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Simple synthesis and high performance are eternal pursuit for polymers. To lower the curing temperature, lower the melt viscosity and improve the processability of high performance phthalonitrile resins, a solvent‐free method was applied to synthesize three from different phenols. Their chemical structure was confirmed by FTIR and NMR spectra, the curing behavior was investigated by DSC and rheology. It was found that the polymerization of phthalonitrile groups could be effectively promoted by benzoxazine moieties and the curing temperature of phthalonitrile groups dropped to around 240°C. Consequently, owing to the high curing reactivity, polymers obtained at relatively low curing temperature possessed high crosslinking density and extremely high thermal stability. P‐apn‐200, which was cured at 200°C, showed 5 wt% weightloss temperature (Td5) of 472°C and char yield (Yc) of 75.77% at 800°C. Moreover, the polymers obtained after curing at 280°C showed superior dimensional stability, CN‐apn‐280 showed extremely low linear expansion coefficient (CTE) of 10.7 ppm/°C. And mP‐apn‐280 showed HR capacity of 3.99 J/g‧K, peak HRR of 4.0 W/K and total HR of 0.8 kJ/g. [ABSTRACT FROM AUTHOR]

Primary patellar dislocation has a certain recurrence rate after either conservative or surgical treatment, and the optimal treatment for patients with primary patellar dislocation of different ages remains unclear. This study aims to compare the clinical efficacy of surgical and conservative treatments for primary patellar dislocation across different age groups. According to the Preferred Reporting Items for Systematic Reviews and Meta‐analyses (PRISMA) checklist, we conducted a systematic search for randomized controlled trials. We searched the PubMed, EMBASE, Cochrane Library, and Web of Science databases for randomized controlled trials of primary patellar dislocation treated surgically or conservatively up to January 2023. Data searching, extraction, analysis, and quality assessment were carried out in accordance with the Cochrane Collaboration guidelines. A total of nine studies with 433 patients were included in our study. There was no statistically significant difference between the two treatment modalities in terms of Kujala score, pain score, patient satisfaction, reoperation, and Tegner score. The rate of re‐dislocation after surgical treatment is lower than that after conservative treatment. Subgroup analysis based on mean age showed that when the age was >20 years, Kujala scores were higher after surgical treatment than after conservative treatment (p < 0.0001, 95% confidence interval [CI] = 10.41–21.30). When the age was ≤20 years, the difference in Kujala scores between the two treatment modalities was not statistically significant. When the age was >20 years, the recurrence rate of patellar dislocation was lower after surgical treatment than after conservative treatment (p = 0.009, 95% CI = 0.08–0.70). When the age was ≤20 years, the difference in the recurrence rate of patellar dislocation between the two treatment modalities was not statistically significant. When the age of patients with primary patellar dislocation is ≤20 years, both surgical and conservative treatments result in similar clinical outcomes. When the age is >20 years, better clinical outcomes can be achieved by opting for surgical treatment. Therefore, surgery may be a better option for patients with primary patellar dislocation whose age is >20 years. [ABSTRACT FROM AUTHOR]

Chirality, a fundamental principle in chemistry, biology, and medicine, is prevalent in nature and in organisms. Chiral molecules, such as DNA, RNA, and proteins, are crucial in biomolecular synthesis, as well as in the development of functional materials. Among these, 1,1′‐binaphthyl‐2,2′‐diol (BINOL) stands out for its stable chiral configuration, versatile functionality, and commercial availability. BINOL is widely employed in asymmetric catalysis and chiral materials. This review mainly focuses on recent research over the past five years concerning the use of BINOL derivatives for constructing chiral macrocycles and cages. Their contributions to chiral luminescence, enantiomeric separation, transmembrane transport, and asymmetric catalysis were examined. [ABSTRACT FROM AUTHOR]

Volatility forecasting, a central issue in financial risk modelling and management, has attracted increasing attention after several major financial market crises. In this article, we draw upon the literature on volatility forecasting and hybrid models to construct the Hybrid‐long short‐term memory (LSTM) models to forecast the intraday realized volatility in three major US stock indexes. We construct the hybrid models by combining one or multiple traditional time series models with the LSTM model, and incorporating either the estimated parameters, or the predicted volatility, or both from the statistical models as additional input values into the LSTM model. We perform the out‐of‐sample test of our Hybrid‐LSTM models in volatility forecasting during the coronavirus disease 2019 (COVID‐19) period. Empirical results show that the Hybrid‐LSTM models can still significantly improve the volatility forecasting performance of the LSTM model during the COVID‐19 period. By analysing how the construction methods may influence the forecasting performance of the Hybrid‐LSTM models, we provide some suggestions on their design. Finally, we identify the optimal Hybrid‐LSTM model for each stock index and compare its performance with the LSTM model on each day during our sample period. We find that the Hybrid‐LSTM models' great capability of capturing market dynamics explains their good performance in forecasting. [ABSTRACT FROM AUTHOR]

Background: Presently, there are no studies that examine the impact of side‐reactions of ethylene oxide hydration on triple‐column reactive‐extractive distillation (TC‐RED). This study addressed this gap by investigating how these side‐reactions influence the energy consumption, total annual cost (TAC), and CO2 emission of the TC‐RED process. Two case studies, which involve the ternary separation of tetrahydrofuran (THF)/ethanol (ETOH)/water and ethyl acetate (EA)/ETOH/water were conducted here. Results: Case studies 1 and 2 showed significant increase in energy consumption (39.68% and 16.56%), TAC (65.57% and 47.88%) and CO2 emission (21.15% and 12.89%) resulting from side‐reactions. The increase in energy consumption, TAC, and CO2 emission is primarily a consequence of the high boiling point of higher glycol product derivatives, altered chemical equilibrium behavior and increased reactant flowrates, which necessitate larger equipment sizes and incur higher capital costs. Notwithstanding this, TC‐RED with side‐reactions still outperforms pressure swing distillation (PSD) for separation of THF/ETOH/water and extractive distillation (ED) for separation of EA/ETOH/water. However, it falls short of double‐column reactive‐extractive distillation (DC‐RED) owing to the need for an additional column. Conclusion: Our study highlights the importance of considering side‐reactions in TC‐RED during process design. Although the decline in performance is a result of the additional complexities brought by side‐reactions, it is important to emphasize that the primary takeaway of this study is that the system model is more realistic. By incorporating side‐reactions into the simulation, we can model the system more comprehensively, providing future researchers with an opportunity to explore and address potential issues resulting from side‐reactions. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

The isotopic composition of lithium (Li) in clinopyroxene (Cpx), determined via in situ micro‐analysis, has been employed as a potential geochemical tool for studying various geological processes such as crust‐mantle recycling, silicate weathering and fluid‐rock interaction. To obtain precise and accurate Li isotopic compositions in Cpx by LA‐MC‐ICP‐MS, synthetic Cpx matrix‐matched reference materials (RMs) were prepared in this study. Six Cpx‐matrix RMs were prepared by mixing metallic oxides with GSP‐2 (granodiorite) or pure L‐SVEC solution and melting them into glasses (GSP‐2 + oxide; L‐SVEC + oxide). Two representative synthetic glasses, CPXA01 and CPXB01, were subjected to a series of analyses to investigate the possible qualification of the RMs for in situ Li isotope measurement by LA‐MC‐ICP‐MS, including elemental homogeneity analysis (elemental mapping analysis and spot analysis), Li isotopic homogeneity analysis and accurate Li isotopic determination. The applicability of the synthetic Cpx‐matrix RMs was highlighted by comparing the δ7Li values of three natural Cpx calibrated against the synthetic Cpx‐matrix RMs and other commonly used RMs with different matrices (NIST SRM 612, BCR‐2G, GOR128‐G, StHs6/80‐G, KL2‐G and T1‐G), respectively. Additionally, CPXB01‐05 RMs with the same matrix but different Li contents were prepared to explore the Li content mismatch effect, which is significant for accurate determination of in situ Li isotopic composition by LA‐MC‐ICP‐MS. The results of the cross‐calibration of Li isotopes in CPXA01 and CPXB01 suggested no obvious Li isotopic fractionation between the two types of glasses (GSP‐2 + oxide; L‐SVEC + oxide). Thus, the two methods of producing Cpx‐matrix RMs are suitable for preparing the matrix‐matched RMs for in situ microanalysis for Li isotopes. [ABSTRACT FROM AUTHOR]

BACKGROUND: The sustainability performance of extractive distillation (ED) that collectively considers energy efficiency, process safety, economic profitability, process control, and environmental emission has not been widely reported. Motivated by this lack of research, we analyzed and compared the sustainability performance of the intensified side‐stream ED (SSED) with that of the conventional extractive distillation (CED) for the separation of binary azeotropic mixtures. Two different design approaches were analyzed; the first approach involves designing the intensified SSED by preserving the original CED column configuration, while the second approach involves optimizing the original column configuration to become a new intensified SSED configuration. RESULTS: We found that preserving the original configuration usually provides energy‐savings, but this advantage is not guaranteed unless the process is optimized. Generally, the reduction in energy consumption improves economic and environmental performance. However, the optimized design has a higher risk index because it is usually larger in size, for the sake of lowering the energy consumption. In addition, the optimized design usually has a higher condition number, which signifies that a more complex control structure is required. CONCLUSION: Altogether, designing the intensified process via process optimization does not always guarantee significant improvement in all sustainability indicators. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

In this paper, the authors apply the feature pyramid network (FPN) to the single‐stage anchor‐free object detection algorithm CenterNet, and the effectiveness of the multi‐level feature fusion of FPN for the object detection algorithm is proved by experiments. However, multi‐level feature fusion leads to an increase in computational cost. In this regard, this paper proposes an object detection algorithm, called DDE‐Net, that does not use multi‐level feature fusion and only uses single‐level feature for optimization. The key component in it: the dense dilated encoder, which encourages dense information exchange of features between different spatial scales. This paper presents extensive experiments, and DDE‐Net shows strong performance compared to that of other popular models on the PASCAL VOC and on the COCO2017 dataset. On the COCO2017 dataset, the authors' DDE‐Net achieves comparable results with its feature pyramids counterpart RetinaNet, while applying the same backbone with smaller params and GFLOPs than RetinaNet. With an image size of 512 × 512, DDE‐Net achieves 37.3 AP running at 81 fps on 2080 Ti. [ABSTRACT FROM AUTHOR]

BACKGROUND: Here, we investigated the control performance of extractive distillation intensified with 'feed split' (FS) technique – a process intensification technique that has not been widely applied to extractive distillation. Today, only a handful of studies have been reported on this topic, with only one focusing on the control performance and reporting the significant trade‐off between the steady‐state and dynamic performances. Nonetheless, the previous control study was based on the complex double column FS configuration. Recently, a new triple column FS configuration was reported (Sep. Purif. Technol. 2022 (297) 121467), but its control performance was not investigated. Hypothetically, the triple column FS configuration is less complex and does not involve any column integration and thus, may demonstrate a better dynamic performance. This study analyzed the control performances of the triple column FS configuration and the conventional configuration for the binary azeotropic separation of tetrahydrofuran and ethanol. RESULTS: Two types of control structures were examined for both configurations, i.e., the basic temperature control structure and the different feed forward temperature control schemes. The best control structure from each configuration is compared and findings showed that the conventional configuration provides better controllability performance. CONCLUSION: Our results suggested that the conventional configuration can bring the product qualities closer to their setpoint, while providing a lower transient deviation. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Significantly enhanced dielectric constant and energy storage density positively facilitate miniaturising dielectric capacitors for various applications in electronics and electrical devices. Herein, a fluoropolymer is coated on BaTiO3 (BT) nanoparticles to form a core–shell structure (BT@PF80), which is used as additional dipoles to enhance the dielectric constant and energy density of polymer nanocomposites. Characterizations with various techniques show uniform dispersion of nanoparticles and good compatibility of interfaces in polymer nanocomposites. Furthermore, the dielectric constant increases from 7.85 of neat polymer to 9.43 of the nanocomposites filled with BT@PF80 while the dielectric loss further decreases from 0.05 to 0.04 at 1 KHz. In addition, 7.79 J cm−3 of energy density is achieved at the nanocomposites filled with BT@PF80, which is 2.65 times higher than that of the neat polymer. This work presents a simple and effective means to enhance dielectric constant and energy density, which tends to fertilize the fabrications of polymer dielectrics for electric energy storage. [ABSTRACT FROM AUTHOR]

Background: Here we analysed the possibility of improving the sustainability performance for the recovery of dichloromethane and methanol from a binary azeotropic mixture using different energy‐intensified extractive distillation‐based processes: side‐stream extractive distillation (SSED), thermally coupled extractive distillation (TCED), and extractive dividing wall column (EDWC). The sustainability performance of the different processes was analysed based on three main factors: total annual cost (TAC), CO2 emissions, and condition number. Results: The EDWC was found to give the best improvement in terms of TAC and CO2 emissions by about 18% and 21%, relative to conventional extractive distillation (CED). These however were traded‐off by the increase in conditional number (CN) by 186 times, signifying a complex dynamic characteristic for the EDWC. Thus, the SSED was suggested as an alternative sustainable option as it also provides significant improvement in TAC and CO2 emissions by about 11%, and 18% with respect to the CED, whilst providing the least reduction in operational controllability, as evidenced by the marginal increase in the CN of about 1.5 times. We also investigated the dynamic performance of the SSED and found that the SSED provides identical dynamic performance in handling both ±10% throughput and ±5% feed composition disturbances as those of the CED. Conclusion: Among the different processes, SSED is the best sustainable alternative that provides compromised steady‐state (i.e. TAC and CO2 emissions) and dynamic (i.e. control) performance for the recovery of dichloromethane and methanol. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Objectives. Osteoarthritis is the leading disease of joints worldwide. Osteoarthritis may be treated by exosomes derived from Runx2-overexpressed bone marrow mesenchymal stem cells (R-BMSCs-Exos). R-BMSCs-Exos would promote the proliferation, migration, and phenotypic maintenance of articular chondrocytes. Methods. BMSCs were transfected with and without Runx2. Exosomes derived from BMSCs and R-BMSCs (BMSCs-Exos and R-BMSCs-Exos) were isolated and identified. Proliferation, migration, and phenotypic maintenance were determined in vitro and compared between groups. The mechanism for activation of Yes-associated protein (YAP) was investigated using small interfering RNA (siRNA). The exosomes' preventive role was determined in vivo using Masson trichrome and immunohistochemical staining. Results. R-BMSCs-Exos enhance the proliferation, migration, and phenotypic maintenance of articular chondrocytes based on the YAP being activated. R-BMSCs-Exos prevent knee osteoarthritis as studied in vivo through a rabbit model. Conclusions. Findings emphasize the efficacy of R-BMSCs-Exos in preventing osteoarthritis. Potential source of exosomes is sorted out for the advantages and shortcomings. The exosomes are then modified based on the molecular mechanisms to address their limitations. Such exosomes derived from modified cells have the role in future therapeutics. [ABSTRACT FROM AUTHOR]

Numerous ingenious top‐down methods have opened a new door to the extensive research of 2D crystals. In this paper, a novel "differential‐temperature exfoliation technology" is proposed to synthesize 2D few‐layer MoS2. Several characterizations are conducted for discussion. The spectroscopic, optical, and purification capacity of the as‐exfoliated layered structures is further studied systematically. This research provides insights into the novel top‐down production and the related potential for environmental protection of few‐layer MoS2. [ABSTRACT FROM AUTHOR]

Cottonseed meal (CSM) and cottonseed oil (CSO), two cottonseed products, are rich in protein and lipids, respectively, but their use is limited by antinutritional factors in the products. This study investigated the effect of different dietary levels of CSM and CSO supplementation on the laying performance and egg quality of laying hens. A total of 162 24‐week‐old Hy‐Line brown laying hens were randomly assigned to diets supplemented with 0, 6%, or 12% CSM and 0, 2%, or 4% CSO in a 3 × 3 factorial design. During the 8‐week feeding trial, laying performance and egg quality parameters were measured weekly. Furthermore, a texture profile analysis (TPA) of the egg yolks was conducted, and the fatty acid profiles and protein composition of the yolks were measured to further determine egg quality. CSM supplementation decreased (p < 0.01) egg production and feed efficiency and increased (p < 0.01) yolk color, eggshell rate, and shell thickness, but had no significant effects on the TPA parameters, fatty acid profiles, and protein components of egg yolks. CSO supplementation resulted in decreases (p < 0.01) in egg production, egg weight, and feed efficiency and an increase (p < 0.01) in yolk color. In addition, CSO supplementation with two weeks of cold storage changed the physical properties of boiled egg yolks, as indicated by increased (p < 0.01) hardness, springiness, cohesiveness, and chewiness. Furthermore, 4% CSO supplementation increased the ratio of saturated/monounsaturated fatty acids (SAFA/MUFA) and the protein content of egg yolks, which was accompanied by a modified protein composition. These results indicate that CSM supplementation reduces laying performance and egg quality, and CSO supplementation decreases laying performance and results in egg yolk hardening by modifying its components. [ABSTRACT FROM AUTHOR]

Tau hyperphosphorylation is a typical pathological change in Alzheimer's disease (AD) and is involved in the early onset and progression of AD. Epigenetic modification refers to heritable alterations in gene expression that are not caused by direct changes in the DNA sequence of the gene. Epigenetic modifications, such as noncoding RNA regulation, DNA methylation, and histone modification, can directly or indirectly affect the regulation of tau phosphorylation, thereby participating in AD development and progression. This review summarizes the current research progress on the mechanisms of epigenetic modification associated with tau phosphorylation. [ABSTRACT FROM AUTHOR]

The separation of ternary nonideal systems with multi‐azeotrope is very important because they are often found in the waste of chemical and pharmaceutical industries, which is much more difficult due to the formation of multi‐azeotrope and distillation boundary. We propose a systematic procedure for design and control of a triple‐column pressure‐swing distillation for separating ternary systems with three binary minimum azeotropes. This procedure involves thermodynamic insights, a two‐step optimization method, and effective control strategy. The separation of tetrahydrofuran (THF)/ethanol/water is used to illustrate the capability of the proposed procedure. It is found that the pressure limits in columns can be determined through the analysis of residue curve maps, distillation boundary, and isovolatility curves. The optimal triple‐column pressure‐swing distillation is generated with the minimum total annual cost (TAC) of $2.181 × 106 in sequence A. The operating conditions are well controlled approaching their desired specifications in an acceptable time when disturbances occur. © 2019 American Institute of Chemical Engineers AIChE J, 65: 1281–1293, 2019 [ABSTRACT FROM AUTHOR]

With the shortage of common vegetable fat sources, such as soybean oil (SBO), it is urgent to find alternative oil sources for broiler producers. The objective of this study was to evaluate the potential of refined cottonseed oil (CSO) as a replacement for SBO in broiler diets. A total of 180 chickens at 1 d of age were randomly assigned to five treatments of six replicates. One treatment was the basal diet (control), and the other four experimental diets were formulated from the basal diet by replacing (w/w) 25%, 50%, 75%, and 100% of the SBO with refined CSO (only containing 0.2% cyclopropenoid fatty acids, and no free gossypol was detected). At the end of week 6, blood samples were obtained from the jugular vein and the breast muscle was aseptically isolated from two birds per replicate. The results showed that substitution of CSO for low‐level SBO had no significant effect (p > 0.05) on broiler performance during the starter period (week 1–3), while 50% level of CSO inclusion significantly increased (p < 0.05) ADG and improved FCR compared with the control group during the finisher period (week 4–6). Broilers fed 100% CSO diets had lower (p < 0.05) levels of serum total protein (TP), albumin (ALB), cholesterol (CHO) concentrations, and serum alkaline phosphatase (AKP) activity than that of the control broilers. Furthermore, the serum antioxidant status appeared to be enhanced by CSO. Additionally, high levels of CSO (75 and 100%) significantly increased the proportions of C14:0 and C18:0 but decreased the proportions of C18:1n9t, C18:2n6c, and ∑ n‐6 polyunsaturated fatty acids in breast muscles of broilers. Overall, the SBO could be replaced with refined CSO up to 50% in diets for broilers without adversely affecting the performance, liver functions, and breast muscle fatty acid composition of these broilers. The objective of this study was to evaluate the potential of refined cottonseed oil (CSO) as a replacement for soybean oil (SBO) in broiler diets. The results showed that replacing 50% of SBO (w/w) with refined CSO in the basal diet increased broiler growth performance during the finisher period. Meanwhile, refined CSO supplementation also enhanced the serum antioxidant status. However, dietary high‐level refined CSO increased the proportions of saturated fatty acids but decreased the unsaturated fatty acids (including n‐6 PUFAs) in breast muscles of broilers. Overall, the SBO could be replaced with refined CSO up to 50% in diets for broilers without adverse effects. [ABSTRACT FROM AUTHOR]

Staphylokinase (SAK) is a 15.5-kDa protein from Staphylococcus aureus that activates plasminogen by forming a 1 : 1 complex with plasmin. Recombinant SAK has been shown in clinical trials to induce fibrin-specific clot lysis in patients with acute myocardial infarction. However, SAK elicits high titers of neutralizing antibodies. Biochemical and protein engineering studies have demonstrated the feasibility of generating SAK variants with reduced antigenicity yet intact thrombolytic potency. Here, we present X-ray crystallographic evidence that the SAK(S41G) mutant may assume a dimeric structure. This dimer model, at 2.3-Å resolution, could explain a major antigenic epitope (residues A72–F76 and residues K135-K136) located in the vicinity of the dimer interface as identified by phage-display. These results suggest that SAK antigenicity may be reduced by eliminating dimer formation. We propose several potential mutation sites at the dimer interface that may further reduce the antigenicity of SAK. [ABSTRACT FROM AUTHOR]