147 research outputs found
FEC: Three Finetuning-free Methods to Enhance Consistency for Real Image Editing
Text-conditional image editing is a very useful task that has recently
emerged with immeasurable potential. Most current real image editing methods
first need to complete the reconstruction of the image, and then editing is
carried out by various methods based on the reconstruction. Most methods use
DDIM Inversion for reconstruction, however, DDIM Inversion often fails to
guarantee reconstruction performance, i.e., it fails to produce results that
preserve the original image content. To address the problem of reconstruction
failure, we propose FEC, which consists of three sampling methods, each
designed for different editing types and settings. Our three methods of FEC
achieve two important goals in image editing task: 1) ensuring successful
reconstruction, i.e., sampling to get a generated result that preserves the
texture and features of the original real image. 2) these sampling methods can
be paired with many editing methods and greatly improve the performance of
these editing methods to accomplish various editing tasks. In addition, none of
our sampling methods require fine-tuning of the diffusion model or
time-consuming training on large-scale datasets. Hence the cost of time as well
as the use of computer memory and computation can be significantly reduced
RGM: A Robust Generalist Matching Model
Finding corresponding pixels within a pair of images is a fundamental
computer vision task with various applications. Due to the specific
requirements of different tasks like optical flow estimation and local feature
matching, previous works are primarily categorized into dense matching and
sparse feature matching focusing on specialized architectures along with
task-specific datasets, which may somewhat hinder the generalization
performance of specialized models. In this paper, we propose a deep model for
sparse and dense matching, termed RGM (Robust Generalist Matching). In
particular, we elaborately design a cascaded GRU module for refinement by
exploring the geometric similarity iteratively at multiple scales following an
additional uncertainty estimation module for sparsification. To narrow the gap
between synthetic training samples and real-world scenarios, we build a new,
large-scale dataset with sparse correspondence ground truth by generating
optical flow supervision with greater intervals. As such, we are able to mix up
various dense and sparse matching datasets, significantly improving the
training diversity. The generalization capacity of our proposed RGM is greatly
improved by learning the matching and uncertainty estimation in a two-stage
manner on the large, mixed data. Superior performance is achieved for zero-shot
matching and downstream geometry estimation across multiple datasets,
outperforming the previous methods by a large margin.Comment: 17 pages. Fixed typo in the first two equations. Code is available
at: https://github.com/aim-uofa/RG
Visible-telecom broadband optical isolator based on dynamic modulation in thin-film lithium niobate
Optical isolators are an essential component of photonic systems. Current
integrated optical isolators have limited bandwidths due to stringent
phase-matching conditions, resonant structures, or material absorption. Here,
we demonstrate an ultra-broadband integrated optical isolator in thin-film
lithium niobate photonics. We use dynamic standing-wave modulation in a tandem
configuration to break Lorentz reciprocity and achieve isolation. We measure an
isolation ratio of 15 dB and insertion loss below 0.5 dB for a design
wavelength of 1550 nm. In addition, we experimentally show that this isolator
can simultaneously operate at visible and telecom wavelengths with comparable
performance. Isolation bandwidths ~100 nm can be achieved simultaneously at
both visible and telecom wavelengths. Our device's large bandwidth, high
flexibility, and real-time tunability can enable novel non-reciprocal
functionality on integrated photonic platforms
Improving Linewidth and Extinction Ratio Performances of Lithium Niobate Ring Modulator Using Ring-pair Structure
Electro-optic modulators lie at the heart of complex integration and high
density electro-optic systems. One of the representative electro-optic
modulators is thin film lithium niobate based microring modulator which has
demonstrated advantages of compact footprint, low optical loss and high
modulation efficiency. However, the linewidth and extinction ratio of ring
modulators are fundamentally limited by the ring losses and coupling,
respectively. To this end, we propose a novel type of electro-optic modulators
with ring-pair structure on thin film lithium niobate platform, which brings
substantially improvement of linewidth and extinction ratio. The ring-pair
modulator exhibits a larger linewidth up to 22 GHz, 1.74-time larger than that
of single ring resonator with same design parameters. Moreover, the
experimental results also reveal that the added-up extinction ratio of
ring-pair resonator goes beyond 30 dB, much larger than that in an individual
ring resonator. These advantages of ring-pair modulator pave a new way for the
application of compact ring-based modulators with large working wavelength
window and high extinction ratio, to be exploited in quantum optics,
programmable nanophotonics and optical sensors, etc.Comment: 14 page
Epitaxial Growth of Germanium on Silicon for Light Emitters
National Basic Research Program of China [2007CB613404, 2012CB933503]; National Natural Science Foundation of China [61036003, 60837001, 61176092]; Fundamental Research Funds for the Central Universities [2010121056]This paper describes the role of Ge as an enabler for light emitters on a Si platform. In spite of the large lattice mismatch of similar to 4.2% between Ge and Si, high-quality Ge layers can be epitaxially grown on Si by ultrahigh-vacuum chemical vapor deposition. Applications of the Ge layers to near-infrared light emitters with various structures are reviewed, including the tensile-strained Ge epilayer, the Ge epilayer with a delta-doping SiGe layer, and the Ge/SiGe multiple quantum wells on Si. The fundamentals of photoluminescence physics in the different Ge structures are discussed briefly
Crust-Mantle Interaction Controls the Formation of High-Mg Adakitic Rocks: Evidence from Early Cretaceous Intrusive Complexes in Luxi Terrane, North China Craton
High-Mg adakite rocks preserve crucial information about the crust-mantle interactions during the magma evolution. The Luxi Terrane, southeastern North China Craton, stores a set of Early Cretaceous high-Mg adakite rocks; nevertheless, their petrogenesis remains controversial. In this study, we present new whole-rock geochemistry, zircon U-Pb-Hf isotopes in the Tiezhai, Jinxingtou, and Sanshanyu complexes which are composed of gabbroic diorite, diorites, syenites, and monzonites. Field observations and zircon U-Pb dating indicate that all of the rock units crystallized contemporaneously at ca. 125–120 Ma. They are characterized by high Al2O3 and Sr contents, and low MgO, Y, Yb, and heavy rare earth elements contents, coupled with high Sr/Y values (42–163), showing adakitic affinities. The magma mixing process is supported by the following ample evidence: (1) the disequilibrium mineral textures and mafic enclaves; (2) high Mg# values (37–69, Mean = 58); and (3) widely zircons εHf(t) values (−25.6 to +7.8). The signature geochemical characteristics support that the adakites were generated by magma mixing of ancient crust-derived melts and relatively mafic melts from metasomatized mantle source. In combined with regional geology, the Early Cretaceous high-Mg adakites in Luxi Terrane represent the magmatic response of intensive crust-mantle interaction caused by the underplating of voluminous mantle-derived magma in an extension intracontinental setting
The role of miR-143-3p/FNDC1 axis on the progression of non-small cell lung cancer
The study aimed to explore the functional role of fibronectin type III domain containing 1 (FNDC1) in nonsmall cell lung cancer (NSCLC), as well as the mechanism governing its expression. The expression levels of FNDC1 and related genes in tissue and cell samples were detected by qRT-PCR. Kaplan-Meier analysis was employed to analyze the association between FNDC1 level and the overall survival of NSCLC patients. Functional experiments such as CCK-8 proliferation, colony formation, EDU staining, migration and invasion assays were conducted to investigate the functional role of FNDC1 in regulating the malignancy of NSCLC cells. Bioinformatic tools and dual-luciferase reporter assay were used to identify the miRNA regulator of FNDC1 in NSCLC cells. Our data revealed the upregulation of FNDC1 at mRNA and protein levels in NSCLC tumor tissues cancer cell lines, compared with normal counterparts. NSCLC patients with higher FNDC1 expression suffered from a poorer overall survival. FNDC1 knockdown significantly suppressed the proliferation, migration and invasion of NSCLC cells, and had an inhibitory effect on tube formation. We further demonstrated that miR-143-3p was an upstream regulator of FNDC1 and miR-143-3p expression was repressed in NSCLC samples. Similar to FNDC1 knockdown, miR-143-3p overexpression inhibited the growth, migration and invasion of NSCLC cells. FNDC1 overexpression could partially rescue the effect of miR-143-3p overexpression. FNDC1 silencing also suppressed the tumorigenesis of NSCLC cells in mouse model. In conclusion, FNDC1 promotes the malignant prototypes of NSCLC cells. miR-143-3p is a negative regulator of FNDC1 in NSCLC cells, which may serve as a promising therapeutic target in NSCLC.
Preparation for SiGe/Si heterogeneous nanostructures via a two-step approach strategy
SiGe/Si heterogeneous nanostructures were prepared by electrochemical anodization of SiGe/Si MQWs. Structural and optical properties of the materials were characterized. The origin of the photoluminescence from the heterogeneous nanostructures at room temperature is discussed
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