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Northwest Africa 5790. Top Sequence of the Nakhlite Pile
NWA 5790 is a recently discovered nakhlite. Its mineralogy, petrology and geochemistry suggest that it is the topmost sequence of the nakhlite lava pile
Genesis of an atypical Podzol in the Iberian Range: micromorphological characterization
A podzol has been described in the Iberian Range (Moncayo Natural Park), which may represent the southernmost example in Europe. The fact that it occurs at the podzol distribution limit makes its morphology atypical. The aim of this work is to identify the components and formation processes of the soil, and to determine if the processes are active or paleo-processes by a micromorphological approach. The study podzol is located in the top of a northern hillside (30% of slope), at 1600 m altitude on quartzitic sandstones, under Scots pine (Pinus sylvestris) with an udic moisture regime and a frigid temperature regime. We found opaque, orthic iron oxide nodules at the base of the profile (Bhs1), which is related to a current oxidation-reduction process; silt caps are also observed on the coarse elements, pedofeatures evidencing the cryoturbation process, probably also current processes. In the Bhs2 horizon, coatings and micro-laminated clay infillings are identified that are interspersed with fine silts in the holes. Many of these coatings are fragmented and mixed with the basal mass of the soil, indicating that they are paleofeature, possibly prior to the current podzolization.
En el Sistema Ibérico (Parque Natural del Moncayo) han sido descritos Podzols, que se encuentran entre los más meridionales de Europa. El hecho de estar en su lÃmite de distribución hace que su morfologÃa sea atÃpica. El objetivo de este trabajo es identificar los componentes y procesos de formación del suelo, y determinar si los procesos son activos o paleo-procesos, mediante un enfoque micromorfológico. El Podzol de estudio está situado en la cima de una ladera septentrional (30% de pendiente), a 1600 m de altitud sobre areniscas cuarcÃticas, bajo pino silvestre (Pinus sylvestris) con un régimen de humedad údico y un régimen de temperatura frÃgido. Se encuentran nódulos opacos, órticos, de óxidos de hierro en la base del perfil (horizonte Bhs1), lo que está relacionado con un proceso de óxido-reducción actual; también se observan casquetes o cappings de limo en los elementos gruesos, edaforrasgo que evidencia el proceso de crioturbación, probablemente también actual. En el horizonte Bhs2 se identifican revestimientos y rellenos de arcilla microlaminada que se intercalan con limos finos en los poros. Muchos de estos revestimientos están fragmentados y mezclados con la masa basal del suelo, lo que indica que son paleoprocesos, posiblemente anteriores a la podzolización actual
Radiogenomics in clear cell renal cell carcinoma: correlations between advanced CT imaging (texture analysis) and microRNAs expression
Purpose: A relevant challenge for the improvement of clear cell renal cell carcinoma management could derive from the identification of novel molecular biomarkers that could greatly improve the diagnosis, prognosis, and treatment choice of these neoplasms. In this study, we investigate whether quantitative parameters obtained from computed tomography texture analysis may correlate with the expression of selected oncogenic microRNAs. Methods: In a retrospective single-center study, multiphasic computed tomography examination (with arterial, portal, and urographic phases) was performed on 20 patients with clear cell renal cell carcinoma and computed tomography texture analysis parameters such as entropy, kurtosis, skewness, mean, and standard deviation of pixel distribution were measured using multiple filter settings. These quantitative data were correlated with the expression of selected microRNAs (miR-21-5p, miR-210-3p, miR-185-5p, miR-221-3p, miR-145-5p). Both the evaluations (microRNAs and computed tomography texture analysis) were performed on matched tumor and normal corticomedullar tissues of the same patients cohort. Results: In this pilot study, we evidenced that computed tomography texture analysis has robust parameters (eg, entropy, mean, standard deviation) to distinguish normal from pathological tissues. Moreover, a higher coefficient of determination between entropy and miR-21-5p expression was evidenced in tumor versus normal tissue. Interestingly, entropy and miR-21-5p show promising correlation in clear cell renal cell carcinoma opening to a radiogenomic strategy to improve clear cell renal cell carcinoma management. Conclusion: In this pilot study, a promising correlation between microRNAs and computed tomography texture analysis has been found in clear cell renal cell carcinoma. A clear cell renal cell carcinoma can benefit from noninvasive evaluation of texture parameters in adjunction to biopsy results. In particular, a promising correlation between entropy and miR-21-5p was found
Proadrenomedullin NH(2)-terminal 20 peptide (PAMP) and adrenomedullin bind to teratocarcinoma cells.
Proadrenomedullin NH(2-)terminal 20 peptide (PAMP) and adrenomedullin (ADM) bind to teratocarcinoma cells. The effects of PAMP and ADM on teratocarcinoma cells were investigated. (125)I-PAMP bound to PA1 cells with moderate affinity (K(d) = 110 nM) to a single class of sites (B(max) = 110 000/cell). Specific (125)I-PAMP binding was inhibited by PAMP (IC(50) of 100 nM) but not ADM, calcitonin gene-related peptide (CGRP), or amylin. Specific (125)I-ADM binding was inhibited with high affinity by ADM, CGRP, and CGRP(8-37) (IC(50) values of 10, 10, and 15 nM respectively) but not PAMP or amylin. ADM elevated cAMP (ED(50) value of 100 nM), whereas PAMP had no effect on basal cAMP but inhibited the increase in cAMP caused by 10 nM ADM. Also, the increase in cAMP caused by ADM was inhibited CGRP(8-37), suggesting that ADM is binding to CGRP receptors. ADM (100 nM) stimulated transiently c-fos mRNA, whereas PAMP (1000 nM) had little effect; however, PAMP inhibited the increase in c-fos mRNA caused by ADM. ADM stimulated [(3)H]thymidine uptake into PA1 cells, whereas PAMP inhibited the increase in thymidine uptake caused by ADM. These results indicate that ADM and PAMP are both biologically active in teratocarcinoma cells
A study on EEG power and connectivity in a virtual reality bimanual rehabilitation training system
The study of neural processes that describe
bimanual activity in areas such as neurology and rehabilitation
are of high interest, in particular for rehabilitation after brain
injury. However, brain processes during bimanual motor
rehabilitation are not fully understood during stroke
rehabilitation. Hence, it is not clear how to exploit them and their
possible advantages in an EEG driven Virtual Reality (VR)
training. In this work, VR and EEG were combined to study the
neural processes in motor areas during bimanual activity in a
serious game, involving two kind of movements: Left to Right
(L2R) movement (Right handle forward and Left handle
backward movements) and Right to Left (R2L) movement
(Right handle backward and Left handle forward movements).
10 right handed healthy people (7 Males, 3 Females, 29.9 ± 6.21
years old) participated in this study. As it was expected,
differences between rest and bimanual activity conditions (L2R
and R2L) were found, surprisingly, on lowest frequency bands,
Delta and Theta. More relevant results were found on Delta
band at the right Hemisphere and inter-hemispherical relations,
specifically for intra-hemispherical connectivity for CPSD
relations with p=0.005 (L2R) and p=0.02 (R2L), and power
quantified with PSD with p=0.023 (L2R) and p=0.03 (R2L),
while inter-hemispherical connectivity got lower values on
resting compared to L2R movement with a p=0.015. Besides,
comparisons between resting and movement in Theta band
showed significant results for inter-hemispherical connectivity
(p=0.03, L2R vs Rest, and R2L vs Rest) and differences in power
for Left Hemisphere (p=0.05). Finally, non-significant
differences were found in motor cortex between the two kind of
bimanual activities tested on this work. These results create an
opening scenario to test for mirror effect of bimanual activities
from one hemisphere to another on populations with hemi
paretic conditions, aiming to apply it in a near future as therapy
for Stroke Survivors.info:eu-repo/semantics/publishedVersio
Functionalised Poly(Vinyl Alcohol)/Graphene Oxide as Polymer Composite Electrolyte Membranes
[EN] Crosslinked poly(vinyl alcohol) (PVA) based composite films were prepared as polyelectrolyte membranes for low temperature direct ethanol fuel cells (DEFC). The membranes were functionalised by means of the addition of graphene oxide (GO) and sulfonated graphene oxide (SGO) and crosslinked with sulfosuccinic acid (SSA). The chemical structure was corroborated and suitable thermal properties were found. Although the addition of GO and SGO slightly decreased the proton conductivity of the membranes, a significant reduction of the ethanol solution swelling and crossover was encountered, more relevant for those functionalised with SGO. In general, the composite membranes were stable under simulated service conditions. The addition of GO and SGO particles permitted to buffer the loss and almost retain similar proton conductivity than prior to immersion. These membranes are alternative polyelectrolytes, which overcome current concerns of actual commercial membranes such as the high cost or the crossover phenomenon.The authors would like to thank the support of the European Union through the European Regional Development Funds (ERDF). The Spanish Ministry of Economy, Industry and Competitiveness, is thanked for the research project POLYDECARBOCELL (ENE2017-86711-C3-1-R). The Spanish Ministry of Education, Culture and Sports is thanked for the FPU grant for O. Gil-Castell (FPU13/01916).Gil Castell, Ó.; Cerveró, R.; Teruel Juanes, R.; Badia, JD.; Ribes Greus, MD. (2019). Functionalised Poly(Vinyl Alcohol)/Graphene Oxide as Polymer Composite Electrolyte Membranes. Journal of Renewable Materials. 7(7):655-665. https://doi.org/10.32604/jrm.2019.04401S6556657
Hyperplasia of alveolar neuroendocrine cells in rat lung carcinogenesis by silica with selective expression of proadrenomedullin-derived peptides and amidating enzymes
Pulmonary neuroendocrine (NE) cells are found as clusters called neuroepithelial bodies (NEBs) or as single cells scattered in the respiratory epithelium. They express a variety of bioactive peptides, and they are thought to be the origin of NE lung tumors. Proadrenomedullin N-terminal 20 peptide (PAMP) is a peptide derived from the same precursor as adrenomedullin (AM). AM and PAMP are C-terminally amidated during their processing by a well-characterized amidating enzyme, peptidylglycine alpha-amidating monooxygenase (PAM). We explored AM, PAMP, and PAM expression as markers for NE hyperplasia in three rodent species (Fischer 344 rats, Syrian golden hamsters, and A/J mice) after a single intratracheal instillation of crystalline silica (quartz), which was previously found to induce different reactions in the three species. Rats developed a marked silicosis, with alveolar and bronchiolar hyperplasia and formation of peripheral lung epithelial tumors. Mice developed a moderate degree of silicosis, but not epithelial hyperplasia or tumors. Hamsters showed dust-storage lesions, but not silicosis or tumors. NE cells were immunolabeled for calcitonin gene-related peptide (CGRP), AM, PAMP, and PAM in serial sections of each lung. The numbers of positive NEBs per lung area and positive cells per NEB were quantified. A marked hyperplastic reaction in the NEBs of silica treated rats occurred only in alveolar NEBs, but not in bronchiolar NEBs. From Month 11 onwards, there were marked differences in the number of alveolar NEBs per section and in the number of cells per alveolar NEB immunoreactive for CGRP. No hyperplastic NE cell reaction was observed in silica-treated mice and hamsters. Significant PAMP and PAM expression was seen only in rat hyperplastic alveolar and in bronchiolar NEBs from Month 11 onwards. In E18, rat fetal lung NEBs were found to be strongly positive for PAMP and PAM
Finding the optimal time window for increased classification accuracy during motor imagery
Motor imagery classification using electroencephalography is based on feature extraction over a length of
time, and different configurations of settings can alter the performance of a classifier. Nevertheless, there
is a lack of standardized settings for motor imagery classification. This work analyzes the effect of age on
motor imagery training performance for two common spatial pattern-based classifier pipelines and various
configurations of timing parameters, such as epochs, windows, and offsets. Results showed significant (p
≤ 0.01) inverse correlations between performance and feature quantity, as well as between performance and
epoch/window ratio.info:eu-repo/semantics/publishedVersio
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