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Technical approaches to evaluate the surfactant-enhanced biodegradation of biodiesel and vegetable oils.
Montagnolli, RN, Cruz, JM, Moraes, JR, Mendes, CR, Dilarri, G, Lopes, PRM, Bidoia, ED
Environmental monitoring and assessment. 2019;(9):565
Abstract
This research compared the effects of biosurfactant on the biodegradation of biodiesel and vegetable oils while validating two conceptually diverging methodologies. The two experimental setups were successfully modeled towards the effects of biosurfactants during biodegradation. We established the equivalence of both methodologies from the data output. As expected, the biosurfactants caused an increased oil uptake, thus increasing biodegradation performance. Cooking oils were favored by the microbial consortium as a carbon source when compared with biodiesel fuel, especially after use in food preparation. However, we found that biodiesel substrate standout with the highest biodegradation rates. Our results might indicate that a rapid metabolic change from the original compound initially favored biodiesels during the assimilation of organic carbon for a set specialized microbial inoculum. The data output was successfully combined with mathematical models and statistical tools to describe and predict the actual environmental behavior of biodiesel and vegetable oils. The models confirmed and predicted the biodegradation effectiveness with biosurfactants and estimated the required timeframe to achieve satisfactory contaminant removal.
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Associations of Short-Term and Long-Term Exposure to Ambient Air Pollutants With Hypertension: A Systematic Review and Meta-Analysis.
Cai, Y, Zhang, B, Ke, W, Feng, B, Lin, H, Xiao, J, Zeng, W, Li, X, Tao, J, Yang, Z, et al
Hypertension (Dallas, Tex. : 1979). 2016;(1):62-70
Abstract
Hypertension is a major disease of burden worldwide. Previous studies have indicated that air pollution might be a risk factor for hypertension, but the results were controversial. To fill this gap, we performed a meta-analysis of epidemiological studies to investigate the associations of short-term and long-term exposure to ambient air pollutants with hypertension. We searched all of the studies published before September 1, 2015, on the associations of ozone (O3), carbon monoxide (CO), nitrogen oxide (NO2 and NOX), sulfur dioxide (SO2), and particulate matter (PM10 and PM2.5) with hypertension in the English electronic databases. A pooled odds ratio (OR) for hypertension in association with each 10 μg/m(3) increase in air pollutant was calculated by a random-effects model (for studies with significant heterogeneity) or a fixed-effect model (for studies without significant heterogeneity). A total of 17 studies examining the effects of short-term (n=6) and long-term exposure (n=11) to air pollutants were identified. Short-term exposure to SO2 (OR=1.046, 95% confidence interval [CI]: 1.012-1.081), PM2.5 (OR=1.069, 95% CI: 1.003-1.141), and PM10 (OR=1.024, 95% CI: 1.016-1.032) were significantly associated with hypertension. Long-term exposure (a 10 μg/m(3) increase) to NO2 (OR=1.034, 95% CI: 1.005-1.063) and PM10 (OR=1.054, 95% CI: 1.036-1.072) had significant associations with hypertension. Exposure to other ambient air pollutants (short-term exposure to NO2, O3, and CO and long-term exposure to NOx, PM2.5, and SO2) also had positive relationships with hypertension, but lacked statistical significance. Our results suggest that short-term or long-term exposure to some air pollutants may increase the risk of hypertension.
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Effect of environmental exposure to cigarette smoke on blood pressure in 24‑hour ambulatory blood pressure monitoring in patients with essential hypertension.
Gać, P, Poręba, R, Poręba, M, Mazur, G, Sobieszczańska, M
Polskie Archiwum Medycyny Wewnetrznej. 2014;(9):436-42
Abstract
INTRODUCTION A relationship between environmental exposure to cigarette smoke and blood pressure has not been well‑established. OBJECTIVES The aim of the study was to evaluate the effects of environmental exposure to cigarette smoke on blood pressure (BP) in patients with essential hypertension. PATIENTS AND METHODS The study involved 39 nonsmoking patients with essential hypertension treated with hypotensive agents and environmentally exposed to cigarette smoke (group 1) and 39 nonsmoking patients with essential hypertension treated with hypotensive agents and not exposed to cigarette smoke (group 2). The following variables of 24‑hour ambulatory BP monitoring (ABPM) were measured: systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and pulse pressure (PP) during 24‑hour ABPM, and, separately, for the period of daily activity and night rest. RESULTS In group 1, the mean values of 24‑hour SBP, DBP, MAP, and PP, daytime SBP, DBP, MAP, and PP, and nighttime SBP, MAP, and PP were significantly higher than those in group 2. Statistically significant positive linear correlations were demonstrated between the mean time of daily exposure (expressed in hours) to cigarette smoke and 24‑hour MAP and PP (r = 0.52 and r = 0.48, respectively, P <0.05). Advanced age, higher low‑density lipoprotein cholesterol and glucose concentrations, and environmental exposure to cigarette smoke were independent factors of elevated 24‑hour PP in the study group. CONCLUSIONS In patients with essential hypertension, environmental exposure to cigarette smoke may result in elevated BP values in 24‑hour ABPM.
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Revisiting the affect regulation model of binge eating: a meta-analysis of studies using ecological momentary assessment.
Haedt-Matt, AA, Keel, PK
Psychological bulletin. 2011;(4):660-681
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Abstract
The affect regulation model of binge eating, which posits that patients binge eat to reduce negative affect (NA), has received support from cross-sectional and laboratory-based studies. Ecological momentary assessment (EMA) involves momentary ratings and repeated assessments over time and is ideally suited to identify temporal antecedents and consequences of binge eating. This meta-analytic review includes EMA studies of affect and binge eating. Electronic database and manual searches produced 36 EMA studies with N = 968 participants (89% Caucasian women). Meta-analyses examined changes in affect before and after binge eating using within-subjects standardized mean gain effect sizes (ESs). Results supported greater NA preceding binge eating relative to average affect (ES = 0.63) and affect before regular eating (ES = 0.68). However, NA increased further following binge episodes (ES = 0.50). Preliminary findings suggested that NA decreased following purging in bulimia nervosa (ES = -0.46). Moderators included diagnosis (with significantly greater elevations of NA prior to bingeing in binge eating disorder compared to bulimia nervosa) and binge definition (with significantly smaller elevations of NA before binge vs. regular eating episodes for the Diagnostic and Statistical Manual of Mental Disorders definition compared to lay definitions of binge eating). Overall, results fail to support the affect regulation model of binge eating and challenge reductions in NA as a maintenance factor for binge eating. However, limitations of this literature include unidimensional analyses of NA and inadequate examination of affect during binge eating, as binge eating may regulate only specific facets of affect or may reduce NA only during the episode.
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Effects of biodiversity and plant community composition on productivity in semiarid grasslands of Hulunbeir, Inner Mongolia, China.
Zheng, XX, Liu, GH, Fu, BJ, Jin, TT, Liu, ZF
Annals of the New York Academy of Sciences. 2010;:E52-64
Abstract
Many recent studies have focused on the relationship between biodiversity and ecosystem functioning, such as investigations into the productivity of experimental plant communities. One of the central issues affecting the functioning of ecosystems is the diversity of resident species richness and the composition of the plant community. However, one challenge to experimental studies is that results from artificial ecosystems may have little value for predicting loss of diversity and function degradation in natural ecosystems. Thus, recent studies have focused more on investigations of natural ecosystems; these studies have found that species diversity and ecosystem productivity usually correlate with various abiotic factors including environmental effects, such as soil nutrition and precipitation, as well as anthropic activities, such as grazing and agricultural yield. In this study, we aimed to test the validity of biotic factors reported in experimental studies to be major factors affecting the productivity of ecosystems, and then to determine whether the relationship between biodiversity and ecosystem function is confounded by environmental factors. We investigated the effects of plant biodiversity and community composition on ecosystem function (productivity) in semiarid grassland in Inner Mongolia, China that contained three vegetation types: arid steppe, steppe, and meadow steppe. Our results show that both diversity and community composition significantly affect productivity and are better predictors of productivity than environmental factors, such as soil conditions. Our findings are consistent with the assumptions of niche complementarity. This study suggests that both biodiversity and community composition are important biotic factors in the functioning of ecosystems located in semiarid grasslands. In addition, environmental parameters, such as soil conditions influence productivity indirectly by affecting both biotic factors at the same time.
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Suitability of the OCDE tests to estimate contamination with 2,4-dichlorophenol of soils from Galicia (NW Spain).
Moscoso, F, Bouzas, S, Gil-Sotres, F, Leirós, MA, Trasar-Cepeda, C
The Science of the total environment. 2007;(1-2):58-62
Abstract
The objective of the present study was to verify whether the generic reference levels (GRL) for soils contaminated with 2,4-dichlorophenol (2,4 DCP), established by Spanish legislation and published in the Real Decreto 9/2005, are accurate for Galician soils. For this, the surface horizons of seven soils under different types of land use were experimentally contaminated with different doses (between 0 and 10,000 times the GRL) of 2,4 DCP, and were then were subject to OECD toxicity test numbers 208 (root emergence and elongation) and 216 (soil nitrogen mineralization). The results obtained for the nitrogen mineralization test were difficult to interpret because they varied among soils, whereas the results of the root germination and elongation test were more coherent -- the values decreased with increasing doses of contaminant added to the soil. The results suggest that the root elongation test reflects the effect of this contaminant more clearly than the soil nitrogen mineralization test. Nevertheless, considering that in the lowest quality soils (i.e. agricultural soils containing a very low level of organic matter) contaminant doses of up to 1000 times the GRL did not affect root germination and elongation, it is clear that the GRL indicated in the relevant legislation are very low for the soils under study and that the threshold should be established taking into account the soil characteristics.
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Infant doses from the transfer of radionuclides in mothers' milk.
Harrison, JD, Smith, TJ, Phipps, AW
Radiation protection dosimetry. 2003;(1-4):251-6
Abstract
Assessments of potential internal exposures of the child following radionuclide intakes by the mother require consideration of transfers during lactation as well as during pregnancy. Current ICRP work on internal dosimetry includes the estimation of radiation doses to newborn infants from radionuclides ingested in mothers' milk. Infant doses will be calculated for maternal intakes by ingestion or inhalation of the radionuclides, radioisotopes of 31 elements, for which fetal dose coefficients have been published. In this paper, modelling approaches are examined, concentrating on models developed for iodine, caesium, polonium, alkaline earth elements and the actinides. Comparisons of model predictions show maximum overall transfer to milk following maternal ingestion during lactation of about 30% of ingested activity for 131I, 20% for 45Ca and 137Cs, 10% for 90Sr, 1% for 210Po and low values of less than 0.01% for 239Pu and 241Am. The corresponding infant doses from milk consumption are estimated in preliminary calculations to be about two to three times the adult dose for 45Ca and 131I, 70-80% of the adult dose for 90Sr, about 40% for 137Cs, 20% for 210Po, and <0.1% for 239Pu and 241Am. Infant doses from radionuclides in breast milk are compared with doses to the offspring resulting from in utero exposures during pregnancy.
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Inclusion of micronuclei in non-divided mononuclear lymphocytes and necrosis/apoptosis may provide a more comprehensive cytokinesis block micronucleus assay for biomonitoring purposes.
Kirsch-Volders, M, Fenech, M
Mutagenesis. 2001;(1):51-8
Abstract
Human biomonitoring of early genetic effects requires accurate, sensitive and, if possible, easy and not too time-consuming methodologies to assess mutations. One of the most promising methodologies at the present time is the cytokinesis block micronucleus (MN) assay (CBMN), which detects both chromosome breakage and chromosome loss in once-divided binucleated (BN) cells. Many studies have been published with this methodology, but before its extensive application is recommended, it is necessary to evaluate its strengths and limitations. Recently, Fenech et al. reviewed the advantages of the CBMN assay for biomonitoring purposes. However, up to now information present in mononucleated (MONO) cells has rarely been taken into account, although it might be complementary to that assessed in BN cells. Indeed, MONO cells should indicate damage which was present in vivo before the start of culture and BN cells may contain pre-existing micronuclei (MNi) plus lesions which are expressed as MNi during in vitro culture. To address this question, the objectives of this paper were as follows. (i) To situate the CBMN assay in a historical and mechanistic perspective. (ii) To consider whether impaired mitotic capacity in vitro may be responsible for false negative biomonitoring studies if MN in MONO cells are not taken into account in the CBMN test. The following factors were considered: division delay for repair and mitotic block, in vitro apoptosis and necrosis of damaged cells, mitotic slippage and correlation between MN expression in vitro versus in vivo. (iii) To analyse the factors which may cause a negative result in the CBMN assay in biomonitoring when exposure to specific genotoxins is evident. The specific effects of aneugens and of adaptive responses to chronic low level exposure were examined. (iv) To compare the sensitivity of MONO and BN cells in relation to the genotoxic mechanism. (v) To propose an adequate sampling scheme to study MN in both MONO and BN cells. It was concluded that a more comprehensive assessment of DNA damage may be achieved if the CBMN assay includes measures of: (i) MNi in MONO cells; (ii) MNi in BN cells; (iii) apoptotic cells; (iv) necrotic cells. It is probable that the 24 h post-phytohaemagglutinin time point may be the optimal time to assess the frequency of MNi in MONO cells, apoptotic cells and necrotic cells. It is also practical to include these measures when scoring MNi in BN cells after cytokinesis block.