Plants must effectively defend against biotic and abiotic stresses to survive in nature. However, this defense is costly and is often accompanied by significant growth inhibition. How plants ...coordinate the fluctuating growth-defense dynamics is not well understood and remains a fundamental question. Jasmonate (JA) and gibberellic acid (GA) are important plant hormones that mediate defense and growth, respectively. Binding of bioactive JA or GA ligands to cognate receptors leads to proteasome-dependent degradation of specific transcriptional repressors (the JAZ or DELLA family of proteins), which, at the resting state, represses cognate transcription factors involved in defense (e.g., MYCs) or growth e.g. phytochrome interacting factors (PIFs). In this study, we found that the coi1 JA receptor mutants of rice (a domesticated monocot crop) and Arabidopsis (a model dicot plant) both exhibit hallmark phenotypes of GA-hypersensitive mutants. JA delays GA-mediated DELLA protein degradation, and the della mutant is less sensitive to JA for growth inhibition. Overexpression of a selected group of JAZ repressors in Arabidopsis plants partially phenocopies GA-associated phenotypes of the coi1 mutant, and JAZ9 inhibits RGA (a DELLA protein) interaction with transcription factor PIF3. Importantly, the pif quadruple (pifq) mutant no longer responds to JA-induced growth inhibition, and overexpression of PIF3 could partially overcome JA-induced growth inhibition. Thus, a molecular cascade involving the COI1–JAZ–DELLA–PIF signaling module, by which angiosperm plants prioritize JA-mediated defense over growth, has been elucidated.
Numerous studies have shown the positive correlation between high levels of Pi and tumour progression. A critical goal of macrophage-based cancer therapeutics is to reduce anti-inflammatory ...macrophages (M2) and increase proinflammatory antitumour macrophages (M1). This study aimed to investigate the relationship between macrophage polarization and low-Pi stress. First, the spatial populations of M2 and M1 macrophages in 22 HCC patient specimens were quantified and correlated with the local Pi concentration. The levels of M2 and M1 macrophage markers expressed in the peritumour area were higher than the intratumour levels, and the expression of M2 markers was positively correlated with Pi concentration. Next, monocytes differentiated from THP-1 cells were polarized against different Pi concentrations to investigate the activation or silencing of the expression of p65, IκB-α and STAT3 as well as their phosphorylation. Results showed that low-Pi stress irreversibly repolarizes tumour-associated macrophages (TAMs) towards the M1 phenotype by silencing stat6 and activating p65. Moreover, HepG-2 and SMCC-7721 cells were cultured in conditioned medium to investigate the innate anticancer immune effects on tumour progression. Both cancer cell lines showed reduced proliferation, migration and invasion, as epithelial-mesenchymal transition (EMT) was inactivated. In vivo therapeutic effect on the innate and adaptive immune processes was validated in a subcutaneous liver cancer model by the intratumoural injection of sevelamer. Tumour growth was significantly inhibited by the partial deprivation of intratumoural Pi as the tumour microenvironment under low-Pi stress is more immunostimulatory. The anticancer immune response, activated by low-Pi stress, suggests a new macrophage-based immunotherapeutic modality.
Source-specific risk apportionment for soil heavy metals (HMs) is crucial for pollution mitigation and risk control in coal-mining areas. The ecological and human health risks resulting from ...different sources were evaluated through an integrated method that combines risk assessments with positive matrix factorization (PMF) model. Thirty soil samples were collected from a typical coal-mining city in central China and analyzed for six HMs (Cu, Ni, Pb, Cd, As, and Hg). The results indicate that surface soil in the study area suffered from moderate HMs pollution, especially pollution by Cd and Hg. Four potential sources of soil HMs were identified and quantified in the study area, including natural source (27.7%), traffic emissions (33.4%), agricultural practices (16.2%), and industrial activities (22.7%). The ecological risk of the study area was at moderate level, and the leading contributions in urban and suburban areas were from industrial activities and agricultural practices, respectively. The non-carcinogenic risks for adults and children were lower than the risk threshold, while the carcinogenic risks ranged between 1E−06 and 1E−04, suggesting that carcinogenic risks and hazards to human health should not be neglected. Traffic emissions and natural sources mainly contributed to the non-carcinogenic and carcinogenic risks, due to the strong non-carcinogenicity and carcinogenicity of As and Ni. These findings highlight the ecological and health risks linked to potential sources of soil HMs contamination and provide valuable information on the reduction of corresponding risks for local environmental managers.
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•Moderate soil contamination by Cd and Hg is identified in the study area.•Source-specific risks are apportioned using PMF-based risk assessment methods.•The source profiles of potential ecological risks vary in urban and suburban areas.•Human health risks posed by soil HMs are mainly from traffic and natural sources.
Ultrathin 2D organic nanosheets (2DONs) with high mobility have received tremendous attention due to thickness of few molecular layers. However, ultrathin 2DONs with high luminescence efficiency and ...flexibility simultaneously are rarely reported. Here, the ultrathin 2DONs (thickness: 19 nm) through the modulation of tighter molecular packing (distance: ≈3.31 Å) achievable from the incorporation of methoxyl and dipenylamine (DPA) groups into 3D spirofluorenexanthene (SFX) building blocks is successfully prepared. Even with closer molecular stacking, ultrathin 2DONs still enable the suppression of aggregation quenching to exhibit higher quantum yields of blue emission (ΦF = 48%) than that on amorphous film (ΦF = 20%), and show amplified spontaneous emission (ASE) with a mediate threshold (332 mW cm−2). Further, through drop‐casting method, the ultrathin 2DONs are self‐organized into large‐scale flexible 2DONs films (1.5 × 1.5 cm) with the low hardness (H: 0.008 Gpa) and low Young's modulus (Er: 0.63 Gpa). Impressively, the large‐scale 2DONs film can realize electroluminescence performances with a maximum luminance (445 cd m−2) and low turn on voltage (3.7 V). These ultrathin 2DONs provide a new avenue for the realization of flexible electrically pumping lasers and intelligent quantum tunneling systems.
Ultrathin (19 nm), high luminescence (48%), and flexible 2D organic nanosheets (2DONs) are synthesized. And the large‐scale 2DONs film also is achieved via hierarchically self‐organized process based on eco‐friendly aqueous 2DONs ink. The use of 2DONs film as emissive layer exhibits stable blue emission and low turn on voltage (3.7 V) in electroluminescent devices.
Current methods for few-shot segmentation (FSSeg) have mainly focused on improving the performance of novel classes while neglecting the performance of base classes. To overcome this limitation, the ...task of generalized few-shot semantic segmentation (GFSSeg) has been introduced, aiming to predict segmentation masks for both base and novel classes. However, the current prototype-based methods do not explicitly consider the relationship between base and novel classes when updating prototypes, leading to a limited performance in identifying true categories. To address this challenge, we propose a class contrastive loss and a class relationship loss to regulate prototype updates and encourage a large distance between prototypes from different classes, thus distinguishing the classes from each other while maintaining the performance of the base classes. Our proposed approach achieves new state-of-the-art performance for the generalized few-shot segmentation task on PASCAL VOC and MS COCO datasets.
To investigate the feasibility and clinical utility of a compressed-sensing-accelerated subtractionless whole-body MRA (CS-WBMRA) protocol with only contrast injection for suspected arterial ...diseases, by comparison to conventional dual-pass subtraction-based whole-body MRA (conventional-WBMRA) and available computed tomography angiography (CTA).
This prospective study assessed 86 patients (mean age, 56 years ± 16.4 standard deviation; 25 women) with suspected arterial diseases from May 2021 to December 2022, who underwent CS-WBMRA (n = 48, mean age, 55.9 years ± 16.4 standard deviation; 25 women) and conventional-WBMRA (n = 38, mean age, 48 years ± 17.4 standard deviation; 20 women) on a 3.0 T MRI after random group assignment based on the chronological order of enrolment. Of all enrolled patients administered the CS-WBMRA protocol, 35% (17/48) underwent CTA as required by clinical demands. Two experienced radiologists independently scored the qualitative image quality and venous enhancement contamination. Quantitative image assessment was carried out by determining and comparing the apparent signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of four representative arterial segments. The total examination time and contrast-dose were also recorded. The independent samples t-test or the Wilcoxon rank sum test was used for statistical analysis.
The overall scores of CS-WBMRA outperformed those of conventional-WMBRA (3.40 ± 0.60 vs 3.22 ± 0.55, P < 0.001). In total, 1776 and 1406 arterial segments in the CS-WBMRA and conventional-WBMRA group were evaluated. Qualitative image scores for 7 (of 15) vessel segments in the CS-WMBRA group had statistically significantly increased values compared to those of the conventional-WBMRA groups (P < 0.05). Scores from the other 8 segments showed similar image quality (P > 0.05) between the two protocols. In the quantitative analysis, overall apparent SNRs were significantly higher in the conventional-WBMRA group than in the CS-WBMRA group (214.98 ± 136.05 vs 164.90 ± 118.05; P < 0.001), while overall apparent CNRs were not significantly different in these two groups (CS vs conventional: 107.13 ± 72.323 vs 161.24 ± 118.64; P > 0.05). In the CS-WBMRA group, 7 of 1776 (0.4%) vessel segments were contaminated severely by venous enhancement, while in the convention-WBMRA group, 317 of 1406 (23%) were rated as severe contamination. In the CS-WBMRA group, total examination and reconstruction times were only 7 min and 10 min, respectively, vs 20 min and < 30 s for the conventional WBMRA group, respectively. The contrast agent dose used in the CS-WBMRA protocol was reduced by half compared to conventional-WBMRA protocol (18.7 ± 3.5 ml vs 37.2 ± 5.4 ml, P = 0.008).
The CS-WBMRA protocol provides excellent image quality and sufficient diagnostic accuracy for whole-body arterial disease, with relatively faster workflow and half-dose reduction of contrast agent, which has greater potential in clinical practice compared with conventional-WBMRA.
A phase-controlled ultralow-threshold phonon laser is proposed by using tunable optical amplifiers in coupled-cavity-optomechanical system. The multiplicative behavior of the individual enhancements, ...by engineering the phases and strengths of external parametric driving, makes it possible to achieve the strong-coupling regime of optomechanics, where the switching among radiation-pressure, parametric amplification, and three-mode optomechanical couplings can be realized and ultralow-threshold phonon lasing is observable. This opens up novel prospects for applications in, e.g. quantum acoustics, nonlinear phonon devices, and ultrasensitive motion sensing.
With mixed transition-metal-complex, alkali-metal, or organic cations as structure-directing agents, a series of novel two-dimensional (2D) layered inorganic–organic hybrid iodoargentates, namely, K ...x TM(2,2-bipy)32Ag6I11 (TM = Mn (1), Fe (2), Co (3), Ni (4), Zn (5); x = 0.89–1) and (Ni(2,2-bipy)3H-2,2-bipyAg3I6 (6), have been solvothermally synthesized and structurally characterized. All the title compounds feature 2D microporous layers composed by Ag3I7 secondary building units based on AgI4 tetrahedra. Differently, the Ag3I7 trimers are directly interconnected via corner-sharing to form the 2D Ag6I115– layer in compounds 1–5, whereas two neighboring Ag3I7 trimers are initially condensed into a hexameric Ag6I12 ternary building unit as a new node, which further self-assembles, leading to the 2D Ag6I104– layer in compound 6. The UV–vis diffuse-reflectance measurements reveal that all the compounds possess proper semiconductor behaviors with tunable band gaps of 1.66–2.75 eV, which lead to highly efficient photocatalytic degradation activities over organic pollutants under visible light irradiation compared to that of N-dotted P25. Interestingly, all the samples feature distinct photodegradative speeds at the same reaction conditions, and compound 1 features the highest photocatalytic activity among the title phases. The luminescence properties, band structures, and thermal stabilities were also studied.
In the field of structural health monitoring (SHM), with the mature development of artificial intelligence, deep learning-based structural damage identification techniques have attracted wide ...attention. In this paper, the convolutional neural network (CNN) is used to extract the damage feature of simple supported steel beams. Firstly, the transient dynamic analysis of the steel beam is carried out by finite element software, and the acceleration response signals under different damage scenarios are obtained. Then, the acceleration response signal is decomposed by wavelet packet decomposition (WPD) to extract the wavelet packet band energy ratio variation (ERV) index as the training sample of CNN. Subsequently, the vibration experiment of a simple supported steel beam was carried out, and the results were compared with the numerical simulation results. The characteristic indexes were obtained by making corresponding changes to the vibration signal, and then, the experimental data were input into the CNN to predict the effect of damage detection. The results show that the method can successfully detect the intact structure, single damage, and multiple damages with an accuracy of 95.14% under impact load, and the performance is better than that of support vector machine (SVM), with good robustness.
Neural networks are capable of learning complex concepts and tasks, given abundant training data. In real-world applications where data collection can be difficult, integrating domain knowledge into ...the model can reduce the burden on data requirements and allow human experts greater control over model decisions. This paper focuses on incorporating conditional statements for tabular data as classification rules, which have a simple structure and are easy to construct. We introduce a general rule loss constraint to guide neural network training in a model agnostic manner, and propose confidence learning to automatically weigh the contribution of multiple candidate rules. Experimental evaluation with three real-world datasets shows that the rule loss can substantially increase model performance, particularly when training data is limited.
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