bluuebunny/crossref_metadata_2025 huggingface dataset:
Evolutionary Dynamics of FLC-like MADS-Box Genes in Brassicaceae
Authors: Gramzow Lydia , Sharma Renu , Theißen Günter
Published: September 2023

MADS-box genes encode transcription factors that play important roles in the development and evolution of plants. There are more than a dozen clades of MADS-box genes in angiosperms, of which those with functions in the specification of floral organ identity are especially well-known. From what has been elucidated in the model plant Arabidopsis thaliana, the clade of FLC-like MADS-box genes, comprising FLC-like genes sensu strictu and MAF-like genes, are somewhat special among the MADS-box genes of plants since FLC-like genes, especially MAF-like genes, show unusual evolutionary dynamics, in that they generate clusters of tandemly duplicated genes. Here, we make use of the latest genomic data of Brassicaceae to study this remarkable feature of the FLC-like genes in a phylogenetic context. We have identified all FLC-like genes in the genomes of 29 species of Brassicaceae and reconstructed the phylogeny of these genes employing a Maximum Likelihood method. In addition, we conducted selection analyses using PAML. Our results reveal that there are three major clades of FLC-like genes in Brassicaceae that all evolve under purifying selection but with remarkably different strengths. We confirm that the tandem arrangement of MAF-like genes in the genomes of Brassicaceae resulted in a high rate of duplications and losses. Interestingly, MAF-like genes also seem to be prone to transposition. Considering the role of FLC-like genes sensu lato (s.l.) in the timing of floral transition, we hypothesize that this rapid evolution of the MAF-like genes was a main contributor to the successful adaptation of Brassicaceae to different environments.
Arabidopsis TGA256 Transcription Factors Suppress Salicylic-Acid-Induced Sucrose Starvation
Authors: Bergman Matthew E. , Evans Sonia E. , Kuai Xiahezi , Franks Anya E. , Despres Charles , Phillips Michael A.
Published: September 2023

Salicylic acid (SA) is produced by plants in response to pathogen infection. SA binds the NONEXPRESSOR OF PATHOGENESIS-RELATED GENES (NPR) family of receptors to regulate both positive (NPR1) and negative (NPR3/4) plant immune responses by interacting with the clade II TGACG (TGA) motif-binding transcription factors (TGA2, TGA5, and TGA6). Here, we report that the principal metabolome-level response to SA treatment in Arabidopsis is a reduction in sucrose and other free sugars. We observed nearly identical effects in the tga256 triple mutant, which lacks all clade II TGA transcription factors. The tga256 mutant presents reduced leaf blade development and elongated hypocotyls, roots, and petioles consistent with sucrose starvation. No changes were detected in auxin levels, and mutant seedling growth could be restored to that of wild-type by sucrose supplementation. Although the retrograde signal 2-C-methyl-D-erythritol-2,4-cyclodiphosphate is known to stimulate SA biosynthesis and defense signaling, we detected no negative feedback by SA on this or any other intermediate of the 2-C-methyl-D-erythritol-4-phosphate pathway. Trehalose, a proxy for the sucrose regulator trehalose-6-phosphate (T6P), was highly reduced in tga256, suggesting that defense-related reductions in sugar availability may be controlled by changes in T6P levels. We conclude that the negative regulatory roles of TGA2/5/6 include maintaining sucrose levels in healthy plants. Disruption of TGA2/5/6-NPR3/4 inhibitory complexes by mutation or SA triggers sucrose reductions in Arabidopsis leaves, consistent with the ‘pathogen starvation’ hypothesis. These findings highlight sucrose availability as a mechanism by which TGA2/5/6 balance defense and development.
Combining Multiple Plant Attributes to Reveal Differences in Community Structure in Two Distant Deserts in Central Asia
Authors: Tao Ye , Zhou Xiao-Bing , Yin Ben-Feng , Dimeyeva Liliya , Zhang Jing , Zang Yong-Xin , Zhang Yuan-Ming
Published: September 2023

International interest is growing in biodiversity conservation and sustainable use in drylands. Desert ecosystems across arid Central Asia are severely affected by global change. Understanding the changes in a plant community is an essential prerequisite to revealing the community assembly mechanism, vegetation conservation, and management. The knowledge of large-scale spatial variation in plant community structure in different Central Asian deserts is still limited. In this study, we selected the Taukum (TD, Kazakhstan) and the Gurbantunggut (GD, China) deserts as the research area, with similar latitudes despite being nearly 1000 km apart. Thirteen and 15 sampling plots were set up and thoroughly investigated. The differences in community structure depending on multiple plant attributes (individual level: plant height, canopy diameter, and plant volume, and community level: plant density, total cover, and total volume) were systematically studied. TD had a better overall environmental status than GD. A total of 113 species were found, with 68 and 74 in TD and GD, respectively. The number of species and plant attributes was unequally distributed across different families and functional groups between deserts. The values of several plant attributes, such as ephemerals, annuals, dicotyledons, and shrubs with assimilative branches in GD, were significantly lower than those in TD. The Motyka indices of six plant attributes (26.18–38.61%) were higher between the two deserts than the species similarity index (20.4%), indicating a more robust convergence for plant functional attributes. The community structures in the two deserts represented by different plant attribute matrices demonstrated irregular differentiation patterns in ordination diagrams. The most variance in community structure was attributed to soil and climatic factors, while geographic factors had the smallest proportion. Consequently, the community structures of the two distant deserts were both different and similar to an extent. This resulted from the long-term impacts of heterogeneous environments within the same region. Our knowledge is further deepened by understanding the variation in community structure in different deserts on a large spatial scale. This therefore provides valuable insights into conserving regional biodiversity in Central Asia.
Increased Plasticity in Invasive Populations of a Globally Invasive Cactus
Authors: Tesfay Yohannes B. , Blaschke Annika , Ashley Nathan , Portillo Liberato , Scalisi Alessio , Adli Benziane , Kreyling Juergen
Published: September 2023

Biological invasions pose global threats to biodiversity and ecosystem functions. Invasive species often display a high degree of phenotypic plasticity, enabling them to adapt to new environments. This study examines plasticity to water stress in native and invasive Opuntia ficus-indica populations, a prevalent invader in arid and semi-arid ecosystems. Through controlled greenhouse experiments, we evaluated three native and nine invasive populations. While all plants survived the dry treatment, natives exhibited lower plasticity to high water availability with only a 36% aboveground biomass increase compared to the invasives with a greater increase of 94%. In terms of belowground biomass, there was no significant response to increased water availability for native populations, but plants from the invasive populations showed a 75% increase from the dry to the wet treatment. Enhanced phenotypic plasticity observed in invasive populations of O. ficus-indica is likely a significant driver of their success and invasiveness across different regions, particularly with a clear environmental preference towards less arid conditions. Climate change is expected to amplify the invasion success due to the expansion of arid areas and desertification. Opuntia ficus-indica adapts to diverse environments, survives dry spells, and grows rapidly in times of high-water supply, making it a candidate for increased invasion potential with climate change.
Current Advances in the Biosynthesis, Metabolism, and Transcriptional Regulation of α-Tomatine in Tomato
Authors: Liu Yuanyuan , Hu Hanru , Yang Rujia , Zhu Zhujun , Cheng Kejun
Published: September 2023

Steroid glycoalkaloids (SGAs) are a class of cholesterol-derived metabolites commonly found in the Solanaceae plants. α-Tomatine, a well-known bitter-tasting compound, is the major SGA in tomato, accumulating extensively in all plant tissues, particularly in the leaves and immature green fruits. α-Tomatine exhibits diverse biological activities that contribute to plant defense against pathogens and herbivores, as well as conferring certain medicinal benefits for human health. This review summarizes the current knowledge on α-tomatine, including its molecular chemical structure, physical and chemical properties, biosynthetic and metabolic pathways, and transcriptional regulatory mechanisms. Moreover, potential future research directions and applications of α-tomatine are also discussed.
Complete Genome Characterization of Penicillimonavirus gammaplasmoparae, a Bipartite Member of the Family Mymonaviridae
Authors: Morán Félix , Olmos Antonio , Candresse Thierry , Ruiz-García Ana Belén
Published: September 2023

In this study, we identified Plasmopara-viticola-lesion-associated mononegaambi virus 3 (recently classified as Penicillimonavirus gammaplasmoparae), a fungi-associated mymonavirus, in grapevine plants showing an unusual upward curling symptomatology on the leaves and premature decline. Mymonaviridae is a family comprising nine genera of negative-sense single-stranded RNA viruses infecting filamentous fungi, although few of them have been associated with oomycetes, plants, and insects. Although the first mymonavirus genome description was reported a decade ago, the genome organization of several genera in the family, including the genus Penicillimonavirus, has remained unclear to date. We have determined the complete genome of P. gammaplasmoparae, which represents the first complete genomic sequence for this genus. Moreover, we provide strong evidence that P. gammaplasmoparae genome is bipartite and comprises two RNA molecules of around 6150 and 4560 nt. Our results indicate that the grapevine powdery mildew pathogen, Erysiphe necator, was also present in the analyzed plants and suggest P. gammaplasmoparae could be infecting this fungus. However, whether the fungus and/or the mycovirus are associated with the symptomatology that initially prompted these efforts remains to be determined.
Improving the Pervaporation Performance of PDMS Membranes for Trichloroethylene by Incorporating Silane-Modified ZSM-5 Zeolite
Authors: Song Xiaosan , Song Xichen , Zhang Yue , Fan Jishuo
Published: September 2023

The hydrophobic nature of inorganic zeolite particles plays a crucial role in the efficacy of mixed matrix membranes (MMMs) for the separation of trichloroethylene (TCE) through pervaporation. This study presents a novel approach to further augment the hydrophobicity of ZSM-5. The ZSM-5 zeolite molecular sieve was subjected to modification using three different silane coupling agents, namely, n-octyltriethoxysilane (OTES), γ-methacryloxypropyltrimethoxysilane (KH-570), and γ-aminopropyltriethoxysilane (KH-550). The water contact angles of the resulting OTES@ZSM-5, KH-570@ZSM-5, and KH-550@ZSM-5 particles exhibited significant increases from 97.2° to 112.8°, 109.1°, and 102.7°, respectively, thereby indicating a notable enhancement in hydrophobicity. Subsequently, mixed matrix membranes (MMMs) were fabricated by incorporating the aforementioned silane-modified ZSM-5 particles into polydimethylsiloxane (PDMS), leading to a considerable improvement in the adsorption selectivity of these membranes towards trichloroethylene (TCE). The findings indicate that the PDMS membrane with a 20 wt.% OTES@ZSM-5 particle loading exhibits superior pervaporation performance. When subjected to a temperature of 30 °C, flow rate of 100 mL/min, and vacuum of 30 Kpa, the separation factor and total flux of a 3 × 10−7 wt.% TCE solution reach 328 and 155 gm−2·h−1, respectively. In comparison to the unmodified ZSM-5/PDMS membrane, the separation factor demonstrates a 41% increase, while the TCE flux experiences a 6% increase. Consequently, this approach effectively enhances the pervaporation separation capabilities of the PDMS membrane for TCE.
Thermoelectric Properties of One-Pot Hydrothermally Synthesized Solution-Processable PEDOT:PSS/MWCNT Composite Materials
Authors: Li Haibin , Zhou Shisheng , Han Shanxiang , Luo Rubai , Hu Jingbo , Du Bin , Yang Kenan , Bao Yizhi , Jia Junjie , Zhang Xuemei
Published: September 2023

The combination of organic and inorganic materials has been considered an effective solution for achieving ambient thermoelectric energy harvesting and has been developing rapidly. Here, PEDOT:PSS/MWCNT (PPM) composite hydrogels were synthesized using the self-assembled gelation process of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) and the interaction between PEDOT:PSS and multi-walled carbon nanotubes (MWCNTs) without the addition of any surfactant. After immersion in dimethyl sulfoxide and freeze-drying, the hydrogel is easily dispersed in water and used as a direct ink writing (DIW) 3D printing ink. At room temperature, the PPM-20 printed film with 20 wt% MWCNT solids achieved a maximum power factor of 7.37 μW m−1 K−2 and maintained stable thermoelectric properties during repeated bending cycles. On this basis, a thermoelectric generator (TEG) consisting of five legs was printed, which could be produced to generate an open circuit voltage of 6.4 mV and a maximum output power of 40.48 nW at a temperature gradient of 50 K, confirming its great potential for application in high-performance flexible organic/inorganic thermoelectric materials.
Enhanced Mechanical Properties of PVA Hydrogel by Low-Temperature Segment Self-Assembly vs. Freeze–Thaw Cycles
Authors: Wu Fei , Gao Jianfeng , Xiang Yang , Yang Jianming
Published: September 2023

The rapid and effective fabrication of polyvinyl alcohol (PVA) hydrogels with good mechanical properties is of great significance yet remains a huge challenge. The preparation of PVA hydrogels via the conventional cyclic freeze–thaw method is intricate and time-intensive. In this study, a pioneering approach involving the utilization of low-temperature continuous freezing is introduced to produce a novel PVA-ethylene glycol (EG) gel. Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometry (XRD) and scanning electron microscopy (SEM) confirm that with the assistance of EG, PVA molecular chains can self-assemble to generate an abundance of microcrystalline domains at low temperatures, thus improving the mechanical properties of PVA-EG gel. Remarkably, when the mass ratio of H2O/EG is 4:6, the gel’s maximum tensile strength can reach 2.5 MPa, which is much higher than that of PVA gels prepared via the freeze–thaw method. The preparation process of PVA-EG gel is simple, and its properties are excellent, which will promote the wide application of PVA tough gel in many fields.
Conductive Polymers and Their Nanocomposites: Application Features in Biosensors and Biofuel Cells
Authors: Kuznetsova Lyubov S. , Arlyapov Vyacheslav A. , Plekhanova Yulia V. , Tarasov Sergei E. , Kharkova Anna S. , Saverina Evgeniya A. , Reshetilov Anatoly N.
Published: September 2023

Conductive polymers and their composites are excellent materials for coupling biological materials and electrodes in bioelectrochemical systems. It is assumed that their relevance and introduction to the field of bioelectrochemical devices will only grow due to their tunable conductivity, easy modification, and biocompatibility. This review analyzes the main trends and trends in the development of the methodology for the application of conductive polymers and their use in biosensors and biofuel elements, as well as describes their future prospects. Approaches to the synthesis of such materials and the peculiarities of obtaining their nanocomposites are presented. Special emphasis is placed on the features of the interfaces of such materials with biological objects.
Bamboo Pulp Toughening Poly (Lactic Acid) Composite Using Reactive Epoxy Resin
Authors: Kiattipornpithak Krittameth , Rachtanapun Pornchai , Thanakkasaranee Sarinthip , Jantrawut Pensak , Ruksiriwanich Warintorn , Sommano Sarana Rose , Leksawasdi Noppol , Kittikorn Thorsak , Jantanasakulwong Kittisak
Published: September 2023

A novel poly (lactic acid) (PLA) composite with excellent mechanical properties, toughness, thermal stability, and water resistance was developed using a reactive melt-blending technique. PLA was melt mixed with epoxy resin (EPOXY) and bamboo pulp (PULP) to improve its reaction and mechanical properties. FTIR analysis confirmed the successful reaction of the PLA/EPOXY/PULP composites; the epoxy groups of EPOXY reacted with the –COOH groups of PLA and the –OH groups of PULP. The PLA/EPOXY/PULP5 composite showed a high tensile strength (67 MPa) and high toughness of 762 folding cycles, whereas the highest tensile strength was 77 MPa in the PLA/EPOXY5/PULP20 sample. SEM images presented a gap between the PLA and PULP; gap size decreased with the addition of EPOXY. The Tg of the PLA decreased with the EPOXY plasticizer effect, whereas the Tm did not significantly change. PULP induced crystallinity and increased Vicat softening of the PLA/PULP and PLA/EPOXY/PULP composites. The EPOXY reaction of the PLA/PULP composites improved their tensile properties, toughness, thermal stability, and water resistance.
Analytical Pyrolysis of Pinus radiata and Eucalyptus globulus: Effects of Microwave Pretreatment on Pyrolytic Vapours Composition
Authors: Venegas-Vásconez Diego , Arteaga-Pérez Luis E. , Aguayo María Graciela , Romero-Carrillo Romina , Guerrero Víctor H. , Tipanluisa-Sarchi Luis , Alejandro-Martín Serguei
Published: September 2023

Pinus radiata (PR) and Eucalyptus globulus (EG) are the most planted species in Chile. This research aims to evaluate the pyrolysis behaviour of PR and EG from the Bío Bío region in Chile. Biomass samples were subjected to microwave pretreatment considering power (259, 462, 595, and 700 W) and time (1, 2, 3, and 5 min). The maximum temperature reached was 147.69 °C for PR and 130.71 °C for EG in the 700 W-5 min condition, which caused the rearrangement of the cellulose crystalline chains through vibration and an increase in the internal energy of the biomass and the decomposition of lignin due to reaching its glass transition temperature. Thermogravimetric analysis revealed an activation energy (Ea) reduction from 201.71 to 174.91 kJ·mol−1 in PR and from 174.80 to 158.51 kJ·mol−1 in EG, compared to the untreated condition (WOT) for the 700 W-5 min condition, which indicates that microwave pretreatment improves the activity of the components and the decomposition of structural compounds for subsequent pyrolysis. Functional groups were identified by Fourier transform infrared spectroscopy (FTIR). A decrease in oxygenated compounds such as acids (from 21.97 to 17.34% w·w−1 and from 27.72 to 24.13% w·w−1) and phenols (from 34.41 to 31.95% w·w−1 and from 21.73 to 20.24% w·w−1) in PR and EG, respectively, was observed in comparison to the WOT for the 700 W-5 min condition, after analytical pyrolysis. Such results demonstrate the positive influence of the pretreatment on the reduction in oxygenated compounds obtained from biomass pyrolysis.
An Overview of Polymer Composite Films for Antibacterial Display Coatings and Sensor Applications
Authors: Ippili Swathi , Jung Jang-Su , Thomas Alphi Maria , Vuong Van-Hoang , Lee Jeong-Min , Sha Mizaj Shabil , Sadasivuni Kishor Kumar , Jella Venkatraju , Yoon Soon-Gil
Published: September 2023

The escalating presence of pathogenic microbes has spurred a heightened interest in antimicrobial polymer composites tailored for hygiene applications. These innovative composites ingeniously incorporate potent antimicrobial agents such as metals, metal oxides, and carbon derivatives. This integration equips them with the unique ability to offer robust and persistent protection against a diverse array of pathogens. By effectively countering the challenges posed by microbial contamination, these pioneering composites hold the potential to create safer environments and contribute to the advancement of public health on a substantial scale. This review discusses the recent progress of antibacterial polymer composite films with the inclusion of metals, metal oxides, and carbon derivatives, highlighting their antimicrobial activity against various pathogenic microorganisms. Furthermore, the review summarizes the recent developments in antibacterial polymer composites for display coatings, sensors, and multifunctional applications. Through a comprehensive examination of various research studies, this review aims to provide valuable insights into the design, performance, and real-time applications of these smart antimicrobial coatings for interactive devices, thus enhancing their overall user experience and safety. It concludes with an outlook on the future perspectives and challenges of antimicrobial polymer composites and their potential applications across diverse fields.
Comparison Adsorption of Cd (II) onto Lignin and Polysaccharide-Based Polymers
Authors: Ungureanu Elena , Fortună Maria E. , Țopa Denis C. , Brezuleanu Carmen O. , Ungureanu Vlad I. , Chiruță Ciprian , Rotaru Razvan , Tofanica Bogdan M. , Popa Valentin I. , Jităreanu Doina C.
Published: September 2023

Given the predominantly negative impact of heavy metals on living organisms, the present study proposed to evaluate the adsorption performances under static conditions of Cd (II) from aqueous solutions on unmodified Sarkanda grass lignin compared to the adsorption performances of polysaccharide polymers chemically functionalized, obtained by synthesis and in their native state, but which, although effective, have a cost price that does not allow for large-scale expansion. To improve the retention of Cd (II) on this aromatic component of the biomass resulting from the processing of lignocellulosic materials, different experimental conditions (pH, concentration, dose and contact time) were followed. The Freundlich and Langmuir isotherms were used to describe the equilibrium conditions. Adsorption kinetics were assessed using the Lagergren I and Ho and McKay II kinetic models, furnishing informative insights into the process mechanism. Lignin adsorption capacity was also analyzed by performing biological tests on tomato seeds (Lypercosium esculentum), since heavy metals are known to be a stress factor for seeds by disturbing the osmotic equilibrium. Through the prism of the investigated parameters and under precisely established experimental conditions, unmodified Sarkanda grass lignin—an aromatic biopolymer—can be recommended as a promising adsorbent for the retention of Cd (II) from aqueous solutions, successfully replacing polysaccharide, especially cellulose-based polymers.
Predicting Critical Loads in Fused Deposition Modeling Graphene-Reinforced PLA Plates Containing Notches Using the Point Method
Authors: Cicero Sergio , Sánchez Marcos , Arrieta Sergio
Published: September 2023

The use of 3D-printed composites in structural applications beyond current prototyping applications requires the definition of safe and robust methodologies for the determination of critical loads. Taking into account that notches (corners, holes, grooves, etc.) are unavoidable in structural components, the presence of these types of stress risers affects the corresponding load-carrying capacity. This work applies the point method (PM) to the estimation of the critical (fracture) loads of graphene-reinforced polylactic acid (PLA-Gr) plates obtained via fused deposition modeling (FDM) with a fixed raster orientation at 45/−45. Additionally, the plates contain three different notch types (U-notches, V-notches, and circular holes) and comprise various thicknesses (from 5 mm up to 20 mm) and ratios of notch length to plate width (a/W= 0.25 and a/W = 0.50). The comparison between the obtained experimental critical loads and the corresponding estimations derived from the application of the PM reveals that this approach generates reasonable accuracy in this particular material that is comparable to the accuracy obtained in other structural materials obtained via traditional manufacturing processes.
Effect of Thermal Aging on Mechanical Properties and Morphology of GF/PBT Composites
Authors: Xu Xiuqi , Deng Jiangang , Nie Siyu , Lan Zhenbo , Xu Zhuolin
Published: September 2023

The effects of thermal aging at 85~145 °C in air on the tensile and flexural mechanical properties of 20% glass fiber (GF)-reinforced commercial grade polybutylene terephthalate (PBT) composites were studied. The results showed that as the aging temperature increased, the tensile and flexural strength of the GF/PBT composites significantly decreased. However, the elastic modulus of the composites was almost independent of aging. As the aging temperature increased, the separation between GF and the PBT matrix became more pronounced, and the fibers exposed on the surface of the matrix became clearer and smoother, indicating a decrease in interfacial adhesion between the PBT matrix and GF. The reason for this decrease in strength and brittle fracture of composites is the interface damage between the GF and PBT matrix caused by the difference in their thermal expansion coefficients during thermal aging.
A Molecular Dynamics Simulation Study on Enhancement of Mechanical and Tribological Properties of Nitrile—Butadiene Rubber with Varied Contents of Acrylonitrile
Authors: Yuan Quan , Li Yunlong , Wang Shijie , He Enqiu , Yang Bin , Nie Rui
Published: September 2023

The molecular models of nitrile–butadiene rubber (NBR) with varied contents of acrylonitrile (ACN) were developed and investigated to provide an understanding of the enhancement mechanisms of ACN. The investigation was conducted using molecular dynamics (MD) simulations to calculate and predict the mechanical and tribological properties of NBR through the constant strain method and the shearing model. The MD simulation results showed that the mechanical properties of NBR showed an increasing trend until the content of ACN reached 40%. The mechanism to enhance the strength of the rubber by ACN was investigated and analyzed by assessing the binding energy, radius of gyration, mean square displacement, and free volume. The abrasion rate (AR) of NBR was calculated using Fe-NBR-Fe models during the friction processes. The wear results of atomistic simulations indicated that the NBR with 40% ACN content had the best tribological properties due to the synergy among appropriate polarity, rigidity, and chain length of the NBR molecules. In addition, the random forest regression model of predicted AR, based on the dataset of feature parameters extracted by the MD models, was developed to obtain the variable importance for identifying the highly correlated parameters of AR. The torsion–bend–bend energy was obtained and used to successfully predict the AR trend on the new NBR models with other acrylonitrile contents.
Functional Properties of Chitosan Oligomers Obtained by Enzymatic Hydrolysis
Authors: Kulig Dominika , Król-Kilińska Żaneta , Bobak Łukasz , Żarowska Barbara , Jarmoluk Andrzej , Zimoch-Korzycka Anna
Published: September 2023

The aims of this study were to obtain chitooligosaccharides (COS) from chitosan (CH) with improved functional properties and comparison of the use of two different enzymes: commercial cellulase (CL) and the dedicated enzyme chitosanase (CS). After enzymatic reaction, chitosan oligomers (NFs) were isolated by methanol into two fractions: precipitate (HMF) and supernatant (LMF). The occurrence of a hydrolysis reaction was confirmed by an increased reducing sugar content and viscosity reduction of chitosan oligomers. CPMAS 13C NMR analysis confirmed the dissimilar cleavage mechanism of the enzymes used. LMF and NF fractions were characterised by improved solubility in water (94.56%) compared to the HMF and CH samples (70.64%). Thermogravimetric analysis (TGA) showed that the HMF decomposed in two-stage process while CH, NF, and LMF decomposed in a three-stage process. The greatest mass loss of LMF samples (58.35%) suggests their sensitivity to high-temperature treatments. COS were a mixture of DP (degrees of polymerisation) from 3 to 18 hetero-chitooligomers, with an average Mw of <3 kDa. CL consisted of more low-DP products (DP 3–7) than COS made with CS. LMF characterised by DP~2 showed lower DPPH radical scavenging activity than HMF and NF with DP 3–7. The ability to reduce Escherichia coli increased in the given order: LMF > NF > HMF > CH.
Dimethylformamide Impurities as Propylene Polymerization Inhibitor
Authors: Hernández-Fernández Joaquín , González-Cuello Rafael , Ortega-Toro Rodrigo
Published: September 2023

This research study examined how the use of dimethylformamide (DMF) as an inhibitor affects the propylene polymerization process when using a Ziegler–Natta catalyst. Several experiments were carried out using TiCl4/MgCl2 as a catalyst, aluminum trialkyl as a cocatalyst, and different amounts of DMF. Then, we analyzed how DMF influences other aspects of the process, such as catalyst activity, molecular weight, and the number of branches in the polymer chains obtained, using experimental and computational methods. The results revealed that as the DMF/Ti ratio increases, the catalyst activity decreases. From a concentration of 5.11 ppm of DMF, a decrease in catalyst activity was observed, ranging from 45 TM/Kg to 44 TM/Kg. When the DMF concentration was increased to 40.23 ppm, the catalyst activity decreased to 43 TM/Kg, and with 75.32 ppm, it dropped even further to 39 TM/Kg. The highest concentration of DMF evaluated, 89.92 ppm, resulted in a catalyst productivity of 36.5 TM/Kg and lost productivity of 22%. In addition, significant changes in the polymer’s melt flow index (MFI) were noted as the DMF concentration increased. When 89.92 ppm of DMF was added, the MFI loss was 75%, indicating a higher flowability of the polymer. In this study, it was found that dimethylformamide (DMF) exhibits a strong affinity for the titanium center of a Ziegler–Natta (ZN) catalyst, with an adsorption energy (Ead) of approximately −46.157 kcal/mol, indicating a robust interaction. This affinity is significantly higher compared to propylene, which has an Ead of approximately −5.2 kcal/mol. The study also revealed that the energy gap between the highest occupied molecular orbital (HOMO) of DMF and the lowest unoccupied molecular orbital (SOMO) of the Ziegler–Natta (ZN) catalyst is energetically favorable, with a value of approximately 0.311 eV.
Pyrolysis Behavior and Kinetics of Typical Crop Straw in Henan Province at Different Heating Rates
Authors: Hu Po , Hou Chenghao , Lan Xinyu , Sheng Honghao
Published: September 2023

Straw, which is characterized by its low cost, large quantity, and rich supply of biomass energy, is often converted into energy that can be utilized in industrial production through pyrolysis technology. This paper examines the pyrolysis experiments of four kinds of straw (rice, wheat, peanut, and corn) from the Henan Province of China, conducted in an air environment with varying temperature-rise rates. Based on the experimental results, an analysis was conducted on the effect of the rate of temperature rise on the degree of straw pyrolysis and the pyrolysis characteristics of each type of straw. The activation energies of the pyrolysis reactions were calculated utilizing the Kissinger–Akahira–Sunose (KAS), Flynn–Wall–Ozawa (FWO), and Starink methods. It was concluded that the pyrolysis process of all four types of straw could roughly be classified into three stages: dehydration and drying stage, volatile release stage, and carbonization stage. Among the four types of straw evaluated, rice straw exhibited the most favorable combustion performance, while wheat straw demonstrated the best pyrolysis effect. Increasing the heating rate resulted in a pronounced thermal hysteresis effect during the straw’s pyrolysis, as evidenced by the TG and DTG curves shifting toward higher temperatures. The reaction speed increased as the heating rate increased, and the amount of residual carbon displayed an upward trend.
Exploration of Pyrolysis Behaviors of Waste Plastics (Polypropylene Plastic/Polyethylene Plastic/Polystyrene Plastic): Macro-Thermal Kinetics and Micro-Pyrolysis Mechanism
Authors: Xuan Weiwei , Yan Shiying , Dong Yanwu
Published: September 2023

Pyrolysis is a promising technology used to recycle both the energy and chemicals in plastics. Three types of plastics, polyethylene plastic (PE), polypropylene plastic (PP) and polystyrene plastic (PS) were investigated using thermogravimetry–mass spectrometry (TG–MS) and reactive force field molecular dynamics (ReaxFF-MD) simulation. The thermogravimetric analysis showed that all three plastics lost weight during the pyrolysis in one step. The thermal decomposition stability is PS < PP < PE. The activation energies and reaction mechanism function of the three plastics were determined by the Kissinger and CR methods. Meanwhile, the ReaxFF-MD combined with density functional theory (DFT) was used to calculate the kinetics, as well as explore the pyrolysis mechanism. The calculated kinetic results agree well with the experimental methods. The common pyrolysis reaction process follows the dissociation sequence of the polymer to polymeric monomer and, then, to the gas molecules. Based on the bond length between the monomers and the bond dissociation energy for different plastics, the required energy for polymer dissociation is PS < PP < PE, which microscopically explains the macro-activation energy sequence and thermal stability. Moreover, due to the retention of aromatic rings in its monomers, PS almost completely converts into oil.
Dynamic Modeling and Parameter Identification of Double Casing Joints for Aircraft Fuel Pipelines
Authors: Quan Lingxiao , Fu Chen , Yao Renyi , Guo Changhong
Published: September 2023

Double casing joints are flexible pipe joints used for connecting aircraft fuel pipelines, which can compensate for the displacement and corner of the connected pipes and have complex mechanical characteristics. However, it is difficult to use sensors to directly measure the mechanical connection parameters of flexible joints. In this paper, we construct a coupling dynamics model and parameter identification of a double casing joint. Firstly, we analyze the structure and working principle of double-layer casing joints and establish the dynamics model of a single-layer flexible joint based on the transfer matrix method. Then, we deduce the coupling matrix of the inner and outer pipeline according to the deformation coordination conditions combined with matrix dimension extension. We establish the coupling dynamics model of flow–solid coupling of double casing joints. Furthermore, parameters such as equivalent stiffness and damping of each motion of the double casing joint in the casing unit are identified using the force-state mapping (FSM) method, and an analytical solution in the frequency domain under hammering excitation is given by the dynamics model. Finally, the dynamics test bench of the double casing joint for aircraft fuel is set up, and the free mode test of the double casing joint assembly is carried out. The results show that under free boundary hammering excitation, the theoretical and experimental frequency-domain response results are well matched, both obtaining seven main resonance peaks, and the maximum error is 9.45%, which shows the validity of the pipeline dynamics modeling method with a double casing joint.
Antibacterial Activities of Oral Care Products Containing Natural Plant Extracts from the Thai Highlands against Staphylococcus aureus: Evaluation and Satisfaction Studies
Authors: Chaiwaree Saranya , Srilai Kannika , Kheawfu Kantaporn , Thammasit Patcharin
Published: September 2023

In this research, we aimed to assess antibacterial activity and develop oral care products from three natural plant extracts from the Thai highlands. The plants, including Camellia sinensis var. assamica, Zanthozylum limonella Alston, and Acorus calamus L., were extracted using two traditional extraction techniques: maceration and hydrodistillation methods. The extracts were characterized by percentage yield, total phenolic, and total flavonoid contents. Antibacterial activity against Staphylococcus aureus, which play a role in oral health and disease, was investigated. C. sinensis var. assamica extract had the highest content of phenolic acid (38.15 ± 4.12 mg GAE/g extract) and flavonoids (44.91 ± 2.76 mg QE/g extract). Interestingly, a combination of C. sinensis with Z. limonella and A. calamus provides a greater inhibitory effect against S. aureus. Furthermore, oral care products were prepared as a natural product mixture in two preparations: (i) oral ulcers gel and (ii) oral spray. Apart from antibacterial efficiency, volunteer satisfaction after the usage of oral care products containing traditional plant extracts was investigated via organoleptic evaluation. The findings of the volunteer surveys indicated positive feedback for both oral care products with high satisfaction levels. Hence, these oral care products could potentially be natural antimicrobial agents and can be further developed and applied for oral applications in the pharmaceutical and cosmetic industries.
Novel Control Technology for Reducing Output Power Harmonics of Standalone Solar Power Generation Systems
Authors: Liu Hwa-Dong , Lin Jhen-Ting , Lin Xin-Wen , Lin Chang-Hua , Farooqui Shoeb-Azam
Published: September 2023

This study presents a standalone solar power system that incorporates a photovoltaic (PV) module, a boost converter, an H-bridge inverter, a low-pass filter (LPF), and a microcontroller unit (MCU). A novel cake sweetness maximum power point tracking (CS MPPT) algorithm and adjustable frequency and duty cycle (AFDC) control strategy has been proposed and efficiently applied to the solar power system for optimizing the system efficiency and output power quality. The experimental results show that the proposed CS MPPT algorithm achieves an efficiency of 99% under both the uniform irradiance conditions (UIC) and partial shading conditions (PSC). Subsequently, the AFDC control strategy is applied to the H-bridge inverter which improves the output AC voltage and AC current and thereby improving the power quality. The system ensures a stable 110 Vrms/60 Hz AC output voltage with only 2% total voltage harmonic distortion of voltage (THDv), and produces a high-quality output voltage with reduced LPF volume and better economic benefits. The comparative analysis demonstrates that the characteristics and the performances of the CS MPPT algorithm in combination with the AFDC control strategy is better than the existing several maximum power point tracking (MPPT) techniques and inverter control strategies. The research output affirms the potential of the proposed solar power system to fulfill the actual daily needs of electricity by harnessing the maximum power from PV modules.
Biochemical Characterization and Fuel Properties of Endemic Taurus Flowering Ash (Fraxinus ornus subsp. cilicica) Bark from Turkey
Authors: Şen Ali Umut , Simões Rita , Yücedağ Cengiz , Miranda Isabel , Fernandes Ângela , Pereira Helena
Published: September 2023

Taurus flowering ash (Fraxinus ornus subsp. cilicica) is an endemic tree species in Turkey. The bark of the species was characterized for summative chemical composition, the monomeric composition of polysaccharides, phenolic content, in vitro and ex vivo antioxidant properties of hydrophilic extracts, the composition of lipophilic extractives and suberin, and thermal degradation. The bark has an elevated ash content (17%), primarily composed of calcium, and a noteworthy extractive content (38.9%), predominantly of hydrophilic compounds. The antioxidant activity of the bark extracts is moderate, with an IC50 value of 40 μg/mL and an EC50 value of 230 μg/mL by DPPH and TBARS methods. The lipophilic extractives principally contain fatty acids and diterpenoids. The suberin content is low (1%) and composed primarily of ω-hydroxy acids with 9,10,18 trihydroxyoctadecanoic acid as the major suberin monomer. The lignin content is low (9.8%), and polysaccharides represent 33%. The ignition temperature of the bark is 190 °C, the burnout temperature is 653 °C, and the activation energy in combustion is 29 kJ mol−1. A biorefinery concept was developed considering the bark’s chemical and thermal characteristics to convert approximately 90% of the bark mass into valuable chemicals, extracts, functional materials, and additives.
Discrete Meta-Simulation of Silage Based on RSM and GA-BP-GA Optimization Parameter Calibration
Authors: Li Gonghao , Ma Juan , Tian Xiang , Zhao Chao , An Shiguan , Guo Rui , Feng Bin , Zhang Jie
Published: September 2023

The EDEM software (Altair EDEM 2022.0 professional version 8.0.0) was used to create a discrete element model of silage to address the lack of silage evidence parameters and contact parameters between silage and conveying equipment when using the discrete element method to simulate and analyze crucial aspects of silage conveying and feeding. Physical tests and simulations were used to calibrate the significant parameters, and the silage stacking angle obtained from simulation and tests was then validated. The response value of the stacking angle (38.65°) obtained from the physical examination was used as the response value. The response surface (RSM) finding and the GA finding based on the genetic algorithm (GA) artificial neural network (BP) model were used to compare the significance parameters. The PB and steepest climb tests were used to screen the significant factors. Results indicate that the static friction coefficient between silage and silage, the rolling friction coefficient between silage and silage, and the static friction coefficient between silage and the steel body are significant factors affecting the stacking angle of numerical simulation; the parameter optimization effect of GA-BP-GA is superior to that of RSM; the optimal parameter combinations are as follows: 0.495, 0.194, and 0.420, respectively, and the simulated stacking angle is 39.1510°, which matches the empirical test result. The relative error between the simulated and stacking angles derived from the physical test was 1.3%. The results demonstrate that the silage model is reliable within the parameters derived from the calibration, and that the calibrated parameters can be used in other discrete element simulation studies of silage.
Minimally Invasive versus Conventional Approaches in Total Hip Arthroplasty: A Systematic Review and Meta-Analysis of 47 Randomized Controlled Trials
Authors: Ramadanov Nikolai , Marinova-Kichikova Polina , Hable Robert , Dimitrov Dobromir
Published: September 2023

Background: Recent meta-analyses have shown indifferent results between minimally invasive (MI) and conventional approach (CA) total hip arthroplasty (THA), not including the superior MI approach SuperPATH. The aim was to compare the surgical, functional and radiological outcomes and postoperative complications of MI THA, including SuperPATH, with CA THA in patients with hip disease or femoral neck fracture. Methods: PubMed, CNKI, The Cochrane Library, clinical trials, CINAHL and Embase were searched for randomized controlled trials (RCTs) comparing MI THA and CA THA up to 31 July 2023. Mean differences (MDs) with 95% confidence intervals (CIs) were calculated for continuous outcomes and odds ratios (ORs) with 95% CIs were calculated for dichotomous outcomes using a common effect/random effects model. The random effects model was used to present the results. Heterogeneity was assessed using the Cochrane Q test and the Higgins I2 test. Results: A total of 47 RCTs with 4086 THAs in 4063 patients were included in our meta-analysis. MI THA showed better results than CA THA in 8 of 18 outcome parameters studied. MI THA showed a higher Harris Hip Score (HHS) than CA THA at 0–1.5, 3, 6 and ≥12 months postoperatively (p < 0.01; p = 0.02; p = 0.01; p = 0.01). MI THA showed an indifferent overall postoperative complication risk compared to CA THA (p = 0.61). Acetabular positioning angles were within the safe zone in all approaches. Conclusions: The results of the meta-analysis suggest that MI THA has several advantages over CA THA in terms of short-term surgical and functional outcomes, with equal postoperative complication rates. We cannot recommend a change in surgical approach based on our results, as the differences between the investigated approaches did not reach minimal clinically important differences. Level of evidence I: a systematic review of all relevant randomized controlled trials.
A Local Pilgrimage in the Context of the COVID-19 Pandemic: The Case of Our Lady of the Snows in Kukljica, Croatia
Authors: Pojatina Adriana Branka
Published: September 2023

This article is based on ethnographic research conducted in Kukljica on the island of Ugljan (Croatia) beginning in August 2020 for the purpose of the author’s doctoral thesis. The complexity of initiating research in a new locality was further burdened by the pandemic, which inevitably affected the outset of fieldwork in this case. This article is thus intended to demonstrate how ethnographic research was conducted during the COVID-19 pandemic and present an image of “corona reality“ in the context of a local-scale pilgrimage. Through the example of the author’s research in Kukljica, this article shows how the research community adapted to the prevailing situation, which was characterized by restrictions and the introduction of new rules, and demonstrates the continuity of local religious practice in a global crisis during the COVID-19 pandemic.
The Anointed Steward: A Critical Review of Western Christian and Secular Steward Leadership Literature
Authors: Tolbert Carl Lee
Published: September 2023

This paper critically examines the literature associated with steward leadership from the Western Christian and secular perspectives. The motivation is to offer a better understanding for individuals endeavoring to apply the emerging steward leadership paradigm to organizations. The critical review process was determined as the best method to cultivate direct and indirect literature across multiple diverse domains. Over 1000 sources were examined, resulting in over 400 coded themes creating the foundation of the critical review. During the critical coding appraisal of the literature, four concentrated themes were identified: “steward” and “servant” as leadership modalities, and “mission” and “stakeholder” from a stewardship governance perspective. The identified themes led to the natural creation of a conceptual filter tool, allowing the literature to be more easily identified and sorted based on organizational utility. The literature’s narrative reflection and the normative filtering of the themes identified two key summary details. The first detail was the notion of steward and servant leadership being inescapably connected and inseparable. The second detail was that stewardship governance is a plausible remedy for agency, but agency controls are still needed based on contingency.
Metaphorical Metaphysics in the Dao De Jing
Authors: Fox Alan
Published: September 2023

Many readers of the Dao De Jing have identified an ontology associated with the text. In such ontological readings, the term dao 道 is taken to refer to some type of monolithic, eternal, abstract fundamental reality. They generally point to certain chapters of the text as supporting this interpretation. The implication seems virtually theological, at least in the impersonal “Advaitic Brahman” sense. However, if we carefully examine the passages to which such proponents refer as evidence of this position, it becomes clear that these chapters are metaphorical rather than metaphysical. I propose to examine several of these chapters to clarify the tentative and rhetorical nature of their expression.