Not Just Learning from Others but Relying on Yourself: A New Perspective on Few-Shot Segmentation in Remote Sensing

Few-shot segmentation (FSS) is proposed to segment unknown class targets with just a few annotated samples. Most current FSS methods follow the paradigm of mining the semantics from the support images to guide the query image segmentation. However, such a pattern of `learning from others' struggles to handle the extreme intra-class variation, preventing FSS from being directly generalized to remote sensing scenes. To bridge the gap of intra-class variance, we develop a Dual-Mining network named DMNet for cross-image mining and self-mining, meaning that it no longer focuses solely on support images but pays more attention to the query image itself. Specifically, we propose a Class-public Region Mining (CPRM) module to effectively suppress irrelevant feature pollution by capturing the common semantics between the support-query image pair. The Class-specific Region Mining (CSRM) module is then proposed to continuously mine the class-specific semantics of the query image itself in a `filtering' and `purifying' manner. In addition, to prevent the co-existence of multiple classes in remote sensing scenes from exacerbating the collapse of FSS generalization, we also propose a new Known-class Meta Suppressor (KMS) module to suppress the activation of known-class objects in the sample. Extensive experiments on the iSAID and LoveDA remote sensing datasets have demonstrated that our method sets the state-of-the-art with a minimum number of model parameters. Significantly, our model with the backbone of Resnet-50 achieves the mIoU of 49.58% and 51.34% on iSAID under 1-shot and 5-shot settings, outperforming the state-of-the-art method by 1.8% and 1.12%, respectively. The code is publicly available at https://github.com/HanboBizl/DMNet.Comment: accepted to IEEE TGR

DePARylation Is Critical for S Phase Progression and Cell Survival

Poly(ADP-ribose)ylation or PARylation by PAR polymerase 1 (PARP1) and dePARylation by poly(ADP-ribose) glycohydrolase (PARG) are equally important for the dynamic regulation of DNA damage response. PARG, the most active dePARylation enzyme, is recruited to sites of DNA damage via pADPr-dependent and PCNA-dependent mechanisms. Targeting dePARylation is considered an alternative strategy to overcome PARP inhibitor resistance. However, precisely how dePARylation functions in normal unperturbed cells remains elusive. To address this challenge, we conducted multiple CRISPR screens and revealed that dePARylation of S phase pADPr by PARG is essential for cell viability. Loss of dePARylation activity initially induced S-phase-specific pADPr signaling, which resulted from unligated Okazaki fragments and eventually led to uncontrolled pADPr accumulation and PARP1/2-dependent cytotoxicity. Moreover, we demonstrated that proteins involved in Okazaki fragment ligation and/or base excision repair regulate pADPr signaling and cell death induced by PARG inhibition. In addition, we determined that PARG expression is critical for cellular sensitivity to PARG inhibition. Additionally, we revealed that PARG is essential for cell survival by suppressing pADPr. Collectively, our data not only identify an essential role for PARG in normal proliferating cells but also provide a potential biomarker for the further development of PARG inhibitors in cancer therapy

Fusarium pseudograminearum biomass and toxin accumulation in wheat tissues with and without Fusarium crown rot symptoms

Fusarium crown rot (FCR) is an important and devastating disease of wheat (Triticum aestivum) caused by the fungus Fusarium pseudograminearum and related pathogens. Using two distinct susceptible cultivars, we investigated the isolation frequencies of F. pseudograminearum and quantified its biomass accumulation and the levels of the associated toxins deoxynivalenol (DON) and DON-3-glucoside (D3G) in inoculated field-grown wheat plants. We detected F. pseudograminearum in stem, peduncle, rachis, and husk tissues, but not in grains, whereas DON and D3G accumulated in stem, rachis, husk, and grain tissues. Disease severity was positively correlated with the frequency of pathogen isolation, F. pseudograminearum biomass, and mycotoxin levels. The amount of F. pseudograminearum biomass and mycotoxin contents in asymptomatic tissue of diseased plants were associated with the distance of the tissue from the diseased internode and the disease severity of the plant. Thus, apparently healthy tissue may harbor F. pseudograminearum and contain associated mycotoxins. This research helps clarify the relationship between F. pseudograminearum occurrence, F. pseudograminearum biomass, and mycotoxin accumulation in tissues of susceptible wheat cultivars with or without disease symptoms, providing information that can lead to more effective control measures

Electric control of spin polarization orientation in a magnetic-electric barrier structure

We investigate spin-dependent transport properties of two-dimensional electron systems modulated by both the stray field from a ferromagnetic metal (FM) stripe and the electrostatic potential (EP) provided by two normal metal Schottky stripes which sandwich the FM stripe. The EP consists of a single barrier and a single well. By switching the gate voltages applied to the Schottky stripes, the barrier and the well exchange their positions. Accordingly, the spatial region, where spin-dependent resonant tunneling happens, is transferred from one side of the FM stripe to the other, resulting in a rotation or a reversal of the spin polarization orientation. (C) 2007 Elsevier B.V. All rights reserved

Symmetry of spin transport in two-terminal waveguides with a spin-orbital interaction and magnetic field modulations

We analyze symmetries of spin transport in two-terminal quantum waveguide structures with Rashba spin-orbit coupling and magnetic field modulations. Constraints, imposed by the device structure, on the spin polarization of the transmitted electron beam from the waveguide devices are derived. The results are expected to provide accuracy tests for experimental measurements and numerical calculations, as well as guidelines for spin-based device designs

Spin filtering in single magnetic barrier structures revisited

We reexamine spin-dependent transport properties of two-dimensional electrons modulated by the stray field of a ferromagnetic metal (FM) stripe on top. When the magnetization is along the transport direction of the electrons, the FM stripe generates not only a magnetic barrier but also an in-plane magnetic field component. Previous studies have omitted the in-plane magnetic field component and shown that such a device does not possess any spin-filtering effect. We show that with inclusion of this in-plane magnetic field component, a spin polarization of nearly 100% can be achieved in such a single FM-stripe modulated two-dimensional electron gas device

Spin filtering and spin accumulation in an electron stub waveguide with spin-orbit interaction

We investigate spin-dependent transport properties of a two-terminal electron waveguide, attached with a side arm, with Rashba spin-orbit interaction (SOI). The interference between the bound states in the side arm and the continuous states in the straight channel gives rise to broad valleys in the conductance spectrum. At these Fano antiresonances, a large transverse spin polarization can be created by the SOI-induced effective magnetic field. The magnitude of the spin polarization in this waveguide structure can be electrically tuned by variation of the stub length or the SOI strength, suggesting that the SOI-modulated stub waveguide structure can be used as an electrically tunable spin filter. It is also found that highly polarized spin-density islands can form inside the stub. Thus the stub waveguide structure could also be utilized to create local magnetic moments and for information storage

Coexistence of a single cerebral arteriovenous malformation and spinal arteriovenous malformation

The coexistence of a cerebral and a spinal arteriovenous malformation (AVM) together is extremely rare. We present a 31-year-old woman, who suffered from severe root pains in the left upper extremity. Magnetic resonance imaging (MRI) revealed the abnormal vessels in the left occipital lobe and upper cervical segment of spinal cord. Cerebral angiography and spinal angiogram revealed two AVMs: One was in the right occipital lobe and the other was located in the C1-C2 segments of cervical cord. She had no other vascular lesions, and nor did her other family members. As the primary problem in her was left upper extremity root pains, which we considered was related to the spinal AVM, the first therapeutic treatment was focused on spinal AVM. The cerebral AVM of the right occipital lobe was surgically resected after part embolization