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1.
Sensors (Basel) ; 22(22)2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36433386

RESUMO

Throughout the years, wildfires have negatively impacted ecological systems and urban areas. Hence, reinforcing territorial risk management strategies against wildfires is essential. In this study, we built an early alert system (EAS) with two different Machine Learning (ML) techniques to calculate the meteorological conditions of two Colombian areas: (i) A 3D convolutional neural net capable of learning from satellite data and (ii) a convolutional network to bias-correct the Weather Research and Forecasting (WRF) model output. The results were used to quantify the daily Fire Weather Index and were coupled with the outcomes from a land cover analysis conducted through a Naïve-Bayes classifier to estimate the probability of wildfire occurrence. These results, combined with an assessment of global vulnerability in both locations, allow the construction of daily risk maps in both areas. On the other hand, a set of short-term preventive and corrective measures were suggested to public authorities to implement, after an early alert prediction of a possible future wildfire. Finally, Soil Management Practices are proposed to tackle the medium- and long-term causes of wildfire development, with the aim of reducing vulnerability and promoting soil protection. In conclusion, this paper creates an EAS for wildfires, based on novel ML techniques and risk maps.


Assuntos
Incêndios , Incêndios Florestais , Teorema de Bayes , Tempo (Meteorologia) , Solo
2.
Molecules ; 27(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35745010

RESUMO

The development of green technologies and bioprocesses such as solid-state fermentation (SSF) is important for the processing of macroalgae biomass and to reduce the negative effect of Sargassum spp. on marine ecosystems, as well as the production of compounds with high added value such as fungal proteins. In the present study, Sargassum spp. biomass was subjected to hydrothermal pretreatments at different operating temperatures (150, 170, and 190 °C) and pressures (3.75, 6.91, and 11.54 bar) for 50 min, obtaining a glucan-rich substrate (17.99, 23.86, and 25.38 g/100 g d.w., respectively). The results indicate that Sargassum pretreated at a pretreatment temperature of 170 °C was suitable for fungal growth. SSF was performed in packed-bed bioreactors, obtaining the highest protein content at 96 h (6.6%) and the lowest content at 72 h (4.6%). In contrast, it was observed that the production of fungal proteins is related to the concentration of sugars. Furthermore, fermentation results in a reduction in antinutritional elements, such as heavy metals (As, Cd, Pb, Hg, and Sn), and there is a decrease in ash content during fermentation kinetics. Finally, this work shows that Aspergillus oryzae can assimilate nutrients found in the pretreated Sargassum spp. to produce fungal proteins as a strategy for the food industry.


Assuntos
Sargassum , Biomassa , Reatores Biológicos/microbiologia , Ecossistema , Fermentação , Proteínas Fúngicas
3.
Sci Rep ; 12(1): 10597, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35732879

RESUMO

The increasing human population demands an increase in crop yields that must be implemented through breeding programmes to ensure a more efficient and sustainable production of agro-food products. In the framework of breeding, genetic crosses are developed between cultivated species such as wheat and their relative species that are used as genetic donors to transfer desirable agronomic traits into the crop. Unfortunately, interspecific associations between chromosomes from the donor species and the cultivar are rare during meiosis, the process to produce gametes in organisms with sexual reproduction, hampering the transfer of genetic variability into wheat. In addition, little is known about how homologous (equivalent) chromosomes initiate interaction and recognition within the cell nucleus to enter meiosis. In this context, we aim to get insight into wheat chromatin structure, particularly the distribution of homologous chromosomes within the cell nucleus and their putative interactions in premeiotic stages to facilitate chromosome associations and recombination at the beginning of meiosis. Cytogenetics allows the study of both the structure and the behaviour of chromosomes during meiosis and is key in plant breeding. In this study we visualized an extra pair of barley homologous chromosomes in a wheat genetic background to study the spatial distribution, arrangements and interactions occurring exclusively between this pair of homologous chromosomes during premeiosis using fluorescence in situ hybridization (FISH). Our results suggest that homologous chromosomes can initiate interactions in premeiotic stages that could facilitate the processes of specific chromosome recognition and association occurring at the onset of meiosis.


Assuntos
Melhoramento Vegetal , Triticum , Pareamento Cromossômico/genética , Cromossomos , Hibridização in Situ Fluorescente , Meiose/genética , Triticum/genética
4.
Animals (Basel) ; 12(9)2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35565483

RESUMO

Today, governments and administrations strive to minimise issues associated with Feral Pigeon (Columba livia var. domestica) colonies in urban areas. Scientific evidence has demonstrated that control measures are ineffective in the long term, and colonies recover rapidly. Most scientific research has occurred under high-density circumstances, primarily in large city centres. Moreover, very few studies have been conducted in residential zones or suburban areas where colony densities are lower, but where Feral Pigeons generate the same issues. In this study, we analysed the recovery time of Feral Pigeon colonies in 11 buildings in low-density urban areas where control campaigns were previously conducted to reduce their abundance. Recovery times were highly variable among the buildings (50−3072 days). Distance to the nearest uncontrolled colony of Feral Pigeons, i.e., a source area, was the primary factor that contributed to recovery time, which significantly increased with increasing distance to source colonies. Thus, buildings closest to the Pigeons' source areas (<500 m) were recolonised more rapidly than were buildings that were >500 m away from source areas. Our findings highlight the relevance of identifying an effective management unit for the implementation of control programmes to reduce immigration rates and increase long-term effects.

5.
Protein Sci ; 30(12): 2408-2417, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34719069

RESUMO

The interactions of proteins with surfaces are important in both biological processes and biotechnologies. In contrast to decades of study regarding the biophysics of proteins in bulk solution, however, our mechanistic understanding of the biophysics of proteins interacting with surfaces remains largely qualitative. In response, we have set to explore quantitatively the thermodynamics of protein-surface interactions. In this work, we explore systematically the role of electrostatics in modulating the interaction between proteins and charged surfaces. In particular, we use electrochemistry to explore the extent to which a macroscopic, hydroxyl-coated surface held at a slightly negative potential affects the folding thermodynamics of surface-attached protein variants with different composition of charged amino acids. Doing so, we find that attachment to the surface generally leads to a net stabilization, presumably due to excluded volume effects that reduce the entropy of the unfolded state. The magnitude of this stabilization, however, is strongly correlated with the charged-residue content of the protein. In particular, we find statistically significant correlations with both the net charge of the protein, with greater negative charge leading to less stabilization by the surface, and with the number of arginines, with more arginines leading to greater stabilization. Such findings refine our understanding of protein-surface interactions, providing in turn a guiding rationale to achieve the functional deposition of proteins on artificial surfaces for implementation in, for example, protein-based biotechnologies.


Assuntos
Aminoácidos/química , Dobramento de Proteína , Proteínas/química , Motivos de Aminoácidos , Técnicas Eletroquímicas , Cinética , Ligação Proteica , Desnaturação Proteica , Eletricidade Estática , Propriedades de Superfície , Termodinâmica
6.
Front Plant Sci ; 12: 672489, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149773

RESUMO

Genomic architecture facilitates chromosome recognition, pairing, and recombination. Telomeres and subtelomeres play an important role at the beginning of meiosis in specific chromosome recognition and pairing, which are critical processes that allow chromosome recombination between homologs (equivalent chromosomes in the same genome) in later stages. In plant polyploids, these terminal regions are even more important in terms of homologous chromosome recognition, due to the presence of homoeologs (equivalent chromosomes from related genomes). Although telomeres interaction seems to assist homologous pairing and consequently, the progression of meiosis, other chromosome regions, such as subtelomeres, need to be considered, because the DNA sequence of telomeres is not chromosome-specific. In addition, recombination operates at subtelomeres and, as it happens in rye and wheat, homologous recognition and pairing is more often correlated with recombining regions than with crossover-poor regions. In a plant breeding context, the knowledge of how homologous chromosomes initiate pairing at the beginning of meiosis can contribute to chromosome manipulation in hybrids or interspecific genetic crosses. Thus, recombination in interspecific chromosome associations could be promoted with the aim of transferring desirable agronomic traits from related genetic donor species into crops. In this review, we summarize the importance of telomeres and subtelomeres on chromatin dynamics during early meiosis stages and their implications in recombination in a plant breeding framework.

7.
Proc Natl Acad Sci U S A ; 118(17)2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33888580

RESUMO

The North American tiger salamander species complex, including its best-known species, the Mexican axolotl, has long been a source of biological fascination. The complex exhibits a wide range of variation in developmental life history strategies, including populations and individuals that undergo metamorphosis; those able to forego metamorphosis and retain a larval, aquatic lifestyle (i.e., paedomorphosis); and those that do both. The evolution of a paedomorphic life history state is thought to lead to increased population genetic differentiation and ultimately reproductive isolation and speciation, but the degree to which it has shaped population- and species-level divergence is poorly understood. Using a large multilocus dataset from hundreds of samples across North America, we identified genetic clusters across the geographic range of the tiger salamander complex. These clusters often contain a mixture of paedomorphic and metamorphic taxa, indicating that geographic isolation has played a larger role in lineage divergence than paedomorphosis in this system. This conclusion is bolstered by geography-informed analyses indicating no effect of life history strategy on population genetic differentiation and by model-based population genetic analyses demonstrating gene flow between adjacent metamorphic and paedomorphic populations. This fine-scale genetic perspective on life history variation establishes a framework for understanding how plasticity, local adaptation, and gene flow contribute to lineage divergence. Many members of the tiger salamander complex are endangered, and the Mexican axolotl is an important model system in regenerative and biomedical research. Our results chart a course for more informed use of these taxa in experimental, ecological, and conservation research.


Assuntos
Ambystoma/genética , Ambystoma/metabolismo , Ambystoma mexicanum/genética , Animais , Bases de Dados Genéticas , Fluxo Gênico , Genética Populacional/métodos , Geografia , Larva/genética , Metamorfose Biológica/genética , América do Norte , Filogenia
8.
Plant Genome ; 13(3): e20065, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33029942

RESUMO

Bread wheat, Triticum aestivum L., is one of the most important crops in the world. Understanding its genome organization (allohexaploid; AABBDD; 2n = 6x = 42) is essential for geneticists and plant breeders. Particularly, the knowledge of how homologous chromosomes (equivalent chromosomes from the same genome) specifically recognize each other to pair at the beginning of meiosis, the cellular process to generate gametes in sexually reproducing organisms, is fundamental for plant breeding and has a big influence on the fertility of wheat plants. Initial homologous chromosome interactions contribute to specific recognition and pairing between homologues at the onset of meiosis. Understanding the molecular basis of these critical processes can help to develop genetic tools in a breeding context to promote interspecific chromosome associations in hybrids or interspecific genetic crosses to facilitate the transfer of desirable agronomic traits from related species into a crop like wheat. The terminal regions of chromosomes, which include telomeres and subtelomeres, participate in chromosome recognition and pairing. We present a detailed molecular analysis of subtelomeres of wheat chromosome arms 1AS, 4AS, 7AS, 7BS and 7DS. Results showed a high polymorphism in the subtelomeric region among homoeologues (equivalent chromosomes from related genomes) for all the features analyzed, including genes, transposable elements, repeats, GC content, predicted CpG islands, recombination hotspots and targeted sequence motifs for relevant DNA-binding proteins. These polymorphisms might be the molecular basis for the specificity of homologous recognition and pairing in initial chromosome interactions at the beginning of meiosis in wheat.


Assuntos
Cromossomos de Plantas , Triticum , Cruzamento , Meiose/genética , Análise de Sequência , Triticum/genética
9.
Cells ; 9(5)2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32438605

RESUMO

Reelin is an extracellular glycoprotein that modulates neuronal function and synaptic plasticity in the adult brain. Decreased levels of Reelin activity have been postulated as a key factor during neurodegeneration in Alzheimer´s disease (AD) and in aging. Thus, changes in levels of full-length Reelin and Reelin fragments have been revealed in cerebrospinal fluid (CSF) and in post-mortem brains samples of AD patients with respect to non-AD patients. However, conflicting studies have reported decreased or unchanged levels of full-length Reelin in AD patients compared to control (nND) cases in post-mortem brains and CSF samples. In addition, a compelling analysis of Reelin levels in neurodegenerative diseases other than AD is missing. In this study, we analyzed brain levels of RELN mRNA and Reelin protein in post-mortem frontal cortex samples from different sporadic AD stages, Parkinson's disease with dementia (PDD), and Creutzfeldt-Jakob disease (sCJD), obtained from five different Biobanks. In addition, we measured Reelin protein levels in CSF samples of patients with mild cognitive impairment (MCI), dementia, or sCJD diagnosis and a group of neurologically healthy cases. The results indicate an increase in RELN mRNA in the frontal cortex of advanced stages of AD and in sCJD(I) compared to controls. This was not observed in PDD and early AD stages. However, Reelin protein levels in frontal cortex samples were unchanged between nND and advanced AD stages and PDD. Nevertheless, they decreased in the CSF of patients with dementia in comparison to those not suffering with dementia and patients with MCI. With respect to sCJD, there was a tendency to increase in brain samples in comparison to nND and to decrease in the CSF with respect to nND. In conclusion, Reelin levels in CSF cannot be considered as a diagnostic biomarker for AD or PDD. However, we feel that the CSF Reelin changes observed between MCI, patients with dementia, and sCJD might be helpful in generating a biomarker signature in prodromal studies of unidentified dementia and sCJD.


Assuntos
Moléculas de Adesão Celular Neuronais/genética , Proteínas da Matriz Extracelular/genética , Proteínas do Tecido Nervoso/genética , Doenças Neurodegenerativas/genética , Serina Endopeptidases/genética , Encéfalo/metabolismo , Encéfalo/patologia , Moléculas de Adesão Celular Neuronais/líquido cefalorraquidiano , Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas da Matriz Extracelular/líquido cefalorraquidiano , Proteínas da Matriz Extracelular/metabolismo , Humanos , Proteínas do Tecido Nervoso/líquido cefalorraquidiano , Proteínas do Tecido Nervoso/metabolismo , Doenças Neurodegenerativas/líquido cefalorraquidiano , Doenças Neurodegenerativas/patologia , Mudanças Depois da Morte , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína Reelina , Serina Endopeptidases/líquido cefalorraquidiano , Serina Endopeptidases/metabolismo
10.
Astron J ; 159(3)2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32095021

RESUMO

We present a survey of variable stars detected in K2 Campaign 13 within the massive intermediate-age (~1 Gyr) open cluster NGC 1817. We identify a complete sample of 44 red clump stars in the cluster, and have measured asteroseismic quantities (ν max and/or Δν) for 29 of them. Five stars showed suppressed dipole modes, and the occurrence rates indicate that mode suppression is unaffected by evolution through core helium burning. A subset of the giants in NGC 1817 (and in the similarly aged cluster NGC 6811) have ν max and Δν values at or near the maximum observed for core helium-burning stars, indicating they have core masses near the minimum for fully nondegenerate helium ignition. Further asteroseismic study of these stars can constrain the minimum helium core mass in red clump stars and the physics that determines this limit. Two giant stars show photometric variations on timescales similar to previously measured spectroscopic orbits. Thirteen systems in the field show eclipses, but only five are probable cluster members. We identify 32 δ Sct pulsators, 27 γ Dor candidates, and 7 hybrids that are probable cluster members, with most being new detections. We used the ensemble properties of the δ Sct stars to identify stars with possible radial pulsation modes. Among the oddities we have uncovered are: an eccentric orbit for a short-period binary containing a δ Sct pulsating star; a rare subgiant within the Hertzsprung gap showing δ Sct pulsations; and two hot γ Dor pulsating star candidates.

11.
Sci Rep ; 10(1): 2726, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066846

RESUMO

Meiosis is a specialized type of cell division occurring in sexually reproducing organisms to generate haploid cells known as gametes. In flowering plants, male gametes are produced in anthers, being encased in pollen grains. Understanding the genetic regulation of meiosis key events such as chromosome recognition and pairing, synapsis and recombination, is needed to manipulate chromosome associations for breeding purposes, particularly in important cereal crops like wheat. Reverse transcription-quantitative PCR (RT-qPCR) is widely used to analyse gene expression and to validate the results obtained by other transcriptomic analyses, like RNA-seq. Selection and validation of appropriate reference genes for RT-qPCR normalization is essential to obtain reproducible and accurate expression data. In this work, twelve candidate reference genes were evaluated using the mainstream algorithms geNorm, Normfinder, BestKeeper and ΔCt, then ranked from most to least suitable for normalization with RefFinder. Different sets of reference genes were recommended to normalize gene expression data in anther meiosis of bread and durum wheat, their corresponding genotypes in the absence of the Ph1 locus and for comparative studies among wheat genotypes. Comparisons between meiotic (anthers) and somatic (leaves and roots) wheat tissues were also carried out. To the best of our knowledge, our study provides the first comprehensive list of reference genes for robust RT-qPCR normalization to study differentially expressed genes during male meiosis in wheat in a breeding framework.


Assuntos
Regulação da Expressão Gênica de Plantas , Genes Essenciais , Meiose , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Transcriptoma , Triticum/genética , Algoritmos , Produtos Agrícolas , Flores/genética , Flores/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Melhoramento Vegetal , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Padrões de Referência , Triticum/crescimento & desenvolvimento
12.
Philos Trans A Math Phys Eng Sci ; 376(2118)2018 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-29555799

RESUMO

As was recently shown by the authors, quantum probability theory can be used for the modelling of the process of decision-making (e.g. probabilistic risk analysis) for macroscopic geophysical structures such as hydrocarbon reservoirs. This approach can be considered as a geophysical realization of Hilbert's programme on axiomatization of statistical models in physics (the famous sixth Hilbert problem). In this conceptual paper, we continue development of this approach to decision-making under uncertainty which is generated by complexity, variability, heterogeneity, anisotropy, as well as the restrictions to accessibility of subsurface structures. The belief state of a geological expert about the potential of exploring a hydrocarbon reservoir is continuously updated by outputs of measurements, and selection of mathematical models and scales of numerical simulation. These outputs can be treated as signals from the information environment E The dynamics of the belief state can be modelled with the aid of the theory of open quantum systems: a quantum state (representing uncertainty in beliefs) is dynamically modified through coupling with E; stabilization to a steady state determines a decision strategy. In this paper, the process of decision-making about hydrocarbon reservoirs (e.g. 'explore or not?'; 'open new well or not?'; 'contaminated by water or not?'; 'double or triple porosity medium?') is modelled by using the Gorini-Kossakowski-Sudarshan-Lindblad equation. In our model, this equation describes the evolution of experts' predictions about a geophysical structure. We proceed with the information approach to quantum theory and the subjective interpretation of quantum probabilities (due to quantum Bayesianism).This article is part of the theme issue 'Hilbert's sixth problem'.

14.
Int J Mol Sci ; 19(2)2018 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-29373484

RESUMO

More than 140 million people live and works (in a chronic or intermittent form) above 2500 m worldwide and 35 million live in the Andean Mountains. Furthermore, in Chile, it is estimated that 55,000 persons work in high altitude shifts, where stays at lowlands and interspersed with working stays at highlands. Acute exposure to high altitude has been shown to induce oxidative stress in healthy human lowlanders, due to an increase in free radical formation and a decrease in antioxidant capacity. However, in animal models, intermittent hypoxia (IH) induce preconditioning, like responses and cardioprotection. Here, we aimed to describe in a rat model the responses on cardiac and vascular function to 4 cycles of intermittent hypobaric hypoxia (IHH). Twelve adult Wistar rats were randomly divided into two equal groups, a four-cycle of IHH, and a normobaric hypoxic control. Intermittent hypoxia was induced in a hypobaric chamber in four continuous cycles (1 cycle = 4 days hypoxia + 4 days normoxia), reaching a barometric pressure equivalent to 4600 m of altitude (428 Torr). At the end of the first and fourth cycle, cardiac structural, and functional variables were determined by echocardiography. Thereafter, ex vivo vascular function and biomechanical properties were determined in femoral arteries by wire myography. We further measured cardiac oxidative stress biomarkers (4-Hydroxy-nonenal, HNE; nytrotirosine, NT), reactive oxygen species (ROS) sources (NADPH and mitochondrial), and antioxidant enzymes activity (catalase, CAT; glutathione peroxidase, GPx, and superoxide dismutase, SOD). Our results show a higher ejection and shortening fraction of the left ventricle function by the end of the 4th cycle. Further, femoral vessels showed an improvement of vasodilator capacity and diminished stiffening. Cardiac tissue presented a higher expression of antioxidant enzymes and mitochondrial ROS formation in IHH, as compared with normobaric hypoxic controls. IHH exposure determines a preconditioning effect on the heart and femoral artery, both at structural and functional levels, associated with the induction of antioxidant defence mechanisms. However, mitochondrial ROS generation was increased in cardiac tissue. These findings suggest that initial states of IHH are beneficial for cardiovascular function and protection.


Assuntos
Hipóxia/fisiopatologia , Estresse Oxidativo , Vasodilatação , Função Ventricular Esquerda , Adaptação Fisiológica , Animais , Hipóxia/metabolismo , Masculino , Mitocôndrias Musculares/metabolismo , Miocárdio/metabolismo , Ratos , Ratos Wistar
15.
Materials (Basel) ; 10(12)2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29189745

RESUMO

In recent years there has been an increasing tendency to recycle the wastes generated by building companies in the construction industry, demolition wastes being the most important in terms of volume. The aim of this work is to study the possibility of using recycled aggregates from construction and demolition wastes in the preparation of precast non-structural concretes. To that purpose, two different percentages (15% and 30%) of natural aggregates were substituted by recycled aggregates in the manufacture of paving blocks and hollow tiles. Dosages used by the company have not been changed by the introduction of recycled aggregate. Precast elements have been tested by means of compressive and flexural strength, water absorption, density, abrasion, and slipping resistance. The results obtained show the possibility of using these wastes at an industrial scale, satisfying the requirements of the Spanish standards for these elements.

16.
Philos Trans A Math Phys Eng Sci ; 375(2106)2017 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-28971950

RESUMO

The paper starts with a brief review of the literature about uncertainty in geological, geophysical and petrophysical data. In particular, we present the viewpoints of experts in geophysics on the application of Bayesian inference and subjective probability. Then we present arguments that the use of classical probability theory (CP) does not match completely the structure of geophysical data. We emphasize that such data are characterized by contextuality and non-Kolmogorovness (the impossibility to use the CP model), incompleteness as well as incompatibility of some geophysical measurements. These characteristics of geophysical data are similar to the characteristics of quantum physical data. Notwithstanding all this, contextuality can be seen as a major deviation of quantum theory from classical physics. In particular, the contextual probability viewpoint is the essence of the Växjö interpretation of quantum mechanics. We propose to use quantum probability (QP) for decision-making during the characterization, modelling, exploring and management of the intelligent hydrocarbon reservoir Quantum Bayesianism (QBism), one of the recently developed information interpretations of quantum theory, can be used as the interpretational basis for such QP decision-making in geology, geophysics and petroleum projects design and management.This article is part of the themed issue 'Second quantum revolution: foundational questions'.

17.
J Sci Food Agric ; 97(14): 4827-4834, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28382717

RESUMO

BACKGROUND: There are many substances that can interfere with olive oil quality. Some of them are well characterized, but many others have an unknown origin. Saturated hydrocarbons make an extraordinary complex family of numerous molecules, some of them present naturally in vegetable oils. When major natural saturated hydrocarbons are analyzed by standard chromatographic methods, this complex mixture of saturated hydrocarbons appears as a hump in the chromatogram and is commonly named as unresolved complex mixture (UCM), whose origin remains unknown. RESULTS: In this work we studied the occurrence and the origin of aliphatic saturated hydrocarbons in olive oil. Hydrocarbons were analyzed in olive oil and along the industrial process of oil extraction. We also analyzed n-alkanes and the UCM fraction of hydrocarbons in leaf, fruit and oil from different varieties and different locations, and we also analyzed the soils at these locations. CONCLUSIONS: We conclude that the hydrocarbons present in olive oil do not necessarily have their origin in a contamination during olive oil elaboration; they seem to have a natural origin, as a result of olive tree metabolism and/or as the result of an intake and accumulation by the olive tree directly from the environment during its entire life cycle. © 2017 Society of Chemical Industry.


Assuntos
Contaminação de Alimentos/análise , Frutas/química , Hidrocarbonetos/análise , Olea/química , Azeite de Oliva/análise , Alcanos/análise , Folhas de Planta/química , Poluentes do Solo/análise
18.
Food Sci Biotechnol ; 26(4): 993-1001, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30263629

RESUMO

Pretreatments with different concentrations of sulfuric acid (0, 0.5, and 1% v/v) and temperatures (28 and 121 °C at 103 kPa in an autoclave) were performed on banana peels (BP) milled by mechanical grinding and grinding in a blender as well as without grinding. Cellulose, hemicellulose, lignin, ash, and total and reducing sugar contents were evaluated. The highest yields of cellulose enzymatic hydrolysis (99%) were achieved with liquefied autoclaved BP treated with 0.5 and 1% acid after 48 h of hydrolysis. Ethanol production by Kluyveromyces marxianus fermentation was assayed using hydrolyzed BP at 10, 15, and 20% (w/w). The highest ethanol level (21 g/L) was reached after 24 h of fermentation with 20% (w/w) BP. Kinetics of the consumption of reducing sugars under this fermentation condition demonstrates the presence of a lag period (about 8 h). Thus, BP are a good source for ethanol production.

19.
Front Psychol ; 8: 2259, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29354084

RESUMO

The triad is a particular structure in which an ambivalent social relationship takes place. This work is focused on the search of behavioral regularities in the practice of motor games in triad, which is a little known field. For the detection of behavioral patterns not visible to the naked eye, we use Theme. A chasing games model was followed, with rules, and in two different structures (A↔B↔C↔A and A → B → C → A) on four class groups (two for each structure), for a total of 84, 12, and 13 year old secondary school students, 37 girls (44%) and 47 boys (56%). The aim was to examine if the players' behavior, in relation to the triad structure, matches with any ludic behavior patterns. An observational methodology was applied, with a nomothetic, punctual and multidimensional design. The intra and inter-evaluative correlation coefficients and the generalizability theory ensured the quality of the data. A mixed behavioral role system was used (four criteria and 15 categories), and the pattern detection software Theme was applied to detect temporal regularities in the order of event occurrences. The results show that time location of motor responses in triad games was not random. In the "maze" game we detected more complex ludic patterns than the "three fields" game, which might be explained by means of structural determinants such as circulation. This research points out the decisional complexity in motor games, and it confirms the differences among triads from the point of view of motor communication.

20.
Prep Biochem Biotechnol ; 47(6): 554-561, 2017 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-28032818

RESUMO

In the present study, the interactions between chitosan-coated magnetic nanoparticles (C-MNP) and Trichoderma sp. spores as well as Kluyveromyces marxianus cells were studied. By Plackett-Burman design, it was demonstrated that factors which directly influenced on yeast cell immobilization and magnetic separation were inoculum and C-MNP quantity, stirring speed, interaction time, and volume of medium, while in the case of fungal spores, the temperature also was disclosed as an influencing factor. Langmuir and Freundlich models were applied for the mathematical analysis of adsorption isotherms at 30°C. For Trichoderma sp. spore adsorption isotherm, the highest correlation coefficient was observed for lineal function of Langmuir model with a maximum adsorption capacity at 5.00E + 09 spores (C-MNP g-1). Adsorption isotherm of K. marxianus cells was better adjusted to Freundlich model with a constant (Kf) estimated as 2.05E + 08 cells (C-MNP g-1). Both systems may have a novel application in fermentation processes assisted with magnetic separation of biomass.


Assuntos
Quitosana/química , Kluyveromyces/citologia , Nanopartículas de Magnetita/química , Esporos Fúngicos/isolamento & purificação , Trichoderma/citologia , Adsorção , Separação Celular
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