bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluating Novel Agarose-Based Buccal Gels Scaffold: Mucoadhesive and Pharmacokinetic Profiling in Healthy Volunteers
Authors: Syed Muhammad Ali , Aziz Ghiyyas , Jehangir Muhammad Bilal , Tabish Tanveer A. , Zahoor Ameer Fawad , Khalid Syed Haroon , Khan Ikram Ullah , Hosny Khaled Mohamed , Rizg Waleed Yousof , Hanif Sana , Arshad Rabia , Abdul Qayyum Muhammad , Irfan Muhammad
Published: August 2022

Agarose (AG) forms hydrocolloid in hot water and possesses a noteworthy gel strength. However, no reasonable scientific work on investigating the mucoadhesive character of AG has been reported. Therefore, the current study was designed to develop AG and carbopol (CP) based buccal gel scaffold for simultaneous release of benzocaine (BZN) and tibezonium iodide (TIB). Gels’ scaffold formulations (F1–F12) were prepared with varied concentrations (0.5–1.25% w/v) of AG and CP alone or their blends (AG-CP) using homogenization technique. The prepared formulations were characterized for solid-state, physicochemical, in vitro, ex vivo, and in vivo mucoadhesive studies in healthy volunteers. The results showed that mucoadhesive property of AG was concentration dependent but improved by incorporating CP in the scaffolds. The ex vivo mucoadhesive time reached >36 h when AG was used alone or blended with CP at 1% w/v concentration or above. The optimized formulation (F10) depicted >98% drugs release within 8 h and was also storage stable up to six months. The salivary concentration of BZN and TIB from formulation F10 yielded a Cmax value of 9.97 and 8.69 µg/mL at 2 and 6 h (tmax), respectively. In addition, the FTIR, PXRD, and DSC results confirmed the presence of no unwanted interaction among the ingredients. Importantly, the mucoadhesive study performed on healthy volunteers did not provoke any signs of inflammation, pain, or swelling. Clearly, it was found from the results that AG-CP scaffold provided better mucoadhesive properties in comparison to pure AG or CP. Conclusively, the developed AG based mucoadhesive drug delivery system could be considered a potential alternative for delivering drugs through the mucoadhesive buccal route.
A Comparative Study of Quercetin-Loaded Nanocochleates and Liposomes: Formulation, Characterization, Assessment of Degradation and In Vitro Anticancer Potential
Authors: Munot Neha , Kandekar Ujjwala , Giram Prabhanjan S. , Khot Kavita , Patil Abhinandan , Cavalu Simona
Published: August 2022

Quercetin, a flavonoid, has antioxidant and anti-inflammatory properties and the potential to inhibit the proliferation of cancer, but its therapeutic efficacy is lowered due to poor solubility and bioavailability. Quercetin-loaded nanocochleates (QN) were developed using a trapping method by the addition of calcium ions into preformed negatively charged liposomes (QL) prepared by a thin-film hydration method. Liposomes were optimized by varying the concentration of Dimyristoyl phosphatidyl glycerol and quercetin by applying D-optimal factorial design using Design-Expert® software. Stable rods were observed using TEM with an average particle size, zeta potential and encapsulation efficiency of 502 nm, −18.52 mV and 88.62%, respectively, for QN which were developed from spherical QL showing 111.06 nm, −40.33 mV and 74.2%, respectively. In vitro release of quercetin from QN and QL was extended to 24 h. Poor bioavailability of quercetin is due to its degradation in the liver, so to mimic in vivo conditions, the degradation of quercetin released from QL and QN was studied in the presence of rat liver homogenate (S9G) and results revealed that QN, due to its unique structure, i.e., series of rolled up solid layers, shielded quercetin from the external environment and protected it. The safety and biocompatibility of QL and QN were provenby performing cytotoxicity studies on fibroblast L929 cell lines. QN showed superior anticancer activity compared to QL, as seen for human mouth cancerKB cell lines. Stability studies proved that nanocochleates were more stable than liposomal formulations. Thus, nanocochleates might serve as pharmaceutical nanocarriers for the improved efficacy of drugs with low aqueous solubility, poor bioavailability, poor targeting ability and stability.
Optical System Design of Oblique Airborne-Mapping Camera with Focusing Function
Authors: Zhang Hongwei , Chen Weining , Ding Yalin , Qu Rui , Chang Sansan
Published: August 2022

The use of airborne-mapping technology plays a key role in the acquisition of large-scale basic geographic data information, especially in various important civil/military-mapping missions. However, most airborne-mapping cameras are limited by parameters, such as the flight altitude, working-environment temperature, and so on. To solve this problem, in this paper, we designed a panchromatic wide-spectrum optical system with a focusing function. Based on the catadioptric optical structure, the optical system approached a telecentric optical structure. Sharp images at different object distances could be acquired by micro-moving the focusing lens. At the same time, an optical passive compensation method was adopted to realize an athermalization design in the range of −40–60 °C. According to the design parameters of the optical system, we analyzed the influence of system focusing on mapping accuracy during the focusing process of the airborne-mapping camera. In the laboratory, the camera calibration and imaging experiments were performed at different focusing positions. The results show that the experimental data are consistent with the analysis results. Due to the limited experiment conditions, only a single flight experiment was performed. The results show that the airborne-mapping camera can achieve 1:5000 scale-imaging accuracy. Flight experiments for different flight altitudes are being planned, and the relevant experimental data will be released in the future. In conclusion, the airborne-mapping camera is expected to be applied in various high-precision scale-mapping fields.
Sugarcane Genotypes with Contrasting Biological Nitrogen Fixation Efficiencies Differentially Modulate Nitrogen Metabolism, Auxin Signaling, and Microorganism Perception Pathways
Authors: Carvalho Thais Louise G. , Rosman Aline C. , Grativol Clícia , de M. Nogueira Eduardo , Baldani José Ivo , Hemerly Adriana S.
Published: August 2022

Sugarcane is an economically important crop that is used for the production of fuel ethanol. Diazotrophic bacteria have been isolated from sugarcane tissues, without causing visible plant anatomical changes or disease symptoms. These bacteria can be beneficial to the plant by promoting root growth and an increase in plant yield. Different rates of Biological Nitrogen Fixation (BNF) were observed in different genotypes. The aim of this work was to conduct a comprehensive molecular and physiological analysis of two model genotypes for contrasting BNF efficiency in order to unravel plant genes that are differentially regulated during a natural association with diazotrophic bacteria. A next-generation sequencing of RNA samples from the genotypes SP70-1143 (high-BNF) and Chunee (low-BNF) was performed. A differential transcriptome analysis showed that several pathways were differentially regulated among the two BNF-contrasting genotypes, including nitrogen metabolism, hormone regulation and bacteria recognition. Physiological analyses, such as nitrogenase and GS activity quantification, bacterial colonization, auxin response and root architecture evaluation, supported the transcriptome expression analyses. The differences observed between the genotypes may explain, at least in part, the differences in BNF contributions. Some of the identified genes might be involved in key regulatory processes for a beneficial association and could be further used as tools for obtaining more efficient BNF genotypes.
Short-Term CO2 Treatment of Harvested Grapes (Vitis vinifera L., cv. Trebbiano) before Partial Dehydration Affects Berry Secondary Metabolism and the Aromatic Profile of the Resulting Wine
Authors: Santin Marco , Brizzolara Stefano , Castagna Antonella , Ranieri Annamaria , Tonutti Pietro
Published: August 2022

High CO2 concentrations applied to harvested horticultural products can modify primary and secondary metabolism. This work reports the metabolic responses to short-term CO2 treatments of white-skinned grapes (cv Trebbiano) undergoing postharvest partial dehydration. The influence of CO2 treatments on the aroma profile of the derived sweet wine was also assessed. Harvested grapes were treated with gaseous CO2 (30%) or air (control) for 24 h and then dehydrated (about 45% of weight loss) before vinification. Lipophilic and phenolic compounds of grape skin and the wine aroma profile were analyzed. In CO2-treated berries, the lipophilic and phenolic compounds decreased at a reduced and faster rate, respectively, during dehydration. Aroma profile of wine from CO2-treated grapes showed a slight but significantly higher content of glycosylated C13 and terpene compounds, and a decrease/absence of free acids, vanillin derivates and other phenol volatiles. The higher content of volatile alcohols in wine from treated berries suggests that the alcoholic fermentation was triggered. CO2 application before the withering process of Trebbiano grapes affects the aroma profile of the resulting wine by altering the free:glycosylated volatiles ratio. This study provides information on the possible use of CO2 as metabolic elicitor to modulate the aroma profile of the resulting wines obtained after grape dehydration.
The Role of Sulfur in Agronomic Biofortification with Essential Micronutrients
Authors: Chorianopoulou Styliani N. , Bouranis Dimitris L.
Published: August 2022

Sulfur (S) is an essential macronutrient for plants, being necessary for their growth and metabolism and exhibiting diverse roles throughout their life cycles. Inside the plant body, S is present either in one of its inorganic forms or incorporated in an organic compound. Moreover, organic S compounds may contain S in its reduced or oxidized form. Among others, S plays roles in maintaining the homeostasis of essential micronutrients, e.g., iron (Fe), copper (Cu), zinc (Zn), and manganese (Mn). One of the most well-known connections is homeostasis between S and Fe, mainly in terms of the role of S in uptake, transportation, and distribution of Fe, as well as the functional interactions of S with Fe in the Fe-S clusters. This review reports the available information describing the connections between the homeostasis of S and Fe, Cu, Zn, and Mn in plants. The roles of S- or sulfur-derived organic ligands in metal uptake and translocation within the plant are highlighted. Moreover, the roles of these micronutrients in S homeostasis are also discussed.
Synergistic Practicing of Rhizobacteria and Silicon Improve Salt Tolerance: Implications from Boosted Oxidative Metabolism, Nutrient Uptake, Growth and Grain Yield in Mung Bean
Authors: Mahmood Sajid , Daur Ihsanullah , Yasir Muhammad , Waqas Muhammad , Hirt Heribert
Published: August 2022

Plant growth promoting rhizobacteria (PGPR) and silicon (Si) are known for alleviating abiotic stresses in crop plants. In this study, Bacillus drentensis and Enterobacter cloacae strains of PGPR and foliar application of Si were tested for regulating the antioxidant metabolism and nutrient uptake on grain yield of mung bean under irrigation of saline water (3.12 and 7.81 dS m−1). Bacterial inoculation and supplemental Si (1 and 2 kg ha−1) reduced salinity-induced oxidative stress in mung bean leaves. The improved salt stress tolerance was achieved by enhancing the activities of catalase (45%), peroxidase (43%) and ascorbate peroxidase (48%), while decreasing malondialdehyde levels (57%). Enhanced nutrient uptake of magnesium 1.85 mg g−1, iron 7 mg kg−1, zinc 49.66 mg kg−1 and copper 12.92 mg kg−1 in mung bean seeds was observed with foliar application of Si and PGPR inoculation. Biomass (7.75 t ha−1), number of pods per plant (16.02) and 1000 seed weight (60.95 g) of plants treated with 2 kg Si ha−1 and B. drentensis clearly outperformed treatments with Si or PGPR alone. In conclusion, application of Si and PGPR enhances mung bean productivity under saline conditions, thereby helping exploitation of agriculture in low productive areas.
Investigation of Morinda citrifolia Activities through Pinoresinol and α-EG Related Gene Expression
Authors: Sudmoon Runglawan , Kaewdaungdee Sanit , Ameamsri Unchaleeporn , Tanee Tawatchai , Siripiyasing Pornnarong , Wonok Warin , Chaveerach Arunrat
Published: August 2022

α-EG is a unique substance that was first found in the leaves and fruits of Morinda citrifolia (Mc) growing in Thailand using GC-MS at 52.33% and 54.12%. It was then concentrated and its abundance quantified, along with that of pinoresinol, via GC, compared to the standards in leaves, ufp, rfp, rawfs, and seeds. α-EG and pinoresinol, which have collagen stimulating, skin whitening, and an inhibitory effect on wrinkle formation, were found in different concentrations and amounts. Three different concentrations of the five Mc part extracts were tested on NHDF for gene expression related to the aforementioned activities, COL1A1, COL1A2, and COL3A1, FGF1 and FGF7 by qRT-PCR. The results showed various expression levels, both stimulatory and inhibitory, with different concentrations of plant parts and genes. Similar results were revealed when the experiments were performed with Morus alba (Ma), which was found to contain 20.48 g protein p/100 g leaves at concentrations of 3.11 mg/mL. The studied Mc parts seem to have advantages based on the stated objectives, gene type and level of activity of each plant part. Rawfs and leaves supplemented with Ma samples were selected for toxicity tests with PBMCs. The lack of both cell and DNA toxicity from the rawfs indicated that they can be used safely.
Distinct Hormone Signalling-Modulation Activities Characterize Two Maize Endosperm-Specific Type-A Response Regulators
Authors: Royo Joaquín , Muñiz Luís M. , Gómez Elisa , Añazco-Guenkova Ana M. , Hueros Gregorio
Published: August 2022

ZmTCRR1 and 2 are type-A response regulators expressed in the maize endosperm transfer cells (TC). While type-B response regulators transcriptionally control canonical type-A response regulators, as part of the cytokinin signal transduction mechanism, the ZmTCRRs are regulated by ZmMRP1, a master regulator of TC identity. In addition, the corresponding proteins are not detected in the TC, accumulating in the inner endosperm cells instead. These features suggest these molecules are not involved in classical, cell-autonomous, cytokinin signalling pathways. Using transgenic Arabidopsis plants ectopically expressing these genes, we have shown that ZmTCRR1 and 2 can modulate auxin and cytokinin signalling, respectively. In Arabidopsis, the ectopic expression of ZmTCRR2 blocked, almost completely, cytokinin perception. Given the conservation of these signalling pathways at the molecular level, our results suggest that the ZmTCRRs modulate cytokinin and auxin perception in the inner endosperm cells.
Calluna vulgaris as a Valuable Source of Bioactive Compounds: Exploring Its Phytochemical Profile, Biological Activities and Apitherapeutic Potential
Authors: Cucu Alexandra-Antonia , Baci Gabriela-Maria , Cucu Alexandru-Bogdan , Dezsi Ştefan , Lujerdean Cristian , Hegeduş Iuliana Cristina , Bobiş Otilia , Moise Adela Ramona , Dezmirean Daniel Severus
Published: August 2022

Calluna vulgaris, belonging to the Ericaceae family, is an invasive plant that has widely spread from Europe all across Asia, North America, Australia and New Zealand. Being able to survive in rigid soil and environmental conditions, it is nowadays considered to be of high nature-conservation value. Known for its nutritional and medicinal properties, C. vulgaris stands out for its varied physiochemical composition, spotlighting a wide range of biological activity. Among the most important bioactive compounds identified in C. vulgaris, the phenolic components found in different parts of this herbaceous plant are the main source of its diverse pro-health properties (antioxidant, anti-inflammatory, antimicrobial, chemoprotective, etc.). Nonetheless, this plant exhibits an excellent nectariferous potential for social insects such as honeybees; therefore, comparing the bioactive compounds observed in the plant and in the final product of the beehive, namely honey, will help us understand and find new insights into the health benefits provided by the consumption of C. vulgaris-related products. Thus, the main interest of this work is to review the nutritional profile, chemical composition and biological activities of the C. vulgaris plant and its related honey in order to encourage the future exploration and use of this health-promoting plant in novel foods, pharmacological products and apitherapy.
Analysis of Tissue-Specific Defense Responses to Sclerotinia sclerotiorum in Brassica napus
Authors: Liu Jie , Zuo Rong , He Yizhou , Zhou Cong , Yang Lingli , Gill Rafaqat Ali , Bai Zetao , Zhang Xiong , Liu Yueying , Cheng Xiaohui , Huang Junyan
Published: August 2022

Sclerotinia stem rot (SSR) caused by Sclerotinia sclerotiorum (S. sclerotiorum) is the main disease threat of oilseed rape (Brassica napus), resulting in huge economic losses every year. SSR resistance manifests as quantitative disease resistance (QDR), and no gene with complete SSR resistance has been cloned or reported so far. Transcriptome analysis has revealed a large number of defense-related genes and response processes. However, the similarities and differences in the defense responses of different tissues are rarely reported. In this study, we analyzed the similarities and differences of different tissues in response to S. sclerotiorum at 24 h post inoculation (hpi) by using the published transcriptome data for respective leaf and stem inoculation. At 24 hpi, large differences in gene expression exist in leaf and stem, and there are more differentially expressed genes and larger expression differences in leaf. The leaf is more sensitive to S. sclerotiorum and shows a stronger response than stem. Different defense responses appear in the leaf and stem, and the biosynthesis of lignin, callose, lectin, chitinase, PGIP, and PR protein is activated in leaf. In the stem, lipid metabolism-mediated defense responses are obviously enhanced. For the common defense responses in both leaf and stem, the chain reactions resulting from signal transduction and biological process take the primary responsibility. This research will be beneficial to exploit the potential of different tissues in plant defense and find higher resistance levels of genotypic variability in different environments. Our results are significant in the identification of resistance genes and analysis of defense mechanisms.
The Use of the Thiol-Ene Addition Click Reaction in the Chemistry of Organosilicon Compounds: An Alternative or a Supplement to the Classical Hydrosilylation?
Authors: Krizhanovskiy Ilya , Temnikov Maxim , Kononevich Yuriy , Anisimov Anton , Drozdov Fedor , Muzafarov Aziz
Published: August 2022

This review presents the main achievements in the use of the thiol-ene reaction in the chemistry of silicones. Works are considered, starting from monomers and ending with materials.The main advantages and disadvantages of this reaction are demonstrated using various examples. A critical analysis of the use of this reaction is made in comparison with the hydrosilylation reaction.
Effects of Fiber Volume Fraction and Length on the Mechanical Properties of Milled Glass Fiber/Polyurea Composites
Authors: Qiao Jing , Zhang Quan , Wu Chong , Wu Gaohui , Li Longqiu
Published: August 2022

Composites of polyurea (PU) reinforced with milled glass fiber (MGf) were fabricated. The volume fraction and length of the milled glass fiber were varied to study their effects on the morphological and mechanical properties of the MGf/PU composites. The morphological attributes were characterized with scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. The SEM investigations revealed a uniform distribution and arbitrary orientation of milled glass fiber in the polyurea matrix. Moreover, it seems that the composites with longer fiber exhibit better interfacial bonding. It was found from the FTIR studies that the incorporation of milled glass fiber into polyurea leads to more phase mixing and decreases the hydrogen bonding of the polyurea matrix, while having a negligible effect on the H-bond strength. The compression tests at different strain rates (0.001, 0.01, 0.1, 1, 2000 and 3000 s−1) and dynamic mechanical properties over the temperature range from −30 to 100 °C at 1 Hz were performed. Experimental results show that the compressive behavior of MGf/PU composites is nonlinear and strain-rate-dependent. Both elastic modulus and flow stress at any given strain increased with strain rate. The composites with higher fiber volume fraction and longer fiber length are more sensitive to strain rate. Furthermore, the elastic modulus, stress at 65% strain and energy absorption capability were studied, taking into account both the effect of fiber volume fraction and mean fiber length. It is noted that an increase in fiber volume fraction and fiber length leads to an increase in elastic modulus, stress at 65% strain and absorbed energy up to ~103%, 83.0% and 137.5%, respectively. The storage and loss moduli of the composites also increase with fiber volume fraction and fiber length. It can be concluded that the addition of milled glass fiber into polyurea not only improves the stiffness of the composites but also increases their energy dissipative capability.
Numerical Simulation and Experimental Study the Effects of Process Parameters on Filament Morphology and Mechanical Properties of FDM 3D Printed PLA/GNPs Nanocomposite
Authors: Lei Mingju , Wei Qinghua , Li Mingyang , Zhang Juan , Yang Rongbin , Wang Yanen
Published: August 2022

The selection of optimal process parameters has a decisive effect on the quality of 3D printing. In this work, the numerical and experimental methods were employed to investigate the FDM printing deposition process of PLA/GNPs nanocomposite. The effect of process parameters on cross-sectional morphology and dimension of the deposited filament, as well as the mechanical property of the FDM printed specimens were studied. The extrusion and the deposition process of the molten PLA/GNPs nanocomposite was simulated as a fluid flow by the paradigm of CFD, the effects of printing temperature and shear rate on thermal-physical properties, such as viscosity and surface tension, were considered in models. Under the assumptions of non-Newtonian fluid and creep laminar flow, the deposition flow was controlled by two key parameters: the nozzle temperature and the nozzle velocity. The numerical model was verified by experiments from four aspects of thickness, width, area, and compactness of the deposited PLA/GNPs nanocomposite filament cross-section. Both the numerical simulation and experiment results show that with the increase of nozzle temperature and nozzle velocity, the thickness, area, and compactness of the deposited filament decreases. While the width of deposited filament increased with the increase of nozzle temperature and decrease of nozzle velocity. The decrease in thickness and the increase in width caused by the change of process parameters reached 10.5% and 24.7%, respectively. The tensile strength of the printed PLA/GNPs specimen was about 61.8 MPa under the higher nozzle temperatures and velocity condition, an improvement of 18.6% compared to specimen with the tensile strength of 52.1 MPa under the lower nozzle temperatures and velocity condition. In addition, the experimental results indicated that under the low nozzle velocity and nozzle temperature condition, dimensional standard deviation of the printed specimens decreased by 52.2%, 62.7%, and 68.3% in X, Y, and Z direction, respectively.
Construction and Evaluation of Small-Diameter Bioartificial Arteries Based on a Combined-Mold Technology
Authors: Jiao Weijie , Liu Chen , Shan Jingxin , Kong Zhiyuan , Wang Xiaohong
Published: August 2022

Arterial stenosis or blockage is the leading cause of cardiovascular disease, and the common solution is to substitute the arteries by autologous veins or bypass the blood vessels physically. With the development of science and technology, arteries with diameter larger than 6 mm can be substituted by unbiodegradable polymers, such as polytetrafluoroethylene, clinically. Nevertheless, the construction of a small-diameter (less than 6 mm) artery with living cells has always been a thorny problem. In this study, a suit of combined mold was designed and forged for constructing small-diameter arterial vessels. Based on this combined mold, bioactive arterial vessels containing adipose-derived stem cells (ASCs) and different growth factors (GFs) were assembled together to mimic the inner and middle layers of the natural arteries. Before assembling, ASCs and GFs were loaded into a gelatin/alginate hydrogel. To enhance the mechanical property of the bilayer arterial vessels, polylactic–glycolic acid (PLGA) was applied on the surface of the bilayer vessels to form the outer third layer. The biocompatibility, morphology and mechanical property of the constructed triple-layer arterial vessels were characterized. The morphological results manifested that cells grow well in the gelatin/alginate hydrogels, and ASCs were differentiated into endothelial cells (ECs) and smooth muscle cells (SMCs), respectively. In addition, under the action of shear stress produced by the flow of the culture medium, cells in the hydrogels with high density were connected to each other, similar to the natural vascular endothelial tissues (i.e., endothelia). Especially, the mechanical property of the triple-layer arterial vessels can well meet the anti-stress requirements as human blood vessels. In a word, a small-diameter arterial vessel was successfully constructed through the combined mold and has a promising application prospect as a clinical small-diameter vessel graft.
Advancements and Applications in the Composites of Silk Fibroin and Graphene-Based Materials
Authors: Xu Zhimin , Ma Yujie , Dai Huanyan , Tan Shuang , Han Bing
Published: August 2022

Silk fibroin and three kinds of graphene-based materials (graphene, graphene oxide, and reduced graphene oxide) have been widely investigated in biomedical fields. Recently, the hybrid composites of silk fibroin and graphene-based materials have attracted much attention owing to their combined advantages, i.e., presenting outstanding biocompatibility, mechanical properties, and excellent electrical conductivity. However, maintaining bio-toxicity and biodegradability at a proper level remains a challenge for other applications. This report describes the first attempt to summarize the hybrid composites’ preparation methods, properties, and applications to the best of our knowledge. We strongly believe that this review will open new doors for coming researchers.
Influence of Pre-Pressing Ring on the Weld Quality of Ultrasonically Welded Short Carbon Fiber Reinforced Nylon 6 Composite
Authors: Tian Zengguo , Zhi Qian , Zhang Guopeng , Tan Xinrong , Lu Lei , Wang Peichung , Liu Zhongxia
Published: August 2022

The ultrasonic welding (UW) technique is a fast-joining process; it is very suitable for the carbon fiber reinforced thermoplastic (CFRTP) composite. For improving the consistency of the welded joint quality, a new pre-pressing ring clamp (PPRC) was designed for ultrasonic welding carbon fiber reinforced nylon composites in this paper. The effects of the PPRC on the weld quality of the ultrasonic welding welded 4.0 mm thick 30% mass short carbon fiber reinforced Nylon 6 composite was investigated and compared with that of normal clamp weld joint. The weld strength, microstructure, and temperature evolution of the joint were analyzed by tensile test, scanning electron microscope, and temperature measurement. The results showed that the PPCR UW joints had larger central weld nugget size (478 mm2 vs. 300 mm2), thicker stable fusion region thickness (1.10 mm vs. 0.96 mm), resulting in a higher joint strength (6.86 kN vs. 6.21 kN) compared with the normal clamp UW joints under the same welding parameters. The real-time monitor curve of the horn displacement and temperature at the faying interface showed that the PPRC increased the heat rating at the faying interface during instable melting stage. The PPRC could improve the contact condition between workpieces and the utilization efficiency of ultrasonic energy, which boosted the melting rate of materials at faying interface and consequently the formation of a sound joint with enough weld size (i.e., 433 mm2) in a shorter welding time (i.e., 1.3 s). Therefore, the flexibility of component assembly would be increased by the use of this sort of clamps.
Effects of Different Concentrations of Arsine on the Synthesis and Final Properties of Polypropylene
Authors: Hernández-Fernández Joaquín , Guerra Yoleima , Puello-Polo Esneyder , Marquez Edgar
Published: August 2022

This article studies the effects of arsine on the synthesis and thermal degradation of 4 samples of virgin polypropylene (PP-virgin) and proposes reaction mechanisms that allow understanding of its behaviour. Different points are monitored during the polypropylene synthesis to perform TGA, DSC, FT-IR, RDX, and MFI analyses later. The content of AsH3 in polypropylene varies between 0.05 and 4.73 ppm, and of arsenic in virgin PP residues between 0.001 and 4.32 ppm for PP0 and PP10, increasing in fluidity index from 3.0 to 24.51. The origin of thermo-oxidative degradation is explained by the reaction mechanisms of the Molecule AsH3 with the active titanium center of the ZN catalyst and the subsequent oxidation to form radical complexes. OO-AsH-TiCl4-MgCl2 and (OO-as-OO)2 -TiCl4-MgCl2, which, by radical reactions, give rise to the formation of functional groups aldehyde, ketone, alcohol, carboxylic acid, CO, CO2, PP-Polyol, PP-Polyether, and PP-Isopropylethers. These species caused the TG and DTG curves to increase degradation peaks in pp samples.
Alkalization of Kraft Pulps from Pine and Eucalyptus and Its Effect on Enzymatic Saccharification and Viscosity Control of Cellulose
Authors: Carrillo-Varela Isabel , Vidal Claudia , Vidaurre Sebastián , Parra Carolina , Machuca Ángela , Briones Rodrigo , Mendonça Regis Teixeira
Published: August 2022

Bleached kraft pulps from eucalyptus and pine were subjected to cold caustic extraction (CCE) with NaOH (5, 10, 17.5, and 35%) for hemicelluloses removal and to increase cellulose accessibility. The effect of these changes was evaluated in enzymatic saccharification with the multicomponent Cellic CTec3 enzyme cocktail, and in viscosity reduction of pulps with the monocomponent Trichoderma reesei endoglucanase (EG). After CCE with 10% NaOH (CCE10) and 17.5% NaOH (CCE17.5), hemicellulose content lower than 1% was achieved in eucalyptus and pine pulps, respectively. At these concentrations, cellulose I started to be converted into cellulose II. NaOH concentrations higher than 17.5% decreased the intrinsic viscosity (from 730 to 420 mL/g in eucalyptus and from 510 to 410 mL/g in pine). Cellulose crystallinity was reduced from 60% to 44% in eucalyptus and from 71% to 44% in pine, as the NaOH concentration increased. Enzymatic multicomponent saccharification showed higher glucose yields in all CCE-treated eucalyptus samples (up to 93%) while only CCE17.5 and CCE35 pine pulps achieved 90% after 40 h of incubation. Untreated bleached pulps of both species presented saccharification yields lower than 70%. When monocomponent EG was used to treat the same pulps, depending on enzyme charge and incubation time, a wide range of intrinsic viscosity reduction was obtained (up to 74%). Results showed that eucalyptus pulps are more accessible and easier to hydrolyze by enzymes than pine pulps and that the conversion of cellulose I to cellulose II hydrate only has the effect of increasing saccharification of CCE pine samples. Viscosity reduction of CCE pulps and EG treated pulps were obtained in a wide range indicating that pulps presented characteristics suitable for cellulose derivatives production.
Current Prospects for Plastic Waste Treatment
Authors: Damayanti Damayanti , Saputri Desi Riana , Marpaung David Septian Sumanto , Yusupandi Fauzi , Sanjaya Andri , Simbolon Yusril Mahendra , Asmarani Wulan , Ulfa Maria , Wu Ho-Shing
Published: August 2022

The excessive amount of global plastic produced over the past century, together with poor waste management, has raised concerns about environmental sustainability. Plastic recycling has become a practical approach for diminishing plastic waste and maintaining sustainability among plastic waste management methods. Chemical and mechanical recycling are the typical approaches to recycling plastic waste, with a simple process, low cost, environmentally friendly process, and potential profitability. Several plastic materials, such as polypropylene, polystyrene, polyvinyl chloride, high-density polyethylene, low-density polyethylene, and polyurethanes, can be recycled with chemical and mechanical recycling approaches. Nevertheless, due to plastic waste’s varying physical and chemical properties, plastic waste separation becomes a challenge. Hence, a reliable and effective plastic waste separation technology is critical for increasing plastic waste’s value and recycling rate. Integrating recycling and plastic waste separation technologies would be an efficient method for reducing the accumulation of environmental contaminants produced by plastic waste, especially in industrial uses. This review addresses recent advances in plastic waste recycling technology, mainly with chemical recycling. The article also discusses the current recycling technology for various plastic materials.
Molecular Dynamics Study of the Influence of Nano SiO2 on the Thermodynamic Properties of PMIA Composites
Authors: Liu Bowen , Lv Fangcheng , Fan Xiaozhou , Li Yuxuan , Jiang Bowen
Published: August 2022

The poly-m-phenyleneisophthalamide (PMIA) is widely used in the electrical field due to its numerous favorable characteristics, but its poor thermal conductivity limits its application. In this study, PMIA was modified with nano-silica (SiO2) to improve its thermal and mechanical properties. Using iso-phthalic acid and m-phenylenediamine as monomers, the changes in the thermodynamic properties and microstructure parameters of SiO2-modified PMIA were analyzed using molecular dynamics before and after modification in the temperature range of 250~450 K. It was found that adding SiO2 improves the Young’s modulus and Shear modulus of PMIA, and the mechanical properties of PMIA, and SiO2/PMIA composites deteriorate with increasing temperature, but the mechanical properties of SiO2/PMIA composites are always better than those of pure PMIA in the temperature range of electrical equipment. Meanwhile, after doping SiO2 with the radius of 8 Å, the glass transition temperature of PMIA increases by 27.11 K, and its thermal conductivity increases from 0.249 W m−1 K−1 to 0.396 W m−1 K−1. When SiO2 is added to PMIA, the thermal expansion coefficient of PMIA will decrease in both glass and rubber states, and its thermal stability will improve. In terms of microstructure parameters, the free volume distribution of the SiO2/PMIA model is less easily dispersed than that of the PMIA model, indicating that the addition of SiO2 can improve the related properties of PMIA by hindering the movement of molecular chains.
Microstructural and Micromechanical Characterization of Feedstock for Cold Spray Additive Manufacturing and Processing
Authors: Sousa Bryer C. , Tsaknopoulos Kyle , Cote Danielle L.
Published: August 2022

Due to the processes solid-state nature, cold gas-dynamic spray metal additive manufacturing may be considered microstructurally and micromechanically retentive, such that properties of the feedstock material are refined and partially retained, influencing component performance. As a result, cold spray processing enables unique freedoms regarding feedstock, which can be pre-processed using chemical, thermal, and mechanical treatments to produce powder properties that achieve finely controlled consolidations with application-specific behaviors. Given such features of the cold spray process, the present review article is concerned with the through-process integration of mechanically and microstructurally characterized feedstocks for optimizable cold spray metal additive manufacturing. Therefore, in this paper, we consider how nanoindentation (dynamic, static, and quasi-static) was coupled with microstructural characterization for experimental feedstock evaluation, testing, and characterization. Atomized aluminum alloys, atomized stainless steel, and copper feedstocks, among others, were considered. Accordingly, the review validates how microparticle feedstock pre-processing and characterization in cold spray metal additive manufacturing and processing lead to controllable component performance and properties.
Recent Advances in Catalytic Pyrolysis of Municipal Plastic Waste for the Production of Hydrocarbon Fuels
Authors: Pal Shashank , Kumar Anil , Sharma Amit Kumar , Ghodke Praveen Kumar , Pandey Shyam , Patel Alok
Published: August 2022

Currently, the resources of fossil fuels, such as crude oil, natural gas, and coal, are depleting day by day due to increasing energy demands. Nowadays, plastic items have witnessed a substantial surge in manufacturing due to their wide range of applications and low cost. Therefore, the amount of plastic waste is increasing rapidly. Hence, the proper management of plastic wastes for sustainable technologies is the need of the hour. Chemical recycling technologies based on pyrolysis are emerging as the best waste management approaches due to their robustness and better economics. However, research on converting plastic waste into fuels and other value-added goods has yet to be undertaken, and more R&D is required to make waste-plastic-based fuels economically viable. In this review article, the current status of the plastic waste pyrolysis process is discussed in detail. Process-controlling parameters such as temperature, pressure, residence time, reactor type, and catalyst dose are also investigated in this review paper. In addition, the application of reaction products is also described in brief. For example, plasto-oil obtained by catalytic pyrolysis may be utilized in various sectors, e.g., transportation, industrial boilers, and power generation. On the other hand, byproducts, such as solid residue (plasto-char), could be used as a road construction material or to make activated carbon or graphenes, while the non-condensable gases have a good potential to be utilized as heating/energy source.
A Novel Control Algorithm of the Air Supply Subsystem: Based on Dynamic Modeling of Proton Exchange Membrane Fuel Cell
Authors: Wang Pengyu , Ma Yangyang , Li Jianhua , Gao Yukun , Zhang Yunrui , Ma Denghui
Published: August 2022

In this paper, a novel second-order active disturbance rejection control (2-ADRC) algorithm is proposed to optimize the control of the air supply subsystem for Proton Exchange Membrane Fuel Cell (PEMFC). To improve the optimal control effect of the air supply subsystem for PEMFC, the modeling theory of the air supply subsystem considering dynamic characteristics of the PEMFC system is first studied, and the dynamic Simulink model of the PEMFC system is established and verified. Then, the optimal oxygen excess ratio (OER) parameters under different load currents are obtained, and the optimal OER parameters are also used as the OER control reference for the designed algorithms. In addition, a 2-ADRC algorithm is designed and proposed to make the actual OER parameters close to the optimal OER in real time. Furthermore, compared with PID and MPC algorithms, the 2-ADRC algorithm can comprehensively consider the two parameters of mass flow and pressure ratio to make the compressor work in the high-efficiency zone and improve the net power and efficiency of the PEMFC system.
Special Issue on “Tailoring Polymeric Materials for Specific Applications”
Authors: Stewart Katherine M. E.
Published: August 2022

Polymers are a vast class of materials that are highly tailorable to a wide variety of applications and can be modified in numerous ways [...]
End-to-End Entanglement Generation Strategies: Capacity Bounds and Impact on Quantum Key Distribution
Authors: Manzalini Antonio , Amoretti Michele
Published: August 2022

A first quantum revolution has already brought quantum technologies into our everyday life for decades: in fact, electronics and optics are based on the quantum mechanical principles. Today, a second quantum revolution is underway, leveraging the quantum principles of superposition, entanglement and measurement, which were not fully exploited yet. International innovation activities and standardization bodies have identified four main application areas for quantum technologies and services: quantum secure communications, quantum computing, quantum simulation, and quantum sensing and metrology. This paper focuses on quantum secure communications by addressing the evolution of Quantum Key Distribution (QKD) networks (under early exploitation today) towards the Quantum-ready networks and the Quantum Internet based also on entanglement distribution. Assuming that management and control of quantum nodes is a key challenge under definition, today, a main obstacle in exploiting long-range QKD and Quantum-ready networks concerns the inherent losses due to the optical transmission channels. Currently, it is assumed that a most promising way for overcoming this limitation, while avoiding the presence of costly trusted nodes, it is to distribute entangled states by means of Quantum Repeaters. In this respect, the paper provides an overview of current methods and systems for end-to-end entanglement generation, with some simulations and a discussion of capacity upper bounds and their impact of secret key rate in QKD systems.
Immigrant Women’s Protagonism: Exercising Leadership Roles in Ethnic Churches at the Time of the Pandemic in Italy
Authors: Molli Samuele Davide
Published: August 2022

This paper discusses the protagonism expressed by immigrant women in religion via a series of leadership roles and expands on this theme by considering the pandemic as an emblematic period in which such female activism revealed itself. While the literature gives important details on gender inequalities generated by COVID-19, this article brings to attention agency, resilience and innovation. The case of catholic ethnic churches in Italy, a country particularly hit by the implications of COVID-19, is the empirical field. This paper uses qualitative data obtained through prolonged fieldwork (2018–2022), allowing to discuss the role of ethnic churches before and after the pandemic. The empowerment processes of women in religion and their leading role in terms of welfare provision and activism are detailed, concluding by considering the implications of these. While public institutions were in trouble, religious minorities, and notably their female members, acted to ensure the survival of non-Italian citizens.
Looking to Autoethnography as Spiritual Practice
Authors: Bilgen Wendy Anne
Published: August 2022

In this autoethnographic account, I explore through creative analytic practice (CAP) how autoethnography has become a practice for spiritual connection. Inspired by Martin Buber’s I-Thou philosophy, I discuss how autoethnographic encounters have the potential to emulate what is characterized by Buber as encounters with an Eternal Thou. In Buber’s conceptualization, when an individual I encounters a Thou, in a dialogical relationship of mutual honor and embrace of shared humanity, an Eternal Thou encounter is experienced. The qualities of the I-Thou encounter are mirrored in autoethnography as the autoethnographer (I) and the reader/participant (Thou) share a numinous, sacred, spiritual exchange. Processes inherent to autoethnographic work enable the conditions wherein the sacredness of I-Thou encounters are nourished. I invite the reader to wonder with me about the ways that authentic, vulnerable, and critical engagement with one’s own story paves the way for I-Thou experiences to be ignited and imaginative possibilities multiplied so that individual and social transformation might follow. Finally, I question whether autoethnography might help fill a gap in our current spiritual research paradigms.
Myth, Meaning, and the Work of Life: Enuma Elish and the Garden of Eden (Genesis 2:4–3:24) on the Value of Human Labor and Memory
Authors: Balogh Amy L.
Published: August 2022

This article offers a new comparison of the ancient Mesopotamian story Enuma Elish and the biblical Garden of Eden story (Genesis 2:4–3:24) as a case study that demonstrates how attention to myth theory and comparative method might improve studies of ancient Southwest Asian literatures. This comparison illustrates the connection between myth, meaning making, and the lived experiences that produced and perpetuated these myths by focusing on the cultural value of work and memory as expressed in both narratives. In contrast to previous modes of comparison that conclude with claims to the Bible’s superiority, this comparison uses tools from myth studies and comparative religion toward a clearer understanding of the cultural messaging of both myths regarding the purpose of human life.
The Absence of God in J. M. Barrie’s Post-War Writings: Mary Rose (1920) and Courage (1922)
Authors: Pazdziora John Patrick
Published: August 2022

J. M. Barrie (1860–1937) remains best known as the creator of Peter Pan (1904), celebrated as a whimsical eccentric who wrote sad stories about lost children. In his own day, however, he was respected as Scotland’s leading dramatist and a trenchant social critic. His writings from the years following the First World War are much darker in tone than his earlier work, as a series of intense personal bereavements shook his aesthetic embrace of Christian Humanism. God exists in Barrie’s post-war works as the presence of absence, a vacancy where the divine ought to be but where an inexplicable experience of bereavement hangs instead. This paper considers the nature of God’s absence in two of Barrie’s major post-war works, the drama Mary Rose (1920) and the lecture Courage (1922), through the interrelated images of the crucified body of Christ and the absent λόγος.
Vulnerability in a Populated Coastal Zone and Its Influence by Oil Wells in Santa Elena, Ecuador
Authors: Herrera-Franco Gricelda , Montalván F. Javier , Velastegui-Montoya Andrés , Caicedo-Potosí Jhon
Published: August 2022

The oil industry requires studies of the possible impacts and risks that exploration, exploitation, and industrialization can cause to the environment and communities. The main objective of this study was to assess the vulnerability caused by oil wells of the Salinas and La Libertad cantons in Ecuador by proposing a multi-criteria spatial analysis methodology that would aid in land-use planning and management. The proposed methodology relates the variables of distance, identification of gas emission from oil wells, permeability, and the state of oil wells (DIPS). The methodology consists of: (i) the diagnosis of oilfield wells; (ii) environmental considerations of productive wells, wells in temporary abandonment, and wells in permanent abandonment; (iii) the vulnerability assessment of both intrinsic and extrinsic aspects of the wells; and (iv) the development of a vulnerability map and recommendations for land management. The results showed 462 wells in the study area, of which 92% were shown to be located in urban areas. Of the total, 114 wells were considered to be productive wells, 89% of which are in urban areas. The vulnerability map identified the areas to be addressed, which coincided with coastal and urban areas associated with oil production. Our main recommendation is to elaborate land-use planning regulations and build safety infrastructure around the wells to guarantee their distance from houses, beaches, and tourism-development sites. The vulnerability map was shown to serve as an essential diagnostic for decision making in managing oil territories, especially in coastal areas.