Gas dissolution foaming as a novel approach for the production of lightweight biocomposites of PHB/natural fibre fabrics

Producción CientíficaThe aim of this study is to propose and explore a novel approach for the production of cellular lightweight natural fibre, nonwoven, fabric-reinforced biocomposites by means of gas dissolution foaming from composite precursors of polyhydroxybutyrate-based matrix and flax fabric reinforcement. The main challenge is the development of a regular cellular structure in the polymeric matrix to reach a weight reduction while keeping a good fibre-matrix stress transfer and adhesion. The viability of the process is evaluated through the analysis of the cellular structure and morphology of the composites. The effect of matrix modification, nonwoven treatment, expansion temperature, and expansion pressure on the density and cellular structure of the cellular composites is evaluated. It was found that the nonwoven fabric plays a key role in the formation of a uniform cellular morphology, although limiting the maximum expansion ratio of the composites. Cellular composites with a significant reduction of weight (relative densities in the range 0.4–0.5) were successfully obtained.Ministerio de Educación y Formación Profesional (grants FPU12/05869 and EST14/00273)Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (grants BIA2014-59399-R and MAT2015-69234-R)Junta de Castilla y Leon (grant VA011U16

Loss-of-rescue of Ryr1I4895T-related pathology by the genetic inhibition of the ER stress response mediator CHOP

RYR1 is the gene encoding the ryanodine receptor 1, a calcium release channel of the endo/sarcoplasmic reticulum. I4898T in RYR1 is one of the most common mutations that give rise to central core disease (CCD), with a variable phenotype ranging from mild to severe myopathy to lethal early-onset core-rod myopathy. Mice with the corresponding I4895T mutation in Ryr1 present mild myopathy when the mutation is heterozygous while I4895T homozygous is perinatal-lethal. Here we show that skeletal muscles of I4895T homozygous mice at birth present signs of stress of the endoplasmic reticulum (ER stress) and of the related unfolded protein response (UPR) with increased levels of the maladaptive mediators CHOP and ERO1. To gain information on the role of CHOP in the pathogenesis of RYR1I4895T-related myopathy, we generated compound Ryr1I4895T, Chop knock-out (-/-) mice. However, the genetic deletion of Chop, although it attenuates ER stress in the skeletal muscle of the newborns, does not rescue any phenotypic or functional features of Ryr1I4895T in mice: neither the perinatal-lethal phenotype nor the inability of Ryr1I4895T to respond to its agonist caffeine, but protects from ER stress-induced apoptosis. These findings suggest that genetic deletion of the ER stress response mediator CHOP is not sufficient to counteract the pathological Ryr1I4895T phenotype

Red valerian (Centranthus ruber L.): wild host of Cucumber mosaic virus in uncultivated areas of Campania region (Southern Italy)

In spring 2009‒2010, red valerian plants (Centranthus ruber L.) showing stunting, mild leaf vein mosaic, reduction in size of leaves and flowers and occasional deformation and reduction of the number of leaves, were observed in Campania (Southern Italy). The presence of Cucumber mosaic virus (CMV) in the diseased plants was demonstrated by the reactions of test plants, electron microscopy, serology and RT-PCR. On the basis of highest identities and closest phylogenetic relationships, CMV from C. ruber was most closely related to CMV subgroup I A. Koch’s postulates were fulfilled by back-inoculating healthy C. ruber seedlings

Oct-4 is highly expressed in stem/progenitor cells and in primordial follicles of the fetal human ovary

Oct-4 (Octamer-binding transcription factor 4) is a member of the POU (Pit-Oct-Unc) family. During development, Oct-4 is expressed in embryonic stem cells and in germ cell precursors. In this study, we investigated the expression of Oct-4 in the ovaries of human fetuses during gestation. The ovaries of 14 human fetuses and newborns, ranging in gestational age from 12 up to 38 weeks of gestation, were formalin-fixed, routinely processed and paraffin-embedded. Paraffin sections were immunostained with an anti-Oct-4 commercial antibody. Oct-4 expression was demonstrated in all the ovaries analyzed. Immunoreactivity for Oct-4 was detected in multiple stem/progenitor cells, including oogonia. Moreover, Oct-4 was expressed in oocytes, in primordial follicles. In ovarian stem/progenitor cells, Oct-4 was expressed in the nucleus, whereas in oocytes reactivity for Oct-4 was restricted to the cytoplasm. In the initial stages of gestation, the majority of Oct-4-positive precursor cells were detected in the external cortex. These preliminary data indicate Oct-4 as a major player in germ cell differentiation in the human ovary and as a useful marker for ovarian stem/progenitor cells. Given the ability of Oct-4 for the detection of ovarian stem/progenitor cells, further studies are needed in order to verify its ability to detect stem cells in adult ovaries

ISL-1: a new potential marker of stem/progenitor cells in the developing human uterus

The human uterus is a highly dynamic organ with peculiar plasticity and marked reproductive ability, due to the presence of a vast number of multiple stem/progenitor cell types, including endometrial, stromal and vascular progenitor cells. Conflicting results have been published regarding which uterine population might represent the real stem/progenitor cell fraction in terms of in vivo stem cell activity. Human endometrial side population (ESP) cells were shown to differentiate into multiple endometrial lineages in the stem cell niche provided by whole endometrial cells, suggesting that ESP cells might represent the most important stem/progenitor cells responsible of the cyclical regeneration of the endometrium throughout a woman’s reproductive life. This study was aimed at analyzing the localization, composition, and occurrence of stem cell niches in the human fetal uterus at different stages of development. To this end, the whole uterus was obtained at autopsy by 12 human fetuses and newborns, ranging in gestational age from 12 up to 39 weeks of gestation. Tissue paraffin sections were immunostained with antibodies against insulin gene enhancer protein (ISL-1), a transcription factor previously utilized as a marker of stem/progenitor cells in the pancreas, heart and nervous system. Reactivity for ISL-1 was detected in both epithelial and stromal uterine precursors, at all gestational ages, allowing the detection of uterine progenitor cells. The loss of reactivity for ISL-1 in some stromal cell precursors was interpreted as a sign of differentiation. These preliminary data indicate ISL-1 as a useful marker for the detection of stem/progenitor cells in the human fetal endometrium. Further studies are needed to verify the utility of ISL-1 as a marker of stem/progenitor cells in the adult endometrium

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Loss-of-rescue of Ryr1 I4895T-related pathology by the genetic inhibition of the ER stress response mediator CHOP

Abstract RYR1 is the gene encoding the ryanodine receptor 1, a calcium release channel of the endo/sarcoplasmic reticulum. I4898T in RYR1 is one of the most common mutations that give rise to central core disease (CCD), with a variable phenotype ranging from mild to severe myopathy to lethal early-onset core-rod myopathy. Mice with the corresponding I4895T mutation in Ryr1 present mild myopathy when the mutation is heterozygous while I4895T homozygous is perinatal-lethal. Here we show that skeletal muscles of I4895T homozygous mice at birth present signs of stress of the endoplasmic reticulum (ER stress) and of the related unfolded protein response (UPR) with increased levels of the maladaptive mediators CHOP and ERO1. To gain information on the role of CHOP in the pathogenesis of RYR1I4895T-related myopathy, we generated compound Ryr1 I4895T, Chop knock-out (-/-) mice. However, the genetic deletion of Chop, although it attenuates ER stress in the skeletal muscle of the newborns, does not rescue any phenotypic or functional features of Ryr1 I4895T in mice: neither the perinatal-lethal phenotype nor the inability of Ryr1 I4895T to respond to its agonist caffeine, but protects from ER stress-induced apoptosis. These findings suggest that genetic deletion of the ER stress response mediator CHOP is not sufficient to counteract the pathological Ryr1 I4895T phenotype

Study of aerodynamic performances of different wind tunnel configurations and air inlet velocities, using computational fluid dynamics (CFD)

Livestock and agricultural activities contribute significantly to atmospheric ammonia emission in Europe. The volatilization process depends on many factors, especially wind speed and rainfall. The most important methods to evaluate ammonia volatilization are the wind tunnel and micrometeorological methods. The tunnels are more flexible and simple to use in every situation. Few studies have been carried out to determine, which conditions are established inside the chamber and how they influence the ammonia volatilization and measurement. The aim of this research was to investigate the effects of the wind tunnel configuration and flow inlet velocity, by means of CFD simulations and wind speed measurements, in order to achieve a better aerodynamic performance. The SST k–ω model used for simulations was first validated in order to prove the consistency of the model itself. Several configurations were simulated and compared. In particular, in order to overcome the asymmetric flow conditions that occurred in all wind tunnel configurations, four flow distribution devices were proposed and simulated. The best setup was chosen with the purpose of reaching both the best uniform velocity distribution (to ensure homogeneous volatilization from the emitting surface) and easy transport for field applications. It consists of an emission chamber 40 cm wide, 25 cm high and 80 cm long, situated between a divergent diffuser and a convergent duct, respectively 50 cm and 25 cm long. Moreover, structures similar to honeycombs, namely guiding channels, were introduced in the divergent diffuser, because they showed the best aerodynamic performance. These 20 channels, located in the divergent diffuser, prevent flow from separating, by means of the reduction of the expansion angle, obtaining the desired flow conditions inside the wind tunnel. Finally, it was verified that CFD confirmed its usefulness as a decision-support instrument to design and simulate possible solutions, reducing design time