Ranking sectors and countries within global value chains is of paramount importance to estimate risks and forecast growth in large economies. However, this task is often non-trivial due to the lack of complete and accurate information on the flows of money and goods between sectors and countries, which are encoded in input-output (I-O) tables. In this work, we show that an accurate estimation of the role played by sectors and countries in supply chain networks can be achieved without full knowledge of the I-O tables, but only relying on local and aggregate information, e.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
October 2024
The Katz centrality of a node in a complex network is a measure of the node's importance as far as the flow of information across the network is concerned. For ensembles of locally tree-like undirected random graphs, this observable is a random variable. Its full probability distribution is of interest but difficult to handle analytically because of its "global" character and its definition in terms of a matrix inverse.
View Article and Find Full Text PDFPlasmonic nanoparticles play an important role in applications for chemical sensing, catalysis, medicine, and biosensing. The localized surface plasmon resonance (LSPR) of a nanoparticle is determined by factors such as size, shape, and the local dielectric environment. Here, we report a simple colloidal synthesis method to create core-shell plasmonic nanoparticles with a gold core and a copper oxide (CuO) shell.
View Article and Find Full Text PDFTunable porous composite materials to control metal and metal oxide functionalization, conductivity, pore structure, electrolyte mass transport, mechanical strength, specific surface area, and magneto-responsiveness are critical for a broad range of energy storage, catalysis, and sensing applications. Biotemplated transition metal composite aerogels present a materials approach to address this need. To demonstrate a solution-based synthesis method to develop cobalt and cobalt oxide aerogels for high surface area multifunctional energy storage electrodes, carboxymethyl cellulose nanofibers (CNF) and alginate biopolymers were mixed to form hydrogels to serve as biotemplates for cobalt nanoparticle formation via the chemical reduction of cobalt salt solutions.
View Article and Find Full Text PDFFluorescent ligands are imperative to many facets of chemical biology and medicinal chemistry. Herein, we report the syntheses of two fluorescent melatonin-based derivatives as potential ligands of melatonin receptors. The two compounds, namely, 4-cyano and 4-formyl melatonin (4CN-MLT and 4CHO-MLT, respectively), which differ from melatonin by only two/three atoms that are very compact in size, were prepared using the selective C3-alkylation of indoles with -acetyl ethanolamines involving the "borrowing hydrogen" strategy.
View Article and Find Full Text PDFThe standard primitives of quantum computing include deterministic unitary entangling gates, which are not natural operations in many systems including photonics. Here, we present fusion-based quantum computation, a model for fault tolerant quantum computing constructed from physical primitives readily accessible in photonic systems. These are entangling measurements, called fusions, which are performed on the qubits of small constant sized entangled resource states.
View Article and Find Full Text PDFspindle-shaped virus 1 (SSV1) was one of the first viruses identified in the archaeal kingdom. Originally isolated from a Japanese species of back in 1984, it has been extensively used as a model system for genomic, transcriptomic, and proteomic studies, as well as to unveil the molecular mechanisms governing the host-virus interaction. The purpose of this mini review is to supply a compendium of four decades of research on the SSV1 virus.
View Article and Find Full Text PDFThe growing importance of structurally diverse and functionalized enantiomerically pure unnatural amino acids in the design of drugs, including peptides, has stimulated the development of new synthetic methods. This study reports the challenging direct asymmetric alkylation of cyclic ketones with dehydroalanine derivatives via a conjugate addition reaction for the synthesis of enantiopure ketone-based α-unnatural amino acids. The key to success was the design of a bifunctional primary amine-thiourea catalyst that combines H-bond-directing activation and enamine catalysis.
View Article and Find Full Text PDFGeothermal springs are rich in various metal ions due to the interaction between rock and water that takes place in the deep aquifer. Moreover, due to seasonality variation in pH and temperature, fluctuation in element composition is periodically observed within these extreme environments, influencing the environmental microbial communities. Extremophilic microorganisms that thrive in volcanic thermal vents have developed resistance mechanisms to handle several metal ions present in the environment, thus taking part to complex metal biogeochemical cycles.
View Article and Find Full Text PDFBackground: Oral immunotherapy (OIT) is an emerging treatment for cow's milk protein (CMP) allergy in children. The mechanisms driving tolerance following OIT are not well understood. Regulatory T cells (T) cells are key inhibitors of allergic responses and promoters of allergen-specific tolerance.
View Article and Find Full Text PDFArsenic detoxification systems can be found in a wide range of organisms, from bacteria to humans. In a previous study, we discovered an arsenic-responsive transcriptional regulator in the thermophilic bacterium Thermus thermophilus HB27 (SmtB). Here, we characterize the arsenic resistance system of T.
View Article and Find Full Text PDFThe MT -selective melatonin receptor ligand UCM765 (N-(2-((3-methoxyphenyl)(phenyl)amino)ethyl)acetamide), showed interesting sleep inducing, analgesic and anxiolytic properties in rodents, but suffers from low water solubility and modest metabolic stability. To overcome these limitations, different strategies were investigated, including modification of metabolically liable sites, introduction of hydrophilic substituents and design of more basic derivatives. Thermodynamic solubility, microsomal stability and lipophilicity of new compounds were experimentally evaluated, together with their MT and MT binding affinities.
View Article and Find Full Text PDFExtreme environments are excellent places to find microorganisms capable of tolerating extreme temperature, pH, salinity pressure, and elevated concentration of heavy metals and other toxic compounds. In the last decades, extremophilic microorganisms have been extensively studied since they can be applied in several fields of biotechnology along with their enzymes. In this context, the characterization of heavy metal resistance determinants in thermophilic microorganisms is the starting point for the development of new biosystems and bioprocesses for environmental monitoring and remediation.
View Article and Find Full Text PDFBackground: The spore-forming lactic acid bacterium Bacillus coagulans MA-13 has been isolated from canned beans manufacturing and successfully employed for the sustainable production of lactic acid from lignocellulosic biomass. Among lactic acid bacteria, B. coagulans strains are generally recognized as safe (GRAS) for human consumption.
View Article and Find Full Text PDFPowder vaporization is a common method for the generation of large-area, single-crystal, two-dimensional molybdenum disulfide. While commonly employed as a growth method, the fundamental molecular mechanisms are not well understood. Recent ab initio analyses have shown that molybdenum oxysulfide rings play a key role in the sulfurization of molybdenum trioxide from elemental sulfur.
View Article and Find Full Text PDFWe propose a modelling framework for the optimal selection of crypto assets. We assume that crypto assets can be described according to two features: (technological) and (governance). We simulate optimal selection decisions of investors, being driven by (i) their attitudes towards assets' features, (ii) information about the adoption trends, and (iii) expected future economic benefits of adoption.
View Article and Find Full Text PDF-anilinoethylamides are a class of melatoninergic agents with the aniline portion mimicking the indole ring of the natural ligand and the ethylamide chain reproducing that of melatonin. The simplest compound in this class, -{2-[(3-methoxyphenyl)methylamino]ethyl}acetamide (UCM793), has nanomolar binding affinity for MT and MT membrane receptors. To explore the effect of chain conformation on receptor binding, a methyl group was inserted on the methylene alpha or beta to the amide nitrogen and conformational equilibria were investigated by NMR spectroscopy and molecular dynamics simulations.
View Article and Find Full Text PDFAs highlighted by European statistics, the employment of donor oocytes is a growing option for women who cannot make use of their own gametes. As the potential recipients are continuously increasing in number, a donor programme which satisfies this demand is mandatory. Improvements in cryopreservation techniques, like oocyte and embryo vitrification, have led to the overcoming of the sequence of stimulation-retrieval-transfer both from a spatial and a temporal point of view, with the development of cryobanks of oocytes permitting crossborder donation.
View Article and Find Full Text PDFTo fight reactive oxygen species (ROS) produced by both the metabolism and strongly oxidative habitats, hyperthermophilic archaea are equipped with an array of antioxidant enzymes whose role is to protect the biological macromolecules from oxidative damage. The most common ROS, such as superoxide radical (O) and hydrogen peroxide (HO), are scavenged by superoxide dismutase, peroxiredoxins, and catalase. These enzymes, together with thioredoxin, protein disulfide oxidoreductase, and thioredoxin reductase, which are involved in redox homeostasis, represent the core of the antioxidant system.
View Article and Find Full Text PDFChymotrypsinogen, when reduced and taken to its molten globule-like conformation, displays a single cysteine with an unusual kinetic propensity toward oxidized glutathione (GSSG) and other organic thiol reagents. A single residue, identified by mass spectrometry like Cys1, reacts with GSSG about 1400 times faster than an unperturbed protein cysteine. A reversible protein-GSSG complex and a low pK (8.
View Article and Find Full Text PDFThe synthesis of high surface area porous noble metal nanomaterials generally relies on time consuming coalescence of pre-formed nanoparticles, followed by rinsing and supercritical drying steps, often resulting in mechanically fragile materials. Here, a method to synthesize nanostructured porous platinum-based macrotubes and macrobeams with a square cross section from insoluble salt needle templates is presented. The combination of oppositely charged platinum, palladium, and copper square planar ions results in the rapid formation of insoluble salt needles.
View Article and Find Full Text PDFViruses of hyperthermophilic archaea represent one of the least understood parts of the virosphere, showing little genomic and morphological similarity to viruses of bacteria or eukaryotes. Here, we investigated virus diversity in the active sulfurous fields of the Campi Flegrei volcano in Pozzuoli, Italy. Virus-like particles displaying eight different morphotypes, including lemon-shaped, droplet-shaped and bottle-shaped virions, were observed and five new archaeal viruses proposed to belong to families Rudiviridae, Globuloviridae and Tristromaviridae were isolated and characterized.
View Article and Find Full Text PDFMicroorganisms thriving in hot springs and hydrothermally active volcanic areas are dynamically involved in heavy-metal biogeochemical cycles; they have developed peculiar resistance systems to cope with such metals which nowadays can be considered among the most permanent and toxic pollutants for humans and the environment. For this reason, their exploitation is functional to unravel mechanisms of toxic-metal detoxification and to address bioremediation of heavy-metal pollution with eco-sustainable approaches. In this work, we isolated a novel strain of the thermophilic bacterium from the solfataric mud pool in Pisciarelli, a well-known hydrothermally active zone of the Campi Flegrei volcano located near Naples in Italy, and characterized it by ribotyping, 16S rRNA sequencing and mass spectrometry analyses.
View Article and Find Full Text PDFTo fight oxidative damage due to reactive oxygen species (ROS), cells are equipped of different enzymes, among which Peroxiredoxins (Prxs) (EC 1.11.1.
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