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Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2, also called IMP2) plays an essential role in the development and maturation of germ cells and embryos and is a candidate gene for goat litter size, based on a previous genome-wide selective sweep analysis. In this study, the mRNA expression level of IGF2BP2 was found to be significantly higher in a single-lamb group than in a multi-lamb group. Insertions/deletions (indels) within the goat IGF2BP2 gene, including P4-Ins-13bp and P5-Del-12bp, were verified in 918 Shaanbei White Cashmere (SBWC) female goats. The minor allelic frequencies (MAFs) of P4-Ins-13bp and P5-Del-12bp loci were 0.349 and 0.295, respectively. Analysis using the Chi-square (χ2) test showed that the genotype (χ2=14.479, P=0.006) distribution of P4-Ins-13bp was significantly different between the single-lamb and multi-lamb groups. Correlation analysis demonstrated that P4-Ins-13bp was significantly associated with goat litter size (P=0.022), and individual goats with the homozygous deletion/deletion (DD) genotype produced more litters than other goats. Therefore, considered as a potential molecular marker significantly related to lambing traits, the P4-Ins-13bp mutation of the goat IGF2BP2 gene can be used in goat breeding with practical molecular marker-assisted selection (MAS) to optimize female reproduction and improve economic efficiency in the goat industry.

Screening appendants on membrane proteins to understand their varied regulation effects is desirable for finding the potential candidates of the membrane-protein-targeted drugs. However, most artif...

The combination of DNA with synthetic polymers paves the way to advanced materials with appealing features, which exploits both the wisdom from nature and the synthetic strength of polymer chemistry. Thus, the last decade witnessed the booming development of this field. This review aims to provide a comprehensive and timely summary of the progress in the past 5 years. First, the background of DNA as a functional building block is provided, and the status quo for DNA modification, editing, and regulating is briefly introduced, followed by highlights of the routes and strategies for generating powerful DNA-containing polymers in the form of macromolecules, supramolecules, and hydrogels. Special attention is paid to the contribution of polymer chemistry to the advances of DNA-containing materials, including click chemistry, controlled radical polymerization, and supramolecular assembly. Then the applications of DNA-containing polymers in the fields of biosensors, drug release, shape-memory materials, and biocompatible media are presented. Lastly, the review provides an overlook of the challenges and opportunities for future developments.

A series of thermoresponsive cationic dendronized copolymers and their corresponding nanogels containing dendritic oligoethylene glycol (OEG) units and guanidine groups were prepared, and their complexation, protection, and release of nucleic acids were investigated. The dendritic OEGs endow these copolymer materials with good biocompatibility and characteristic thermoresponsiveness, while cationic guanidine groups can efficiently bind with the nucleic acids. The dendritic topology also affords the copolymers specific shielding effect which plays an essential role in protecting the activity of nucleic acids. At room temperature, dendronized copolymers and the corresponding nanogels could efficiently capture and condense the nucleic acids, while above their cloud points (Tcps), more than 75% of siRNA could be released in 1 h triggered by ATP. More importantly, the copolymer showed protective capability to siRNA, while nanogels exhibit even better protection when compared to the copolymers due to the synergetic effect from the three-dimensional cross-linked network and high density of dendritic units in vicinity. This kind of smart dendronized copolymer nanogels form a novel class of scaffolds as promising materials for biomedical applications.

Graphene ribbons, which may be fabricated by a wide variety of experimental techniques such as chemical processing, unzipping or etching of carbon nanotubes, molecular precursors, ion implantation,...

Dendronization of polymers enhances the crowding and cooperative effects to provide efficient encapsulation and protection of biomacromolecules, which may provide a new strategy for developing novel advanced biomaterials. In the present work, a class of thermoresponsive dendronized copolymers and their corresponding nanogels were prepared, and their properties as siRNA carriers were investigated. These copolymer materials are constituted with ethoxyl- and amino-terminated dendritic oligoethylene glycol (OEG) moieties to provide thermoresponsiveness and positive charges for specific interaction with siRNA, respectively. Multivalency from the dendritic architecture affords these cationic copolymer materials appropriate compositions for efficient condensation with negatively charged siRNAs, and provides excellent protection for them. Thermoresponsive properties from the OEG dendrons can favorably trigger the release of encapsulated siRNAs through the collapse of copolymer chains upon phase transitions at physiological temperature. In comparison with the copolymers, the corresponding nanogels show favorable propensity to condensate, protect, and efficiently release siRNAs even when a low amount of ammonium units was presented. The enhanced proximity effects from intermolecularly appended dendrons within the spherical morphology of nanogels are remarkable. The nanogels/siRNA complex can be taken up efficiently by the cells, and greatly knock down the expression of target genes. These features guarantee dendronized copolymer-based nanogels as highly promising vectors for gene delivery.

We report fabrication and measurements of hexagonal boron nitride (h-BN)/chemical vapor deposition (CVD) graphene/h-BN heterostructure devices without using expensive, time-consuming electron-beam lithography and toxic carbon tetrafluoride or sulfur tetrafluoride etching. We use efficient transfer of h-BN/CVD graphene by polypropylene carbonate onto a pre-prepared metal contacts/h-BN/SiO2 substrate. In this case, CVD-graphene is suspended from the h-BN substrate which allows efficient gas annealing process for improving the device mobility. Interestingly, we find that the top h-BN capping layer could enhance the carrier interference effect in CVD graphene, a great advantage for low-cost graphene-based interference-type electronic devices.

2,4,5-Trichloro-6-((2,4,6-trichlorophenyl)amino)isophthalonitrile (SYD007) is a small molecule compound that was synthesized according to the structure of diarylamine. In this study, we evaluated the anti-bladder activities of SYD007, and determined its cytotoxic mechanism. We found that SYD007 exerted cytotoxicity to bladder cancer cells. Furthermore, SYD007 induced bladder cancer cell early apoptosis and arrested cell cycle. Mechanistically, SYD007 suppressed phosphorylated signal transducer and activator of transcription 3 (p-STAT3) (Tyr705) level in parallel with increases of p-extracellular signal-regulated kinase (ERK) and p-AKT. SYD007 significantly inhibited insulin-like growth factor 1 (IGF-1)-induced STAT3 activation through down-regulation of total IGF-1R level. No dramatic changes in IGF-1R mRNA levels were observed in SYD007-treated cells, suggesting that SYD007 acted primarily at a posttranscriptional level. Using molecular docking analysis, SYD007 was identified as an IGF-1R inhibitor. In summary, we reported that SYD007 exerted anti-bladder activities, and these effects were partially due to inhibition of IGF-1R/STAT3 signaling.

Confined microenvironments in biomacromolecules arising from molecular crowding account for their well-defined biofunctions and bioactivities. To mimick this, synthetic polymers to form confined structures or microenvironments are of key scientific value, which have received significant attention recently. To create synthetic confined microenvironments, molecular crowding effects and topological cooperative effects have been applied successfully, and the key is balance between self-association of structural units and self-repulsion from crowding-induced steric hindrance. In this article, formation of confined microenvironments from stimuli-responsive dendronized polymers carrying densely dendritic oligoethylene glycols (OEGs) moieties in their pendants is presented. These wormlike thick macromolecules exhibit characteristic thermoresponsive properties, which can provide constrained microenvironments to encapsulate effectively guest molecules including dyes, proteins, or nucleic acids to prevent their protonation or biodegradation. This efficient shielding effect can also mediate chemical reactions in aqueous phase, and even enhance chirality transferring efficiency. All of these can be switched off simply through the thermally-induced dehydration and collapse of OEG dendrons due to the amphiphilicity of OEG chains. Furthermore, the switchable encapsulation and release of guests can be greatly enhanced when these dendronized polymers are used as major constituents for fabricating bulk hydrogels or nanogels, which provide a higher-level confinement.

OBJECTIVES: To investigate the fatty acids composition in different lactation stages of human milk in China. METHODS: A large cross-sectional study was conducted and lactating women (n = 6481) within 0–330 days postpartum were recruited in China between 2011 and 2013. Human milk sub-samples (n = 1135) were randomly selected for fatty acids analysis in the original study. The sample size of colostrum, transitional milk, and mature milk were 160, 177, 798 respectively. Fats were hydrolyzed and fatty acids methyl esters were analyzed using gas chromatography. RESULTS: The content of oleic acid, the highest level fatty acid in human milk, was 36.63%, 34.53% and 35.12% of total fatty acids in colostrum, transitional milk, and mature milk, respectively in China. The content of palmitic acid was about 23.69%, 21.90% and 20.82% in colostrum, transitional milk, and mature milk, respectively. Saturated fatty acids, monounsaturated fatty acids and polyunsaturated fatty acids accounted for 36.99%, 39.14% and 23.49% of total fatty acids of mature milk, respectively. The content of linoleic acid and arachidonic acid was 20.47% and 0.54% in mature milk, respectively. The content of eicosapentaenoic acid (EPA) and docosahexenic acid (DHA) was 0.06% and 0.28% in mature milk, respectively. In addition to lactation stage, the fatty acids content differed significantly among various regions, nationalities, or mode of delivery. (i.e., Regions (city vs rural): oleic acid: 33.8% vs 36.4%; linoleic acid: 22.88% vs 17.21%; arachidonic acid:0.64%vs 0.59%; DHA: 0.42% vs 0.26%; EPA: 0.09% vs 0.04%. Nationality (Han vs Minority): oleic acid: 34.40% vs 36.59%; linoleic acid: 21.69% vs 16.54%; arachidonic acid:0.64%vs 0.57%; DHA: 0.38% vs 0.24%; EPA: 0.08% vs 0.04%.). CONCLUSIONS: Oleic acid is the most abundant fatty acids in human milk of China. In addition to lactation stage, the fatty acid concentrations vary among different regions and nationalities in China. FUNDING SOURCES: This study was supported by Beijing Natural Science Foundation (S160002), the National Key R&D Program of China (2017YFD0400601) and the National High Technology Research and Development Program of China (863 Program) (2010AA023004).

The SRY-type HMG box 9 (Sox9) gene plays an important role in chondrocyte development as well as changes in hypertrophic chondrocytes, indicating that Sox9 can regulate growth in animals. However, no studies to date have examined the correlation between variations in Sox9 and growth traits in goats. Here, we found a 4 bp indel in the 3&prime, UTR of Sox9 and verified its association with growth traits in Shaanbei white cashmere goats (n = 1109). The frequencies of two genotypes (ID and II) were 0.397 and 0.603, respectively, and polymorphic information content (PIC) values showed that the indel had a medium PIC (PIC &gt, 0.25). The 4 bp indel was significantly correlated with body length (p = 0.006), heart girth (p = 0.001), and hip width (p = 4.37 &times, 10 &minus, 4). Notably, individuals with the ID genotype had significantly superior phenotypic traits compared with individuals bearing the II genotype. Hence, we speculated that the 4 bp indel is an important mutation affecting growth traits in goat, and may serve as an effective DNA molecular marker for marker-assisted selection in goat breeding programs.

Several graphene quantized Hall resistance (QHR) devices manufactured at the National Institute of Standards and Technology (NIST) were compared with GaAs QHR devices and a 100- $\Omega $ standard resistor at the National Institute for Advanced Industrial Science and Technology (AIST). Measurements of a 100- $\Omega $ resistor with graphene QHR devices agreed within 5 $\text{n}\Omega /\Omega $ of the values for a 100- $\Omega $ resistor obtained through GaAs measurements. The electron density of the graphene devices was adjusted at AIST to restore device properties such that operation was possible at low magnetic flux densities of 4–6 T. This adjustment was accomplished by a functionalization method utilized at NIST, allowing for consistent tunability of the graphene QHR devices with simple annealing. Such a method replaces older and less predictable methods for adjusting graphene for metrological suitability. The milestone results demonstrate the ease with which graphene can be used to make resistance comparison measurements among many National Metrology Institutes (NMIs).

Homogeneous, single-crystal, monolayer epitaxial graphene (EG) is the one of most promising candidates for the advancement of quantized Hall resistance (QHR) standards. A remaining challenge for the electrical characterization of EG-based quantum Hall devices as a useful tool for metrology is that they are electrically unstable when exposed to air due to the adsorption of and interaction with atmospheric molecular dopants. The resulting changes in the charge carrier density become apparent by variations in the surface conductivity, the charge carrier mobility, and may result in a transition from n-type to p-type conductivity. This work evaluates the use of Parylene C and Parylene N as passivation layers for EG. Electronic transport of EG quantum Hall devices and non-contact microwave perturbation measurements of millimeter-sized areas of EG are both performed on bare and Parylene coated samples to test the efficacy of the passivation layers. The reported results, showing a significant improvement in passivation due to Parylene deposition, suggest a method for the mass production of millimeter-scale graphene devices with stable electrical properties.

In this paper, a novel prototype liquid-air dual gradient chip is introduced, which has paved the way for effective synergic effect bio-evaluation of air pollutant. The chip is composed of an array of the agarose liquid-air interfaces, top air gradient layer and bottom liquid gradient layer. The novel agarose liquid-air interface allows for non-biased exposure of cells to all the substances in the air and diffusive interactions with the liquid phase; while the dual liquid-air gradient provides powerful screening abilities, which well reduced errors, saved time and cost from repeated experiment. Coupling the two functions, the chip subsequently facilitates synergic effect evaluation of both liquid and air factors on cells. Here cigarette smoke was taken as the model air pollutant, and its strong synergic effects with inflammatory level of A549 lung cancer cells on their fate were successfully quantified for the first time. These results well testified that the proposed dual-gradient chip is powerful and indispensable for bio-evaluation of air pollutant.

In an attempt to arrive at a more potent cytotoxic agent than the parent compound α-hederagenin (H), 24 α-hederagenin derivatives (5–8, 11–24, 27–28, 31–32, and 35–36) were synthesized in a concise and efficient strategy and screened for in vitro cytotoxicity against the human cancer cell lines MKN45 and KB. Among these compounds, the polyamine derivative 15 exhibited more potency than the parent compound with IC50 values in the range of 4.22 μM–8.05 μM. Compound 15 increased Bax/bcl-2 ratio that disrupted the mitochondrial potential and induced apoptosis. Therefore, the present studies highlight the importance of polyamine derivatives of α-hederagenin in the discovery and development of novel anticancer agents.

In order to improve the strength and toughness of the C/C-HfC-ZrB2-SiC composites, uniformly distributed SiC nanowires were in situ grown in C/C preform using a simple precursor infiltration pyrolysis method with ferrocene as catalyst. The SiC nanowires could greatly refine the size of the ultra-high temperature ceramic (HfC-ZrB2-SiC) particles, and make the ceramic particles interconnected with the unitary body. After introducing SiC nanowires, the flexural strength, flexural modulus and fracture toughness of the composites increased by 21%, 29% and 28% respectively, due to interfacial weakening, the deflection of cracks induced by SiC nanowires and the pullout of SiC nanowires. The C/C-HfC-ZrB2-SiC composites with SiC nanowires also displayed good erosion resistance under high velocity Al 2 O 3 particle erosion.

We have performed extensive transport experiments on a 4 nm thick aluminum (Al) superconducting film grown on a GaAs substrate by molecular beam epitaxy (MBE). Nonlinear current-voltage (I-V) measurements on such a MBE-grown superconducting nanofilm show that V ∼ I 3, which is evidence for the Berezinskii-Kosterlitz-Thouless (BKT) transition, both in the low-voltage (T BKT ≈ 1.97 K) and high-voltage regions (T BKT ≈ 2.17 K). In order to further study the two regions where the I-V curves are BKT-like, our experimental data are fitted to the temperature-induced vortices/antivortices unbinding model as well as the dynamical scaling theory. It is found that the transition temperature obtained in the high-voltage region is the correct T BKT as confirmed by fitting the data to the aforementioned models. Our experimental results unequivocally show that I-V measurements alone may not allow one to determine T BKT for superconducting transition. Therefore, one should try to fit one's results to the temperature-induced vortices/antivortices unbinding model and the dynamical scaling theory to accurately determine T BKT in a two-dimensional superconductor.

Microfluidic paper analytical devices (μPADs) are smart and accessible substituents to traditional counterparts in point-of-care tests (POCT), which exploited delicate control over passive fluid in microscale for rich functions. In this work, we are extending such control by introducing novel ways to generate 1D and 2D gradients on μPADs. It is achieved by using paper-capillary-based serial sampling. The paper capillary is composed of a concaved paper channel sealed with tape, with test pads properly distributed aside. In such a structure, the liquid can not only quickly and automatically flow along the capillary but also be continuously consumed by the peripheral test pads. Thus, when we do serial sampling, an abnormal liquid chasing effect can be observed, where the later liquid sample chases and surpasses the earlier parts in the paper capillary, leading to reversely ordered sample distribution compared with that in a typical glass capillary. This specialty allows for fast, ordered, and tunable sequential sampling and enables efficient generation of 1D and 2D concentration gradient with one, two, and even three components on μPADs. Besides, we verified the applicability of this technique for arrayed assays, including 1D serial dilution-based metal ion colorimetry and a 2D bacterial antibiotic susceptibility test for synergic effect evaluations, which paves the way for high-throughput sample analysis and information-rich condition screening on μPADs.

Monolayer epitaxial graphene (EG) has been shown to have clearly superior properties for the development of quantized Hall resistance (QHR) standards. One major difficulty with QHR devices based on EG is that their electrical properties drift slowly over time if the device is stored in air due to adsorption of atmospheric molecular dopants. The crucial parameter for device stability is the charge carrier density, which helps determine the magnetic flux density required for precise QHR measurements. This work presents one solution to this problem of instability in air by functionalizing the surface of EG devices with chromium tricarbonyl -Cr(CO)(3). Observations of carrier density stability in air over the course of one year are reported, as well as the ability to tune the carrier density by annealing the devices. For low temperature annealing, the presence of Cr(CO)(3) stabilizes the electrical properties and allows for the reversible tuning of the carrier density in millimeter-scale graphene devices close to the Dirac point. Precision measurements in the quantum Hall regime show no detrimental effect on the carrier mobility.

Though microfluidic paper analytical devices (μPADs) have attracted paramounting attentions in recent years as promising devices for low cost point-of-care tests, their real applications for blood analysis are still challenged by integrating sample preparation with different detection modes on a same μPAD. Herein, we developed a novel μPAD, which well coupled automatic serum extraction with reliable dual mode iron health tests: fluorescent analysis for Fe3+ and colorimetric ELISA for ferritin. All these functions are made available by in situ carbon dots (CDs) and AuNPs sequential patterning techniques. For CDs immobilization, hydrothermal reaction was taken on paper, to which a patterned through-hole polydimethylsiloxane (PDMS) mask was applied. None fluorescence CDs (nF-CDs) were generated on exposed regions, while the fluorescent CDs (F-CDs) were generated simultaneously on covered regions. Sensitive serum iron quantification was realized on the F-CDs modified regions, where Fe3+ ion can selectively qu...

In this paper, we propose a generalized concept of microfluidic polydimethylsiloxane (PDMS) on paper (POP) devices, which combines well the merits of paper chips and PDMS chips. First, we optimized the conditions for accurate PDMS spatial patterning on paper, based on screen printing and a high temperature enabled superfast curing technique, which enables PDMS patterning to an accuracy of tens of microns in less than ten seconds. This, in turn, makes it available for seamless, reversible and reliable integration of the resulting paper layer with other PDMS channel structures. The integrated POP devices allow for both porous paper and smooth channels to be spatially defined on the devices, greatly extending the flexibility for designers to be able to construct powerful functional structures. To demonstrate the versatility of this design, a prototype POP device for the colorimetric analysis of liver function markers, serum protein, alkaline phosphatase (ALP) and aspartate aminotransferase (AST), was constructed. On this POP device, quantitative sample loading, mixing and multiplex analysis have all been realized.

A novel precursor infiltration and pyrolysis (PIP) technique was used to in-situ synthesize SiC nanowires (NWs) on C/C composites, and then pack cementation was applied to prepare a silicide coating. The results show that the NWs could not only grow uniformly on the C/C surface but also be synthesized in some microholes through PIP technique. During thermogravimetry tests from 800 °C to 1400 °C in simulated air, the mass loss of the coated specimen decreased from 11.8% to 1.5% after incorporating PIP-SiC NWs. The introduction of PIP-SiC NWs also increased the thermal shock resistance of the coated specimens. After 24 times thermal cycles between room temperature and 1500 °C, the final mass loss reduced from 3.23% to 0.37%. The improvement of thermal shock resistance of the coated specimens was owing to the nanoscale toughening mechanism including pulling-out, debonding and bridging of PIP-SiC NWs. In addition, NWs at the coating/substrate interface could play as a barrier to restrain the propagation of microcrack and thus decreased the size of micocrack.

We report the fabrication and measurement of top gated epitaxial graphene p-n junctions where exfoliated hexgonal boron nitride (hBN) is used as the gate dielectric. The four terminal longitudinal resistance across a single junction is well quantized at $R_{\text{K} -90}(=25812.807\ \Omega)$ with a relative uncertainty of 10−7. Our work opens the possibility to realize programmable electrical resistance standards using external gating.

Two graphene quantized Hall resistance (QHR) devices made at the National Institute of Standards and Technology (NIST) were hand carried to the National Institute for Advanced Industrial Science and Technology (AIST) and compared to a $\mathbf{GaAs}$ QHR device and a $\pmb{100 \ \Omega}$ standard resistor. Measurement of the $\pmb{100\ \Omega}$ resistor with the graphene QHR devices agreed within $\pmb{5}\ \mathbf{x}\ \pmb{10^{-9}}$ of the $\pmb{100\ \Omega}$ resistor $\mathbf{GaAs}$ measurements. After the initial measurements, the carrier density of the graphene devices was adjusted at AIST to restore the device properties to operate at low magnetic fields of 4 T to 6 T.

The information provided in this data article will cover the growth parameters for monolayer, epitaxial graphene, as well as how to verify the layer homogeneity by confocal laser scanning and optical microscopy. The characterization of the subsequently fabricated quantum Hall device is shown for example cases during a series of environmental exposures. Quantum Hall data acquired from a CYTOP encapsulation is also provided. Data from Raman spectroscopy, atomic force microscopy, and other electrical property trends are shown. Lastly, quantum Hall effect data are presented from devices with deposited Parylene C films measuring 10.7 μm and 720 nm. All data are relevant for Rigosi et al. [1].

A novel solid-phase extraction (SPE) system, based on a new sorbent of Nylon6/Polypyrrole (PA6/PPy) core–shell nanofibres mat and a new packing format of SPE disks, is presented in this paper. A series of related parameters that may affect the efficiency, such as the kind of eluent and its volume, the amount of nanofibres mat, ionic strength, pH of the sample, flow rate of the sample and volume of the sample, have been investigated systematically. Under the optimised conditions, the target analyte in 10 mL water samples can be completely extracted by a 3.0 mg PA6/PPy nanofibres mat and easily eluted by 400 µL acetonitrile. Around 20 µL elution was injected directly to HPLC-UV for determination, without further concentration. Besides, the nanofibres mat could be repeatedly used up to six cycles. Satisfactory linearity was achieved in the range of 0.1–40.0 ng/mL with a correlation coefficient of 0.9999. The limit of detection (LOD) (3 S/N) was 0.03 ng/mL, which could meet the determination requirements of a...

The present study describes a novel sample preparation technique for phenolic environmental estrogens (PEEs), including bisphenol A (BPA), nonylphenol (NP) and octylphenol (OP), in environmental water samples. A hydrazine-modified polyacrylonitrile (HM-PAN) nanofiber mat, with subsequent amino group functionalization, was prepared using the electrospinning technique. A disk solid-phase extraction (SPE) was developed utilizing the functional nanofiber mat as a sorbent for extraction of PEEs prior to high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The critical factors affecting the extraction efficiency of the sorbent for the target analytes were tested and optimized. Under optimized conditions, a simple and fast sample preparation procedure was achieved using a home-made disk SPE device, with noticeably reduced sorbent bed mass (4.0 mg) and eluent volume (600 μL). The detection limits for the targeted PEEs were in the range of 0.01–0.03 ng mL−1 (S/N = 3). We validated the applicability of the proposed method using four real environmental water samples and satisfactory spiked recoveries were achieved in the range of 84.6–101.9% with low RSD ≤ 8.6% (n = 6). A comparison of the present method with the existing methods for the determination of PEEs was made and the results showed that the proposed method had better recoveries, sensitivity and reproducibility. The results demonstrated that the HM-PAN nanofiber mat-based SPE technique was a viable alternative for sensitive and precise analysis of PEEs in environmental water.

Carboxyl modified polyacrylonitrile nanofibers mat (COOH-PAN NFsM) was prepared as a novel solid-phase extraction (SPE) adsorbent for the rapid and effective extraction of atrazine (ATZ) and its toxic metabolites deisopropylatrazine (DIA) and deethylatrazine (DEA) from environmental water samples. Without any pre-treatment but only with the simple filter, water samples passed through pre-conditioned COOH-PAN NFsM, which integrated extraction, purification and concentration into one single step, and the eluent was directly analyzed by high performance liquid chromatography-diode array detection (HPLC-DAD). Under the optimized conditions, the target analytes in 10 mL of water sample could be completely extracted by only 4 mg of COOH-PAN NFsM, and easily eluted using 400 μL of methanol, indicating a high efficiency in both adsorption and desorption. Satisfactory linearity was achieved in the range of 0.4–40.0 ng mL −1 for DIA, and 0.3–40.0 ng mL −1 for DEA and ATZ. The limit of detection (LODs) were 0.12, 0.09 and 0.09 ng mL −1 for DIA, DEA and ATZ, respectively. The recoveries ranged from 81.35 to 120.32%, with the intra-day and inter-day relative standard deviations of 4.03–9.81% even after the 6-cycle usage of NFsM. And, using just 10 mL loading sample, the LOD had already satisfied the demand of surface water quality monitoring levels, revealing the good sensitivity of the proposed method.

In this work, we report a novel microfluidic gas collecting platform aiming at simultaneous sample extraction and multiplex mass spectrometry (MS) analysis. An alveolar-mimicking elastic polydimethylsiloxane (PDMS) structures was designed to move dynamically driven by external pressure. The movement was well tuned both by its amplitude and rhythm following the natural process of human respiration. By integrating the alveolar units into arrays and assembling them to gas channels, a cyclic contraction/expansion system for gas inhale and exhale was successfully constructed. Upon equipping this system with a droplet array on the alveolar array surface, we were able to get information of inhaled smoke in a new strategy. Here, with cigarette smoke as an example, analysis of accumulation for target molecules during passive smoking is taken. Relationships between the breathing times, distances away from smokers and inhaled content of nicotine are clarified. Further, by applying different types of extraction solvent droplets on different locations of the droplet array, simultaneous extraction of nicotine, formaldehyde and caproic acid in sidestream smoke (SS) are realized. Since the extract droplets are spatially separated, they can be directly analyzed by MS which is fast and can rid us of all complex sample separation and purification steps. Combining all these merits, this small, cheap and portable platform might find wide application in inhaled air pollutant analysis both in and outdoors.

A novel disks solid phase extraction (SPE) based on polypyrrole (PPy) functionalized core-shell electrospun nanofibers mat was proposed. The performance of the established disks SPE technique was evaluated in the extraction of trace polar analytes from environmental water samples. Disulphonated (acid yellow 9) and monosulphonated azo dyes (acid orange 7 and metanil yellow) were selected as typical model analytes. Under the optimum conditions, detection limits were 0.15-0.3 μg/L for all target analytes and the enrichment coefficients were 106-121. The recoveries of sulfonated azo dyes added to typical environmental water samples were 87.6-112.3%, suggesting that the interferences of the sample matrix did not affect the enrichment. Compared with existing methods, the device in this study showed higher recovery, lower detection limit and better precision. Moreover, the miniaturized disks SPE technique for sample preparation is simple and fast, with significantly reduced sorbent bed mass (2.5 mg) and eluent volume (500 μL). These results indicate that PPy nanofibers mat-based disks SPE may be a promising device that can effectively extract the polar species in water samples.

A branched electrode platform was proposed for label-free and reagentless simultaneous tumor markers detection based on different redox substrates.

Ohmefentanyl is a very potent and highly selective agonist for mu-opioid receptors. We now study analgesia, in vitro activity and opioid receptor affinity of the stereoisomers of ohmefentanyl isothiocyanate. We found that some isomers of ohmefentanyl isothiocyanate had a potent analgesic effect and that all isomers except (3R,4S,2'S)-ohmefentanyl isothiocyanate had a more potent inhibitory action on the electrically evoked contractions of mouse vas deferens than of guinea pig ileum. The inhibitory actions could be antagonized by naloxone. However, compared with the activity of the corresponding stereoisomers of ohmefentanyl, these ohmefentanyl isothiocyanates had significantly reduced analgesia and in vitro activity. They also inhibited the binding of [3H]DPDPE ([D-Pen(2),D-Pen(5)]enkephalin) and [3H]DAGO ([D-Ala(2),Mephe(4),Gly-ol(5)]enkephalin) to opioid receptors in mouse brain membranes. The inhibitory effect of stereoisomers of ohmefentanyl isothiocyanate at mu-opioid receptors was markedly lower than that of their parent compounds. The affinity of stereoisomers of ohmefentanyl isothiocyanate for delta-opioid receptors was, however, greater than or equal to that of their corresponding stereoisomers of ohmefentanyl. The results showed that the introduction of an isothiocyanato group into the phenyl ring in position-1 of ohmefentanyl reduced bioactivity and affinity to mu-opioid receptors but that the selectivity of these compounds for delta-opioid receptors was enhanced. Isomer (3R,4S,2'R)-ohmefentanyl isothiocyanate showed highest selectivity for delta-opioid receptors (K(i)(mu)/K(i)(delta)=13.6) and potent analgesic activity (ED(50)=0.25 mg/kg).

The analgesic activity and opioid receptor binding characteristics were studied for the isothiocyanate ohmefentanyl (OMFIT), and isothiocyanate carfentanil (CarFIT), isothiocyanate 4-methoxymethylfentanyl (MethoFIT), isothiocyanate 3-methyl-fentanyl (superFIT) and their amide analogs. Antinociceptive activity was evaluated using the mouse hot plate test; selectivity for opioid receptor was determined in bioassay and binding assay. SuperFIT, CarFIT, OMFIT and MethoFIT exhibited an analgesic ED 50 lower than those of their parent compounds without isothiocyanate (SCN) group. Furthermore these compounds exhibited potent inhibitory actions on the electrically evoked contractions of mouse vas deferens, which could be antagonized by naloxone, but their actions were weaker than those of their parent compounds without SCN-group. The inhibitory actions of these compounds on binding of [ 3 H]OMF to mouse brain membrane was weaker than those of their parent compounds without SCN-group. CarFIT and MethoFIT showed weaker inhibitory actions on the binding of [ 3 H] DADLE than their parent compounds without SCN-group, but SuperFIT and OMFIT stronger than their parent compounds, 3-methylfentanyl and ohmefentanyl. The selectivity of these isothiocyanate derivatives for δ opioid receptors increased. In conclusion, introducing isothiocyanato-group into 1-position of phenyl ring of ohmefentanyl and other fentanyl analogs would enhance the selectivity of these compounds for δ-opioid receptors, but decrease their analgesic activity.

This paper introduced the technique of Asymptotic Waveform Evaluation (AWE) applied to the Finite element-boundary integral with Multilevel Fast Multipole Algorithm (FE-BI-MLFMA) for radar cross section (RCS) estimation over a frequency band. A pseudo-derivative method is adopted to overcome the difficulty of using MLFMA in conventional AWE implementation. The accuracy and efficiency of this method are demonstrated by numerical examples.

An electrochemical method for the simultaneous detection of two different tumor markers, carcinoembryonic antigen (CEA) and α-fetoprotein (AFP), in one-pot, using CdS/DNA and PbS/DNA nanochains as labels was developed. Herein, magnetic beads (MBs) as bimolecule immobilizing carriers, were used for co-immobilization of primary anti-CEA and anti-AFP antibodies. The distinguishable signal labels were synthesized by in situ growth of CdS and PbS nanoparticles on DNA chains, respectively, which were further employed to label the corresponding secondary antibodies. A sandwich-type immunoassay format was formed by the biorecognition of the antigens and corresponding antibodies. The assay was based on the peak currents of Cd 2+ and Pb 2+ dissolved from CdS and PbS nanoparticles by HNO 3 using square wave stripping voltammetry. Experimental results show that the multiplexed electrochemical immunoassay has enabled the simultaneous monitoring of CEA and AFP in a single run with wide working ranges of 0.1– 100 ng mL −1 for CEA and 0.5–200 ng mL −1 for AFP. The detection limits reach to 3.3 pg mL −1 for CEA and 7.8 pg mL −1 for AFP.

In this paper, one-step air plasma treatment is successfully used for poly(dimethylsiloxane)(PDMS)-plastic chip bonding. The technique is green, cheap, and requires no other reagent other than air. Hydrocarbon plastics: polystyrene (PS), cyclic olefin copolymer (COC), and polypropylene (PP) have all been successfully bonded to PDMS irreversibly. The corresponding compressed air resistances are measured to be around 500 kPa for PDMS-PS, PDMS-COC, and PDMS-PP hybrid chips. The bondings are also of good quality even after storage under different temperatures and subject to solutions from acid to base.

In this study, a simple and economical fabrication technique bridging micro- and nanostructures is proposed. Glass molds with micro-nanostructures are fabricated by glass microlithography. The microlithography provides flexibility for structure design, and the glass etching contributes to transform the micro glass ridge to the nanoscale. Glass ridge structures with triangular cross sections are generated by undercutting, which coupled the isotropic character of glass and the shield effect of the top Cr layer upon HF etching. Further etching induced the height of the glass ridges to shrink from micro- to nanometres due to the edge effects. At the late etching stage, the geometrical change of the glass greatly slows down, which gives better control over the size of the glass ridge. By glass structure mold-copy, well repeatable, mechanically stable and tunable polydimethylsiloxane (PDMS) channels and cones are fabricated. Scanning electron microscopy (SEM) and laser interferometry (LI) are carried out to characterize the micro-nanostructures. To demonstrate their workability, sample preconcentration to a single nanochannel level is carried out.

This paper reports a new fabrication method of lithography-free nanochannel array. It is based on the cracking process on the surface of a polystyrene (PS) Petri-dish, one type of thermoplastic that is composed of uni-axial macromolecular chains. Under proper conditions, parallel nanochannels with equal interspaces are obtained. Control over the channel depth from 20 nm to 200 nm is achieved, with the channel length reaching tens of millimetres. The PDMS replication based on PS nanochannel array has been successfully carried out. In combination with the microstructure, both an ion enrichment device and a current rectification device are fabricated, and their quantified characters manifested the applicability of the channel array structure in nanofluidics.

In the title compound, [Mn(2)(C(8)H(3)NO(6))(2)(C(12)H(8)N(2))(2)(H(2)O)(4)], the Mn(II) atom in the centrosymmetric binuclear unit has a distorted octa-hedral geometry and is coordinated by a chelating 1,10-phenanthroline ligand, two monodentate carboxyl-ate anions from two 4-nitro-phthalates and two coordinated water mol-ecules. The two Mn(II) ions in the mol-ecule are bridged by two 4-nitro-phthalate anions, both in a bis-monodentate mode, which finally leads to the formation of the binuclear unit. Intra-molecular O-H⋯O hydrogen bonds between the coordinated and uncoordinated O atoms of one monodentate carboxyl-ate group and the corresponding coordinated water mol-ecules result in an eight-membered and two six-membered rings. In the crystal structure, inter-molecular O-H⋯O hydrogen bonds link the dinuclear mol-ecules into supra-molecular chains propagating parallel to [100].

Based on the ingenious combination of two different gradient generation mechanisms, this work reports a novel approach for a high throughput linear liquid gradient in a two-dimensional (2D) matrix. Specifically, a typical Christmas Tree structure with two inlets was designed as the first mixture gradient generator, upon which the second diffusion gradient generator was coupled to produce the desired concentration series on the basis of the distance difference. Rather than a simple 1D line, the integration of the two generators would result in an innovative 2D matrix of reservoirs, which was then characterized both theoretically and experimentally. Theoretically, calculation of fluid field demonstrated the formation of a concentration gradient, which was then confirmed by the dye solution visualization analysis. For high throughput screening application, doxorubicin (Dox) was then selected as model medicine to treat the acute myeloblastic leukemia (HL-60) cells. Cell viability displayed that cell death rate enhanced with the increase of drug concentration, and this result was higher than that on a 96-well plate, and the corresponding mechanism was properly discussed. Subsequently, Dox and quercetin were employed simultaneously to generate an overlapping gradient and its effect on HL-60 cells was investigated. Due to the automatic formation of concentration gradient that could improve the work efficiency, this work provides a promising tool for future high throughput drug screening.

A functionalized nylon6/polypyrrole core-shell nanofibers mat (PA6/PPy NFM) was prepared via situ polymerization on nylon6 electrospun nanofibers mat (PA6 NFM) template and used as an adsorbent to remove atrazine from aqueous solutions. The core-shell structure of PA6/PPy NFM can be clearly proved under scanning electron microscope (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The effects of initial solution pH and ionic strength, as well as the comparison of the adsorption capacity of functionalized (PA6/PPy NFM) and non-functionalized (PA6 NFM) adsorbent, were examined to reveal the possible adsorption mechanism. The results indicated that π-π interaction and electrostatic interaction should play a key role in the adsorption process. The kinetics and thermodynamics studies also further elucidated the detailed adsorption characteristics of atrazine removal by PA6/PPy NFM. The adsorption of atrazine could be well described by the pseudo-second-order equation. The adsorption equilibrium data was well fitted with the Freundlich isotherm model with a maximum adsorption capacity value of 14.8 mg/g. In addition, the increase of adsorption rate caused by a temperature increase could be felicitously explained by the endothermic reaction. The desorption results showed that the adsorption capacity remained almost unchanged after six adsorption/desorption cycles. These results suggest that PA6/PPy NFM could be employed as an efficient adsorbent for removing atrazine from contaminated water sources.