The Model of Emissions of Gases and Aerosols from Nature (MEGANv2.1) together with the Modern-Era Retrospective Analysis for Research and Applications (MERRA) meteorological fields were used to ...create a global emission data set of biogenic volatile organic compounds (BVOC) available on a monthly basis for the time period of 1980–2010. This data set, developed under the Monitoring Atmospheric Composition and Climate project (MACC), is called MEGAN–MACC. The model estimated mean annual total BVOC emission of 760 Tg (C) yr−1 consisting of isoprene (70%), monoterpenes (11%), methanol (6%), acetone (3%), sesquiterpenes (2.5%) and other BVOC species each contributing less than 2%. Several sensitivity model runs were performed to study the impact of different model input and model settings on isoprene estimates and resulted in differences of up to ±17% of the reference isoprene total. A greater impact was observed for a sensitivity run applying parameterization of soil moisture deficit that led to a 50% reduction of isoprene emissions on a global scale, most significantly in specific regions of Africa, South America and Australia. MEGAN–MACC estimates are comparable to results of previous studies. More detailed comparison with other isoprene inventories indicated significant spatial and temporal differences between the data sets especially for Australia, Southeast Asia and South America. MEGAN–MACC estimates of isoprene, α-pinene and group of monoterpenes showed a reasonable agreement with surface flux measurements at sites located in tropical forests in the Amazon and Malaysia. The model was able to capture the seasonal variation of isoprene emissions in the Amazon forest.
Bioremediation is a cost-effective and sustainable approach for treating polluted soils, but our ability to improve on current bioremediation strategies depends on our ability to isolate ...microorganisms from these soils. Although culturing is widely used in bioremediation research and applications, it is unknown whether the composition of cultured isolates closely mirrors the indigenous microbial community from contaminated soils. To assess this, we paired culture-independent (454-pyrosequencing of total soil DNA) with culture-dependent (isolation using seven different growth media) techniques to analyse the bacterial and fungal communities from hydrocarbon-contaminated soils. Although bacterial and fungal rarefaction curves were saturated for both methods, only 2.4% and 8.2% of the bacterial and fungal OTUs, respectively, were shared between datasets. Isolated taxa increased the total recovered species richness by only 2% for bacteria and 5% for fungi. Interestingly, none of the bacteria that we isolated were representative of the major bacterial OTUs recovered by 454-pyrosequencing. Isolation of fungi was moderately more effective at capturing the dominant OTUs observed by culture-independent analysis, as 3 of 31 cultured fungal strains ranked among the 20 most abundant fungal OTUs in the 454-pyrosequencing dataset. This study is one of the most comprehensive comparisons of microbial communities from hydrocarbon-contaminated soils using both isolation and high-throughput sequencing methods.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Soy protein isolate (SPI) based films, blended with gelatin and plasticized with glycerol at pH 10, were prepared by compression molding with the aim to obtain environmentally friendly materials for ...packaging applications. Different contents and types of gelatin were incorporated into SPI-based mixtures to improve mechanical properties. All films obtained were flexible and transparent. Films with 15% of bovine gelatin showed higher tensile strength and similar elongation at break compared with the ones without gelatin. Moreover, contact angle measurements showed that the addition of gelatin decreased the hidrophilicity of the films, while UV barrier properties were maintained. The effect of gelatin addition has been explained using Fourier transform infrared (FTIR) and the changes observed in the intensity of the bands corresponding to the amide group showed that gelatin interacts with SPI, which was confirmed by the decrease of total soluble matter.
Soil microbiome modification may alter system function, which may enhance processes like bioremediation. In this study, we filled microcosms with gamma-irradiated soil that was reinoculated with the ...initial soil or cultivated bacterial subsets obtained on regular media (REG-M) or media containing crude oil (CO-M). We allowed 8 weeks for microbiome stabilization, added crude oil and monoammonium phosphate, incubated the microcosms for another 6 weeks, and then measured the biodegradation of crude oil components, bacterial taxonomy, and functional gene composition. We hypothesized that the biodegradation of targeted crude oil components would be enhanced by limiting the microbial taxa competing for resources and by specifically selecting bacteria involved in crude oil biodegradation (i.e., CO-M). Postincubation, large differences in taxonomy and functional gene composition between the three microbiome types remained, indicating that purposeful soil microbiome structuring is feasible. Although phylum-level bacterial taxonomy was constrained, operational taxonomic unit composition varied between microbiome types. Contrary to our hypothesis, the biodegradation of C10 to C50 hydrocarbons was highest when the original microbiome was reinoculated, despite a higher relative abundance of alkane hydroxylase genes in the CO-M microbiomes and of carbon-processing genes in the REG-M microbiomes. Despite increases in the relative abundances of genes potentially linked to hydrocarbon processing in cultivated subsets of the microbiome, reinoculation of the initial microbiome led to maximum biodegradation.
In this study, we show that it is possible to sustainably modify microbial assemblages in soil. This has implications for biotechnology, as modification of gut microbial assemblages has led to improved treatments for diseases like Clostridium difficile infection. Although the soil environment determined which major phylogenetic groups of bacteria would dominate the assemblage, we saw differences at lower levels of taxonomy and in functional gene composition (e.g., genes related to hydrocarbon degradation). Further studies are needed to determine the success of such an approach in nonsterile environments. Although the biodegradation of certain crude oil fractions was still the highest when we inoculated with the diverse initial microbiome, the possibility of discovering and establishing microbiomes that are more efficient in crude oil degradation is not precluded.
Thermosetting resins were synthesized by the partial replacement of the synthetic epoxy prepolymer based on diglycidyl ether of bisphenol A (DGEBA) with increasing amounts of epoxidized soybean oil ...(ESO) with methyltetrahydrophthalic anhydride as a crosslinking agent and 1-methyl imidazole as an initiator. Calorimetric studies showed a drop in the reaction heat with ESO content; this was associated with the lower reactivity of oxirane rings in ESO due to steric constrains. The effects of the replacement of increasing amounts of synthetic DGEBA with ESO on the network properties, such as the storage modulus (E′) in the glassy and rubbery regions, glass-transition temperature (Tg), and impact and compressive properties were examined. All formulations were transparent, although phase-separated morphologies were evidenced by scanning electron microscopy observations. The intensity of the transmitted light passed to a minimum at a short reaction time associated with the cloud point and then increased continuously until the refractive index of the dispersed phase approximated that of the continuous phase at complete conversion. The combination of DGEBA with 40 wt % ESO resulted in a resin with an optimum set of properties; E′ in the glassy state was 93% of that of the neat DGEBA resin, Tg decreased only about 11°C, and the impact strength increased about 38% without a loss of transparency.
Phytoremediation is a potentially inexpensive alternative to chemical treatment of hydrocarbon-contaminated soils, but its success depends heavily on identifying factors that govern the success of ...root-associated microorganisms involved in hydrocarbon degradation and plant growth stimulation. Arbuscular mycorrhizal fungi (AMF) form symbioses with many terrestrial plants, and are known to stimulate plant growth, although both species identity and the environment influence this relationship. Although AMF are suspected to play a role in plant adaptation to hydrocarbon contamination, their distribution in hydrocarbon-contaminated soils is not well known. In this study, we examined how AMF communities were structured within the rhizosphere of 11 introduced willow cultivars as well as unplanted controls across uncontaminated and hydrocarbon-contaminated soils at the site of a former petrochemical plant. We obtained 69 282 AMF-specific 18S rDNA sequences using 454-pyrosequencing, representing 27 OTUs. Contaminant concentration was the major influence on AMF community structure, with different AMF families dominating at each contaminant level. The most abundant operational taxonomic unit in each sample represented a large proportion of the total community, and this proportion was positively associated with increasing contamination, and seemingly, by planting as well. The most contaminated soils were dominated by three phylotypes closely related to Rhizophagus irregularis, while these OTUs represented only a small proportion of sequences in uncontaminated and moderately contaminated soils. These results suggest that in situ inoculation of AMF strains could be an important component of phytoremediation treatments, but that strains should be selected from the narrow group that is both adapted to contaminant toxicity and able to compete with indigenous AMF species.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Rhizophagus irregularis
(previously named
Glomus irregulare
) is one of the most widespread and common arbuscular mycorrhizal fungal (AMF) species. It has been recovered worldwide in agricultural and ...natural soils, and the isolate DAOM-197198 has been utilized as a commercial inoculant for two decades. Despite the ecological and economical importance of this taxon, specific markers for quantification of propagules by quantitative real-time PCR (qPCR) are extremely limited and none have been rigorously validated for quality control of manufactured products such as biofertilizers. From the sequencing of 14 complete AMF mitochondrial (mt) genomes, a qPCR assay using a hydrolysis probe designed in the single copy
cox3-rnl
intergenic region was tested and validated to specifically and accurately quantify the spores of
R. irregularis
isolate DAOM-197198. Specificity tests were performed using standard PCR and qPCR, and results clearly showed that the primers specifically amplified the isolate DAOM-197198, yielding a PCR product of 106 bp. According to the qPCR analyses on spores produced in vitro, the average copy number of mt genomes per spore was 3172 ± 304 SE (
n
= 6). Quantification assays were successfully undertaken on known and unknown samples in liquid suspensions and commercial dry formulations to show the accuracy, precision, robustness, and reproducibility of the qPCR assay. This study provides a powerful molecular toolkit specifically designed to quantify spores of the model AMF isolate DAOM-197198. The approach of molecular toolkit used in our study could be applied to other AMF taxa and will be useful to research institutions and governmental and industrial laboratories running routine quality control of AMF-based products.
The role of resistance training on collagen deposition, the inflammatory profile and muscle weakness in heart failure remains unclear. Therefore, this study evaluated the influence of a resistance ...training program on hemodynamic function, maximum strength gain, collagen deposition and inflammatory profile in chronic heart failure rats. Thirty-two male Wistar rats submitted to myocardial infarction by coronary artery ligation or sham surgery were assigned into four groups: sedentary sham (S-Sham, n = 8); trained sham (T-Sham, n = 8); sedentary chronic heart failure (S-CHF, n = 8) and trained chronic heart failure (T-CHF, n = 8). The maximum strength capacity was evaluated by the one maximum repetition test. Trained groups were submitted to an 8-week resistance training program (4 days/week, 4 sets of 10-12 repetitions/session, at 65% to 75% of one maximum repetition). After 8 weeks of the resistance training program, the T-CHF group showed lower left ventricular end diastolic pressure (P<0.001), higher left ventricular systolic pressure (P<0.05), higher systolic blood pressure (P<0.05), an improvement in the maximal positive derivative of ventricular pressure (P<0.05) and maximal negative derivative of ventricular pressure (P<0.05) when compared to the S-CHF group; no differences were observed when compared to Sham groups. In addition, resistance training was able to reduce myocardial hypertrophy (P<0.05), left ventricular total collagen volume fraction (P<0.01), IL-6 (P<0.05), and TNF-α/IL-10 ratio (P<0.05), as well as increasing IL-10 (P<0.05) in chronic heart failure rats when compared to the S-CHF group. Eight weeks of resistance training promotes an improvement of cardiac function, strength gain, collagen deposition and inflammatory profile in chronic heart failure rats.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We report the preparation of bone char from bovine bone using CO2 atmosphere at high temperature. Response surface methodology with a central composite rotatable design was applied to optimize the ...process parameters of temperature, time and CO2 flow. The significance and interaction of independent variables were tested by variance analysis and the experimental results showed that temperature and time were the significant factors on BET surface area with an antagonistic effect. The optimum conditions were found to be at temperature of 451 °C, time of 109 min and CO2 flow of 130 cm3 min−1. The bone char obtained from this optimized conditions showed a BET surface area of 137 m2 g−1 and essentially mesoporous structure. This bone char was analyzed by scanning electron microscopy, Fourier transform infrared spectroscopy, pHPZC, X-ray diffraction and thermogravimetric analysis. Batch adsorption studies were performed with Remazol Brilliant Blue R (RBBR). Non-linear fits of Langmuir, Freundlich and Toth isotherm models and pseudo-first-order, pseudo-second-order and Elovich kinetic models to experimental data were investigated. The RBBR adsorption data onto bone char were well described by the Langmuir and Elovich models, indicating a monolayer adsorption (qm = 20.6 mg g−1) on homogenous surface and chemisorption mechanism, respectively. Thermodynamic studies demonstrated that the adsorption process is endothermic and spontaneous.
Display omitted
•Preparation conditions of bone char (BC) under CO2 atmosphere were investigated.•Temperature and time were the significant factors for BET surface area (SBET).•BC optimized (BCop) have SBET of 137 m2 g−1 and hydroxyapatite in its surface.•BCop monolayer adsorption capacity was 20.6 mg g−1 for Remazol Brilliant Blue R.
Breast cancer represents the second most prevalent tumor-related cause of death among women. Although studies have already been published regarding the association between breast tumors and miRNAs, ...this field remains unclear. MicroRNAs (miRNAs) are defined as non-coding RNA molecules, and are known to be involved in cell pathways through the regulation of gene expression. Melatonin can regulate miRNAs and genes related with angiogenesis. This hormone is produced naturally by the pineal gland and presents several antitumor effects. The aim of this study was to understand the action of melatonin in the regulation of miRNA-152-3p in vivo and in vitro.
In order to standardize the melatonin treatment in the MDA-MB-468 cells, we carried out the cell viability assay at different concentrations. PCR Array plates were used to identify the differentiated expression of miRNAs after the treatment with melatonin. The relative quantification of the target gene expression (IGF-IR, HIF-1α and VEGF) was performed by real-time PCR. For the tumor development, MDA-MB-468 cells were implanted in female BALB/c mice, and treated or not treated with melatonin. Moreover, the quantification of the target genes protein expression was performed by immunocytochemistry and immunohistochemistry.
Relative quantification shows that the melatonin treatment increases the gene expression of miR-152-3p and the target genes, and decreased protein levels of the genes both in vitro and in vivo.
Our results confirm the action of melatonin on the miR-152-3p regulation known to be involved in the progression of breast cancer.
PDF
