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In recent years, TNS has attracted wide attention because of its simplicity in synthesis and high efficiency in ion exchange. The adsorption of cesium ions in aqueous solution by TNS was investigated in this study. Results show that the removal rate of Cs (I) is about 88% when pH = 5.00 ± 0.05, C0 = 10 ppm and CTNS = 0.1 g/L. The adsorption equilibrium is reached in about 20 minutes and best fits the pseudo-second order model, R2 = 0.9998; compared with the Freundlich isotherm adsorption model and Temkin model, the Langmuir model has the best fitting effect, R2 = 0.9903. The fitting results show the maximum adsorption capacity of TNS for Cs (I) is 200.00 mg/g. The main adsorption mechanism of TNS to cesium ion is ion exchange. Therefore, TNS can be used as a potential adsorbent for effectively adsorbing Cs-containing wastewater. HIGHLIGHTS The removal of Cs (I) from aqueous solutions by TNS was firstly studied.; TNS showed a high adsorption capacity for Cs (I).; The solution pH played a significant role in the adsorption process of Cs (I).; TNS exhibited an excellent selectivity for Cs (I) in the interference of common cations.; The adsorption mechanism was the ion exchange between the interlayer Na (I) of TNS and Cs (I).

To effectively protect the marine ecological environment, herein, the silver-loaded organometallic framework material ((MIL-101(Cr)@Ag) was synthesized to study the rapid enrichment of iodide ions. Under the best experimental conditions, the reaction was in adsorption equilibrium within 10 min, and the maximum adsorption capacity could attain 57 mg/g. The XPS and XRD analysis indicated that the iodide ions mainly interacted with silver atoms in MIL-101(Cr)@Ag to form AgI. The adsorption behavior was well fitted by the pseudo-second-order kinetic model and Langmuir isotherm model, showed that adsorption process was mainly monolayer chemisorption. Therefore, MIL-101(Cr)@Ag could be used as a potential material for removing iodide ions from aqueous solutions.

In this paper, a fast and parallelizable method based on Gaussian Processes (GPs) is introduced to emulate computer models that simulate the formation of binary black holes (BBHs) through the evolution of pairs of massive stars. Two obstacles that arise in this application are the a priori unknown conditions of BBH formation and the large scale of the simulation data. We address them by proposing a local emulator which combines a GP classifier and a GP regression model. The resulting emulator can also be utilized in planning future computer simulations through a proposed criterion for sequential design. By propagating uncertainties of simulation input through the emulator, we are able to obtain the distribution of BBH properties under the distribution of physical parameters., 24 pages, 11 figures

A general portfolio of survivorship life insurance contracts is studied in a stochastic rate of return environment with a dependent mortality model. Two methods are used to derive the first two moments of the prospective loss random variable. The first one is based on the individual loss random variables while the second one studies annual stochastic cash flows. The distribution function of the present value of future losses at a given valuation time is derived. For illustrative purposes, an AR(1) process is used to model the stochastic rates of return, and the future lifetimes of a couple are assumed to follow a copula model. The effects of the mortality dependence, the portfolio size and the policy type, as well as the impact of investment strategies on the riskiness of portfolios of survivorship life insurance policies are analyzed by means of moments and probability distributions.

The gold nanoparticles (Au NPs) modified porous silicon chip based surface assisted laser desorption/ionization mass spectrometry (SALDI-MS) was developed to capture and analyze glutathione (GSH) in cells. With silver-assisted chemical etching, Ag nanoparticles (Ag NPs) were generated and deposited on the silicon surface and the nanopores were etched on silicon substrate. Then Au NPs were in-situ synthesized on the ridges of silicon nanopores. This Ag-Au NPs modified porous silicon surface could specially capture and enrich thiol compounds through Au-S binding, and it could also function as matrix to assist ionization for SALDI-MS. The silicon chip was array patterned for high throughput SALDI-MS detection. GSH and cysteine could be distinguished without the interference from matrix signals. This approach was successfully applied to preconcentration and detection of GSH in Caco-2 cells. The GSH alterations in cells under drug stimulation were investigated. This invented silicon chip showed great potential for more efficient analysis of small thiol biomarkers in complex biological samples.

Designed experiments for ANOVA studies are ubiquitous across all areas of scientific endeavor. An important decision facing experimenter is that of the experiment run size. Often the run size is chosen to meet a desired level of statistical power. The conventional approach in doing so uses the lower bound on statistical power for a given experiment design. However, this minimum power specification is conservative and frequently calls for larger experiments than needed in many settings. At the very least, it does not give the experimenter the entire picture of power across competing arrangements of the factor effects. In this paper, we propose to view the unknown effects as random variables, thereby inducing a distribution on statistical power for an experimental design. The power distribution can then be used as a new way to assess experimental designs. It turns out that using the proposed expected power criterion often recommends smaller, less costly, experimental designs.

Histone lysine demethylase 1 (LSD1), the first identified histone demethylase, is overexpressed in multiple tumor types, including breast cancer. However, the mechanisms that cause LSD1 dysregulation in breast cancer remain largely unclear. Here, we report that protein arginine methyltransferase 4 (PRMT4 or CARM1) dimethylates LSD1 at R838, which promotes the binding of the deubiquitinase USP7, resulting in the deubiquitination and stabilization of LSD1. Moreover, CARM1- and USP7-dependent LSD1 stabilization plays a key role in repressing E-cadherin and activating vimentin transcription through promoter H3K4me2 and H3K9me2 demethylation, respectively, which promotes invasion and metastasis of breast cancer cells. Consistently, LSD1 arginine methylation levels correlate with tumor grade in human malignant breast carcinoma samples. Our findings unveil a unique mechanism controlling LSD1 stability by arginine methylation, also highlighting the role of the CARM1-USP7-LSD1 axis in breast cancer progression.

In this paper, we rationally design a novel G-quadruplex-selective luminescent iridium (III) complex for rapid detection of oligonucleotide and VEGF165 in microfluidics. This new probe is applied as a convenient biosensor for label-free quantitative analysis of VEGF165 protein from cell metabolism, as well as for studying the kinetics of the aptamer-protein interaction combination with a microfluidic platform. As a result, we have successfully established a quantitative analysis of VEGF165 from cell metabolism. Furthermore, based on the principles of hydrodynamic focusing and diffusive mixing, different transient states during kinetics process were monitored and recorded. Thus, the combination of microfluidic technique and G-quadruplex luminescent probe will be potentially applied in the studies of intramolecular interactions and molecule recognition in the future.

In this work, a multi-type cell microfluidic integrator for cocultivation and enabling simulation of drug absorption, metabolism, and anticancer activity was developed. To organize an in vitro drug absorption and metabolism model, Caco-2, HepG2, and U251 cells were co-cultured as mimics of the intestine, liver, and glioblastoma, respectively. The HepG2 cell channel was separated from the Caco-2 cell channel by a polycarbonate semipermeable membrane, and connected with the U251 cell channel by a narrow channel array. Microfluidic cell co-culture, irinotecan (CPT-11) metabolism and cytotoxic analysis were performed simultaneously on the chip. This mimic organ-to-organ network carried out long-distance drug transfer under a microflow environment. The drug cytotoxicity assay was monitored by fluorescence visualization. The extra-/intra-cellular CPT-11 and its active metabolite of 7-ethyl-10-hydroxycamptothecin (SN-38) were qualitatively and quantitatively characterized by liquid chromatography-tandem mass spectrometry. It was revealed that prodrug CPT-11 was absorbed by Caco-2 cells and transferred to HepG2 cells through the porous membrane, then CPT-11 transformed to active SN-38 by HepG2 cells. Metabolic SN-38 was pumped out of HepG2 cells and diffused from the HepG2 cell channel toward the U251 cell channel through a connection channel array to targeting U251 cells. Our results suggest that this dynamic 3D device provides a potential application for high throughput drug screening and personalized cancer therapy.

In this work, hybrid microfluidic devices were fabricated by assembling a polydimethylsiloxane (PDMS) mold with an agarose microarray to realize cell capture and patterning in precisely controlled spatial distribution. Microwells with diameter varying from 15 to 30 μm were formed on the agarose hydrogel surface at 15 μm to 40 μm spacing. Cells were efficiently captured in microwells with nearly 100% occupancy, thus achieving cell manipulation in a semi-quantitative manner. The size of the cell population captured on the microwell array is proportional to the patterning area. Further study revealed that the capture process was mainly regulated by fluid dynamics, where liquid was absorbed by the highly permeable agarose substrate and carried target cells into microwells. Our method spared the complex chemical modification steps, and the agarose substrate promised good biocompatibility. By designing PDMS channels with different geometrical layouts, various cell patterning geometries were easily created. Cell culture models with controllable pattern area and population size were successfully developed for a temozolomide stimulation study for as long as 2 days. This work should benefit the study of cancer developing niche and provide a powerful platform for the direct and continuous observation of cell dynamics under drug stimulation.

A rapid development has been witnessed since the birth of this miniaturized analytical equipment about forty years ago. And microfluidics, a discipline studying the manipulation and analysis of micro volume sample is also attracting the attention of academics with the annually increasing publications. At present, microfluidic device has become a powerful platform with diverse functions implicated in the fields of cellular biology, environmental study, food safety monitoring and micro synthesis, and has crossed the barrier of academic study into the daily life of normal customers. In this chapter, we will focus on several aspects concerning the design and fabrication of microfluidic devices, such as the development of device material, different methods of chip fabrication and functional units to realize purpose of intention. And in the end of this part, a brief future perspective is given to evaluate the potential applications of microfluidic device, especially with other portal devices like smart phone.

Interaction between tumor and endothelial cells could affect tumor growth and progression and induce drug resistance during cancer therapy. Investigation of tumor-endothelial cell interaction involves cell coculture, protein detection, and analysis of drug metabolites, which are complicated and time-consuming. In this work, we present an integrated microfluidic device with three individual components (cell coculture component, protein detection component, and pretreatment component for drug metabolites) to probe the interaction between tumor and endothelial cells. Cocultured cervical carcinoma cells (CaSki cells) and human umbilical vein endothelial cells (HUVECs) show higher resistance to chemotherapeutic agents than single-cultured cells, indicated by higher cell viability, increased expression of angiogenic proteins, and elevated level of paclitaxel metabolites under coculture conditions. This integrated microfluidic platform with multiple functions facilitates understanding of the interaction between tumor and endothelial cells, and it may become a promising tool for drug screening within an engineered tumor microenvironment.

This study describes a novel method for single-cell analysis and lipid profiling by combining drop-on-demand inkjet cell printing and probe electrospray ionization mass spectrometry (PESI-MS). Through inkjet sampling of a cell suspension, droplets with single cells were generated, precisely dripped onto a tungsten-made electrospray ionization needle, and immediately sprayed under a high-voltage electric field. Lipid fingerprints of single cells were obtained by a mass spectrometry (MS) detector. A homemade magnetic stirring device was applied to the cell suspension reservoir, which controlled the homogeneous distribution of cells in liquid and improved the single-cell-droplet percentage by 43.8%. Eight types of single cells were screened in our platform and further differentiated by principal component analysis based on cellular surface phospholipids. Thus, this study successfully provides a facile method for the direct MS profiling of single-cell lipids by PESI-MS.

The tailings accident-prone and the method of hazards analysis and identification are highly valued by Canada, Australia, European Union and other countries. These accidents brought huge loss and a profound lesson such as the “9.8” dam break accident of Shan Xi's new tower, which reflected the limitations of our tailings management and the necessity of study. A method about Life cycle oriented hazards identification for tailings facility, and analyzed hazards of life cycle systematically from technical, human, environment and regulations, such as the unsafe state of tailings pond, the miscount of people, the deficiencies of management and the adverse conditions of environment, and the advice of accident disaster prevention measures for the corresponding life cycle stages was presented, the safety level of the tailing pond in China will be improved.

Research towards nucleic acid amplification technologies for detection of human papillomavirus (HPV) 16 E6/E7 mRNA was carried out in combination with microchip electrophoresis (MCE). The approaches of nucleic acid sequence based amplification (NASBA), one-step RT-PCR and two-step RT-PCR were successfully developed. NASBA was a simple enzymatic reaction, which directly amplified HPV16 mRNA by isothermal amplification, leaving out the complex and tedious operation. One-step RT-PCR simplified the amplification step, while two-step RT-PCR was more sensitive and less vulnerable to the interference. Furthermore, instead of gel electrophoresis, microchip electrophoresis (MCE) for RNA assay was employed to realize high-throughput and rapid analysis. Finally, the results show that PCR-based or NASBA-based mRNA tests are valuable for HPV mRNA assay, which can be potentially applied for clinical diagnosis and prognosis of cervical and other anogenital carcinoma.

In this paper, we report a novel sample introduction and chemical reaction strategy by drop-by-drop inkjet injection for an electrophoretically mediated microanalysis (EMMA). This method makes it possible to achieve an on-line introduction of reactant solutions by alternately ejecting small plugs, with an overlapping region of the plugs for mixing the reactants by electrophoresis, supporting chemical reactions, followed by electrophoretic separation of the final compounds. As a proof-of-concept of the method, the EMMA of an inkjetted mixture of 4-fluoro-7-nitrobenzofurazan (NBD-F) and amino acids was carried out as a model chemical reaction. The product NBD-amino acids were quantified by detection with laser induced fluorescence. The optimal conditions for the procedure were: inkjet driving voltage: +40–44 V; pulse width: 20–24 μs; drop-by-drop injection of reactant solutions: alternately 2 drops × 25 times for the amino acid solution and the NBD-F solution; zone overlapping voltage and time: 3 kV and 2 s; incubation time after overlapping: 5 min; separation voltage: 18 kV. Under the optimized conditions, a significant enhancement in sensitivity and a sensitive quantitative analysis were realized. The results obtained were comparable with those using the off-line labeling method. This method is rapid, cost-effective, and readily automated for EMMA.