174 research outputs found
Fine-grained Text and Image Guided Point Cloud Completion with CLIP Model
This paper focuses on the recently popular task of point cloud completion
guided by multimodal information. Although existing methods have achieved
excellent performance by fusing auxiliary images, there are still some
deficiencies, including the poor generalization ability of the model and
insufficient fine-grained semantic information for extracted features. In this
work, we propose a novel multimodal fusion network for point cloud completion,
which can simultaneously fuse visual and textual information to predict the
semantic and geometric characteristics of incomplete shapes effectively.
Specifically, to overcome the lack of prior information caused by the
small-scale dataset, we employ a pre-trained vision-language model that is
trained with a large amount of image-text pairs. Therefore, the textual and
visual encoders of this large-scale model have stronger generalization ability.
Then, we propose a multi-stage feature fusion strategy to fuse the textual and
visual features into the backbone network progressively. Meanwhile, to further
explore the effectiveness of fine-grained text descriptions for point cloud
completion, we also build a text corpus with fine-grained descriptions, which
can provide richer geometric details for 3D shapes. The rich text descriptions
can be used for training and evaluating our network. Extensive quantitative and
qualitative experiments demonstrate the superior performance of our method
compared to state-of-the-art point cloud completion networks
New Reassortant H5N6 Highly Pathogenic Avian Influenza Viruses in Southern China, 2014
New reassortant H5N6 highly pathogenic avian influenza viruses were isolated from apparently healthy domestic ducks in Southern China in 2014. Our results show that the viruses grew efficiently in eggs and replicated systemically in chickens. They were completely lethal in chicken (100% mortality), and the mean death time (MDT) was 6 to 7 days post-inoculation (DPI). The viruses could transmit in chickens by naïve contact. BLAST analysis revealed that their HA gene was most closely related to A/wild duck/Shangdong/628/2011 (H5N1), and their NA genes were most closely related to A/swine/Guangdong/K6/2010 (H6N6). The other genes had the highest identity with A/wild duck/Fujian/1/2011(H5N1). The results of phylogenetic analysis showed that their HA genes clustered into clade 2.3.4.4 of the H5N1 viruses and all genes derived from H5 were Mix-like or H6-like viruses. Thus, the new H5N6 viruses were reassortanted of H5N1 and H6N6 virus. Therefore, the circulation of the new H5N6 avian influenza viruses may become a threat to poultry and human health
GASZ promotes germ cell derivation from embryonic stem cells
AbstractPrimordial germ cells (PGCs) are the first germ-line population that forms from the proximal epiblast of the developing embryo. Despite their biological importance, the regulatory networks whereby PGCs arise, migrate, and differentiate into gametes during embryonic development remains elusive, largely due to the limited number of germ cells in the early embryo. To elucidate the molecular mechanisms that govern early germ cell development, we utilized an in vitro differentiation model of embryonic stem cells (ESCs) and screened a series of candidate genes with specific expression in the adult reproductive organs. We discovered that gain of function of Gasz, a gene previously reported to participate in meiosis of postnatal spermatocytes, led to the most robust upregulation of PGC formation from both human and murine ESCs. In contrast, Gasz deficiency resulted in pronounced reduction of germ cells during ESC differentiation and decreased expression of MVH and DAZL in genital ridges during early embryonic development. Further analyses demonstrated that GASZ interacted with DAZL, a key germ cell regulator, to synergistically promote germ cell derivation from ESCs. Thus, our data reveal a potential role of GASZ during embryonic germ cell development and provide a powerful in vitro system for dissecting the molecular pathways in early germ cell formation during embryogenesis
Increased p38-MAPK is responsible for chemotherapy resistance in human gastric cancer cells
<p>Abstract</p> <p>Background</p> <p>Chemoresistance is one of the main obstacles to successful cancer therapy and is frequently associated with Multidrug resistance (MDR). Many different mechanisms have been suggested to explain the development of an MDR phenotype in cancer cells. One of the most studied mechanisms is the overexpression of P-glycoprotein (P-gp), which is a product of the <it>MDR1 </it>gene. Tumor cells often acquire the drug-resistance phenotype due to upregulation of the <it>MDR1 </it>gene. Overexpression of <it>MDR1 </it>gene has often been reported in primary gastric adenocarcinoma.</p> <p>Methods</p> <p>This study investigated the role of p38-MAPK signal pathway in vincristine-resistant SGC7901/VCR cells. P-gp and MDR1 RNA were detected by Western blot analysis and RT-PCR amplification. Mitgen-activated protein kinases and function of P-gp were demonstrated by Western blot and FACS Aria cytometer analysis. Ap-1 activity and cell apoptosis were detected by Dual-Luciferase Reporter Assay and annexin V-PI dual staining.</p> <p>Results</p> <p>The vincristine-resistant SGC7901/VCR cells with increased expression of the multidrug-resistance 1 (<it>MDR1</it>) gene were resistant to P-gp-related drug and P-gp-unrelated drugs. Constitutive increases of phosphorylated p38-MAPK and AP-1 activities were also found in the drug-resistant cells. Inhibition of p38-MAPK by SB202190 reduced activator protein-1 (AP-1) activity and <it>MDR1 </it>expression levels and increased the sensitivity of SGC7901/VCR cells to chemotherapy.</p> <p>Conclusion</p> <p>Activation of the p38-MAPK pathway might be responsible for the modulation of P-glycoprotein-mediated and P-glycoprotein-unmediated multidrug resistance in the SGC7901/VCR cell line.</p
The effect of smear layer removal on E faecalis leakage and bond strength of four resin-based root canal sealers
Background: The aim of the study was to assess bacterial sealability and bonding ability of methacrylate-based Resilon (RS, SybronEndo), Endo Rez (ER, Ultradent Products Inc), and epoxy-based AH Plus (AH, Dentsply/DeTrey), MTA Fill Apex (MTAF, Angelus Solucoes Odontologicas) root canal sealers, and the effect of the smear layer removal on the sealability.Methods: One hundred thirty root segments were instrumented up to apical size #60 and rinsed with 2.5% NaOCl. Half of the roots were rinsed with 5ml 17% EDTA to remove the smear layer. All the roots were filled with AH, ER, MTAF sealers and gutta-percha, or RS with Resilon cones. After storage at 37 degrees C for 7 days the samples were mounted into bacterial leakage assay for 50 days.Another 100 roots were instrumented and rinsed as described above, split longitudinally, cut into the cervical, middle and apical parts. The sealers were injected through the plastic mould on the dentin surface. After 7 days of incubation at 37 degrees C, bond strength was tested using a notched-edge test fixture (Crosshead, Ultradent Products Inc.) and a universal testing machine (Lloyd Instruments).Results: AH revealed the longest mean time for bacterial resistance by 29.4 and 36.8 days (with and without smear layer, respectively) followed by RS (15.1 and 24.7 days, respectively). The difference between materials was significant (pBond strength values ranged from 0.2 0.1 to 3.5 +/- 0.7 MPa and increased from the apical to the cervical third. In the apical third, AH showed the highest mean (SD) bond values 1.4 (0.4) MPa and 1.7 (0.6) MPa (with and without smear, respectively, followed by RS, 0.5 (0.1) MPa and 0.8 (0.1) MPa, respectively. The difference between materials was significant (p=0.001).Conclusion: The effect of the smear layer removal on the sealability was material-dependent.</div
Co-Zeolitic Imidazolate Framework@Cellulose Aerogels from Sugarcane Bagasse for Activating Peroxymonosulfate to Degrade P-Nitrophenol
An efficient, green and reusable catalyst for organic pollutant wastewater treatment has been a subject of intense research in recent decades due to the limitation of current technologies. Cellulose based aerogel composites are considered to be an especially promising candidate for next-generation catalytic material. This project was conducted in order to evaluate the behavior and ability of green and reusable sugarcane bagasse aerogels to remove P-Nitrophesnol from waste-water aqueous. Co-Zeolitic imidazolate framework@ sugarcane bagasse aerogels composite catalysts were successfully prepared via simple in situ synthesis. The structure of hybrid aerogels and their efficient catalyst in peroxymonosulfate (PMS) activation for the degradation of p-nitrophenol (PNP) was investigated. As a result, the hybrid aerogels/PMS system removed 98.5% of PNP (10 mg/L) within 60~70 min, while the traditional water treatment technology could not achieve this. In addition, through a free radical capture experiment and electron paramagnetic resonance (EPR), the degradation mechanism of PNP was investigated. Further research found that the hybrid aerogels can effectively activate PMS to produce sulfate (SO∙ −4) and hydroxyl (OH∙ ). Both of them contributed to the degradation of PNP, and SO∙ −4 plays a crucial role in the degradative process. The most important feature of hybrid aerogels can be easily separated from the solution. The obtained results showed that the outer coating structure of cellulose can stabilize Co-ZIF and reduce the dissolution of cobalt ions under complex reaction conditions. Moreover, the prepared hybrid aerogels exhibit excellent reusability and are environmentally friendly with efficient catalytic efficiency. This work provides a new strategy for bagasse applications and material reusability
Highly sensitive acetone sensor based on WO3 nanosheets derived from WS2 nanoparticles with inorganic fullerene-like structures
Metal oxide semiconductor (MOS) gas sensors are promising for applications in environmental monitoring, dangerous gas detection, and disease diagnosis. Seeking for advanced MOS sensing materials that possess high sensitivity and low limit of detection (LOD) at sub-ppm level is a great challenge. Here, we report the first creation of two-dimensional (2D) WO3 nanosheets by annealing of the inorganic fullerene (IF)-like WS2 nanoparticles that were prepared via sulfurization of WO3 nanoparticles. Transformation of WS2 to WO3 was realised during the annealing process, simultaneously accompanied by the collapse of the hollow IF-WS2 structures and the formation of tiny 2D WO3 nanosheets with a lateral size of 40−80 nm. The resulting 2D WO3 nanosheets exhibited highly enhanced acetone-sensing performance in terms of sensitivity, selectivity, and response/recovery rates compared with the WO3 nanoparticles used as precursor for the synthesis of the IF-WS2 nanoparticles. The nanosheets also demonstrated great repeatability, reliable long-term stability, and very low LOD, making them a promising candidate as gas sensor to detect breath acetone
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