This paper studies the problem of detecting the information source in a network in which the spread of information follows the popular Susceptible-Infected-Recovered (SIR) model. We assume all nodes ...in the network are in the susceptible state initially, except one single information source that is in the infected state. Susceptible nodes may then be infected by infected nodes, and infected nodes may recover and will not be infected again after recovery. Given a snapshot of the network, from which we know the graph topology and all infected nodes but cannot distinguish susceptible nodes and recovered nodes, the problem is to find the information source based on the snapshot and the network topology. We develop a sample-path-based approach where the estimator of the information source is chosen to be the root node associated with the sample path that most likely leads to the observed snapshot. We prove for infinite-trees, the estimator is a node that minimizes the maximum distance to the infected nodes. A reverse-infection algorithm is proposed to find such an estimator in general graphs. We prove that for g+1-regular trees such that gq > 1, where g+1 is the node degree and q is the infection probability, the estimator is within a constant distance from the actual source with a high probability, independent of the number of infected nodes and the time the snapshot is taken. Our simulation results show that for tree networks, the estimator produced by the reverse-infection algorithm is closer to the actual source than the one identified by the closeness centrality heuristic. We then further evaluate the performance of the reverse infection algorithm on several real-world networks.
Aims
A meta‐analysis was conducted of the prevalence rates of compassion satisfaction, compassion fatigue and burnout to identify the factors influencing these rates.
Background
The extents of ...compassion fatigue and burnout adversely affect nursing efficiency. However, the reported prevalence rates vary considerably.
Methods
Data were acquired from electronic databases. Random effects meta‐analyses were performed to obtain pooled estimates of the prevalence rates of compassion satisfaction, compassion fatigue and burnout and their respective instrumental scores. Meta‐regression analyses were performed to identify factors influencing these rates.
Results
Data from 21 studies were used for the meta‐analysis. The prevalence rates of compassion satisfaction, compassion fatigue and burnout were 47.55%, 52.55% and 51.98%, respectively. The possession of Bachelor's or Master's degrees by the nurses was significantly inversely associated with the percent prevalence of compassion fatigue (coefficient: −1.187) and burnout (coefficient: −0.810). The compassion fatigue score was also significantly inversely associated with nursing status as registered or licensed practical nurse (coefficient: −0.135).
Conclusion
In nursing, the prevalence rates of compassion fatigue and burnout are high. Better education and training may have a moderating effect on compassion fatigue and burnout and could improve the quality of life of nurses.
The evolutionarily conserved Par3/Par6/aPKC complex regulates the polarity establishment of diverse cell types and distinct polarity-driven functions. However, how the Par complex is concentrated ...beneath the membrane to initiate cell polarization remains unclear. Here we show that the Par complex exhibits cell cycle-dependent condensation in Drosophila neuroblasts, driven by liquid-liquid phase separation. The open conformation of Par3 undergoes autonomous phase separation likely due to its NTD-mediated oligomerization. Par6, via C-terminal tail binding to Par3 PDZ3, can be enriched to Par3 condensates and in return dramatically promote Par3 phase separation. aPKC can also be concentrated to the Par3N/Par6 condensates as a client. Interestingly, activated aPKC can disperse the Par3/Par6 condensates via phosphorylation of Par3. Perturbations of Par3/Par6 phase separation impair the establishment of apical-basal polarity during neuroblast asymmetric divisions and lead to defective lineage development. We propose that phase separation may be a common mechanism for localized cortical condensation of cell polarity complexes.
Branched-chain amino acid (BCAA) metabolism is potentially linked with development of pancreatic ductal adenocarcinoma (PDAC)
. BCAA transaminase 2 (BCAT2) was essential for the collateral lethality ...conferred by deletion of malic enzymes in PDAC and the BCAA-BCAT metabolic pathway contributed to non-small-cell lung carcinomas (NSCLCs) other than PDAC
. However, the underlying mechanism remains undefined. Here we reveal that BCAT2 is elevated in mouse models and in human PDAC. Furthermore, pancreatic tissue-specific knockout of Bcat2 impedes progression of pancreatic intraepithelial neoplasia (PanIN) in LSL-Kras
; Pdx1-Cre (KC) mice. Functionally, BCAT2 enhances BCAA uptake to sustain BCAA catabolism and mitochondrial respiration. Notably, BCAA enhances growth of pancreatic ductal organoids from KC mice in a dose-dependent manner, whereas addition of branched-chain α-keto acid (BCKA) and nucleobases rescues growth of KC organoids that is suppressed by BCAT2 inhibitor. Moreover, KRAS stabilizes BCAT2, which is mediated by spleen tyrosine kinase (SYK) and E3 ligase tripartite-motif-containing protein 21 (TRIM21). In addition, BCAT2 inhibitor ameliorates PanIN formation in KC mice. Of note, a lower-BCAA diet also impedes PDAC development in mouse models of PDAC. Thus, BCAT2-mediated BCAA catabolism is critical for development of PDAC harbouring KRAS mutations. Targeting BCAT2 or lowering dietary BCAA may have translational significance.
All‐polymer solar cells (all‐PSCs) exhibit excellent stability and readily tunable ink viscosity, and are therefore especially suitable for printing preparation of large‐scale devices. At present, ...the efficiency of state‐of‐the‐art all‐PSCs fabricated by the spin‐coating method has exceeded 11%, laying the foundation for the preparation and practical utilization of printed devices. A high power conversion efficiency (PCE) of 11.76% is achieved based on PTzBI‐Si:N2200 all‐PSCs processing with 2‐methyltetrahydrofuran (MTHF, an environmentally friendly solvent) and preparation of active layers by slot die printing, which is the top efficient for all‐PSCs. Conversely, the PCE of devices processed by high‐boiling point chlorobenzene is less than 2%. Through the study of film formation kinetics, volatile solvents can freeze the morphology in a short time, and a more rigid conformation with strong intermolecular interaction combined with the solubility limit of PTzBI‐Si and N2200 in MTHF results in the formation of a fibril network in the bulk heterojunction. The multilength scaled morphology ensures fast transfer of carriers and facilitates exciton separation, which boosts carrier mobility and current density, thus improving the device performance. These results are of great significance for large‐scale printing fabrication of high‐efficiency all‐PSCs in the future.
A high power conversion efficiency of 11.76%, the best efficiency for all‐polymer solar cells, is achieved by printing fabrication based on PTzBI‐Si:N2200 processing with 2‐methyltetrahydrofuran. A Multi‐length‐scaled morphology is found in the bulk heterojunctions, which ensures fast transfer of carriers and facilitates exciton separation, and boosts carrier mobility and current density, thus improving the device performance.
Abstract
Mobile robots can be roughly categorized in wheeled type, tracked-skidded type, legged type, trunked type, etc. Among them, the wheeled mobile robot can move on the flat road, but with poor ...performance when crossing an obstacle; the legged type mobile robot has a slow motion speed and poor bearing capacity; the tracked-skidded mobile robot has a large weight; while the trunked mobile robot has limited use occasions. In order to overcome these shortcomings, this paper studies the wheel-legged structure and distributes the performance of various commonly used structures. On the other hand, by analyzing the newly emerged structure, the impact of the organization’s own shortcomings on performance is hoped to be reduced. By comparing the structure and distribution of different leg configurations, the advantages of the locomotion performance of each type of wheel-legged mobile robot and the development trend of the wheel-legged mobile robot in the future are analyzed.
A novel wide‐bandgap conjugated copolymer based on an imide‐functionalized benzotriazole building block containing a siloxane‐terminated side‐chain is developed. This copolymer is successfully used ...to fabricate highly efficient all‐polymer solar cells (all‐PSCs) processed at room temperature with the green‐solvent 2‐methyl‐tetrahydrofuran. When paired with a naphthalene diimide‐based polymer electron‐acceptor, the all‐PSC exhibits a maximum power conversion efficiency (PCE) of 10.1%, which is the highest value so far reported for an all‐PSC. Of particular interest is that the PCE remains 9.4% after thermal annealing at 80 °C for 24 h. The resulting high efficiency is attributed to a combination of high and balanced bulky charge carrier mobility, favorable face‐on orientation, and high crystallinity. These observations indicate that the resulting copolymer can be a promising candidate toward high‐performance all‐PSCs for practical applications.
A novel wide‐bandgap conjugated copolymer PTzBI‐Si based on an imide‐functionalized benzotriazole unit containing a siloxane‐terminated side‐chain is developed and used to fabricate all‐polymer solar cells (all‐PSCs). When processed with a green solvent 2‐methyl‐tetrahydrofuran, the all‐PSC exhibits a power conversion efficiency of 10.1%, which represents the highest efficiency ever reported for all‐PSCs.
Motor imagery electroencephalography (EEG) decoding is an essential part of brain-computer interfaces (BCIs) which help motor-disabled patients to communicate with the outside world by external ...devices. Recently, deep learning algorithms using decomposed spectrums of EEG as inputs may omit important spatial dependencies and different temporal scale information, thus generated the poor decoding performance. In this paper, we propose an end-to-end EEG decoding framework, which employs raw multi-channel EEG as inputs, to boost decoding accuracy by the channel-projection mixed-scale convolutional neural network (CP-MixedNet) aided by amplitude-perturbation data augmentation. Specifically, the first block in CP-MixedNet is designed to learn primary spatial and temporal representations from EEG signals. The mixed-scale convolutional block is then used to capture mixed-scale temporal information, which effectively reduces the number of training parameters when expanding reception fields of the network. Finally, based on the features extracted in previous blocks, the classification block is constructed to classify EEG tasks. The experiments are implemented on two public EEG datasets (BCI competition IV 2a and High gamma dataset) to validate the effectiveness of the proposed approach compared to the state-of-the-art methods. The competitive results demonstrate that our proposed method is a promising solution to improve the decoding performance of motor imagery BCIs.
SUMMARY
Abscisic acid (ABA) is involved in salt and drought stress responses, but the underlying molecular mechanism remains unclear. Here, we demonstrated that the overexpression of MdMYB44‐like, an ...R2R3‐MYB transcription factor, significantly increases the salt and drought tolerance of transgenic apples and Arabidopsis. MdMYB44‐like inhibits the transcription of MdPP2CA, which encodes a type 2C protein phosphatase that acts as a negative regulator in the ABA response, thereby enhancing ABA signaling‐mediated salt and drought tolerance. Furthermore, we found that MdMYB44‐like and MdPYL8, an ABA receptor, form a protein complex that further enhances the transcriptional inhibition of the MdPP2CA promoter by MdMYB44‐like. Significantly, we discovered that MdPP2CA can interfere with the physical association between MdMYB44‐like and MdPYL8 in the presence of ABA, partially blocking the inhibitory effect of the MdMYB44‐like–MdPYL8 complex on the MdPP2CA promoter. Thus, MdMYB44‐like, MdPYL8, and MdPP2CA form a regulatory loop that tightly modulates ABA signaling homeostasis under salt and drought stress. Our data reveal that MdMYB44‐like precisely modulates ABA‐mediated salt and drought tolerance in apples through the MdPYL8–MdPP2CA module.
Significance Statement
Under salt and drought stress, ABA promotes MdMYB44‐like gene expression, and MdPYL8 interacts with MdMYB44‐like to form a protein complex that further strengthens the transcriptional inhibition of MdMYB44‐like on the MdPP2CA promoter. Interestingly, MdPP2CA interferes with the interaction between MdMYB44‐like and MdPYL8 in the presence of ABA, thereby reducing the transcriptional inhibition of MdPP2CA by the MdMYB44‐like‐MdPYL8 complex and thus balancing ABA signaling in plants.
This paper investigates the relation between three different notions of privacy: identifiability, differential privacy, and mutual-information privacy. Under a unified privacydistortion framework, ...where the distortion is defined to be the expected Hamming distance between the input and output databases, we establish some fundamental connections between these three privacy notions. Given a maximum allowable distortion D, we define the privacy-distortion functions ∈ i * (D), ∈ d *(D), and ∈ m *(D) to be the smallest (most private/best) identifiability level, differential privacy level, and mutual information between the input and the output, respectively. We characterize ∈ i * (D) and ∈ d *(D), and prove that ∈ i * (D) - ∈ X ≤ ∈ d *(D) ≤ ∈ i * (D) for D within certain range, where ∈ X is a constant determined by the prior distribution of the original database X, and diminishes to zero when X is uniformly distributed. Furthermore, we show that ∈ i * (D) and ∈ m *(D) can be achieved by the same mechanism for D within certain range, i.e., there is a mechanism that simultaneously minimizes the identifiability level and achieves the best mutual-information privacy. Based on these two connections, we prove that this mutual-information optimal mechanism satisfies ∈-differential privacy with ∈ d *(D) ≤ ∈ ≤ ∈ d *(D)+2∈ X . The results in this paper reveal some consistency between two worst case notions of privacy, namely, identifiability and differential privacy, and an average notion of privacy, mutual-information privacy.
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