1,721,028 research outputs found
A GIS-based approach for detecting pollution sources and bioavailability of metals in coastal and marine sediments of Chabahar Bay, SE Iran
No full textChabahar Bay in SE of Iran is a shallow semi-enclosed environment affected by anthropogenic activities. In this paper, 19 sediment samples were collected and concentration of selected metals (Cu, Pb, Zn, Cd, Ni, Cr, Co, V and Fe) was determined using ICP-MS analytical method. Sediment samples from five stations were also selected for sequential extraction analysis and concentration of metals in each fraction was determined using ICP-OES. In order to investigate the environmental quality of Chabahar Bay, geographic information system (GIS) along with geochemical data, environmental indices and statistical analyses were used. Calculated contamination degree (Cd) revealed that most contaminated stations (Ch3, S1 and S3) are located SE of Chabahar Bay and contamination decreases in a NW direction. The S9 station, west of the bay, is also contaminated. High organic matter (OM) content in the sediments is most likely the result of fuel and sewage discharge from fishing vessels along with discharge of fishing leftovers. Significant correlation coefficient among OM, Fe, Cu, Pb, Zn and Cd seemingly reflects the importance of the role that OM and Fe oxy-hydroxides play in the metals mobility. The results of hierarchical cluster analysis (HCA), computed correlation coefficient and sequential extraction analysis suggest that Cu, Pb, Zn and Cd probably come from antifouling and sea vessel paints, while Ni, Cr, Co, V and Fe are most likely contributed by ophiolitic formations located north of the bay and/or deep sea sediments. Average individual contamination factors (ICFs) indicated that the highest health hazard from the bay is posed by Cu, Pb and Zn
Unlocking the biorefinery approaches to valorize sugar beet leaves (B. Vulgaris L.) for food industry applications: A critical review
Full text linkThe large-scale cultivation of sugar beets generates a significant amount of by-products,
particularly leaves, which are often overlooked and wasted. However, these by-products are a
valuable source of functional compounds that can be repurposed to enhance crop
sustainability and produce food ingredients. Therefore, valorization of sugar beet leaves
(SBLs) is a prudent biorefinery approach for future utilization. This literature review
highlights the significant advances in valorizing SBLs for food industry applications. The
extractable phytochemical compounds, the sustainability and challenges of recovery, the
extraction methods, potential health benefits, current applications, and prospective
valorization possibilities of SBLs within a circular economy framework were reviewed. The
results showed that SBLs are rich in nutrients and bioactive phytochemicals such as
polyphenols (e.g., flavonoids and phenolic acids), proteins, essential amino acids,
chlorophylls, fiber, and essential fatty acids. The application of these compounds in the
development of food products may exhibit numerous health benefits, including antioxidant,anti-microbial, anti-inflammatory, anti-diabetic, and anti-cancer properties. However, for potential applications of SBLs in the food industry to develop functional foods, nutritional supplements, and natural food additives, further research is needed to optimize the efficient extraction of functional compounds on an industrial scale and to verify the safety of extracted compounds for human consumption
Protein-polyphenol complexation vs. conjugation: A review on mechanisms, functional differences, and antioxidant-emulsifier roles
Full text linkThe interaction between proteins and polyphenols has gained attention for improving the stability and physicochemical properties of colloidal systems. This review focuses on recent advances in their interaction mechanisms and functional impacts. Protein-polyphenol assemblies are formed through covalent bonding (i.e., conjugation) or non-covalent bonding (i.e., complexation). These interactions may lead to distinct functionalities and properties influenced by environmental conditions. The conjugation is usually initiated by the oxidation of polyphenols through alkaline treatment, free radicals, etc., while complexation occurs even under milder conditions, such as neutral pH and room temperature, resulting in weaker and reversible interactions. Despite the significant increase in the number of studies on protein-polyphenol interactions in recent years, there is no clear consensus in the previous literature on whether covalent or non-covalent bonding provides better stability under different processing conditions. In emulsion-based food systems, protein-polyphenol assemblies can function dually as antioxidant-emulsifiers, where proteins provide the emulsifying ability, and polyphenols contribute antioxidant activity. This effect is due to the positioning of these assemblies in the oil-water interface. Understanding the distinct roles and conditions of protein-polyphenol interactions is crucial for optimizing their use in designing stable, functional colloidal systems, particularly in emulsion-based foods
Effect of freeze-drying and ultrasound-assisted extraction on bioactive compounds in beet leaves (Beta vulgaris L.).
No full textGadolinium as an Emerging Microcontaminant in Water Resources: Threats and Opportunities
Full text linkAs a result of high doses of paramagnetic gadolinium (Gd) chelates administered in magnetic resonance imaging (MRI) exams, their unmetabolized excretion, and insufficient removal in wastewater treatment plants (WWTPs), large amounts of anthropogenic Gd (Gdanth) are released into surface water. The upward trend of gadolinium-based contrast agent (Gd-CA) administrations is expected to continue growing and consequently higher and higher anthropogenic Gd concentrations are annually recorded in water resources, which can pose a great threat to aquatic organisms and human beings. In addition, the feasibility of Gd retention in patients administered with Gd-CAs repeatedly, and even potentially fatal diseases, including nephrogenic systemic fibrosis (NSF), due to trace amounts of Gd have recently arisen severe health concerns. Thus, there is a need to investigate probable adverse health effects of currently marketed Gd-CAs meticulously and to modify the actual approach in using Gd contrast media in daily practice in order to minimize unknown possible health risks. Furthermore, the employment of enhanced wastewater treatment processes that are capable of removing the stable contrast agents, and the evaluation of the ecotoxicity of Gd chelates and human exposure to these emerging contaminants through dermal and ingestion pathways deserve more attention. On the other hand, point source releases of anthropogenic Gd into the aquatic environment presents the opportunity to assess surface water—groundwater interactions and trace the fate of wastewater plume as a proxy for the potential presence of other microcontaminants associated with treated wastewater in freshwater and marine systems
Evaluating Hydrogeochemical Processes Regulating Groundwater Quality in an Unconfined Aquifer
No full textHydrogeochemistry of groundwater was investigated to understand groundwater quality for drinking and irrigation purposes in an unconfined aquifer located in Jangal plain, NE Iran. Groundwater samples were collected and analyzed for determining physicochemical parameters (TDS, EC and pH) and concentration of major ions (Na+, K+, Ca2+, Mg2 +, Cl−, HCO3−, SO42 − and CO32 −). Water quality assessment parameters including SAR, Na%, RSC, TH and SI were also calculated. TDS, EC, Na+, K+, Cl− and SO42 − levels in all samples were greater than the maximum permissible limit, while pH, Ca2 +, Mg2 + and HCO3− levels in most samples were within the standard range. Based on the Piper diagram, most groundwater samples were classified into Na-Cl as dominant water type. The saline water intrusion, evapotranspiration, ion exchange reactions and dissolution of carbonate minerals were found as the main processes controlling the chemistry of groundwater. According to the calculated parameters and the Wilcox and USSL diagrams, high salinity and alkalinity of the groundwater resources pose a major problem for irrigation use. It is obvious that the groundwater unsuitability threatens sustainable crop production and soil quality. Hence, urgent management of groundwater resources is suggested to avoid harmful effects on inhabitants
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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