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• Stress singularity, displacement and strain discontinuities were described by XFEM. • Crack propagation criterion for heterogeneous materials was proposed. • Failure pattern of microcapsule including rupture or debonding were realized. • Predictive model for microcapsule cracking was proposed based on XFEM and ML. The cracking behavior of microcapsules in cement-based self-healing materials is essential for releasing healing agents during crack healing. In this study, the extended finite element method and machine learning were combined to predict the competitive behavior of microcapsule debonding and rupture. The fracture criterion based on energy was developed to investigate the interaction of the crack and microcapsule for heterogeneous materials. The artificial neural network was trained on 1031 datasets from extended finite element method (XFEM) simulations, and the mean square error (MSE) was 3.7E-3 and the overall R 2 was 0.94 in 16 epochs. With the proposed model, the cracking behavior of microcapsules can be judged accurately and instantly without extensive computation, which can help clarify the release condition of healing agents encapsulated in microcapsules so as to guide the design of intelligent composite materials. [ABSTRACT FROM AUTHOR]

• NH 4 HCO 3 possesses the capacity of extraction and precipitation towards calcium. • The regeneration of NH 4 HCO 3 realizes the catalyst effect and continuous supply. • The regeneration potential of NH 4 HCO 3 increased with the increase of NH 3 ·H 2 O. Repeatable self-healing at the same cracking site is one of the essential issues in self-healing concrete. The inorganic admixture ammonium bicarbonate (NH 4 HCO 3) was proposed as the primary healing agent in this study to achieve repeatable self-healing. Among ammonium carbamate (NH 2 COONH 4), NH 4 HCO 3 , ammonium acetate (CH 3 COONH 4) and calcium hydroxide (Ca(OH) 2), the molar ratio of precipitation reaction and the effect of calcium extraction were determined. Whether before or after the self-healing, ammonia water (NH 3 ·H 2 O) invariably exists in the products and will be carbonised to regenerate NH 4 HCO 3 , which was verified by Fourier transform infrared (FT-IR). The proposed self-healing solution achieves a two-in-one strategy for calcium extraction and carbon sequestration in response to the global strategy for carbon neutrality. Self-healing experiments have been performed. The results suggested that the healing efficiency of the crack area of the tri-component (NH 2 COONH 4 , NH 4 HCO 3 and CH 3 COONH 4) is up to five times higher than that of the control group. Three cycles of self-healing in the simulated system and actual crack environment concluded that the regeneration potential of NH 4 HCO 3 could be enhanced after the completion of more cyclic self-healing processes due to the increasing amount of NH 3 ·H 2 O at the same cracking site. [ABSTRACT FROM AUTHOR]

Opioid receptors play an important role in both behavioral and mood functions. Based on the structural modification of LY2456302, a series of aminobenzyloxyarylamide derivatives were designed and synthesized as κ opioid receptor antagonists. The κ opioid receptor binding ability of these compounds were evaluated with opioid receptors binding assays. Compounds 1a-d showed high affinity for κ opioid receptor. Especially for compound 1c , exhibited a significant K i value of 15.7 nM for κ opioid receptor binding and a higher selectivity over μ and δ opioid receptors compared to (±)LY2456302. In addition, compound 1c also showed potent κ antagonist activity with κ IC 50 = 9.32 nM in [ 35 S]GTP-γ-S functional assay. The potential use of the representative compounds as antidepressants was also investigated. The most potent compound 1c not only exhibited potent antidepressant activity in the mice forced swimming test, but also displayed the effect of anti-anxiety in the elevated plus-maze test. [ABSTRACT FROM AUTHOR]

Real world complex systems have multiple levels of relationships and in many cases, they need to be modeled as multiplex networks where the same nodes can interact with each other in different layers, such as social networks. However, social relationships only appear at prescribed times so the temporal structures of edge activations can also affect the dynamical processes located above them. To consider both factors are simultaneously, we introduce multiplex temporal networks and propose three different walk strategies to investigate the concurrent dynamics of random walks and the temporal structure of multiplex networks. Thus, we derive analytical results for the multiplex centrality and coverage function in multiplex temporal networks. By comparing them with the numerical results, we show how the underlying topology of the layers and the walk strategy affect the efficiency when exploring the networks. In particular, the most interesting result is the emergence of a super-diffusion process, where the time scale of the multiplex is faster than that of both layers acting separately. [ABSTRACT FROM AUTHOR]

The human immunodeficiency virus-1 (HIV-1) envelope glycoprotein (Env) is comprised of non-covalently associated gp120/gp41 subunits that form trimeric spikes on the virion surface. Upon binding to host cells, Env undergoes a series of structural transitions, leading to gp41 rearrangement necessary for fusion of viral and host membranes. Until now, the prefusion state of gp41 ectodomain (e.gp41) has eluded molecular and structural analysis, and thus assessment of the potential of such an e-gp41 conformer to elicit neutralizing antibodies has not been possible. Considering the importance of gp120 amino (C1) and carboxyl (C5) segments in the association with e-gp41, we hypothesize that these regions are sufficient to maintain e-gp41 in a prefusion state. Based on the available gp120 atomic structure, we designed several truncated gp140 variants by including the C1 and C5 regions of gp120 in a gp41 ectodomain fragment. After iterative cycles of protein design, expression and characterization, we obtained a variant truncated at Lys665 that stably folds as an elongated trimer under physiologic conditions. Several independent biochemical/biophysical analyses strongly suggest that this mini-Env adopts a prefusion e-gp41 configuration that is strikingly distinct from the postfusion trimer-of-hairpin structure. Interestingly, this prefusion mini-Env, lacking the fragment containing the 2F5/4E10 neutralizing monoclonal antibody binding sites, displays no detectable HIV-neutralizing epitopes when employed as an immunogen in rabbits. The result of this immunogenicity study has important implications for HIV-1 vaccine design efforts. Moreover, this engineered mini-Env protein should facilitate three-dimensional structural studies of the prefusion e-gp41 and serve to guide future attempts at pharmacologic and immunologic intervention of HIV-1. [ABSTRACT FROM AUTHOR]

Investigates the disulfide-forming pathway of a single-chain porcine insulin precursor and studies the folding pathway of human proinsulin (HPI) in vitro. Quenching of the oxidized refolding process of HPI; Isolation and characterization of intermediates with disulfide bridges; Initiation site for the folding of porcine and human proinsulin.

The phytochemical study of the aerial part of Mesona chinensis led to the isolation of five new caffeic acid oligomers (1 – 5), as well as four known analogues (6 – 9). The structures of the new compounds including their absolute configurations were elucidated by comprehensive spectroscopic analysis, chemical method, and quantum-chemical electronic circular dichroism (ECD) calculation. Among the isolates, compound 7 showed significant in vitro antiviral activity on respiratory syncytial virus (RSV). Unlabelled Image [ABSTRACT FROM AUTHOR]

• Opioid receptors are a family of G-protein coupled receptors and involved in multiple physiological activities. • A series of κ opioid receptor antagonists were designed and synthesized based on the scaffold of aminobenzyloxyarylamide. • All target compounds were evaluated in radioligand binding assays for opioid receptor binding affinity. • Compound 1c exhibited high affinity for KOR. • The selectivity of compound 1c for KOR was improved, compared with (±)LY2456302. Aminobenzyloxyarylamide derivatives 1a-i and 2a-t were designed and synthesized as novel selective κ opioid receptor (KOR) antagonists. The benzoyl amide moiety of LY2456302 was changed into N -hydroxybenzamide and benzisoxazole-3(2 H)-one to investigate whether it could increase the binding affinity or selectivity for KOR. All target compounds were evaluated in radioligand binding assays for opioid receptor binding affinity. These efforts led to the identification of compound 1c (κ K i = 179.9 nM), which exhibited high affinity for KOR. Moreover, the selectivity of KOR over MOR and DOR increased nearly 2-fold and 7-fold, respectively, compared with (±)LY2456302. [ABSTRACT FROM AUTHOR]

• A novel self-healing aggregate meeting engineering specifications is developed. • Self-healing aggregate preserved concrete's strength and permeability. • The self-healing concrete achieves satisfactory healing performance and efficiency. • The healing mechanism of the self-healing system in this study is illustrated. To efficiently heal concrete without compromising mechanical strength, this research investigated an easy approach to synthesis self-healing aggregate. The findings indicate that integrating self-healing aggregates preserved the mechanical strengths, equivalent workability, and permeability of the concrete. Image analysis revealed a healing rate exceeding 80 % for crack areas when the crack width was less than 400 μm, with superior healing product generation within 8 mm crack depth. By day 28, the healing rate for flexural strength reached 72.8 %, and impermeability recovered by 45.4 %. These results underscore the potential for the realization of self-healing concrete suitable for practical deployment. [ABSTRACT FROM AUTHOR]

• DAA has both repetitive self-healing and autonomous compensation for shrinkage. • The dual functions of DAA are both independent and synergistic of each other. • Increasing available extracted calcium by the extrinsic supplement. A difunctional artificial aggregate (DAA) was developed to address autogenous shrinkage caused by self-desiccation of concrete during early hydration in this study. Through in-situ combination with a tri-component healing agent, comprising ammonium acetate CH 3 CCONH 4 , ammonium bicarbonate NH 4 HCO 3 , and ammonium carbamate NH 2 COONH 4 , repetitive self-healing for cracks can be achieved. The expansion product can provide additional free calcium to enhance the self-healing process. Compensatory self-healing is triggered by exposing the internal tri-component to over-expansion, where both expansion compensation and repetitive self-healing are independent but interact with each other. At a 2% DAA dosage, appropriate compensation for hydration expansion was achieved while maintaining specimen volume integrity. The compensatory self-healing of the 4% group was effective for 60 days, while the 8% group exhibited the lowest self-desiccation effect and densest pore structure. In the twice self-healing experiment involving the 0% and 2% groups, various measurements were taken to evaluate healing efficiency, including sound velocity, compressive strength, and quantitative characterisation of calcium carbonate (CaCO 3). Results showed a higher healing rate for the second self-healing compared to the first (167.13%, 37.76%, and 12.4% compared to 146.05%, 23.36%, and 7.2%, respectively). This confirmed that the self-healing efficiency increased with the regeneration of NH 4 HCO 3 , which increased with the number of self-healings. [ABSTRACT FROM AUTHOR]

This paper develops a novel short-term load forecasting model that hybridizes several machine learning methods, such as support vector regression (SVR), grey catastrophe (GC (1,1)), and random forest (RF) modeling. The modeling process is based on the minimization of both SVR and risk. GC is used to process and extract catastrophe points in the long term to reduce randomness. RF is used to optimize forecasting performance by exploiting its superior optimization capability. The proposed SVR-GC-RF model has higher forecasting accuracy (MAPE values are 6.35% and 6.21%, respectively) using electric loads from Australian-Energy-Market-Operator; it can provide analytical support to forecast electricity consumption accurately. • This paper hybridizes grey catastrophe and random forest with support vector regression for short-term load forecasting. • The proposed model overcomes the drawbacks, including singleness, randomness, low accuracy, and overfitting. • Experimental results reveal that the proposed model has greater forecasting accuracy than three alternative models. [ABSTRACT FROM AUTHOR]

Age-related changes such as increased oxidative stress and DNA damage are important risk factors for Alzheimer's disease (AD). This study aimed to clarify the role of POLD1, the catalytic subunit of DNA polymerase δ, in neurodegeneration symptoms of AD. POLD1 expression levels were evaluated in patients with different neurodegenerative diseases by ELISA, RT-PCR and Western blot analysis. The impairment of cognitive ability in AD patients and senescence-accelerated mouse prone 8 (SAMP8) mice were evaluated by MMSE/MoCA score and Morris water maze (MWM) test. We found that serum concentration and expression levels of POLD1 in lymphocytes were reduced in AD patients. The cognitive impairment in AD patients and SAMP8 mice was associated with reduced POLD1 expression. In addition, POLD1 knockdown led to premature senescence and increased DNA damage in primary neuronal cells of SAMP8 mice. In conclusion, this is the first study suggesting that the deficiency of POLD1 may aggravate AD progression, and POLD1 is a potential diagnostic marker and therapeutic target for AD. [ABSTRACT FROM AUTHOR]

An isolate, designated as ZZY, was obtained from a long-term heavy metals contaminated soil with the potential to remove Cd 2+ . The strain's screening, identification and biosorption characteristics including the effect of initial concentration of metal ions, pH value, biosorption temperature, biosorption time, inoculum size, mineral nutrients, and competing ions on biosorption were studied. Based on morphological observations and 18 S rRNA gene sequence identification, ZZY had affinity to Cunninghamella bertholletiae. The optimum parameters for Cd 2+ biosorption by the strain were: Cd 2+ tolerance of 4 mg/L, pH value of 4, biosorption time of 84 h, biosorption temperature of 35 °C, quantity of added thallus of 6% (v/v), the mineral collaborative concentration of 0.05 g/L (mass of mineral nutrition per liter of medium). In addition, the determination of biosorption sites distribution and the results of Fourier transform infrared spectroscopy (FT-IR) showed that biosorption occurred at the thallus surface, the chief active biosorption sites being O H, C O, and N H. [ABSTRACT FROM AUTHOR]

• A microcapsule fiber-reinforced cement-based composite was prepared. • The best combination of mechanical properties is obtained by range analysis. • The microcapsule content is the main factor influencing the mechanical properties. • SEM/EDS confirmed that the composite has self-healing capacity. This study combined the microcapsule self-healing system with fiber reinforced concrete (FRC), and investigated the effects of microcapsule content, mineral admixture type, mineral admixture content, and fiber type on tensile and compressive strength, ductility, and self-healing properties of the fiber-reinforced microcapsule self-healing cementitious composites by the orthogonal test method. For the uniaxial tensile and cubic compression tests, the optimum tensile strength group consists of a 2.2 mass ratio of GGBS, PE fiber, and no microcapsules. The optimum compressive strength group consists of a 2.2 mass ratio of GGBS, hybrid fiber, and no microcapsules. Microcapsule content and fiber type are the main factors affecting tensile properties, and an increase in the microcapsule content will reduce the tensile strength and compressive strength of the matrix. The optimum tensile strain group consists of 10% microcapsule content and a 2.2 mass ratio of GGBS and PE fiber. The results of the energy-based steady-state crack propagation test show that the fiber type is the most critical factor affecting the ductility, and the tensile ductility of the PE fiber group is higher than that of the PVA fiber group. The scanning electron microscopy/energy dispersive X-ray spectrometry (SEM/EDS) diagram proved the healing effect of the fiber-reinforced microcapsule self-healing cementitious composite. [ABSTRACT FROM AUTHOR]

A novel series of tetrahydroisoquinoline quaternary derivatives 4 were synthesized as peripheral κ-opioid receptor agonists. All the target compounds were evaluated in κ-opioid receptor binding assays, and compounds 4l , 4m , and 4n exhibited high affinity for κ-opioid receptor. Furthermore, compound 4l (κ K i = 0.94 nM) produced potent antinociceptive activity in the mouse acetic acid-induced writhing assay, with lower sedative side effects than the parent compound MB-1c. [ABSTRACT FROM AUTHOR]

Eighteen stilbenes (1 – 18), including six previously undescribed ones (1 – 6), with diverse modification patterns were isolated from the leaves of edible and medicinal plant Cajanus cajan. Among the new isolates, compounds 1 – 3 were initially obtained as three racemic mixtures, which were further resolved into three pairs of optically pure enantiomers, respectively, by chiral HPLC. Besides, compounds 8 , 10 , 11 , and 18 were obtained from C. cajan for the first time. The chemical structures and absolute configurations of the new stilbenes were elucidated unambiguously on the basis of extensive spectroscopic analyses, single crystal X-ray crystallographic study, and quantum chemical electronic circular dichroism (ECD) calculations. In addition, the in vitro anti-inflammatory activities of all isolated stilbenes were evaluated. Compounds 2 , 9 , 10 , 11 , and 14 exerted moderate suppression of nitric oxide (NO) secretion in lipopolysaccharide (LPS)-induced RAW264.7 cells without exhibiting substantial cytotoxicity. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: A series of new cinnamanilides (6–40) were synthesized and their immunosuppressive activity and cytotoxicity were evaluated. Most of the cinnamanilides showed good immunosuppressive activity. Among the synthesized compounds, (Z)-N-(4-bromophenyl)-2-methoxy-3-(4-methoxyphenyl)acrylamide (37) and (Z)-2-methoxy-3-(4-methoxyphenyl)-N-p-tolylacrylamide (38) exhibited potent immunosuppressive activity (IC50 = 1.77 ± 0.33 and 0.94 ± 0.13 μM) without significant cytotoxicity. [Copyright &y& Elsevier]