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Tip leakage flow in turbomachinery inherently generates intense unsteady features, named self-excited unsteadiness, which significantly affects the operating stability, aerodynamic efficiency, and noise but has not been well understood. A zonalized large eddy simulation is employed for a linear cascade, with wall-modeled large eddy simulation active only in the tip region. The simulation is well validated with advantages demonstrated for effectively reducing the computational cost while maintaining an equivalent prediction accuracy in the region of interest. The time-averaged and spatial-spectral characteristics of tip leakage vortex (TLV) structures are systematically discussed. The self-excited unsteady processes of TLV include the tip gap separation, the tip leakage and jet-mainstream interaction, the primary tip leakage vortex (PTLV) wandering motion, and the induced separation near end wall. The Spectral Proper Orthogonal Decomposition (SPOD) is used to examine the dominant frequencies and their coherent structures. It is found that these unsteady features change from a single high frequency to multiple lower frequencies due to the PTLV breakdown. The SPOD and correlation analyses reveal that the self-excited unsteadiness originates initially from unsteady vortex separation in the tip gap and is then fed by the interactions between the tip leakage jet and mainstream. The associated unsteady fluctuations are convected along the tip leakage jet trajectory, causing the wandering motion of PTLV core. Based on the revealed unsteadiness sources, a micro-offset tip design is proposed and shown to be an effective solution to reducing the tip flow unsteadiness. This work improves the understanding of tip-leakage-flow dynamics and informs the control of the associated unsteady fluid oscillation and noise. [ABSTRACT FROM AUTHOR]

Recent studies show that neural networks are vulnerable to backdoor attacks, in which compromised networks behave normally for clean inputs but make mistakes when a pre-defined trigger appears. Although prior studies have designed various invisible triggers to avoid causing visual anomalies, they cannot evade some trigger detectors. In this paper, we consider the stealthiness of backdoor attacks from input space and feature representation space. We propose a novel backdoor attack named sparse backdoor attack, and investigate the minimum required trigger to induce the well-trained networks to make incorrect results. A U-net-based generator is employed to create triggers for each clean image. Considering the stealthiness of the trigger, we restrict the elements of the trigger between −1 and 1. In the aspect of the feature representation domain, we adopt an entanglement cost function to minimize the gap between feature representations of benign and malicious inputs. The inseparability of benign and malicious feature representations contributes to the stealthiness of our attack against various model diagnosis-based defences. We validate the effectiveness and generalization of our method by conducting extensive experiments on multiple datasets and networks. [ABSTRACT FROM AUTHOR]

Flow separations occur in the tip region when the fan is operating at the approach condition. To reduce computational cost without degrading accuracy, the hierarchical modeling approach has been developed to predict such fan flow. This allows both flow and geometry to be treated with various fidelity levels in different zones. To be specific, this is achieved by zonalizing large-eddy simulation (LES) in the fan tip region and modeling downstream stators with low-order blade body forces. This approach provides an accurate and economical prediction of separated fan flows in the stage environment. The predicted fan wake profiles show a reasonably good agreement with the hot-wire measurements considering passage-to-passage variations. Finally, the simulation data are used to assess the isotropic turbulence hypothesis that is made on fan wake in low-order acoustics models. [ABSTRACT FROM AUTHOR]

When multiple bus vehicles send priority requests at a single intersection, the existing fixed-phase sequence control methods cannot provide priority traffic request services for multiphase bus vehicles. In view of the conflict of multiphase bus priority requests at intersections, the priority vehicle traffic sequence is determined, which is the focus of this study. In this paper, a connected vehicle-enabled transit signal priority system (CV-TSPS) has been proposed, which uses vehicle-infrastructure communication function (V2I) technology to obtain real-time vehicle movement, road traffic states, and traffic signal light phase information. By developing a deep Q-learning neural network (DQNN), especially for optimizing traffic signal control strategy, the public transit vehicles will be prioritized to improve their travel efficiency, while the overall delay of road traffic flow will be balanced to ensure the safe and orderly passage of intersections. In order to verify the validity of the model, the SUMO traffic analysis software has been applied to simulate real-time traffic control, and the experimental results show that compared with the traditional timing signal control, the loss time of vehicles is reduced by nearly 40%, and the cumulative loss time per capita is reduced by nearly 43.5%, and a good control effect is achieved. In the case of medium and low densities, it is better than the solid scheduled traffic control scheme. [ABSTRACT FROM AUTHOR]

HELQ plays a key role in DNA damage response and cell‐cycle checkpoint regulation. It has been implicated in ovarian and pituitary tumors and may play a role in germ cell maintenance. This study investigated the role of HELQ in lung cancer. The expression of HELQ in patients with non‐small‐cell lung cancer (NSCLC) was downregulated compared with normal human lungs. Clinical prognostic analysis of Kaplan–Meier plots revealed that patients with NSCLC with low HELQ levels had a reduced overall survival. Further, we found that HELQ depletion enhanced lung cancer cell malignancy. Furthermore, overexpression of HELQ in lung cancer cells reduced cell migration in vitro, while DNA damage repair was inhibited. Both in vitro and in vivo studies have shown that HELQ induces cell death. Mechanistically, we found that cells overexpressing HELQ showed a tendency to induce necrosis. After analyzing the database of HELQ interactors. we found that RIPK3 may interact with it and proved this conclusion by immunoprecipitation. Our findings identified the tumor suppressive role of HELQ in malignant human lung cancer and unraveled a potential therapeutic strategy for cancer treatment through HELQ activation. Moreover, HELQ may also be a predictive biomarker for the clinical predisposition, progression, and prognosis of lung cancer. [ABSTRACT FROM AUTHOR]

Rapid, non-destructive, and precise salmon species identification is a pressing necessity in the food safety domain. This paper proposes an innovative method for salmon identification grounded in lipid characteristics. To monitor the disparities in lipid traits across various salmon species, Raman spectroscopy was employed for swift and non-invasive measurement of fatty acid composition. The findings revealed significant differences in the unsaturation levels and content of certain long-chain fatty acids among salmon varieties. C18:3n3, C16:0, C14:0, C16:1n7, C18:1n9c, and C18:2n6c were identified as the most crucial fatty acids for salmon differentiation. Raman spectroscopy effectively captured variations in fatty acid profiles, accurately predicting the content of C14:0, C16:1n7, and C18:2n6c, with determination coefficients (R2) of 0.96, 0.90, and 0.87, respectively. To predict salmon species, a novel ensemble model, PLSR_SVM_AdaBoost-LinearRegression (PSA-LR), was proposed. The synergy of Raman spectroscopy and PSA-LR facilitated precise identification of different salmon species, with a determination coefficient (R2) of 0.86, Root Mean Square Error of Prediction (RMSEP) of 0.37, and an accuracy of 100%. The results demonstrate that lipid characteristics serve as effective indicators for salmon species identification, and the combination of Raman spectroscopy with an ensemble model enables rapid, non-destructive, and accurate salmon species discrimination. • Salmon species were identified based on lipid characteristics. • Raman could predict the fatty acid content of C16:1n7, C18:1n9c and C18:2n6c. • A PSA-LR model was proposed to identify salmon species with accuracy of 100%. [ABSTRACT FROM AUTHOR]

Leading by the antiviral activities against HSV-2 virus, bioactivity-guided the fraction of crude alkaloids from seeds of Peganum harmala led to the isolation of nine structurally novel indole alkaloids, pegaharolines A − I (1 – 9), and 11 known ones (10 − 20). Compound 3 was an unusual 6/5/5/5 spirotetracyclic indole-derived alkaloids featuring a classic bicyclic indole unit fused with an additional pyrrolizine ring via a spiral atom (C-3). Compound 4 was determined as a novel indole alkaloid, characterized with a rare hexacyclic 6/5/6/5–6/6 ring system, by a single-crystal X-ray diffraction. Compounds 5 and 6 were peculiar indole dimers featuring with the rare carbon skeleton of an octacyclic scaffold. Compounds 1 – 6 were six racemates. Most compounds exhibited different levels of antiviral activities against HSV-2. Especially, the anti-HSV-2 activity of compound 1 (IC 50 = 0.90 ± 0.10 μM) was much better than that of the positive control (acyclovir, IC 50 = 1.12 ± 0.15 μM). In this study, the discovery of anti-HSV-2 components from the seeds of P. harmala , could benefit development and utilization of this plant in antiviral medicinal products. [Display omitted] [ABSTRACT FROM AUTHOR]

• Currently, all CAR-T products on the market target hematological tumors, and most of the CAR genes are assembled in T cells with lentiviral vector. • In our study, we used retroviral vector to assemble CD19 CAR assembly in T cells, which greatly reduced production costs. • The produced anti-CD19 CAR-T has a good clinical efficacy in patients with relapsed/refractory grade 2 follicular lymphom, and there are no other serious side effects except grade 2 CRS. • In addition, pseudo-progression and cytomegalovirus pneumonia occurred at the same time after infusion, and the patient's condition improved after treatment, which has never been seen in previous reports. • Our report may have important implications for reducing the production cost of CAR-T and curing more patients, and the rare complications in our report may help clinical management of CAR-T therapy. CD19-directed chimeric antigen receptor (CAR) T cell therapy has been shown to achieve a considerably durable response in patients with refractory or relapsed B cell non-Hodgkin lymphomas. Most of these CARs were generated by lentivirus. With the exception of Yescarta and Tecartus, few patients with relapsed-/refractory- lymphoma have been treated clinically with a CARs using retroviral vector (RV). Here, we reported a relapsed/refractory grade 2 follicular lymphoma patient with multiple chemotherapy failures, and was treated with a novel CD19 CAR-T cell manufactured from a RV. After tumor burden was reduced with Obinutuzumab and Duvelisib, the patient was infused novel CD19 CAR-T cells at a dose of 3 × 106 cells/ kg. Then he experienced a rapid response and achieved almost complete remission by day 26. Only grade 2 CRS, bilateral submaxillary lymph node enlargement and cytomegalovirus (CMV) infection occurred without neurotoxicity, and the patient's condition improved after a series of symptomatic treatments. In addition, CAR copy number peaked at 532,350 copies/μg on day 15 and continued to expand for 5 months. This may be the first case report of RV preparation of novel CD19 CAR-T cells for direct treatment of recurrent follicular lymphoma. We will observe its long-term efficacy and conduct trials in more patients in the future. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Sophaloseedlines A—G (1—7), seven new matrine‐based alkaloids along with two known analogues, were isolated from the seeds of Sophora alopecuroides. The new structures were determined based on extensive spectroscopic data, electronic circular dichroism calculations, and X‐ray crystallography. Notably, sophaloseedline A (1) represents a novel rearranged 6(5→17)‐abeo‐matrine alkaloid featuring unprecedented highly constructed 7/6/5/6 tetracyclic fused ring skeleton. The hypothetical biosynthetic pathways for sophaloseedlines A—F were proposed based on co‐existing precursors. Additionally, all the isolated alkaloids were screened for their antiviral activities against hepatitis B virus, and new alkaloids 1 and 2 displayed more potent activities than those of matrine (a parent alkaloid of title plant) and positive control (lamivudine). [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Five new sesquiterpenoids (1—5), chloranholides A—E, along with three known compounds (6—8), were isolated from the whole plants of Chloranthus holostegius. Their structures were elucidated using the spectroscopic methods (IR, UV, HR‐ESI‐MS, 1D and 2D NMR), and their absolute configurations were determined by the X‐ray crystallography and ECD calculation. Compounds 1—8 were evaluated for their anti‐inflammatory effects on LPS‐induced RAW 264.7 macrophage cells. Especially, compound 4 exhibited the most significant anti‐inflammatory activity with the secretion levels of TNF‐α and IL‐6 at 15.52% and 5.98%, respectively, better than that of dexamethasone. [ABSTRACT FROM AUTHOR]

Three different alumina/aluminum bi-layer armors having different striking faces, i.e., monolithic alumina, mosaic alumina, and mosaic alumina enhanced by aluminum honeycomb, were fabricated and tested under the impact of the flat projectile. The ballistic performance of each armor type was also investigated using three-dimensional (3D) finite element (FE) simulations. Upon validating the FE simulation results with experimental measurements, the ballistic limit velocity and failure mechanisms for each type of armor, as well as the influence of ceramic tile size, impact position, border effect, and inter tile gap width were quantified. For the enhanced mosaic armor, the metallic honeycomb lattice performed as a cellular skeleton to confine the ceramic tiles and fragments, leading to enhanced ballistic resistance. Besides, the honeycomb enhanced mosaic armor was also found to have much improved multi-hit ballistic resistance in comparison with monolithic and mosaic alumina. The honeycomb preserved the structural integrity of the mosaic armor so that a high level of residual ballistic resistance remained even after impact. With the extended reliability calculation method, single shot ballistic data were used to estimate the performance of the honeycomb enhanced mosaic armor under multiple projectile impacts. [ABSTRACT FROM AUTHOR]

Extra noise is generated when jets are installed beneath solid surface. In this paper, large-eddy simulation (LES) has been used to investigate these jet installation effects. The simulations were performed on two jet configurations: an isolated jet and a jet installed below a horizontal flat plate. The LES is compared with experimental data from measurements using hot wires, unsteady surface pressure sensors, and far-field microphones. Good agreement has been achieved between LES and experimental measurements on flow statistics, space-time correlations, and both near-field and far-field sound spectra. The installed effects are discussed from the perspective of flows and acoustics in the validation process. [ABSTRACT FROM AUTHOR]

Human alkyladenine DNA glycosylase (hAAG) is essential for repairing alkylated and deaminated bases, and it has become a prospective diagnosis biomarker and a therapeutic target for disease treatment. However, most of hAAG assays suffer from complicated reaction scheme, poor specificity, long assay time, and limited sensitivity. Herein, we report a novel single probe-based catalytic quantum dot (QD) Förster resonance energy transfer (FRET) nanosensor for simple and sensitive detection of hAAG activity. In this assay, hAAG induces the generation of 3′ OH terminus via the excision of I base and the cleavage of AP site by APE1, subsequently initiating strand displacement reaction to produce numerous ssDNA signal probes. These probes can self-assemble on the QD surface to induce efficient FRET between QD and Cy5. This assay is very simple with the involvement of only a single probe for the achievement of both specific sensing and efficient signal amplification. Moreover, each signal probe contains multiple Cy5 moieties, and multiple signal probes can assemble on a single QD to greatly enhance the FRET efficiency. This nanosensor exhibits a detection limit of 3.60 × 10−10 U/μL and it is suitable for measuring enzymatic kinetics, screening inhibitor, and quantifying cellular hAAG activity with single-cell sensitivity. A single probe-based catalytic quantum dot FRET nanosensor is developed for sensing human alkyladenine DNA glycosylase at single-cell level. [Display omitted] • We construct a single probe-based catalytic quantum dot FRET nanosensor. • This sensor can sensitively detect human alkyladenine DNA glycosylase. • This nanosensor can quantify cellular hAAG activity at single-cell level. • This nanosensor can measure enzymatic kinetics and screen inhibitor. [ABSTRACT FROM AUTHOR]

Acute myocardial infarction (AMI) is a global health threat, and programmed cell death (PCD) plays a crucial role in its occurrence and development. In this study, integrated bioinformatics tools were used to explore new biomarkers and therapeutic targets in AMI. Thirteen types of PCD-related genes were identified through literature review, KEGG, and GSEA pathways. Gene expression matrices and clinical data from AMI patients and healthy controls were obtained from the GEO database. Statistical analysis in R identified 377 differentially expressed genes in AMI patients. Intersection analysis between the differentially expressed genes and PCD-related genes revealed 24 genes positively correlated with immune cells such as Neutrophils and Monocytes, while negatively correlated with T cells CD4 memory resting and Plasma cells. Unsupervised clustering analysis divided patients into two groups (C1 and C2) based on the expression levels of these 24 genes. GSVA analysis showed that C2 patients were more active in pathways related to maintaining normal cell morphology and promoting phagocytosis, suggesting a lower programmed cell death rate and a higher tendency to maintain cell survival. Two hub genes, TNFAIP3 and TP53INP2, were identified through LASSO regression analysis and SVM-RFE, and were validated using an external dataset and RT-qPCR、Western blot and ELISA analysis. These hub genes showed significantly higher expression and protein secretion levels in AMI patients compared to healthy individuals. Overall, regulating and controlling PCD, particularly through the identified hub genes, TNFAIP3 and TP53INP2, may provide new therapeutic strategies for improving the prognosis of AMI patients and preventing heart failure. • In this study, we discovered genes associated with 13 different forms of programmed cell death. • This study identified TNFAIP3 and TP53INP2 as critical HUB genes in the progression of AMI. • This study validated the high expression of TNFAIP3 and TP53INP2 in AMI patients. [ABSTRACT FROM AUTHOR]

Aiming at the vulnerability propagation of all-optical networks, combining with the characteristics of the all-optical network, a formal modeling and analysis method for vulnerability propagation based on Bio-PEPA is proposed in this paper. First of all, the main characteristics that influence the vulnerability propagation are analyzed. Then, the optical fibers, optical amplifiers and optical switches are abstract into three different clusters, and the propagation behavior of vulnerability in intra-cluster and inter-cluster are described accurately. In addition, Ordinary Differential Equations is used for model parsing. Finally, through testing the main factors of vulnerability propagation, such as the number of nodes with potential vulnerability, system detection and repair rate, it is shown that the model constructed in this paper can reflect the vulnerability propagation trend of all-optical networks reasonably. At the same time, the proposed method can avoid the state space explosion problem of traditional modeling methods. [ABSTRACT FROM AUTHOR]

Using large-eddy simulation-Reynolds-averaged Navier-Stokes (LES-RANS), this paper studies a round coaxial nozzle with an ultra-high bypass ratio of 15, with and without a wing-flap geometry. Depending on engine placement, the nozzle can become extremely close to the wing-flap geometry, introducing strong installation effects. Two different flap deflections of 8 and 14 deg are contrasted with an isolated round nozzle. A flight stream is applied and an Ffowcs Williams-Hawkings (FWH) surface placement procedure for installed jets is proposed. Impressive agreement with available experimental data is economically achieved for far-field overall sound pressure level and spectra as well as near-field spectra. The LES provides a wider range of polar and azimuthal angles at 1 deg increments, providing one of the most detailed acoustics data sets to date. The installed cases generate up to 20 dB more noise at mid-low frequencies due to large flap trailing edge sources. Additional sources are introduced by the interaction of the flight stream with the lifting surfaces. Second-order space-time correlations reveal length and time scales in the flow. Fourth-order space-time correlations indicate increasing magnitudes of the dominant noise source components with increasing flap angle. The three-dimensional unsteady data set produced should lead to improved acoustics models. [ABSTRACT FROM AUTHOR]

Abstract Serrated jet nozzles are considered to be an efficient and practical passive control approach for jet noise. However, some fundamental mechanisms of serration effects on jet noise are not fully understood, especially in terms of the sound source. In this paper, a high-fidelity simulation framework using large-eddy simulation (LES) is demonstrated to predict near-field turbulence and far-field acoustics from an ultra-high-bypass-ratio engine with round and serrated nozzles. Far-field sound is predicted using Ffowcs Willams–Hawkings (FWH) integration. The results show that the serrated nozzle increases mixing near the nozzle and hence the turbulence decay rate, reducing the turbulence level downstream. The serrations shift the energy from the low frequencies to the high frequencies and decrease overall sound pressure levels by about 3 dB over the low-frequency range. Sound sources are analysed based on fourth-order space–time correlations. There are six major source components (R 1111 , R 2222 , R 3333 , R 1313 , R 1212 , and R 2323) inside the jet shear layers. The serrations are able to reduce the amplitude of these source terms, causing them to decay rapidly to a level below the round nozzle jet within 2 D downstream of the nozzle. [ABSTRACT FROM AUTHOR]

The target tracking issue has always been the hotspot in wireless sensor network, and with the emergence of new application in multimedia and real-time transmission, new requirements are proposed for transmission performance of target tracking routing; therefore, a software-defined network-based hierarchical adaptive routing algorithm of wireless sensor network is proposed in this article. The algorithm takes into account both network energy and throughput, uses Hopfield neural network algorithm to calculate the optimal path among adjacent clusters as a local routing (LR), and builds the Multi-choice Knapsack Problem model based on local paths to realize end-to-end global routing, in order to realize the routing of tracking target information under multi-objective conditions. The test bed includes physical and simulation tests. Experimental results show that the proposed algorithm is superior to low energy adaptive clustering hierarchy (LEACH) and Sequential Assignment Routing under different test scenarios. [ABSTRACT FROM AUTHOR]

Background: Osteoarthritis (OA) is a joint disease in which cartilage degradation is the central pathological change. In this study, we investigated the anti-osteoarthritic effects of licochalcone A (Lico A) in rat chondrocytes. Methods: Polymerase chain reaction and Western blotting were performed to evaluate the expression of a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-5, ADAMTS-4, collagen II, matrix metalloproteinase (MMP)-13 and MMP-1 at both the gene and protein levels, respectively. In addition, the wnt/β-catenin and nuclear factor kappa B (NF-κB) signaling pathways were also analyzed by Western blotting. Results: Lico A downregulated ADAMTS-5, ADAMTS-4,MMP-13 and MMP- 1 expression, and diminished the IL-1β-induced inhibition of collagen II. In addition, the activation of β-catenin and phosphorylation of p65 and IKKa/β were suppressed by Lico A. Conclusions: Our results suggest that Lico A inhibits MMPs and ADAMTS partly via the NF-κB and wnt/β-catenin signaling pathways in rat chondrocytes. Thus, Lico A may have therapeutic effects in OA. [ABSTRACT FROM AUTHOR]

Olfaction is primarily mediated by highly specified olfactory receptors (ORs). Here, we cloned and identified an olfactory receptor, named SlituOR1 (Genbank no. JN835269), from Spodoptera litura and found evidence that it is a candidate pheromone receptor. It exhibited male-biased expression in the antennae, where it was localized at the base of sensilla trichoidea, the antennal sensilla mainly responsive to pheromones in moths. Conserved orthologues of this receptor, found among known pheromone receptors within the Lepidoptera, and SlituOR1 were placed among a clade of candidate pheromone receptors in a phylogeny tree of insect OR gene sequences. SlituOR1 showed differential expression in S. litura populations attracted to traps baited with different ratios of the two sex pheromone components (9 Z,11 E)-tetradecadienyl acetate ( Z9 E11-14:OAc) and (9 Z,12 E)-tetradecadienyl acetate ( Z9 E12-14:OAc). Knocking down of SlituOR1 by RNA interference reduced the electroantennogram (EAG) response to Z9 E11-14:OAc, and this result is consistent with the field trapping experiment. We infer that variation in transcription levels of olfactory receptors may modulate sex pheromone perception in male moths and could provide some of the flexibility required to maintain the functionality of communication with females when a population is adapting to a new niche and reproductive isolation becomes an advantage. [ABSTRACT FROM AUTHOR]

Seven sesquiterpene lactones, 8- O -methacryloylelephanpane, 2,4-bis- O -methyl-8- O -methacryloylelephanpane, 4- O -ethyl-8- O -methacryloylelephanpane, 8- O -methacryloylisoelephanpane, 2- O -demethyltomenphantopin C, molephantin A, molephantin B, along with ten known ones, were isolated from Elephantopus mollis (Asteraceae). Their structures were elucidated by extensive analysis of spectroscopic data (IR, UV, HRESIMS, 1D and 2D NMR). The isolates were evaluated for their anti-inflammatory activities on LPS-stimulated RAW 264.7 cells, and all tested compounds exhibited potent anti-inflammatory effects with IC 50 values of 0.57 ± 0.17 to 14.34 ± 1.61 μ M, except that compound tomenphantopin C exhibited moderate anti-inflammatory activity with IC 50 values of 59.97 ± 1.53 μ M. [ABSTRACT FROM AUTHOR]

• Nitrogen addition accelerated decomposition of low-quality monospecific litter. • Nitrogen addition shifted synergistic to additive effects during mixed litter decomposition. • Litter quality mediated N addition effects on monospecific litter decomposition. • Nitrogen addition altered mixed litter decomposition by reducing synergistic effects. Litter decomposition is a key determinant of soil organic matter accumulation in boreal peatlands. Climate warming and atmospheric nitrogen (N) deposition have recently increased N availability in boreal peatlands. However, how increased N availability alters decomposition dynamics of plant litter is uncertain in these ecosystems, especially for litter mixtures. Here, we collected fresh litter of four common species (Betula fruticosa , Ledum palustre , Eriophorum vaginatum , and Sphagnum palustre) in a poor fen of northeast China, and established an N addition (6 g N m−2 year−1) experiment to assess the effect of increased N availability on monospecific and mixed litter decomposition in the hummocks and hollows after one and three years of decomposition. In both hummocks and hollows, N addition increased mass loss of four monospecific litter after one year of decomposition but only accelerated litter decomposition of E. vaginatum and S. palustre with low litter quality after three years of decomposition. Moreover, N addition effects on monospecific litter decomposition were negatively related to monospecific litter decomposition in the absence of N addition. Irrespective of decomposition position, additive effects were more frequent than synergistic effects during decomposition of litter mixtures. In addition, N addition generally changed synergistic effects to additive effects after one and three years of decomposition, and such changing trends were stronger in hummocks than in hollows. These observations suggest that litter quality mediates N addition effects on monospecific litter decomposition, and highlight that increased N availability will alter mixed litter decomposition by reducing synergistic effects in boreal peatlands. [ABSTRACT FROM AUTHOR]

Human single-stranded selective monofunctional uracil glycosylase (hSMUG1) is an important uracil-DNA glycosylase (UDG) subfamily responsible for repair of uracil and oxidized pyrimidine derivatives as well as maintenance of genomic integrity. The abnormal hSMUG1 level is closely associated with various human diseases and cancers. Herein, we demonstrate for the first time the programmable strand displacement-driven assembly of single quantum-dot (QD) nanosensor for accurately monitoring hSMUG1 at single-cell level. We used an oxidation marker 5-hydroxymethyluracil (5hmU) as a novel specific catalysis site for hSMUG1. The presence of hSMUG1 catalyzes 5hmU excision to activate exponential strand-displacement cascades for producing abundant primer probes. Subsequently, primer probes induce the self-assembly of 605QD-dsDNA-Cy5 nanostructures and fluorescence resonance energy transfer (FRET) between 605QD and Cy5. The FRET signal can be quantified via single-molecule imaging. This single QD nanosensor exhibits a detection limit of 7.08 × 10−11 U/μL over a wide dynamic range of 8 orders of magnitude. Importantly, it can measure enzymatic kinetics, screen potential inhibitors, discriminate hSMUG1 expression between cancer cells and normal cells, and quantify hSMUG1 activity in various cancer cells at single-cell level, promising a new avenue for hSMUG1-related biomedical studies and clinical diagnostics. • Single quantum dot nanosensor is assembled by programmable strand displacement. • This nanosensor can detect hSMUG1 in various cells at single-cell level. • This nanosensor exhibits good specificity and high sensitivity. • This nanosensor can measure kinetic parameters and screen potential inhibitors. [ABSTRACT FROM AUTHOR]

As of 28 February 2022, China has vaccinated 87.64% of the whole population with at least two doses of SARS-CoV-2 vaccines, with 40.32% completing the third-dose boosting vaccination. The community-based dynamic zeroing policy has played a pivotal role in minimizing the number of laboratory-confirmed cases and deaths in mainland China. The transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the culprit pathogen of coronavirus disease 2019 (COVID-19), has resulted in more than 0.43 billion cases and 6 million deaths globally. [Extracted from the article]

Large-eddy simulations are performed for hot and cold jets with and without a flight stream. The acoustic and flight stream Mach numbers are 0.875 and 0.3, respectively. The temperature ratios for the hot and cold jets are 2.7 and 1.0, respectively. The mean flow field results are in good agreement with the measurements. The Ffowcs Williams-Hawkings equation is used to predict far-field noise. Several axisymmetric Ffowcs Williams-Hawkings surfaces at increasing radial distances are used. They show that the surfaces closer to the jet can be affected by the hydrodynamic pressure. It is important to close the Ffowcs Williams-Hawkings surfaces at the ends to account for all the acoustic signals emanating from the jet. In this work, 11 end discs are used at the downstream end of the Ffowcs Williams-Hawkings surface. It is found that the simple averaging processes to cancel hydrodynamic sound at the end discs are insufficient for slowly decaying jets. In such cases, a partially closed disc can be a better choice. To remove hydrodynamic signals, a filtering scheme for the end discs is suggested. For slowly decaying jets, this gives better results. [ABSTRACT FROM AUTHOR]

Nine previously undescribed diterpenoids, euphorfiatnoids A−I, together with seven known diterpenoids, were isolated from the roots of wild Euphorbia fischeriana. Their structures were elucidated by the interpretation of HRESIMS, UV, and NMR data. Their configurations were determined by electronic circular dichroism (ECD) spectroscopy analysis and the structure of euphorfiatnoid A was confirmed by X-ray crystallography. To further understand the antitumor effects of E. fischeriana, we tested the cytotoxicity of these compounds against H460, HepG2, and MCF-7 cell lines in vitro using MTT assays. Euphorfiatnoid B exhibited the most promising inhibitory effect against H460 cells with an IC 50 value of 9.97 μM. Euphorfiatnoid A and C also exhibited moderate cytotoxicity against HepG2 cells with IC 50 values of 11.64 and 13.10 μM, respectively. [Display omitted] • Sixteen diterpenoids were isolated from the roots of Euphorbia fischeriana. • Their structures were elucidated by NMR, MS, ECD, and X-ray crystallography. • Euphorfiatnoid G (7) was an undescribed 2,3-seco- ent-atisanes diterpenoid. • Theα, β-unsaturated γ ketone group may enhance the cytotoxicity of diterpenoids. [ABSTRACT FROM AUTHOR]

We developed and optimized a high-throughput project workflow to generate renewable recombinant antibodies to human proteins involved in epigenetic signalling. Three different strategies to produce phage display compatible protein antigens in bacterial systems were compared, and we found that in vivo biotinylation through the use of an Avi tag was the most productive method. Phage display selections were performed on 265 in vivo biotinylated antigen domains. High-affinity Fabs (<20nM) were obtained for 196. We constructed and optimized a new expression vector to produce in vivo biotinylated Fabs in E. coli. This increased average yields up to 10-fold, with an average yield of 4 mg/L. For 118 antigens, we identified Fabs that could immunoprecipitate their full-length endogenous targets from mammalian cell lysates. One Fab for each antigen was converted to a recombinant IgG and produced in mammalian cells, with an average yield of 15 mg/L. In summary, we have optimized each step of the pipeline to produce recombinant antibodies, significantly increasing both efficiency and yield, and also showed that these Fabs and IgGs can be generally useful for chromatin immunoprecipitation (ChIP) protocols. [ABSTRACT FROM AUTHOR]

A facile, atom-economical, and efficient Cu(OAc)2-catalyzed oxidative esterification of substituted p-cresols was developed with ambient air as the terminal oxidant. This ligand- and additive-free esterification protocol allows an environmentally benign and reagent-economical access to benzyl esters. [ABSTRACT FROM AUTHOR]

Purpose: Hypoxia is an inevitable consequence of many respiratory diseases resulting from inadequate alveolar ventilation. As pulmonary dysfunction is recently recognized as one of the many clinical features associated with diabetes, this study aims to investigate the effect of streptozotocin (STZ)-induced diabetes on hypoxia-induced lung injury. Materials and Methods: Mice were randomly allocated to four groups (Control, Hypoxia, Diabetes, Diabetes+Hypoxia). Control and type I diabetic (100 mg/kg STZ-treated) mice were followed for 4 weeks and finally exposed to normoxia or hypoxia (8% O2). Twelve hours later, lung tissues were collected for histopathologic examination, and determination of interleukin (IL)-1β, IL-6, myeloperoxidase (MPO), malondialdehyde (MDA), total antioxidant capacity (T-AOC), superoxide dismutase (SOD) activity, and Toll-like receptor (TLR)4 expression. Results: STZ-induced diabetes aggravated histopathological changes in the lung exposed to acute hypoxia. Hypoxia increased lung MDA level but decreased T-AOC and SOD activity. STZ-induced diabetic mice presented significant increases in MDA level and SOD activity in the lung. Moreover, no difference was found in the levels of both oxidant index (MDA) and anti-oxidant indexes (T-AOC and SOD) between 'Hypoxia' group and 'Hypoxia plus Diabetes' group. On the other hand, STZ-induced diabetic mice presented significant increases in pulmonary neutrophil infiltration, pro-inflammatory cytokines (IL-1β and IL-6) production, as well as TLR4 expression. Although acute hypoxia alone had no significant effect on pulmonary inflammatory markers, it profoundly increased STZ-diabetes-induced neutrophil infiltration, pro-inflammatory cytokine production, and TLR4 expression in lung tissues. Conclusions: STZ-induced diabetes may aggravate acute hypoxia-induced lung injury through enhancing pulmonary inflammatory responses. [ABSTRACT FROM AUTHOR]

Summary Background Ceftriaxone with or without a macrolide antibiotic is a recommended treatment for patients with community-acquired pneumonia requiring hospital admission and intravenous antibiotic treatment. We aimed to assess the efficacy and safety of ceftaroline fosamil compared with ceftriaxone in the treatment of Asian patients admitted to hospital with community-acquired pneumonia. Methods In this international, randomised, controlled, double-blind, phase 3, non-inferiority with nested superiority trial, adult Asian patients with Pneumonia Outcomes Research Team (PORT) risk class III–IV acute community-acquired pneumonia were randomly assigned (1:1) to receive intravenous ceftaroline fosamil (600 mg every 12 h) or ceftriaxone (2 g every 24 h) for 5–7 days. Patients were randomly assigned via centralised telephone and web-based system; patients and treating clinicians were masked to treatment allocation. Investigators who did study assessments remained masked to treatment allocation until completion of the study. The primary endpoint was clinical cure at the test-of-cure visit (8–15 days after last dose of study drug) in the clinically evaluable population. Non-inferiority of ceftaroline fosamil was defined as a lower limit of the two-sided 95% CI for the difference in the proportion of patients clinically cured of −10% or higher; if non-inferiority was achieved, superiority was to be concluded if the lower limit of the 95% CI was greater than 0%. This trial is registered with ClinicalTrials.gov , number NCT01371838 . Findings Between Dec 13, 2011, and April 26, 2013, 847 patients were enrolled at 64 centres in China, India, South Korea, Taiwan, and Vietnam, of whom 771 were randomly assigned and 764 received study treatment. In the clinically evaluable population (n=498) 217 (84%) of 258 patients in the ceftaroline fosamil group and 178 (74%) of 240 patients in the ceftriaxone group were clinically cured at the test-of-cure visit (difference 9·9%, 95% CI 2·8–17·1). The superiority of ceftaroline fosamil was consistent across all preplanned patient subgroup analyses (split by age 65 years, age 75 years, sex, PORT risk class, and previous antibiotic use) apart from patients younger than 65 years. The frequency of adverse events was similar between treatment groups and the safety results for ceftaroline fosamil were consistent with the cephalosporin class and previous clinical trial data. Interpretation Ceftaroline fosamil 600 mg given every 12 h was superior to ceftriaxone 2 g given every 24 h for the treatment of Asian patients with PORT III–IV community-acquired pneumonia. These data suggest that ceftaroline fosamil should be regarded as an alternative to ceftriaxone in empirical treatment regimens for this patient population. Funding AstraZeneca. [ABSTRACT FROM AUTHOR]

The discussion of the use event-related potentials (ERPs) to analysis the mechanisms of double object structure in the brain. It examines brain's legality of the collocation for double object and bivalent-verb object. The analysis shows given double object, taken double object and atypical double object made up by bivalent-verb object have their own processing mechanism. The result shows given double object needs less energy in psychological requirements. Taken double object and atypical object show no significant differences in their processing mechanism. However, the grammatical usage of the structures processing of given double object and the other two types of double object did show differences. This may demonstrate processing mechanism in early period of Chinese was not just simple pure syntax analysis but also semantic processing analysis. It shows semantic played important role in the development of double object structures in Chinese. [ABSTRACT FROM AUTHOR]

Two new Ru(II) complexes, [Ru(bpy)2(FAMP)](ClO4)21 and 2, are synthesized and characterized by elemental analysis, electrospray mass spectrometry, and 1H nuclear magnetic resonance. The in vitro cytotoxicities and apoptosis-inducing properties of these complexes are extensively studied. Complexes 1 and 2 exhibit potent antiproliferative activities against a panel of human cancer cell lines. The cell cycle analysis shows that complexes 1 and 2 exhibit effective cell growth inhibition by triggering G0/G1 phase arrest and inducing apoptosis by mitochondrial dysfunction. The in vitro DNA binding properties of the two complexes are investigated by different spectrophotometric methods and viscosity measurements. [ABSTRACT FROM AUTHOR]

A highly conserved and broadly expressed receptor protein Orco (olfactory coreceptor) is crucial for insect olfaction, and an orthologue of Orco has been identified in several insect species. Here we report the identification and characterization of Orco from Spodoptera litura. The protein displays high primary amino acid sequence conservation with other previously identified Orco orthologues. Bioinformatic analysis revealed that it has common features with other members of the Orco subfamily: seven-transmembrane domains with intracellular N-terminus and extracellular C-terminus. The transcript was detected in abundance in the chemosensory organs of the antennae of both male and female adults by real-time polymerase chain reaction analysis, and was localized at the bases of all categories of olfactory sensilla through in situ hybridization. [ABSTRACT FROM AUTHOR]

Two new ruthenium(II) polypyridyl complexes [Ru(dmb)2(HECIP)](ClO4)2 (1) (HECIP = N-ethyl-4-[(1,10)-phenanthroline(5,6-f)imidazol-2-yl]carbazole, dmb = 4,4’-dimethyl-2,2’-bipyridine) and [Ru(dmp)2(HECIP)](ClO4)2 (2) (dmp = 2,9-dimethyl-1,10-phenanthroline) have been synthesized and characterized. The DNA-binding behaviors of the two complexes were investigated by absorption spectra, viscosity measurements, and photoactivated cleavage. The DNA-binding constants for complexes 1 and 2 were determined to be 8.03 (± 0.12) × 104 M−1 (s = 1.62) and 2.97 (± 0.15) × 104 M−1 (s = 1.82), respectively. The results suggest that these complexes interact with DNA through intercalative mode. The photocleavage of pBR322 DNA by Ru(II) complexes was investigated. The cytotoxicity of complexes 1 and 2 has been evaluated by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide)] method. Complex 1 shows higher anticancer potency than 2 against the four tumor cell lines. Apoptosis and cellular uptake were investigated. The antioxidant activities of the ligand and these complexes were also performed. [ABSTRACT FROM AUTHOR]

Two new ruthenium(II) polypyridyl complexes, [Ru(bpy)2(DMDPPZ)](ClO4)2 (1) (bpy = 2,2′-bipyridine, DMDPPZ = 3,6-dimethyldipyrido[3,2-a:2′,3′-c]phenazine) and [Ru(dmb)2(DMDPPZ)](ClO4)2 (2) (dmb = 4,4′-dimethyl-2,2′-bipyridine), have been synthesized and their DNA-binding, photoinduced DNA cleavage, and cell cytotoxicity are studied. The complexes show good binding to calf thymus DNA in the order: 1 > 2. Both complexes exhibit efficient DNA cleavage upon irradiation via a mechanistic pathway involving formation of singlet oxygen as the reactive species. The cytotoxic activity of 1 and 2 was tested by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) method. These complexes effectively inhibit the proliferation of tumor cells. The antioxidant activity against hydroxyl radical (•OH) was also explored. [ABSTRACT FROM AUTHOR]

Abstract: Loss-of-function mutations in DJ−1 are associated with early-onset of Parkinson''s disease. Although DJ−1 is ubiquitously expressed, the functional pathways affected by it remain unresolved. Here we demonstrate an involvement of DJ−1 in the regulation of Ca2+ homeostasis in mouse skeletal muscle. Using enzymatically dissociated flexor digitorum brevis muscle fibers from wild-type (wt) and DJ−1 null mice, we examined the effects of DJ−1 protein on resting, cytoplasmic [Ca2+] ([Ca2+] i ) and depolarization-evoked Ca2+ release in the mouse skeletal muscle. The loss of DJ−1 resulted in a more than two-fold increase in resting [Ca2+] i . While there was no alteration in the resting membrane potential, there was a significant decrease in depolarization-evoked Ca2+ release from the sarcoplasmic reticulum in the DJ−1 null muscle cells. Consistent with the role of DJ−1 in oxidative stress regulation and mitochondrial functional maintenance, treatments of DJ−1 null muscle cells with resveratrol, a mitochondrial activator, or glutathione, a potent antioxidant, reversed the effects of the loss of DJ−1 on Ca2+ homeostasis. These results provide evidence of DJ−1''s association with Ca2+ regulatory pathways in mouse skeletal muscle, and suggest the potential benefit of resveratrol to functionally compensate for the loss of DJ−1. [Copyright &y& Elsevier]

Abstract: Recently, evidence of linkage of schizophrenia to chromosome 13q22-q34 has been demonstrated in multiple studies. Based on structure and function, EFNB2 may be considered as a compelling candidate gene for schizophrenia on chromosome 13q33. We genotyped three single-nucleotide polymorphisms (SNPs: rs9520087, rs11069646, and rs8000078) in this region in 846 Han Chinese subjects (477 cases and 369 controls). Significant association between an allele of marker rs9520087 and schizophrenia was found. Furthermore, since no LD was observed in the three SNPs linkage disequilibrium estimation, all three SNPs were used in multiple SNPs haplotype analysis, and a strongly significant difference was found for the common haplotype TTC. Overall our findings indicate that EFNB2 gene may be a candidate susceptibility gene for schizophrenia in the Han Chinese population, and also provide further support for the potential importance of the NMDA receptor pathway in the etiology of schizophrenia. [Copyright &y& Elsevier]

The COVID-19 epidemic is raging around the world. Neutralizing antibodies are powerful tools for the prevention and treatment of SARS-CoV-2 infection. Antibody CR3022, a SARS-CoV neutralizing antibody, was found to cross-react with SARS-CoV-2, but its affinity was lower than that of its binding with SARS-CoV, which greatly limited the further development of CR3022 against SARS-CoV-2. Therefore, it is necessary to improve its affinity to SARS-CoV-2 in vitro. In this study, the structure-based molecular simulations were utilized to virtually mutate the possible key residues in the complementarity-determining regions (CDRs) of the CR3022 antibody. According to the criteria of mutation energy, the mutation sites that have the potential to impact the antibody affinity were then selected. Then optimized CR3022 mutants with the enhanced affinity were further identified and verified by enzyme-linked immunosorbent assay (ELISA), surface plasma resonance (SPR) and autoimmune reactivity experiments. Finally, molecular dynamics (MD) simulation and binding free energy calculation (MM/PBSA) were performed on the wild-type CR3022 and its two double-site mutants to understand in more detail the contribution of these sites to the higher affinity. It was found that the binding affinity of the CR3022 antibody could be significantly enhanced more than ten times after the introduction of the S103F/Y mutation in HCDR–3 and the S33R mutation in LCDR–1. The additional hydrogen-bonding, hydrophobic interactions, as well as salt-bridges formed between the modified double-site mutated antibody and SARS-CoV-2 RBD were identified. The computational and experimental results clearly demonstrated that the affinity of the modified antibody has been greatly enhanced. This study indicates that CR3022 as a neutralizing antibody recognizing the conserved region of RBD against SARS-CoV with cross-reactivity with SARS-CoV-2, a different member in a large family of coronaviruses, could be improved by the computational and experimental approaches which provided insights for developing antibody drugs against SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Keywords: coronavirus; COVID-19; laboratory testing; prevention; therapy; transmission EN coronavirus COVID-19 laboratory testing prevention therapy transmission 657 658 2 05/28/20 20200601 NES 200601 The outbreak of coronavirus disease 2019 (Covid-19) has been rapidly spreading, causing a pandemic globally. We must ensure opportunities to develop targeted therapies to Covid-19 and other coronavirus diseases do not cease when the current outbreak is over. Coronavirus, COVID-19, laboratory testing, prevention, therapy, transmission. [Extracted from the article]

Abstract: Wnt signaling is intrinsically involved in diverse cellular activities during cell differentiation, early embryonic development and organogenesis. Although much is known regarding the effects of Wnt signaling in the developing skeletal system, its role during regeneration remains unclear. Herein, we show transcriptional activation of specific members and target genes of the Wnt signaling pathway. Specifically, all of the Wnt signaling members and target genes analyzed were found to be upregulated during the early stages of fracture repair, with the exception of LEF1 whose expression was downregulated. In addition, spatial expression analysis of Dishevelled (Dvl) and β-catenin in the fracture callus revealed an identical pattern of expression with both proteins localizing in osteoprogenitor cells of the periosteum, osteoblasts and proliferating/pre-hypertrophic chondrocytes. Further, in vitro knockdown of all three Dvl isoforms in chondrocytes using small interfering RNAs (siRNA) leads to partial inhibition of cell proliferation and differentiation, decreased expression of chondrogenic markers (ColII, ColX, Sox9) and suppressed nuclear accumulation of unphosphorylated β-catenin. Taken together, these data verify our previous finding that the Wnt signaling pathway is activated during bone regeneration, by characterizing the temporal and spatial expression of a broad spectrum of Wnt-signaling molecules. Our data also suggest that all three Dvl isoforms, acting through the Wnt canonical pathway, are critical regulatory molecules for chondrocyte proliferation and differentiation. [Copyright &y& Elsevier]

Presents a sequence analysis of a 282–kilobase region surrounding the citrus tristeza virus (CTV) resistance gene locus in Poncirus trifoliata L. Raf. Components of the sequence analysis; Investigation of synteny between Arabidopsis and P. trifoliata; Analysis of candidate genes for CTV.

The citrus tristeza virus resistance gene (Ctv) is a single dominant gene in Poncirus trifoliata, a sexually compatible relative of citrus. To clone this gene, a bacterial artificial chromosome (BAC) library has been constructed from an individual plant that was homozygous for Ctv. This library contains 45 696 clones with an average insert size of 80 kb, corresponding to 9.6 genome equivalents. Screening of the BAC library with five chloroplast DNA probes indicated that 0.58% of the BAC clones contained chloroplast-derived inserts. The chromosome walk across the Ctv locus was initiated using three closely linked genetic markers: C19, AD8, and Z16. The walk has been completed and a contig of ca. 1.2 Mb was constructed. Based on new data, the genetic map in the Ctv region was revised, with Ctv being located between AD8-Z16 and C19 at distances of 1.2 and 0.6 cM, respectively. Utilizing DNA fragments isolated from the contig as RFLP markers, the Ctv locus was further mapped to a region of ca. 300 kb. This contig contains several putative disease-resistance genes similar to the rice Xa21 gene, the tomato Cf-2 gene, and the Arabidopsis thalianaRPS2 gene. This library will therefore allow cloning of Ctv and other putative disease-resistance genes.Key words: Poncirus, citrus tristeza virus, chromosome walk, resistance gene.Le gène Ctv conférant la résistance au tristeza est un gène unique et dominant chez le Poncirus trifoliata, une espèce apparentée et sexuellement compatible avec les agrumes. Afin de cloner ce gène, une banque de clones BAC (chromosomes bactériens artificiels) a été produite à partir d'une plante homozygote pour Ctv. Cette banque comprend 45 696 clones dont la taille moyenne est de 80 kb ce qui confère une redondance de 9,6 équivalents génomiques. Le criblage de la banque avec cinq sondes d'ADN chloroplastique a indiqué que 0,58 % des clones contenaient des inserts d'origine chloroplastique. Une marche chromosomique jusqu'au locus Ctv a été initiée à partir de trois marqueurs génétiques fortement liés : C19, AD8 et Z16. La marche a été complétée et a produit un contig d'environ 1,2 Mb. En fonction de données nouvelles, la carte génétique de la région où se trouve Ctv a été révisée, ce locus étant maintenant situé entre AD8-Z16 et C19, à des distances de 1,2 et 0,6 cM respectivement. En utilisant des fragments d'ADN comme sondes RFLP, le locus Ctv a pu être assigné à une région faisant environ 300 kb. Ce contig contient plusieurs gènes de résistance potentiels présentant de l'homologie aux gènes Xa21 du riz, Cf-2 de la tomate et RPS2 d'Arabidopsis thaliana. Cette banque permettra ainsi de cloner Ctv de même que d'autres gènes de résistance putatifs.Mots clés : Poncirus, tristeza, marche chromosomique, gène de résistance.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

ABSTRACT Photoperiod/thermo‐sensitive genic male sterility (P/TGMS) is critical for rice two‐line hybrid system. Previous studies showed that slow development of pollen is a general mechanism for sterility‐to‐fertility conversion of TGMS in Arabidopsis. However, whether this mechanism still exists in rice is unknown. Here, we identified a novel rice TGMS line, ostms16, which exhibits abnormal pollen exine under high temperature and fertility restoration under low temperature. In mutant, a single base mutation of OsTMS16, a fatty acyl‐CoA reductase (FAR), reduced its enzyme activity, leading to defective pollen wall. Under high temperature, the mOsTMS16M549I couldn't provide sufficient protection for the microspores. Under low temperature, the enzyme activity of mOsTMS16M549I is closer to that of OsTMS16, so that the imperfect exine could still protect microspore development. These results indicated whether the residual enzyme activity in mutant could meet the requirement in different temperature is a determinant factor for fertility conversion of P/TGMS lines. Additionally, we previously found that res2, the mutant of a polygalacturonase for tetrad pectin wall degradation, restored multiple TGMS lines in Arabidopsis. In this study, we proved that the osres2 in rice restored the fertility of ostms16, indicating the slow development is also suitable for the fertility restoration in rice. [ABSTRACT FROM AUTHOR]

Benzocyclobutene-modified silsesquioxane (BCB-POSS) and divinyl tetramethyl disiloxane-bisbenzocyclobutene (DVS-BCB) prepolymer were introduced into the containing benzocyclobutene (BCB) unit matrix resin P(4-MB-co-1-MP) polymerized from 1-methyl-1-(4-benzocyclobutenyl) silacyclobutane (4-MSCBBCB) and 1-methyl-1-phenylsilacyclobutane (1-MPSCB), respectively. The low dielectric constant (low-k) siloxane/carbosilane hybrid benzocyclobutene resin composites, P(4-MB-co-1-MP)/BCB-POSS and P(4-MB-co-1-MP)/DVS-BCB, were prepared. The curing processes of the composites were assessed via Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The effects on dielectric properties and heat resistance of those composites with different proportion of BCB-POSS and DVS-BCB were investigated using an impedance analyzer and thermogravimetric analyzer (TGA), respectively. The thermal curing of composites could be carried out by ring-opening polymerization (ROP) of the BCB four-member rings of BCB-POSS or DVS-BCB and those of P(4-MB-co-1-MP). With increasing the proportion of BCB-POSS to 30%, the 5% weight loss temperature (T5%) of P(4-MB-co-1-MP)/BCB-POSS composites was raised visibly, whereas the dielectric constant (k) was decreased owing to the introduction of nanopores into POSS. For P(4-MB-co-1-MP)/DVS-BCB composites, the T5% and k were slightly raised with increasing the proportion of DVS-BCB. The above results indicated that the BCB-POSS showed advantages over conventional fillers to simultaneously improve thermostability and decrease k. [ABSTRACT FROM AUTHOR]

The ballistic performance of a bi-layer armor encapsulated with ultra-high molecular weight polyethylene (UHMWPE) composite laminate was investigated using a combined experimental and numerical approach. Three series of test specimens were examined: (A) bare and encapsulated aluminum (Al) plates, (B) bare and encapsulated bi-layer mosaic armors, and (C) bi-layer mosaic armors having identical areal density but different encapsulation thicknesses. The ballistic behaviors and failure mechanisms of UHMWPE encapsulated Al plates and bi-layer mosaic armors under different projectile impact velocities were analyzed systematically. Attributed to the integration effect of encapsulation, the encapsulated specimens could effectively disperse localized projectile impacting to the entire structure. The results indicated that the UHMWPE encapsulation could enhance significantly the ballistic resistance of traditional ceramic/metal bi-layer armors, due mainly to serious pulling and stretching deformations of the lateral and rear UHMWPE laminates in resisting the projectile impact. However, thicker encapsulation would not necessarily lead to better ballistic performance for specimens with equal areal density. Further, the thickness (or mass) ratio of the armor substructures needed to be tailored synthetically to achieve optimal ballistic performance. [ABSTRACT FROM AUTHOR]

Eight new stilbene dimer xylosides (1 – 8) and one new flavanol (9), along with seven known ones (10 – 16) were isolated from the roots of Lysidice rhodostegia. Their structures were elucidated by extensive analysis of spectroscopic data (IR, UV, HR-ESI-MS, 1D and 2D NMR), ECD calculations and acid hydrolysis. Compounds 1 – 16 were evaluated for their antioxidant activities using DPPH radical-scavenging assay. Especially, compounds 9 and 10 exhibited stronger antioxidant effects than the positive control (vitamin E), with IC 50 values of 9.57 ± 1.30 and 13.60 ± 1.47 μM, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

How to quickly and nondestructively estimate the freshness of salmon meat is necessary and urgent in the food safety market. Raman spectroscopy has become an appealing tool of freshness prediction, but its adaptability and robustness under different temperature conditions need to be further evaluated. In this paper, salmon meat samples stored at −18 °C, 4 °C and 20 °C were measured to test the accuracy and adaptability of Raman spectroscopy in the prediction of salmon storage time. Several preprocessing methods were compared and a novel method called long short term memory (LSTM) has been proposed and applied to spectral modeling. The results showed that the spectral bands selection of 1000–1500 cm−1 and normalization could obtain better prediction performance than other wavebands and preprocessing methods, effectively improving the accuracy of the model and reducing the predicted root mean square error (RMSE). Meanwhile, no matter at what temperature, the LSTM model was proved to have higher prediction performance and accuracy than traditional machine learning modeling methods such as support vector machine (SVM) and k-nearestneighbor (KNN). At −18 °C, the determination coefficient (R2) of the test sets in the LSTM model was 0.9986, the RMSEP was 0.24, and the prediction accuracy rate could reach 96.5%. At 4 °C, the R2, RMSEP and accuracy could reach 0.9971, 0.24 and 95% respectively. At 20 °C, the R2, RMSEP and accuracy could reach 0.999, 0.06 and 100% respectively. Therefore, Raman spectroscopy has been proven to be a stable and effective technique for predicting salmon storage time and could reach a LOD value of 0.72 day. Raman spectroscopy combined with LSTM neural network could quickly, accurately and non-destructively predict the freshness of salmon under different temperature conditions. • The storage time of salmon at different temperatures was predicted by Raman. • The LSTM method was proposed to improve the prediction performance. • Raman spectroscopy can reliably and accurately identify the freshness of salmon. [ABSTRACT FROM AUTHOR]

How to quickly and nondestructively estimate the freshness of salmon meat is necessary and urgent in the food safety market. Raman spectroscopy has become an appealing tool of freshness prediction, but its adaptability and robustness under different temperature conditions need to be further evaluated. In this paper, salmon meat samples stored at −18 °C, 4 °C and 20 °C were measured to test the accuracy and adaptability of Raman spectroscopy in the prediction of salmon storage time. Several preprocessing methods were compared and a novel method called long short term memory (LSTM) has been proposed and applied to spectral modeling. The results showed that the spectral bands selection of 1000–1500 cm−1 and normalization could obtain better prediction performance than other wavebands and preprocessing methods, effectively improving the accuracy of the model and reducing the predicted root mean square error (RMSE). Meanwhile, no matter at what temperature, the LSTM model was proved to have higher prediction performance and accuracy than traditional machine learning modeling methods such as support vector machine (SVM) and k-nearestneighbor (KNN). At −18 °C, the determination coefficient (R2) of the test sets in the LSTM model was 0.9986, the RMSEP was 0.24, and the prediction accuracy rate could reach 96.5%. At 4 °C, the R2, RMSEP and accuracy could reach 0.9971, 0.24 and 95% respectively. At 20 °C, the R2, RMSEP and accuracy could reach 0.999, 0.06 and 100% respectively. Therefore, Raman spectroscopy has been proven to be a stable and effective technique for predicting salmon storage time and could reach a LOD value of 0.72 day. Raman spectroscopy combined with LSTM neural network could quickly, accurately and non-destructively predict the freshness of salmon under different temperature conditions. • The storage time of salmon at different temperatures was predicted by Raman. • The LSTM method was proposed to improve the prediction performance. • Raman spectroscopy can reliably and accurately identify the freshness of salmon. [ABSTRACT FROM AUTHOR]