bluuebunny/crossref_metadata_2025 huggingface dataset:
Hyaluronic Acid-Coated Chitosan Nanoparticles as an Active Targeted Carrier of Alpha Mangostin for Breast Cancer Cells
Authors: Meylina Lisna , Muchtaridi Muchtaridi , Joni I Made , Elamin Khaled M. , Wathoni Nasrul
Published: February 2023

Alpha mangostin (AM) has potential anticancer properties for breast cancer. This study aims to assess the potential of chitosan nanoparticles coated with hyaluronic acid for the targeted delivery of AM (AM-CS/HA) against MCF-7 breast cancer cells. AM-CS/HA showed a spherical shape with an average diameter of 304 nm, a polydispersity index of 0.3, and a negative charge of 24.43 mV. High encapsulation efficiency (90%) and drug loading (8.5%) were achieved. AM released from AM-CS/HA at an acidic pH of 5.5 was higher than the physiological pH of 7.4 and showed sustained release. The cytotoxic effect of AM-CS/HA (IC50 4.37 µg/mL) on MCF-7 was significantly higher than AM nanoparticles without HA coating (AM-CS) (IC50 4.48 µg/mL) and AM (IC50 5.27 µg/mL). These findings suggest that AM-CS/HA enhances AM cytotoxicity and has potential applications for breast cancer therapy.
Gelatin-Based Hydrogels: Potential Biomaterials for Remediation
Authors: Andreazza Robson , Morales Amaia , Pieniz Simone , Labidi Jalel
Published: February 2023

Hydrogels have become one of the potential polymers used with great performance for many issues and can be promoted as biomaterials with highly innovative characteristics and different uses. Gelatin is obtained from collagen, a co-product of the meat industry. Thus, converting wastes such as cartilage, bones, and skins into gelatin would give them added value. Furthermore, biodegradability, non-toxicity, and easy cross-linking with other substances can promote polymers with high performance and low cost for many applications, turning them into sustainable products with high acceptance in society. Gelatin-based hydrogels have been shown to be useful for different applications with important and innovative characteristics. For instance, these hydrogels have been used for biomedical applications such as bone reconstruction or drug delivery. Furthermore, they have also shown substantial performance and important characteristics for remediation for removing pollutants from water, watercourse, and effluents. After its uses, gelatin-based hydrogels can easily biodegrade and, thus, can be sustainably used in the environment. In this study, gelatin was shown to be a potential polymer for hydrogel synthesis with highly renewable and sustainable characteristics and multiple uses.
Promising Agromaterials Based on Biodegradable Polymers: Polylactide and Poly-3-Hydroxybutyrate
Authors: Tertyshnaya Yulia Victorovna , Podzorova Maria Victorovna , Varyan Ivetta Aramovna , Tcherdyntsev Victor Victorovich , Zadorozhnyy Mikhail Yurievich , Medvedeva Elena Valerievna
Published: February 2023

Electrospun fabrics have unique properties due to their uniform morphology and high surface area to volume ratio. Ultrathin nonwoven fabrics are produced for many applications: biomedical, nanosensors, tissue engineering and filtration systems. In this work, nonwoven polylactide, polylactide/natural rubber, poly-3-hydroxybutyrate, and poly-3-hydroxybutyrate/nitrile butadiene rubber fabrics were prepared by electrospinning methods. The obtained fabric samples were used as substrates for the growth of winter wheat seeds “Yubileinaya 100” (Triticum aestivum L.). The stimulating effect of polymer substrates on seed germination and plant growth was shown. The structure and properties of nonwoven agromaterials were controlled by differential scanning calorimetry, IR-spectroscopy, and optical microscopy. The mechanical properties of the obtained fabrics before and after their utilization as substrates were studied. After the wheat growing experiment, the degree of crystallinity of PHB and PHB/NBR samples decreased by 12% and they completely lost their mechanical properties. It is shown that the main factors providing the efficiency of seed growth technology on polymer substrates are the chemical nature and structure of the biodegradable matrix.
Synthesis, Characterization, and Application of Dichloride (5,10,15,20-Tetraphenylporphyrinato) Antimony Functionalized Pectin Biopolymer to Methylene Blue Adsorption
Authors: Soury Raoudha , Alhar Munirah Sulaiman Othman , Jabli Mahjoub
Published: February 2023

In this work, pectin biopolymers were functionalized with dichloride (5,10,15,20-tetraphenylporphyrinato) antimony [Sb(TPP)Cl2] at various compositions (0.5%, 1%, and 2%). The prepared compounds were characterized with several analytical methods, including X-ray fluorescence (XRF) spectrometry, Fourier-transform infrared spectroscopy (FT-IR), electrospray ionization mass spectrometry (EIS), scanning electron microscope (SEM), X-ray diffraction (XRD), and thermogravimetric-differential thermal (TGA/DTG) analysis. The XRF technique evidenced the presence of Sb metal in the composite beads. FT-IR suggested that the interaction between pectin and the [Sb(TPP)Cl2] complex was assured by inter- and intramolecular C-H⋯O, C-H⋯Cl hydrogen bonds and weak C–H⋯Cg π interactions (Cg is the centroid of the pyrrole and phenyl rings). The morphological features of the prepared polymeric beads were affected by the addition of [Sb(TPP)Cl2] particles, and the surface became rough. The thermal residual mass for the composite beads (29%) was more important than that of plain beads (23%), which confirmed the presence of inorganic matter in the modified polymeric beads. At 20 °C, the highest adsorption amounts of methylene blue were 39 mg/g and 68 mg/g for unmodified pectin and pectin-[Sb(TPP)Cl2] beads, respectively. The adsorption mechanism correlated well with the kinetic equation of the second order and the isotherm of Freundlich. The prepared polymeric beads were characterized as moderate-to-good adsorbents. The calculated thermodynamic parameters demonstrated an exothermic and thermodynamically nonspontaneous mechanism.
Study on Degradation of Natural Rubber Latex Using Hydrogen Peroxide and Sodium Nitrite in the Presence of Formic Acid
Authors: Wisetkhamsai Kraiwut , Patthaveekongka Weerawat , Arayapranee Wanvimon
Published: February 2023

Liquid natural rubber (LNR), a depolymerized natural rubber (NR) consisting of shorter chains, was prepared via oxidative degradation using NaNO2 and H2O2 degrading agents in the presence of HCOOH. The influence of reagent concentrations, temperature, and reaction time on the number-average molecular weight (Mn) was studied. Results showed the higher concentration of H2O2 and HCOOH employed faster degradative rates. However, a higher concentration of NaNO2 decreased the Mn reduction. Prolonged reaction time and high temperature resulted in a product with low Mn. FTIR spectra indicated the synthesized LNR contained hydroxyl end groups resulting from the breaking of the NR chains at an acidic pH, whereas a carboxyl terminated LNR was formed at an alkaline pH. SEM micrographs showed the latex particles of LNR were spherical and smaller compared to NR. The experimental results showed the reaction orders of [H2O2], [HCOOH], and [NaNO2] were 1.58, 0.79, and −0.65, respectively. In addition, the pre-exponential factor and activation energy were 1.04 × 109 M−1.72 t−1 and 78.66 kJ/mol, respectively. Based on TGA analysis, the thermal stability of the rubber depended on its Mn. The LNR containing functional end groups exhibited thermal instability and could be a starting material for many applications.
Interaction of Lysozyme with Poly(L-lysine)/Hyaluronic Acid Multilayers: An ATR-FTIR Study
Authors: Velk Natalia , Keller Janos , Duschl Claus , Brezesinski Gerald , Volodkin Dmitry
Published: February 2023

Polyelectrolyte multilayers (PEM) loaded with bioactive molecules such as proteins serve as excellent mimics of an extracellular matrix and may find applications in fields such as biomedicine and cell biology. A question which is crucial to the successful employment of PEMs is whether conformation and bioactivity of the loaded proteins is preserved. In this work, the polarized attenuated total reflection Fourier transform infrared (ATR-FTIR) technique is applied to investigate the conformation of the protein lysozyme (Lys) loaded into the poly(L-lysine)/hyaluronic acid (PLL/HA) multilayers. Spectra are taken from the protein in the PEMs coated onto an ATR crystal during protein adsorption and desorption. For comparison, a similar investigation is performed for the case of Lys in contact with the uncoated crystal. The study highlights the presence of both “tightly” and “poorly bound” Lys fractions in the PEM. These fractions differ in their conformation and release behavior from the PEM upon washing. Comparison of spectra recorded with different polarizations suggests preferential orientation of alpha helical structures, beta sheets and turns in the “tightly bound” Lys. In contrast, the “poorly bound” fraction shows isotropic orientation and its conformation is well preserved.
Boosting the Antibacterial Performance of Natural Rubber Latex Foam by Introducing Silver-Doped Zinc Oxide
Authors: Masa Abdulhakim , Jehsoh Nureeyah , Dueramae Sawitree , Hayeemasae Nabil
Published: February 2023

Natural rubber (NR) latex foam is one of the rubber products that are increasingly in demand in the market. This is simply because of its lightweight, good thermal insulation, and resilience. The applications of NR latex foam are mostly for pillows and mattresses. This has resulted in these products requiring antibacterial performance which is very important for the safety of the end-users. In this study, the antibacterial NR latex foam was prepared by incorporating the silver-doped zinc oxide (Ag-doped ZnO) into the NR latex foam. Ag-doped ZnO was prepared by microwave-assisted method and then characterized through morphological characteristics and X-ray diffraction (XRD). The content of Ag doped onto ZnO was designed by varying the AgNO3 content at 15 wt%, 50 wt%, and 100 wt% of ZnO. The results confirmed that the Ag was successfully doped onto ZnO. The silver particles were found to be in the 40–50 nm range, where the size of ZnO ranges between 300 and 400 nm, and the Ag attached to the ZnO particles. The XRD patterns of Ag-doped ZnO correspond to planes of hexagonal wurtzite ZnO structure and cubic metallic Ag. This Ag-doped ZnO was further added to NR latex foam. It was observed that Ag-doped ZnO did not affect the physical properties of the NR latex foam. However, it is clear that both the inhibition zone and percent reduction of bacteria (e.g., E. coli and S. aureus) were enhanced by the addition of Ag-doped ZnO. It showed a decrease in the amount of cell growth over contact time. The content of 100 wt% AgNO3 could reduce E. coli and S. aureus up to 64.72% and 58.90%, respectively, when samples were maintained for 24 h. This study provides a scientific understanding of how Ag-doped ZnO could facilitate the development of eventual rubber foam products based on the respective results.
Enhanced Mechanical Property of Polyamide-6/Graphite Sheet Composites with Segregated 3D Network Binary Structure for High Thermal Conductivity
Authors: Gao Yao , Li Yong , Kong Xiangwei , Ma Meng
Published: February 2023

Segregated conductive polymer composites exhibit excellent electrical properties with a low percolation threshold. However, the mechanical properties of the segregated conductive polymer composites were always poor because the conductive fillers at the interfaces hinder polymer chain diffusion and thus lead to weak interfacial interaction between the conductive fillers and the polymer matrix. In this paper, polyamide-6 and polyamide-612 microspheres were synthesized via the in situ anionic ring opening of caprolactam and laurolactam. Segregated graphite sheets/polyamide-6(GS/PA6) and polyamide-612(PA612) composites with good mechanical properties were realized via high-pressure solid-phase compression molding. The microstructures of the composite samples were observed by scanning electron microscopy, which showed that the formation of a GS-conductive network at the PA6 granule interfaces in the segregated conductive structures and the adopting of PA612 considerably improved the interfacial adhesion of the composites. A superior impact strength of 5.1 kJ/m2 was achieved with 50 wt% PA612 loading owing to improvements in the interface compatibility between PA6 and GS. The composites possessed an ultralow percolation threshold, which was ascribed to the segregated network structure being successfully constructed inside the material. As for GS/PA6 composites, the combination of segregated GS-conductive networks achieved an ultralow percolation of 2.8 vol%. The percolation of 80PA6/20PA612-GS composites was slightly higher, measuring up to 3.2 vol%. Moreover, the thermal conductivity of the 80PA6/20PA612-GS composites increased from 0.26 to around 0.5 W/(m·K), which was 1.9 times larger than the pure polyamide.
Effect of Almond Skin Waste and Glycidyl Methacrylate on Mechanical and Color Properties of Poly(ε-caprolactone)/Poly(lactic acid) Blends
Authors: Valdés Arantzazu , Dominici Franco , Fortunati Elena , Kenny Jose María , Jiménez Alfonso , Garrigós María Carmen
Published: February 2023

Blending Poly(lactic acid) (PLA) and Poly(ε-caprolactone) (PCL) is a promising strategy to enhance the properties of biodegradable materials. However, these compounds are thermodynamically immiscible and, consequently, compatibilization is required during polymer blending. Reinforced biocomposites can be obtained by adding agricultural wastes generated by industries which are forced to consider waste treatment methods to prevent environmental concerns. Novel PCL/PLA blends were proposed based on the addition of 10 wt.% almond shell (AS) waste combined with 3 wt.% glycidyl methacrylate (GMA) as a compatibilizer. Different PCL-, PLA-, and PCL/PLA-based blends at different percentages (75:25, 50:50, 25:75, 15:85) added with GMA and AS were obtained. The color results highlighted the lower transparency and brownish tone of the studied formulations after the addition of AS. The addition of PCL provided a positive effect on PLA’s ductility due to its intrinsically higher flexibility. The combination of GMA and AS improved the mechanical properties of PCL, PLA, and 50:50 controls by reducing yield strength, yield strength at break, and elongation at break values. The 75:25_GMA_AS formulation showed a homogeneous visual appearance, low transparency, and desirable mechanical properties for rigid food packaging applications, reducing the final material cost through the revalorization of AS.
Antibacterial Activity of Ulva/Nanocellulose and Ulva/Ag/Cellulose Nanocomposites and Both Blended with Fluoride against Bacteria Causing Dental Decay
Authors: Hamouda Ragaa A. , Qarabai Fauzia A. K. , Shahabuddin Fathi S. , Al-Shaikh Turki M. , Makharita Rabab R.
Published: February 2023

One of the most prevalent chronic infectious disorders is tooth decay. Acids produced when plaque bacteria break down sugar in the mouth cause tooth decay. Streptococcus mutans and Lactobacillus acidophilus are the most prominent species related to dental caries. Innovative biocidal agents that integrate with a biomaterial to prevent bacterial colonization have shown remarkable promise as a result of the rapid advancement of nanoscience and nanotechnology. In this study, Ulva lactuca was used as a cellulose source and reducing agent to synthesize nanocellulose and Ulva/Ag/cellulose/nanocomposites. The characterizations of nanocellulose and Ulva/Ag/cellulose/nanocomposites were tested for FT-IR, TEM, SEM, EDS, XRD, and zeta potential. Ulva/Ag/cellulose/nanocomposites and Ulva/nanocellulose, both blended with fluoride, were tested as an antibacterial against S. mutans ATCC 25175 and L. acidophilus CH-2. The results of the SEM proved that nanocellulose is filament-shaped, and FT-IR proved that the functional groups of Ulva/nanocellulose and Ulva/Ag/cellulose/nanocomposites and cellulose are relatively similar but present some small diffusion in peaks. The TEM image demonstrated that the more piratical size distribution of Ulva/Ag/cellulose/nanocomposites ranged from 15 to 20 nm, and Ulva/nanocellulose ranged from 10 to 15 nm. Ulva/Ag/cellulose/nanocomposites have higher negativity than Ulva/nanocellulose. Ulva/Ag/cellulose/nanocomposites and Ulva/nanocellulose possess antibacterial activity against S. mutans ATCC 25175 and L. acidophilus CH-2, but Ulva/Ag/cellulose/nanocomposites are more effective, followed by that blended with fluoride. It is possible to use Ulva/Ag/cellulose/nanocomposites as an antimicrobial agent when added to toothpaste. It is promising to discover an economic and safe nanocomposite product from a natural source with an antimicrobial agent that might be used against tooth bacteria.
Assessment of Zataria Multiflora Essential Oil—Incorporated Electrospun Polyvinyl Alcohol Fiber Mat as Active Packaging
Authors: Moradinezhad Farid , Hedayati Sara , Ansarifar Elham
Published: February 2023

In this study, an active packaging containing Zataria multiflora essential oil (ZMEO), a powerful natural antimicrobial agent, encapsulated into polyvinyl alcohol (PVA) fiber via electrospinning is presented. ZMEO was effective on pathogenic bacteria, particularly Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus, Listeria monosytogene), fungi and yeasts (Aspergillus fumigatus, Candida albicans). Results showed that the scanning electron microscopy (SEM) images of fibers had a bead-free and uniform structure. Fourier-transform infrared (FTIR) revealed that ZMEO was encapsulated into PVA through a physical process, without chemical interaction between the ingredients. Strawberries treated with PVA/ZMEO significantly (p < 0.05) preserved the anthocyanin (18.64%), total phenols (12.95%), antioxidant (22.72%), soluble solids (6.44%), titratable acidity (20.88%), firmness (27.2%), and color (15.55%) compared to the control sample during 15 days of cold storage. According to these findings, electrospinning was an efficient method for encapsulating bioactive compounds. ZMEO loaded into PVA fiber delayed the physiological and biochemical changes of fruits and extended the fruit’s shelf-life. This study revealed the benefits of incorporating ZMEO into PVA fiber mats, which could lead to new possibilities for active packaging.
The Elasticity of Polymer Melts and Solutions in Shear and Extension Flows
Authors: Subbotin Andrey V. , Malkin Alexander Ya. , Kulichikhin Valery G.
Published: February 2023

This review is devoted to understanding the role of elasticity in the main flow modes of polymeric viscoelastic liquids—shearing and extension. The flow through short capillaries is the central topic for discussing the input of elasticity to the effects, which are especially interesting for shear. An analysis of the experimental data made it possible to show that the energy losses in such flows are determined by the Deborah and Weissenberg numbers. These criteria are responsible for abnormally high entrance effects, as well as for mechanical losses in short capillaries. In addition, the Weissenberg number determines the threshold of the flow instability due to the liquid-to-solid transition. In extension, this criterion shows whether deformation takes place as flow or as elastic strain. However, the stability of a free jet in extension depends not only on the viscoelastic properties of a polymeric substance but also on the driving forces: gravity, surface tension, etc. An analysis of the influence of different force combinations on the shape of the stretched jet is presented. The concept of the role of elasticity in the deformation of polymeric liquids is crucial for any kind of polymer processing.
Promotion of In Vitro Osteogenic Activity by Melt Extrusion-Based PLLA/PCL/PHBV Scaffolds Enriched with Nano-Hydroxyapatite and Strontium Substituted Nano-Hydroxyapatite
Authors: Kontogianni Georgia-Ioanna , Bonatti Amedeo Franco , De Maria Carmelo , Naseem Raasti , Melo Priscila , Coelho Catarina , Vozzi Giovanni , Dalgarno Kenneth , Quadros Paulo , Vitale-Brovarone Chiara , Chatzinikolaidou Maria
Published: February 2023

Bone tissue engineering has emerged as a promising strategy to overcome the limitations of current treatments for bone-related disorders, but the trade-off between mechanical properties and bioactivity remains a concern for many polymeric materials. To address this need, novel polymeric blends of poly-L-lactic acid (PLLA), polycaprolactone (PCL) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) have been explored. Blend filaments comprising PLLA/PCL/PHBV at a ratio of 90/5/5 wt% have been prepared using twin-screw extrusion. The PLLA/PCL/PHBV blends were enriched with nano-hydroxyapatite (nano-HA) and strontium-substituted nano-HA (Sr-nano-HA) to produce composite filaments. Three-dimensional scaffolds were printed by fused deposition modelling from PLLA/PCL/PHBV blend and composite filaments and evaluated mechanically and biologically for their capacity to support bone formation in vitro. The composite scaffolds had a mean porosity of 40%, mean pores of 800 µm, and an average compressive modulus of 32 MPa. Polymer blend and enriched scaffolds supported cell attachment and proliferation. The alkaline phosphatase activity and calcium production were significantly higher in composite scaffolds compared to the blends. These findings demonstrate that thermoplastic polyesters (PLLA and PCL) can be combined with polymers produced via a bacterial route (PHBV) to produce polymer blends with excellent biocompatibility, providing additional options for polymer blend optimization. The enrichment of the blend with nano-HA and Sr-nano-HA powders enhanced the osteogenic potential in vitro.
Multilayered Composites with Carbon Nanotubes for Electromagnetic Shielding Application
Authors: Bertašius Povilas , Plyushch Artyom , Macutkevič Jan , Banys Jūras , Selskis Algirdas , Platnieks Oskars , Gaidukovs Sergejs
Published: February 2023

Bulk polylactic acid (PLA)/multiwall carbon nanotube (MWCNT) composites were prepared and investigated in wide frequency ranges (20 Hz–1 MHz and 24–40 GHz). It was determined that the percolation threshold in bulk PLA/MWCNT composites is close to 0.2 vol.% MWCNT. However, the best microwave dielectric properties and absorption were observed in composites with 3.0–5.0 vol.% MWCNT. Therefore, for future investigations, we selected layered (laminate) polymeric structures with gradual changes in MWCNT concentration from 0.2 to 8.0 vol.% MWCNT. Two approaches to laminate structure designs were examined and compared: a five-layer composite and a nine-layer composite that included four pure PLA middle layers. The addition of MWCNT enhanced the elastic modulus by up to 1.4-fold and tensile strength by up to 1.2-fold, with the best performance achieved at 5.0 vol.% loading. High microwave shielding was observed for these layered PLA/MWCNT structures with a gradient change in MWCNT concentration (up to 26 dB in both transmission and absorption coefficients) in the broad frequency range (from 24 to 40 GHz). Obtained structures are highly anisotropic, and the absorption coefficient is 2–5 dB higher in the direction of MWCNT concentration increase; however, the transmission coefficient is the same in both directions. The properties of microwave absorption are mainly unaffected by the additional polymeric layers. The absorption of the layered structure is greater than the absorption of single-layer composites with an optimal MWCNT concentration of the same thickness. The proposed laminate structure design is promising in the field of efficient electromagnetic shielding.
Biochemical and Microstructural Characteristics of Collagen Biopolymer from Unicornfish (Naso reticulatus Randall, 2001) Bone Prepared with Various Acid Types
Authors: Fatiroi Nurul Syazwanie , Jaziri Abdul Aziz , Shapawi Rossita , Mokhtar Ruzaidi Azli Mohd , Noordin Wan Norhana Md. , Huda Nurul
Published: February 2023

Biopolymer-like collagen has great industrial potential in terms of its excellent properties, such as strong biocompatibility, high degradability, and low antigenicity. Collagen derived from fish by-products is preferable as it is safer (free from transmittable diseases) and acceptable to most religious beliefs. This study aimed to characterize the unicornfish (Naso reticulatus Randall, 2001) bone collagens prepared with different type of acids, i.e., acetic acid, lactic acid, and citric acid. A higher yield (Y) (p < 0.05) was obtained in the citric-acid-soluble collagen (CASC) (Y = 1.36%), followed by the lactic-acid-soluble collagen (LASC) (Y = 1.08%) and acetic-acid-soluble collagen (AASC) (Y = 0.40%). All extracted collagens were classified as type I due to the presence of 2-alpha chains (α1 and α2). Their prominent absorption spectra were located at the wavelengths of 229.83 nm to 231.17 nm. This is similar to wavelengths reported for other fish collagens. The X-ray diffraction (XRD) and infrared (IR) data demonstrated that the triple-helical structure of type I collagens was still preserved after the acid-extraction process. In terms of thermal stability, all samples had similar maximum transition temperatures (Tmax = 33.34–33.51 °C). A higher relative solubility (RS) of the unicornfish bone collagens was observed at low salt concentration (0–10 g/L) (RS > 80%) and at acidic condition (pH 1.0 to pH 3.0) (RS > 75%). The extracted collagen samples had an irregular and dense flake structure with random coiled filaments. Overall, bones of unicornfish may be used as a substitute source of collagen.
An Experimental Study on the Dilute Phase Pneumatic Conveying of Fat-Filled Milk Powders: Particle Breakage
Authors: Zhang Fuweng , O’Mahony James A. , Miao Song , Cronin Kevin
Published: February 2023

Powder breakage during pneumatic conveying negatively affects the properties of dairy products and causes increased dusting, reduced wettability, and decreased product performance. In particular, particle breakage is a serious issue for fat-filled milk powder (FFMP) which, if it breaks, releases fat that causes odours and leads to sticky blocked pipes. In this work, a conveying rig (dilute phase, positive pressure) with 50 mm diameter food grade stainless steel pipes (1.5 m high and 5 m conveying distance with three 90° bends, two in the vertical plane and one in the horizontal plane) was built as the test system. The effects of operating conditions (conveying air velocity and solid loading rate) on the attrition of FFMP in a dilute phase conveying system were experimentally studied. Four quality characteristics were measured before and after conveying: bulk density, particle size distribution, wettability, and solubility, to access the influence of particle breakage. Conveying air speed shows a significant impact on powder breakage. As air speed increased, more breakage occurred, and the volume mean diameter D[4,3] decreased by around 50%, using the largest conveying air speed of 38 m/s. Bulk density increased accordingly whereas wettability decreased with an increase in air speed, resulting from the higher breakage rate. On other hand, improving the solid loading rate can further reduce the breakage level, but the positive effect is not as good as decreasing air speed.
Lithofacies Characteristics and Pore Controlling Factors of New Type of Permian Unconventional Reservoir in Sichuan Basin
Authors: Li Rong , Xiong Zhifu , Wang Zecheng , Xie Wuren , Li Wenzheng , Hu Jiuzhen
Published: February 2023

Alongside volcanic eruptions in the middle and late Permian, the sedimentary environment and process changed, and the lithofacies characteristics varied conspicuously in the marine deposits of the Sichuan Basin (China). The tuffaceous rocks, as a new type of unconventional reservoir, provide strong evidence for marine and volcanic influences on the lithology and reservoir potential of the rocks. With experimental studies relying on field outcrops, thin sections, scanning electron microscopy and whole-rock X-ray diffraction (XRD), the researchers analyzed the lithofacies characteristics, pore types and controlling factors on the various types of pores in the tuffaceous rocks. We identified three lithofacies types in this new type of Permian reservoir in the Sichuan Basin, namely tuff, sedimentary tuff, and tuffaceous mudstone. The mineral composition of the three lithofacies includes quartz, feldspar, carbonate minerals, pyrite, and clay, among which feldspar is mainly potassium feldspar. Tuff has high tuff content, and the lowest clay and TOC content; tuffaceous mudstones have the highest clay and TOC content, and the lowest tuff content. The pore types of the tuffaceous rocks are mainly nano-scale shrinkage pores, with a small number of intergranular pores including intragranular pores, intergranular pores, and organic pores. The shrinkage pores account for 81.9% of the total pores, and organic pores account for 11.2% of the total pores. In the tuffaceous rocks, the tuff content, quartz and feldspar content, and pyrite content are inversely correlated with porosity, while the clay content and TOC content are positively correlated with porosity. The porosity of tuff is the lowest, followed by sedimentary tuff, and the porosity of tuffaceous mudstone is the highest. Tuffaceous rocks form many micropores in the process of devitrification. Organic matter pyrolysis and organic acid dissolution also increase the reservoir space and porosity of the reservoir. This new type of reservoir has the ability of hydrocarbon accumulation along with the reservoir performance, and thus it has greater exploration prospects.
Surface Topography Model of Ultra-High Strength Steel AF1410 Based on Dynamic Characteristics of Milling System
Authors: Xu Jin , Yan Fuwu , Wan Xiaojin , Li Yan , Zhu Qiang
Published: February 2023

AF1410 is a low carbon high alloy ultra-high strength steel. It not only has high strength and high toughness, but also has a high stress corrosion resistance. However, due to the characteristics of hard quality and poor thermal conductivity, AF1410 is a difficult material to process. In the process of milling, the geometric factors of process parameters, the flexible deformation of milling cutter and the flutter of the process system all affect the surface roughness, which makes it difficult to predict the surface roughness of milling parts. In order to solve this problem, a prediction model for surface topography of ultrahigh strength steel AF1410 was studied. To solve this problem, this paper studies the formation of milling surface topography, considers the dynamic displacement of the milling system, proposes a modeling method of surface topography based on the dynamic characteristics of the milling system and forms a prediction model. On this basis, the surface topography of ultra-high strength steel is simulated and analyzed, and the accuracy of the model is verified by experiments. The study realizes the prediction of milling surface topography of AF1410 parts and reveals the formation mechanism of milling surface topography from geometric and physical perspectives.
Bioengineering Applied to Oral Implantology, a New Protocol: “Digital Guided Surgery”
Authors: Fiorillo Luca , Meto Agron , Cicciù Marco
Published: February 2023

Rehabilitative dentistry has made enormous progress in recent years, not only due to the advent of new implant-prosthetic methods, but also thanks to new information technologies that support the doctor. This study aims to present a new implant protocol that involves the application of bioengineering methods. With the application of the finite element analysis, it is possible to evaluate the distribution of the forces of a fixture and possible implant rehabilitation on each patient, even before performing the surgery. This protocol provides for the combination of radiographic images and three-dimensional files to obtain predictable results on possible rehabilitation, guiding its planning in the best possible way. Surely, the evolution of machines and computers will enable the surgeon to carry out and maintain these protocols in a chair-side manner, and to carry out safe and predictable rehabilitations.
Effectiveness of the IoT in Regional Energy Transition: The Smart Bin Case Study
Authors: Ziouzios Dimitris , Dasygenis Minas
Published: February 2023

As part of the European Green Deal, the EU aims to become climate-neutral and reach net-zero greenhouse gas emissions by 2050. Lignite has long dominated the electricity system of Greece, providing cheap and reliable energy, given the abundant and low-cost domestic resources at the cost of increased emission. In line with its national and international commitments to climate action, Greece needs to urgently transform its energy system and overcome its technological lock-ins, paving the way for a net-zero emission economy by the mid-century. The Internet of Things plays a significant role in this direction, providing with its technologies the protection of the environment and creating new jobs. The smart bins constitute an interesting proposal for areas in the energy transition. This research work reflects the current situation in the region of Western Macedonia and proposes the smart bin project as a part of the solution in the transition to the post-lignite era. For this purpose, survey research has been conducted in the municipalities of Greece on waste management technology.
Intentionality and the Diversity of Religion: A Prelude
Authors: Kiem Youngjin
Published: February 2023

The grounds of religious diversity and pluralism have mainly been sought out from without, i.e., from outside the human mind. A striking example is Hick’s idea of the one ultimate reality, which is posited to embrace all the semi-ultimate realities appearing in individual religions. However, the present inquiry adopts a different strategy for coping with the above-mentioned issue. Specifically, in this inquiry, I attempt to find a substantial clue to religious diversity and pluralism from within, i.e., from the intentionality of the mind. This idea, as a descriptive and explanatory hypothesis, consists of the following theses: (I) As suggested by the Husserlian phenomenology interpreted by Sokolowski, there are at least two forms of directedness of the mind: filled and empty intentionalities. (II) In connection with them, two distinct types of religious spirituality emerge: the intentionality of transcendental filling (ITF) and that of transcendental emptying (ITE). (III) The diversity of religion that gives rise to pluralism is, at least in part, due to the different ways in which those two forms of religious minds are combined. With these considerations, we reach a new philosophical foundation of the issue in question, and also obtain a possible theoretical basis for securing an adequate method of religious—and particularly interreligious—studies.
Did Freud Miss the Discovery of Our Spiritual Core?
Authors: Chatlos John Calvin
Published: February 2023

A specific framework of spirituality is presented to direct this dialog between psychoanalysis and religion. The focus is on spirituality as a common and important area of interest. A cognitive-behavioral-theory-based exploration of spirituality identifies experiences of self-worth and dignity as keys to opening a spiritual core that is present in all people. This spiritual core has mystical and numinous characteristics believed to be the foundation of religious traditions. It is elaborated with many specific relationships to the psychoanalytic theory and practice of Freud, Kohut, and Jung, as well as to modern neuroscience and various religious traditions. The personal journey of the author is used to illustrate its foundation, development, and relevance for psychoanalytic, religious, and life experiences, demonstrating how all can work toward a common goal.
Editorial: Gender Asymmetry and Nuns’ Agency in the Asian Buddhist Traditions
Authors: Schneider Nicola
Published: February 2023

Looking at early Indian Buddhist texts and inscriptions, we can generally find gender pairing within the terminology deployed, a situation which is replicated in many texts related to monastic discipline (Vinaya) and in teachings addressed by the Buddha to either his male or female disciples (Skilling 2001) [...]
A Dynamic Approach to Low-Cost Design, Development, and Computational Simulation of a 12DoF Quadruped Robot
Authors: Rahman Md. Hasibur , Alam Saadia Binte , Mou Trisha Das , Uddin Mohammad Faisal , Hasan Mahady
Published: February 2023

Robots equipped with legs have significant potential for real-world applications. Many industries, including those concerned with instruction, aid, security, and surveillance, have shown interest in legged robots. However, these robots are typically incredibly complicated and expensive to purchase. Iron Dog Mini is a low-cost, easily replicated, and modular quadruped robot built for training, security, and surveillance. To keep the price low and its upkeep simple, we designed our quadruped robot in a modular manner. We provide a comparative study of robotic manufacturing cost between our proposed robot and previously established robots. We were able to create a compact femur and tibia structure with sufficient load-bearing capacity. To improve stability and motion efficiency, we considered the novel Watt six-bar linkage mechanism. Using the SolidWorks modeling software, we analyzed the structural integrity of the robot’s components, considering their respective material properties. Furthermore, our research involved developing URDF data for our quadruped robot based on its CAD model. Its gait trajectory is planned using a 14-point Bezier curve. We demonstrate the operation of the simulation model and briefly discuss the robot’s kinematics. Computational methods are emphasized in this research, coupled with the simulation of kinematic and dynamic performances and analytical/numerical modeling.
A Social Robot to Assist in Addressing Disruptive Eating Behaviors by People with Dementia
Authors: Astorga Misael , Cruz-Sandoval Dagoberto , Favela Jesus
Published: February 2023

Socially assistive robots have been proposed to help people with dementia to conduct activities of daily living, facilitate therapeutic interventions or address problematic symptoms associated with the disease. Psychological symptoms of dementia, such as anxiety, apathy or aggression, are the main cause of distress to both people with dementia and caregivers. Caregivers frequently report disruptive eating behaviors as a major cause of concern. These include being distracted while eating, throwing food or refusing to eat. This paper reports the design and evaluation of a social robot aimed at assisting people with dementia with disruptive eating behaviors. We describe the user-centered design process that was followed and the implementation and evaluation of the assistive robot. The assistive robot identifies common challenging behaviors, using mostly computer vision, and incorporates strategies recommended by caregivers to help address them.
Fresh Yield Estimation of Spring Tea via Spectral Differences in UAV Hyperspectral Images from Unpicked and Picked Canopies
Authors: He Zongtai , Wu Kaihua , Wang Fumin , Jin Lisong , Zhang Rongxu , Tian Shoupeng , Wu Weizhi , He Yadong , Huang Ran , Yuan Lin , Zhang Yao
Published: February 2023

At present, spring tea yield is mainly estimated through a manual sampling survey. Obtaining yield information is time consuming and laborious for the whole spring tea industry, especially at the regional scale. Remote sensing yield estimation is a popular method used in large-scale grain crop fields, and few studies on the estimation of spring tea yield from remote sensing data have been reported. This is a similar spectrum of fresh tea yield components to that of the tea tree canopy. In this study, two types of unmanned aerial vehicle (UAV) hyperspectral images from the unpicked and picked Anji white tea tree canopies are collected, and research on the estimation of the spring tea fresh yield is performed using the differences identified in the single and combined chlorophyll spectral indices (CSIs) or leaf area spectral indices (LASIs) while also considering the changes in the green coverage of the tea tree canopy by way of a linear or piecewise linear function. The results are as follows: (1) in the linear model with a single index variable (LMSV), the accuracy of spring tea fresh yield models based on the selected CSIs was better than that based on the selected LASIs as a whole, in which the model based on the curvature index (CUR) was the best with regard to the accuracy metrics; (2) compared to the LMSVs, the accuracy performance of the piecewise linear model with the same index variables (PLMSVs) was obviously improved, with an encouraging root mean square error (RMSE) and validation determination coefficient (VR2); and (3) in the piecewise model with the combined index variables (PLMCVs), its evaluation metrics are also improved, in which the best performance of them was the CUR&CUR model with a RMSE (124.602 g) and VR2 (0.625). It showed that the use of PLMSVs or PLMCVs for fresh tea yield estimation could reduce the vegetation index saturation of the tea tree canopy. These results show that the spectral difference discovered through hyperspectral remote sensing can provide the potential capability of estimating the fresh yield of spring tea on a large scale.
Mapping of Flood-Prone Areas Utilizing GIS Techniques and Remote Sensing: A Case Study of Duhok, Kurdistan Region of Iraq
Authors: M Amen Aumed Rahman , Mustafa Andam , Kareem Dalshad Ahmed , Hameed Hasan Mohammed , Mirza Ayub Anwar , Szydłowski Michał , M. Saleem Bala Kawa
Published: February 2023

One of the most common types of natural disaster, floods can happen anywhere on Earth, except in the polar regions. The severity of the damage caused by flooding can be reduced by putting proper management and protocols into place. Using remote sensing and a geospatial methodology, this study attempts to identify flood-vulnerable areas of the central district of Duhok, Iraq. The analytical hierarchy process (AHP) technique was used to give relative weights to 12 contributing parameters, including elevation, slope, distance from the river, rainfall, land use land cover, soil, lithology, topographic roughness index, topographic wetness index, aspect, the sediment transport index, and the stream power index in order to calculate the Flood Hazard Index (FHI). The relative importance of each criterion was revealed by a sensitivity analysis of the parameter values. This research developed a final flood susceptibility map and identified high-susceptible zones. This was classified anywhere from very low to very high classifications for its potential flood hazard. The generated map indicates that 44.72 km2 of the total land area of the study area in Duhok city has a very high susceptibility to flooding, and that these areas require significant attention from government authorities in order to reduce flood vulnerability.
Reference-Based Super-Resolution Method for Remote Sensing Images with Feature Compression Module
Authors: Zhang Jiayang , Zhang Wanxu , Jiang Bo , Tong Xiaodan , Chai Keya , Yin Yanchao , Wang Lin , Jia Junhao , Chen Xiaoxuan
Published: February 2023

High-quality remote sensing images play important roles in the development of ecological indicators’ mapping, urban-rural management, urban planning, and other fields. Compared with natural images, remote sensing images have more abundant land cover along with lower spatial resolutions. Given the embedded longitude and latitude information of remote sensing images, reference (Ref) images with similar scenes could be more accessible. However, existing traditional super-resolution (SR) approaches always depend on increases in network depth to improve performance, which limits the acquisition and application of high-quality remote sensing images. In this paper, we proposed a novel, reference-image-based, super-resolution method with feature compression module (FCSR) for remote sensing images to alleviate the above issue while effectively utilizing high-resolution (HR) information from Ref images. Specifically, we exploited a feature compression branch (FCB) to extract relevant features in feature detail matching with large measurements. This branch employed a feature compression module (FCM) to extract features from low-resolution (LR) and Ref images, which enabled texture transfer from different perspectives. To decrease the impact of environmental factors such as resolution, brightness and ambiguity disparities between the LR and Ref images, we designed a feature extraction encoder (FEE) to ensure accuracy in feature extraction in the feature acquisition branch. The experimental results demonstrate that the proposed FCSR achieves significant performance and visual quality compared to state-of-the-art SR methods. Explicitly, when compared with the best method, the average peak signal-to-noise ratio (PSNR) index on the three test sets is improved by 1.0877%, 0.8161%, 1.0296%, respectively, and the structural similarity (SSIM) index on four test sets is improved by 1.4764%, 1.4467%, 0.0882%, and 1.8371%, respectively. Simultaneously, FCSR obtains satisfactory visual details following qualitative evaluation.
Detection of Sargassum from Sentinel Satellite Sensors Using Deep Learning Approach
Authors: Laval Marine , Belmouhcine Abdelbadie , Courtrai Luc , Descloitres Jacques , Salazar-Garibay Adán , Schamberger Léa , Minghelli Audrey , Thibaut Thierry , Dorville René , Mazoyer Camille , Zongo Pascal , Chevalier Cristèle
Published: February 2023

Since 2011, the proliferation of brown macro-algae of the genus Sargassum has considerably increased in the North Tropical Atlantic Sea, all the way from the Gulf of Guinea to the Caribbean Sea and the Gulf of Mexico. The large amount of Sargassum aggregations in that area cause major beaching events, which have a significant impact on the local economy and the environment and are starting to present a real threat to public health. In such a context, it is crucial to collect spatial and temporal data of Sargassum aggregations to understand their dynamics and predict stranding. Lately, indexes based on satellite imagery such as the Maximum Chlorophyll Index (MCI) or the Alternative Floating Algae Index (AFAI), have been developed and used to detect these Sargassum aggregations. However, their accuracy is questionable as they tend to detect various non-Sargassum features. To overcome false positive detection biases encountered by the index-thresholding methods, we developed two new deep learning models specific for Sargassum detection based on an encoder–decoder convolutional neural network (CNN). One was tuned to spectral bands from the multispectral instrument (MSI) onboard Sentinel-2 satellites and the other to the Ocean and Land Colour Instrument (OLCI) onboard Sentinel-3 satellites. This specific new approach outperformed previous generalist deep learning models, such as ErisNet, UNet, and SegNet, in the detection of Sargassum from satellite images with the same training, with an F1-score of 0.88 using MSI images, and 0.76 using OLCI images. Indeed, the proposed CNN considered neighbor pixels, unlike ErisNet, and had fewer reduction levels than UNet and SegNet, allowing filiform objects such as Sargassum aggregations to be detected. Using both spectral and spatial features, it also yielded a better detection performance compared to algal index-based techniques. The CNN method proposed here recognizes new small aggregations that were previously undetected, provides more complete structures, and has a lower false-positive detection rate.