On a hierarchical control strategy for multi-agent formation without reflection

This paper considers a formation shape control problem for point agents in a two-dimensional ambient space, where the control is distributed, is based on achieving desired distances between nominated agent pairs, and avoids the possibility of reflection ambiguities. This has potential applications for large-scale multi-agent systems having simple information exchange structure. One solution to this type of problem, applicable to formations with just three or four agents, was recently given by considering a potential function which consists of both distance error and signed triangle area terms. However, it seems to be challenging to apply it to formations with more than four agents. This paper shows a hierarchical control strategy which can be applicable to any number of agents based on the above type of potential function and a formation shaping incorporating a grouping of equilateral triangles, so that all controlled distances are in fact the same. A key analytical result and some numerical results are shown to demonstrate the effectiveness of the proposed method.Comment: Accepted by the 57th IEEE Conference on Decision and Contro

Optimal dispatch based on prediction of distributed electric heating storages in combined electricity and heat networks

The volatility of wind power generations could significantly challenge the economic and secure operation of combined electricity and heat networks. To tackle this challenge, this paper proposes a framework of optimal dispatch with distributed electric heating storage based on a correlation-based long short-term memory prediction model. The prediction model of distributed electric heating storage is developed to model its behavior characteristics which are obtained by the autocorrelation and correlation analysis with external factors including weather and time-of-use price. An optimal dispatch model of combined electricity and heat networks is then formulated and resolved by a constraint reduction technique with clustering and classification. Our method is verified through numerous simulations. The results show that, compared with the state-of-the-art techniques of support vector machine and recurrent neural networks, the mean absolute percentage error with the proposed correlation-based long short-term memory can be reduced by 1.009 and 0.481 respectively. Compared with conventional method, the peak wind power curtailment with dispatching distributed electric heating storage is reduced by nearly 30% and 50% in two cases respectively

A Protective Role by Interleukin-17F in Colon Tumorigenesis

Interleukin-17F (IL-17F), produced by Th17 cells and other immune cells, is a member of IL-17 cytokine family with highest homology to IL-17A. IL-17F has been shown to have multiple functions in inflammatory responses. While IL-17A plays important roles in cancer development, the function of IL-17F in tumorigenesis has not yet been elucidated. In the current study, we found that IL-17F is expressed in normal human colonic epithelial cells, but this expression is greatly decreased in colon cancer tissues. To examine the roles of IL-17F in colon cancer, we have used IL-17F over-expressing colon cancer cell lines and IL-17F-deficient mice. Our data showed decreased tumor growth of IL-17F-transfected HCT116 cells comparing to mock transfectants when transplanted in nude mice. Conversely, there were increased colonic tumor numbers and tumor areas in Il-17f−/− mice than those from wild-type controls after colon cancer induction. These results indicate that IL-17F plays an inhibitory role in colon tumorigenesis in vivo. In IL-17F over-expressing tumors, there was no significant change in leukocyte infiltration; instead, we found decreased VEGF levels and CD31+ cells. While the VEGF levels were increased in the colon tissues of Il-17f−/− mice with colon cancer. Together, our findings demonstrate a protective role for IL-17F in colon cancer development, possibly via inhibiting tumor angiogenesis

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Zein nanoparticles as nontoxic delivery system for maytansine in the treatment of non-small cell lung cancer

Purpose Maytansine (DM1) is a potent anticancer drug and limited in clinical application due to its poor water solubility and toxic side effects. Zein is widely used in nano drug delivery systems due to its good biocompatibility. In this study, we prepared DM1-loaded zein nanoparticles (ZNPs) to achieve tumor targeting and reduce toxic side effects of DM1. Methods: ZNPs were prepared by phase separation and Box-Behnken design was used to optimize the formulation. Then, confocal fluorescence microscope and flow cytometry were used to determine cellular uptake of ZNPs. A549 cells were cultured in vitro to study cytotoxicity and used to establish tumor xenografts in nude mice. Biodistribution and antitumor activity of ZNPs were performed in vivo experiments. In addition, we also performed histological and immunohistochemical examinations on tumors and viscera. Results: The optimal prescription was obtained by using 120 μL zein added to 2 mL water under stirring in 300 rpm. The encapsulation efficiency and drug loading were 82.97 ± 0.80% and 3.32 ± 0.03%, respectively. We found that DM1-loaded ZNPs have a strong inhibitory effect on A549 cells, which stemmed from the ability of ZNPs to enhance cellular uptake. Furthermore, we demonstrated that DM1-loaded ZNPs exhibits a better antitumor efficacy than DM1, which tumor inhibition rate were 97.3% and 92.7%, respectively. The biodistribution revealed that ZNPs could targeted to tumor. Finally, we confirmed by histological that DM1-loaded ZNPs are nontoxic. Conclusion: DM1-loaded ZNPs have considerable antitumor activity. Thus, DM1-loaded ZNPs are a promising treatment of non-small cell lung cancer

R-loopBase: a knowledgebase for genome-wide R-loop formation and regulation.

R-loops play versatile roles in many physiological and pathological processes, and are of great interest to scientists in multiple fields. However, controversy about their genomic localization and incomplete understanding of their regulatory network raise great challenges for R-loop research. Here, we present R-loopBase (https://rloopbase.nju.edu.cn) to tackle these pressing issues by systematic integration of genomics and literature data. First, based on 107 high-quality genome-wide R-loop mapping datasets generated by 11 different technologies, we present a reference set of human R-loop zones for high-confidence R-loop localization, and spot conservative genomic features associated with R-loop formation. Second, through literature mining and multi-omics analyses, we curate the most comprehensive list of R-loop regulatory proteins and their targeted R-loops in multiple species to date. These efforts help reveal a global regulatory network of R-loop dynamics and its potential links to the development of cancers and neurological diseases. Finally, we integrate billions of functional genomic annotations, and develop interactive interfaces to search, visualize, download and analyze R-loops and R-loop regulators in a well-annotated genomic context. R-loopBase allows all users, including those with little bioinformatics background to utilize these data for their own research. We anticipate R-loopBase will become a one-stop resource for the R-loop community

Mn-Doped M₂CdCl₄ (M = CH₃NH₃⁺, C₂H₈N⁺, and C₃H₁₀N⁺) Layered Hybrid Perovskite and Its Flexible Film Based on Simple Mechanochemical Synthesis

Layered hybrid perovskites show significant advantages in the field of optoelectronics. However, the low quantum efficiency and complex preparation methods limit their applications. In this work, we developed a series of perovskite powders with a two-dimensional (2D) layered structure of organic–inorganic hybrid metal halides M2CdCl4:x%Mn (M = CH3NH3+, C2H8N+, C3H10N+) via facile mechanochemical methods. The prepared manganese Mn-doped MA2CdCl4 produces orange emission at 605 nm under both 254 and 420 nm excitation, which originates from a dual excitation channel competition mechanism, and its excitation channel could be changed with the increase of Mn2+ ion concentration. Typically, MA2CdCl4:20%Mn powder exhibits high photoluminescence quantum yield (PLQY) close to 90% at 605 nm due to the organic amine ions enlarging the Mn–Mn interlayer distances. In addition, we prepared MA2CdCl4:x%Mn@PVA flexible films, which also exhibit good luminescence at 254 nm excitation and were unexpectedly found to have a better response to Cs+, which could be a candidate for anticounterfeiting applications

Surface interaction between metazeunerite and an indigenous microorganism Kocuria rosea: Implications for bioremediation of As-U tailings

© 2018 Elsevier B.V. Metazeunerite (Cu(UO2)2(AsO4)2·8H2O), a highly water-insoluble mineral, is shown to be an important solubility limiting phase controlling uranium and arsenic migration. This mineral has been identified in the shallow vadose zone of contaminated area at a closed uranium mine in the southwest of China. Consequently, modeling the evolution of U and As in vadose zone driven by indigenous microorganisms requires accurate knowledge of the mineral-microbe interaction process. In the present contribution, the surface interaction between metazeunerite and an indigenous bacteria Kocuria rosea was characterized by flow-cell ATR-FTIR spectroscopy, CLSM, SEM-EDS, XPS, and first-principle calculation. Results suggested that Kocuria rosea cells attached on the surface of metazeunerite and formed biofilm gradually through P[dbnd]O, C[dbnd]O, and COO– groups on the cells membrane in real time. Metazeunerite was eroded by the adhered Kocuria rosea cells layer by layer, whose surface functional groups could structurally couple to the metals on metazeunerite surface and eventually form multi-dentate complexes. Furthermore, As(V), located in the mineral lattice of metazeunerite, was transformed to As(III) by Kocuria rosea after 24 h while U(VI) was not reduced and did not result in lattice structure destruction and reductive dissolution. The results of the study will help to design long-term effectiveness of bioremediation strategies of As-U contamination

Additional file 1 of Vitrectomy with sulfur hexafluoride versus air tamponade for idiopathic macular hole: a retrospective study

Supplementary Material