134 research outputs found
DeepICP: An End-to-End Deep Neural Network for 3D Point Cloud Registration
We present DeepICP - a novel end-to-end learning-based 3D point cloud
registration framework that achieves comparable registration accuracy to prior
state-of-the-art geometric methods. Different from other keypoint based methods
where a RANSAC procedure is usually needed, we implement the use of various
deep neural network structures to establish an end-to-end trainable network.
Our keypoint detector is trained through this end-to-end structure and enables
the system to avoid the inference of dynamic objects, leverages the help of
sufficiently salient features on stationary objects, and as a result, achieves
high robustness. Rather than searching the corresponding points among existing
points, the key contribution is that we innovatively generate them based on
learned matching probabilities among a group of candidates, which can boost the
registration accuracy. Our loss function incorporates both the local similarity
and the global geometric constraints to ensure all above network designs can
converge towards the right direction. We comprehensively validate the
effectiveness of our approach using both the KITTI dataset and the
Apollo-SouthBay dataset. Results demonstrate that our method achieves
comparable or better performance than the state-of-the-art geometry-based
methods. Detailed ablation and visualization analysis are included to further
illustrate the behavior and insights of our network. The low registration error
and high robustness of our method makes it attractive for substantial
applications relying on the point cloud registration task.Comment: 10 pages, 6 figures, 3 tables, typos corrected, experimental results
updated, accepted by ICCV 201
MSC Transplantation Improves Osteopenia via Epigenetic Regulation of Notch Signaling in Lupus
Mesenchymal stem cell transplantation (MSCT) has been used to treat human diseases, but the detailed mechanisms underlying its success are not fully understood. Here we show that MSCT rescues bone marrow MSC (BMMSC) function and ameliorates osteopenia in Fas-deficient-MRL/lpr mice. Mechanistically, we show that Fas deficiency causes failure of miR-29b release, thereby elevating intracellular miR-29b levels, and downregulates DNA methyltransferase 1 (Dnmt1) expression in MRL/lpr BMMSCs. This results in hypomethylation of the Notch1 promoter and activation of Notch signaling, in turn leading to impaired osteogenic differentiation. Furthermore, we show that exosomes, secreted due to MSCT, transfer Fas to recipient MRL/lpr BMMSCs to reduce intracellular levels of miR-29b, which results in recovery of Dnmt1-mediated Notch1 promoter hypomethylation and thereby improves MRL/lpr BMMSC function. Collectively our findings unravel the means by which MSCT rescues MRL/lpr BMMSC function through reuse of donor exosome-provided Fas to regulate the miR-29b/Dnmt1/Notch epigenetic cascade
Role of oxidative stress in trichloroethylene-induced toxicity
Trichloroethylene (TCE) is a common industrial organic solvent and environmental contaminant. People are exposed to TCE through occupational contact or environmental pollution, which leads to serious human health hazards. A large number of studies have shown that oxidative stress plays an important role in the TCE-induced multi-target organ toxicity. However, the research of related signaling pathways remains to be deepened. In this review, we summarized the epidemiological, animal, and cellular studies correlated to liver toxicity, kidney toxicity, cardiac developmental toxicity, placental developmental toxicity, neurodevelopmental toxicity, and autoimmune response induced by TCE. In addition, the possible molecular mechanisms of oxidative stress in TCE-induced toxicity were concluded, including DNA damage, mitochondrial dysfunction, cell apoptosis, and abnormal activation of the immune system. Through literature review, we proposed that nuclear factor E2 related factor 2 may play an important role in mediating TCE-induced target organ toxicity, providing a theoretical basis for the prevention and treatment of adverse health effects caused by TCE
High-performance supercapacitors based on hierarchically porous carbons with a three-dimensional conductive network structure
Clews of polymer nanobelts (CsPNBs) have the advantages of inexpensive raw materials, simple synthesis and large output. Novel clews of carbon nanobelts (CsCNBs) have been successfully prepared by carbonizing CsPNBs and by KOH activation subsequently. From the optimized process, CsCNBs*4, with a specific surface area of 2291 m2 gâ1 and a pore volume of up to 1.29 cm3 gâ1, has been obtained. Fundamentally, the CsCNBs possess a three-dimensional conductive network structure, a hierarchically porous framework, and excellent hydrophilicity, which enable fast ion diffusion through channels and a large enough ion adsorption/desorption surface to improve electrochemical performance of supercapacitors. The product exhibits a high specific capacitance of 327.5 F gâ1 at a current density of 0.5 A gâ1 in a three-electrode system. The results also reveal a high-rate capacitance (72.2% capacitance retention at 500 mV sâ1) and stable cycling lifetime (95% of initial capacitance after 15â000 cycles). Moreover, CsCNBs*4 provides a high energy density of 29.8 W h kgâ1 at a power density of 345.4 W kgâ1 in 1 M tetraethylammonium tetrafluoroborate/acetonitrile (TEABF4/AN) electrolyte. These inspiring results imply that this carbon material with a three-dimensional conductive network structure possesses excellent potential for energy storage
Ultrahigh-content nitrogen-decorated nanoporous carbon derived from metal organic frameworks and its application in supercapacitors
Single electric double-layer capacitors cannot meet the growing demand for energy due to their insufficient energy density. Generally speaking, the supercapacitors introduced with pseudo-capacitance by doping heteroatoms (N, O) in porous carbon materials can obtain much higher capacitance than electric double-layer capacitors. In view of above merits, in this study, nanoporous carbon materials with ultrahigh N enrichment (14.23âŻwt%) and high specific surface area (942âŻm2âŻgâ1)âŻby in situ introduction of N-doped MOF (ZTIF-1, Organic ligands 5-methyltetrazole/C2H4N4) were produced. It was found that as supercapacitors' electrode materials, these nanoporous carbons exhibit a capacitance as high as 272âŻFâŻg-1âŻat 0.1âŻAâŻgâ1, and an excellent cycle life (almost no attenuation after 10,000 cycles.). Moreover, the symmetric supercapacitors were assembled to further investigate the actual capacitive performance, and the capacitance shows up to 154âŻFâŻg-1âŻat 0.1âŻAâŻgâ1. Such excellent properties may be attributed to a combination of a high specific surface area, ultrahigh nitrogen content and hierarchically porous structure. The results shown in this study fully demonstrate that the nanoporous carbon materials containing ultrahigh nitrogen content can be used as a potential electrode material in supercapacitors
Facile synthesis of ultrahigh-surface-area hollow carbon nanospheres and their application in lithium-sulfur batteries
Hollow carbon nanospheres (HCNs) with specific surface areas up to 2949â
m2âgâ1 and pore volume up to 2.9â
cm3âgâ1 were successfully synthesized from polyanilineâcoâpolypyrrole hollow nanospheres by carbonization and CO2 activation. The cavity diameter and wall thickness of HCNs can be easily controlled by activation time. Owing to their large inner cavity and enclosed structure, HCNs are desirable carriers for encapsulating sulfur. To better understand the effects of pore characteristics and sulfur contents on the performances of lithiumâsulfur batteries, three composites of HCNs and sulfur are prepared and studied in detail. The composites of HCNs with moderate specific surface areas and suitable sulfur content present a better performance. The first discharge capacity of this composite reaches 1401â
mAhâgâ1 at 0.2â
C. Even after 200â
cycles, the discharge capacity remains at 626â
mAhâgâ1
Urinary microbiota signatures associated with different types of urinary diversion: a comparative study
BackgroundRadical cystectomy and urinary diversion (UD) are gold standards for non-metastatic muscle-invasive bladder cancer. Orthotopic neobladder (or Studer), ileal conduit (or Bricker) and cutaneous ureterostomy (CU) are mainstream UD types. Little is known about urinary microbiological changes after UD. MethodsIn this study, urine samples were collected from healthy volunteers and patients with bladder cancer who had received aforementioned UD procedures. Microbiomes of samples were analyzed using 16S ribosomal RNA gene sequencing, and microbial diversities, distributions and functions were investigated and compared across groups. ResultsHighest urine microbial richness and diversity were observed in healthy controls, followed by Studer patients, especially those without hydronephrosis or residual urine, α-diversity indices of whom were remarkably higher than those of Bricker and CU groups. Studer UD type was the only independent factor favoring urine microbial diversity. The urine microflora structure of the Studer group was most similar to that of the healthy individuals while that of the CU group was least similar. Studer patients and healthy volunteers shared many similar urine microbial functions, while Bricker and CU groups exhibited opposite characteristics. ConclusionOur study first presented urinary microbial landscapes of UD patients and demonstrated the microbiological advantage of orthotopic neobladder. Microbiota might be a potential tool for optimization of UD management
Diploid mycelia of Ustilago esculenta fails to maintain sustainable proliferation in host plant
Smut fungi display a uniform life cycle including two phases: a saprophytic phase in vitro and a parasitic phase in host plants. Several apathogenic smut fungi are found, lacking suitable hosts in their habitat. Interestingly, MT-type Ustilago esculenta was found to maintain a parasitic life, lacking the saprophytic phase. Its long period of asexual proliferation in plant tissue results in severe defects in certain functions. In this study, the growth dynamics of U. esculenta in plant tissues were carefully observed. The mycelia of T- and MT-type U. esculenta exhibit rapid growth after karyogamy and aggregate between cells. While T-type U. esculenta successfully forms teliospores after aggregation, the aggregated mycelia of MT-type U. esculenta gradually disappeared after a short period of massive proliferation. It may be resulted by the lack of nutrition such as glucose and sucrose. After overwintering, infected Zizania latifolia plants no longer contained diploid mycelia resulting from karyogamy. This indicated that diploid mycelia failed to survive in plant tissues. It seems that diploid mycelium only serves to generate teliospores. Notably, MT-type U. esculenta keeps the normal function of karyogamy, though it is not necessary for its asexual life in plant tissue. Further investigations are required to uncover the underlying mechanism, which would improve our understanding of the life cycle of smut fungi and help the breeding of Z. latifolia
CoSe2/Co nanoheteroparticles embedded in Co, Nco-doped carbon nanopolyhedra/nanotubes as anefficient oxygen bifunctional electrocatalyst for Znâair batteries
Transition metal selenide-based materials have been demonstrated as promising electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), yet the actual design of a highly efficient and stable electro-catalyst based on these materials still remains a long and arduous challenge. Herein, a predesigned hybrid Zn/Co zeolitic imidazole framework was used to fabricate CoSe2/Co nanoheteroparticles embedded within hierarchically porous Co, N co-doped carbonnanopolyhedra/nanotubes (CoSe2/Co@NC-CNTs) through a facile approach involving controlled carbonization and selenization procedures. As expected, the optimized CoSe2/Co@NC-CNT-1 displayed outstanding electrocatalytic performance for the ORR and OER, with an onset potential of 0.95 V vs. RHE, a half-wave potential of 0.84 V vs. RHE for ORR, and a potential of 1.69 V vs. RHE for OER at 10 mA cmâ2. It also exhibited excellent long-term stability and methanol resistance ability, which were superior to commercial IrO2 and the commercial 20 wt% Pt/C catalyst. Notably, the assembled Znâair battery with CoSe2/Co@NC-CNT-1 showed a low chargeâdischarge voltage gap (0.696 V at 10 mA cmâ2) and a high peak power density (100.28 mW cmâ2) with long-term cycling stability. These superior performances can be ascribed to the synergistic effects of the highly active CoSe2/Co nanoheterostructure, hierarchically porous structure with a large surface area, high electrical conductivity and uniform doping of the Co and
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