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China is the most important steel producer in the world, and its steel industry is one of the most carbon-intensive industries in China. Consequently, research on carbon emissions from the steel industry is crucial for China to achieve carbon neutrality and meet its sustainable global development goals. We constructed a carbon dioxide (CO2) emission model for China's iron and steel industry from a life cycle perspective, conducted an empirical analysis based on data from 2019, and calculated the CO2 emissions of the industry throughout its life cycle. Key emission reduction factors were identified using sensitivity analysis. The results demonstrated that the CO2 emission intensity of the steel industry was 2.33 ton CO2/ton, and the production and manufacturing stages were the main sources of CO2 emissions, accounting for 89.84% of the total steel life-cycle emissions. Notably, fossil fuel combustion had the highest sensitivity to steel CO2 emissions, with a sensitivity coefficient of 0.68, reducing the amount of fossil fuel combustion by 20% and carbon emissions by 13.60%. The sensitivities of power structure optimization and scrap consumption were similar, while that of the transportation structure adjustment was the lowest, with a sensitivity coefficient of less than 0.1. Given the current strategic goals of peak carbon and carbon neutrality, it is in the best interest of the Chinese government to actively promote energy-saving and low-carbon technologies, increase the ratio of scrap steel to steelmaking, and build a new power system.
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Dióxido de Carbono , Pegada de Carbono , Aço , China , Dióxido de Carbono/análise , Poluentes Atmosféricos/análise , Metalurgia , Monitoramento Ambiental , Indústrias , Poluição do Ar/estatística & dados numéricos , Poluição do Ar/prevenção & controleRESUMO
The Irish Sea and the Baltic Sea are nowadays still the two most Cs-137 contaminated Seas worldwide. However, the origins of this contaminations are completely different. While the Baltic Sea was unintentionally contaminated due to global fallout after the accident in the Chernobyl nuclear powerplant in 1986, the Irish sea was intentionally used for low level liquid radioactive waste discharges from the Sellafield nuclear reprocessing facility (called Windscale until 1981) between the 1950s and 1990s. Nowadays, more than 30 years later, it is still possible to detect these contaminations in fish, water and sediments of both seas. Since fish are an important part of the human diet, monitoring Cs-137 levels in fish is essential for assessing the potential radiation exposure to humans. In 2019 and 2020 two surveys were dedicated to study the current levels of radioactive contamination in fish species from both Seas. During both surveys, fish samples were collected and analysed by gamma spectrometry later on. The results show that the average Cs-137 activity in benthic, demersal and pelagic fish species from the Baltic Sea are 2.7, 4.6 and 4.2, respectively, times higher than the corresponding values of the Irish Sea. Based on this and two other comparisons, it is concluded that the Baltic Sea is the most contaminated with Cs-137.
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Nitrogen and phosphorus excretion are major sources of environmental contamination in growing-finishing pig operations. Nutrient excretion can be reduced by feeding pigs daily-tailored diets to their estimated nutrient requirements using individual precision feeding (IPF) techniques. This study modeled and evaluated the environmental impact of moving from conventional group three-phase feeding (CGF) to IPF systems in Quebec, Canada, using life-cycle assessment with Simapro software. The cradle-to-farm model included inputs and outputs of each sub-phase: raw materials/feedstuffs production, feed mill processing, transport, animal rearing, and manure management. The model was identical for both treatments in all aspects except for the production of feeds and barn and manure emissions in the growing-finishing phases. All feed ingredients originated from Quebec, simulating agricultural practices using real management data from an average farm in Quebec. Based on observed pig growth data, the CGF and IPF systems were compared in the growing-finishing phase. IPF diets were modeled as the blend of two feeds (i.e. A and B), while CGF diets were stablished according to the industry. The evaluated impact categories were global warming potential (GWP), eutrophication potential (EP), and acidification potential (AP). The functional unit was 1 tonne of feed at the feed mill gate and 1 tonne of finished pig live weight at the farm gate. A Monte Carlo analysis determined the uncertainty of the growth performance results. Feeding programs were compared using analysis of variance. Corn was associated with elevated GWP and AP impacts, leading to higher impacts for diets with higher corn content. Feed B, which contained 83% corn, resulted in impacts of 645 kg of CO2-eq., 8.53 kg SO2-eq., and 4.89 kg PO4-eq. Diets with higher EP impact had a higher percentage of soybean meal. Feed A contained 25% of this ingredient and had an impact of 608 kg CO2-eq., 6.98 kg SO2-eq., and 5.57 kg PO4-eq. CGF diets had environmental impacts between those of feeds A and B. Compared to CGF, applying IPF programs during the growing-finishing phase decreased GWP by 7.6%, AP by 16.2% and EP by 13.0%. IPF significantly reduced the environmental impact in all categories through the more efficient use of nutritional resources by pigs. IPF could help to improve the sustainability of growing-finishing pig operations in Quebec and likely other regions using corn and soybean-based diets.
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BACKGROUND: Devices measuring the macronutrient content of human milk are commonly used to assist with clinical decision-making. It is unknown if these devices accurately measure protein content in donor human milk (DHM). Our objective is to quantify the nitrogen sources and protein content in commercial DHM. METHODS: The total nitrogen content (Dumas method) and nonprotein nitrogen content (Kjeldahl method) was measured in triplicate from six commercial DHM samples with protein content noted on the labels. In addition, the amino acid content was measured in 15 commercial DHM samples and protein content in each sample was calculated. The calculated protein content for each DHM sample was compared for consistency. RESULTS: The nonprotein nitrogen content in DHM was consistently higher (0.33 ± 0.05 g/g) than previous reports, leading to overreporting of protein content on DHM labels by a median value of 0.15 g/dl (range 0.02-0.23 g/dl). Similarly, calculation of the protein content from the total nitrogen content with an assumption of 20% (grams per gram) nonprotein nitrogen consistently overrepresented the protein content as determined from the amino acid profile for DHM. CONCLUSION: Common methods for assessing the macronutrient content of human milk may overestimate the protein content of DHM.
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Requiring no fuel for generation and negligible material/energy for operation and maintenance, photovoltaic (PV) systems have environmental impacts mostly due to the production of modules and the commissioning of power plants. Thus, extending the service lifetime of these systems from 30 to 40 years through an enhanced lamination process for module production potentially reduces environmental impacts per unit energy generated. Life cycle assessment is employed to evaluate the environmental impacts under scenarios for resource utilizations for the new lamination process, operation and maintenance requirements in the extended service lifetime, and degradation rates of the devised modules. Extending the service lifetime significantly reduces environmental impacts across categories, with a 21-27% reduction in global warming potential on the pessimistic and optimistic ends. At least 20% impact reduction is achieved in most impact categories, even under a pessimistic scenario. Considering uncertainty models in the life cycle inventories, samples are generated for scenarios via Monte Carlo simulation, and with significant improvements with large effects in most environmental impact categories, deterministic impact comparisons are supported by ANOVA and Tukey tests. Production strategies for more durable and reliable PV modules have a significant potential in contributing to global sustainability efforts.
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Biochar application is an effective strategy to address Agro-climatic challenges. However, the agro-environmental impacts of different biochar technology models are lacking of systematic summaries and reviews. Therefore, this paper comprehensively reviews recent developments derived from published literature, delving into the economic implications and environmental benefits of three distinct process namely technologies-pyrolysis, gasification, and hydrothermal carbonization. This paper specifically focuses on the agricultural life cycle assessment (LCA) methodology, and the influence of biochar preparation technologies and products on energy consumption and agricultural carbon emissions. LCA analysis shows that process and feedstock pose a predominant role on the properties and production rate of biochar, while gasification technology exhibits excellent economic attributes compared to the other two technologies. Biochar applications in agricultural has the beneficial effect of sequestering carbon and reducing emissions, especially in the area of mitigating the carbon footprint of farmland. However, the complexity of the composition of the prepared feedstock and the mismatch between the biochar properties and the application scenarios are considered as potential sources of risks. Notably, mechanism of carbon sequestration and emission reduction by soil microorganisms and agro-environmental sequestration by biochar application remains unclear, calling for in-depth studies. We review novel aspects that have not been covered by previous reviews by comparing the technical, economic, and environmental benefits of pyrolysis, gasification, and hydrothermal carbonization systematically. Overall, this study will provide a valuable framework to environmental implications of biochar preparation, application, and life cycle assessments.
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In response to global challenges in resource supply, many industries are adopting the principles of the Circular Economy (CE) to improve their resource acquisition strategies. This paper introduces an innovative approach to address the environmental impact of waste Glass Fiber Reinforced-Polymer (GFRP) pipes and panels by repurposing them to manufacture structural components for new bicycle and pedestrian bridges. The study covers the entire process, including conceptualization, analysis, design, and testing of a deck system, with a focus on the manufacturing process for a 7-m-long prototype bridge. The study shows promising results in the concept of a sandwich structure utilizing discarded GFRP pipes and panels, which has the flexibility to account for variabilities in dimensions of incoming products while still meeting mechanical requirements. The LCA analysis shows that the transportation of materials is the governing contributing factor. It was concluded that further development of this concept should be accompanied by a business model that considers the importance of the contributions from the whole value chain.
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Polímeros , Polímeros/química , Reciclagem , Pedestres , Meios de Transporte , Vidro/químicaRESUMO
Husks of rice (RH), coffee (CH), and cholupa (CLH) were used to produce natural adsorbents. The natural adsorbents were used to remove pharmaceuticals such as diclofenac, ciprofloxacin, and acetaminophen in a mixture of distilled water. However, CH stood out for its efficiency in removing ciprofloxacin (74%) due to the higher concentration of acidic groups, as indicated by the Boehm method. In addition, CH removed 86% of ciprofloxacin individually. Therefore, CH was selected and used to remove other fluoroquinolones, such as levofloxacin and Norfloxacin. Although electrostatic interactions favored removals, better removal was observed for ciprofloxacin due to its smaller molecular volume. Then, ciprofloxacin was selected, and the effect of pH, matrix, and adsorbent doses were evaluated. In this way, using a pH of 6.2 in urine with a dose of 1.5 g L-1, it is possible to adsorb CIP concentrations in the range (0.0050-0.42 mmol L-1). Subsequently, the high R2 values and low percentages of APE and Δq indicated better fits for pseudo-second-order kinetics, suggesting a two-stage adsorption. At the same time, the Langmuir isotherm recommends a monolayer adsorption with a Qm of 25.2 mg g-1. In addition, a cost of 0.373 USD/g CIP was estimated for the process, where the material can be reused up to 4 times with a CIP removal in the urine of 51%. Consequently, thermodynamics analysis showed an exothermic and spontaneous process with high disorder. Furthermore, changes in FTIR analysis after adsorption suggest that CH in removing CIP in urine involves electrostatic attractions, hydrogen bonds and π-π interactions. In addition, the life cycle analysis presents, for the 11 categories evaluated, a lower environmental impact of the CIP removal in urine with CH than for the preparation of adsorbent, confirming that the adsorption process is more environmentally friendly than materials synthesis or other alternatives of treatments. Furthermore, future directions of the study based on real applications were proposed.
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Construction and demolition waste (C&DW) represents a pressing concern within the European Union, underscoring the urgent need for effective waste management strategies. The selection of these solutions constitutes a complex task, entailing the identification of efficient C&DW management strategies that balance appropriate practices, regulatory compliance, resource conservation, economic feasibility, and environmental considerations. LCA is widely utilized to assess environmental impact, yet the economic aspect has not been adequately incorporated into the LCA process in the field of C&DW management. The life cycle costing (LCC) methodology has been tailored to assess economic performance in conjunction with LCA. The selection of an appropriate multi-criteria decision-making (MCDM) method is vital for the C&DW system. This study proposes a novel framework for C&DW management by integrating LCA and LCC outcomes into MCDM, using AHP for weight determination, and applying TOPSIS to identify the favorable alternative. Four waste management alternatives were examined in the Lombardy region of Italy, namely (i) landfill; (ii) recycling for concrete production and road construction, incineration with energy recovery; (iii) recycling for road construction; (iv) recycling for concrete production and road construction. We determine that, with the implementation of various scenarios, the most suitable scenario emerges to be recycled for concrete production and road construction, with a score of 0.711/1; recycling for road construction with final score 0.291/1, ranks second; recycling for concrete production and road construction, incineration with energy recovery scores 0.002/1, ranks third; and landfill (scores: 0/1) is the worst choice, signifying it has the highest environmental impacts and the least economic benefits. Lastly, recommendations were formulated to enhance the environmental performance of the system.
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Annually, 8.3 million tonnes of mismanaged plastic waste enter oceans, prompting the food packaging industry, a major contributor, to minimize its environmental footprint. Within the seafood sector, a nascent number of studies are exploring the impacts of various packaging solutions for distribution, yet clear insights remain elusive. This study tries to fill the gap by comparing the impacts of two seafood packaging options: disposable expandable polystyrene (EPS) boxes and, for the first time, reusable plastic crates (RPC) crafted from high-density polyethylene. Using the life cycle assessment methodology with a 'cradle to grave' approach, the research evaluates the distribution of 1260,000â¯t of fish from port of Vigo (Spain) to various markets. Similar climate change values emerge in local (5.00·107â¯kg CO2 eq.) and regional trade (1.20·108â¯kg CO2 eq.) for both options, but RPCs exhibit around a 12â¯% increase (6.15·108â¯kg CO2 eq.) during national distribution, emphasizing package weight and load significance. The findings across all impact categories exhibited general consistent trends. The sensitivity analysis suggests relocating washing facilities to port could enhance RPCs´ environmental benefits for transport within a 160â¯km range. These findings underscore reusable packaging's potential as an eco-friendlier alternative in specific contexts, aligning with heightened environmental concerns and regulatory pressures surrounding plastic usage.
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This research analyses 24 years of oil extraction in blocks 16 and 67 of the Yasuní National Park (YNP) in the Amazonian Forest of Ecuador, one of the most biodiverse spaces in the world and with the current presence of ancient indigenous communities. As a novel contribution, we have carried out a Life-Cycle Assessment (LCA) that quantifies the footprints associated with the extraction, transportation, refining, distribution and final uses of the oil in four different scenarios (oil for asphalt use, electricity, marine fuel and passenger car transport). This study also sheds light on the energy return at the point of use of different oil-derivatives, and complements this with a qualitative analysis of the social, cultural and environmental implications for the Waorani communities. We conclude that the environmental burdens of the extraction process in blocks 16 and 67 in 2015 were greater than those of countries such as the United States, Saudi Arabia and Indonesia, based on the analysis of 11 impact categories. The blocks' operation is the most unfavourable for the categories of Terrestrial Acidification Potential (TAP), Global Warming Potential (GWP), Terrestrial Ecotoxicity Potential (TEP) and Ecosystem Quality Loss Potential (EQL), with increments of 804.15 %, 105.36 %, 506.29 % and 210.73 %, respectively, in relation to the average of the rest of the extraction systems analysed. Specifically, the present case study shows 75.18 % higher impacts in the blocks addressed, when compared to the Ecuadorian average. During the period 1999-2022, the carbon emissions associated with the oil extraction in these blocks have increased by 139.01%. It has been detected a neo-colonial economic behaviour: while the Ecuadorian state received 21% of the sales, the Spanish government and the oil companies received, on average, 38% and 41% of the per-litre average fuel price, respectively. Thus, 79% of the income stayed in the Global North. We conclude that, on average, 19.64 % of the impacts associated with crude oil production and consumption occur in the Amazonian region of the YNP, depending on the fuel used and the consumption mechanism. For the Global Warming Potential (GWP) impact category, the extraction process carries, on average, 34.51 % of the weight in all of the life-cycle impacts, depending on the consumption scenario. It was also estimated that to be able to use 0.33 kWh of electricity from fuel combustion, 0.47 kWh of energy for goods transport and 0.20 kWh for passenger transport, an investment of 1 kWh is required, with an average extended EROI of 1:3.33. According to the qualitative analysis performed, it has been concluded that the main local impacts are related to the obstacles in environmental monitoring and information, the economic dependence of the communities on the oil extraction company, and cultural transformations; impacts that are not easily quantifiable or detectable using other methodologies. The combination of the qualitative analysis and LCA showed that the neo-colonial economic distribution did not compensate the social and environmental impacts of the oil extraction occurred in the YNP.
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Galactosomum nagasakiense n. sp. (Digenea: Heterophyidae), the causative parasite of trematode whirling disease of marine fish, is described, based on the specimens collected from the black-tailed gull, Larus crassirostris in Nagasaki Prefecture, Japan. The new species belongs to the cochleariformum group, and is different from the three species in the group: G. cochleare (Diesing, 1850) in the larger oral sucker and phaynx and smaller eggs, G. cochleariformum (Rudolphi, 1819) in the smaller oral sucker and pharynx and smaller eggs, and G. spinetum (Braun, 1901) in the uterus which extends anterior to the ventrogenital sac. Metacercariae collected from the brain of several marine fish developing trematode whirling disease are also described. Considering low host specificity of the second intermediate hosts, the endemic nature of the trematode whirling disease may be attributed to the infection of a particular population of the final host and/or a limited geographical distribution of the first intermediate host.
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Most teleost fishes exhibit a biphasic life history with a larval oceanic phase that is transformed into morphologically and physiologically different demersal, benthic, or pelagic juveniles. This process of transformation is characterized by a myriad of hormone-induced changes, during the often abrupt transition between larval and juvenile phases called metamorphosis. Thyroid hormones (TH) are known to be instrumental in triggering and coordinating this transformation but other hormonal systems such as corticoids, might be also involved as it is the case in amphibians. In order to investigate the potential involvement of these two hormonal pathways in marine fish post-embryonic development, we used the Malabar grouper (Epinephelus malabaricus) as a model system. We assembled a chromosome-scale genome sequence and conducted a transcriptomic analysis of nine larval developmental stages. We studied the expression patterns of genes involved in TH and corticoid pathways, as well as four biological processes known to be regulated by TH in other teleost species: ossification, pigmentation, visual perception, and metabolism. Surprisingly, we observed an activation of many of the same pathways involved in metamorphosis also at an early stage of the larval development, suggesting an additional implication of these pathways in the formation of early larval features. Overall, our data brings new evidence to the controversial interplay between corticoids and thyroid hormones during metamorphosis as well as, surprisingly, during the early larval development. Further experiments will be needed to investigate the precise role of both pathways during these two distinct periods and whether an early activation of both corticoid and TH pathways occurs in other teleost species.
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Larva , Metamorfose Biológica , Animais , Metamorfose Biológica/genética , Larva/crescimento & desenvolvimento , Larva/genética , Larva/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Transcriptoma , Perfilação da Expressão Gênica , Bass/genética , Bass/crescimento & desenvolvimento , Bass/metabolismo , Hormônios Tireóideos/metabolismoRESUMO
Recycled aggregate concrete (RAC), mainly made from recycled materials such as construction and demolition waste (CDW), has emerged as a sustainable alternative to natural aggregate concrete (NAC). While RAC offers potential benefits in waste reduction and resource conservation, a comprehensive understanding of its environmental impact and sustainability compared to NAC has been lacking. This study addresses this gap by conducting a thorough review and analysis of comparative Life Cycle Assessment (LCA) studies between RAC and NAC. This paper synthesizes current literature to evaluate the environmental impact of both materials throughout their life cycles, from raw material extraction to disposal. It examines key factors such as energy consumption, greenhouse gas emissions, and resource depletion to provide a thorough comprehension of the effects on the environment of each concrete type throughout their life cycles. Challenges in using RAC as a sustainable concrete option, such as sourcing and quality control, are also discussed, along with recommendations for future research and industry practices. The findings indicate that the environmental impact of RAC compared to NAC is significantly influenced by transport distances and modes. In addition, the choice of functional units in LCAs substantially affects the comparison between RAC and NAC, with strength reliability offering a clear benefit by addressing concrete property variability and better reflecting real-world conditions.
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Contaminated sediments may induce long-term risks to humans and ecosystems due to the accumulation of priority and emerging inorganic and organic pollutants having toxic and bio-accumulation properties that could become a secondary pollution source. This study focused on the screening of novel bio-based materials to be used in the decontamination of marine sediments considering technical and environmental criteria. It aimed to compare the environmental impacts of cellulose-based adsorbents produced at lab scale by using different syntheses protocols that involved cellulose functionalization by oxidation and branching, followed by structuring of an aerogel-like material via Soxhlet extraction and freeze-drying or their combination. As model pollutants, we used 4-nitrobenzaldehyde, 4-nitrophenol, methylene blue, and two heavy metals, i.e., cadmium and chromium. When comparing the three materials obtained by only employing the Soxhlet extractor with different solvents (without freeze-dying), it was observed that the material obtained with methanol did not have a good structure and was rigid and more compact than the others. A Life Cycle Assessment (LCA) was conducted to evaluate the environmental performance of the novel materials. Apart from the hierarchical categorization of the materials based on their technical and environmental performance in eliminating organic pollutants and heavy metal ions, it was demonstrated that the cellulose-based material obtained via Soxhlet extraction with ethanol was a better choice, since it had lower environmental impacts and highest adsorption capacity for the model pollutants. LCA is a useful tool to optimize the sustainability of sorbent materials alongside lab-scale experiments and confirms that the right direction to produce new performant and sustainable adsorbent materials involves not only choosing wastes as starting materials, but also optimizing the consumption of electricity used for the production processes. The main results also highlight the need for precise data in LCA studies based on lab-scale processes and the potential for small-scale optimization to reduce the environmental impacts.
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Fungal primary pathogenicity on vertebrates is here described as a deliberate strategy where the host plays a role in increasing the species fitness. Opportunism is defined as coincidental survival of an individual strain in host tissue using properties that are designed for life in an entirely different habitat. In that case the host's infection control is largely based on innate immunity, and the etiologic agent is not transmitted after infection, and thus fungal evolution is not possible. Primary pathogens encompass two types, depending on their mode of transmission. Environmental pathogens have a double life cycle, and tend to become enzootic, adapted to a preferred host in a particular habitat. In contrast, pathogens that have a host-to-host transmission pattern are prone to shift to a neighboring, immunologically naive host, potentially leading to epidemics. Beyond these prototypical life cycles, some environmental fungi are able to make large leaps between dissimilar hosts/habitats, probably due to similarity of key factors enabling survival in an entirely different niche, and thus allowing a change from opportunistic to primary pathogenicity. Mostly, such factors seem to be associated with extremotolerance.
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Increased anthropogenic activities over the last decades have led to a gradual increase in chromium (Cr) content in the soil, which, due to its high mobility in soil, makes Cr accumulation in plants a serious threat to the health of animals and humans. The present study investigated the ameliorative effect of foliar-applied Si nanoparticles (SiF) and soil-applied SiNPs enriched biochar (SiBc) on the growth of wheat in Cr-polluted soil (CPS). Two levels of CPS were prepared, including 12.5 % and 25 % by adding Cr-polluted wastewater in the soil as soil 1 (S1) and soil 2 (S2), respectively for the pot experiment with a duration of 40 days. Cr stress significantly reduced wheat growth, however, combined application of SiF and SiBc improved root and shoot biomass production under Cr stress by (i) reducing Cr accumulation, (ii) increasing activities of antioxidant enzymes (ascorbate peroxidase and catalase), and (iii) increasing protein and total phenolic contents in both root and shoot respectively. Nonetheless, separate applications of SiF and SiBc effectively reduced Cr toxicity in shoot and root respectively, indicating a tissue-specific regulation of wheat growth under Cr. Later, the Langmuir and Freundlich adsorption isotherm analysis showed a maximum soil Cr adsorption capacity â¼ Q(max) of 40.6 mg g-1 and 59 mg g-1 at S1 and S2 respectively, while the life cycle impact assessment showed scores of -1 mg kg-1 and -211 mg kg-1 for Cr in agricultural soil and - 0.184 and - 38.7 for human health at S1 and S2 respectively in response to combined SiF + SiBC application, thus indicating the environment implication of Si nanoparticles and its biochar in ameliorating Cr toxicity in different environmental perspectives.
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Complete retention lagoons with wastewater reuse for agricultural purposes may offer sustainability advantages over alternative systems for small communities in semiarid regions. This study quantifies the environmental life cycle impact of adopting agriculture water reuse systems using case study data to estimate operating and building infrastructure impacts and spatial-temporal modeling to quantify resource trade-offs. Water reuse system benefits are highly dependent on supply-storage-demand dynamics. The relative size of irrigated agricultural land to the lagoon size was the most significant factor influencing site water application rates. The benefits are sensitive to changes in air emissions occurring from the agricultural land and further emphasize the importance of proper fertilizer management when adopting water reuse systems. Wastewater reuse from complete retention lagoons reduce life cycle GHG emissions, primarily through excavation reductions, offset fertilizer use, and especially from increased crop yields from wastewater reuse at previously rainfed sites. PRACTITIONER POINTS: Seven case studies and spatial-temporal modeling quantified resource trade-offs for water reuse to reduce lagoon size. Excavation reductions and offset fertilizer compensated for emissions from electricity and construction. Crop yield increases were the largest environmental benefit of adopting water reuse. System benefits are highly dependent on supply-storage-demand dynamics. Designers should use climatic data to help estimate potential variability in available water for reuse and associated energy and crop production.
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Modelos Teóricos , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos , Agricultura/métodos , Reciclagem , Conservação dos Recursos Naturais/métodosRESUMO
Background: Healthcare is responsible for 4% to 10% of carbon emissions worldwide, of which 22% is related to transport. Telemedicine emerged as a potential solution to reduce the footprint, for example, by reducing travel. However, a need to understand which variables to include in carbon footprint estimations in telemedicine limits our understanding of the beneficial impact telemedicine might have on our environment. This paper aims to systematically assess the reported carbon footprint and include variables assessed by the literature, comparing telemedicine with usual care. Methods: The systematic review followed the PRISMA guidelines in PubMed, Medline, Embase and Scopus. A quality assessment was performed using a transparency checklist for carbon footprint calculators. Carbon emissions were evaluated based on four categories, including patient travel, and streamlined life cycle assessment (LCA) for assessing included variables relevant to telemedicine. Results: We included 33 articles from 1117 records for analysis. The average transparency score was 38% (range 18%-68%). The median roundtrip travel distance for each patient was 131 km (interquartile range [IQR]: 60.8-351), or 25.6 kgCO2 (IQR: 10.6-105.6) emissions. There is high variance among included variables. Saved emissions are structurally underestimated by not including external factors such as a streamlined LCA. Conclusions: Telemedicine aids in reducing emissions, with travel distance being the most significant contributor. Additionally, we recommend accounting for the LCA since it highlights important nuances. This review furthers the debate on assessing carbon footprint savings due to telemedicine.
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Today, one of the major challenges of dairy farmers is to reduce their environmental footprint to establish more effective, efficient, and sustainable production systems. Feed additives such as yeast probiotics could potentially allow them to achieve these objectives through the improvement of milk production, feed efficiency, and ration valorization, hence mitigating the environmental impacts of milk production. In this study, the life cycle assessment (LCA) principle was performed to estimate the environmental impact of the production and supplementation of a commercial yeast probiotic (Actisaf Sc 47) in three trials performed in three different countries that are representative for around 50% of the milk production in Europe: France (French trial), United Kingdom (UK trial), and Germany (German trial). For each trial, two groups of animals were compared: control, without Actisaf Sc 47 supplementation, used as baseline; and experimental, with Actisaf Sc 47 supplementation at 5 or 10 g/cow/day. Different impact categories were analyzed for each group to calculate the impact of producing 1 kg of fat- and protein-corrected milk. An initial analysis was done only during the period of Actisaf Sc 47 supplementation and showed than the supplementation with Actisaf Sc 47 reduced, on average by 5%, the carbon footprint during the three trials. A second analysis was done via the extrapolation of all the data of each trial to an annual farm level, including the lactation period (305 days), dry period (60 days), and the period with and without Actisaf Sc 47 supplementation. Reported at a farm annual scale, the average reduction allowed by Actisaf Sc 47 supplementation was 2.9, 2.05, 2.47, 1.67, 2.28, 2.18, 2.14, and 2.28% of the carbon footprint, land use, water use, resource use, acidification, freshwater eutrophication, marine eutrophication, and terrestrial eutrophication, respectively. On average, the production of 1 kg of fat- and protein-corrected milk by using Actisaf Sc 47 was shown to improve environmental impacts compared to control. Regarding Actisaf Sc 47 production, the LCA showed that the production of 1 kg of Actisaf Sc 47 emitted 2.1 kg CO2 eq with a negligible contribution to total the carbon footprint of milk ranging from 0.005 to 0.016%. The use of Actisaf Sc 47 in dairy cows could then result in different positive outcomes: improving performance and efficiency while reducing the global carbon footprint.