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Using a multi-orifice cylindrical silo, the average flow rates Q1 and QN through one and N orifices, respectively, were first measured for the discharge of water or dry grains and then for the mixture. As expected, Q N = N Q 1 for monophasic discharges. Nevertheless, for the mixture, Q N ≪ N Q 1 , and the effect becomes more notorious as N augments and when the grain size is decreased. A simplified continuum model of a flow through a dynamic porous medium, with hydrodynamic resistance that increases with N, is used to reproduce the experimental results. Additional analysis in a two-dimensional cell reveals interacting parabolic flow profiles of the immersed particles close to the orifices, with a reduction in the average velocities when N is increased, which helps to understand the non-additivity of the total flow rate. [ABSTRACT FROM AUTHOR]

Enzyme driven oxidations catalyzed by alcohol dehydrogenases rely on the in situ NAD(P)+ regeneration. A wide variety of chemoenzymatic and fully enzymatic methods have been reported over the last 30 years to integrate the cofactor regeneration in biocatalytic oxidations. However, the majority of examples are limited to homogeneous systems where the reuse of both enzymes and chemical catalysts are challenging. In this work, we co‐immobilize an alcohol dehydrogenase from Bacillus stearothermophilus with a flavin derivative (FMN), which performs as an organocatalyst that oxidizes NADH back to NAD+. This latter oxidized cofactor is sequentially utilized by the dehydrogenase to oxidize 1,ω‐diols. Remarkably, the immobilization chemistry of FMN determines its efficiency to oxidize NADH and, unlike in its free state, the immobilized FMN can recycle NAD+ in dark. This is possible because the support where both enzyme and FMN are immobilized also captures NADH, making the electron transfer from the substrates to the cofactors more efficient. This work illustrates how the co‐immobilization and confinement of bio and chemical catalysts on solid materials (heterogeneous phase) enable chemoenzymatic cascades that are precluded in solution (homogeneous phase). [ABSTRACT FROM AUTHOR]

The tourist destination Santiago de Cuba is characterized by the development of the traditional modality of sun and beach, nature, history, heritage, as well as cultural and city tourism (Ministry of Tourism, 2019). The latter is one of the main sources of motivation for international tourists who arrive in the city. However, there is no differentiating proposal for the destination in relation to other destinations in the region, by offering events and cultural itineraries, which need to be rethought from the sociocultural values that characterize it as a welcoming destination given the idiosyncrasy of its people. The markedly Caribbean cultural expressions; intangible heritage values that make it stand out among the destinations of the eastern region and the rest of the country’s tourist cities. In this way, the bases are offered to promote the work of integration of the social actors linked to tourism and consequently, the weighting of the attributes of the destination. [ABSTRACT FROM AUTHOR]

A poly(thiophene acetic acid)/Au/poly(methylene blue) nanostructured interface was electrochemically assembled step-by-step on screen-printed carbon electrodes (SPCE) for label-free detection of p53 protein. The initial electrical conductive properties of the polymeric interface were increased with an additional layer of poly(methylene blue) electropolymerized in the presence of gold nanoparticles. The nano-immunosensing architecture was prepared by covalent immobilization of anti-p53 antibodies as bioreceptors through the poly(thiophene acetic acid) moieties. The nano-immunosensor assembly was extensively characterized by ultraviolet–visible spectrophotometry, dynamic and electrophoretic light scattering, scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, atomic force microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. Under optimal conditions, p53 was specifically and selectively detected by square wave voltammetry in a linear range between 1 and 100 ng mL−1 with a limit of detection of 0.65 ng mL−1. In addition, the electrochemical nano-immunosensor detected p53 in spiked human serum samples and colorectal cancer cell lysates, and the results were validated with a standard spectrophotometric method using a paired samples t test, which did not exhibit significant differences between both methods. The resultant p53 nano-immunosensor is simple to assemble, robust, and has the potential for point-of-care biomarker detection applications. [ABSTRACT FROM AUTHOR]

A label-free nanoimmunosensor is reported based on p53/CeO2/PEDOT nanobiocomposite-decorated screen-printed gold electrodes (SPAuE) for the electrochemical detection of anti-p53 autoantibodies. CeO2 nanoparticles (NPs) were synthesized and stabilized with cyanopropyltriethoxysilane by a soft chemistry method. The nanoimmunosensing architecture was prepared by in situ electropolymerization of 3,4-ethylenedioxythiophene (EDOT) on SPAuE in the presence of CeO2 NPs. The CeO2 NPs and Ce/PEDOT/SPAuE were characterized by scanning and transmission electron microscopy, dynamic and electrophoretic light scattering, ultraviolet–visible spectrophotometry, X-ray diffraction, Fourier-transform infrared spectroscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. Ce/PEDOT/SPAuE was biofunctionalized with p53 antigen by covalent bonding for the label-free determination of anti-p53 autoantibodies by differential pulse voltammetry. The nanobiocomposite-based nanoimmunosensor detected anti-p53 autoantibodies in a linear range from 10 to 1000 pg mL−1, with a limit of detection (LOD) of 3.2 pg mL−1. The nanoimmunosensor offered high specificity, selectivity, and long-term storage stability with great potential to detect anti-p53 autoantibodies in serum samples. Overall, incorporating organo-functional nanoparticles into polymeric matrices can provide a simple-to-assemble, rapid, and ultrasensitive approach for on-site screening of anti-p53 autoantibodies and other disease-related biomarkers with low sample volumes. [ABSTRACT FROM AUTHOR]

Ethanol is the main biofuel produced by fermentation route and the search for new feedstocks to produce fuel ethanol is still a great challenge. This work aims to compare the ethanol production from a new irrigated rice cultivar BRS AG to the conventional cultivar BRS PAMPA applied in Brazil. Six different commercial strains of Saccharomyces cerevisiae (BG-1, CAT-1, FT-858, JP-1, PE-2, and SA-1) were applied in fermentation reactions. Fermentations performed with BRS PAMPA rice revealed that the highest yields were achieved with strain SA-1, corresponding to 93.0% of the theoretical maximum and final ethanol concentration of 58.92 g L−1, and with CAT-1, a yield of 92.7% and final ethanol concentration of 58.93 g L−1. For the fermentations with BRS AG rice, the highest yields were obtained with strain FT-858, exhibiting a 89.6% yield and final ethanol concentration of 62.45 g L−1, and with CAT-1, 87.9% yield and final ethanol concentration of 61.25 g L−1 were achieved. The most appropriate microorganism for ethanol production using BRS PAMPA rice and BRS AG rice was CAT-1. Comparatively, the ethanol yield and productivity using BRS AG were higher than those observed for BRS PAMPA for all strains, except for PE-2 and SA-1 that led to very similar results. The experimental results showed that the giant rice BRS AG is an excellent feedstock for fuel ethanol production in lowland fields. [ABSTRACT FROM AUTHOR]

Bananas are among the most produced fruits globally, and their industry generates substantial amounts of peels, which are currently underutilized. Therefore, a simple process was proposed to fully convert banana peel powder (BPP) into bioplastic films using mild pretreatments. The influence of the following variables on film performance was investigated: the type of BPP (unblanched versus blanched), the pretreatment solvent (water – i.e., hydrothermal pretreatment, HTP – or sulfuric acid solution – i.e., dilute acid pretreatment, DAP), and the addition or not of carboxymethyl cellulose (CMC) in the films. The tensile properties of the bioplastics were primarily affected by the presence of CMC, with the films containing 20 wt% of this biopolymer achieving a tensile strength up to 16 MPa. The water vapor permeability was not influenced by any of the studied variables. In contrast, the water contact angle was primarily affected by the pretreatment employed , with all films prepared by HTP displaying a hydrophobic surface. The UV-shielding properties of the materials were mainly influenced by the type of BPP, and all films blocked at least 98% of UV radiation. The antioxidant activity was influenced primarily by the type of BPP, as blanching banana peels helped preserve it. These films are, therefore, promising materials for active food packaging applications, which could contribute to a transition toward a circular bioeconomy. [Display omitted] • Bulk banana peels were fast pretreated to produce bioplastic films. • Incorporating carboxymethyl cellulose enhanced the tensile film properties. • Banana peel films exhibited excellent UV-shielding properties. • Boiling banana peels in citric acid solution prevented loss of antioxidant activity. • Antioxidant activity remained strong in banana peel bioplastic films. [ABSTRACT FROM AUTHOR]

Precision medicine has potentialized with cutting-edge analytical tools based on electrochemical nanobiosensors as an emerging strategy to personalize diagnosing and treating complex diseases such as colorectal cancer (CRC). These nanobiosensors are robust enough solutions that provide rapid and specific readouts for detecting molecular fingerprints, thereby driving personalized healthcare. Improvements in stability, sensitivity, multiplexing, digitalization, automatic data analysis, and the incorporation of low-cost (nano)materials with simple fabrication methods are crucial for introducing these devices into the market. They offer versatile miniaturization and integration into portable point-of-care diagnostic devices, redefining the analytical landscape. This review discusses the principles of CRC precision medicine, exploring smart data from electrochemical nanobiosensing devices and examining their potential for integration into portable and autonomous systems, and massive diagnostic testing analyzed by big data analytics. It highlights CRC biomarkers detection at different molecular levels and disease monitoring at different stages, underlining the need to address the disease comprehensively. [Display omitted] • The potential of precision medicine in the context of colorectal cancer (CRC). • Electrochemical nanobiosensors as a tool for the identification of molecular fingerprints. • Disruptive technologies for the patient stratification of CRC diagnosis and monitoring. • Integration of miniaturized platforms for automated data analysis and decision-making. • Challenges and perspectives on CRC precision medicine. [ABSTRACT FROM AUTHOR]

This article proposes outcomes for the extension project referred as 'the communication for social change in the community education of the armed conflict victim associations in the municipality of La Playa Belen, Norte de Santander, which aimed to develop communicative strategies for peace building, resilience as well as community education for these armed conflict victim associations in this area known as Catatumbo in Colombia. This research has been based on a qualitative methodology and research-action model, by using information collection techniques such as literature review, focus groups and seni-structured interviews through which an updated diagnostics could be carried out on the socio-economic conditions of the associations settled in this municipality in order to develop strategic actions which allowed to create a scenario for peace and social change. Some of the most relevant results have shown that these social groups need to be educated on a steady basis on different topics such as leadership, team work, community self-management, community organization, citizen participation, and community project or proposition formulation to come up with socio-economic propositions as solution alternatives for the problems which have been identified as a result of the armed conflict that have affected their lives in addition to both physical and symbolic reparation which allow to rebuild governmental trust, social fabric and also the realization of a peaceful territory. [ABSTRACT FROM AUTHOR]

To evaluate the use of ultrasound for identifying the site for needle puncture and to determine the depth to the epidural space in obese dogs. Prospective study in dogs undergoing elective orthopedic surgery. A group of seven obese Labrador male dogs aged 6.93 ± 2.56 years and weighing 46.5 ± 4.1 kg (mean ± standard deviation). The anesthetic protocol for these dogs included epidural anesthesia. With the dogs anesthetized and positioned in sternal recumbency with the pelvic limbs flexed forward, ultrasound imaging was used to locate the lumbosacral intervertebral space. Intersection of dorsal and transverse lines about the probe identified the point of needle insertion. A 17 gauge, 8.9 cm Tuohy needle was inserted perpendicularly through the skin and advanced to the lumbosacral intervertebral space. The number of puncture attempts was recorded and needle depth was compared with skin to ligamentum flavum distance. Epidural injection was performed in all dogs at the first attempt of needle insertion. The distance from skin to epidural space was 5.95 ± 0.62 cm measured by ultrasound and 5.89 ± 0.64 cm measured with the Tuohy needle. These measurements were not different (p = 0.26). A highly significant correlation coefficient of 0.966 between measurement techniques was obtained (p < 0.001). Ultrasound imaging identified the point of needle insertion for lumbosacral epidural injection in seven obese dogs. The results indicate that ultrasound can be used to locate the lumbosacral intervertebral space and identify an appropriate point for needle insertion to perform epidural injection. [ABSTRACT FROM AUTHOR]

Nanoparticles of Ce1−xPrxO2 (X: 0.6 and 0.8), were synthesized by the combustion method using citric acid as chelating and fuel agent. The X‐ray diffraction patterns and Rietveld refinements confirm that samples shown as a single phase in a cubic fluorite structure, with an increase in the lattice parameter as a function of Pr concentration. The crystallite size domains obtained by the Scherrer formula, confirm values around 10 and 37 nm. The scanning electron microscopy images, show that the solids are composed of dense heterogeneous aggregates. The X‐ray photoelectron spectroscopy, reveals that oxides are composed of cerium and praseodymium cations in oxidation states 4+ and 3+ respectively. The TPR‐H2 profiles indicate that cerium and praseodymium cations present in the obtained systems are completely reduced to Ce3+ and Pr3+ at temperatures above 790°C. The impedance spectroscopy data at room temperature showed that the conduction processes for the two systems take place at the grain boundaries. The Ce0.2Pr0.8O2 system offer lower resistance, due to the high amount of Pr3+ ions inserted in the structure and the high amount of oxygen vacancies formed in the synthesis process. [ABSTRACT FROM AUTHOR]

The present study evaluated the alterations of the oxidative stress markers in adult dogs fed with high levels of PUFA from the mixture of soybean oil enriched with docosahexaenoic acid (DHA) and supplemented with a natural algae-based antioxidant (AOX). Twelve healthy adult (2 years old) Beagle dogs (6 males and 6 females, 11.20 ± 1.92 kg BW), were distributed in 2 completely randomized blocks design and fed with 4 experimental diets coated with 2 lipid sources: saturated (13% bovine tallow) or unsaturated (13% soybean oil enriched with DHA), supplemented or not with 500 mg of AOX for 4 wk, intercalated with a 4-wk adaptation period. Blood samples were collected on days 0, 15, and 30 of each block. Glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), sulfhydryl group (SH), protein carbonylation, thiobarbituric acid reactive substances (TBARS), and total reactive antioxidant potential (TRAP) were evaluated in the serum, while GSH-Px, SOD, glutathione S-transferase (GST), catalase (CAT), SH, and TBARS were measured in erythrocytes. There was no significant difference in most of the oxidative markers evaluated. In contrast, GST activity in erythrocytes was greater in the animals that consumed the diets coated with bovine tallow compared to dogs that consumed diets coated with soybean oil enriched with DHA (P < 0.05). Serum from dogs fed on diets supplemented with AOX presented greater TRAP values (P < 0.05). These data demonstrate that the concentrations of unsaturated fatty acids (UNS) used in the diets for dogs were not sufficient to cause large changes in the oxidative status. It was not possible to evaluate the efficiency of the natural antioxidant in maintaining the oxidative balance of the animals as it appears that the oxidative status of the dogs was not challenged by the unsaturated diets. Our findings also suggest that dogs, as descendants from carrion carnivores, may have some natural protection against oxidation. [ABSTRACT FROM AUTHOR]

We experimentally studied the ordering process of a slightly tilted two-dimensional system of millimeter-sized cubes, by annealing the system using vibration and mechanical deformations. When the system is only under vibration, at a fixed amplitude and frequency, a transition from a disordered particle configuration to a more ordered one with square clusters aligned with the walls of the container is observed; however, the formation of some grains differently oriented prevents a complete system ordering. This configuration is very stable and no further increase of order occurs. When the system is submitted additionally to cyclic shearing by deforming the boundaries (a rhomboidal frame), a transition towards a complete square crystal configuration rapidly occurs. The larger the strain, the shorter the annealing time, although with lower stability. We characterize the structural features of the system through the radial distribution function and fourth and sixth-bond-orientational order parameters. Our results reveal an efficient and simple mechanism to optimize the packing of particles of cubic geometry, with potential applications in material storage, transport, and in industrial processes. • Cubes ordering is achieved faster using mechanical deformations than only vibration. • The larger the strain, the shorter the annealing time. • The fourth-bond-orientational order parameter captures well the ordering changes. • The formation of grains differently oriented prevents a complete system ordering. • Mechanical deformations destroy grains differently oriented. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanoengineered synthetic Anti-EGFR nanobody for EGFR detection. • On-demand engineered Nb with different tags for its oriented functionalization. • Specific detection by EIS at disposable screen-printed carbon electrodes. • Characterization by XPS confirms nanobiosensor assembly and correlates with EIS. • Discrimination of EGFR levels in different cell lines. Two engineered synthetic nanobody-based nanobiocomposite platforms were developed for label-free electrochemical detection of the epithelial growth factor receptor (EGFR) biomarker. Screen-printed carbon electrodes (SPCE) were decorated either with NiO nanoparticles (NPs) or poly(thiophene acetic acid) (PTAA) to link the anti-EGFR nanobody (Nb) and form nanobiocomposites for detecting the EGFR biomarker by electrochemical impedance spectroscopy (EIS). The nanoarchitectures were prepared by in situ electrosynthesis of NiO NPs or PTAA layers at SPCEs. A modified version of the 9G8 Nb (Nb9G8m), specific for the EGFR (anti-EGFR), was designed and produced as the nanobiosensor bioreceptor. This Nb was engineered to provide a hexahistidine tag (6xHis-tag) and a lysine (Lys) dual functionality to form a (6xHis-tag)/Ni2+ or Lys/PTAA interface. The biosensing interfaces were characterized by field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, cyclic voltammetry, and EIS. The nanobody/nanobiocomposite-based biosensors detected EGFR proteins in a linear range from 0.25 to 50 μg mL−1 and 0.5 to 50 μg mL−1, with limits of detection of 0.46 μg mL−1 and 1.14 μg mL−1, for NiO- and PTAA-based platforms, respectively. The biosensing platforms offer high simplicity, specificity, and selectivity to detect EGFR, but Nbs can be readily engineered to detect other (glycol)proteins. Finally, as a proof of concept, the EGFR was detected in several tumor cell lines, differentiating biomarker expression among them. [ABSTRACT FROM AUTHOR]

Context. We have studied clusters of self-gravitating collisionless Newtonian bosons in their ground state and in the presence of the cosmological constant to model dark haloes of dwarf spheroidal (dSph) galaxies. Aim. We aim to analyse the influence of the cosmological constant on the structure of these systems. Observational data of Milky Way dSph galaxies allow us to estimate the boson mass. Methods. We obtained the energy of the ground state of the cluster in the Hartree approximation by solving a variational problem in the particle density. We have also developed and applied the virial theorem. Dark halo models were tested in a sample of 19 galaxies. Galaxy radii, 3D deprojected half-light radii, mass enclosed within them, and luminosity-weighted averages of the square of line-of-sight velocity dispersions are used to estimate the particle mass. Results. Cosmological constant repulsive effects are embedded in one parameter ξ. They are appreciable for ξ > 10−5. Bound structures appear for ξ ≤ ξc = 1.65 × 10−4, what imposes a lower bound for cluster masses as a function of the particle mass. In principle, these systems present tunnelling through a potential barrier; however, after estimating their mean lifes, we realize that their existence is not affected by the age of the Universe. When Milky Way dSph galaxies are used to test the model, we obtain 3.5-1.0+1.3 × 10-22 $3.5_{-1.0}^{+1.3}\times 10^{-22}$ 3.5 − 1.0 + 1.3 × 10 − 22 eV for the particle mass and a lower limit of 5.1-2.8+2.2 × 106M⊙ $5.1^{+2.2}_{-2.8}\times 10^6\,{M_{\odot}}$ 3.5 − 1.0 + 1.3 × 10 − 22 for bound haloes. Conclusions. Our estimation for the boson mass is in agreement with other recent results which use different methods. From our particle mass estimation, the treated dSph galaxies would present dark halo masses ~5–11 ×107M⊙. With these values, they would not be affected by the cosmological constant (ξ < 10−8). However, dark halo masses smaller than 107M⊙ (ξ > 10−5) would already feel their effects. Our model that includes dark energy allows us to deal with these dark haloes. Assuming quantities averaged in the sample of galaxies, 10−5 < ξ ≤ ξc dark haloes would contain stars up to ~8–15 kpc with luminosities ~9–4 ×103L⊙. Then, their observation would be complicated. The comparison of our lower bound for dark halo masses with other bounds based on different arguments, leads us to think that the cosmological constant is actually the responsible of limiting the halo mass. [ABSTRACT FROM AUTHOR]

The civil engineering area has long been known for not being associated with high tech startup creation. This is a sign of the low innovation which is confirmed by its low patenting level thus contributing to undermine the prestige of this area. Still this area has an important role to play given the environmental impacts of the construction industry that will be exacerbated in the next decades due to the growth in world population, each day there are about 220,000 new inhabitants which means more than 9,7 billion people by 2050 and 11,2 billion by 2100. A direct consequence of such growth relates to a steady increase of energy consumption which is the source of two-thirds of global greenhouse-gas emissions. The building sector is responsible for high energy consumption and its global demand is expected to grow in the next decades. Between 2010 and 2050 the global heating and cooling needs are expected to increase 70% in residential buildings and 90% in commercial buildings. Major energy efficiency measures are therefore crucial to reduce energy consumption and greenhouse-gas emissions of the building sector. This includes development of new technologies and materials to improve greatly energy efficiency. Since information derived from knowledge is critical for individuals to transform innovative ideas into commercial products and services, this paper reviews recent developments on nano and bio based innovations important for an energy efficient built environment. This review may contribute to enhance the innovation and patenting activity in civil engineering. This may help to foster the creation of high tech startups for an energy efficient built environment. [ABSTRACT FROM AUTHOR]

β-1,4-GalT-V is an enzyme with glycosyltransferase activity that glycosylates proteins and synthesizes the lactosylceramide sphingolipid in the Golgi apparatus. Colorectal cancer (CRC) tumor cells produce these biomolecules in high concentrations concerning normal cells, releasing them into the blood serum. Hence, β-1,4-GalT-V glycoprotein has emerged as a promising CRC biomarker, and its detection opens opportunities for the diagnosis/prognosis of CRC. We report the first capacitive nanobiosensor for the detection of β-1,4-GalT-V based on disposable screen-printed carbon electrodes (SPCEs) nanostructured with gold nanorods (AuNRs) and the Prussian blue (PrB) redox-active compound. AuNRs increased the SPCE surface area for antibody immobilization by physical adsorption and promoted the deposition of PrB onto the SPCE surface. Antibody-glycoprotein molecular biorecognition event onto the SPCE/AuNRs/PrB surface perturbed the PrB redox density-of-states and hence redox capacitance (C μ ̅ ). We found that changes in the inverse of C μ ̅ correlated well with the increasing concentrations of β-1,4-GalT-V in the linear range from 50 to 400 fM with a sensitivity of 1.5 µF fM-1 cm-2 and a limit of detection of 20 fM. The nanobiosensor detected the β-1,4-GalT-V glycoprotein from raw human serum samples with high specificity, ultrasensitivity, and reagentless label-free electrochemical transduction. The nanobiosensor could be applied as a CRC diagnosis/prognosis tool in a decentralized setting, with minimal patient sample manipulation and rapid response. [Display omitted] • First capacitive nanobiosensor for determining β-1,4-GalT-V CRC biomarker. • Ultrasensitive detection by ECS using disposable screen-printed carbon electrodes. • Characterization by XPS confirms nanobiosensor assembly and correlates with ECS. • Detection in undiluted serum at femtomolar levels, with high specificity. • LOD 350-fold lower concerning the only biosensor reported for β-1,4-GalT-V. [ABSTRACT FROM AUTHOR]

Studies of the development of anti-social behavior from adolescence through adulthood have suggested that early onset of offending tends to be associated with a lengthier criminal career. Recently, Bacon and colleagues uncovered a somewhat divergent finding in that late onset of delinquency was associated with subsequent offending among members of the 1958 Philadelphia Birth Cohort. This paper furthers this line of research by adopting a different methodological orientation, a finite mixture-modeling framework, to the 1958 Cohort data. Findings suggest that late adolescence onset of delinquency is associated with more offending in adulthood. Direction for future research is discussed. [ABSTRACT FROM PUBLISHER]

The simulation of complex reactive flows in combustion applications generally requires a large amount of computational power, and the reactive part of the solution is usually the most time consuming. Detailed chemical kinetics mechanisms can reach up to tens of thousands species, while numerical simulations of complex reactive flows can handle mechanisms, at most, with a few hundred species. Virtual kinetic mechanisms are a very effective strategy to drastically reduce the computational time spent in the reactive part of numerical simulations. They are formed by artificial species and reaction paths, that are optimized to reproduce the important characteristics of a canonical problem of interest. This work presents the development of a virtual mechanism able to reproduce the temperature evolution and ignition delay times of the thermal ignition of a homogeneous, constant mass, constant pressure, adiabatic, fuel-air mixture. Three different reaction structures are built for a methane-air mixture and their predictions are tested over a range of temperatures from 1000 K to 1500 K and pressures from 1 atm to 3 atm. The limitations observed are due to the small number of reactions and parameters of the kinetic model. However, mechanism reduction methodologies, such as DRG, may present much larger errors if used to achieve the same mechanism size of the virtual mechanisms presented in the current study. [ABSTRACT FROM AUTHOR]

Background and Purpose: The synthetic peptide PnPP-19 has been studied as a new drug candidate to treat erectile dysfunction. However, PnTx2-6, the spider toxin from which the peptide was designed, induces hyperalgesia. Therefore, we intended to investigate the role of PnPP-19 in the nociceptive pathway.Experimental Approach: Nociceptive thresholds were measured by paw pressure test. PnPP-19 was administered intraplantarly alone or with selective cannabinoid or opioid receptor antagonists. The hydrolysis of PnPP-19 by neutral endopeptidase (NEP) (EC 3.4.24.11), an enzyme that cleaves enkephalin, was monitored by HPLC and the cleavage sites were deduced by LC-MS. Inhibition by PnPP-19 and Leu-enkephalin of NEP enzyme activity was determined spectrofluorimetrically.Key Results: PnPP-19 (5, 10 and 20 μg per paw) induced peripheral antinociception in rats. Specific antagonists of μ opioid receptors (clocinnamox), δ opioid receptors (naltrindole) and CB1 receptors (AM251) partly inhibited the antinociceptive effect of PnPP-19. Inhibition of fatty acid amide hydrolase by MAFP or of anandamide uptake by VDM11 enhanced PnPP-19-induced antinociception. NEP cleaved PnPP-19 only after a long incubation, and Ki values of 35.6 ± 1.4 and 14.6 ± 0.44 μmol·L(-1) were determined for PnPP-19 and Leu-enkephalin respectively as inhibitors of NEP activity.Conclusions and Implications: Antinociception induced by PnPP-19 appears to involve the inhibition of NEP and activation of CB1, μ and δ opioid receptors. Our data provide a greater understanding of the antinociceptive effects of PnPP-19. This peptide could be useful as a new antinociceptive drug candidate. [ABSTRACT FROM AUTHOR]

The taruka is a charismatic species, and we therefore intend to approach La Paz city authorities to secure their support in using the taruka as a flagship species for local biodiversity conservation and education programmes. The species was believed to have gone extinct in La Paz valley by the end of 1980s, but was resighted as close as 8.5 km from the southern border of La Paz city c. 15 years ago (Rechberger et al., 2014, I Oryx i , 48, 445-450). Although we have not rigorously monitored the advance of this population, the fact that a species formerly believed extinct within La Paz valley has been sighted so close to the city suggests that the species is recovering locally. [Extracted from the article]

This paper reports the synthesis and characterization of an oxide type La0.8Sr0.2MnO3, using a wet chemistry route, which allows to obtain a ceramic material with physicochemical properties and structural characteristics of relevant importance for application as an electrode component for use in solid oxide fuel cells devices (SOFC). The synthesized material was characterized by X-ray diffraction (XRD), obtaining a material with perovskite structure. Results from High-resolution transmission electron microscopy (HRTEM), confirm the synthesis of a solid with regular morphology preferentially oriented in the (1 1 2) plane, with d spacing calculated of about 0.25 nm based on the results of HRTEM and XRD. The La0.8Sr0.2MnO3 composition was determined by X-ray microanalysis by energy dispersive (EDX), indicating a good agreement between the proposed and obtained composition. Surface area and pore volume measured by BET method would suggest that the material maintain their textural and surface characteristics depending on the synthesis method used. [ABSTRACT FROM AUTHOR]

This study has investigated the joint effect of several mix parameters on the properties of foam geopolymers. The mix parameters analysed through a laboratory experiment of 54 different mortar mixes were, sodium silicate/sodium hydroxide mass ratio (2.5, 3.5, 4.5), activator/binder mass ratio (0.6, 0.8, 1.0), chemical foaming agent type (hydrogen peroxide (H 2 O 2 ) and sodium perborate (NaBO 3 )) and foaming agent mass ratio content (1%, 2%, 3%). Properties, SEM and FTIR analysis and cost analysis are included. The results show that the sodium perborate over performs hydrogen peroxide leading to a lower overall thermal conductibility of foam geopolymers. Mixtures with a low thermal conductivity of around 0.1 W/(m·K) and a compressive strength of around 6 MPa were achieved. The cost analysis show that the foaming agents are responsible for a small percentage of foam geopolymers total cost being that the alkaline activators are responsible for more than 80%. [ABSTRACT FROM AUTHOR]

Ethanol production using self-flocculating yeast in a batch tower upflow reactor system operating with a recirculation loop was examined. Ethanol productivity, yield, and residual sucrose concentration were evaluated experimentally according to a central composite design with initial cell and sucrose concentrations and recirculation flow rate as independent variables. Yeast cell concentration strongly influenced the reactor performance. Alcoholic fermentation was conducted using this strain and reactor configuration which allowed for high productivity and high sucrose conversion. The ethanol yield was comparable with industrial yields. A kinetic study of the fermentation process under optimized conditions was performed using the experimental data and considering inhibition by sucrose and ethanol. [ABSTRACT FROM AUTHOR]

The conflict between human activities and vampire bats (Desmodus rotundus) has been evident in the Bolivian Prepuna for decades. Vampire attacks on domestic goats have been frequently reported, and led to the application of inadequate control strategies of vampire populations. In order to contribute to the management and mitigation of this conflict, we assessed whether the incidence of attacks is associated with factors like the distribution and abundance of livestock, the distance from the stockyards to vampire roosts, the habitat type, and the relative abundance of the vampire. The results suggest that the incidence of attacks decreases with the density of goats and the distance from stockyards to vampire roosts, while it increases with the relative abundance of vampires in the area. Besides, the abundance of vampires is positively correlated to the availability of roosts near their foraging areas and is not correlated to livestock abundance. We propose that the main factor limiting the abundance of vampires, and indirectly determining the incidence of attacks, is the availability of roosts near foraging areas. Coincidently, the localities situated near roosts presented higher abundance of vampires and recorded the highest incidence of attacks on livestock. Based on our results, we propose the regulation of mining operations involving potential vampire refuges. We also suggest the implementation of monitoring programs of the incidence of attacks as an indicator of the vampire abundance. [ABSTRACT FROM AUTHOR]

A rigorous dimensionless analysis of simultaneous heat and mass transfer equations for food drying was developed and simplified for constant properties. From the simplified result, an analytical solution in 1D rectangular coordinate system was obtained. As opposed to Luikov's Equations (LE), the reported solution considers the effect of temperature on interface moisture content. The analytical solution was obtained by Laplace transform and complex inversion integral with space dependent function as initial conditions. The solution behavior compared with some experimental data was detailed, and the potential of the reported solution for the study of interface phenomena and variable mass transfer properties was discussed. [ABSTRACT FROM AUTHOR]

Wildlife is often blamed for causing damage to human activities, including agricultural practices and the result may be a conflict between human interests and species conservation. A formal assessment of the magnitude of damage is necessary to adequately conduct management practices and an assessment of the efficiency of different management practices is necessary to enable managers to mitigate the conflict with rural people. This study was carried out to evaluate the effectiveness of agricultural management practices and controlled hunting in reducing damage to subsistence annual crops at the Cotapata National Park and Natural Area of Integrated Management. The design included seven fields with modified agricultural practices, four fields subjected to control hunting, and five fields held as controls. We registered cultivar type, density, frequency of visiting species to the field, crops lost to wildlife, species responsible for damage, and crop biomass. Most frequent species in the fields were Dasyprocta punctata and Dasypus novemcinctus. Hunted plots were visited 1.6 times more frequently than agriculturally managed plots. Crop lost to wildlife averaged 7.28% at agriculturally managed plots, 4.59% in plots subjected to hunting, and 27.61% in control plots. Species mainly responsible for damage were Pecari tajacu, D. punctata, and Sapajus apella. We concluded that both management strategies were effective to reduce damage by >50% as compared to unmanaged crop plots. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to evaluate the effect of full-fat rice bran (FFRB) inclusion in dry diets with and without enzyme blend (EB) supplementation for adult dogs. The diets contained 0, 20, or 40% of FFRB, replacing the equivalent amount of wheat flour (WF). Experiment 1 evaluated the consumption and preference of diets using a simple choice method with 3 comparisons (0 vs. 20, 0 vs. 40, and 20 vs. 40% FFRB). Experiment 2 investigated the effect of EB supplementation on the apparent digestibility coefficients (ADC) of nutrients and GE, fecal characteristics, urinary pH, Ca and P balance, and ME of the diets. In Exp. 1, the results indicated that FFRB included in diets up to 40% did not affect the preference or consumption of food by dogs (P < 0.05). In Exp. 2, increasing levels of FFRB in the diet linearly reduced the ADC of nutrients, GE, and ME (P < 0.05). The addition of EB had no effect on any of the variables examined. Regression analysis enabled estimation of the ADC in FFRB; and ADC of DM, CP, ether extract, GE; and the apparent coefficient of ME were 60.5, 74.8, 88.4, 70.8, and 66.4%, respectively. The inclusion of 20 or 40% FFRB in the diets did not affect urinary pH but caused an imbalance in the Ca and P metabolism when included at 40% (P < 0.05), which could be one of the limitations for greater inclusion of FFRB. The ME of FFRB was estimated to be 3,443 kcal/kg DM. The FFRB appears to be palatable for adult dogs, and although ADC was reduced by 40% FFRB in the diet, this ingredient has the potential for inclusion at 20% of diets for dogs, depending on the other ingredients used to achieve adequate Ca and P balance. The inclusion greater than 20% tends to increase P in the diet and reverse the relationship between Ca and P. [ABSTRACT FROM AUTHOR]

We study experimentally how the bouncing dynamics of a hollow ball on a vibrating plate is modified when it is partially filled with liquid or grains. Whereas empty and liquid-filled balls display a dominant chaotic dynamics, a ball with grains exhibits a rich variety of stationary states, determined by the grain size and filling volume. In the collisional regime, i.e., when the energy injected to the system is mainly dissipated by interparticle collisions, an unexpected period-1 orbit appears independently of the vibration conditions, over a wide range. This is a self-regulated state driven by the formation and collapse of a granular gas within the ball during one cycle. In the frictional regime (dissipation dominated by friction), the grains move collectively and generate different patterns and steady modes: oscillons, waves, period doubling, etc. From a phase diagram and a geometrical analysis, we deduce that these modes are the result of a coupling (synchronization) between the vibrating plate frequency and the trajectory followed by the particles inside the cavity. [ABSTRACT FROM AUTHOR]

The taruka Hippocamelus antisensis, a species of deer categorized as Vulnerable on the IUCN Red List, was thought to be locally extinct in the environs of La Paz, Bolivia. However, local people from Mecapaca municipality reported seeing tarukas at their former community establishment, which had been abandoned several years previously. After confirming the presence of taruka we conducted intensive surveys from which we estimated minimum abundance, and then calibrated relative abundance indices (faecal and track counts) to the abundance estimate. Using these calibrated indices we carried out a preliminary estimate of the total abundance of the species in the municipality of Mecapaca. We also carried out conservation education activities with teachers and students at local schools, which we discuss here in terms of the long-term conservation of this threatened species. [ABSTRACT FROM AUTHOR]

Context. Cold dark matter inhomogeneities are considered in a homogeneous background of matter, radiation, and the cosmological constant in a flat universe. Aims. We investigate the influence of the cosmological constant on the non-linear collapse of cold dark matter clusters. Methods. For simplicity, a spherical infall model has been used to describe the collapse of non-relativistic mass shells; besides, an average distribution of density around a cluster of galaxies has been taken. Boundary conditions are imposed by the solution of the linearized equation for the growth of matter perturbations and by the cold dark matter power spectrum. Results. For an average cluster, the radii of shells and masses enclosed by them have been obtained at their zero proper acceleration (ZA) redshifts, at their turn-around (TA) redshifts and at their virialization (VIR) redshifts. According to our results at present, the shell that reaches its turn-around point shows [rTA]0 = 6.85 Mpc and [MTA]0 = 6.76 × 1014 M⊙. The virializing shell fulfills [rTA]0 = 4.57 [rVIR]0 and [MVIR]0 = 1.95 [MVIR]0. These results differ appreciably from those derived from a model with cosmological constant equal to zero in a flat universe: [rTA(Λ = 0)]0 = 6.62 [rVIR(Λ = 0)]0 and [MTA(Λ = 0)]0 = 5.26 [MVIR(Λ = 0)]0; this discrepancy could be considered as a new independent proof of the existence of dark energy. The shell with zero proper acceleration presents [rZA]0 = 1.59 [rTA]0 and [MZA0 = 1.63 [MTA]0. We have found that there is a limit to the mass of the average cluster, which is able to virialize; its value is {MVIR}MAX = 8.1 × 1014 M⊙. As expected, we found that shells present null proper acceleration at redshift values that are smaller than 0.755. Conclusions. We have noticed that the cosmological constant imposes an upper limit for the mass enclosed by shells, which are able to reach zero proper velocity. Hence, this mass is the maximum mass of the virialized core, {MVIR}MAX. For the average cluster addressed in this work, the value is 2.34 times the mass of the virialized core at present. Shells enclosing masses M ⪢ {MVIR}MAX achieve zero proper acceleration and speed up, moving away from the virialized core, and never reach a turn-around point. Shells with M » {MVIR}MAX show zero proper aceleration at redshifts close to that at which the universe background acceleration is null. Finally, we have found that the relation between shell proper velocities and their radii can be adjusted by a straight line at z = 0 and from approximately 20 up to 40 Mpc; however, this line does not intercept the origin as velocities due to the Hubble flux do. [ABSTRACT FROM AUTHOR]

The effect of frequency of supply of forage (V) and concentrate (C) on the performance of cows and heifers in feedlot was studied. The treatments were the following frequencies in the supply: 2 V/C= V and C twice daily; 1 V/C= V and C once daily; 1 V/2C= once V and C twice daily, 1 V/3C= once V and C three times a day, for the cows or heifers. The experimental design was completely randomized in factorial arrangement 4 x 2, with four replications. There was no significant interaction between frequency of supplying and category animal. The dry matter intake (DMI) was superior for the animals fed 1 V/2C or 1 V/3C a day in relation with the supply of 2 V/C and 1 V/C, presenting values of 11.7; 11.4; 10.6 and 10.7 kg, respectively. The average daily gain (ADG) was not influenced by the frequency of supplying. The DMI was higher in cows (12.6 kg) than heifers (9.57 kg), having no difference in the weight gain. Increasing frequency of feeding the concentrate to two or three times a day, provided greater consumption, not influencing the weight gain of cows and heifers confined. [ABSTRACT FROM AUTHOR]

Highlights: [•] Horizon 2020 constitutes the most important instrument for research and innovation in the world. [•] Horizon 2020 sustainability focus will have a strong impact on the European construction industry. [•] Development of eco-efficient building materials fits well on the Horizon 2020 targets. [•] Nanotech energy efficiency building materials can constitute a crucial Key Enabling Technology-KET. [Copyright &y& Elsevier]

Abstract: Analysis of teleseismic records obtained in two broadband seismic stations of three components located on the Andean region of Colombia is presented in this work. The two stations are located at the Western Cordillera (WC), station BOL, and at the Central Cordillera (CC), station PBLA. The analysis of seismograms was performed by inversion of the receiver functions (RF) in order to obtain the crustal velocity structure beneath the receivers. The receiver function is a spectral ratio obtained from teleseismic earthquakes recorded by broadband seismic stations, which allows the calculation of the velocity structure beneath the receiver by removing source effects in the horizontal components of the seismic traces. Data stacking was performed in order to improve signal to noise ratio and then the data was inverted by using two optimization algorithms: a genetic algorithm (GA), and a simulated annealing algorithm (SA). The present work calculates the receiver functions using teleseismic earthquakes at epicentral distances (Δ) ranging between 30° and 90° and recorded at the two stations within the years 2007 and 2009. Delay times between P and PS waves converted at the Moho boundary were used to constrain the velocity structure. The receiver functions at the stations were generated from seismic events within a broad range of back azimuth. Data from gravity and magnetism were also used during the geophysical survey. The depth of the Moho boundary was found to be at 40 km in the WC beneath station BOL and at 43 km in the CC beneath station PBLA. The upper crust, with a thickness of 5 km, is characterized by a shear wave velocity of about 3.0 km s−1; the shallower layers, at approximately 1.0 km, have shear wave velocities between 2.2 and 2.6 km s−1, which corresponds to sediments overlying the upper crust. These observations support the hypothesis of a thickness of the crust at the root of the mountain range to be between 32 and 50 km. The calculated receiver functions were compared with artificial ones generated from the inversion of 48000 models of horizontal layers for each station using a GA and an SA that allowed a satisfactory coverage of all the sample space in order to avoid non-unique solutions. Beneath station BOL a moderate low-velocity zone (LVZ) was found, which was caused by accretionary processes of the ophiolite complex in the WC. [Copyright &y& Elsevier]

Highlights: [•] Production of geopolymers from several aluminosilicate sources. [•] Prediction mechanical properties by gene expression programming. [•] The best performance network was obtained by utilizing 6 Sub-ETs. [ABSTRACT FROM AUTHOR]

Highlights: [•] NOx emissions are more than 53% reduced. [•] NO x emissions were 37.3mg/km: potential for achieving EURO 6 and future emission legislation. [•] HC emissions 5% higher with HCCI but still lower than Euro 6 limits. [•] CO emissions more than 30% lower with HCCI operation. [•] Fuel economy is 21% better with HCCI operation. [Copyright &y& Elsevier]

A ball dropped over a solid surface bounces several times before a complete stop. The bouncing can be reduced by introducing a liquid into the ball; however, the first rebound remains largely unaffected by the fluid. Granular materials can also work as dampers. We investigated the rebound of a container partially filled with a given mass of grains mi. During the collision, the kinetic energy of the container is partially transferred to the grains, the rebound is damped, and the fast energy dissipation through inter-particle collisions and friction decreases the bouncing time dramatically. For grain-filled cylinders, a completely inelastic collision (zero rebound) is obtained when mi ⩾ 1.5εorc , where eof and mcg are the coefficient of restitution and mass of the empty container. For grain-filled spheres, the first rebound is almost undamped, but the second collision is completely inelastic if mi⪢ mcg. These findings are potentially useful to design new granular damping systems. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, six different models based on artificial neural networks have been developed to predict the compressive strength of different types of geopolymers. The differences between the models were in the number of neurons in hidden layers and in the method of finalizing the models. Seven independent input parameters that cover the curing time, Ca(OH)2 content, the amount of superplasticizer, NaOH concentration, mold type, geopolymer type and H2O/Na2O molar ratio were considered. For each set of these input variables, the compressive strength of geopolymers was obtained. A total number of 399 input-target pairs were collected from the literature, randomly divided into 279, 60 and 60 data and were trained, validated and tested, respectively. The best performance model was obtained through a network with two hidden layers and absolute fraction of variance of 0.9916, the absolute percentage error of 2.2102 and the root mean square error of 1.4867 in training phase. Additionally, the entire trained, validated and tested network showed a strong potential for predicting the compressive strength of geopolymers with a reasonable performance in the considered range. [Copyright &y& Elsevier]

We calculate the range of possible masses for dark spheres of bound fully degenerate fermions as a function of the fermion mass. The cosmological constant is included in our calculations. We deduce that the minimum fermion mass that is able to give rise to degenerate fermion clusters is ∼0.02 g-1/4 eV, where g is the spin degeneracy parameter. We show that degenerate fermions of mc2 ≈ (15-30) g-1/4 eV can build bound degenerate dark haloes that could reproduce the values of the rotation velocities of galaxies. The masses and radii derived for these degenerate dark haloes of typical galaxies, without considering any cosmological information, agree with the Jeans masses and radii of a cosmological background of ∼(20-30) g-1/4 eV degenerate fermions at redshift z ≈ 50. However, degenerate fermion objects of 1015 M☉ composed of these particles are too small to constitute the dark halo of galaxy clusters. We also derive degeneracy conditions for hot and cold dark matter fermions. [ABSTRACT FROM AUTHOR]

Abstract: The deterioration of reinforced concrete structures is a very common problem due to the fact that this material has a high permeability which allows water and other aggressive media to enter, thus leading to corrosion problems. The use of sealers is a common way of contributing to concrete durability. However, the most common ones are based on organic polymers which have some degree of toxicity. The Regulation (EU) 305/2011 related to the Construction Products Regulation emphasizes the need to reduce hazardous substances. Therefore, new low toxicity forms to increase concrete durability are needed. Recent investigations in the field of biotechnology show the potential of bioinspired materials in the development of low toxic solutions. This paper reviews current knowledge on the use of bacteria for concrete with enhanced durability. It covers the use of bacteria in concrete mix and also biomineralization in concrete surface treatments. Investigation gaps are described. Results from practical applications in which there is exposure to environmental conditions are still needed in order to confirm the importance of this new approach. [Copyright &y& Elsevier]

Abstract: Although the unsustainability of the human civilization has been recognized long ago, little has ever been done to change it. During the last century, materials use increased 8-fold and as a result Humanity currently uses almost 60 billion tons (Gt) of materials per year. The construction industry alone consumes more raw materials than any other economic activity. However, research on construction materials still is excessively focused on their mechanical properties with minor concerns regarding environmental considerations. In September of 2000 189 UN member states signed the Millennium Development Goals (MDGs), in which the seventh goal is related to environmental sustainability. This is a cornerstone event of paramount significance. However, research in the field of the built environment especially on the field of construction materials still seems unable to recognize its importance. This paper provides some insights on future construction materials research priorities in the context of the seventh MDG. It reviews publication patterns on the field of construction materials highlighting investigations gaps and misdirected research lines. It addresses the importance of nano and biotech hot areas and briefly analyzes the gap between research and market use. [Copyright &y& Elsevier]

Abstract: According to the 2011 ERMCO statistics only a mere 11% of the ready-mixed concrete class production relates to the HPC target, furthermore, this percentage remains unchanged at least since the year 2001. This represents a strange option from the construction industry since HPC offers several advantages over normal-strength concrete, namely, high strength and high durability. Therefore, HPC allows for concrete structures with less steel reinforcement and a longer service life, both of which are crucial issues in the eco-efficiency of construction materials. Although nanotechnology is a very hot issue the fact is that investigations on the field of concrete with nanoparticles are rare (100 in 10,000 Scopus concrete related articles published in the last decade). Actually, it remains to be seen how this research area will contribute to concrete eco-efficiency. This paper summarizes current knowledge on the field of concrete containing nanoparticles. It includes the influence of nanoparticles on the mechanical properties of concrete and on its durability. It also includes calcium leaching control. Moreover, the problem of efficient dispersion of nanoparticles is analyzed. [Copyright &y& Elsevier]

We study the spontaneous formation of granular towers produced when dry sand is poured on a wet sand bed. When the liquid content of the bed exceeds a threshold value W", the impacting grains have a nonzero probability to stick on the wet grains due to instantaneous liquid bridges created during the impact. The trapped grains become wet by the capillary ascension of water and the process continues, giving rise to stable narrow towers. The growth velocity is determined by the surface liquid content which decreases exponentially as the tower height augments. This self-assembly mechanism (only observed in the funicular and capillary regimes) could theoretically last while the capillary rise of water is possible; however, the structure collapses before reaching this limit. The collapse occurs when the weight of the tower surpasses the cohesive stress at its base. The cohesive stress increases as the liquid content of the bed is reduced. Consequently, the highest towers are found just above W". [ABSTRACT FROM AUTHOR]

Abstract: Infrastructure rehabilitation represents a multitrillion dollar opportunity for the construction industry. In USA alone the rehabilitation needs are estimated to exceed 1.6 trillion dollars over the next 5years. Since the majority of the existent infrastructures are concrete based this means that concrete infrastructure rehabilitation is a hot issue to be dealt with. Besides the sooner concrete deterioration is tackled the lower are the rehabilitation costs. This paper provides a literature review on concrete repair materials, highlighting the current problems face by them. It covers concrete surface treatments, patch repair and FRP strengthening. The case of trenchless rehabilitation of concrete sewage pipelines is also discussed. The potential of geopolymers to overcome those limitations is analyzed. [Copyright &y& Elsevier]

Abstract: The 70% minimum construction and demolition wastes-C&DW recycling rate set by the Revised Waste framework Directive No. 2008/98/EC to be enforced beyond 2020, will increase the need of effective recycling methods in a dramatic manner. So far, recycled aggregates (which constitute the majority of C&DW) are reused in low volume percentages for average compressive strength concretes and mostly as road sub-base and back-fill material which, in turn, constitutes a down-cycling option. Most investigations related to concrete made with recycled aggregates use aggregates produced in laboratory context which are not contaminated at all. It is then no surprise to find out that some investigations shows the potential to reuse as much as 100%, however, industrially produced recycled aggregates contain a certain level of impurities that can be deleterious for Portland cement concrete, thus making very difficult for the concrete industry to use such investigations unless uncontaminated recycled aggregates are used. This paper reviews current knowledge on concrete made with recycled aggregates, with a special focus on the crucial importance of impurities presence and how those aggregates are not suitable for the production of HPC. Also, the potential of geopolymers to produce HPC based on high volume recycled aggregates is discussed. [Copyright &y& Elsevier]

Abstract: Carbonation is a major cause of concrete structures deterioration leading to expensive maintenance and conservation operations. The eco-efficient construction agenda favours the increase of the use of supplementary cementing materials (SCMs) to reduce Portland cement’s consumption and also the use of recycled aggregates concrete (RAC) in order to reduce the consumption of primary aggregates and to avoid landfill disposal of concrete waste. There is a wide range of literature published on the field of concrete carbonation related to the use of SCMs and/or RCA. However, the different conditions used by different authors limit comparison and in some cases contradictory findings are noticed. Besides, since most investigations are based on the use of the phenolphthalein indicator, which provides a poor estimate of the real concrete carbonation depth, there is a high probability that past researches could have underestimate the corrosion potential associated to concrete carbonation. This paper reviews current knowledge on concrete carbonation addressing carbonation depth’s measurement, the use of SCMs and or RAC. [Copyright &y& Elsevier]