Co-(V,Nb)–Sn Heusler alloys are studied within the GGA-PBE and hybrid (HSE06) approaches. From HSE06 calculations, the Half-Heusler structures CoVSn and CoNbSn are semiconductors with bandgaps of ...1.33eV and 1.50eV, respectively. On the other hand, the Full-Heusler systems Co2VSn and Co2NbSn have a half-metallic nature and bandgaps of 1.26eV and 0.86eV, respectively. From the analysis of the band structure, high values were found for the effective masses of the structures studied. Furthermore, the results of magnetic moments and chemical bonds are presented, indicating the presence of covalent-polar bonds. Finally, thermoelectric parameters such as Seebeck coefficient (S), electronic conductivity (σ), thermal conductivity (κ), and Figure of Merit (ZT) were determined, including vibrational effects (phonons), thus improving the results that showed good agreement with experimental data. By determining these properties, it is possible to indicate strategies to improve the thermoelectric performance of these materials.
Studies on drying of fruits and vegetables by means of different methods are numerous. This review aims at presenting the most usual quality analyses carried out in dried fruits and vegetables over ...the last five years along with the most used drying methods. It was prepared based on a search on Scopus database with the term ‘drying fruit vegetables’. Results show that color and microstructure can be preserved, apparent density can be reduced, and high rehydration capacity can be achieved by using mild drying methods like freeze-drying and innovative drying methods like conductive multi-flash drying. Shrinkage and water activity can be minimized by using pretreatments like osmotic dehydration, ultrasound, and pulsed electric fields. Such pretreatments also produce crispy texture, which can also be obtained with the use of hot air drying followed by microwave-vacuum drying. Antioxidant activity, phenolic compounds and vitamin C content can be maximized by using innovative pretreatments like immersion in solutions rich in bioactive compounds and short drying time. Microbial counts can be decreased by using pretreatments like immersion in ethanol, and modified atmosphere packaging. High sensory acceptability can also be achieved by using innovative drying methods, like instant controlled pressure drop drying.
The presented work is focused on the creation and validation of original tools for the detection of apple fruits with false indication of geographical origin by analysing the mineral composition and ...isotope ratios using the method (ICP-MS) mass spectrometry with inductively coupled plasma. The obtained profiles of the element composition (P, K, Mg, Fe, Cu a Zn) and isotope ratios (86Sr/87Sr a 10B/11B) of individual samples were statistically processed using principal component analysis (PCA). The achieved results of the analysis of the mineral composition and isotope ratios of Polish and Czech apples show different trends, especially for the elements P, Cu and for the isotope ratio of 10B/11B. However, these trends alone do not yet allow for a sufficient distinction among the geographical origin of apples. These trends were not statistically detected for other analysed elements and for the isotope ratio 86Sr/87Sr. Therefore, in the future we plan to perform a combined multidimensional analysis with other methods, such as the evaluation of selected phenolic metabolites in the fruit flesh.
The purpose of the research was to carry out some analyses in order to establish the physico-chemical composition and the fungal load of the plant substrates used for raising animals, in a cattle ...farm in the Moldova area in 2022. There were five categories of samples (75 determinations in total) - alfalfa hay, corn silage, mixed feed ration, concentrates, corn grains and were analysed randomly from the farm. The results of the physico-chemical composition of the feed by the FT-NIRS technique were in accordance with the regulations in force and no significant differences were found between the samples, it is certain that the humidity had a higher percentage, hence the fact that there were developed species of fungi speaking from the point of view of mycotic contamination. The highest fungal load was recorded in corn grains and corn silage, and the lowest value was recorded in alfalfa hay. The number of colony-forming units per gram of sample was determined by the serial dilution technique in a double agar layer. The results obtained during the analysed period highlighted the presence of the genus Penicillium to the greatest extent (28%), and the lowest percentage was recorded for the genus Cladosporium (5.3%).
The Brazilian mojarra, Eugerres brasilianus, is an economically important species for the artisanal fisheries usually found in the estuarine waters along the southwest Atlantic Ocean. Despite this, ...knowledge about its population structure is scarce, and no management strategies have been applied to ensure the fisheries sustainability in Brazil. Thus, the present study intended to understand the population dynamics of E. brasilianus in three costal lagoons located in Rio de Janeiro, Brasil. A total of 90 individuals were collected in the lagoon systems of Itaipu, Saquarema and Araruama, between December 2019 and March 2020. A pre-selection of 30 individuals per location from the same age group (2 years old), following age estimation by counting the annual growth increments, were used. The contour of the sagittal otoliths was evaluated using elliptical Fourier descriptors (EFD), and the multi-elemental signatures (MES) of the whole otoliths were obtained using solution-based inductively coupled plasma mass spectrometry. Data were analyzed using univariate and multivariate statistics to assess the degree of separation between individuals from different lagoons. EFD revealed significant differences among individuals from the different sampling regions. MES exhibited distinct regional patterns, mainly driven by differences in Cu/Ca, Li/Ca, Mg/Ca, Mn/Ca, and Sr/Ca ratios. Reclassification accuracy rates obtained from linear discriminant function analyses using both EFD and MES of otoliths were 100% (Itaipu), 97% (Araruama) and 90% (Saquarema). Therefore, a clear distinction was observed among these groups, which was related to the inherent characteristics of each lagoon system, their semi-restricted connectivity with the adjacent coastal zone, as well as the estuarine-opportunistic behavior of the species. Thus, the results suggest that these fisheries should be managed as different subpopulation-units. However, more studies should be carried out about the fish movements and life history events of this species in southeastern Brazil.
•Population structure of Eugerres brasilianus in coastal lagoons of Rio de Janeiro, Brazil, was studied using otoliths.•The otoliths revealed the existence of distinct subpopulations resulting from the characteristics of each lagoon system.•These fish groups should be regarded as different fisheries management-units.
Morphological, morphometric, and chemical analysis of otoliths have proven to be useful tools for intraspecific comparison and identification of fish stocks. In the present study, we used otolith ...silhouette and morphometric analysis (n = 103) in addition to chemical signatures (n = 20) to test the hypothesis of a single stock unit of skipjack tuna (Katsuwonus pelamis) in the Southwest Atlantic Ocean (20–34°S). No significant differences were found between sexes (t-test p > 0.05), enabling analyses for all study specimens to be grouped. Cluster analysis using Fourier coefficients (30 first harmonics) differentiated three otolith morphotypes within South (28–34°S) and Southeast (20–28°S) regions of the study area. Harmonic principal component analysis using the first two significant axes showed no pattern of spatial separation by region. Among the seven shape descriptors examined, only circularity and form factor showed significant differences between the morphotypes (A and B). Microchemistry analysis (LA/ICP-MS) applied to the core portion of fish otoliths showed significant differences in Ba, Mn and Mg concentrations between the two regions and morphotypes (p < 0.05). These results support that the Katsuwonus pelamis population in the Southwest Atlantic Ocean belong to a single stock unit with a probable common area of origin. Specimens captured in the South and Southeast regions of Brazil had heterogeneous phenotypic attributes regarding otolith shape, probably determined by a temporal equilibrium selection process.
•Shape and microchemical analysis of skipjack tuna otoliths were analyzed.•Otoliths are characterized by complex and variable shapes that differentiate three morphotypes.•Chemical analysis suggests a common area of origin.•Skipjack comprise a single stock in the southwest Atlantic Ocean.
¿Cómo aproximarnos a los procesos históricos a través de los cuales los paneles rupestres fueron construidos y modificados? ¿Cómo integrar esas historias de pintado/grabado al resto de las prácticas ...sociales ejecutadas a su alrededor a lo largo del tiempo? Este artículo tiene como objetivo destacar la relevancia de dichos interrogantes y describir una metodología que permite comenzar a responderlos a partir de la combinación de múltiples niveles de análisis con cinco líneas de evidencias diferentes: análisis espaciales, estudios de las superposiciones entre figuras, estudios estilísticos, análisis químicos de las mezclas pigmentarias y excavación estratigráfica de los depósitos sedimentarios en los pisos de los abrigos. Se presentan, a modo de ejemplo, los resultados alcanzados en la investigación del arte rupestre del sitio arqueológico de Oyola, en la Sierra de El Alto-Ancasti del Noroeste Argentino, aunque la articulación metodológica y técnica podría ser útil a la investigación de otros sitios.
How can we approach the process through which rock art panels have been built and modified? How to connect these histories of painting/engraving with the others social practices performed in the caves though the time? The goal of this article is to remark the importance of these questions and describe a methodology intended to solve them through the combination of multiple levels of analysis, with five different lines of evidence (spatial analysis, overlapping studies, morphologic-stylistic studies, analysis of pigment mixtures and the stratigraphic excavation of the floor’s sediments). As an example, we present the results obtained by the application of this methodology to the study of the rock art from El Alto-Ancasti’s Sierra; however the methods and techniques could be useful for the research of other sites.
The meaning of the names of Greek-Roman collyria is often confusing. Indeed, these names are generally neologisms known to us through a single handwritten or epigraphic occurrence. However, there is ...no doubt that several of these names have been chosen for their for their commercial value, as “ambrosial”, “inimitable” or “invincible”. Did the names of collyria evoking colours have the same value? By virtue of the principle of analogy that prevailed in ancient medical reasoning, were not green, white and yellow considered to be the active ingredients of certain ancient collyria?
The aim of the research was to obtain new information about the genesis, status, diagnostic features, and properties of the meadow-boggy soils of the Azerbaijan Republic and to perform the taxonomic ...attribution of those soils in accordance with the international soil classification system in compliance with the world reference base (WRB) for soil resources. Field experiments, physical, and chemical analyses of soil samples were carried out by standard methods. The morphological properties of the meadow-boggy soils in the Greater Caucasus and Lankaran regions of Azerbaijan have been characterized. Carbonate sediments are almost always invisible in the upper layers (13.27-17.14% (No 426); 10.46-27.39% (No 5); 0.87-1.33% (No 55)). According to the humus content, they are not highly humic (1.44-1.85% (No 426); 0.90-1.58% (No 5); 3.10-3.29% (No 55) in the upper layers). The magnitude of the reaction of the soil solution varies from 8.0 to 8.5. For the first time, an attempt is made to determine the name of meadow-boggy soils in accordance with the international soil classification in compliance with the WRB 2015. The above soils are assigned to the gleysols reference soil group (RSG) with various principal and supplementary qualifiers.
Cannabis sativa subsp. sativa L. is an industrial plant that has gained importance due to its essential oil (EO), which has commercial, medical, and potential cosmetic applications. Despite its ...significance, the chemical constituents of the C. sativa EO cultivated in Morocco is not well understood. In this context, the current study aimed to define and analyze the volatile fraction and evaluate the antioxidant capacity of the plant C. sativa EO for the first time in the Al-Hoceima province in northern Morocco. To assess its chemical composition, gas chromatography-mass spectrometry (GC-MS) was utilized after hydrodistillation using a Clevenger-style apparatus. The analysis revealed that caryophyllene, α-humulene, and β-myrcene were the major constituents, accounting for 31.77%, 11.21%, and 8.76% of the EO, respectively. Antioxidant activity results indicate that the potency of C. sativa EO is interesting (IC 50 = 4.45 mg/mL) for the DPPH● (2,2-diphenyl-1-picrylhydrazyl) test. These findings indicate that the C. sativa EO may serve as a natural source of antioxidants.
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