Adaptive locomotion of artificial microswimmers

Bacteria can exploit mechanics to display remarkable plasticity in response to locally changing physical and chemical conditions. Compliant structures play a striking role in their taxis behavior, specifically for navigation inside complex and structured environments. Bioinspired mechanisms with rationally designed architectures capable of large, nonlinear deformation present opportunities for introducing autonomy into engineered small-scale devices. This work analyzes the effect of hydrodynamic forces and rheology of local surroundings on swimming at low Reynolds number, identifies the challenges and benefits of utilizing elastohydrodynamic coupling in locomotion, and further develops a suite of machinery for building untethered microrobots with self-regulated mobility. We demonstrate that coupling the structural and magnetic properties of artificial microswimmers with the dynamic properties of the fluid leads to adaptive locomotion in the absence of on-board sensors

Anomalous phase transition of layered lepidocrocite titania nanosheets to anatase and rutile

In this study, phase transformations from lepidocrocite titania (L-TiO2) nanosheets to rutile (R-TiO2) and anatase (A-TiO2) have been systematically investigated as a function of the preparation conditions, such as pH and freeze-drying, and as a function of the temperature treatment. We have found that the transformation of (L-TiO2) into rutile takes place upon freeze-drying treatment. We report that temperature determined the final phase structure in the transition phase of the L-TiO2 nanosheets into TiO2 nanoparticles, while the pH determined the final morphology and particle size. On the basis of the experimental results, two different transition pathways of dissolution–recrystallization and topologically rolling transition have been proposed. Our results give a full map of phase transition and morphology evolution of L-TiO2 to R-TiO2/A-TiO2 that can provide guideline to new materials design, especially for photocatalysts

Vibration analysis of marine propulsion shafting by the coupled finite element method

Marine propulsion shafting connects the main engine and propeller, and plays an important role in promoting the movement of ships. Along with the operation of shafting system, various vibration forms couple with each other and cause different kinds of coupled vibrations, which seriously threaten the safety and reliability of ships. In this paper, a finite element model of marine propulsion shafting is established with coupled constraint on the elements of propeller, and the coupled torsional and transverse vibration under idling and loading conditions are studied at different rotational speeds. According to comparison of numerical simulation results and experimental tests, the coupled finite element method can reveal the basic principles of coupled dynamics of marine propulsion shafting and provide good technical support for predicting the coupled vibration, thus improving the safety and reliability of sailing performance of the ships

CT and MRI Imaging Features and Grades of Liver Iron Deposition

CT and MRI imaging features and grades of liver iron deposition（LID）were discussed and evaluated in clinical application.The imaging and laboratory data of 20 patients with LID were analyzed retrospectively. CT value of liver were measured and MR signal intensity ratio of muscle/liver calculated.A new imaging grade of LID were made with CT and MR, and the grade correlation was analyzed between CT, MR and SF. All of 20 patients with LID, 19 cases were CT examination, their CT value ranging of liver were from 55HU to 116HU, of which more than 72HU were in 7 cases and 72HU or less in 12. 14 cases were MR examination with the low signal of liver, and the inverse phase signal of T1WI was higher than that of the positive phase. There were no significant difference among the grade of CT, T1WI, T2WI and SF (P>0.05), and there were the positive correlation of grade between CT, T1WI, T2WI and SF (rs=0.803,0.847,0.677 respectively), and of values between CT, T1WI SIR, T2WI SIR and SF(rs=0.454, 0.538, 0.811 respectively). CT can show the LID with high-density, but the mild LID can be with normal density, which is the false negative. MRI can show LID with low-signal, of which T2WI is the lower than T1WI, it is beneficial to diagnose the early LID. Grades of CT and MR have good consistent with that of SF, and can reflect the severity of LID, particularly that of MR-T1WI grading

TCM-SD: A Benchmark for Probing Syndrome Differentiation via Natural Language Processing

Traditional Chinese Medicine (TCM) is a natural, safe, and effective therapy that has spread and been applied worldwide. The unique TCM diagnosis and treatment system requires a comprehensive analysis of a patient's symptoms hidden in the clinical record written in free text. Prior studies have shown that this system can be informationized and intelligentized with the aid of artificial intelligence (AI) technology, such as natural language processing (NLP). However, existing datasets are not of sufficient quality nor quantity to support the further development of data-driven AI technology in TCM. Therefore, in this paper, we focus on the core task of the TCM diagnosis and treatment system -- syndrome differentiation (SD) -- and we introduce the first public large-scale dataset for SD, called TCM-SD. Our dataset contains 54,152 real-world clinical records covering 148 syndromes. Furthermore, we collect a large-scale unlabelled textual corpus in the field of TCM and propose a domain-specific pre-trained language model, called ZY-BERT. We conducted experiments using deep neural networks to establish a strong performance baseline, reveal various challenges in SD, and prove the potential of domain-specific pre-trained language model. Our study and analysis reveal opportunities for incorporating computer science and linguistics knowledge to explore the empirical validity of TCM theories.Comment: 10 main pages + 2 reference pages, to appear at CCL202

New advances in catalysts for polystyrene hydrogenation

Polystyrene is one of the most widely used plastics, and could be catalytic hydrogenated to polycyclohexylethylene with improved physical properties. The research progress in the efficiency palladium catalyst for polystyrene hydrogenation was illustrated and reviewed, further development was discussed

Experimental Verification of Gene Expression Related to Lung Cancer in Nasal Epitthelia

Genes expression related to lung cancer are observed in nasal epitthelia, to identify their similarities and differences and provide the basis for possible application. There are three groups:non-lung cancer group (NLC), lung cancer group (LC) and postoperative lung cancer group (PLC).The genes expression in nasal epitthelia were observed by PCR, including the HCK, NCF1, TLR8, EMR3, CSF2RB, DYSF, SPEF2, ANKFN1, HYDIN, DNAH5, C12orf55 and CCDC113. Their expression levels were obtained and statistically compared. Results showed that all the related genes in LC and PLC groups were highly expressed. There are significant difference in HCK, NCF1, TLR8, EMR3, CSF2RB and C12orf55 gene expression between the LC or PLC and NLC, and in EMR3 and C12orf55 between LC and PLC. Conclusions are HCK, NCF1, TLR8, EMR3, CSF2RB, C12orf55 can be used for lung cancer screening, while EMR3 and C12orf55 for the review of post-operative lung cancer

New advances in catalysts for C9 petroleum resin hydrogenation

C9 petroleum resin is a thermoplastic polymer produced by polymerization of C9 fraction obtaining from the steam cracking unit, and could be catalytic hydrogenated to remove the ethylenic C=C bond, aromatic ring with improved physical properties. The research progress in the efficiency supported nickel or/and palladium catalysts for C9 petroleum resin hydrogenation was illustrated and reviewed, further development was discussed

Adaptive locomotion of artificial microswimmers.

Bacteria can exploit mechanics to display remarkable plasticity in response to locally changing physical and chemical conditions. Compliant structures play a notable role in their taxis behavior, specifically for navigation inside complex and structured environments. Bioinspired mechanisms with rationally designed architectures capable of large, nonlinear deformation present opportunities for introducing autonomy into engineered small-scale devices. This work analyzes the effect of hydrodynamic forces and rheology of local surroundings on swimming at low Reynolds number, identifies the challenges and benefits of using elastohydrodynamic coupling in locomotion, and further develops a suite of machinery for building untethered microrobots with self-regulated mobility. We demonstrate that coupling the structural and magnetic properties of artificial microswimmers with the dynamic properties of the fluid leads to adaptive locomotion in the absence of on-board sensors.ER

Psoralen-loaded lipid-polymer hybrid nanoparticles enhance doxorubicin efficacy in multidrug-resistant HepG2 cells

Background: Psoralen (PSO), a major active component of Psoralea corylifolia, has been shown to overcome multidrug resistance in cancer. A drug carrier comprising a lipid-monolayer shell and a biodegradable polymer core for sustained delivery and improved efficacy of drug have exhibited great potential in efficient treatment of cancers. Methods: The PSO-loaded lipid polymer hybrid nanoparticles were prepared and characterized. In vitro cytotoxicity assay, cellular uptake, cell cycle analysis, detection of ROS level and mitochondrial membrane potential (ΔΨm) and western blot were performed. Results: The P-LPNs enhanced the cytotoxicity of doxorubicin (DOX) 17-fold compared to free DOX in multidrug resistant HepG2/ADR cells. Moreover, P-LPNs displayed pro-apoptotic activity, increased levels of ROS and depolarization of ΔΨm. In addition, there were no significant effects on cellular uptake of DOX, cell cycle arrest, or the expression of P-glycoprotein. Mechanistic studies suggested that P-LPNs enhanced DOX cytotoxicity by increased release of cytochrome c and enhanced caspase3 cleavage, causing apoptosis in HepG2/ADR cells. Conclusion: The lipid-polymer hybrid nanoparticles can be considered a powerful and promising drug delivery system for effective cancer chemotherapy. Keywords: lipid-polymer hybrid nanoparticles, psoralen, drug delivery, HepG2, ADR cells, apoptosis.This work was supported by the National Natural Science Foundation of China (81273707), the Ministry of Education in the New Century Excellent Talents (NECT-12-0677), the Natural Science Foundation of Guangdong (S2013010012880, 2016A030311037), the Science and Technology Program of Guangzhou (2014J4500005, 201704030141), the Science Program of the Department of Education of Guangdong (2013KJCX0021, 2015KGJHZ012), the Science and Technology Program of Guangdong (2015A050502027), and the Special Project of International Scientific and Technological Cooperation in Guangzhou Development District (2017GH16)