Self-powered microfluidic chips for multiplexed protein assays from whole blood

We report herein on a self-powered, self-contained microfluidic-based chip designed to separate plasma from whole blood, and then execute an assay of a multiplexed panel of plasma biomarker proteins. The power source is based upon a chemical reaction that is catalytically triggered by the push of a button on the chip. We demonstrate assays of a dozen blood-based protein biomarkers using this automated, self-contained device. This platform can potentially permit high throughput, accurate, multiplexed blood diagnostic measurements in remote locations and by minimally trained individuals

The crossover from two dimensions to one dimension in granular electronic materials

Granular conductors1 are solids comprising densely packed nanoparticles, and have electrical properties that are determined by the size, composition and packing of the composite nanoparticles. The ability to control these properties in two- and three-dimensional granular conductors has made such systems appropriate for use as prototypes for investigating new physics1, 2, 3, 4. However, the fabrication of strictly one-dimensional granular conductors remains challenging. Here, we describe a method for the assembly of nanoparticles into granular solids that can be tuned continuously from two to one dimension, and establish how electron transport evolves between these limits. We find that the energy barriers to transport increase in the one-dimensional limit, in both the variable-range-hopping (low-voltage) and sequential-tunnelling (high-voltage) regimes. Furthermore, in the sequential-tunnelling regime we find an unexpected relationship between the temperature and the voltage at which the conductance becomes appreciable — a relationship that appears peculiar to one-dimensional systems. These results are explained by extrapolating existing granular conductor theories to one dimension

A robotics platform for automated batch fabrication of high density, microfluidics-based DNA microarrays, with applications to single cell, multiplex assays of secreted proteins

Microfluidics flow-patterning has been utilized for the construction of chip-scale miniaturized DNA and protein barcode arrays. Such arrays have been used for specific clinical and fundamental investigations in which many proteins are assayed from single cells or other small sample sizes. However, flow-patterned arrays are hand-prepared, and so are impractical for broad applications. We describe an integrated robotics/microfluidics platform for the automated preparation of such arrays, and we apply it to the batch fabrication of up to eighteen chips of flow-patterned DNA barcodes. The resulting substrates are comparable in quality with hand-made arrays and exhibit excellent substrate-to-substrate consistency. We demonstrate the utility and reproducibility of robotics-patterned barcodes by utilizing two flow-patterned chips for highly parallel assays of a panel of secreted proteins from single macrophage cells

Thermoelectric transport properties of diamond-like Cu_(1−x)Fe_(1+x)S_2 tetrahedral compounds

Polycrystalline samples with the composition of Cu _(1−x)Fe_(1+x)S_2 (x = 0, 0.01, 0.03, 0.05, 0.1) were synthesized by a melting-annealing-sintering process. X-ray powder diffraction reveals all the samples are phase pure. The backscattered electron image and X-ray map indicate that all elements are distributed homogeneously in the matrix. The measurements of Hall coefficient, electrical conductivity, and Seebeck coefficient show that Fe is an effective n-type dopant in CuFeS_2. The electron carrier concentration of Cu_(1−x)Fe_(1+x)S_2 is tuned within a wide range leading to optimized power factors. The lattice phonons are also strongly scattered by the substitution of Fe for Cu, leading to reduced thermal conductivity. We use Debye approximation to model the low temperature lattice thermal conductivity. It is found that the large strain field fluctuation introduced by the disordered Fe ions generates extra strong phonon scatterings for lowered lattice thermal conductivity

Microstructure Characterization and Mechanical Properties of TiSi 2 -SiC-Ti 3 SiC 2 Composites Prepared by Spark Plasma Sintering

Dense TiSi 2 -SiC and TiSi 2 -SiC-Ti 3 SiC 2 composites in which SiC particles in 200-300 nm disperse, were reactively synthesized through spark plasma sintering (SPS) technique using TiC, Si, and C powders in micrometer as starting reactants. The phase constituents and microstructures of the samples were analyzed by X-ray diffraction, field emission scanning electron microscopy and transmission emission microscopy. The hardness, fracture toughness and bending strength of TiSi 2 -SiC and TiSi 2 -SiC-Ti 3 SiC 2 composites were tested at room temperature. The fracture toughness and bending strength of TiSi 2 -SiC-Ti 3 SiC 2 composites reach 5:4 AE 0:3 MPaÁm 1=2 and 700 AE 50 MPa, respectively. The factors leading to the improvement of the mechanical properties were discussed

Low-carbon operation optimization of integrated energy system considering CCS-P2G and multi-market interaction

Integrated energy system is crucial in realizing China’s “dual carbon” targets. Considering the carbon capture based electricity to gas and the interaction of multiple markets, this paper proposes a low-carbon operation optimization method of integrated energy system. In terms of market policy, a coupling trading mechanism for carbon trade and green certificates is established. This approach is intended to delve into the profound significance of utilizing green certificates in carbon emission reduction. In terms of equipment models, the coupling model of carbon capture equipment with coal-fired cogeneration unit, as well as power-to-gas equipment with renewable energy, is con-structed. In addition, this equipment model is introduced into the operation optimization scheduling of the comprehensive energy systems. A low-carbon economic operational strategy is further proposed to minimize the daily operational costs, by which the integrated energy system is eco-nomically, environmental protection optimized. To verify the effectiveness and feasibility of the proposed model, this paper sets up several comparison scenarios and conducts the simulations using GUROBI solver. The results show that the proposed strategy can effectively improve the uptake rate of renewable energy, reduce the carbon emission, improve the operation economy, and realize the complementary incentive effect between markets

Entropy as a Gene‐Like Performance Indicator Promoting Thermoelectric Materials

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138909/1/adma201702712.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138909/2/adma201702712-sup-0001-S1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138909/3/adma201702712_am.pd

Integrated barcode chips for rapid, multiplexed analysis of proteins in microliter quantities of blood

As the tissue that contains the largest representation of the human proteome [1], blood is the most important fluid for clinical diagnostics [2, 3, 4]. However, although changes of plasma protein profiles reflect physiological or pathological conditions associated with many human diseases, only a handful of plasma proteins are routinely used in clinical tests. Reasons for this include the intrinsic complexity of the plasma proteome [1], the heterogeneity of human diseases and the rapid degradation of proteins in sampled blood [5]. We report an integrated microfluidic system, the integrated blood barcode chip that can sensitively sample a large panel of protein biomarkers over broad concentration ranges and within 10 min of sample collection. It enables on-chip blood separation and rapid measurement of a panel of plasma proteins from quantities of whole blood as small as those obtained by a finger prick. Our device holds potential for inexpensive, noninvasive and informative clinical diagnoses, particularly in point-of-care settings

Bacterial community diversity of meltwater runoff and soil in Midre Lovénbreen glacier in Ny-Ålesund, Arctic

Glacial meltwater runoff is a dynamic ecosystem. On the one hand, nutrient concentration changes as it flows from upstream to downstream, and on the other hand, bacterial community structure changes due to its contact with nearby soil during the flow process. We studied meltwater and soil in the Midre Lovénbreen glacier region, to explore changes in bacterial diversity as meltwater flows, and the relationship between meltwater and soil bacterial diversity. As glacial meltwater flows from upstream to downstream, the relative abundance of dominant bacterial groups changes. In addition, we found that during the flowing process, nutrient exchange and bacterial contact had occurred between the meltwater runoff and the soil. As a result, the distribution patterns of some bacteria in the meltwater are very similar to those in the soil. Finally, we combined distance-based redundancy analysis and weighted correlation network analysis to show that NO3 −-N and NO2 −-N are the most two significant factors affecting glacial meltwater and soil, respectively. Our results suggest that in such a close-knit ecosystem, the interaction of glacial meltwater with soil, as well as environmental factors, together determine bacterial community composition