bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of Novel Trisubstituted Olefin-Type Probe Molecules Containing N-Heterocycles and Their Application in Detection of Malononitrile
Authors: Chen Zhao-Hua , Yu Shi-Wei , Xu Wen-Jin , Li Miao-Xin , Zeng Yong , Deng Si-Wei , Lin Jian-Yun , Wang Zhao-Yang
Published: April 2024

Recently, the construction of the trisubstituted olefin-type probe molecules has elicited the attention of many researchers. However, the synthesis of the trisubstituted olefin-type probes containing two N-heterocycles simultaneously has been rarely reported. In this study, starting from the inexpensive mucobromic acid 1 and N-heterocyclic compound 2, we first utilized a simple one-step reaction to synthesize a series of trisubstituted olefin-type compounds 3 simultaneously bearing with the structure of two N-heterocyclic rings in the absence of transition metal catalysts with a yield of 62–86%. The optimal reaction conditions were systematically explored, and the structure of the obtained compounds 3 were well characterized with 1H NMR, 13C NMR, X-ray single-crystal and HR-MS. The preliminary observation showed that, in the presence of base, mucobromic acid 1 reacts as its ring-opening structure, and the successive nucleophilic substitution reaction and Michael addition reaction can generate the target product 3. Considering that the aldehyde group in the molecular structure of the trisubstituted olefin-type compounds 3 may react with malononitrile, we carried out some relevant investigations so as to realize the visual detection of malononitrile. Interestingly, among the products, compounds 3a–3c can be prepared in portable test strips through a simple process and used to achieve the naked-eye detection of malononitrile in environmental systems as designed.
Role of TAM Receptors in Antimalarial Humoral Immune Response
Authors: John Lijo , Vijay Rahul
Published: April 2024

Immune response against malaria and the clearance of Plasmodium parasite relies on germinal-center-derived B cell responses that are temporally and histologically layered. Despite a well-orchestrated germinal center response, anti-Plasmodium immune response seldom offers sterilizing immunity. Recent studies report that certain pathophysiological features of malaria such as extensive hemolysis, hypoxia as well as the extrafollicular accumulation of short-lived plasmablasts may contribute to this suboptimal immune response. In this review, we summarize some of those studies and attempt to connect certain host intrinsic features in response to the malarial disease and the resultant gaps in the immune response.
Antimicrobial Resistance Genes in Respiratory Bacteria from Weaned Dairy Heifers
Authors: Depenbrock Sarah , Schlesener Cory , Aly Sharif , Williams Deniece , ElAshmawy Wagdy , McArthur Gary , Clothier Kristin , Wenz John , Fritz Heather , Chigerwe Munashe , Weimer Bart
Published: April 2024

Bovine respiratory disease (BRD) is the leading cause of mortality and antimicrobial drug (AMD) use in weaned dairy heifers. Limited information is available regarding antimicrobial resistance (AMR) in respiratory bacteria in this population. This study determined AMR gene presence in 326 respiratory isolates (Pasteurella multocida, Mannheimia haemolytica, and Histophilus somni) from weaned dairy heifers using whole genome sequencing. Concordance between AMR genotype and phenotype was determined. Twenty-six AMR genes for 8 broad classes of AMD were identified. The most prevalent, medically important AMD classes used in calf rearing, to which these genes predict AMR among study isolates were tetracycline (95%), aminoglycoside (94%), sulfonamide (94%), beta-lactam (77%), phenicol (50%), and macrolide (44%). The co-occurrence of AMR genes within an isolate was common; the largest cluster of gene co-occurrence encodes AMR to phenicol, macrolide, elfamycin, β-lactam (cephalosporin, penam cephamycin), aminoglycoside, tetracycline, and sulfonamide class AMD. Concordance between genotype and phenotype varied (Matthew’s Correlation Coefficient ranged from −0.57 to 1) by bacterial species, gene, and AMD tested, and was particularly poor for fluoroquinolones (no AMR genes detected) and ceftiofur (no phenotypic AMR classified while AMR genes present). These findings suggest a high genetic potential for AMR in weaned dairy heifers; preventing BRD and decreasing AMD reliance may be important in this population.
Evaluation of Renal Function with Urinary NGAL and Doppler Ultrasonography in ICU Patients: A 1-Year Observational Pilot Study
Authors: Brogi Etrusca , Rago Rocco , Forfori Francesco
Published: April 2024

Background: We estimated the diagnostic accuracy of urinary NGAL for the diagnosis of AKI. Methods: Urinary NGAL and Creatinine were measured daily for up to 3 days. Doppler ultrasonography was performed within 24 h of admission and for the following 3 days. Results: Of the 21 patients, 44% had AKI during their ICU stay. The AKI group presented with higher values of serum Creatinine, renal length, MDRD as well as SAPS II already at admission. Urinary NGAL was significantly higher among patients with AKI and patients AKI-no at T0 (p < 0.0001) and increased steadily on T1 and T2. Urinary NGAL seemed to be a notable diagnostic marker for AKI from the first measurement (T0) with an area under the ROC of 0.93 (95% CI = 0.78–0.99) with a sensitivity of 99%. RRI levels were slightly higher in the AKI group at each time and increased gradually from T0 to T2 but reached statistical significance only at T2 (p = 0.02). Renal length and SAPS II at T0 showed high AuRoc and sensitivity. Conclusions: Urinary NGAL is a valuable marker for AKI in intensive care settings. It seemed that a pre-existing chronic renal disease, the SAPS II and the NGAL at admission represented the principal predictors of AKI.
Can Glatiramer Acetate Prevent Cognitive Impairment by Modulating Oxidative Stress in Patients with Multiple Sclerosis?
Authors: Gil-Sánchez Anna , Gonzalo Hugo , Canudes Marc , Nogueras Lara , González-Mingot Cristina , Valcheva Petya , Torres Pascual , Serrano Jose Carlos , Peralta Silvia , Solana Maria José , Brieva Luis
Published: April 2024

Multiple sclerosis (MS) is an autoimmune disease characterized by demyelination and neuroinflammation, often accompanied by cognitive impairment. This study aims (1) to investigate the potential of glatiramer acetate (GA) as a therapy for preventing cognitive decline in patients with MS (pwMS) by modulating oxidative stress (OS) and (2) to seek out the differences in cognition between pwMS in a cohort exhibiting good clinical evolution and control subjects (CS). An exploratory, prospective, multicentre, cross-sectional case–control study was conducted, involving three groups at a 1:1:1 ratio—41 GA-treated pwMS, 42 untreated pwMS, and 42 CS. The participants performed a neuropsychological battery and underwent venepuncture for blood sampling. The inclusion criteria required an Expanded Disability Status Scale score of ≤3.0 and a minimum of 5 years of MS disease. Concerning cognition, the CS had a better performance than the pwMS (p = <0.0001), and between those treated and untreated with GA, no statistically significant differences were found. Regarding oxidation, no statistically significant differences were detected. Upon categorizing the pwMS into cognitively impaired and cognitively preserved groups, the lactate was elevated in the pwMS with cognitive preservation (p = 0.038). The pwMS exhibited a worse cognitive performance than the CS. The pwMS treated with GA did not show an improvement in oxidation. Lactate emerged as a potential biomarker for cognitive preservation.
MicroRNA Profiling Revealed the Mechanism of Enhanced Cold Resistance by Grafting in Melon (Cucumis melo L.)
Authors: Lang Xinmei , Zhao Xuan , Zhao Jiateng , Ren Tiantian , Nie Lanchun , Zhao Wensheng
Published: April 2024

Grafting is widely used to improve the resistance to abiotic stresses in cucurbit plants, but the effect and molecular mechanism of grafting on cold stress are still unknown in melon. In this study, phenotypic characteristics, physiological indexes, small-RNA sequencing and expression analyses were performed on grafted plants with pumpkin rootstock (PG) and self-grafted plants (SG) to explore the mechanism of changed cold tolerance by grafting in melon. Compared with SG plants, the cold tolerance was obviously enhanced, the malondialdehyde (MDA) content was significantly decreased and the activities of antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT; peroxidase, POD) were significantly increased in PG plants. Depend on differentially expressed miRNA (DEM) identification and expression pattern analyses, cme-miR156b, cme-miR156f and chr07_30026 were thought to play a key role in enhancing low-temperature resistance resulting from grafting. Subsequently, 24, 37 and 17 target genes of cme-miR156b, cme-miR156f and chr07_30026 were respectively predicted, and 21 target genes were co-regulated by cme-miR156b and cme-miR156f. Among these 57 unique target genes, the putative promoter of 13 target genes contained the low-temperature responsive (LTR) cis-acting element. The results of qRT-PCR indicated that six target genes (MELO3C002370, MELO3C009217, MELO3C018972, MELO3C016713, MELO3C012858 and MELO3C000732) displayed the opposite expression pattern to their corresponding miRNAs. Furthermore, MELO3C002370, MELO3C016713 and MELO3C012858 were significantly downregulated in cold-resistant cultivars and upregulated in cold-sensitive varieties after cold stimulus, and they acted as the key negative regulators of low-temperature response in melon. This study revealed three key miRNAs and three putative target genes involved in the cold tolerance of melon and provided a molecular basis underlying how grafting improved the low-temperature resistance of melon plants.
Climate-Affected Australian Tropical Montane Cloud Forest Plants: Metabolomic Profiles, Isolated Phytochemicals, and Bioactivities
Authors: Gempo Ngawang , Yeshi Karma , Crayn Darren , Wangchuk Phurpa
Published: April 2024

The Australian Wet Tropics World Heritage Area (WTWHA) in northeast Queensland is home to approximately 18 percent of the nation’s total vascular plant species. Over the past century, human activity and industrial development have caused global climate changes, posing a severe and irreversible danger to the entire land-based ecosystem, and the WTWHA is no exception. The current average annual temperature of WTWHA in northeast Queensland is 24 °C. However, in the coming years (by 2030), the average annual temperature increase is estimated to be between 0.5 and 1.4 °C compared to the climate observed between 1986 and 2005. Looking further ahead to 2070, the anticipated temperature rise is projected to be between 1.0 and 3.2 °C, with the exact range depending on future emissions. We identified 84 plant species, endemic to tropical montane cloud forests (TMCF) within the WTWHA, which are already experiencing climate change threats. Some of these plants are used in herbal medicines. This study comprehensively reviewed the metabolomics studies conducted on these 84 plant species until now toward understanding their physiological and metabolomics responses to global climate change. This review also discusses the following: (i) recent developments in plant metabolomics studies that can be applied to study and better understand the interactions of wet tropics plants with climatic stress, (ii) medicinal plants and isolated phytochemicals with structural diversity, and (iii) reported biological activities of crude extracts and isolated compounds.
Linear Capacitive Pressure Sensor with Gradient Architecture through Laser Ablation on MWCNT/Ecoflex Film
Authors: Jiang Chenkai , Sheng Bin
Published: April 2024

The practical application of flexible pressure sensors, including electronic skins, wearable devices, human–machine interaction, etc., has attracted widespread attention. However, the linear response range of pressure sensors remains an issue. Ecoflex, as a silicone rubber, is a common material for flexible pressure sensors. Herein, we have innovatively designed and fabricated a pressure sensor with a gradient micro-cone architecture generated by CO2 laser ablation of MWCNT/Ecoflex dielectric layer film. In cooperation with the gradient micro-cone architecture and a dielectric layer of MWCNT/Ecoflex with a variable high dielectric constant under pressure, the pressure sensor exhibits linearity (R2 = 0.990) within the pressure range of 0–60 kPa, boasting a sensitivity of 0.75 kPa−1. Secondly, the sensor exhibits a rapid response time of 95 ms, a recovery time of 129 ms, hysteresis of 6.6%, and stability over 500 cycles. Moreover, the sensor effectively exhibited comprehensive detection of physiological signals, airflow detection, and Morse code communication, thereby demonstrating the potential for various applications.
Electrical Characterization of Epoxy Nanocomposite under High DC Voltage
Authors: Alsoud Ammar , Daradkeh Samer I. , Al-Bashaish Saleh R. , Shaheen Adel A. , Jaber Ahmad M. D. (Assa’d) , Abuamr Adel M. , Mousa Marwan S. , Holcman Vladimír
Published: April 2024

This work studies the direct current breakdown characteristics of unfilled epoxy and epoxy nonconductive nanocomposites (SiO2,MgO and Al2O3). It also examines the variation of electrical properties in epoxy nanocomposites. The novel aspect of this study is that the samples of Epoxy nanocomposite were exposed to high voltages of up to six kilo volts for three hours using field electron microscopy under high vacuum conditions (10−5 mbar). The current emitted from these samples was measured at three different intervals of time. In addition, the influence of high voltage on the permittivity, loss factor (tan(δ)), and conductivity of the epoxy nanocomposite was studied. This evaluation was conducted before and after applying the voltage at room temperature, The frequency range extends from 10−2–10−7 Hz using the Novo Control Alpha-A analyzer. Current–voltage characterization was performed through field electron microscopy. The samples were characterized by scanning electron microscopy–energy dispersive X-ray spectroscopy and Fourier Transform Infrared Spectroscopy. The unfilled epoxy exhibited structural degradation, resulting in the formation of holes when exposed to high voltages of up to six kilo volts, leading to a reduction in electrical properties. Nevertheless, the addition of nanoparticles shows a significant increase in the operational lifetime of the epoxy nanocomposite. The degree of increase in the lifetime of epoxy composite varied depending on several factors such as the type of NPs introduced and their respective sizes. The epoxy/Al2O3 nanocomposite comparing with epoxy/MgO and epoxy/SiO2 nanocomposite showed elevated resistance to direct current breakdown strength and maintaining its dielectric.
Photopolymerization of Limonene Dioxide and Vegetable Oils as Biobased 3D-Printing Stereolithographic Formulation
Authors: Clerget Mégane , Gagnon Eric , Claverie Jerome P.
Published: April 2024

Epoxidized vegetable oils and limonene dioxide, a bis-epoxide derived from the terpene limonene, are photo-copolymerized to yield highly crosslinked networks with high conversion of all epoxide groups at ambient temperature. However, the slow polymerization of such biobased formulation polymerizes is not compatible for a use in a commercial SLA 3D printer. Adding an acrylated epoxidized vegetable oil to the bis-epoxide leads to a decrease of curing time and an increase in LDO conversion to polymer. For example, in a 60:40 wt:wt mixture of LDO and epoxidized soybean oil, the conversions of both exocyclic and endocyclic epoxide groups of LDO are ≥95%. These formulations were successfully used in SLA 3D printers, leading to generation of hard and dry complex objects using biobased formulations.
Molded Plywood with Proportions of Beech Bark in Adhesive Mixtures: Production on an Industrial Scale
Authors: Reh Roman , Kristak Lubos , Sedliacik Jan , Bekhta Pavlo , Wronka Anita , Kowaluk Grzegorz
Published: April 2024

Molded plywood is used for furniture components such as seats, backrests, or integral seat shells, and it must be durable and harmless to health. Molded plywood is made with urea-formaldehyde (UF) adhesives; therefore, the issue of the fillers used in them is important. The potential of using ground beech (Fagus sylvatica L.) bark as an eco-friendly additive in UF adhesives for molded plywood manufacturing was investigated in this work. Wheat flour was used as a reference filler. The beech bark (BB) level as a filler was 10%, a value verified under laboratory conditions. Nine-layer flat and molded plywood were produced under industrial conditions from beech veneers bonded with a UF adhesive mixture. The mechanical (bending strength and bonding quality) and physical (swelling and absorbency values after 2 and 24 h) properties of the industrially fabricated molded plywood were evaluated and compared with the European standard requirements (EN 310 and EN 314-2). The mechanical properties of the molded plywood with the addition of BB in the adhesive mixture were acceptable and met these standards’ requirements. The positive effect of BB in the UF adhesive mixture on a reduction in formaldehyde emissions from the molded plywood was also confirmed. BB, considered to be wood-processing industry waste or a by-product, has significant potential to be used as a filler in UF resins for molded plywood production, providing an environmentally friendly, inexpensive solution for the industrial valorization of bark as a bio-based formaldehyde scavenger.
Porous Coordination Polymer MOF-808 as an Effective Catalyst to Enhance Sustainable Chemical Processes
Authors: Ferreira Catarina E. S. , Santos-Vieira Isabel , Gomes Carlos R. , Balula Salete S. , Cunha-Silva Luís
Published: April 2024

The improvement of sustainable chemical processes plays a pivotal role in safe environmental and societal development, for example, by reducing the use of hazardous substances, preventing chemical waste, and improving the efficiency of chemical reactions to obtain added-value compounds. In this context, the porous coordination polymer MOF-808 (MOF, metal–organic framework) was prepared by a straightforward method in water, at room temperature, and was unequivocally characterized by powder X-ray diffraction, vibrational spectroscopy, thermogravimetric analysis, and scanning electron microscopy. MOF-808 material was applied for the first time as catalysts in ring-opening aminolysis reactions of epoxides. It demonstrated high activity and selectivity for reactions of styrene oxide and cyclohexene oxide with aniline, using a very low amount of an eco-sustainable solvent (0.5 mL of EtOH), at 70 °C. Moreover, MOF-808 demonstrated high stability in the catalytic reaction conditions applied, and a notable reuse capacity of up to 20 consecutive reaction cycles, without significant variation in its catalytic performance. In fact, this Zr-based porous coordination polymer prepared by environment-friendly conditions proved to be a novel efficient heterogeneous catalyst, promoting the ring-opening reaction of epoxides under more sustainable conditions, and using a very low amount of catalyst.
Preparation of Mesophase Pitch with Fine-Flow Texture from Ethylene Tar/Naphthalene by Catalytic Synthesis for High-Thermal-Conductivity Carbon Fibers
Authors: He Xubin , Wu Xiao , Shi Kui , Zhu Shipeng , Huang Dong , Liu Hongbo , Liu Jinshui
Published: April 2024

Mesophase pitch is usually prepared by radical polymerization or catalytic polymerization from coal tar, petroleum, and aromatic compounds, and the catalytic synthesis of mesophase pitch from pure aromatic compounds is more controllable in the preparation of high-quality mesophase pitch. However, the corrosive and highly toxic nature of the catalyst has limited the further development of this method. In this study, mesophase pitch was synthetized using ethylene tar and naphthalene as raw materials and boron trifluoride diethyl etherate as a catalyst. The effect of the catalytic reaction on the structure and properties of the mesophase pitch was investigated. The results show that naphthalene plays an important role in the mesophase content and reaction pressure (from above 6 MPa to 2.35 MPa). Mesophase pitch with fine-flow texture can be prepared by introducing more methylene groups, naphthenic structures, and aliphatic hydrocarbons during synthesis. Carbon fibers prepared from mesophase pitch show a split structure, and the thermal conductivity is 730 W/(m·K). This work provides theoretical support for lower toxicity and causticity and for reaction-controlled technology for the synthesis of high-purity mesophase pitch.
Recent Progress of Anti-Freezing, Anti-Drying, and Anti-Swelling Conductive Hydrogels and Their Applications
Authors: Li Ying , Cheng Qiwei , Deng Zexing , Zhang Tao , Luo Man , Huang Xiaoxiao , Wang Yuheng , Wang Wen , Zhao Xin
Published: April 2024

Hydrogels are soft–wet materials with a hydrophilic three-dimensional network structure offering controllable stretchability, conductivity, and biocompatibility. However, traditional conductive hydrogels only operate in mild environments and exhibit poor environmental tolerance due to their high water content and hydrophilic network, which result in undesirable swelling, susceptibility to freezing at sub-zero temperatures, and structural dehydration through evaporation. The application range of conductive hydrogels is significantly restricted by these limitations. Therefore, developing environmentally tolerant conductive hydrogels (ETCHs) is crucial to increasing the application scope of these materials. In this review, we summarize recent strategies for designing multifunctional conductive hydrogels that possess anti-freezing, anti-drying, and anti-swelling properties. Furthermore, we briefly introduce some of the applications of ETCHs, including wearable sensors, bioelectrodes, soft robots, and wound dressings. The current development status of different types of ETCHs and their limitations are analyzed to further discuss future research directions and development prospects.
Study on the Melt Rheological Characterization of Micro-Tube Gas-Assisted Extrusion Based on the Cross-Scale Viscoelastic Model
Authors: Zhang Xiaohui , Huang Xingyuan , Liu Bin , Chen Shuiquan
Published: April 2024

In the micro-tube gas-assisted extrusion process, flow theories ignoring cross-scale viscoelastic variations fail to effectively characterize the rheological state of the melt. To investigate the impact of cross-scale viscoelastic variation on the quality of the micro-tube gas-assisted extrusion, a 3D multiphase flow extrusion model incorporating a double gas-assisted layer was developed. Subsequently, we modified the DCPP constitutive equations based on the cross-scale factor model. Both the traditional and gas-assisted extrusions were simulated under macroscale and cross-scale models using the Ansys Polyflow. Finally, using the established gas-assisted extrusion platform, extrusion experiments were conducted. The results indicate that, owing to the reduced melt viscosity under the cross-scale model, the deformation behavior of the melt is more pronounced than in the macroscale model. The cross-scale model’s numerical results more closely match the experimental outcomes under the same parameters, thereby confirming the feasibility of the theoretical analysis and numerical simulation. Moreover, the predictive capability of the cross-scale model for the micro-tube gas-assisted extrusion is further validated through numerical and experimental analyses with varying parameters. It is demonstrated that the cross-scale viscoelastic variation is a critical factor that cannot be overlooked in the gas-assisted extrusion.
Improvement in Crystallization, Thermal, and Mechanical Properties of Flexible Poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) Bioplastic with Zinc Phenylphosphate
Authors: Pakkethati Kansiri , Srihanam Prasong , Manphae Apirada , Rungseesantivanon Wuttipong , Prakymoramas Natcha , Lan Pham Ngoc , Baimark Yodthong
Published: April 2024

Poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) (PLLA-PEG-PLLA) shows promise for use in bioplastic applications due to its greater flexibility over PLLA. However, further research is needed to improve PLLA-PEG-PLLA’s properties with appropriate fillers. This study employed zinc phenylphosphate (PPZn) as a multi-functional filler for PLLA-PEG-PLLA. The effects of PPZn addition on PLLA-PEG-PLLA characteristics, such as crystallization and thermal and mechanical properties, were investigated. There was good phase compatibility between the PPZn and PLLA-PEG-PLLA. The addition of PPZn improved PLLA-PEG-PLLA’s crystallization properties, as evidenced by the disappearance of the cold crystallization temperature, an increase in the crystallinity, an increase in the crystallization temperature, and a decrease in the crystallization half-time. The PLLA-PEG-PLLA’s thermal stability and heat resistance were enhanced by the addition of PPZn. The PPZn addition also enhanced the mechanical properties of the PLLA-PEG-PLLA, as demonstrated by the rise in ultimate tensile stress and Young’s modulus. We can conclude that the PPZn has potential for use as a multi-functional filler for the PLLA-PEG-PLLA composite due to its nucleating-enhancing, thermal-stabilizing, and reinforcing ability.
Characterization and Simulation of the Interface between a Continuous and Discontinuous Carbon Fiber Reinforced Thermoplastic by Using the Climbing Drum Peel Test Considering Humidity
Authors: Christ  Nicolas , Scheuring  Benedikt M. , Schelleis  Christoph , Liebig  Wilfried V. , Montesano John , Weidenmann  Kay A. , Hohe  Jörg
Published: April 2024

The objective of this paper is to investigate the debonding behavior of the interface between continuously and discontinuously fiber reinforced thermoplastics using the climbing drum peel test. The study emphasizes on the importance of considering different climatic boundary conditions on the properties of thermoplastics. Specimens with varying moisture contents, from 0m.% up to above 6m.% are prepared and tested. It is observed that an increase in moisture content from 0m.% to 2m.% results in an increase of the fracture surface energy from 1.07·103J/m2 to 2.40·103J/m2 required to separate the two materials, but a further increase in moisture to 6.35m.% conversely results in a subsequent decrease of the required energy to 1.91·103J/m2. The study presents an explanatory model of increasing plasticization of the polymer due to increased polymer chain mobility, which results in more deformation energy being required to propagate the crack, which is corroborated in SEM investigations of the fracture surface. A further increase in humidity leads to polymer degradation due to hydrolysis, which explains the subsequent reduction of the fracture energy. The experimental set up is modeled numerically for the first time with cohesive surfaces, which could successfully reproduce the effective force-displacement curve in the experiment by varying the interface parameters in the model over an influence length, allowing the conclusion of a process induced variation in the interface properties over a specific consolidation length.
Improving the 3D Printability and Mechanical Performance of Biorenewable Soybean Oil-Based Photocurable Resins
Authors: Bodor Marius , Lasagabáster-Latorre Aurora , Arias-Ferreiro Goretti , Dopico-García María Sonia , Abad María-José
Published: April 2024

The general requirement of replacing petroleum-derived plastics with renewable resources is particularly challenging for new technologies such as the additive manufacturing of photocurable resins. In this work, the influence of mono- and bifunctional reactive diluents on the printability and performance of resins based on acrylated epoxidized soybean oil (AESO) was explored. Polyethylene glycol di(meth)acrylates of different molecular weights were selected as diluents based on the viscosity and mechanical properties of their binary mixtures with AESO. Ternary mixtures containing 60% AESO, polyethylene glycol diacrylate (PEGDA) and polyethyleneglycol dimethacrylate (PEG200DMA) further improved the mechanical properties, water resistance and printability of the resin. Specifically, the terpolymer AESO/PEG575/PEG200DMA 60/20/20 (wt.%) improved the modulus (16% increase), tensile strength (63% increase) and %deformation at the break (21% increase), with respect to pure AESO. The enhancement of the printability provided by the reactive diluents was proven by Jacobs working curves and the improved accuracy of printed patterns. The proposed formulation, with a biorenewable carbon content of 67%, can be used as the matrix of innovative resins with unrestricted applicability in the electronics and biomedical fields. However, much effort must be done to increase the array of bio-based raw materials.
Mechanistic Insights into the Effects of Ureas and Monomers on the Ring-Opening Alternating Copolymerization of Epoxides and Anhydrides Catalyzed by Organic Base/Urea
Authors: Jiang Lihang , Wu Yong , Tian Xin , Xue Wanpeng , Li Hanghang , Kang Xiaohui , Li Bin
Published: April 2024

Aliphatic polyester is an important polyester material with good biocompatibility and degradability, which can be synthesized through ring-opening alternating copolymerization (ROAC) of epoxides and anhydrides. Herein, density functional theory (DFT) is used to explore the mechanism of ROAC of epoxides (propylene oxide (PO), styrene oxide (SO), epichlorohydrin (ECH), and cyclohexane oxide (CHO)) and phthalic anhydride (PA) catalyzed by bis(triphenylphosphine) ammonium chloride (PPNCl) and ureas. It was found that the ring-opening polymerization (ROP) of epoxides is the rate-controlling step, and the benzyl alcohol (BnOH) as the initiator has little effect on the polymerization activity, which was consistent with previous experimental results. Calculated comparisons of the ROAC activity of CHO/PA catalyzed by four different ureas indicate that as the Lewis acidity of the urea increased, the energy barriers of the copolymerization increased and the activity decreased. The main reason was that the strong hydrogen-bonding interactions stabilized the key intermediate of the rate-controlling step and inhibited subsequent monomer insertion. Based on this, a series of new ureas with higher catalytic activity were designed by introducing electron-donating substituents. In SO polymerization, increasing the Lewis acidity of urea can improve the SO regioselectivity. In addition, the monomer ECH with CH2Cl shows higher activity of ROAC than PO and SO, which could be ascribed to the fact that the strong electron-withdrawing Cl atom stabilizes the transition state in the rate-controlling step and reduces the reaction energy barrier.
Solution-Phase Synthesis of KCl Nanocrystals Templated by PEO-PPO-PEO Triblock Copolymers Micelles
Authors: Sun Lingling , Li Min , Li Fei , Wang Fuchun , Liang Xiangfeng , Shou Qinghui
Published: April 2024

The current work introduces the synthesis of inorganic salt nano/micro-crystals during the reduction of hydrogen tetrachloroaurate(III) by Pluronic triblock copolymers (P123, PEO20–PPO70–PEO20). The morphologies and component were confirmed using an electron microscope with an electronic differential system (EDS), and the crystal structures were determined with X-ray diffraction (XRD). The morphologies highly depend on the concentrations of Pluronic and pH values. The mean size of the nanocrystal and hollow micro-crystal were controlled typically in the range of 32–150 nm (side length) and 1.4 μm, respectively. Different from the electrospray–ionization (EI) method, a model in which KCl forms a supersaturated solution in the micellar core of Pluronic is used to explain the formation process. This work provides the new insight that inorganic salt nanocrystals could be synthesized with the template of micelles in pure aqueous solutions.
Efficiency of Utilization of Metabolizable Energy for Carcass Energy Retention in Broiler Chickens Fed Maize, Wheat or a Mixture
Authors: Pirgozliev Vasil Radoslavov , Hammandy Muhammad Hassan , Mansbridge Stephen Charles , Whiting Isobel Margaret , Rose Stephen Paul
Published: April 2024

The study aimed to quantify carcass fat and protein retention, and the efficiency of carcass energy utilization (Kre) resulting from feeding broiler chickens diets containing wheat, maize or mixtures of both as the major cereal ingredient. The apparent metabolizable energy (AME) of the four cereal samples was determined in adult cockerels. There was a linear (p < 0.001) increase in AME with increasing amounts of maize within the four cereal mixtures, with analyses indicating that the AME of maize was 1.4 MJ/kg greater than that of wheat. A second bioassay with growing chickens was used to determine Kre in each cereal, measured as carcass fat and protein from 7 to 21d age. Increasing proportions of maize resulted in linear increases in carcass fat and energy retained from fat (p < 0.001). However, the carcass protein and energy retained from protein did not follow the same pattern as fat (p = 0.121), but rather decreased numerically (L = 0.032). The Kre tended (p = 0.060) to increase with greater proportion of maize in a linear fashion (L = 0.009). Although AME values of cereals were confirmed to be additive, this could not be confirmed for Kre. This data can be used for optimizing energy utilization models for growing broilers.
Preparation and Mechanical Properties of PBAT/Silanized Cellulose Composites
Authors: Wang Xiangyun , Mo Wenlong , Zeng Yongming , Wang Jide
Published: April 2024

Polybutylene adipate-terephthalate (PBAT) is a fully biodegradable polyester, which has been proven to be the most suitable alternative to traditional plastics. However, due to the low strength of PBAT (17.2 MPa) and high price, the use of PBAT has a degree of limitations. To obtain a cost-effective and high-performance composite material of PBAT, for this study we selected microcrystalline cellulose, which is inexpensive and easily available, as the reinforcing medium. However, due to the hydrophobicity of PBAT, the mechanical properties of PBAT when mixed with hydrophilic cellulose were low. In order to improve the compatibility of cellulose and PBAT, this study selected hexadecyltrimethoxysilane (HDTMS) containing long carbon chains to silanize microcrystalline cellulose (MCC) to obtain silanized cellulose (SG). Three types of SGs with different degrees of silanization were obtained by controlling HDTMS with different mass ratios (1:10; 3:10; 5:10) to react with MCC. Characterization of these three types of SGs was conducted using FTIR, TEM, and water absorption analysis. The results demonstrated the successful synthesis of SG. With the increase in the reaction ratio of HDTMS and MCC, the size of the nanoparticles increases, and the water absorption decreases significantly. Subsequently, PBAT/SG composites were prepared by blending three kinds of silanized cellulose with PBAT in different proportions by the sol-gel method. To study the thermal stability and compatibility, the mechanical properties of the composites were evaluated, including thermogravimetric testing, scanning analysis, and dynamic thermomechanical testing. The optimal blending ratio and the optimal type of silane cellulose were found. Analysis of the mechanical properties revealed that the tensile strength initially increased and then decreased with increasing blending ratio for all three composites tested. Among them, the PBAT/SG2 composites exhibit superior performance, with a maximum tensile strength reaching 22 MPa at an 85/15 blending ratio, nearly 30% higher than that of pure PBAT alone. The addition of SG significantly improved the strength of the PBAT, and SG2 is more suitable for preparing high-strength composite materials. In addition, after the addition of SG, the yield stress of the composite is improved while maintaining good thermal stability. Both the SEM and DMA results indicated good compatibility of the PBAT/SG composites. This study provides a new idea for the industrial-scale development of degradable polyesters with low cost and good mechanical properties.
Electrolytic Regeneration of Spent Caustic Soda from CO2 Capture Systems
Authors: Mohammadpour Hossein , Pivrikas Almantas , Cheng Ka Yu , Ho Goen
Published: April 2024

The traditional electrochemical caustic soda recovery system uses the generated pH gradient across the ion exchange membrane for the regeneration of spent alkaline absorbent from CO2 capture. This electrochemical CO2 capture system releases the by-products H2 and O2 at the cathode and anode, respectively. Although effective for capturing CO2, the slow kinetics of the oxygen evolution reaction (OER) limit the energy efficiency of this technique. Hence, this study proposed and validated a hybrid electrochemical cell based on the H2-cycling from the cathode to the anode to eliminate the reliance on anodic oxygen generation. The results show that our lab-scale prototype enabled effective spent caustic soda recovery with an electron utilisation efficiency of 90%, and a relative carbonate/bicarbonate diffusional flux of approximately 40%. The system also enabled the regeneration of spent alkaline absorbent with a minimum electrochemical energy input of 0.19 kWh/kg CO2 at a CO2 recovery rate of 0.7 mol/m2/h, accounting for 30% lower energy demand than a control system without H2-recycling, making this technique a promising alternative to the conventional thermal regeneration technology.
Studies on Reactive Extraction of Itaconic Acid from Fermentation Broths
Authors: Blaga Alexandra Cristina , Kloetzer Lenuta , Cascaval Dan , Galaction Anca-Irina , Tucaliuc Alexandra
Published: April 2024

Itaconic acid is a high-value organic acid that serves as a platform molecule in different industries. This research focuses on the separation of itaconic acid using reactive extraction as a sustainable and efficient method for acid recovery from fermentation broth. Itaconic acid was produced through fungal fermentation processes involving Aspergillus terreus ATCC® 32588™, obtaining a concentration of 47 g/L in the final broths. For the reactive extraction system, the organic phase included tri-n-octylamine as an extractant dissolved in dichloromethane or n-heptane and 1-octanol as a phase modifier. The effect of the main influencing factors (pH of the aqueous phase, extractant concentrations in the organic phase, and the addition of 1-octanol) on extraction efficiency was investigated. The highest extraction degree (97%) was achieved using an organic phase with tri-n-octylamine dissolved in dichloromethane and with 20% 1-octanol. Conversely, in the reactive extraction system with tri-n-octylamine dissolved in n-heptane and 20% 1-octanol, the extraction efficiency reached 67%. This finding suggests a promising separation system that is less toxic for microorganisms. The study results highlight the feasibility of employing reactive extraction systems for the direct separation of itaconic acid.
Research on Multi-Physical Field Characteristics of Deep Coal Seam Mining Based on the Rock-Coal-Rock Model
Authors: Du Feng , Zhang Yi , Dai Linchao , Cui Weilong , Wang Bo , Sun Jiazhi
Published: April 2024

In order to disclose the multi-physical field characteristics of the deep coal seam mining process and their dynamic evolution legislation, based on the “rock-coal-rock” model, during the mining process, the stress field, displacement field, energy field, and plastic zone evolution process are all simulated using FLAC3D6.0. The findings show that stress in the original rock is redistributed as a result of coal seam mining, creating a pressure relief zone in the middle of the goaf and advanced support pressure in the front part of the working face. The roof falls following the termination of coal seam mining. The collapsed blocks fill the middle of the goaf, playing a supporting role. The floor bulges as a new supporting pressure zone forms and builds up high elasticity. The stress reduction zone shifts from a rectangular to an inner circular distribution and an outer square as the working face’s mining distance increases and the range of the fracture field expands accordingly. In addition, a complete model was constructed to verify the correctness of the “rock-coal-rock” model. The stress, displacement, and energy curves of the overlying strata at a distance of 12 m from the bottom of the coal seam in the middle of the goaf obtained by the two methods were basically consistent. Ultimately, the findings of the numerical simulation were compared with the advanced support pressure data that were acquired on-site and they were good. This work can provide a reference for the safe mining of deep coal seams.
Examining Position Effects on Students’ Ability and Test-Taking Speed in the TIMSS 2019 Problem-Solving and Inquiry Tasks: A Structural Equation Modeling Approach
Authors: Liu Joyce Xinle , Bulut Okan , Johnson Matthew D.
Published: April 2024

Position effects occur when changes in item positions on a test impact the test outcomes (e.g., item parameters or test scores). Previous studies found that position effects may vary by the testing context and conditions and thus affect each test-taker differently. With the increasing adoption of digital assessments involving innovative item types that are focused on problem-solving skills, it is also essential to study position effects within this context. This study incorporates item-level scores and screen-level response time data from the Trends in International Mathematics and Science Study (TIMSS) 2019 problem-solving and inquiry tasks for Grade 4 students to examine position effects on students’ ability and test-taking speed. This dataset included responses from 27,682 students from 36 countries. A structural equation modeling approach was employed to model ability and test-taking speed within the same model. The results indicated a small but statistically significant booklet effect on students’ overall mathematics and science ability. The impact of block position changes within the booklets seemed to be greater than the impact of a reordering of subjects tested in the two sessions. The results also showed that when an item block was placed earlier in a test session, students spent more time on the items and performed better. The implications of these findings are discussed.
Ancient Travellers, Intercultural Contact, and the Fear of Gods
Authors: Uusimäki Elisa
Published: April 2024

Although the fear of Yhwh has been presented as an intrinsic feature of the ancient Israelite religion, the fear of God(s) is not limited to the people of Israel in the Hebrew Bible, and similar ideas of fearing deities occur in various texts produced by neighbouring cultures in the ancient eastern Mediterranean. This article investigates the prosocial role of this virtue in situations of human mobility and intercultural contact in the light of the Hebrew Bible and the Odyssey. First, I analyse those Hebrew Bible texts in which the fear of God(s) characterizes or is presented as being intelligible to non-Israelite people in situations involving movement and cultural encounter (Gen 20:11; 42:18; Exod 1:17, 21; Deut 25:18; Jon 1:9). Second, I explore the fear motif in other texts from the ancient eastern Mediterranean region and argue that biblical scholars have overlooked illuminating intertexts found in ancient Greek literature. I especially highlight the interpretative importance of the Odyssey, which frequently stresses the prosocial role of the virtue of fearing deities in the context of travel and contact with outsiders. In so doing, the Odyssey helps us see how the Hebrew Bible texts portraying the fear of God(s) as a universalistic virtue are rooted in and belong to a broader ancient Mediterranean milieu.
Ecumeny at a Crossroads: Toward Unity or Community?
Authors: Porada Rajmund
Published: April 2024

This article addresses determinants of the ecumenical impetus’ weakening in the second half of the twentieth century. This situation invokes a key question about the purpose of the ecumenical journey. Despite the complexity and multiplicity of problems dividing the Churches, it was acknowledged that the main reason for stagnation was differences in understanding the Church. The Dominus Iesus declaration represented a kind of caesura, one marking a divergence in the aims of the ecumenical path, especially in Catholic–Protestant relations. Since then, certain statements on the Protestant side signal a clear attempt at distancing themselves from the concept of visible unity. They have come to prefer an alternative model of a community of Churches. Some have, in turn, put forward arguments for the apparent nature of such an alternative. In fact, the realisation of the Church’s visible unity can only take place “through” and “in” the community of various Churches. The Church herself is the assembly (community) of all peoples and nations in one people under God.
Wheat Yield Robust Prediction in the Huang-Huai-Hai Plain by Coupling Multi-Source Data with Ensemble Model under Different Irrigation and Extreme Weather Events
Authors: Zhao Yanxi , He Jiaoyang , Yao Xia , Cheng Tao , Zhu Yan , Cao Weixing , Tian Yongchao
Published: April 2024

The timely and robust prediction of wheat yield is very significant for grain trade and food security. In this study, the yield prediction model was developed by coupling an ensemble model with multi-source data, including vegetation indices (VIs) and meteorological data. The results showed that green chlorophyll vegetation index (GCVI) is the optimal remote sensing (RS) variable for predicting wheat yield compared with other VIs. The accuracy of the adaptive boosting- long short-term memory (AdaBoost-LSTM) ensemble model was higher than the LSTM model. AdaBoost-LSTM coupled with optimal input data had the best performance. The AdaBoost-LSTM model had strong robustness for predicting wheat yield under different irrigation and extreme weather events in general. Additionally, the accuracy of AdaBoost-LSTM for rainfed counties was higher than that for irrigation counties in most years except extreme years. The yield prediction model developed with the characteristic variables of the window from February to April had higher accuracy and smaller data requirements, which was the best prediction window. Therefore, wheat yield can be accurately predicted by the AdaBoost-LSTM model one to two months of lead time before maturity in the HHHP. Overall, the AdaBoost-LSTM model can achieve accurate and robust yield prediction in large-scale regions.
Flextime/Flexspace for All in the Organization? A Study of the Availability, Use, and Consequences of Flexible Work Arrangements for Low and High SES Employees in Nine European Countries
Authors: van der Lippe Tanja , den Dulk Laura , Begall Katia
Published: April 2024

This article investigates the relationship between employee socioeconomic status (SES) and the availability, use, and consequences for employees of flexible work arrangements (working from home and flexible starting and finishing times). Multi-level analyses based on the European Sustainable Workforce Survey (11,011 employees nested in 869 teams at 259 organizations in nine European countries) reveal a negative relationship between low SES employees and the availability of working from home. Lower-status employees also perceive working from home and flexible work times as less available to them and use these arrangements less than higher-status employees. Findings suggest similar outcomes of use for both groups. We found almost no differences between lower and higher SES employees in how using flexible work arrangements affected performance, commitment, and work–life conflict.