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Effect of water temperature and food availability on growth performance, sex ratio and gonadal development in juvenile convict cichlid (Amatitlanianigrofasciata) Полный текст
2022
Abdollahpour, Hamed | Falahatkar, Bahram | Van Der Kraak, Glen
Temperature and food availability are key drivers of growth and reproductive development in fishes, but information on how they interact is poorly understood. This study investigates the effects of water temperature and food availability on growth, sex ratio and gonadal development of the convict cichlid (Amatitlania nigrofasciata) which is an ornamental fish that may be a useful lab model. For this experiment, 180 juvenile convict cichlid (0.3 ± 0.02 g) were held at three different temperatures (26, 29 and 32 °C as T1, T2 and T3) and fed to satiation (S) or a restricted diet (R: half satiation) during a 56-day experimental period. Specific growth rate was significantly higher in T2S treatment than the other groups. The highest and lowest mean oocyte sizes were recorded in T1S and T3R groups, respectively. The sex ratio of fish held at 29 °C was male biased (female, 21.0%; male, 78.9%), but this was not seen at 26 °C (female, 47.6%; male, 52.4%) or 32 °C (female, 57.1%; male, 42.9%). In T1S and T1R treatments, oocytes developed more than the other treatments and in T2S group testicular development was more advanced than other groups. These results demonstrate the complex interplay of temperature and food availability on growth and reproductive development in the convict cichlid. Appropriate food availability significantly improves growth and reproductive processes, while restricted feeding decreases growth, survival rate and reproductive performance.
Показать больше [+] Меньше [-]An analysis of the relationship between water-energy-food system and economic growth in China based on ecological footprint measurement Полный текст
2022
Lian-yan Xu | De-chun Huang | Zheng-qi He | Yun Zhu
With the acceleration of urbanization, the demand for water, energy and food (WEF) keeps increasing. However, the infrastructure construction leads to a sharp decline of cultivated land, water area and forest land, so the importance of ecological space management should be recognized. Based on ecological footprint theory, this paper proposes the WEF footprint and first attempts to explicitly examine the relationship between economic growth and WEF footprint by investigating the existence of an Environmental Kuznets Curve (EKC). GLS regression and the LOWESS model are used to explore the economic growth and WEF footprint nexus in the eight economic zones and the three regions of China. The results indicate that besides the traditional EKC shapes, an M-shape exists, and the proportion of the M-shape curve (12.5%) is lower than the traditional EKC (87.5%). The results showed that the LOWESS model may be more conducive to reflect the real relationship between economic growth and WEF footprint. According to the analysis, the policy suggestions are put forward to promote the sustainable development of the water-energy-food system. In addition, the study can provide some ideas for solving the contradiction of land use. HIGHLIGHTS Using ecological footprint measurement to study water-energy-food system.; EKC hypothesis is used to investigate the relationship between the WEF footprint and economic growth, and policy suggestions are further put forward.; LOWESS model and GLS regression are both introduced to test the EKC hypothesis.;
Показать больше [+] Меньше [-]Development of a Molecular Marker Based on the Mitochondrial Genome for Detection of Cyclospora cayetanensis in Food and Water Samples Полный текст
2022
Durigan, Mauricio | Patregnani, Emma | Gopinath, Gopal R. | Ewing-Peeples, Laura | Lee, Chaeyoon | Murphy, Helen R. | Almeria, Sonia | Cinar, Hediye Nese | Negrete, Flavia | da Silva, Alexandre J.
Cyclospora cayetanensis is a coccidian parasite that causes diarrheal illness outbreaks worldwide. The development of new laboratory methods for detection of C. cayetanensis is of critical importance because of the high potential for environmental samples to be contaminated with a myriad of microorganisms, adversely impacting the specificity when testing samples from various sources using a single molecular assay. In this study, a new sequencing-based method was designed targeting a specific fragment of C. cayetanensis cytochrome oxidase gene and developed as a complementary method to the TaqMan qPCR present in the U.S. FDA BAM Chapter 19b and Chapter 19c. The comparative results between the new PCR protocol and the qPCR for detection of C. cayetanensis in food and water samples provided similar results in both matrices with the same seeding level. The target region and primers in the protocol discussed in this study contain sufficient Cyclospora-specific sequence fidelity as observed by sequence comparison with other Eimeriidae species. The sequence of the PCR product appears to represent a robust target for identifying C. cayetanensis on samples from different sources. Such a sensitive method for detection of C. cayetanensis would add to the target repertoire of qPCR-based screening strategies for food and water samples.
Показать больше [+] Меньше [-]Environmental assessment of vegetable crops towards the water-energy-food nexus: A combination of precision agriculture and life cycle assessment Полный текст
2022
Del Borghi, Adriana | Tacchino, Valeria | Moreschi, Luca | Matarazzo, Agata | Gallo, Michela | Arellano Vazquez, Diego
The increase in world population and the resulting demand for food, water and energy are exerting increasing pressure on soil, water resources and ecosystems. Identification of tools to minimise the related environmental impacts within the food–energy–water nexus is, therefore, crucial. The purpose of the study is to carry out an analysis of the agri-food sector in order to improve the energy-environmental performance of four vegetable crops (beans, peas, sweet corn, tomato) through a combination of precision agriculture (PA) and life cycle assessment (LCA). Thus, PA strategies were identified and a full LCA was performed on actual and future scenarios for all crops in order to evaluate the benefits of a potential combination of these two tools. In the case study analysed, a life cycle approach was able to target water consumption as a key parameter for the reduced water availability of future climate scenarios and to set a multi-objective function combining also such environmental aspects to the original goal of yield maximisation. As a result, the combination of PA with the LCA perspective potentially allowed the path for an optimal trade-off of all the parameters involved and an overall reduction of the expected environmental impacts in future climate scenarios.
Показать больше [+] Меньше [-]Screening of Raw and Modified Biochars from Food Processing Wastes for the Removal of Phosphates, Nitrates, and Ammonia from Water Полный текст
2022
Styliani E. Biliani | John Vakros | Ioannis D. Manariotis
The aim of this work was to compare the performance of biochar from various food processing wastes of different origin for the removal of different nutrients from water. Eggshells (EGS), rice husk (RH), and coffee biochars were pyrolyzed at 400 and 800 °:C and were examined for the removal of phosphates, nitrates, and ammonia nitrogen. The raw materials were also modified with magnesium chloride in order to investigate their sorption behavior. The highest sorption capacity (qmax) for phosphates and ammonium was observed with EGS pyrolyzed at 800 °:C and was 11.45 mg PO43&minus:-P/g and 11.59 mg NH3-N/g, while the highest nitrates sorption capacity was observed with the magnesium-modified RH pyrolyzed at 800 °:C (5.24 mg NO3&minus:-N). The modified EGS biochars pyrolyzed at 800 °:C had almost the half the sorption capacity for phosphates and nitrates compared to the unmodified materials. The modification of RH pyrolyzed at 800 °:C resulted in higher sorption capacity by 34 and 158% for phosphates and ammonium, respectively. The coffee raw and modified biochars were less efficient in nutrient removal compared to the other materials. The specific surface area values of the biochars examined is not a decisive factor for nutrient sorption. The reaction between magnesium and calcium (for the eggshell samples) ions with phosphates is responsible for the higher sorption efficiency. On the other hand, the presence of magnesium and calcium ions has a detrimental effect on the sorption of NH3-N.
Показать больше [+] Меньше [-]GIS-based assessment for the potential of implementation of food-energy-water systems on building rooftops at the urban level Полный текст
2022
Montealegre, A.L. | García-Pérez, S. | Guillén-Lambea, S. | Monzón-Chavarrías, M. | Sierra-Pérez, J.
This research develops a bottom-up procedure to assess the potential of food-energy-water (FEW) systems on the rooftops of buildings in an urban district in Spain considering the urban morphology of the built environment and obtains accurate assessments of production and developmental patterns. A multicriteria decision-making technique implemented in a geographical information system (GIS) environment was used to extract suitable rooftop areas. To implement this method, the slope (tilt), aspect (azimuth), shading, and solar radiation of the rooftops were calculated using LiDAR (Light Detection and Ranging) data and building footprints. The potential of FEW system implementation was analysed at the building and morphology levels. The results showed several differences between residential and non-residential urban morphologies. Industrial areas contained the highest productivity for FEW systems. The production was 2.51 kg of tomatoes/m², 48 kWh of photovoltaic energy/m², and 0.16 l of rainwater/m². Regarding the residential urban morphologies, the more compact tents resulted in better performance. Among the FEW systems, although water could best benefit from the features of the entire roof surface, the best production results were achieved by energy. The food system is less efficient in the built environment since it requires flat roofs. The methodology presented can be applied in any city, and it is considered optimal in the European context for the development of self-production strategies for urban environments.
Показать больше [+] Меньше [-]Effects of urban demand for food and water on physicochemicals and biotic structure of riverine wetlands in the Pampean plain Полный текст
2022
Gómez, Nora | Siri, Augusto | Capítulo, Leandro Rodrigues | Colautti, Darío César | Alcalde, Leandro | Rodrigues Capítulo, Alberto | Donato, Mariano | Fernanda Álvarez, María | de Souza, Javier Ricardo García | Jensen, Roberto Francisco | Bauer, Delia Elena | Maroñas, Miriam | Paredes del Puerto, Juan Martín | Altieri, Paula | Armendáriz, Laura Cecilia | Benitez, Hernán Hugo | Cassano, María Julia | Cortese, Bianca | Di Giorgi, Hugo Daniel | Donadelli, Jorge Luis | Gelis, María Mercedes Nicolosi | García, Ignacio Daniel | Maiztegui, Tomás | Paracampo, Ariel Hernán | Sánchez, Rocío María | Sathicq, María Belén | Catanzaro, Ludmila Noelia Soledad Rodríguez
Riparian areas of riverine plains develop extensive floodable areas named riverine wetlands, which are essential to the water cycle balance and ecosystem dynamics. In this study, we contrasted the hydrological and physicochemical variables of riverine wetlands of both peri-urban areas impacted by intensive farming and those of rural areas with the indicators of the biotic structure (taxonomic richness, Shannon diversity and total density) of benthic diatoms, phytoplankton, zooplankton, macroinvertebrates, chironomids, fishes, turtles, and birds. The study was performed on riverine waters of the Pampean plain, Argentina, with four seasonal samplings conducted in 2017–2018. Our results showed that the significant deepening of the groundwater level caused by aquifer overexploitation in peri-urban areas, as well as the declining surface water quality with higher phosphorus and total nitrogen concentrations, affected the taxonomic richness, diversity, and total density of the biotic assemblages of riverine wetlands. The taxonomic richness of birds, turtles, phytoplankton, chironomids, and fishes was the most sensitive to land use. Phytoplankton, chironomid, and fish diversity showed the greatest differences between rural and peri-urban riverine waters, while the total density of chironomids and birds showed the greatest differences according to land use. The results suggest that the socioeconomic development in those riverine wetlands that still maintain conditions close to the natural ones needs to be subject to guidelines derived from integrated basin management and sustainable urban planning.
Показать больше [+] Меньше [-]Secular trends and customer characteristics of sweetened beverage and water purchasing at US convenience and other small food stores, 2014–2017 Полный текст
2022
Winkler, Megan R. | Lenk, Kathleen | Erickson, Darin | Laska, Melissa N.
BACKGROUND: Cardiovascular health is linked to sugar- and artificially-sweetened beverages (SSBs and ASBs). Prior studies document declines in SSB purchases. However, it is unclear if similar trends exist at convenience and other small food outlets, which often serve lower-income communities and where objective point-of-sales data are difficult to obtain. We examined trends (2014–2017) in observed SSB, ASB, and water purchases at convenience and other small stores as well as differences in purchasing by customer characteristics. METHODS: We used observational purchase data collected annually (2014–2017) from 3010 adult customers at 147 randomly-sampled stores in Minneapolis/St. Paul, USA. SSB sub-types included any ready-to-drink sweetened soda, fruit, sport, energy, tea, or other drink, and ASBs included artificially-sweetened versions. Unsweetened water included ready-to-drink water. Mixed regression models examined trends over time and associations with customer characteristics, accounting for customers nested within stores and stores repeatedly measured over time. RESULTS: Nearly 50% of purchases included an SSB. Approximately 10% included an ASB. There was no evidence of change over time in SSB or ASB purchasing. Customer purchasing of unsweetened water significantly increased over time (5.7 to 8.4%; P for trend = 0.05). SSB purchasing was highest among men, young adults, customers with lower education/ income, and customers that shopped frequently. ASB purchasing was highest among women, those 40–59 years, non-Hispanic White, Hispanic, and customers with higher education/ income. CONCLUSIONS: Despite research suggesting previous declines in SSB consumption and purchasing in the US, we identified a persistent, high trend of SSB purchasing overtime at convenience and other small food stores. Consumption of SSBs and water are growing targets for public policy and health campaigns. Results demonstrate additional work is needed curb sweetened beverage purchasing and promote water purchasing at convenience and other small food stores, which are often prevalent in low-income and marginalized communities.
Показать больше [+] Меньше [-]Co-implementation of precision nutrient management in long-term conservation agriculture-based systems: A step towards sustainable energy-water-food nexus Полный текст
2022
Parihar, C.M. | Meena, B.R. | Nayak, Hari Sankar | Patra, K. | Sena, D.R. | Singh, Raj | Jat, S.L. | Sharma, D.K. | Mahala, D.M. | Patra, S. | Rūpēṣ, | Rathi, N. | Choudhary, M. | Jat, M.L. | Abdallah, Ahmed M.
The conventionally managed cereal-based cropping systems in the Indo-Gangetic Plains (IGP) of South Asia are energy intensive that overwhelm the farm profits and the environmental footprint. This research addresses a complex nexus between yield-energy-water-GHG footprints-economics of conservation agriculture (CA)-based intensified maize-wheat-mungbean rotation. This study evaluated the effect of long-term CA (2012–2020) with optimum nutrient management (2017–20) on energy budgeting, productivity, water and C-footprints, Water productivity (WP), and economics of the CA-based maize-wheat-mungbean system. CA-based permanent bed- and zero tillage flatbed with preceding crop residue retention were compared with the conventional till with preceding crop residue incorporation. These treatments were factored over three-nutrient management alternatives, i.e., GreenSeeker®-guided-N, site-specific nutrient management (SSNM), and recommended fertilizers' dose (Ad-hoc), were compared with farmers' fertilizers practices (FFP). Permanent bed and zero tillage treatments registered higher systems' productivity (18.2 and 12.0%), net returns (44.7 and 34.7%) and water productivity (35.6% and 22.1%), and C-sequestration (54.8 and 62.3%), respectively, over conventional till. Permanent bed- and zero tillage treatments increased the systems' net energy (NE), energy use efficiency (EUE), energy productivity (EP), and energy intensity (EI) by 22.6 and 14.0; 10.1 and 5.6; 9.7 and 5.4; 28.3 and 24.0%, respectively, over conventional till. Conventional till recorded higher net CO₂-eq emission (26.5 and 27.2%), C-footprint (20.8 and 14.5%), and water footprint (27.3 and 18.0%) than permanent bed- and zero tillage treatments. SSNM increased the system's productivity, water productivity, and energy use efficiency, while reducing the system's water- and C-footprints and net CO₂-eq emission. Thus, adopting permanent beds as a crop establishment method with SSNM could be a feasible alternative to attain higher productivity, profitability, and resource use efficiency in the maize-wheat-mungbean system in northwest India.
Показать больше [+] Меньше [-]Onion Essential Oil-in-Water Emulsion as a Food Flavoring Agent: Effect of Environmental Stress on Physical Properties and Antibacterial Activity Полный текст
2022
Elham Taghavi | Afifah Syazwani Abdul Salam | Navideh Anarjan | Elexson Nillian | Mohd Nizam Lani
Plant essential oils (EOs), which are acknowledged as generally recognized as safe (GRAS) by the Food and Drug Administration (FDA), have the potential to be used as a flavoring agent. However, there are limitations to some EOs, such as low water solubility and high volatility, which limit their application in food technology. This study was conducted to develop onion (Allium cepa) EO as a flavoring agent and determine its stability against environmental stress via an emulsification technique, with different concentrations of sodium caseinate, as a delivery system. Emulsions containing onion EO were prepared using different concentrations of sodium caseinate (3, 5, and 7% w/w) via the solvent-displacement technique. The physical properties (average droplet size, color, turbidity, and stability measurement) and antibacterial activity (agar disk diffusion method) of emulsions were then determined. Results show that emulsion with 7% (w/w) sodium caseinate was the most desirable sample in terms of physical properties and antibacterial activity. Hence, it was selected for environmental stress studies (i.e., thermal processing, freeze-thaw cycles, and ultraviolet (UV) exposure). Results revealed that all types of environmental stresses had significant (p<0.05) effects on droplet size, color, turbidity, and stability. Generally, the environmental stresses increased the droplet size except in the freeze-thaw cycle case, while all stresses decreased the stability and lightness. All types of environmental stress treatment did not show a significant (p<0.05) effect on antibacterial activity enhancement against Salmonella Typhimurium and Listeria monocytogenes except in the case of UV treatment against L. monocytogenes. Therefore, the present work has demonstrated the potential use of emulsion as an encapsulation and delivery system of EO flavors for food applications.
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