280 research outputs found
Sim-to-Real Segmentation in Robot-assisted Transoral Tracheal Intubation
Robotic-assisted tracheal intubation requires the robot to distinguish
anatomical features like an experienced physician using deep-learning
techniques. However, real datasets of oropharyngeal organs are limited due to
patient privacy issues, making it challenging to train deep-learning models for
accurate image segmentation. We hereby consider generating a new data modality
through a virtual environment to assist the training process. Specifically,
this work introduces a virtual dataset generated by the Simulation Open
Framework Architecture (SOFA) framework to overcome the limited availability of
actual endoscopic images. We also propose a domain adaptive Sim-to-Real method
for oropharyngeal organ image segmentation, which employs an image blending
strategy called IoU-Ranking Blend (IRB) and style-transfer techniques to
address discrepancies between datasets. Experimental results demonstrate the
superior performance of the proposed approach with domain adaptive models,
improving segmentation accuracy and training stability. In the practical
application, the trained segmentation model holds great promise for
robot-assisted intubation surgery and intelligent surgical navigation.Comment: Extended abstract in IEEE ICRA 2023 Workshop (New Evolutions in
Surgical Robotics: Embracing Multimodal Imaging Guidance, Intelligence, and
Bio-inspired Mechanisms
Domain Adaptive Sim-to-Real Segmentation of Oropharyngeal Organs
Video-assisted transoral tracheal intubation (TI) necessitates using an
endoscope that helps the physician insert a tracheal tube into the glottis
instead of the esophagus. The growing trend of robotic-assisted TI would
require a medical robot to distinguish anatomical features like an experienced
physician which can be imitated by utilizing supervised deep-learning
techniques. However, the real datasets of oropharyngeal organs are often
inaccessible due to limited open-source data and patient privacy. In this work,
we propose a domain adaptive Sim-to-Real framework called IoU-Ranking
Blend-ArtFlow (IRB-AF) for image segmentation of oropharyngeal organs. The
framework includes an image blending strategy called IoU-Ranking Blend (IRB)
and style-transfer method ArtFlow. Here, IRB alleviates the problem of poor
segmentation performance caused by significant datasets domain differences;
while ArtFlow is introduced to reduce the discrepancies between datasets
further. A virtual oropharynx image dataset generated by the SOFA framework is
used as the learning subject for semantic segmentation to deal with the limited
availability of actual endoscopic images. We adapted IRB-AF with the
state-of-the-art domain adaptive segmentation models. The results demonstrate
the superior performance of our approach in further improving the segmentation
accuracy and training stability.Comment: The manuscript is accepted by Medical & Biological Engineering &
Computing. Code and dataset:
https://github.com/gkw0010/EISOST-Sim2Real-Dataset-Releas
First-principles study of ground state properties and high pressure behavior of ThO2
The mechanical properties, electronic structure and phonon dispersion of
ground state ThO as well as the structure behavior up to 240 GPa are
studied by using first-principles density-functional theory. Our calculated
elastic constants indicate that both the ground state fluorite structure and
high pressure cotunnite structure of ThO are mechanically stable. The
bulk modulus, shear modulus, and Young's modulus of cotunnite ThO are all
smaller by approximately 25% compared with those of fluorite ThO. The
Poisson's ratios of both structures are approximately equal to 0.3 and the
hardness of fluorite ThO is 27.33 GPa. The electronic structure and
bonding nature of fluorite ThO are fully analyzed, which show that the
Th-O bond displays a mixed ionic/covalent character. The valence of Th and O
ions in fluorite ThO can be represented as Th and
O. The phase transition from the fluorite to cotunnite structure is
calculated to be at the pressure of 26.5 GPa, consistent with recent
experimental measurement by Idiri \emph{et al}. \cite{Idiri}. For the cotunnite
phase it is further predicted that an isostructural transition takes place in
the pressure region of 80 to 130 GPa.Comment: 9 pages, 10 figure
Biodiversity and phylogenetic analysis of the gut microbiome of Euphausia superba Dana from the Rose Sea of the Antarctic Ocean
Metabolites derived from marine symbiotic microorganisms have great potential as lead compounds for the discovery of novel marine drugs. Euphausia superba Dana, which lives in the Antarctic Ocean, is regarded as a new source of marine microbial natural products. However, no studies have examined the biodiversity of the symbiotic intestinal microbiome of E. superba. To address this issue, the species diversity and abundance of the gut microbiome of E. superba Dana from the Rose Sea of the Antarctic Ocean were analyzed by culture-independent high-throughput sequencing and pure culture methods. A comparison with gene databases revealed that the microbiome contained 61 known microbial species and a plethora of uncultivable microorganisms. Additionally, 7% of the species in the microbiome were currently unknown. The microbes belonged to 56 genera, eight of which, including Arthrobacter, Bacillus, Candidatus, Lactococcus, Lysinibacillus, Leuconostoc, Solibacillus, and Vibrio, were dominant, as were Vibrionaceae spp. Moreover, 81 microbial strains were isolated by the pure culture method, and they belonged to 36 genera, including Mobilicoccus, Rhodococcus, Arthrobacter, and Microbacterium. The results obtained by two different methods demonstrate the richness of the microbial biodiversity of the gut microbiome of E. superba, and it also suggests that they have good potential for the discovery of novel marine microbial species
Complete Genome Sequence and Characterization of a Protein-Glutaminase Producing Strain, Chryseobacterium proteolyticum QSH1265
Recently, an enzyme named protein-glutaminase (PG) has been identified as a new type of enzyme with significant potential for deamidation of food proteins. The enzyme is shown to be expressed as a pre-pro-protein with a putative signal peptide of 21 amino acids, a pro-sequence of 114 amino acids, and a mature PG of 185 amino acids. The microbial enzyme PG specifically catalyzes deamidation of proteins without protein hydrolysis pretreatment and only reacts with glutamine residues in the side-chains of proteins or long peptides. All these attributes suggest that it has a great potential for food industrial applications. However, until recently, there have been relatively few studies of the PG-producing strains. A strain named Chryseobacterium proteolyticum QSH1265 which can produce PG was isolated from a soil sample collected in Songjiang, Shanghai, China. Its enzyme activity was about 0.34 ± 0.01 U/mL when using carboxybenzoxy-Gln-Gly as a substrate. The strain can produce acid from D-glucose, maltose, L-arabinose sucrose, glycerol, and mannitol but not fructose, and it is also positive for indole production and urease. Here we describe the complete genome sequence of this strain via PacBio RSII sequencing. The C. proteolyticum QSH1265 genome consists of a circular chromosome with total length of 4,849,803 bp without any plasmids. All of 4563 genes were predicted including 4459 genes for protein-coding and 104 RNA-relative genes with an average G+C content of 36.16%. The KEGG and COG annotation provide information for the specific function of proteins encoded in the genome, such as proteases, chromoproteins, stress proteins, antiporters, etc. A highly conserved hypothetical protein shares a promoter with the gene encoding the protein-glutaminase enzyme. The genome sequence and preliminary annotation provide valuable genetic information for further study of C. proteolyticum
Atomic Layer Deposition of Buffer Layers for the Growth of Vertically Aligned Carbon Nanotube Arrays
Vertically aligned carbon nanotube arrays (VACNTs) show a great potential for various applications, such as thermal interface materials (TIMs). Besides the thermally oxidized SiO 2 , atomic layer deposition (ALD) was also used to synthesize oxide buffer layers before the deposition of the catalyst, such as Al 2 O 3 , TiO 2 , and ZnO. The growth of VACNTs was found to be largely dependent on different oxide buffer layers, which generally prevented the diffusion of the catalyst into the substrate. Among them, the thickest and densest VACNTs could be achieved on Al 2 O 3 , and carbon nanotubes were mostly triple-walled. Besides, the deposition temperature was critical to the growth of VACNTs on Al 2 O 3 , and their growth rate obviously reduced above 650 \ub0C, which might be related to the Ostwald ripening of the catalyst nanoparticles or subsurface diffusion of the catalyst. Furthermore, the VACNTs/graphene composite film was prepared as the thermal interface material. The VACNTs and graphene were proved to be the effective vertical and transverse heat transfer pathways in it, respectively
Molecular detection reveals diverse tick-borne bacterial and protozoan pathogens in two tick species from Yingshan County of Hubei Province, China in 2021–2022
In this study, a total of 179 ticks infesting ruminant livestock, including 166 Haemaphysalis longicornis ticks and 13 Rhipicephalus microplus ticks were collected from Yingshan county of Hubei province, China in 2021–2022. PCR testing and sequence analysis revealed that the ticks infected with various species of pathogens including Rickettsia (R. japonica), Anaplasma (A. bovis, A. ovis, A. platys, and Ca. A. boleense), Ehrlichia (E. minasensis and Ehrlichia sp.), Theileria (T. orientalis and T. luwenshuni), and Babesia (B. bigemina). The infection rates of these pathogens were 0.56, 16.76, 7.26, 2.79 and 0.56%. respectively, while only 3 of 13 R. microplus ticks were detected to be infected wth Ehrlichia sp., A. bove., or T. luwenshuni. Our results revealed that a variety of tick-borne pathogens highly carried by these ticks, specially Ha. longicornis. Therefore, it is necessary to make effective control of the ticks and the tick-borne diseases in the County
Phase II of the LAMOST-Kepler/K2 survey. I. Time series of medium-resolution spectroscopic observations
Phase \RNum{2} of the LAMOST-{\sl Kepler/K}2 survey (LK-MRS), initiated in
2018, aims at collecting medium-resolution spectra (; hereafter
MRS) for more than stars with multiple visits ( epochs) over a
period of 5 years (2018 September to 2023 June). We selected 20 footprints
distributed across the {\sl Kepler} field and six {\sl K}2 campaigns, with each
plate containing a number of stars ranging from to .
During the first year of observations, the LK-MRS has already collected
and high-quality spectra in the blue and red
wavelength range, respectively. The atmospheric parameters and radial
velocities for spectra of targets were successfully
calculated by the LASP pipeline. The internal uncertainties for the effective
temperature, surface gravity, metallicity, and radial velocity are found to be
\,K, \,dex, \,dex, and \,km\,s, respectively. We
found , , and stars in common with the targets from the
LAMOST low-resolution survey (LRS), GAIA and APOGEE, respectively,
corresponding to a fraction of , and . In
general, the parameters derived from LK-MRS spectra are consistent with those
obtained from the LRS and APOGEE spectra, but the scatter increases as the
surface gravity decreases when comparing with the measurements from APOGEE. A
large discrepancy is found with the GAIA values of the effective temperature.
The comparisons of radial velocities of LK-MRS to GAIA and LK-MRS to APOGEE
nearly follow an Gaussian distribution with a mean and
\,km\,s, respectively.Comment: 24 pages, 15 figures, 4 tables, ApJS, accepte
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