scholarly journals Cadmium Bioaccumulation in Yellow Foxtail (Setaria glauca L. P. Beauv): Impact on Seed Head Morphology

Author(s):  
D Kosma ◽  
J Long ◽  
S Ebb

Yellow foxtail (Setaria glauca L. P. Beauv) growing on a cadmium-contaminated site was sampled to determine the extent of cadmium bioaccumulation in aerial tissues and the impact of cadmium on growth and development. Water-extractable Cd concentrations in the soil ranged from 5.0 to 18.0 mg L-1. Aerial tissues contained elevated concentrations of Cd (16-48 μg g-1 DW), with mean concentration ratios of >3.0. Since foxtail frequently colonizes disturbed sites, the bioaccumulation of Cd in aerial tissues of foxtail suggests that wildlife feeding upon this plant species could be exposed to elevated Cd levels. A significant negative correlation (r2=0.98) was observed between water-extractable Cd in the soil and seed head length in foxtail, indicative of an adverse effect of Cd on reproductive development. This correlation further suggests seed head length as a biomarker for soluble Cd in contaminated soils. KEYWORDS: Cadmium, bioaccumulation, biomarker, phytotoxicity

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3667
Author(s):  
Claudia Diana Sabău-Popa ◽  
Luminița Rus ◽  
Dana Simona Gherai ◽  
Codruța Mare ◽  
Ioan Gheorghe Țara

In this paper we analyzed the link between companies’ performance, in terms of cash and income, and the labor productivity or management rates, in case of the companies from the energy sector listed on the Bucharest Stock Exchange. We focused on the energy sector because of the impact that its expansion has on the evolution of economies around the world and because of its dynamics in the sense of gradually shifting to the use of energy from renewable sources. We have used panel regression models to analyze the operating cash flow and the profitability rates and the determination of a causal or dependency relationship with labor productivity or management rates. The results of this study show a significant negative correlation between operating cash flows and the average duration of stock rotation, and no correlation between productivity and the operating cash flow. Instead, the average duration of stock turnover does not at all influence the profitability rates, and productivity is always significant for the return on assets, ie forthe return on equitywith a positive coefficient, as expected. The gap between the average duration of payment of suppliers and the average duration of receivables does not significantly influence neither the cash flow nor the rates of return.


2021 ◽  
Vol 11 (14) ◽  
pp. 6451
Author(s):  
Christian E. Hernández-Mendoza ◽  
Pamela García Ramírez ◽  
Omar Chávez Alegría

Soil contamination by different hydrocarbons has rapidly expanded worldwide, surpassing the self-purification capacity of soils and increasing the number of contaminated sites. Although much effort has been devoted to study the effects of diesel contamination on the geotechnical properties of soil, there is still limited available information about it. Moreover, there is no available information about the maximum diesel retention that soil can have and its effect on the geotechnical behavior of the soil. Thus, in this paper, we determined the maximum diesel retention by an unsaturated clayey soil and evaluated the impact of diesel contamination on its geotechnical properties. The results showed that the soil could only retain 12.6% of the added diesel and the excess was expulsed. At such a diesel concentration, the saturation rate of the soil was lower than 80%. Diesel contamination increased the plasticity and the internal friction angle of the soil, while its cohesion was considerably decreased. It should be noted that the matric suction of contaminated soil was lower than the one obtained for natural soil. However, its osmotic suction was considerably higher. This indicates that osmotic suction must be considered to evaluate the shear strength of contaminated soils.


2001 ◽  
Vol 43 (2) ◽  
pp. 291-295 ◽  
Author(s):  
J. Vouillamoz ◽  
M. W. Milke

The effect of compost on phytoremediation of diesel-contaminated soils was investigated using 130 small (200 g) containers in two screening tests. The experiments were conducted in a controlled environment using ryegrass from seed. Containers were destructively sampled at various times and analyzed for plant mass and total petroleum hydrocarbons. The results indicate that the presence of diesel reduces grass growth, and that compost helps reduced the impact of diesel on grass growth. The addition of compost helps increase diesel loss from the soils both with and without grass, though the addition of grass leads to lower diesel levels compared with controls. A second set of experiments indicates that the compost helps in phytoremediation of diesel-contaminated soil independent of the dilution effect that compost addition has. The results indicate that the compost addition allowed diesel loss down to 200 mg TPH/kg even though the compost would be expected to hold the diesel more tightly in the soil/compost mixture. The simplicity of the screening tests led to difficulties in controlling moisture content and germination rates. The conclusion of the research is that the tilling of compost into soils combined with grass seeding appears to be a valuable option for treating petroleum-contaminated soils.


2017 ◽  
Author(s):  
Bin Zhao ◽  
Kuo-Nan Liou ◽  
Yu Gu ◽  
Jonathan H. Jiang ◽  
Qinbin Li ◽  
...  

Abstract. The interactions between aerosols and ice clouds represent one of the largest uncertainties in global radiative forcing from pre-industrial time to the present. In particular, the impact of aerosols on ice crystal effective radius (Rei), which is a key parameter determining ice clouds' net radiative effect, is highly uncertain due to limited and conflicting observational evidence. Here we investigate the effects of aerosols on Rei under different meteorological conditions using 9-year satellite observations. We find that the responses of Rei to aerosol loadings are modulated by water vapor amount in conjunction with several other meteorological parameters. While there is a significant negative correlation between Rei and aerosol loading in moist conditions, consistent with the Twomey effect for liquid clouds, a strong positive correlation between the two occurs in dry conditions. Simulations based on a cloud parcel model suggest that water vapor modulates the relative importance of different ice nucleation modes, leading to the opposite aerosol impacts between moist and dry conditions. When ice clouds are decomposed into those generated from deep convection and formed in-situ, the water vapor modulation remains in effect for both ice cloud types, although the sensitivities of Rei to aerosols differ noticeably between them due to distinct formation mechanisms. The water vapor modulation can largely explain the difference in the responses of Rei to aerosol loadings in various seasons. A proper representation of the water vapor modulation is essential for an accurate estimate of aerosol-cloud radiative forcing produced by ice clouds.


2019 ◽  
Vol 8 (1) ◽  
pp. 82-86
Author(s):  
Anastasia Olegovna Oznobihina

The aim of the study is to conduct biological testing at the initial stages of plant objects viability in the model conditions of heavy metal pollution. The paper presents the results of laboratory experiments to assess the impact of different concentrations of heavy metal salts on the viability of yellow melilot and great trefoil seeds. In the course of the conducted experimental studies the author has been established a direct dependence of the decrease in the indices of germination energy and laboratory germination of seeds with an increase in the concentration of phytotoxicant salts, determined the critical (threshold) concentration of the studied elements and the metal content, in which the processes of growth and development of seeds remain. The concentration of 0,01% cadmium, zinc, lead and copper was optimal for germination of melilot seeds, where germination was equal to 80%, 74%, 69% and 64%, respectively. For great trefoil seeds, high germination rates were noted in case of 0,01% contamination with lead, zinc, cadmium and copper - 82%, 80%, 77% and 76%, respectively, and in 0,1% salt solution of lead, copper and zinc there were recorded 75%, 74% and 72% of seedlings. Zinc in the concentration of 0,01% at the initial stages of germination of phytomeliorant seeds stimulated germination energy. The tendency of resistance to pollution by lead, zinc and copper was observed at sprouts of a great trefoil, and to pollution by cadmium the greatest resistance was shown by a melilot yellow. Defining the limits of the leguminous plant seeds germination in the presence of a toxic agent will allow research and development in respect of biological restoration of contaminated soils and can be used in technologically disturbed lands.


Author(s):  
Saurabh Mahajan ◽  
Ravi Devarakonda ◽  
Gautam Mukherjee ◽  
Nisha Verma ◽  
Kumar Pushkar

Background: Coronaviruses are a family of viruses that can result in different types of illnesses, most commonly, as Severe acute respiratory syndrome (SARS). Researches have shown that the atmospheric variables and the density of population have affected the transmission of the disease. Meteorological variables like temperature, humidity among others have found to affect the rise of pandemic in positive or negative ways.  Respiratory virus illnesses have shown seasonal variability since the time they have been discovered and managed. This study investigated the relationship between the meteorological variables of temperature, humidity and precipitation in the spread of COVID-19 disease in the city of Pune.Methods: This record based descriptive study is conducted after secondary data analysis of number of new cases of COVID-19 per day from the period 01 May to 24 December 2020 in Pune. Meteorological data of maximum (Tmax), minimum (Tmin) and daily average temperature (Tavg), humidity and precipitation were daily noted from Indian meteorological department website. Trend was identified plotting the daily number of clinically diagnosed cases over time period. Pearson’s correlation was used to estimate association between meteorological variables and daily detected fresh cases of COVID-19 disease.  Results: Analysis revealed significant negative correlation (r=-0.3563, p<0.005) between daily detected number of cases and maximum daily temperature. A strong positive correlation was seen between humidity and daily number of cases (r=0.5541, p<0.005).Conclusions: The findings of this study will aid in forecasting epidemics and in preparing for the impact of climate change on the COVID epidemiology through the implementation of public health preventive measures.


Author(s):  
Reza Basiri ◽  
Brent D. Haverstock ◽  
Paul F. Petrasek ◽  
Karim Manji

BACKGROUND: Lower limb amputations (LLAs) are a major debilitating complication of diabetes. The toe and flow model (TFM) describes the framework for multidisciplinary centers aiming to reduce this complication. In this study, we investigate the efficacy of the TFM to reduce diabetes-related major LLAs in comparison with the standard of care (SOC) in the Canadian health care system. METHODS: We retrospectively reviewed the anonymized diabetes-related LLA reports in two similar metropolitan health zones in Alberta, Canada from 2007 to 2017. Although both zones have the same provincial health care system and similar demographics, Calgary, our first zone operates on the basis of the TFM while the Edmonton zone operates in accordance with the provincial SOC. LLAs were divided into minor and major amputation cohorts. We used the chi-square test, linear regression, and Pearson correlation for analysis. The lower proportion of major LLAs was denoted as a positive sign for the efficacy of the TFM. RESULTS: Although the number of LLAs remained relatively comparable (Calgary zone: 2238 and Edmonton zone: 2410), the Calgary zone had both significantly lower major (45%) and higher minor (42%) amputation incidence rates compared to the Edmonton zone. The increasing trend in minor LLAs and decreasing trend in major LLAs in the Calgary zone were negatively and significantly correlated (r = -0.730, p = 0.011). No significant correlation was found in the Edmonton zone. CONCLUSIONS: A significant reduction in the incidence rate, decreasing trend of diabetes-related major LLAs and the significant negative correlation of minor and major LLAs rates in the Calgary zone (TFM) compared to its sister zone Edmonton (SOC), provides supporting evidence for the impact of the TFM. This investigation provides support for a modernization of the diabetes-related limb preservation practice in Canada through the implementation of TFMs across the country to combat major LLAs.


Author(s):  
Jiaping Zhang ◽  
Zhiyong Cai ◽  
Mingwang Cheng ◽  
Huirong Zhang ◽  
Heng Zhang ◽  
...  

A growing body of research has shown that people’s attitudes toward food safety is affected by their availability and accessibility to food risk information. In the digital era, the Internet has become the most important channel for information acquisition. However, empirical evidence related to the impact of Internet use on people’s attitudes towards food safety is inadequate. In this study, by employing the Chinese Social Survey for 2013 and 2015, we have investigated the current situation of food safety perceptions and evaluations among Chinese residents and the association between Internet use and individuals’ food safety evaluations. Empirical results indicate that there is a significant negative correlation between Internet use and people’s food safety evaluation in China. Furthermore, heterogeneity analysis shows that Internet use has a stronger negative correlation with food safety evaluation for those lacking rational judgment regarding Internet information. Specifically, the negative correlation between Internet use and food safety evaluations is more obvious among rural residents, young people, and less educated residents. Finally, propensity score matching (PSM) is applied to conduct a robustness check. This paper provides new evidence for studies on the relationship between Internet use and an individuals’ food safety cognition, as well as additional policy enlightenment for food safety risk management in the digital age.


Inventions ◽  
2020 ◽  
Vol 5 (3) ◽  
pp. 43
Author(s):  
Karuna Arjoon ◽  
James G. Speight

Crude oil is the world’s leading fuel source and is the lifeblood of the industrialized nations as it is vital to produce many everyday essentials. This dependency on fossil fuels has resulted in serious environmental issues in recent times. Petroleum contaminated soils must be treated to ensure that human health and the environment remain protected. The restoration of petroleum-polluted soil is a complex project because once petroleum hydrocarbon enters the environment, the individual constituents will partition to various environmental compartments in accordance with their own physical–chemical properties; therefore, the composition and inherent biodegradability of the petroleum hydrocarbon pollutant determines the suitability of a remediation approach. The objective of this study was to assess the prospective of bioremediation as a feasible technique for practical application to the treatment of petroleum hydrocarbon-contaminated soils, by trending the changes in the properties of the petroleum due to biodegradation. Each polluted soil has particularities, thus, the bioremediation approach for each contaminated site is unique. Therefore, hydrocarbon-contaminated sites that have remained polluted for decades due to lack of proper decontamination treatments present in this part of the world would benefit from cost effective treatments. Most bioremediation case studies are usually based on hypothetical assumptions rather than technical or experimental data; providing data that show the capabilities of biodegradation of indigenous microbes on specific oil composition can lead to the creation of strategies to accelerate the biological breakdown of hydrocarbons in soil.


Author(s):  
W. Blommaert ◽  
K. Mannaerts ◽  
S. Pepin ◽  
B. Dehandschutter

Like in many countries, polluted industrial sites also exist in Belgium. Although the contamination is purely chemical in most cases, they may also contain a radioactive component. For chemically contaminated sites, extensive regulations and methodologies were already developed and applied by the different regional authorities. However and essentially because radioactivity is a federal competence, there was also a necessity for developing a legal federal framework (including an ER-methodology [1]) for remediation of radioactive contaminated sites. Most of the so-called radioactive contaminated sites are exhibiting a mixed contamination (chemical and radiological), and hence the development of such methodology had to be in line with the existing (regional) ones concerning chemical contamination. Each authority having their own responsibilities with regard to the type of contamination, this makes it more complicated and time-consuming finding the best solution satisfying all involved parties. To overcome these difficulties the legal framework and methodology — including the necessary involvement of the stakeholders and delineation of each party’s responsibilities — has to be transparent, clear and unambiguous. Once the methodology is developed as such and approved, the application of it is expected to be more or less easy, logic and straightforward. But is this really true? The aim of this document is to investigate as well the impact of factors such as the type of radioactive contamination — levels of contamination, related to NORM activity or not, homogeneous or heterogeneous, the differences in licensing procedures,… — on the application of the developed methodology and what could be the consequences in the long run on the remediation process. Two existing case studies in Belgium will be presented ([2]). The first case deals with a historical radium contaminated site, the second one with a phosphate processing facility still in operation, both with (very) low levels of radioactivity but containing very large volumes of contaminated materials. These case studies will demonstrate that, although the applied methodology will be the same in both cases, the impact of e.g. sampling strategy, scenario definitions, modelisations, final destination of the land, presence of chemotoxic components, dose or risk assessments, uncertainties, derivation of clean-up radionuclide guidelines, stakeholder involvement and waste treatment could be important on licensing, cost-estimate, planning and final outcome of the environmental remediation activities to be executed.


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