Identification of stress and Ca metabolism related gene expression in wild Peromyscus exposed to environmental lead | Author : Amit Basu | Abstract | Full Text | Abstract :Identification of stress and Ca metabolism related gene expression in wild Peromyscus exposed to environmental lead |
| Modeling a HPGe detectors absolute efficiency as a function of gamma energy and soil density in uncontaminated soil | Author : Maurice O. Miller | Abstract | Full Text | Abstract :This study develops a mathematical model for predicting the absolute efficiency value of a HPGe detector based on the gamma energy and soil density for a typical counting arrangement for measuring gamma activity concentration in uncontaminated surface soils. The generation of the experimental efficiency curves was carried in AGLE 3.0 using the Ortec GEM-FX8530P4 with a warranted resolution (FWHM) at 1.33 MeV (Co-60) =1.9 keV and factory reported measured value of 1.76 keV. ANGLE 3.0 was used to output the efficiency and solid angle data for the various soil densities in the density range 0.8 – 1.8 g cm-3 and gamma range 20 – 2000 keV. The inter-relationship is defined using SigmaPlot, as a 3D Lorentzian model with R2= 0.9925. Further analysis was done to determine the uncertainties in this predictive model, and a set of correcting equations based on energy ranges were developed. The data indicated that with each soil density, the uncertainties increase with increasing gamma energy in the energy range 400 – 1600 keV, and that the level of uncertainty was significant. The uncertainties at the energy range below 400 keV were not considered significant within the context of general experimental errors.
Keywords: detector characterization, semi-empirical, ANGLE, uncertainties, HPGe, detector efficiency |
| Triphenyl phosphate (TPP) and tris (2-chloroisopropyl) phosphate (TCPP) induced apoptosis and cell cycle arrest in HepG2 cells | Author : Jing An | Abstract | Full Text | Abstract :The purpose of this study was to investigate the effects of organophosphate flame retardants (OPFRs) exposure in human liver carcinoma cell line HepG2 in terms of cell viability, apoptosis induction and cell cycle changes. The results data showed that triphenyl phosphate (TPP) and tris (2-chloroisopropyl) phosphate (TCPP) could significantly inhibit the cell proliferation and enhance the level of reactive oxygen species (ROS) and mitochondrial membrane potential (MMP). Moreover, TPP reduced the activities of c-Jun N-terminal kinase (JNK), extracellular regulated protein kinases (ERK1/2) and p38 pathways, while TCPP activated the p38 pathway in HepG2 cells. In addition, TPP mainly induced apoptosis by activating p53-regulated apoptotic pathway, whereas TCPP activated both mitochondrial and p53-mediated apoptosis pathway in HepG2 cells. Furthermore, by regulating the expression of cell cycle proteins, TPP induced cell cycle arrest at G1 and S phase; while TCPP mainly lead to cell cycle arrest at G1-phase. Taken together, the toxicity of TPP and TCPP in the HepG2 cells is associated with ROS generation and MMP alterations, which could induce apoptosis and cell cycle arrest through different molecular pathways. The more severe cytotoxicity of TPP than TCPP might relate to the benzene rings structure of TPP.
Keywords: TPP; TCPP; oxidative stress; apoptosis; cell cycle arrest |
| Formulation of culture media using fish scale bioconversion | Author : Aline Simões da Rocha Bispo | Abstract | Full Text | Abstract :The biodegradation of fish scale residues is an alternative method to convert crude proteins into bioproducts of industrial interest. In view of this panorama, the objective of this study was to evaluate the use of tilapia scales as a supplement for the growth of Bacillus subtilis. For this, the work was divided into two stages. In stage 1, degradation assays with Bacillus isolates (B1, B2, and B3) were carried out in minimal mineral medium (MMM), supplemented with 1 g of fish scales, to which 1 mL of inoculum (108 UFC mL-1) was added. The culture was incubated for six days at 125 rpm and 37 °C, and the pH was measured at the end of the degradation. In stage 2, two scale-based culture media (broths C1 and C2) were formulated. The efficiency of the formulated media was determined by the specific growth rate µ (h-1) and the doubling time td (h) of B. subtilis (B1). Isolate B1 presented with the highest degradation yield from the treatment with the crushed scales and with a higher increase in the pH value (7.8) in the medium. In broth C1, the B. subtilis microorganism (B1) had a higher specific growth rate (1.9363 h-1) and a shorter replication time (21.5 min). Therefore, different species of Bacillus were able to degrade the tilapia scales, and this product was found to be efficient in the formulation of culture media. This work demonstrates the application of novel technologies for the use of agroindustrial residues from the fish industry, resulting in a financial gain for the industry itself.
Keywords: agroindustrial residues, Bacillus subtilis, generation time, microbial growth |
| Exploiting low-cost and commonly shared aerial photographs and LiDAR data for detailed vegetation structure mapping of the Wadden Sea island of Ameland | Author : Mücher, C.A | Abstract | Full Text | Abstract :Regular mapping of vegetation structure is important for biodiversity monitoring, and increasingly for tracking compliance with nature policy mandates. As such, the Netherlands uses vegetation structure mapping to monitor the Natura 2000 site on the Dutch Wadden Sea island of Ameland. Three decades of natural gas extraction here has caused soil subsidence, impacting vegetation and habitats on the island. In the Netherlands, vegetation structure mapping is typically done using conventional techniques, primarily field surveys combined with visual interpretation of aerial photographs. This procedure is time-consuming and often too inconsistent and inefficient for large areas. In the current study we exploited commonly shared and low-cost aerial photographs and LiDAR data for detailed vegetation structure mapping. Aerial photographs are not always easy to use in automatic classification procedures, as they often lack calibrated spectral reflectance values. Furthermore, pre-processing of aerial photographs to render them more attractive may skew the image so that it no longer accurately depicts the original scene anymore. Our aim was to determine if automatic or semi-automatic classification techniques could be applied to these readily available Dutch data to support mapping and monitoring of the vegetation structure of larger areas. We compared the effectiveness of two well-known classification methods, namely rule-based (RB) and random forest (RF). The RF algorithm was applied with its default settings, as supplied by eCognition software. Both classification methods performed well, with overall accuracies of 84.1% (RB) and 86.4% (RF). Each method, however, has its advantages and disadvantages, which are discussed. Overall, RF classification was preferred over RB classification, as it was better able to handle the complexity of the rules needed for distinguishing more classes. Provision of in situ training data, such as vegetation relevés, was not really problem in the Dutch context. Nevertheless, exploitation of new digital aerial photographs produced each year in a semi-automatic process remains a challenge. Commercial high resolution satellite imagery (~0.5 m resolution) is therefore still preferred by us. This latter, unfortunately, is more costly than aerial photographs which, while not always ideal, are readily available at no additional costs for involved organisations. |
| WATER SUPPLY AND ACCESS TO SAFE WATER IN DEVELOPING ARID COUNTRIES | Author : TeresaValente | Abstract | Full Text | Abstract :The supply of drinking water is one of the major concerns in semi-arid and arid climates, mainly in developing countries. The present study reviews the situation of the water supply in a West African coast country, the archipelago of Cape Verde, with focus on the most populous island (Santiago), regarding the rate of public coverage and the water quality.
As main insights, the research indicates that at Santiago Island only 54% of the population has connection to the public network, while 24% uses wells, springs and other potentially non-potable sources. The region of São Domingo’s is one of the most critical, with only 6.5% of public supply, justifying the assessment of the water quality used by this population. With regard to water quality, the results of this study indicate that natural and anthropic factors are contributing to degradation of the water resources, with salinity, chloride, nitrates, and nitrites as major concerning pollutants. The insufficiency of the public supply in this island could be a reflection of the situation in other arid regions of Africa. Though the recent advances it is vital to continue or even increase with the international cooperation to provide for adequate water supply infrastructures.
Keywords: public water supply, coverage rate, water points, scarcity, quality, Santiago Island |
| Effects of landscape on the distributions of nutrients and polycyclic aromatic hydrocarbons in an urban river system | Author : Hai-Liang Zhu | Abstract | Full Text | Abstract :Urban river systems have large potentials for determining the fate, distribution, and transport of water contaminants. This study was conducted to investigate the distribution and identify the sources of 16 Environmental Protection Agency priority polycyclic aromatic hydrocarbons with respect to four different urban river landscapes (river channels managed with hard revetment, unmanaged, with wetland construction, and in city park). The significant differences of water nutrient physicochemical indices in the four landscapes were also compared with the general linear model, and their relationship with polycyclic aromatic hydrocarbons were analyzed using principal component analysis. The results showed that the city parks and wetlands may improve the water quality and accelerate degradation of contaminants. Furthermore, the river channels in the park and wetland had lowered proportions of low molecular weight (2, 3-rings) polycyclic aromatic hydrocarbons in the river sediment compared to urban river channels with other two landscapes.
Key words: Jialu River, Polycyclic aromatic hydrocarbons, Wetland, City park |
| The influence of annual variation and seasonal turnover of plant communities in hybrid ecosystems on metrics of biodiversity: implications for herbaceous vegetation sampling design | Author : Ashlee Nichter | Abstract | Full Text | Abstract :Background : Most researchers recognize and account for annual and seasonal turnover of herbaceous vegetation in sampling protocols, but few have evaluated and quantified these effects and even fewer have evaluated these effects in hybrid ecosystems. We analyzed annual and seasonal turnover in herbaceous vegetation diversity in grassland reserves, ditches, and field margins in northwest, Ohio.
Methods : We sampled 33 sites in 2016 and 61 sites in 2017 with 21 sites sampled in both years. The point-intercept method was used to identify species presence along either side of two 10 meter transects. Site similarity was characterized using the Jaccard similarity index. Annual variation was analyzed via a z-test, to test the difference of similarity from complete similarity. Seasonal variation was analyzed using repeated measures ANOVA.
Results : We identified 139 species in 2016 (54% native and 46% nonnative) and 154 species in 2017 (57% native and 43% nonnative). We identified 93 species (52% native and 48% nonnative) both in 2016 and in 2017. We found a significant difference in annual site similarity (P < 0.01), and a significant difference in seasonal turnover in 2016 and 2017 between all sampling periods (P < 0.01), except Spring to Summer versus Summer to Fall in 2016 (P = 0.19).
Conclusion: Because there is annual and seasonal turnover in species composition, sampling herbaceous vegetation should occur across multi-years and during multi-seasonal sampling bouts to characterize diversity in an ecosystem. Highest diversity levels occurred during the summer (June to July) and could be used to maximize sampling efficiency.
Keywords: Annual turnover, Hybrid ecosystems, Jaccard similarity index, Novel ecosystems, Seasonal turnover |
| HEAVY METALS CONCENTRATION AND POLLUTION ASSESSMENT OF THE BEACH SEDIMENTS IN LAGOS, SOUTHWESTERN NIGERIA | Author : Ayodele Olusiji Samuel | Abstract | Full Text | Abstract :Beach sediment samples were randomly collected as surface samples along Lagos and Badagry axis at a depth of 40cm for heavy metals analysis. Eight heavy metals such as Fe, Pb, Cu, Ni, Co, Zn, Mn and Cd were analyzed using the Atomic Absorption Spectrophotometer and the analyses revealed that Fe has values ranging from 4344.66 to 9154.86 ppm followed by Pb between 133.39 and 778.08 ppm respectively. Ni content ranges from 2.12-4.61 ppm, Zn (11.13-18.79 ppm); Mn (38.32-68.45 ppm) and Cu (18.03-21.35 ppm). Co and Cd content are extremely low and almost negligible in all locations. The average Enrichment Factor values indicates that Pb has extremely high enrichment, Cu has very high enrichment, Fe and Zn has significant enrichment, Ni and Mn has moderate enrichment, while Co is deficient. Pb is highly enriched in all locations compared to the other heavy metals, which could be as a result of effluent from industrial wastes and biodegradation of materials and seepages from dumpsites into nearby rivers, streams or beaches etc. Also, the contamination factor revealed that all the sediments fell within low contamination factor (CF<1) except Pb, with very high contamination factor. In addition, Fe, Ni, Co, Zn, Mn, Cu and Cd have geo-accumulation indices less than zero indicating no pollution. Values from the modified degree of contamination classified the sample sites as having moderate degree of contamination. All the Pollution Load Index values are less than 0.5, implying that there is no need for drastic rectification measures to be taken at the sites investigated. Ni, Co, Zn, Mn, Cu and Cd showed low ecological risk at all the locations except for Pb that showed moderate ecological risk. All the metals have potential contamination index values less than 1 (low contamination), except Pb with a value of 39 (severe contamination) which suggested anthropogenic sources.
Keywords: Beach sediments; Heavy metals; Contamination; Anthropogenic source; Enrichment Factor; Geo-accumulation Index |
| Bridging the research-management gap in environmental conservation: A case study from Andalusia, southern Spain | Author : Rodríguez-Rodríguez, D | Abstract | Full Text | Abstract :Science is believed to provide the most objective basis for effective decision-making, though it is rarely implemented in environmental management. Here we reflect on the results of a regional workshop aimed at exploring the knowledge and use of scientific evidence by environmental managers in an ecologically diverse region in southern Spain: Andalusia. Scientists were moderately aware of regional managerial needs. They stated that regional managers’ needs could be mostly addressed by their research centers, and that they often considered managerial needs when conducting research. In turn, environmental managers had limited knowledge of, and interest in, the environmental research carried out in the region. However, managers stated they frequently use scientific outputs in their jobs. The main perceived barriers to effective use of science in regional environmental management by both groups were: different priorities by each group, and limited time of managers to check scientific information. Scientists also perceived that managers were not sufficiently engaged in research and that they were often reluctant to change their usual managerial practices. Managers mentioned inadequate scientific dissemination formats. The perceived solutions to those issues were: reinforcing collaboration mechanisms between both groups; aligning research to managerial needs more closely; greater managers’ awareness of adaptive management; and developing user friendly, synthetic communication tools for managers. The insights from the workshop are intended to help scientists and managers to enhance effective use of environmental science in Spain and elsewhere.
Keywords: Barrier; facilitator; decision-making; science implementation; science impact |
| Influence of nitrogen control on the coupling system of winery wastewater and microalgae cultivation | Author : Wei Wei | Abstract | Full Text | Abstract :This study aimed to research the nutrient uptake by two microalgae at different initial total nitrogen concentrations in winery wastewater, thus laying a theoretical foundation for the future breeding of microalgae with winery wastewater and exploring the nitrogen and phosphorous removal efficiency by using microalgae cultivation technology as well. Six concentrations of total nitrogen (TN) based on winery wastewater were designed. The two species cultured in winery wastewater with proper initial TN (40.25~360 mg/L for Chlamydomonas reinhardtii; 40.25~120 mg/L for Scenedesmus dimorphus) not only grew well, but also achieved outstanding removal efficiencies for TN and total phosphorous (TP). After 17 days cultivation, for Chlamydomonas reinhardtii, Scenedesmus dimorphus and the co-cultured species, the lowest TN removal rate was 71.69%, 72.84% and 70.67% as initial TN was 1100 mg/L respectively; however, the highest TN removal rate for Chlamydomonas reinhardtii reached to 95.15% as initial TN was14 mg/L. For Scenedesmus dimorphus and the co-cultured species, the highest TN removal rates were 98.85% and 99% respectively as initial TN was 5 mg/L. In addition, the regular of TP removal by two algae was entirely distinct and Chlamydomonas reinhardtii was more positive in TP uptake. These results also suggest that different ratio of N/P caused by diverse initial TN concentration could influence largely algal growth and further nutrient removal.
Keywords: Winery wastewater; microalgae; Chlamydomonas reinhardtii; Scenedesmus dimorphus; nitrogen |
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