scholarly journals Antimony leaching from mine waste and soil at a stibnite mine in North-Vietnam

2021 ◽  
Author(s):  
Valérie Cappuyns ◽  
Axelle Van Campen ◽  
Jillian Helser
Keyword(s):  
Wind Erosion ◽  
Mine Waste ◽  
Public Awareness ◽  
Mineralogical Composition ◽  
Water Soluble ◽  
Waste Rock ◽  
Waste Materials ◽  
Potential Hazard ◽  
North Vietnam ◽  
The Impact

<p>While the impact of Sb mining is documented in literature from China, Australia, and Europe, little information is available concerning the environmental impact of Sb mining in Vietnam. This paper presents the results of an exploratory study of mine waste and soil samples from the Mau Due mine (North Vietnam). Besides the chemical and mineralogical composition of soils, waste rock and slag samples, water-soluble and exchangeable/reversibly adsorbed Sb species were also determined, as well as the pH dependent release of Sb. Stibnite and pyrite were found in slag and waste rock samples, with total Sb concentrations in the range of 191–15,699 mg/kg. Soils were characterized by Sb concentrations in the range of 47–95 mg/kg. <br>The leaching test show that, when mine waste stored on the Mau Due mining site comes into contact with water, up to 1.7% of its total Sb content is leached. However, because of the high Sb content of some of the waste materials, high dissolved Sb concentrations are found in the leachates. Some of the investigated samples are listed by the EU as absolutely hazardous waste, because of the leaching potential of Sb. Especially in the rainy season, leaching of Sb from the mine waste and slags can contribute to the dispersion of Sb. An increased release of Sb was observed from pH 7.5 to 12.8. Modelling also indicated that the dissolution of stibnite and reprecipitation as Sb(OH)<sub>3</sub> is not the only factor that explains Sb solubility. Desorption reactions and the incorporation of Sb in other mineral phases are most likely also important factors determining the retention and release of Sb from the waste materials and slags.<br>The waste heaps consist of fine-grained material, that can be prone to wind erosion in the dry season. Therefore, measures to prevent the further dispersion of Sb and other potentially hazardous elements, both via leaching and wind erosion, should be put in place. In order to establish regulations for environmental protection, it is necessary to raise governmental and public awareness. The high concentrations of Sb imply an important potential hazard for soils, water bodies, and the food chain, for which appropriate measures are necessary.</p><p> </p><p><strong>Reference</strong></p><p>Cappuyns, V., Van Campen, A., Helser, J.  (2020). Antimony leaching from soils and mine waste from the Mau Due antimony mine, North-Vietnam. Journal Of Geochemical Exploration, 220, Art.No. 106663, 1-13. doi: 10.1016/j.gexplo.2020.106663 </p>

A column study of the impact of layering the different Lac Tio mine waste rock lithologies on drainage water quality

2021 ◽  
pp. 106823
Author(s):  
Bissé Poaty ◽  
Benoît Plante ◽  
Bruno Bussière ◽  
Mostafa Benzaazoua ◽  
Martin Thériault
Keyword(s):  
Water Quality ◽  
Mine Waste ◽  
Drainage Water ◽  
Waste Rock ◽  
Column Study ◽  
Mine Waste Rock ◽  
The Impact

Genetic Variation: Impact on Folate (and Choline) Bioefficacy

2010 ◽  
Vol 80 (45) ◽  
pp. 319-329 ◽  
Author(s):  
Allyson A. West ◽  
Marie A. Caudill
Keyword(s):  
Carbon Metabolism ◽  
Genetic Variants ◽  
Plasma Homocysteine ◽  
Water Soluble ◽  
Gene Interactions ◽  
Dietary Folate ◽  
Methyl Donors ◽  
Common Genetic Variants ◽  
One Carbon Metabolism ◽  
The Impact

Folate and choline are water-soluble micronutrients that serve as methyl donors in the conversion of homocysteine to methionine. Inadequacy of these nutrients can disturb one-carbon metabolism as evidenced by alterations in circulating folate and/or plasma homocysteine. Among common genetic variants that reside in genes regulating folate absorptive and metabolic processes, homozygosity for the MTHFR 677C > T variant has consistently been shown to have robust effects on status markers. This paper will review the impact of genetic variants in folate-metabolizing genes on folate and choline bioefficacy. Nutrient-gene and gene-gene interactions will be considered along with the need to account for these genetic variants when updating dietary folate and choline recommendations.

Effects of Quarantine Due to the COVID-19 on Sleep Duration and Quality in Algerians

2020 ◽  
Vol 60 (2) ◽  
pp. 182-193
Author(s):  
Kacem Abdelhadi ◽  
Houar Abdelatif ◽  
Zerf Mohamed ◽  
Bengoua Ali
Keyword(s):  
Statistical Analysis ◽  
Sleep Quality ◽  
Sleep Duration ◽  
Online Survey ◽  
Public Awareness ◽  
Italian Version ◽  
Sleep Timing ◽  
Algerian Population ◽  
Significant Change ◽  
The Impact

SummaryThis study tests the impact of COVID-19 on sleep of Algerian population before and during the COVID-19 quarantine by an estimated online survey, adapted from the PSQI Italian version. Including 1210 participants (age between 18-60 years old). The statistical analysis was carried out using SPSS version 22.0 software. Our results showed a significant change in sleeping quality during quarantine, the sleep timing markedly changed, we also noticed additional use of sleeping medications. Algerian scientists recommend to build public awareness and to provide necessary information regarding Algerian sleep quality, especially for Algerian adults.

scholarly journals Desiccation time and rainfall control gaseous carbon fluxes in an intermittent stream

2021 ◽  
Author(s):  
Maria Isabel Arce ◽  
Mia M. Bengtsson ◽  
Daniel von Schiller ◽  
Dominik Zak ◽  
Jana Täumer ◽  
...  
Keyword(s):  
Water Soluble ◽  
Intermittent Flow ◽  
Dry Period ◽  
Intermittent Stream ◽  
Aerobic Activity ◽  
Water Soluble Organic Carbon ◽  
Soluble Organic Carbon ◽  
Microbial C ◽  
Global Biogeochemical Cycles ◽  
The Impact

AbstractDroughts are recognized to impact global biogeochemical cycles. However, the implication of desiccation on in-stream carbon (C) cycling is not well understood yet. We subjected sediments from a lowland, organic rich intermittent stream to experimental desiccation over a 9-week-period to investigate temporal changes in microbial functional traits in relation to their redox requirements, carbon dioxide (CO2) and methane (CH4) fluxes and water-soluble organic carbon (WSOC). Concurrently, the implications of rewetting by simulated short rainfalls (4 and 21 mm) on gaseous C fluxes were tested. Early desiccation triggered dynamic fluxes of CO2 and CH4 with peak values of 383 and 30 mg C m−2 h−1 (mean ± SD), respectively, likely in response to enhanced aerobic mineralization and accelerated evasion. At longer desiccation, CH4 dropped abruptly, likely because of reduced abundance of anaerobic microbial traits. The CO2 fluxes ceased later, suggesting aerobic activity was constrained only by extended desiccation over time. We found that rainfall boosted fluxes of CO2, which were modulated by rainfall size and the preceding desiccation time. Desiccation also reduced the amount of WSOC and the proportion of labile compounds leaching from sediment. It remains questionable to which extent changes of the sediment C pool are influenced by respiration processes, microbial C uptake and cell lysis due to drying-rewetting cycles. We highlight that the severity of the dry period, which is controlled by its duration and the presence of precipitation events, needs detailed consideration to estimate the impact of intermittent flow on global riverine C fluxes.

scholarly journals Anthropomorphic Strategies Promote Wildlife Conservation through Empathy: The Moderation Role of the Public Epidemic Situation

2021 ◽  
Vol 18 (7) ◽  
pp. 3565
Author(s):  
Dan Yue ◽  
Zepeng Tong ◽  
Jianchi Tian ◽  
Yang Li ◽  
Linxiu Zhang ◽  
...  
Keyword(s):  
College Students ◽  
Behavioral Intention ◽  
Wildlife Conservation ◽  
Negative Emotion ◽  
Public Awareness ◽  
Negative Emotions ◽  
Experimental Studies ◽  
Wildlife Trade ◽  
Illegal Wildlife Trade ◽  
The Impact

The global illegal wildlife trade directly threatens biodiversity and leads to disease outbreaks and epidemics. In order to avoid the loss of endangered species and ensure public health security, it is necessary to intervene in illegal wildlife trade and promote public awareness of the need for wildlife conservation. Anthropomorphism is a basic and common psychological process in humans that plays a crucial role in determining how a person interacts with other non-human agents. Previous research indicates that anthropomorphizing nature entities through metaphors could increase individual behavioral intention of wildlife conservation. However, relatively little is known about the mechanism by which anthropomorphism influences behavioral intention and whether social context affects the effect of anthropomorphism. This research investigated the impact of negative emotions associated with a pandemic situation on the effectiveness of anthropomorphic strategies for wildlife conservation across two experimental studies. Experiment 1 recruited 245 college students online and asked them to read a combination of texts and pictures as anthropomorphic materials. The results indicated that anthropomorphic materials could increase participants’ empathy and decrease their wildlife product consumption intention. Experiment 2 recruited 140 college students online and they were required to read the same materials as experiment 1 after watching a video related to epidemics. The results showed that the effect of wildlife anthropomorphization vanished if participants’ negative emotion was aroused by the video. The present research provides experimental evidence that anthropomorphic strategies would be useful for boosting public support for wildlife conservation. However, policymakers and conservation organizations must be careful about the negative effects of the pandemic context, as the negative emotions produced by it seems to weaken the effectiveness of anthropomorphic strategies.

scholarly journals A non-toxic, reversibly released imaging probe for oral cancer that is derived from natural compounds

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Magda Ghanim ◽  
Nicola Relitti ◽  
Gavin McManus ◽  
Stefania Butini ◽  
Andrea Cappelli ◽  
...  
Keyword(s):  
Oral Cancer ◽  
Cancer Progression ◽  
Intraoperative Imaging ◽  
Critical Role ◽  
Water Soluble ◽  
Stem Cell Marker ◽  
Squamous Cells ◽  
Tissue Identification ◽  
Tumorigenic Potential ◽  
The Impact

AbstractCD44 is emerging as an important receptor biomarker for various cancers. Amongst these is oral cancer, where surgical resection remains an essential mode of treatment. Unfortunately, surgery is frequently associated with permanent disfigurement, malnutrition, and functional comorbidities due to the difficultly of tumour removal. Optical imaging agents that can guide tumour tissue identification represent an attractive approach to minimising the impact of surgery. Here, we report the synthesis of a water-soluble fluorescent probe, namely HA-FA-HEG-OE (compound 1), that comprises components originating from natural sources: oleic acid, ferulic acid and hyaluronic acid. Compound 1 was found to be non-toxic, displayed aggregation induced emission and accumulated intracellularly in vesicles in SCC-9 oral squamous cells. The uptake of 1 was fully reversible over time. Internalization of compound 1 occurs through receptor mediated endocytosis; uniquely mediated through the CD44 receptor. Uptake is related to tumorigenic potential, with non-tumorigenic, dysplastic DOK cells and poorly tumorigenic MCF-7 cells showing only low intracellular levels and highlighting the critical role of endocytosis in cancer progression and metastasis. Together, the recognised importance of CD44 as a cancer stem cell marker in oral cancer, and the reversible, non-toxic nature of 1, makes it a promising agent for real time intraoperative imaging.

Jam processing: Effect of pectin replacement by locust bean gum on its characteristics

2020 ◽  
pp. 1-12
Author(s):  
Aida Mekhoukhe ◽  
Nacer Mohellebi ◽  
Tayeb Mohellebi ◽  
Leila Deflaoui-Abdelfettah ◽  
Sonia Medouni-Adrar ◽  
...  
Keyword(s):  
Cold Water ◽  
Physicochemical Characteristics ◽  
Water Soluble ◽  
Sensory Profile ◽  
Locust Bean Gum ◽  
Locust Bean ◽  
Preference Map ◽  
The Right ◽  
High Level ◽  
The Impact

OBJECTIVE: the present work proposed to extract Locust Bean Gum (LBG) from Algerian carob fruits, evaluate physicochemical and rheological properties (solubility). It aimed also to develop different formulations of strawberry jams with a mixture of LBG and pectin in order to obtain a product with a high sensory acceptance. METHODS: the physicochemical characteristics of LBG were assessed. The impact of temperature on solubility was also studied. The physical and the sensory profile and acceptance of five Jams were evaluated. RESULTS: composition results revealed that LBG presented a high level of carbohydrate but low concentrations of fat and ash. The LBG was partially cold-water-soluble (∼62% at 25°C) and needed heating to reach a higher solubility value (∼89% at 80 °C). Overall, the sensorial acceptances decreased in jams J3 which was formulated with 100% pectin and commercial one (J5). The external preference map explained that most consumers were located to the right side of the map providing evidence that most samples appreciated were J4 and J2 (rate of 80–100%). CONCLUSION: In this investigation, the LBG was used successfully in the strawberry jam’s formulation.

scholarly journals The Correlation between Physical Crosslinking and Water-Soluble Drug Release from Chitosan-Based Microparticles

Pharmaceutics ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 455
Author(s):  
Emilia Szymańska ◽  
Katarzyna Woś-Latosi ◽  
Julia Jacyna ◽  
Magdalena Dąbrowska ◽  
Joanna Potaś ◽  
...  
Keyword(s):  
Drug Release ◽  
Polymer Matrix ◽  
Drug Loading ◽  
Water Soluble ◽  
Dissolution Behavior ◽  
Complex Nature ◽  
Prolonged Release ◽  
Scanning Calorimetry ◽  
Burst Effect ◽  
The Impact

Microparticles containing water-soluble zidovudine were prepared by spray-drying using chitosan glutamate and beta-glycerophosphate as an ion crosslinker (CF). The Box–Behnken design was applied to optimize the microparticles in terms of their drug loading and release behavior. Physicochemical studies were undertaken to support the results from dissolution tests and to evaluate the impact of the crosslinking ratio on the microparticles’ characteristics. The zidovudine dissolution behavior had a complex nature which comprised two phases: an initial burst effect followed with a prolonged release stage. The initial drug release, which can be modulated by the crosslinking degree, was primarily governed by the dissolution of the drug crystals located on the microparticles’ surfaces. In turn, the further dissolution stage was related to the drug diffusion from the swollen polymer matrix and was found to correlate with the drug loading. Differential Scanning Calorimetry (DSC) studies revealed the partial incorporation of a non-crystallized drug within the polymer matrix, which correlated with the amount of CF. Although CF influenced the swelling capacity of chitosan glutamate microparticles, surprisingly a higher amount of CF did not impact the time required for 80% of the drug to be released markedly. The formulation with the lowest polymer:CF ratio, 3:1, was selected as optimal, providing satisfactory drug loading and displaying a moderate burst effect within the first 30 min of the study, followed with a prolonged drug release of up to 210 min.

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