4 research outputs found
Recent Progress in Transformer-based Medical Image Analysis
The transformer is primarily used in the field of natural language
processing. Recently, it has been adopted and shows promise in the computer
vision (CV) field. Medical image analysis (MIA), as a critical branch of CV,
also greatly benefits from this state-of-the-art technique. In this review, we
first recap the core component of the transformer, the attention mechanism, and
the detailed structures of the transformer. After that, we depict the recent
progress of the transformer in the field of MIA. We organize the applications
in a sequence of different tasks, including classification, segmentation,
captioning, registration, detection, enhancement, localization, and synthesis.
The mainstream classification and segmentation tasks are further divided into
eleven medical image modalities. A large number of experiments studied in this
review illustrate that the transformer-based method outperforms existing
methods through comparisons with multiple evaluation metrics. Finally, we
discuss the open challenges and future opportunities in this field. This
task-modality review with the latest contents, detailed information, and
comprehensive comparison may greatly benefit the broad MIA community.Comment: Computers in Biology and Medicine Accepte
Distribution and Supply of Antimony Resources in China and Abroad and Development Status of Antimony Industry Chain
Antimony is an important raw material for industrial production which is widely used and irreplaceable. With the development of lead battery, flame retardant, alloy, semiconductor, catalyst, microcrystalline glass, chemical, military and other industries, coupled with the impact of the new crown epidemic on the global social and economic and international environmental uncertainty, strategic position of antimonyis highlighted. This paper systematically summarizes the distribution and supply, industry chain status and future development trend of antimony in China and abroad. The research shows that China's antimony resources occupy a dominant position, China's antimony has high production and consumption, the proportion of high-end products in China's antimony industry chain is not high, the demand for antimony resources has a strong growth space, and worldwide demand for antimony will remain stable over the next decade. Suggestions on strengthening domestic antimony prospecting, strengthening foreign resources development, increasing technology research and development, promoting green development of antimony industry, trengthening industrial chain integration, promoting high-quality development of application end, formulating strategic reserve system, implementing strategic reserve of antimony resources are put forward
Size Effects of Microplastics on Embryos and Observation of Toxicity Kinetics in Larvae of Grass Carp (Ctenopharyngodon idella)
Microplastics have caused great concern in recent years. However, few studies have compared the toxicity of different sizes of microplastics in fishes, especially commercial fishes, which are more related to human health. In the present study, we revealed the effects of varying sizes of microplastics on grass carp embryos and larvae using scanning electron microscopy (SEM) and fluorescence imaging. Embryos were exposed to 80 nm and 8 μm microplastics at concentrations of 5, 15, and 45 mg/L. Toxicity kinetics of various sizes of fluorescent microplastics were analyzed through microscopic observation in the larvae. Results found that nanoplastics could not penetrate the embryo’s chorionic membrane, instead they conglutinated or aggregated on the chorion. Our results are the first to explore the defense mechanisms of commercial fish embryos against microplastics. Larvae were prone to ingesting their own excrement, resulting in microplastic flocculants winding around their mouth. For the first time, it was found that excreted microplastics could be reconsumed by fish and reaccumulated in the oral cavity. Microplastics of a certain size (1 μm) could be accumulated in the nasal cavity. We speculate that the presence of a special groove structure in the nasal cavity of grass carp larvae may manage to seize the microplastics with a particular size. As far as we know, this is the first report of microplastics being found in the nasal passages of fish. Fluorescence images clearly recorded the toxicity kinetics of microplastics in herbivorous fish
Molecular-Weight Dependence of Center-of-Mass Chain Diffusion in Polymerized Ionic Liquid Melts
Polymerized ionic liquids (PILs) with flexible polymer
chains and
weakly interacting ionic liquid (IL) groups have received great attention
for their desirable properties in electrochemical applications such
as ionic conductivity. Less is known about their dynamic properties
such as center-of-mass chain diffusion and how it depends on molecular
weight in the presence of IL groups. In this work, a series of acrylic
PILs with imidazolium cations and bis(trifluoromethanesulfonyl)imide
(TFSI) anions (TFSI-f-PILN) were synthesized
via reversible addition–fragmentation chain-transfer polymerization
with degrees of polymerization N ranging from 40
to 236. A fluorescent acrylic monomer with the 7-nitrobenzofurazan
group was copolymerized at trace levels as a probe of chain motion,
and the diffusion coefficient (D) of TFSI-f-PILN was determined by fluorescence recovery
after photo bleaching at Tg + 45 K. Within
the uncertainty of 3–20%, a scaling relationship of D ∼ N–2 was observed
which is the same as the scaling of linear neutral polymers. Wide-angle
X-ray scattering exhibited no peak at ∼5 nm–1, indicating no long-range imidazolium-TFSI ionic correlations. Our
results indicate that the molecular weight dependence of center-of-mass
diffusion is not affected by electrostatic interactions of IL groups.
No transition from a Rouse regime (D ∼ N–1) to reptation regime (D ∼ N–2) was observed within
the studied N range