Rethinking infrastructure financing for Southeast Asia in the post-pandemic era

This report analyzes how the pandemic has impacted investment in infrastructure in Southeast Asia and assesses how infrastructure development can help drive economic recovery and support sustainable growth. Calculating $1.7 trillion will be spent each year on infrastructure in Asia, it shows how the pandemic hit public financing and altered investor appetites. It highlights the growing need for public–private partnerships and outlines financing models, risks, and trends. It recommends governments create an enabling environment to mitigate investor risk, conduct feasibility studies, and build a pipeline of bankable projects to help finance the infrastructure they need for a resilient future

Electrical release of dopamine and levodopa mediated by amphiphilic \u3b2-cyclodextrins immobilized on polycrystalline gold

Vesicles of cationic amphiphilic \u3b2-cyclodextrins have been immobilized on polycrystalline gold by exploiting the chemical affinity between their amino groups and Au atoms. The presence of cyclodextrins has been widely investigated by means of AFM, XPS, kelvin probe and electrochemical measurements. This multi-functional coating confers distinct electrochemical features such as pH-dependent behavior and partial/total blocking properties towards electro-active species. The host-guest properties of \u3b2-cyclodextrins have been successfully exploited in order to trap drugs, like dopamine and levodopa. The further release of these drugs was successfully achieved by providing specific electrical stimuli. This proof-of-concept led us to fabricate an electronic device (i.e. an organic transistor) capable of dispensing both dopamine and levodopa in aqueous solution

How to Turn an Electron Transfer Protein into a Redox Enzyme for Biosensing

Cytochrome c is a small globular protein whose main physiological role is to shuttle electrons within the mitochondrial electron transport chain. This protein has been widely investigated, especially as a paradigmatic system for understanding the fundamental aspects of biological electron transfer and protein folding. Nevertheless, cytochrome c can also be endowed with a non-native catalytic activity and be immobilized on an electrode surface for the development of third generation biosensors. Here, an overview is offered of the most significant examples of such a functional transformation, carried out by either point mutation(s) or controlled unfolding. The latter can be induced chemically or upon protein immobilization on hydrophobic self-assembled monolayers. We critically discuss the potential held by these systems as core constituents of amperometric biosensors, along with the issues that need to be addressed to optimize their applicability and response

Adsorbing surface strongly influences the pseudoperoxidase and nitrite reductase activity of electrode-bound yeast cytochrome c. The effect of hydrophobic immobilization

The Met80Ala and Met80Ala/Tyr67Ala variants of S. cerevisiae iso-1 cytochrome c (ycc) and their adducts with cardiolipin immobilized onto a gold electrode coated with a hydrophobic self-assembled monolayer (SAM) of decane-1-thiol were studied through cyclic voltammetry and surface-enhanced resonance Raman spectroscopy (SERRS). The electroactive species - containing a six-coordinate His/His axially ligated heme and a five-coordinate His/- heme stable in the oxidized and reduced state, respectively - and the pseudoperoxidase activity match those found previously for the wt species and are only slightly affected by CL binding. Most importantly, the reduced His/- ligated form of these variants is able to catalytically reduce the nitrite ion, while electrode-immobilized wt ycc and other His/Met heme ligated variants under a variety of conditions are not. Besides the pseudoperoxidase and nitrite reductase functions, which are the most physiologically relevant abilities of these constructs, also axial heme ligation and the equilibria between conformers are strongly affected by the nature - hydrophobic vs. electrostatic - of the non-covalent interactions determining protein immobilization. Also affected are the catalytic activity changes induced by a given mutation as well as those due to partial unfolding due to CL binding. It follows that under the same solution conditions the structural and functional properties of immobilized ycc are surface-specific and therefore cannot be transferred from an immobilized system to another involving different interfacial protein-SAM interactions

Surface Immobilized His-tagged Azurin as a Model Interface for the Investigation of Vectorial Electron Transfer in Biological Systems

A model system for the electrochemical investigation of vectorial electron transfer in biological systems was designed, assembled and characterized. Gold electrodes, functionalized with a -OCH3 terminated, aromatic self-assembled monolayer, were used as a substrate for the adsorption of variants of copper- containing, redox metalloprotein azurin. The engineered azurin bears a polyhistidine tag at its C-terminus. Thanks to the presence of the solvent exposed tag, which chelates Cu2+ ions in solution, we introduced an exogenous redox centre. The different reduction potentials of the two redox centres and their positioning with respect to the surface are such that electron transfer from the exogenous copper centre and the electrode is mediated by the native azurin active site, closely paralleling electron transfer processes in naturally occurring multicentre metalloprotein

The Substrate is a pH-Controlled Second Gate of Electrolyte-Gated Organic Field-Effect Transistor

Electrolyte-gated organic field-effect transistors (EGOFETs), based on ultra-thin pentacene films on quartz, were operated with electrolyte solutions whose pH was systematically changed. Transistor parameters exhibit non-monotonic variation vs pH, which cannot be accounted for by capacitive coupling through the Debye-Helmholtz layer. The data were fitted with an analytical model of the accumulated charge in the EGOFET where Langmuir adsorption was introduced to describe the (pH-dependent) charge build-up at the quartz surface. The model provides an excellent fit to the threshold voltage and transfer characteristics as a function of pH, which demonstrates that quartz acts as a second gate controlled by pH, and is mostly effective at neutral or alkaline pH. The effective capacitance of the device is always greater than the capacitance of the electrolyte, thus highlighting the role of the substrate as an important active element for amplification of the transistor response

Harnessing Selectivity and Sensitivity in Ion Sensing via Supramolecular Recognition: A 3D Hybrid Gold Nanoparticle Network Chemiresistor

The monitoring of K+ in saliva, blood, urine, or sweat represents a future powerful alternative diagnostic tool to prevent various diseases. However, several K+ sensors are unable to meet the requirements for the development of point‐of‐care (POC) sensors. To tackle this grand‐challenge, the fabrication of chemiresistors (CRs) based on 3D networks of Au nanoparticles covalently bridged by ad‐hoc supramolecular receptors for K+, namely dithiomethylene dibenzo‐18‐crown‐6 ether is reported here. A multi‐technique characterization allows optimizing a new protocol for fabricating high‐performing CRs for real‐time monitoring of K+ in complex aqueous environments. The sensor shows exceptional figures of merit: i) linear sensitivity in the 10^–3 to 10^–6 m concentration range; ii) high selectivity to K+ in presence of interfering cations (Na+, Ca2+, and Mg2+); iii) high shelf‐life stability (>45 days); iv) reversibility of K+ binding and release; v) successful device integration into microfluidic systems for real‐time monitoring; vi) fast response and recovery times (<18 s), and v) K+ detection in artificial saliva. All these characteristics make the supramolecular CRs a potential tool for future applications as POC devices, especially for health monitoring where the determination of K+ in saliva is pivotal for the early diagnosis of diseases

Immune Response to Mycobacterium tuberculosis Infection in the Parietal Pleura of Patients with Tuberculous Pleurisy

The T lymphocyte-mediated immune response to Mycobacterium tuberculosis infection in the parietal pleura of patients with tuberculous pleurisy is unknown. The aim of this study was to investigate the immune response in the parietal pleura of tuberculous pleurisy compared with nonspecific pleuritis. We have measured the numbers of inflammatory cells particularly T-cell subsets (Th1/Th2/Th17/Treg cells) in biopsies of parietal pleura obtained from 14 subjects with proven tuberculous pleurisy compared with a control group of 12 subjects with nonspecific pleuritis. The number of CD3+, CD4+ and CCR4+ cells and the expression of RORC2 mRNA were significantly increased in the tuberculous pleurisy patients compared with the nonspecific pleuritis subjects. The number of toluidine blue+ cells, tryptase+ cells and GATA-3+ cells was significantly decreased in the parietal pleura of patients with tuberculous pleurisy compared with the control group of nonspecific pleuritis subjects. Logistic regression with receiver operator characteristic (ROC) analysis for the three single markers was performed and showed a better performance for GATA-3 with a sensitivity of 75%, a specificity of 100% and an AUC of 0.88. There was no significant difference between the two groups of subjects in the number of CD8, CD68, neutrophil elastase, interferon (IFN)-γ, STAT4, T-bet, CCR5, CXCR3, CRTH2, STAT6 and FOXP3 positive cells. Elevated CD3, CD4, CCR4 and Th17 cells and decreased mast cells and GATA-3+ cells in the parietal pleura distinguish patients with untreated tuberculous pleurisy from those with nonspecific pleuritis

High performing solution-coated electrolyte-gated organic fieldeffect transistors for aqueous media operation

Since the first demonstration, the electrolyte-gated organic field-effect transistors (EGOFETs) have immediately gained much attention for the development of cutting-edge technology and they are expected to have a strong impact in the field of (bio-)sensors. However EGOFETs directly expose their active material towards the aqueous media, hence a limited library of organic semiconductors is actually suitable. By using two mostly unexplored strategies in EGOFETs such as blended materials together with a printing technique, we have successfully widened this library. Our benchmarks were 6,13-bis(triisopropylsilylethynyl)pentacene and 2,8-difluoro-5,11-bis(triethylsilylethynyl) anthradithiophene (diF-TES-ADT), which have been firstly blended with polystyrene and secondly deposited by means of the bar-assisted meniscus shearing (BAMS) technique. Our approach yielded thin films (i.e. no thicker than 30 nm) suitable for organic electronics and stable in liquid environment. Up to date, these EGOFETs show unprecedented performances. Furthermore, an extremely harsh environment, like NaCl 1M, has been used in order to test the limit of operability of these electronic devices. Albeit an electrical worsening is observed, our devices can operate under different electrical stresses within the time frame of hours up to a week. In conclusion, our approach turns out to be a powerful tool for the EGOFET manufacturing.The authors thank the ERC StG 2012–306826 e-GAMES project, the Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), the DGI (Spain) project BE-WELL CTQ2013-40480-R, the Generalitat de Catalunya (2014-SGR-17) and the Spanish Ministry of Economy and Competitiveness, through the ‘Severo Ochoa’ Programme for Centres of Excellence in R&D (SEV- 2015-0496). Q. Z. acknowledges the China Scholarship Council, the National Natural Science Foundation (NSF) of China (Grant No. 11404266) and the Fundamental Research Funds for the Central Universities of China (Grant No. XDJK2014C081). Q. Z. And I. T. are enrolled in the Materials Science PhD Program of Universitat Autònoma de Barcelona. F.L. gratefully acknowledges the “Juan de la Cierva” programme. The research leading to these results has received funding from the People Programme (Marie Curie Actions) of the Seventh Framework Programme of the European Union (FP7/2007–2013) under REA grant agreement no.600388 (TECNIOSpring programme), and from the Agency for Business Competitiveness of the Government of Catalonia, ACCIÓ. The authors thank Dr. D. Gutierrez and Dr. S. Galindo for their assistance with the switching speed measurements.Peer reviewe

Impact investing as a societal refocus of venture capital: the perspective of mature economies

La strada dell'impact investing può rappresentare un cambiamento radicale della logica di intervento del venture capital, individuando sia nuovi spazi di investimento che modalità originali di mitigazione dle rischio