Characterisation of agricultural residues used as a source of fibres for fibre-cement production

Nowadays, certain components of non-wood annual plants such as corn stalk and industrial hemp core are considered waste materials or used in low value applications; both by-products have a very low cost. On the other hand, given the large quantities of these materials generated worldwide and their renewable character, it is reasonable to explore new routes for their exploitation. The aim of this paper is to study the potential of both corn stalk (Zea Mays L.) and industrial hemp core (Cannabis Sativa L.) fibres as a renewable source of cellulose fibres in the production of fibre-cement. For each source of fibres, a number of chemical cooking treatments were studied. The morphological properties of the fibres were determined using a scanning electron microscope and a fibre and pulp morphological analyser. Pulp refining was carried out in a PFI mill to improve the characteristics of the fibres. In the case of corn fibres, different degrees of refining were applied. The fibre flocculation process was investigated using several polyacrylamides. The process was studied by monitoring the chord size distribution in real time by means of a focused beam reflectance measurement probe. The results indicated both pulps can be used for the production of fibre-cement, having the two types of pulp morphological similarities with the pine fibres currently used. Through the flocculation process it was concluded the floc size depends on the length of the fibres

Ecomorphological characterization of murines and non-arvicoline cricetids (Rodentia) from south-western Europe since the latest Middle Miocene to the Mio-Pliocene boundary (MN 7/8-MN13)

SUBVENCIÓ: Universidad Complutense de Madrid: BOUC UCM 17-5-2016 (CT27 / 16-CT28 / 16)Rodents are the most speciose group of mammals and display a great ecological diversity. Despite the greater amount of ecomorphological information compiled for extant rodent species, studies usually lack of morphological data on dentition, which has led to difficulty in directly utilizing existing ecomorphological data of extant rodents for paleoecological reconstruction because teeth are the most common or often the only micromammal fossils. Here, we infer the environmental ranges of extinct rodent genera by extracting habitat information from extant relatives and linking it to extinct taxa based on the phenogram of the cluster analysis, in which variables are derived from the principal component analysis on outline shape of the upper first molars. This phenotypic ''bracketing'' approach is particularly useful in the study of the fossil record of small mammals, which is mostly represented by isolated teeth. As a case study, we utilize extinct genera of murines and non-arvicoline cricetids, ranging from the Iberoccitanian latest middle Miocene to the Mio-Pliocene boundary, and compare our results thoroughly with previous paleoecological reconstructions inferred by diferent methods. The resultant phenogram shows a predominance of ubiquitous genera among the Miocene taxa, and the presence of a few forest specialists in the two rodent groups (Murinae and Cricetidae), along with the absence of open environment specialists in either group of rodents. This appears to be related to the absence of enduring grassland biomes in the Iberian Peninsula during the late Miocene. High consistency between our result and previous studies suggests that this phenotypic ''bracketing'' approach is a very useful tool

Effect of population density on size of edible snail helix aspersa müller

An assessment was made of the effects of population density on Helix aspersa Müller snails at their nursery stage. A sample of 3420 animals was used, grouped at eighteen density levels: from 600 to 11100 snails/m2. The results demonstrate that higher population density decreased growth (p<0.001). Furthermore the optimum snail population density at the nursery stage ranged from 600 to 4300 snails/m2.Se estudia el efecto de la densidad sobre el tamaño del Helix aspersa Müller durante la primera fase de crecimiento. Se utilizan 18 niveles de densidad entre 600 a 11100 animales/m2. Los resultados indican la existencia de diferencias significativas en el crecimiento según el nivel de densidad (p<0,001), de modo que a medida que se incrementa la densidad disminuye el tamaño. La densidad óptima, en primera edad, oscila entre 600 y 4300 animales/m2

Role of the microtubule-targeting drug vinflunine on cell-cell adhesions in bladder epithelial tumour cells

Background: Vinflunine (VFL) is a microtubule-targeting drug that suppresses microtubule dynamics, showing anti-metastatic properties both in vitro and in living cancer cells. An increasing body of evidence underlines the influence of the microtubules dynamics on the cadherin-dependent cell-cell adhesions. E-cadherin is a marker of epithelial-to-mesenchymal transition (EMT) and a tumour suppressor; its reduced levels in carcinoma are associated with poor prognosis. In this report, we investigate the role of VFL on cell-cell adhesions in bladder epithelial tumour cells. Methods: Human bladder epithelial tumour cell lines HT1376, 5637, SW780, T24 and UMUC3 were used to analyse cadherin-dependent cell-cell adhesions under VFL treatment. VFL effect on growth inhibition was measured by using a MTT colorimetric cell viability assay. Western blot, immunofluorescence and transmission electron microscopy analyses were performed to assess the roles of VFL effect on cell-cell adhesions, epithelial-to-mesenchymal markers and apoptosis. The role of the proteasome in controlling cell-cell adhesion was studied using the proteasome inhibitor MG132. Results: We show that VFL induces cell death in bladder cancer cells and activates epithelial differentiation of the remaining living cells, leading to an increase of E-cadherin-dependent cell-cell adhesion and a reduction of mesenchymal markers, such as N-cadherin or vimentin. Moreover, while E-cadherin is increased, the levels of Hakai, an E3 ubiquitin-ligase for E-cadherin, were significantly reduced in presence of VFL. In 5637, this reduction on Hakai expression was blocked by MG132 proteasome inhibitor, indicating that the proteasome pathway could be one of the molecular mechanisms involved in its degradation. Conclusions: Our findings underscore a critical function for VFL in cell-cell adhesions of epithelial bladder tumour cells, suggesting a novel molecular mechanism by which VFL may impact upon EMT and metastasis

Exploring the Water-Binding Pocket of the Type II Dehydroquinase Enzyme in the Structure-Based Design of Inhibitors

Structural and computational studies to explore the WAT1 binding pocket in the structure-based design of inhibitors against the type II dehydroquinase (DHQ2) enzyme are reported. The crystal structures of DHQ2 from M. tuberculosis in complex with four of the reported compounds are described. The electrostatic interaction observed between the guanidinium group of the essential arginine and the carboxylate group of one of the inhibitors in the reported crystal structures supports the recently suggested role of this arginine as the residue that triggers the release of the product from the active site. The results of the structural and molecular dynamics simulation studies revealed that the inhibitory potency is favored by promoting interactions with WAT1 and the residues located within this pocket and, more importantly, by avoiding situations where the ligands occupy the WAT1 binding pocket. The new insights can be used to advantage in the structure-based design of inhibitorsFinancial support from the Spanish Ministry of Science and Innovation (Grant SAF2010-15076) and the Xunta de Galicia (Grant GRC2013/041) is gratefully acknowledged. B.B. and A.P. thank the Spanish Ministry of Education for their respective FPU fellowships. A.S. thanks the Spanish Ministry of Economy and Competitiveness for her FPI fellowship. J.M.O. thanks the Xunta de Galicia for a Plan I2C postdoctoral fellowshipS

Unveiling the post-pandemic hybrid education: Students' and professors' perspectives on the contingent virtual education modality

Se realiza un diseño mixto paralelo-convergente para evaluar el impacto de la “pedagogía pandémica” en profesores y estudiantes. Mediante encuestas en línea y entrevistas en profundidad se identifica que la mayoría de los educadores informan una competencia media a alta en tecnología, organización y gestión de estudiantes, así como estresores relacionados con el impacto de la educación virtual en su calidad de vida. Los estudiantes experimentan fatiga física, aburrimiento, agotamiento y pasividad. Las entrevistas revelan las aspiraciones de los educadores para abordar estos desafíos, asegurar un mejor apoyo administrativo y fortalecer la gestión pedagógica. La pedagogía pandémica muestra retos para el aprendizaje y oportunidades de cambios transformadores para la educación en enfermería.This study used a mixed parallel-convergent typology design to assess the impact of “pandemic pedagogies” on professors and students. Online surveys and in-depth interviews Survey findings showed that most educators reported medium to high competence in technology, organizational and student management, alongside stressors related to virtual education's impact on their quality of life. Similarly, students experienced physical fatigue, boredom, exhaustion, and passivity. Interviews revealed educators' aspirations to address these challenges, secure enhanced administrative support, and strengthen pedagogical management. Pandemic pedagogies revealed learning challenges and opportunities for transformative changes in nursing education across all levels

Habitat selection in terrestrial snails and its applications to heliciculture

Snails are employed as experimental animals in different scientific fields and their growth is a good biological indicator. Growth is mainly determined at a genetic level, although many factors biotic and abiotic may alter growth rates. One of these factors is habitat selection. Nevertheless the knowledge about the cha-racteristics that determines habitat selection are not considered in the design of installations, management of farms or raising snails. In this way, the aim of this paper is synthesize the different components of habitat that influence habitat choice of terrestrial snails. On the other hand, it proposes premises that would be considered in design of installations.El crecimiento de los caracoles terrestres que, además de como animales productivos, se utilizan como animales de experimentación es considerado un buen indicador biológico. Aunque el crecimiento está genéticamente determinado, muchos factores pueden modificarlo, uno de ellos es la selección de hábitat. Sin embargo, los conocimientos sobre las condiciones que la determinan no se suelen incorporar al diseño de instalaciones, manejo de los criaderos o la producción helicícola. En este trabajo se revisan aquellas condiciones que determinan la selección de microhábitat en caracoles terrestres y se proponen medidas que deberían ser consideradas en el diseño de instalaciones

Continuous‑wavelet‑transform analysis of the multifocal ERG waveform in glaucoma diagnosis

The vast majority of multifocal electroretinogram (mfERG) signal analyses to detect glaucoma study the signals’ amplitudes and latencies. The purpose of this paper is to investigate application of wavelet analysis of mfERG signals in diagnosis of glaucoma. This analysis method applies the continuous wavelet transform (CWT) to the signals, using the real Morlet wavelet. CWT coefficients resulting from the scale of maximum correlation are used as inputs to a neural network, which acts as a classifier. mfERG recordings are taken from the eyes of 47 subjects diagnosed with chronic open-angle glaucoma and from those of 24 healthy subjects. The high sensitivity in the classification (0.894) provides reliable detection of glaucomatous sectors, while the specificity achieved (0.844) reflects accurate detection of healthy sectors. The results obtained in this paper improve on the previous findings reported by the authors using the same visual stimuli and database.Ministerio de Ciencia e Innovació

Improved measurement of intersession latency in mfVEPs

Purpose: The purpose of the study is to present a method (Selfcorr) by which to measure intersession latency differences between multifocal VEP (mfVEP) signals. Methods: The authors compared the intersession latency difference obtained using a correlation method (Selfcorr) against that obtained using a Template method. While the Template method cross-correlates the subject’s signals with a reference database, the Selfcorr method cross-correlates traces across subsequent recordings taken from the same subject. Results: The variation in latency between intersession signals was 0.8 ± 13.6 and 0.5 ± 5.0 ms for the Template and Selfcorr methods, respectively, with a coefficient of variability C V_TEMPLATE = 15.83 and C V_SELFCORR = 5.68 (n = 18, p = 0.0002, Wilcoxon). The number of analyzable sectors with the Template and Selfcorr methods was 36.7 ± 8.5 and 45.3 ± 8.7, respectively (p = 0.0001, paired t test, two tailed). Conclusions: The Selfcorr method produces smaller intersession mfVEP delays and variability over time than the Template method.Ministerio de Ciencia e Innovació

Simulación de manejo integrado de malezas: sistema Euphorbia davidii – Soja

Se presenta una aplicación de un modelo de simulación cultivo-maleza que permite comparar y evaluar estrategias de Manejo Integrado de Malezas. Específicamente el modelo fue parametrizado para el cultivo de soja en competencia con Euphorbia davidii. Se utilizó la información demográfica de la maleza y del cultivo relevada a campo en la zona centro de la provincia de Buenos Aires, a lo largo de 2 ciclos de cultivo (2011/2012 y 2013/2014). El modelo se sometió a un proceso de calibración y posterior validación con 70 y 30% de las observaciones respectivamente (N=37). Se generaron 2 casos anuales con el objetivo de demostrar las prestaciones del modelo y se comparó el efecto de diversas estrategias de manejo, evaluando rendimiento, competencia, resultado económico e impacto ambiental. En uno de los casos analizados se observa que las medidas de manejo cultural podrían disminuir 46% la competencia interespecífica y 40% la producción de semillas, aumentando 6% el rendimiento esperado y 44 US$.ha⁻¹ el margen bruto, para niveles similares de impacto ambiental.Sociedad Argentina de Informática e Investigación Operativ