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Based on differential pulse voltammetry technology, we developed a portable and affordable instrument for on-site detection of trace heavy metal pollutants in liquid through a disposable plastic pipette. It mainly consists of a six-electrode electrochemical sensor which is integrated in the instrument. The pipette chip is equipped with a pump valve, and thus, it can avoid contamination. We have analyzed the sensitivity and specificity of the electrochemical sensor for heavy metal detection. Experimental results demonstrated that the limit of detection for Pb, Hg, Cu, and Zn was 2.2 ng/mL, 2.5 ng/mL, 15.5 ng/mL, and 10 ng/mL, respectively. The limit of quantification for them was 10 ng/mL, 25 ng/mL, 25 ng/mL, and 14 ng/mL, respectively. The correlation coefficient between peak current and the target heavy metal concentration was above 0.96. Finally, we have tested the analytical performance of the self-build instrument by measuring heavy metal ions in industrial wastewater and rainwater, respectively. Such an instrument is user-friendly for all users even for the common people, and we can envision its wide application in future heavy metal pollutant detection in groundwater, tap water, and supernatant of soil solution. [ABSTRACT FROM AUTHOR]

Time-varying formation control problem for a group of multiple quad-rotors has been considered in this article with the help of ellipsoid. Firstly, an elliptic equation with time-varying parameters has been firstly introduced to describe the desired formation patterns for multiple quad-rotors in three-dimensional space. Then position controller and attitude controller are constructed using the method of sliding model control, respectively. Through tuning parameters of the elliptic equation, time-varying formation control of multiple quad-rotors has been realized using the controllers proposed in this article where smoothing transition between rigid formations has been guaranteed. Simulation results for formation control of quad-rotors that perform translation, scaling, and rotating actions have illustrated effectiveness of the time-varying formation controller that proposed in this article. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Thermal ablation therapy has recently emerged as a promising noninvasive treatment modality for localized solid malignancies. Except its direct tumor‐cell‐killing effect on local tumor tissues, the immunomodulatory effect has also long been noticed which too has substantial effect on clinical outcome, but it is complicated. Though much has been investigated and rich evidences have been achieved, the fundamental state and profile of immunomodulation by thermal ablation in cancer patients, its exact mechanism, especially the systematic mechanism, and its effect on antitumor immunity remain unclear. Methods: In this study, we dynamically monitored the immunomodulation by thermal ablation through combined analysis of peripheral lymphocyte populations, functional T cell subtype Th1 (CD3+CD4+IFN‐r+), Th2 (CD3+CD4+IL‐4+), Tc1 (CD3+CD8+IFN‐r+), Tc2 (CD3+CD8+IL‐4+) and mRNA expression of several immune‐active and ‐suppressive molecules including CD25, CD28, cytotoxic T‐lymphocyte‐associated protein 4, programmed cell death protein 1, Foxp3, transforming growth factor beta (TGF‐β) and interleukin (IL‐10) in 16 cancer patients. Results: The results show that local cancer thermal ablation modulated the cellular immunity characterized by obviously downregulation of regulatory T cells (Treg) and cytotoxicity T cells followed by CD4, CD8 and suppressor T cells (Ts), but upregulation of natural killer (NK) cells and mRNA expression of TGF‐β and IL‐10, suggesting a slight inhibition of the cellular immunity which may affect antitumor immunity. Conclusions: We suggest a further immunomodulation therapy after thermal therapy for recovering a Th1‐ and Tc1‐dominant immune response for pursuing a better long‐term antitumor immunity. [ABSTRACT FROM AUTHOR]