD data confirm the formation of varied crystalline phases of the iron ions. The presence of the Fe3O4 crystalline phase was detected in the composites containing the iron waste powders. The inspection of the SEM micrographs revealed slightly better homogeneity for the composite material containing larger amounts of iron waste and heterogeneous morphology with cracks and random crystallinity for the composite doped with steel waste. By doping with different contents of iron or steel waste powder, structural modifications in the silicate network and the formation of new bands in the IR spectra were evidenced. The UV-Vis spectra were characterized by the absorption peaks for both the tetrahedral and octahedral geometries of the Fe3+ ions and the octahedral coordination of the Fe2+ ions with oxygen anions. The EPR data show resonance lines with g ~2, 4.3, and 6.4, corresponding to the Fe3+ ions. Using hysteresis curves, the superparamagnetic properties of the iron–silicate composites were evidenced.
Endophytic Microbes from Medicinal Plants in Fenghuang Mountain as a Source of Antibiotics
Authors: Yang Aiping , Hong Yu , Zhou Fengjuan , Zhang Ling , Zhu Youjuan , Wang Chang , Hu Yang , Yu Li , Chen Lihong , Wang Xiachang
Published: August 2023

One of the largest concerns with world health today is still antibiotic resistance, which is making it imperative to find efficient alternatives as soon as possible. It has been demonstrated that microbes are reliable sources for the creation of therapeutic antibiotics. This research intends to investigate the endophytic microorganisms from several medicinal plants in Fenghuang Mountain (Jiangsu Province, China) and to discover new antibiotics from their secondary metabolites. A total of 269 endophytic strains were isolated from nine distinct medicinal plants. Taxonomic analysis revealed that there were 20 distinct species among these endophytes, with Streptomyces being the most common genus. Three of the target strains were chosen for scale-up fermentation after preliminary screening of antibacterial activities and the metabolomics investigation using LC-MS. These strains were Penicillium sp. NX-S-6, Streptomyces sp. YHLB-L-2 and Streptomyces sp. ZLBB-S-6. Twenty-three secondary metabolites (1–23), including a new sorbicillin analogue (1), were produced as a result of antibacterial activity-guided isolation. Through spectroscopic analysis using MS and NMR, the structures of yield compounds were clarified. According to antibacterial data, S. aureus or B. subtilis were inhibited to varying degrees by sorrentanone (3), emodic acid (8), GKK1032 B (10), linoleic acid (14), toyocamycin (17) and quinomycin A (21). The most effective antimicrobial agent against S. aureus, B. subtilis, E. coli and A. baumannii was quinomycin A (21). In addition, quinomycin A showed strong antifungal activity against Aspergillus fumigatus, Cryptococcus neoformans, and two clinical isolated strains Aspergillus fumigatus #176 and #339, with MIC as 16, 4, 16 and 16 µg/mL, respectively. This is the first time that bioprospecting of actinobacteria and their secondary metabolites from medicinal plants in Fenghuang Mountain was reported. The finding demonstrates the potential of endophytic microbes in medical plants to produce a variety of natural products. Endophytic microbes will be an important source for new antibiotics.
High-Dose Deltamethrin Induces Developmental Toxicity in Caenorhabditis elegans via IRE-1
Authors: Chen Chuhong , Deng Ying , Liu Linyan , Zou Zhenyan , Jin Chenzhong , Chen Zhiyin , Wang Shuanghui
Published: August 2023

Deltamethrin (DM), a Type II pyrethroid, is widely used worldwide in agriculture, household applications, and medicine. Recent studies have shown that DM exerts a variety of toxic effects on organs such as the kidney, heart muscle, and nerves in animals. However, little is known about the effects of high-dose DM on growth and development, and the mechanism of toxicity remains unclear. Using the Caenorhabditis elegans model, we found that high-dose DM caused a delay in nematode development. Our results showed that high-dose DM reduced the activation of the endoplasmic reticulum unfolded protein response (UPRER). Further studies revealed that high-dose DM-induced developmental toxicity and reduced capacity for UPRER activation were associated with the IRE-1/XBP-1 pathway. Our results provide new evidence for the developmental toxicity of DM and new insights into the mechanism of DM toxicity.