The growing inequality between firms

Globalisation, technological progress and a range of policies and institutions are driving ‘Great Divergences’ in wages and productivity, write Giuseppe Berlingieri, Patrick Blanchenay and Chiara Criscuol

Paper-Based Microfluidic Device with Upconversion Fluorescence Assay

A paper-based microfluidic device with upconversion fluorescence assay (named as UC-μPAD) is proposed. The device is fabricated on a normal office printing sheet with a simple plotting method. Upconversion phosphors (UCPs) tagged with specific probes are spotted to the test zones on the μPAD, followed by the introduction of assay targets. Upconversion fluorescence measurements are directly conducted on the test zones after the completion of the probe-to-target reactions, without any post-treatments. The UC-μPAD features very easy fabrication and operation, simple and fast detection, low cost, and high sensitivity. UC-μPAD is a promising prospect for a clinical point-of-care test

Heat Transfer and Fluidization Characteristics of Lignite in a Pulsation-Assisted Fluidized Bed

To address the problem of low drying efficiency increasing lignite dryer size, a pulsation-assisted fluidized bed with horizontal tube bundles was built for investigating the heat transfer in lignite particles with the goal of enhancing the lignite drying rate by introducing a pulsed flow to increase the heat transfer rate. Results showed that the pulsation-assisted flow increased the heat transfer rates by a maximum of 50–100%. The heat-enhancement effect increased as the gas velocity increased, with 3 and 5 Hz pulsation-assisted flows demonstrating higher heat transfer rates than a 1 Hz flow. Local heat transfer rates showed a maximum value at the tube top for lignite. Simulation was conducted to analyze the details of the lignite particles and bubble movements to explain the heat transfer rate enhancement effect

Establishing Water-Soluble Layered WS₂ Nanosheet as a Platform for Biosensing

Layered WS₂ nanosheet is a kind of two-dimensional (2D) covalent-network solid material with remarkable structural and electronic properties that has attracted increasing interest in recent years. In this work, we propose a one-step sonication-assisted exfoliation method to prepare water-soluble WS₂ nanosheet and demonstrate its application as a biosensing platform. The synthesis route is simple and straightforward. We reveal that single-strand DNA (ssDNA) chains can readily be adsorbed on the nanosheet, leading to complete and fast quenching of a fluorescent dye tagged to the DNA chain. The adsorbed ssDNA is detachable from the nanosheet upon the interaction with other biomolecules, resulting in the restoration of the fluorescence. The 2D WS₂ nanosheet thus acts as an efficient platform for assembling of bioprobes. Because of the extraordinarily high quenching efficiency, which is the synergic result of both excited-state energy transfer and static quenching, the WS₂ platform affords minimal background and high sensitivity. Our attempt will extend the application of this material to biosensing and probing areas

Mechanism of Assembling Isoprenoid Building Blocks 1. Elucidation of the Structural Motifs for Substrate Binding in Geranyl Pyrophosphate Synthase

Terpenes (isoprenoids) represent the most functionally and structurally diverse group of natural products. Terpenes are assembled from two building blocks, isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP or DPP), by prenyltransferases (PTSs). Geranyl pyrophosphate synthase (GPPS) is the enzyme that assembles DPP and IPP in the first step of chain elongation during isoprenoid biosynthesis. The mechanism by which GPPS assembles the terpene precursor remains unknown; elucidating this mechanism will help in development of new technology to generate novel natural product-like scaffolds. With classic and QM/MM MD simulations, an “open-closed” conformation change of the catalytic pocket was observed in the GPPS active site at its large subunit (LSU), and a critical salt bridge between Asp91­(in loop 1) and Lys239­(in loop 2) was identified. The salt bridge is responsible for opening or closing the catalytic pocket. Meanwhile, the small subunit (SSU) regulates the size and shape of the hydrophobic pocket to flexibly host substrates with different shapes and sizes (DPP/GPP/FPP, C₅/C₁₀/C₁₅). Further QM/MM MD simulations were carried out to explore the binding modes for the different substrates catalyzed by GPPS. Our simulations suggest that the key residues (Asp91, Lys239, and Gln156) are good candidates for site-directed mutagenesis and may help in protein engineering

Tandem copies of <i>VVE</i> (or the reverse complement orientation) motif on the strength of GUS activities.

<p>A. The number and orientation of <i>VVE</i> tandems is illustrated (not to scale). <i>VVE</i>, represented with black arrows, is placed upstream of the minimal 35S promoter (−65; black box) to drive <i>uidA</i> (blank box) expression (see “Materials and methods”). B. Quantitative GUS activity analysis of the tandem construction in leaves of 10 d transgenic Arabidopsis seedlings. pFGC-DR and pFGC-MiniGUS were used as positive and negative controls, respectively. GUS activity in pFGC-DR transgenic seedlings was assigned as 100%. GUS activity is replicated three times of each collection of seedlings from independent transgenic lines (indicated in parentheses) per construction. Error bars are standard deviations.</p

The construction and results of the 5′- and 3′- deletions of <i>VVE</i> motif between −1500 and −1324 of the AmidP.

<p>A. Sequence and element site analysis of the <i>VVE</i> motif in the AmidP. 4 nucleotides (grey box) are arbitrarily added to form an <i>Eco</i>RI acting site. Element sites for known transcription factors indicated as arrows are detected by AthaMap web tools (see “Materials and methods”). Vertical dotted line indicated deletion sites. B. Schematic diagram of the chimeric constructs. The numbers above the bars indicate the residual region of the <i>VVE</i> motif after 5′- or 3′- deletions. All the fused constructs are obtained by ligation of the pFGC-MiniGUS and the PCR products precut by <i>Eco</i>RI and <i>Bam</i>HI respectively. C–K. Representative histochemical stained cotyledon demonstrates the strength and specificity of GUS activities in the transgenic Arabidopsis of 5M1 (C), 5M2 (D), 5M3 (E), 5M4 (F), 3M1 (G), 3M2 (H), 3M3 (I), 3M4 (J), and 3M5 (K).</p

Ultrasensitive Photoelectrochemical Biosensing of Multiple Biomarkers on a Single Electrode by a Light Addressing Strategy

Ultrasensitive multiplexed detection of biomarkers on a single electrode is usually a great challenge for electrochemical sensors. Here, a light addressable photoelectrochemical sensor (LAPECS) for the sensitive detection of multiple DNA biomarkers on a single electrode was reported. The sensor was constructed through four steps: (1) immobilization of capture DNA (C-DNA) of different targets on different areas of a single large-sized gold film electrode, (2) recognition of each target DNA (T-DNA) and the corresponding biotin-labeled probe DNA (P-DNA) through hybridization, (3) reaction of the biotin-labeled probe DNA with a streptavidin-labeled all-carbon PEC bioprobe, and (4) PEC detection of multiple DNA targets one by one via a light addressing strategy. Through this principle, the LAPECS can achieve ultrasensitive detection of three DNA sequences related to hepatitis B (HBV), hepatitis C (HCV) and human immunodeficiency (HIV) viruses with a similar wide calibration range of 1.0 pM ∼ 0.01 μM and a low detection limit of 0.7 pM by using one kind of PEC bioprobe. Moreover, the detection throughput of LAPECS may be conveniently expanded by simply enlarging the size of the substrate electrode or reducing the size of the sensing arrays and the light beam. The present work thus demonstrates the promising applications of LAPECS in developing portable, sensitive, high-throughput, and cost-effective biosensing systems

The AmidP drives the GUS expression in the vascular vein of leaves resembling a pattern of the sink-to-source transition.

<p>A. GUS expression is detected in cotyledons and the distal tip of young leaves of 10-d seedlings. B. The AmidP drives expression in the germinating seed joint of above- and under-ground part. C–D. GUS activity is detected in sepals of flowers (C), as shown in an amplified flower indicated with a red arrow (D). E–J. X-Gluc staining is detected throughout the vascular veins of a cotyledon (E), expanded source leaves (F, G, and H) and progresses basipetally down transition leaves (I and J).</p

Various primers used in this experiment.

<p>Various primers used in this experiment.</p