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Abstract: Chronically epileptic male adult rats in the pilocarpine model of temporal lobe epilepsy (TLE), exhibited gross expansion of abdominal fat mass and significant weight gain several months after induction of status epilepticus (SE) when compared to control rats. We hypothesized that epileptogenesis can induce molecular changes in the hippocampus that may be associated with metabolism. We determined the expression levels of genes Hsd11b1, Nr3c1, Abcc8, Kcnj11, Mc4r, Npy, Lepr, Bdnf, and Drd2 that are involved in regulation of energy metabolism, in the hippocampus of age-matched control and chronic epileptic animals. Taqman-based quantitative real time polymerase chain reaction (qPCR) and the delta–delta cycle threshold (CT) methods were used for the gene expression assays. Gene expression of Hsd11b1 (cortisol generating enzyme) was significantly higher in epileptic versus control rats at 24h and 2months, after induction of SE. Nr3c1 (glucocorticoid receptor) mRNA levels on the other hand were down-regulated at 24h, 10days and 2months, post SE. Abcc8 (Sur1; subunit of ATP-sensitive potassium (KATP) channel) was significantly down-regulated at 10days post SE. Kcnj11 (Kir6.2; subunit of ATP-sensitive potassium (KATP) channel) was significantly up-regulated at 24h, 1month and 2months post SE. Thus, we demonstrated development of obesity and changes in the expression of metabolic genes in the hippocampus during epileptogenesis in male rats in the pilocarpine model of TLE. [Copyright &y& Elsevier]

Impact experiments in granular media are usually performed with solid projectiles that do not fragment at all. Contrastingly, we study here the morphology produced by the impact of spherical granular projectiles whose structure is utterly lost after collision. Simple and complex craters are observed, depending on the packing fraction of the balls. Their diameters D and depths z are analyzed as a function of the drop height h. We find the same power law D ∝ h1/4 obtained with solid spheres, but a discontinuity at a certain threshold height, related to the cohesive energy of the projectiles, shows up. Counterintuitively, instead of a monotonic increase with the collisional energy, z becomes constant above this threshold. [ABSTRACT FROM AUTHOR]

Abstract: This study has investigated the joint effect of several factors on the workability and mechanical strength of alkali-activated metakaolin based mortars. The factors analysed through a laboratory experiment of 432 specimens, pertaining to 48 different mortar mixes were, sodium hydroxide concentration (10M, 12M, 14M, 16M), the superplasticizer content (1%, 2%, 3%) and the percentage substitution of metakaolin by calcium hydroxide in the mixture (5%, 10%). The results show that the workability decreases with the concentration of sodium hydroxide and increases with the amount of calcium hydroxide and superplasticizer. The results also show that the use of 3% of superplasticizer, combined with a calcium hydroxide content of 10%, allows improving the mortar flow from less than 50% to over 90%, while maintaining a high compressive and flexural strength. [Copyright &y& Elsevier]

Abstract: Nanotechnology seems to hold the key that allows construction and building materials to replicate the features of natural systems improved until perfection during millions of years. This paper reviews current knowledge about nanotechnology and nanomaterials used by the construction industry. It covers the nanoscale analysis of Portland cement hydration products, the use of nanoparticles to increase the strength and durability of cimentitious composites, the photocatalytic capacity of nanomaterials and also nanotoxicity risks. [ABSTRACT FROM AUTHOR]

Abstract: The ceramic industry is known to generate large amounts of calcined-clay wastes each year. So far a huge part is used in landfills. Reusing these wastes in concrete could be a win–win situation. For one hand by solving the ceramic industry waste problem and at the same time leading to a more sustainable concrete industry by reducing the use of non renewable resources like cement and aggregates and avoiding environmental problems related to land filled wastes. This paper examines the feasibility of using ceramic wastes in concrete. Results show that concrete with 20% cement replacement although it has a minor strength loss possess increase durability performance. Results also show that concrete mixtures with ceramic aggregates perform better than the control concrete mixtures concerning compressive strength, capillary water absorption, oxygen permeability and chloride diffusion thus leading to more durable concrete structures. [Copyright &y& Elsevier]

Abstract: This paper report results of a research project related to the development of an alkali-activated based binder using mineral waste mud from a tungsten mine. Some aspects related to the influence of time and temperature calcination of mine waste mud mixed with sodium carbonate on the compressive strength performance of alkali-activated mortars are reported. Results show that calcination of mine waste mud mixed with sodium carbonate does not lead to the dehydroxylation state. Although they possess early high strength, alkali-activated mortars based on mine waste mud calcined with sodium carbonate present a high amount of sodium efflorescences after water immersion that maybe due to an ineffective chemical combination. [Copyright &y& Elsevier]

Abstract: Classic approaches to polymer-modificated Portland cement based materials usually forget the specific nature of the precast concrete industry and also the economic impacts of each technical option. This manuscript report results of a wider investigation which aims to understand what is the best option for the concrete pipe industry as far as sulphuric acid resistant is concerned, polymer addition or polymer impregnation. Results show that the use of polymer addition it is not economically attractive when compared to polymer impregnation. The increase of costs per meter of pipe is too high. The use of polymer impregnation enhances the chemical resistance of concrete considerably. Furthermore, it is economically viable, especially for smaller diameters. Results also show that using sulphate resistant cements improve the chemical resistance without cost increase. [Copyright &y& Elsevier]

In this study, three different microcellular polyurethane elastomers (MPUE) based on 4,4′-diphenylmethane diisocyanate with different rigid segment contents are prepared (Formulations 1, 2, and 3 with 32, 35, and 42% of rigid segment content, respectively). The MPUE are obtained through a two-step method using a prepolymer system. The samples are analyzed to determine their thermal, morphological, and chemical properties. The thermogravimetric analysis indicates the presence of two degradation stages, referring to the rigid and flexible phases, respectively. The differential scanning calorimetry tests indicate that for the MPUE there was an increase in the glass transition temperature of the flexible phase with an increase in the percent of the rigid phase. An increase in the quantity of the rigid phase present in the MPUE results in greater values for the crosslink density, which in turn results in an increase in the rigidity of the material. The scanning electron microscopy micrographs indicated a large number of closed cells and that a higher rigid segment content give a better cell homogeneity of the samples. [ABSTRACT FROM AUTHOR]

The article discusses the idea of population density and habitat use of Cebus libidinosus in the montane forest of Bolivia. It highlights the estimate of density and habitat use of a population in the montane forest at the outskirts of the Estación Biológica de Tunquini (EBT). It states that the Brown Capuchin Monkey is recognized a plague for citrus and corn cultivars in the Yungas region. Furthermore, it cites that Cebus libidinosus used cultivations more than expected which coincides with the perception of the peasants.

Abstract: In this work, a new approach is presented to allow interference-free determination of Cu (II) by stripping voltammetry using the bismuth-film electrode. The addition of hydrogen peroxide to the electroanalytical cell has promoted complete resolution between re-dissolution peaks of Bi (III) and Cu (II). The absence of interference could be evaluated by the correlation coefficient (r >0.99) between Cu (II) concentration and its shifted current peak (at +212mV) while achieving a slightly fluctuation of the bismuth current peak at −180mV. Studies were performed aiming towards the optimum conditions for trace determination of Cu (II) using hydrogen peroxide. The methodology was applied to a real sample (sugarcane spirits) and the results were compared to those from graphite furnace atomic absorption spectrometry. The analytical parameters of merit and the results of the analysis indicated that the analytical methodology could be readily used for trace determination of Cu (II). [Copyright &y& Elsevier]

The well known and analytically solvable Lipkin–Meshkov–Glick model was devised to test several many-body approximation approaches used in nuclear physics. Here, we use this model to illustrate a method that sets lower bounds for the ground state energy of a quantum Hamiltonian. The idea of the method consists of dividing the Hamiltonian into identical groups of terms that represent subdivisions in the particle population of the system, and then to make an appropriate use of the ground energy of one of these groups. The bounds clearly improve as the size of these groups increases. [ABSTRACT FROM AUTHOR]

It has been suggested that mitochondrial dysfunction and defects in membrane structure could be implied in AD pathogenesis. The aim of the present work was the study of membrane fluidity in submitochondrial platelet particles and erythrocyte membranes from Mexican patients. Blood samples were obtained from 30 patients with Alzheimer disease and 30 aged-matched control subjects. Membrane fluidity determinations were done using a very low concentration of the fluorescent dipyrenylpropane probe incorporated in both types of membranes. This probe is able to give excimer and monomer fluorescence, therefore it can be used to monitor fluidity changes in biological membranes. The data obtained showed that in submitochondrial particles from AD patients, the excimer to monomer fluorescent intensity ratio was lower (0.231 ± 0.008) than aged-matched control subjects (0.363 ± 0.014). Therefore, membrane fluidity was lower in AD samples. On the other hand, we found similar membrane fluidity in erythrocytes from AD patients and aged-matched controls: the fluorescent intensity ratios were 0.312 ± 0.03 and 0.305 ± 0.033, respectively. In addition, lipid peroxidation in submitochondrial particles and erythrocyte membranes was higher in AD samples than in aged-matched controls. These data suggest that submitochondrial platelet particles are more sensitive to oxidative stress than erythrocyte membranes. [ABSTRACT FROM AUTHOR]

Using the Thomas-Fermi method, the density distribution of N electrons confined within a three-dimensional anisotropic parabolic potential is studied. This system simulates the structure of the recently built artificial atoms or quantum dots where a bunch of electrons is trapped in a semiconductor material. In the limit of large N, an analytical solution is obtained. Qualitatively speaking, this solution consists of a constant-density interior and a uniform thin skin that covers it. The asymmetry of the external figure is related to that of the confining potential. The radius, density, eccentricity and skin depth of the system are given as a function of N and of the properties of the confining potential and of the matrix material. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a fluorimetric approach for the determination of cyclofenil, 4-4′-(cyclohexylidenemethylene)bis(phenylacetate), is presented. The method was based on the intense fluorescence (250/410nm) observed after a UV photochemical treatment of cyclofenil. The influence of the pH and solvent system and UV exposure time on the fluorescence magnitude was studied. Optimization of parameters was made using experimental design (factorial design and central composite design). Limit of detection (3S b /m) were estimated to be 1.1×10−8 molL−1 with the linear dynamic range extending up to 8×10−5 molL−1. This analytical approach was tested through the analysis of a commercial pharmaceutical formulation. In this case, tests enabled an average recovery of 98.3±3.9% (for n =9) using the analytical curve. The identification of the fluorescent derivative is proposed based on results achieved from GC-MS. [Copyright &y& Elsevier]

Abstract: This paper presents an experimental study to evaluate the influence of physical and geometrical properties of granite and limestone aggregates on the durability of a C20/25 strength class concrete. Different granite and limestone aggregates were collected from seven quarries. Physical, geometrical and mechanical properties of aggregates as well as the rock weathering state were quantify by several tests such as, abrasion, surface hardness, uniaxial compressive strength, ultrasonic pulse velocity, water absorption by capillarity, vacuum water absorption and oxygen permeability. Using aggregates from each quarry, several C20/25 strength class concrete mixes have been produced, with the same workability and volume proportions. Concrete specimens have been cured under water for 90 days; after that time concrete durability parameters were obtained through tests such as, vacuum water absorption, capillarity water absorption, water permeability and oxygen permeability. Relevant statistical correlations have been obtained between absorption and permeability test of rock material and rock deterioration state (weathering). Valid statistic correlation was also obtained between durability parameters as well as among aggregates geometrical properties and concrete durability parameters. [Copyright &y& Elsevier]

Abstract: We compared species richness and abundance of birds between five patches under selective Alnus exploitation and five patches that have not been harvested for at least 10 years prior to our study, during the early dry season (April–July 2001), in Cotapata National Park. Using “point counts” we recorded birds and their distribution in two (<1.5m and >1.5m) forest layers. Simultaneously we evaluated the floristic structure (size [dbh] distribution, basal area, tree density, tree height, and vegetation cover) and composition (diversity) on three transects placed within each Alnus patch. Both bird diversity and vegetation cover were significantly higher in not presently used patches but only for the higher layer of the forest, whereas plant diversity was higher in presently used patches. Lack of differences between the two types of Alnus patches in any of the vegetation parameters measured in the lower layer was coupled with an indistinct avifauna. Small changes in habitat characteristics following a perturbation like selective logging have the potential to affect richness and abundance of birds, at least within the habitats directly affected by the perturbation. [Copyright &y& Elsevier]

The Thomas-Fermi density distribution of N electrons located inside a box is obtained. This system models some aspects of the structure of the new artificial atoms or quantum dots fabricated using present semiconductor technology. The three-dimensional solutions are obtained by means of a perturbative series, using a convenient dimensionless parameter characteristic of the size of the box and the electron number. The explicit analytic form for the first two terms of the series is derived. PACS No.: 71.10.Ca [ABSTRACT FROM AUTHOR]

Abstract: Our previous work has shown that dioctadecyldimethylammonium bromide (DODAB) bilayer fragments (BF) presented antimicrobial activity, solubilized fungicides, e.g., amphotericin B and miconazole (MCZ), stabilized hydrophobic drug particles and were effective in vivo. Here, the interaction between MCZ and DODAB BF is evaluated from determination of BF loading capacity and effects of drug-to-lipid molar proportion (MP) on particle size, zeta potential and gel-to-liquid-crystalline phase transition . DODAB BF solubilized MCZ over a range of MP. BF loading capacity was 0.5 mM MCZ at 5 mM DODAB. Above this limit, the drug aggregated in the dispersion. At pH 6.3, BF zeta potentials decreased with MP, suggesting insertion of deprotonated drug into the bilayer. MCZ optical spectra in BF were similar to those in best organic solvent, confirming drug solubilization. At MP , BF remained unchanged, suggesting drug capture at BF hydrophobic edges. At MP , decreased, showing MCZ insertion into DODAB bilayer. However, drug was expelled from the bilayer core upon lowering temperature. Minimal fungicidal concentrations against C. albicans were synergically reduced by 10 times for drug/BF. [Copyright &y& Elsevier]

Abstract: In this study, we characterized the role of δ1 and δ2 opioids receptors, as well the involvement of the l-arginine/NO/cGMP pathway in the peripheral antinociception induced by δ-opioid receptor agonist (+)-4-[(αR)-α-((2S,5R)-4-Allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide (SNC80). The paw pressure test was utilized, in which pain sensitivity is increased by intraplantar injection of prostaglandin E2 (2 μg). Administration of SNC80 (20, 40 and 80 μg/paw) decreased the hyperalgesia induced by prostaglandin E2 in a dose-dependent manner. The possibility that the higher dose of SNC80 (80 μg) has a central or systemic effect was excluded, since administration of the drug into the contralateral paw did not elicit antinociception in the right paw. 7-Benzylidenenaltrexone (BNTX), 5, 10 and 20 μg/paw, and 17-(Cyclopropylmethyl)-6,7-didehydro-3,14β-dihydroxy-4,5α-epoxy-6,7-2′,3′-benzo[b]furanomorphinan (naltriben), 2.5, 5 and 10 μg/paw, δ1 and δ2 opioid receptor antagonist respectively, elicited partial antagonism of the peripheral antinociceptive effect of the SNC80 (80 μg). The BNTX (10 μg/paw)–naltriben (5 μg/paw) combination completely antagonized the peripheral antinociception induced by SNC80 (80 μg). Further, blockers of the l-arginine/NO/cGMP pathway, N G-nitro-l-arginine (12, 18 and 24 μg/paw) and methylene blue (125, 250 and 500 μg/paw) were observed reverting the peripheral antinociceptive effect of SNC80. This study provides evidence that the peripheral antinociception induced by SNC80 occurs via δ1 and δ2 receptors and may result from l-arginine/NO/cGMP pathway activation. [Copyright &y& Elsevier]

Abstract: Square-wave adsorptive voltammetry was applied for the determination of cyclofenil at ultra-trace levels. Due to the unstable behavior of cyclofenil, the analyte photochemical derivative was used for quantification. This stable analyte photoderivative was pre-concentrated (30s accumulation time) on the hanging mercury drop electrode (HMDE), using Britton–Robinson buffer (pH 9) as the supporting electrolyte. Under these conditions, the cyclofenil photoderivative presented one reduction peak maximum at −1280mV. Instrumental and experimental parameters were carefully optimised. Limit of detection of 1.5×10−8 moll−1, was achieved with a linear dynamic range from 5×10−8 to 6×10−6 moll−1. This analytical approach was tested through the analysis of one commercial pharmaceutical formulation and analyte spiked urine samples. While no interferences were observed for the analysis of the pharmaceutical tablet, urine samples imposed interferences that were corrected by using the analyte addition technique. Recovery tests enabled results from 93.6 to 106.5%. Repeatability of the measurements was below 7% at 1×10−6 moll−1 concentration level. [Copyright &y& Elsevier]

Abstract: We investigated the effect of several K+ channel blockers on the antinociception induced by δ-opioid receptor agonist SNC80 using the paw pressure test, in which pain sensitivity is increased by an intraplantar injection (2 μg) of prostaglandin E2 (PGE2). Administration of SNC80 (20, 40 and 80 μg/paw) caused a decrease in the hyperalgesia induced by PGE2, in a dose-dependent manner. The possibility of higher dose of SNC80 (80 μg) causing a central or systemic effect was excluded since administration of the drug into the contralateral paw did not elicit antinociception in the right paw. Specific blockers of ATP-sensitive K+ channels, glibenclamide (20, 40 and 80 μg/paw) and tolbutamide (40, 80 and 160 μg/paw), antagonized the peripheral antinociception induced by SNC80 (80 μg). On the other hand, charybdotoxin (2 μg/paw), a large-conductance blocker of Ca2+-activated K+ channels, and dequalinium (50 μg/paw), a small conductance selective blocker of Ca2+-activated K+ channels, did not modify the effect of SNC80. This effect also remained unaffected by intraplantar administration of the voltage-dependent K+ channel blockers tetraethylammonium (30 μg/paw) and 4-aminopyridine (10 μg/paw), and of a non-specific K+ channel blocker, cesium (500 μg/paw). This study provides evidence that the peripheral antinociceptive effect of SNC80 result from the activation of ATP-sensitive K+ channels, and the other K+ channels are not involved. [Copyright &y& Elsevier]

Abstract: To assess the genetic consequences for a Neotropical tree of the loss of its main seed disperser, we compared the genetic structure of Inga ingoides in a site where the spider monkey (Ateles paniscus) was abundant and a site where it had been eliminated by subsistence hunting. Gene flow should be reduced in the site where the spider monkey is absent, and there should be a corresponding subpopulation differentiation of seedlings within the spatial range of the movements of these primates in the absence of between-site differences in allelic frequencies. At the microhabitat ( family) scale, seedlings growing under parent plants should be genetically more related in the absence of the spider monkey than in its presence. Subpopulation differentiation was smaller where the spider monkey was present ( four loci, FST = 0.011) than where it was absent ( four loci, FST = 0.053) for the first year of study, but not for the second year (three loci, FST = 0.005 vs. 0.003). The number of alleles in common among seedlings growing under parent plants was smaller in the presence of the spider monkey than in its absence, showing family genetic structure in the first generation for both years of study ( Mann-Whitney, z = -2.17, p = 0.03 and z = -2.72, p = 0.006 for 1996 and 1997, respectively). This family genetic structure in the first generation should accelerate the development of population genetic structure. Development of genetic structure might result in demographic changes, one of which would be a fitness reduction if the species were self-incompatible, as suggested for Inga by available evidence. Large birds and mammals are the main targets of subsistence hunting in the Neotropics. Extinction of seed-dispersing frugivores may result in pronounced changes in the demographic and genetic structure of tree species in Neotropical forests. [ABSTRACT FROM AUTHOR]

In various types of many-particle systems, bidispersity is frequently used to avoid spontaneous ordering in particle configurations. In this study, the relation between bidispersity and disorder degree of particle configurations is investigated. By using magnetic dipole–dipole interaction, magnet particles are dispersed in a two-dimensional cell without any physical contact between them. In this magnetic system, bidispersity is introduced by mixing large and small magnets. Then, the particle system is compressed to produce a uniform particle configuration. The compressed particle configuration is analyzed by using Voronoi tessellation for evaluating the disorder degree, which strongly depends on bidispersity. Specifically, the standard deviation and skewness of the Voronoi cell area distribution are measured. As a result, we find that the peak of standard deviation is observed when the numbers of large and small particles are almost identical. Although the skewness shows a non-monotonic behavior, a zero skewness state (symmetric distribution) can be achieved when the numbers of large and small particles are identical. In this ideally random (disordered) state, the ratio between pentagonal, hexagonal, and heptagonal Voronoi cells becomes roughly identical, while hexagons are dominant under monodisperse (ordered) conditions. The relation between Voronoi cell analysis and the global bond orientational order parameter is also discussed. [ABSTRACT FROM AUTHOR]

Lizard species have diverse behavioral and physiological responses to thermo-environmental conditions, which allow them to inhabit a broad range of latitudes and elevations. Because the availability of suitable thermal resources is limited and more variable at high-elevation environments than at lower elevations, we expect high-elevation lizards to be constrained in their thermoregulation relative to lizards at lower elevations by the fewer available thermal resources to reach optimal temperatures (colder environment). We studied the thermal biology of an endemic and Critically Endangered lizard, Liolaemus aparicioi, to assess its thermal responses along a 1000 m elevational gradient in La Paz Valley from May to August of 2015 (dry season). We took field body and microhabitat temperatures at capture sites (substrate and air above ground), and body size (snout-vent length and mass) of individuals at Taypichullo (3000 m asl), Gran Jardín de la Revolución Municipal Park (3500 m asl), and Taucachi (4000 m asl) localities. Operative temperatures were taken from calibrated models deployed in different available microhabitats. Preferred temperatures and thermal tolerance limits were determined in laboratory settings for lizards from each locality. Field body, microhabitat, and operative temperatures decreased with increasing elevation and differed between sexes. Lizards at the high elevation locality had the lowest thermoregulatory efficiency as compared with the mid and lower elevation localities. In laboratory measurements, while the preferred temperatures varied between sexes, pooled preferred temperatures and thermal tolerances were similar in all localities. Although thermal resources at high elevation can limit thermoregulatory possibilities in L. aparicioi , behavioral microhabitat use, time allocated to thermoregulation, and physiological adjustments seem to be possible strategies to counteract thermal costs along elevational gradients. • We studied the thermal biology of Liolaemus aparicioi along a 1000 m elevational gradient. • Field body temperatures tended to be lower with increasing elevation. • Sexes differed in body and preferred temperatures, and substrate temperature use. • CT min , T vol , T pant and CT max thermal parameters were similar along the gradient. • The effectiveness of thermoregulation was lower only at the high elevation locality. [ABSTRACT FROM AUTHOR]

Irazú and Turrialba are a twin volcanic complex that marks a distinct stop in volcanism along the Central America volcanic arc. We present a new traveltime velocity model of the crust beneath Irazú and Turrialba volcanoes, Costa Rica, and interpret it considering the results of previous ambient noise tomographic inversions. Data were acquired by a temporary seismic network during a period of low activity of the Irazú–Turrialba volcanic complex in 2018–2019. Beneath the Irazú volcano, we observe low P -wave velocities (V P = 5 km s−1) and low velocity ratios (V P/ V S = 1.6). In contrast, below the Turrialba volcano, we observe low S -wave velocities (V S = 3 km s−1) and a high V P/ V S (= 1.85) anomaly. We found that locations of low V P and V S anomalies (−15 %) correspond well with shear wave velocity anomalies retrieved from ambient noise tomography. At shallower depths, we observe high V P and V S anomalies (+15 %) located between the summits of the volcanoes. Subvertical velocity anomalies are also observed at greater depths, with high V P and V S anomalies appearing at the lower limits of our models. We propose a complex structure of an intermediate magmatic reservoir, presenting multiphase fluid states of a liquid-to-gas transition beneath Irazú and a juvenile store of magmatic fluid beneath Turrialba, while shallow fluid transport provides evidence of magmatic–hydrothermal interactions. [ABSTRACT FROM AUTHOR]

The saccharification of sugarcane bagasse by enzymatic hydrolysis is one of the most promising processes for obtaining fermentable sugar to be used in the production of second-generation ethanol. The objective of this work was to study the immobilization and stabilization of two commercial enzymes: Endocellulase (E-CELBA) in dextran coated iron oxide magnetic nanoparticles activated with aldehyde groups (DIOMNP) and β-glucosidase (E-BGOSPC) in glyoxyl agarose (GLA) so that their immobilized derivatives could be applied in the saccharification of pretreated sugarcane bagasse. This was the first time that the pretreated sugarcane bagasse was saccharified by cascade reaction using a endocellulase immobilized on dextran coated Fe2O3 with aldehyde groups combined with a β-glucosidase immobilized on glyoxyl agarose. Both enzymes were successfully immobilized (more than 60% after reduction with sodium borohydride) and presented higher thermal stability than free enzymes at 60, 70, and 80 °C. The enzymatic hydrolysis of the sugarcane bagasse was carried out with 15 U of each enzyme per gram of bagasse in a solid-liquid ratio of 1:20 for 48 h at 50 °C. Under these conditions, 39.06 ± 1.18% of the cellulose present in the pretreated bagasse was hydrolyzed, producing 14.11 ± 0.47 g/L of reducing sugars (94.54% glucose). In addition, DIOMNP endo-cellulase derivative maintained 61.40 ± 1.17% of its enzymatic activity after seven reuse cycles, and GLA β-glucosidase derivative maintained up to 58.20 ± 1.55% of its enzymatic activity after nine reuse cycles. [ABSTRACT FROM AUTHOR]

The main object of this paper is to develop an alternative construction for the bimodal skew-normal distribution. The construction is based upon a study of the mixture of skew-normal distributions. We study some basic properties of this family, its stochastic representations and expressions for its moments. Parameters are estimated using the maximum likelihood estimation method. A simulation study is carried out to observe the performance of the maximum likelihood estimators. Finally, we compare the efficiency of the new distribution with other distributions in the literature using a real data set. The study shows that the proposed approach presents satisfactory results. [ABSTRACT FROM AUTHOR]

We investigate the structural relaxation of a soft-sphere liquid quenched isochorically (ϕ = 0.7) and instantaneously to different temperatures Tf above and below the glass transition. For this, we combine extensive Brownian dynamics simulations and theoretical calculations based on the non-equilibrium self-consistent generalized Langevin equation (NE-SCGLE) theory. The response of the liquid to a quench generally consists of a sub-linear increase of the α-relaxation time with system's age. Approaching the ideal glass-transition temperature from above (Tf > Ta), sub-aging appears as a transient process describing a broad equilibration crossover for quenches to nearly arrested states. This allows us to empirically determine an equilibration timescale teq(Tf) that becomes increasingly longer as Tf approaches Ta. For quenches inside the glass (Tf ≤ Ta), the growth rate of the structural relaxation time becomes progressively larger as Tf decreases and, unlike the equilibration scenario, τα remains evolving within the whole observation time-window. These features are consistently found in theory and simulations with remarkable semi-quantitative agreement and coincide with those revealed in a previous and complementary study [P. Mendoza-Méndez et al., Phys. Rev. 96, 022608 (2017)] that considered a sequence of quenches with fixed final temperature Tf = 0 but increasing ϕ toward the hard-sphere dynamical arrest volume fraction ϕ H S a = 0.582. The NE-SCGLE analysis, however, unveils various fundamental aspects of the glass transition, involving the abrupt passage from the ordinary equilibration scenario to the persistent aging effects that are characteristic of glass-forming liquids. The theory also explains that, within the time window of any experimental observation, this can only be observed as a continuous crossover. [ABSTRACT FROM AUTHOR]

Storylines of Family Medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine as interpreted by individual family physicians and medical educators in the USA and elsewhere around the world. In 'X: standing up for diversity, equity and inclusion', authors address the following themes: 'The power of diversity--why inclusivity is essential to equity in healthcare', 'Medical education for whom?', 'Growing a diverse and inclusive workforce', 'Therapeutic judo--an inclusive approach to patient care', 'Global family medicine--seeing the world "upside down"', 'The inverse care law', 'Social determinants of health as a lens for care', 'Why family physicians should care about human rights' and 'Toward health equity--the opportunome'. May the essays that follow inspire readers to promote change. [ABSTRACT FROM AUTHOR]

A novel composite material based on acrylonitrile‐butadiene‐styrene (ABS) and carbon black (CB) was proposed here. Different ratios between CB and ABS (40 : 60–60 : 40 %, w/w) were studied to obtain a substrate with improved electrochemical properties. These materials were characterized by techniques such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), Raman and Fourier transform infrared (FT‐IR) spectroscopies and scanning electron microscopy (SEM). Under the CB/ABS substrate (50 : 50 %, w/w), a lower charge transfer resistance (854 Ω) and a higher heterogeneous electron transfer constant (K0=1.551×10−3 cm s−1) were found, indicating a kinetically more favorable reaction. To improve the electroanalytical performance of the CB/ABS electrode (50 : 50 %, w/w), silver nanoparticles (AgNPs) were electrodeposited using recycled silver from photographic waste, whose presence was confirmed by SEM imaging and Raman spectra. A method using square wave anodic stripping voltammetry (SWASV) and Pb2+ as model species was developed, where a wider linear working range (4.0 to 40.0 μg L−1) and lower detection limit (0.4 μg L−1) were achieved for the modified electrode. The electrode modification process was highly reproducible (RSD=9.7 %, n=9, inter‐electrode), with precise electrochemical responses (RSD=3.6 %, n=9, intra‐electrode). The applicability was demonstrated in two seawater samples, where recovery levels between 94 and 106 %, as well as statistically similar results to those obtained by atomic absorption spectroscopy, attested to the reliability of the analysis. Furthermore, it is noteworthy that an appropriate selectivity was achieved even in the presence of other metallic species. The proposed composite material is low‐cost, robust, versatile, and can be a promising tool for additive manufacturing of electrochemical sensors. [ABSTRACT FROM AUTHOR]

Anacondas, genus Eunectes, are a group of aquatic snakes with a wide distribution in South America. The taxonomic status of several species has been uncertain and/or controversial. Using genetic data from four recognized anaconda species across nine countries, this study investigates the phylogenetic relationships within the genus Eunectes. A key finding was the identification of two distinct clades within Eunectes murinus, revealing two species as cryptic yet genetically deeply divergent. This has led to the recognition of the Northern Green Anaconda as a separate species (Eunectes akayima sp. nov), distinct from its southern counterpart (E. murinus), the Southern Green Anaconda. Additionally, our data challenge the current understanding of Yellow Anaconda species by proposing the unification of Eunectes deschauenseei and Eunectes beniensis into a single species with Eunectes notaeus. This reclassification is based on comprehensive genetic and phylogeographic analyses, suggesting closer relationships than previously recognized and the realization that our understanding of their geographic ranges is insufficient to justify its use as a separation criterion. We also present a phylogeographic hypothesis that traces the Miocene diversification of anacondas in western South America. Beyond its academic significance, this study has vital implications for the conservation of these iconic reptile species, highlighting our lack of knowledge about the diversity of the South American fauna and the need for revised strategies to conserve the newly identified and reclassified species. [ABSTRACT FROM AUTHOR]

Purpose: The research aimed at investigating the pre-conditions and the decision-making process by which physician-entrepreneurs adopt CBHCS as part of their business. Method: The study uses the case method of investigation. Main results: Results showed that, in the cases studied, international experience and international networking are relevant characteristics of the physician-entrepreneur, besides country reputation, cultural and language similarities, and physician reputation. In addition, the decision processes of the physician-entrepreneurs in these organizations are based on an effectual logic. The offer of cross-border health care services was a combination of given means and contingencies, which helped the entrepreneurs to discover, or to create, the opportunity, and then develop it. Relevance/originality: The research combines the literatures on effectuation and inward internationalization to study the decision-making process of adopting CBHCS by medical clinics. Theoretical contributions: The study contributes to the literature by identifying certain pre-conditions and providing an in-depth analysis of the use of effectual logic by physician-entrepreneurs in their decision-making process of adopting CBHCS. [ABSTRACT FROM AUTHOR]

The impact of a spherical projectile on an evened-out granular bed generates a uniform ejecta of material and a crater with a raised circular rim. Recently, Sabuwala et al. [Phys. Rev. Lett. 120, 264501 (2018)] found that the uniform blanket of ejecta changes to a set of radial streaks when a spherical body impacts on an undulated granular surface, being a plausible explanation to the enigmatic ray systems on planetary bodies. Here, we show that ray systems can also be generated by the impact of nonspherical projectiles on a flat granular surface. This is a reasonable explanation considering that meteorites are rarely spherical. Moreover, by impacting bodies of different geometries, we show that the crater size follows the same power-law scaling with the impact energy found for spherical projectiles, and the crater rim becomes circular as the impact energy is increased regardless of the projectile shape, which helps to understand why most impact craters in nature are rounded. [ABSTRACT FROM AUTHOR]

This Rapid Communication reports on an experimental study of granular craters formed by a mechanism, namely, optical energy, via a pulsed laser focused onto the surface of a granular bed. This represents an insight into granular cratering for two reasons; first, there is no physical contact between the initiation mechanism and the granular media (as typical for impact or explosion craters). Second, the resulting craters are millimetric in scale, which facilitates a test of energy scalings down to a previously unobserved lengthscale. Indeed, we observe a range of energy scalings conforming to Dc∼Eβ with β≈0.31-0.43 depending on the characteristics of the granular media. [ABSTRACT FROM AUTHOR]

The accurate measurement of joint angles during patient rehabilitation is crucial for informed decision making by physiotherapists. Presently, visual inspection stands as one of the prevalent methods for angle assessment. Although it could appear the most straightforward way to assess the angles, it presents a problem related to the high susceptibility to error in the angle estimation. In light of this, this study investigates the possibility of using a new approach to angle calculation: a hybrid approach leveraging both a camera and LiDAR technology, merging image data with point cloud information. This method employs AI-driven techniques to identify the individual and their joints, utilizing the cloud-point data for angle computation. The tests, considering different exercises with different perspectives and distances, showed a slight improvement compared to using YOLO v7 for angle calculation. However, the improvement comes with higher system costs when compared with other image-based approaches due to the necessity of equipment such as LiDAR and a loss of fluidity during the exercise performance. Therefore, the cost–benefit of the proposed approach could be questionable. Nonetheless, the results hint at a promising field for further exploration and the potential viability of using the proposed methodology. [ABSTRACT FROM AUTHOR]

We used radio-telemetry to record how Caiman yacare (Cy) and Melanosuchus niger (Mn) responded to the intrusion of the Maniqui river into Cedral Lagoon in the Bolivian Amazon. Nine M. niger and 3 C. yacare were followed between December 2015 and May 2016. Both species showed a gradual reduction in mean monthly range from December (19.96 ha Mn and 1.74 ha Cy) to May 2016 (0.08 ha Mn and 0.24 ha Cy). Habitat use was fairly constant throughout the months for both species, Melanosuchus niger used mainly open swampy forests and Cyperaceae Marshes, while C. yacare used more islands and flooded grasslands. This study shows that both species of caimans responded to changes in depth and vegetation types, as their habitat as a whole was changed by river intrusion. [ABSTRACT FROM AUTHOR]

We report on an experimental investigation of craters generated by explosions at the surface of a model granular bed. Following the initial blast, a pressure wave propagates through the bed, producing high-speed ejecta of grains and ultimately a crater. We analyzed the crater morphology in the context of large-scale explosions and other cratering processes. The process was analyzed in the context of large-scale explosions, and the crater morphology was compared with those resulting from other cratering processes in the same energy range. From this comparison, we deduce that craters formed through different mechanisms can exhibit fine surface features depending on their origin, at least at the laboratory scale. Moreover, unlike laboratory-scale craters produced by the impact of dense spheres, the diameter and depth do not follow a 1/4-power-law scaling with energy, rather the exponent observed herein is approximately 0.30, as has also been found in large-scale events. Regarding the ejecta curtain of grains, its expansion obeys the same time dependence followed by shock waves produced by underground explosions. Finally, from experiments in a two-dimensional system, the early cavity growth is analyzed and compared to a recent study on explosions at the surface of water. [ABSTRACT FROM AUTHOR]

An intruder penetrating into a granular column experiences a depth-dependent friction force F(z). Different regimes of F(z) have been measured depending on the experimental design: a nearly linear dependence for shallow penetrations, total saturation at large depths, and an exponential increase when the intruder approaches the bottom of the granular bed. We report here an experiment that allows us to measure the different regimes in a single run during the quasistatic descent of a sphere in a light granular medium. From the analysis of the resistance in the saturation zone, it was found that F(z) follows a cube-power-law dependence on the intruder diameter and an exponential increase with the packing fraction of the bed. Moreover, we determine the critical mass mc required to observe infinite penetration and its dependence on the above parameters. Finally, we use our results to estimate the final penetration depth reached by intruders of masses m

When rough grains in loose packing conditions are discharged from a silo, a conical depression with a single slope is formed at the surface. We observed that the increase of volume fraction generates a more complex depression, characterized by two angles of discharge: one at the bottom similar to the angle of repose and a considerably larger upper angle. The change in slope appears at the boundary between a dense stagnant region at the periphery and the central flowing channel formed over the aperture. Since the material in the latter zone is always fluidized, the flow rate is unaffected by the initial packing of the bed. On the other hand, the contrast between both angles is markedly smaller when smooth particles of the same size and density are used, which reveals that high packing fraction and friction must combine to produce the observed geometry. Our results show that the surface profile helps to identify by simple visual inspection the packing conditions of a granular bed, being useful to prevent undesirable collapses during silo discharge in industry. [ABSTRACT FROM AUTHOR]

Energy efficiency is not only the most cost-effective way to reduce carbon dioxide emissions but also a way to improve competitiveness and create employment. EU aims to achieve nearly zero-energy (public) building (NZEB) by the end of 2018 (2020 for private buildings). This very ambitious target would be more easily fulfilled if high-performance thermal materials like phase change materials-PCMs are to be used. This paper reports experimental results on the properties of fly ash-based alkali-activated binder-AACB mortars in which a minor percentage of aggregates were replaced by PCMs. These include compression strength, at normal temperature and also at high temperatures, flexural strength, density, water absorption, unrestrained shrinkage as well as cost analysis. Several AACB mixtures showed an increase in compressive strength after being exposed to high temperatures. Since PCMs are made of flammable materials and AACB mortars show a much higher stability at high temperature than Portland cement-based mortars this means that AACB mortars are more suitable for PCM incorporation. This is a very important feature because flammable insulation materials were reported to be the cause of the recent Grenfell Tower fire tragedy that made 71 victims. [ABSTRACT FROM AUTHOR]

A cellular automaton model called the Firm Dynamics Model (FDM) is introduced to simulate the dynamics of firms within an economy. The model includes the growth of firms and their mergers and exits. The main objective is to compare the size-frequency distributions in the model with the empirical firm size distributions of several countries (USA, UK, Spain and Sweden). The empirical size distributions were assembled from business censuses and additional information on the country's largest companies in terms of the number of employees. For the four datasets analyzed here, the firm size distribution is compatible with a power law of the Pareto type with an exponent of close to two (for the probability density). For its part, the model delivers two different size-frequency distributions depending on the type of merger that firms can undergo: the friendly-merger version gives rise to subcritical distributions with an exponential tail, whereas the aggressive-merger version produces power-law distributions. The simulation model was run with underlying lattices in one, two and three dimensions in order to compare the simulated power-law exponent with the empirical one. The best agreement was obtained with the two-dimensional aggressive-merger model version, for which the power-law exponent is 2. 1 9 ± 0. 0 1 , as compared with an empirical exponent of 2. 1 ± 0. 1 (average over the four datasets). Further simulations with the model on a Bethe lattice confirm that the two-dimensional model provides the best fit to the empirical exponent. [ABSTRACT FROM AUTHOR]

Abstract Extensive Monte Carlo simulations are carried out in one, two and three dimensions for dynamic local load-sharing fiber bundle models following a power-law breaking rule with exponent ρ. This exponent controls the degree of disorder of the bundle. The results are obtained using two methods of introducing disorder in the simulations. In the standard, or classical, Monte Carlo method the disorder is quenched; in the second, or radioactive method the disorder is annealed. Both methods give identical mean time-to-failure values for systems of the same size. However, the radioactive method proves to be more efficient due to the smaller standard deviation of the probability distribution function of the time-to-failure. We take advantage of this efficiency to compute the asymptotic mean time-to-failure of large systems as a function of the degree of disorder, as parameterized by ρ. Based on these extensive simulations, conclusions are drawn regarding the upper critical dimension of time-dependent local load-sharing fiber bundle models. Highlights • Comparison of two Monte Carlo methods for time-dependent local load-sharing fiber bundle models. • Fibers follow a power-law breaking rule with exponent parameterizing disorder. • New radioactive Monte Carlo more efficient than the classical Monte Carlo. • Upper critical dimension seems to depend on the degree of disorder. • D = 2 is the upper critical dimension for high degrees of disorder. [ABSTRACT FROM AUTHOR]

In this study, we present a new family of distributions through generalization of the extended bimodal-normal distribution. This family includes several special cases, like the normal, Birnbaum-Saunders, Student’s t, and Laplace distribution, that are developed and defined using stochastic representation. The theoretical properties are derived, and easily implemented Monte Carlo simulation schemes are presented. An inferential study is performed for the Laplace distribution. We end with an illustration of two real data sets. [ABSTRACT FROM AUTHOR]

Force Sensing Resistors (FSRs) exhibit considerable amounts of hysteresis and repeatability error inhibiting their usage in applications that require high-accurate force readings. This paper presents the hysteresis characterization and modeling of the Tekscan A201-1 FSR employing the Preisach Operator (PO) function. In order to compensate for hysteresis during sensor operation, the inverse PO was numerically found on the basis of the Closest Match Algorithm (CMA). A test bench, capable of handling sixteen sensors simultaneously, was built, which allowed the characterization and later testing of the CMA. Grip force profiles were applied to the sensors during testing and the experimental results showed a considerable reduction in the force estimation error compared with the linear regression method proposed by the manufacturer. These results enable a wider use of FSRs in applications with tight accuracy requirements. Finally, a generalized sensor model for hysteresis compensation that simplifies the obtaining of PO parameters is presented. [ABSTRACT FROM AUTHOR]

Wireless communications, involving electronic devices, are increasingly important Performance is a fundamental issue, leading to more reliable and efficient communications. Security is also most important. Laboratory measurements were performed about several performance aspects of Wi-Fi IEEE 802.11a 54 Mbps Open links. Our study contributes to performance evaluation of this technology, using available equipments (HP V-M200 access points and Linksys WPC600N adapters). New detailed results are given, namely at OSI level 4, from TCP and UDP experiments. TCP throughput is measured versus TCP packet length. Jitter and percentage datagram loss are measured versus UDP datagram size. Results are compared for point-to-point, point-to-multipoint and four-node point-to-multipoint links. Conclusions are drawn about performance of the links. [ABSTRACT FROM AUTHOR]

The flow rate of water through an orifice at the bottom of a container depends on the hydrostatic pressure whereas for a dry granular material it is nearly constant. But what happens during the simultaneous discharge of grains and liquid from a silo? By measuring the flow rate as a function of time, we found that (i) different regimes appear, going from the constant flow rate to a hydrostatic-like discharge depending on the aperture size and grain diameter, (ii) the mixed material is always discharged faster than dry grains but slower than liquid, (iii) for the mixture, the liquid level drops faster than the grain level, but they are always linearly proportional to one another, and (iv) a sudden growth in the flow rate happens during the transition from a biphasic discharge to a single phase discharge. These results are associated to the competition between the decrease in hydrostatic pressure above the granular bed and the hydrodynamic resistance. A model combining Darcy’s law with Bernoulli and mass conservation equations is proposed, and the numerical results are in good agreement with experiments. [ABSTRACT FROM AUTHOR]

Carbon dioxide sequestration is crucial for targets for limiting global warming could be achieved. This paper discloses results of an investigation concerning the performance of fly ash/waste glass alkaline-based mortars with recycled aggregates reinforced by hemp fibres exposed to accelerated carbon dioxide curing. Compressive strength, freeze-thaw resistance, carbon footprint and cost were studied. The results show that hemp fibres lead to a reduction of mechanical properties of alkali-activated materials. A high correlation was found between compressive and flexural strength. The results also show that accelerated curing provides a high carbon sequestration. Furthermore, the use of at least 8% hemp fibres leads to carbon negative emissions −19.7 kgCO 2 eq/m 3 for fly ash/waste glass alkaline-based mortars with recycled aggregates based composites. [ABSTRACT FROM AUTHOR]

Lowe Syndrome (LS) is a condition due to mutations in the OCRL1 gene, characterized by congenital cataracts, intellectual disability, and kidney malfunction. Unfortunately, patients succumb to renal failure after adolescence. This study is centered in investigating the biochemical and phenotypic impact of patient's OCRL1 variants (OCRL1VAR). Specifically, we tested the hypothesis that some OCRL1VAR are stabilized in a non-functional conformation by focusing on missense mutations affecting the phosphatase domain, but not changing residues involved in binding/catalysis. The pathogenic and conformational characteristics of the selected variants were evaluated in silico and our results revealed some OCRL1VAR to be benign, while others are pathogenic. Then we proceeded to monitor the enzymatic activity and function in kidney cells of the different OCRL1VAR. Based on their enzymatic activity and presence/absence of phenotypes, the variants segregated into two categories that also correlated with the severity of the condition they induce. Overall, these two groups mapped to opposite sides of the phosphatase domain. In summary, our findings highlight that not every mutation affecting the catalytic domain impairs OCRL1′s enzymatic activity. Importantly, data support the inactive-conformation hypothesis. Finally, our results contribute to establishing the molecular and structural basis for the observed heterogeneity in severity/symptomatology displayed by patients. [ABSTRACT FROM AUTHOR]

The article describes observations of the habitat use of a juvenile Bothrops atrox or Lancehead that was found sitting on top of a leaf of Eichornia species in the Tacana Indigenous Territory, La Paz Department, Bolivia on March 2, 2021.

The Roadmap to a Resource Efficient Europe aims that by 2020, waste will be managed as a resource. Thus materials that have the ability for the reuse of several types of wastes, such as alkali-activated cement-based binders (AACBs), will merit special attention. Some wastes like fly ash deserve special attention because they are generated in high amounts and have a very low reuse rate. This paper reports experimental results regarding the influence of the mix design of fly ash and waste glass AACB mortars containing two different biopolymers (carrageenan and xanthan) on their short-term mechanical performance. Microstructure and cost analysis are also included. The results show that a mixture of 80% fly ash, 10% waste glass, and 10% calcium hydroxide activated with an alkaline activator has the highest compressive strength. The results also show that the mortars with minor biopolymer carrageenan content are associated with a relevant increase in compressive strength and that the use of 0.1% of carrageenan leads to optimum compressive strength in most mixtures. The use of xanthan shows no beneficial effects on the compressive strength of AACB mortars. Several mixtures with xanthan even show a reduction in the compressive strength. [ABSTRACT FROM AUTHOR]