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The roofs of heritage buildings are subject to long-term degradation, resulting in poor heat insulation, heat regulation, and water leakage prevention. Researchers have predominantly employed feature-based traditional machine learning methods or individual deep learning techniques for the detection of natural deterioration and human-made damage on the surfaces of heritage building roofs for preservation. Despite their success, balancing accuracy, efficiency, timeliness, and cost remains a challenge, hindering practical application. The paper proposes an integrated method that employs a convolutional autoencoder, thresholding techniques, and a residual network to automatically detect anomalies on heritage roof surfaces. Firstly, unmanned aerial vehicles (UAVs) were employed to collect the image data of the heritage building roofs. Subsequently, an artificial intelligence (AI)-based system was developed to detect, extract, and classify anomalies on heritage roof surfaces by integrating a convolutional autoencoder, threshold techniques, and residual networks (ResNets). A heritage building project was selected as a case study. The experiments demonstrate that the proposed approach improved the detection accuracy and efficiency when compared with a single detection method. The proposed method addresses certain limitations of existing approaches, especially the reliance on extensive data labeling. It is anticipated that this approach will provide a basis for the formulation of repair schemes and timely maintenance for preventive conservation, enhancing the actual benefits of heritage building restoration.

The antibacterial activity and mechanism of juglone from walnut green husk against Escherichia coli were studied. E. coli was treated with juglone from walnut green husk in different concentrations. The minimum inhibitory concentration (MIC) of juglone was determined, and its effect on the growth curve, cell membrane relative conductivity, fluorescence emission spectrum, biofilm formation, cell viability, protein formation and genomic DNA and RNA synthesis of E. coli were investigated. The results showed that juglone had effective antibacterial activity against E. coli with an MIC value of 0.062 5 mg/mL. The relative conductivity of E. coli cell membrane increased after treatment with different concentrations of juglone, indicating that juglone destroyed the integrity of the cell membrane and increased the permeability. The results of fluorescence emission spectroscopy showed that juglone was able to interact with membrane proteins to change the membrane structure of E. coli cells. The results of crystal violet and resazurin staining showed that juglone could weaken the respiration of E. coli by inhibiting the formation of E. coli biofilms, thereby inhibiting its viability. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and E. coli genome synthesis analysis showed that juglone inhibited the expression of protein, DNA and RNA in E. coli. Through molecular docking, it was found that juglone can bind to the grooves of genomic DNA, thereby changing its secondary structure and morphology. In summary, juglone has a good inhibitory effect on E. coli, and can therefore be used as a natural antibacterial agent in the prevention and control of foodborne E. coli.

In this study, the total phenol and flavonoid contents of the ethanol extract of green walnut husks were determined as (21.71 ± 0.98) and (22.16 ± 0.45) mg/g, respectively. Using ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS) and high performance liquid chromatography (HPLC), nine major compounds in the extract were identified including quercitrin, avicularin, astragalin, hyperoside, isoquercetin, quercetin, caffeic acid, ferulic acid and juglone. The extract had a protective effect against 2,2’-azobis-2-methyl-propanimidamide dihhydrochloride (AAPH)-induced oxidative damage to biological macromolecules. The extract at 1 mg/mL had a significant protective effect against oxidative damage to bovine serum albumin (BSA), and at 0.5 mg/mL, it could protect plasmid DNA from oxidative damage. The extracts had antibacterial activity against Escherichia coli, which could increase the permeability of the bacterial cell membrane and destroy its integrity, thereby resulting in the leakage of intracellular nucleic acid and proteins. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) results showed that the damage to cellular proteins could be another antibacterial mechanism of the extract. In addition, the extract inhibited the respiration of E. coli, and the percent increase in respiration rate with the extract alone compared to that with its combination with trisodium phosphate was the lowest. The extract significantly reduced the activity of glucose-6-phosphate dehydrogenase. Therefore, it can be inferred that the extract exerts an antibacterial effect mainly by participating in regulating the respiratory metabolism of the pentose phosphate pathway.

In this study, an antioxidant peptide was purified from the protein hydrolysate of germinated chickpea by Sephadex column chromatography, and its antioxidant activities were evaluated by determining free radical scavenging capacity, reducing power, lipid oxidation inhibitory effect and protective effect against free radical-induced damage to proteins and DNA. The purified peptide was identified and synthesized to verify its antioxidant activities, and the safety of the synthetic peptide was predicted. The results showed that the antioxidant peptide had good free radical scavenging ability and reducing power, significantly inhibited the autooxidation of linoleic acid, and protected against protein and DNA damage induced by free radicals. It was predicted that the synthetic peptide had no toxicity or allergenicity. In conclusion, the protein hydrolysate of germinated chickpea has antioxidant capacity and can be used to prepare antioxidant peptides, which will improve the utilization value of chickpea.

The carbon emission trading scheme (ETS) is an essential policy tool for accomplishing Chinese carbon targets. Based on the Chinese provincial panel data from 2003 to 2019, an empirical study is conducted to measure the effects of carbon emission reduction and spatial spillover effect by adopting the difference-in-differences (DID) model and spatial difference-in-differences (SDID) model. The research findings show that: 1) The ETS effectively reduced the total carbon emissions as well as emissions from coal consumption; 2) such effects come mainly from the reduction of coal consumption and the optimization of energy structure, rather than from technological innovation and optimization of industrial structure in the pilot regions; and 3) the ETS pilot regions have a positive spatial spillover effect on non-pilot regions, indicating the acceleration effect for carbon emission reduction. Geographic proximity makes the spillover effect decrease due to carbon leakage.

This paper describes a smart fault tackling strategy based on power flow transfer entropy (PFTE) for AC three-phase-to-ground (TPG) faults in the multi-terminal HVDC (MTDC) wind power integration system. The fault characteristics and transient energy transfer of different positions and properties are analyzed. Then, a double integral discrimination method based on PFTE is proposed to further distinguish the fault property. Considering the power flow balance, an adaptive coordination strategy of wind farms and energy dissipation resistors is proposed to deal with different AC faults. Finally, a smart fault-tackling strategy based on PFTE for AC three-phase-to-ground (TPG) faults in the MTDC wind power integration system is proposed. Under the proposed smart fault-tackling strategy, the MTDC wind power integration system achieves uninterrupted operation during any AC TPG fault at the receiving end. The experiment results confirm the applicability of the proposed fault-tackling strategy.

In recent years, with the development of high voltage direct current (HVDC) transmission technology, wind power integration with modular multiple converter-HVDC (MMC-HVDC) has been widely researched and applied. However, the conventional control methods on wind power integration cannot match the flexibility needing of loads. In this paper, a wind power integration system with permanent magnet direct-drive wind farm and full-bridge MMC is proposed. It has the characteristics of independent control of AC and DC current, which can realise the stable operation of the system under low DC voltage, so that to effectively avoid the accident of the wind turbine cut-off caused by the load reduce. When the DC voltage drops, the system can maintain a constant AC voltage at the wind power integration point, so that the wind farm can operate normally. Finally, the simulation results in PSCAD/EMTDC show that the proposed system and its control strategy are correct.

Photoluminescent liquid crystals (PLLCs) have attracted significant attention owing to their broad applicability in thermosensing and PL switching. Extensive efforts have been made to develop bistolane-based PLLCs containing flexible units at both molecular terminals, and it has been revealed that their PL behavior can switch with the phase transition between the crystalline and LC phases. Although slight modulation of the flexible unit structure dramatically alters the LC and PL behaviors, few studies into the modification of the flexible units have been conducted. With the aim of achieving dynamic changes in their physical behaviors, we developed a family of bistolane derivatives containing a simple alkyl or a fluoroalkyl flexible chain and carried out a detailed systematic evaluation of their physical behaviors. Bistolanes containing a simple alkyl chain showed a nematic LC phase, whereas switching the flexible chain in the bistolane to a fluoroalkyl moiety significantly altered the LC phase to generate a smectic phase. The fluoroalkyl-containing bistolanes displayed a stronger deep blue PL than their corresponding non-fluorinated counterparts, even in the crystalline phase, which was attributed to the construction of rigid molecular aggregates through intermolecular F···H and F···F interactions to suppress non-radiative deactivation.

The structure of the title compound, C16H15ClO4, contains aryl rings which are inclined by 75.6 (1)° to each other. It displays intramolecular O—H...O hydrogen bonding between the 2-hydroxy and carbonyl groups, forming a six-membered ring. Furthermore, the 4-hydroxy group, acting as a hydrogen-bond donor, is bound to the O atom of the 2-hydroxy group of another molecule.

Understanding olfaction at the molecular level is challenging due to the lack of crystallographic models of odorant receptors (ORs). To better understand the molecular mechanism of OR activation, we focused on chiral (R)-muscone and other musk-smelling odorants due to their great importance and widespread use in perfumery and traditional medicine, as well as environmental concerns associated with bioaccumulation of musks with estrogenic/antiestrogenic properties. We experimentally and computationally examined the activation of human receptors OR5AN1 and OR1A1, recently identified as specifically responding to musk compounds. OR5AN1 responds at nanomolar concentrations to musk ketone and robustly to macrocyclic sulfoxides and fluorine-substituted macrocyclic ketones; OR1A1 responds only to nitromusks. Structural models of OR5AN1 and OR1A1 based on quantum mechanics/ molecular mechanics (QM/MM) hybrid methods were validated through direct comparisons with activation profiles from sitedirected mutagenesis experiments and analysis of binding energies for 35 musk-related odorants. The experimentally found chiral selectivity of OR5AN1 to (R)- over (S)-muscone was also computationally confirmed for muscone and fluorinated (R)-muscone analogs. Structural models show that OR5AN1, highly responsive to nitromusks over macrocyclic musks, stabilizes odorants by hydrogen bonding to Tyr260 of transmembrane α-helix 6 and hydrophobic interactions with surrounding aromatic residues Phe105, Phe194, and Phe207. The binding of OR1A1 to nitromusks is stabilized by hydrogen bonding to Tyr258 along with hydrophobic interactions with surrounding aromatic residues Tyr251 and Phe206. Hydrophobic/nonpolar and hydrogen bonding interactions contribute, respectively, 77% and 13% to the odorant binding affinities, as shown by an atom-based quantitative structure-activity relationship model. [ABSTRACT FROM AUTHOR]

The geology and tectonics in the eastern margin of Tibetan Plateau are complex. The main tectonic framework is composed of blocks and faults. Using discontinuous global positioning system survey data for 2008-2014, the velocity field for the Eurasia reference framework was obtained. Based on the velocity field, the present-day velocities of the blocks and boundary faults were estimated. The results reveal that the movement rates of the Chuan-Qing, South China, Chuan-Dian and Indo-China blocks are (17.02±0.60) mm/a, (8.77±.51) mm/a, (13.85±.31) mm/a and (6.84 ± 0.74) mm/a, respectively, and their movement directions are 99.5°, 120.3°, 142.9° and 153.3°, respectively. All blocks exhibit clockwise rotation. The displacement rates of the Xianshuihe, Longmenshan, Anninghe, Zemuhe, Xiaojiang and Red River faults are (7.30±1.25-8.30±1.26) mm/a, (10.07±0.97-11.79±0.89) mm/a, (0.96±0.74-2.98±1.73) mm/a, (2.03±0.49-3.20±0.73) mm/a, (3.45±0.40-6.02±0.50) mm/a and (6.23±0.56) mm/a, respectively. The Xianshuihe, Anninghe, Zemuhe and Xiaojiang faults show left-lateral strike-slip movement, while the Longmenshan and Red River faults show right-lateral strike-slip. These characteristics of the blocks and faults are related to the particular tectonic location and dynamic mechanism. [ABSTRACT FROM AUTHOR]

The Wenchuan earthquake has altered the crustal motion characteristics in the eastern margin of the Tibetan Plateau and adjacent regions. Using discontinuous GPS survey data for 2008-2012, the velocity field for the Eurasia reference framework has been obtained, and the general trend of contemporary crustal motion after the occurrence of the Wenchuan earthquake has been studied. In addition, using the velocity field, the block movement velocity has been estimated by least-squares fitting. Furthermore, the properties and displacement rates of main faults have been obtained from the differences in velocity vectors of the blocks on both sides of the faults. The results reveal that there are no obvious changes in the general characteristics of crustal motion in this area after the Wenchuan earthquake. The earthquake mainly changed the rate of the movement of the Chuan-Qing block and caused variation in the movement direction of the South China block. The effect of the earthquake on faults is mainly reflected in variations in fault displacement velocity; there is no fundamental change in the properties of fault activity. The displacement rates of the Xianshuihe fault decreased by 3-4 mm/a, the Longmenshan fault increased by 9-10 mm/a, and the northern segment of the Anninghe fault increased by approximately 9 mm/a. Furthermore, the displacement rates of the Minjiang, Xueshan, Huya, Longquanshan, and Xinjin faults increased by 2-3 mm/a. This implies that the effects of the Wenchuan earthquake on crustal movement can mainly be observed in the Chuan-Qing, South China, and N-Chuan-Dian blocks and their internal faults, as well as the Xianshuihe and Longmenshan faults and the northern section of the Anninghe fault. The reason for this is that the Wenchuan earthquake disturbed the kinematic and dynamic balance in the region. [ABSTRACT FROM AUTHOR]

Background: Evidence suggests that the consumption of anthocyanin-rich foods beneficially affects cardiovascular health; however, the absorption, distribution, metabolism, and elimination (ADME) of anthocyanin-rich foods are relatively unknown. Objective: We investigated the ADME of a 13C5-labeled anthocyanin in humans. Design: Eight male participants consumed 500 mg isotopically labeled cyanidin-3-glucoside (6,8,10,3',5'-13C5-C3G). Biological samples were collected over 48 h, and 13C and 13C-labeled metabolite concentrations were measured by using isotope-ratio mass spectrometry and liquid chromatography-tandem mass spectrometry. Results: The mean ± SE percentage of 13C recovered in urine, breath, and feces was 43.9 ± 25.9% (range: 15.1-99.3% across participants). The relative bioavailability was 12.38 ± 1.38% (5.37 ± 0.67% excreted in urine and 6.91 ± 1.59% in breath). Maximum rates of 13C elimination were achieved 30 min after ingestion (32.53 ± 14.24 µg 13C/h), whereas 13C-labeled metabolites peaked (maximum serum concentration: 5.97 ± 2.14 µmol/L) at 10.25 ± 4.14 h. The half-life for 13C-labeled metabolites ranged between 12.44 ± 4.22 and 51.62 - 22.55 h. 13C elimination was greatest between 0 and 1 h for urine (90.30 ± 15.28 µg/h), at 6 h for breath (132.87 ± 32.23 µg/h), and between 6 and 24 h for feces (557.28 ± 247.88 µg/h), whereas the highest concentrations of Relabeled metabolites were identified in urine (10.77 ± 4.52 µmol/L) and fecal samples (43.16 ± 18.00 µmol/L) collected between 6 and 24 h. Metabolites were identified as degradation products, phenolic, hippuric, phenylacetic, and phenylpropenoic acids. Conclusion: Anthocyanins are more bioavailable than previously perceived, and their metabolites are present in the circulation for ≤48 h after ingestion. This trial was registered at clinicaltrials.gov as NCT01106729. [ABSTRACT FROM AUTHOR]

We have developed a nanotube-based colorimetric probe using multiwalled carbon nanotubes (MWNTs), anti-immunoglobulin G (anti-IgG), and horseradish peroxidase (HRP). The probe was used as an alternative to conventional colorimetric conjugates to obtain amplified signals in a sandwich-type immunoassay for ataxia telangiectasia mutated (ATM), a potential biomarker for radiation doses and cancers. Results show that the MWNT-based probe colorimetry was 5000 times more sensitive than a conventional ELISA, while its concentration range was 10?000 times wider than that of the latter. Its limit of detection (LOD) was 0.2 fg/mL (54 aM, ~32 molecules in 1 μL samples). Control experiments showed that detection of ATM molecules at the picogram-level could still be achieved in samples that contained protein makers present at more than 100 times the ATM concentration, demonstrating the high specificity of the technique. The MWNT-based probe also has the potential to become a universal probe for colorimetric assays of most protein markers because it can recognize the associated rabbit polyclonal antibodies. [ABSTRACT FROM AUTHOR]

The reaction of 2,4-bis(phenyl)-1,3-diselenadiphosphetane-2,4-diselenide (Woollins’ Reagent, WR) with phenylalkylcyanamides (RR′NCN, R = PhCH2CH2, R′ = CH3 and R = PhCH2CH2CH2, R′ = H) in refluxing toluene led to novel heterocyclic selenazadiphospholaminediselenides 1 and 2 (43% and 42% yields), the latter being hydrolyzed to the unusual zwitterionic carbamidoyl(phenyl)phosphinodiselenoic acids 3 and 4 in excellent yields (96% and 98%). [ABSTRACT FROM AUTHOR]