Mercury Content of Waters in the Midcontinent Region

Two major areas of the midcontinent region were investigated for their aqueous mercury concentrations. Sixteen surface water and 17 ground water samples were collected in an eleven county area of N.W. Arkansas, S.W. Missouri and N.E. Oklahoma (Ozark area) and analyzed for total dissolved mercury by the flameless atomic absorption spectrophotometric method. The range (\u3c0.2 to 0.8 ppb), the mean (0.4 ppb) and the median (0.4 ppb) are the same for both ground water and surface water. Values obtained for the Ozark area are slightly greater than those reported for surface water by others (about 0.1 ppb), but are well within the range reported for surface waters (0.1 to 17.0 ppb). The range for 102 ground water samples from the Ouachita Mountain area is \u3c0.1 to 2.3 ppb, the mean 0.3 ppb and the median 0.1 ppb. Thus, the mercury values for this area are similar to those of the Ozark area except fora higher upper range. The mercury mineralization (cinnabar) in the southern part of the Ouachita Mountain area, in part, is the cause of the higher values. Only two samples (2.1 and 2.3 ppb), both from the Ouachita Mountain area, exceed the EPA drinking water limits of 2 ppb mercury in the western Arkansas region

Hot medium effects on J/psi production in p+Pb collisions at sqrt{s_{NN}}=5.02 TeV

Based on a kinetic description of J/psi dissociation and production in an expanding quark-gluon plasma that is described by a 2+1 dimensional ideal hydrodynamics, we have studied the hot medium effects on J/psi production in p+Pb collisions at sqrt{s_{NN}}=5.02 TeV. Including also the cold nuclear matter effects, we are able to reproduce recent experimental results on the nuclear modification factor R_{pPb}(J/psi) measured by the ALICE Collaboration. We have also made predictions for the R_{pPb} of J/psi and the double ratio R_{pPb}^{pro}(psi')/R_{pPb}^{pro}(J/psi) of prompt quarkonia produced in the most central 10% p+Pb collisions. We find that different from the cold nuclear matter effects, the R_{pPb}(J/psi) is slightly smaller than that in the minimum bias collisions, and the double ratio is significantly less than one at backward rapidity.Comment: 8 pages, 6 figure

Determination of metal ion content of beverages and estimation of target hazard quotients : a comparative study

Background: Considerable research has been directed towards the roles of metal ions in nutrition with metal ion toxicity attracting particular attention. The aim of this study is to measure the levels of metal ions found in selected beverages (red wine, stout and apple juice) and to determine their potential detrimental effects via calculation of the Target Hazard Quotients (THQ) for 250 mL daily consumption. Results: The levels (mean ± SEM) and diversity of metals determined by ICP-MS were highest for red wine samples (30 metals totalling 5620.54 ± 123.86 ppb) followed by apple juice (15 metals totalling 1339.87 ± 10.84 ppb) and stout (14 metals totalling 464.85 ± 46.74 ppb). The combined THQ values were determined based upon levels of V, Cr, Mn, Ni, Cu, Zn and Pb which gave red wine samples the highest value (5100.96 ± 118.93 ppb) followed by apple juice (666.44 ± 7.67 ppb) and stout (328.41 ± 42.36 ppb). The THQ values were as follows: apple juice (male 3.11, female 3.87), stout (male 1.84, female 2.19), red wine (male 126.52, female 157.22) and ultra-filtered red wine (male 110.48, female 137.29). Conclusion: This study reports relatively high levels of metal ions in red wine, which give a very high THQ value suggesting potential hazardous exposure over a lifetime for those who consume at least 250 mL daily. In addition to the known hazardous metals (e.g. Pb), many metals (e.g. Rb) have not had their biological effects systematically investigated and hence the impact of sustained ingestion is not known

Participatory Plant Breeding Methods for Organic Cereals

Formal breeding methods were not always suitable to address the very large diversity of both environmental conditions and end-user needs. Both were frequently encountered either in marginal areas of developing countries or in organic farms of EEC. Participatory plant breeding (PPB) methods represent alternatives aimed to improve local adaptation breeding, to promote genetic diversity, to empower farmers and rural communities. The term PPB refers to a set of breeding methods usually distinguished by the objectives (functional or process approach), institutional context (farmer-led or formal-led), forms of interaction between farmers and breeders (consultative, collaborative or collegial), location of breeding (centralized or decentralized), stage of farmers participation in the breeding scheme (participatory varietal selection or participatory plant breeding)… Among all these methods, the best strategies for organic breeding and their impacts on breeding techniques are discussed. A PPB program actually conducted at INRA – Montpellier (F), involves the whole organic durum wheat interprofessional organization, from farmers to consumers. It is used to assess the interest of a multidisciplinary approach and to discuss the role of each participant in such program. Must participation be seen as a means towards an end or an end in itself

Trace chemical measurements from the northern midlatitude lowermost stratosphere in early spring: Distributions, correlations, and fate

In situ measurements of a large number of trace chemicals from the midlatitude (37-57°N) lower stratosphere were performed with the NASA DC-8 aircraft during March 1994. Deepest penetrations into the stratosphere (550 ppb O3, 279 ppb N2O, and 350 K potential temperature) corresponded to a region that has been defined as the "lowermost stratosphere" (LS) by Holton et al [1995]. Analysis of data shows that the mixing ratios of long-lived tracer species (e. g. CH4, HNO3, NOy, CFCs) are linearly correlated with those of O3 and N2O. A ΔNOy/ΔO3 of 0.0054 ppb/ppb and ΔNOy/ΔN2O of -0.081 ppb/ppb is in good agreement with other reported measurements from the DC-8. These slopes are however, somewhat steeper than those reported from the ER-2 airborne studies. We find that the reactive nitrogen budget in the LS is largely balanced with HNO3 accounting for 80% of NOy, and PAN and NOx together accounting for 5%. A number of oxygenated species (e. g. acetone, H2O2) were present and may provide an important in situ source of HOx in the LS. SO2 mixing ratios were found to increase in the stratosphere at a rate that was comparable to the decline in OCS levels. No evidence of particle formation could be observed. Ethane, propane, and acetylene mixing ratios declined rapidly in the LS with Cl atoms likely playing a key role in this process. A number of reactive hydrocarbons/halocarbons (e. g. C6H6, CH3I) were present at low but measurable concentrations

Multiparticle correlation studies in pPb collisions at √s_(NN) = 8.16 TeV

The second- and third-order azimuthal anisotropy Fourier harmonics of charged particles produced in pPb collisions, at √s_(NN) = 8.16, are studied over a wide range of event multiplicities. Multiparticle correlations are used to isolate global properties stemming from the collision overlap geometry. The second-order “elliptic” harmonic moment is obtained with high precision through four-, six-, and eight-particle correlations and, for the first time, the third-order “triangular” harmonic moment is studied using four-particle correlations. A sample of peripheral PbPb collisions at √s_(NN)= 5.02 TeV that covers a similar range of event multiplicities as the pPb results is also analyzed. Model calculations of initial-state fluctuations in pPb and PbPb collisions can be directly compared to the high-precision experimental results. This work provides new insight into the fluctuation-driven origin of the v3 coefficients in pPb and PbPb collisions, and into the dominating overall collision geometry in PbPb collisions at the earliest stages of heavy ion interactions

Fresh air in the 21st century?

Ozone is an air quality problem today for much of the world's population. Regions can exceed the ozone air quality standards (AQS) through a combination of local emissions, meteorology favoring pollution episodes, and the clean-air baseline levels of ozone upon which pollution builds. The IPCC 2001 assessment studied a range of global emission scenarios and found that all but one projects increases in global tropospheric ozone during the 21st century. By 2030, near-surface increases over much of the northern hemisphere are estimated to be about 5 ppb (+2 to +7 ppb over the range of scenarios). By 2100 the two more extreme scenarios project baseline ozone increases of >20 ppb, while the other four scenarios give changes of -4 to +10 ppb. Even modest increases in the background abundance of tropospheric ozone might defeat current AQS strategies. The larger increases, however, would gravely threaten both urban and rural air quality over most of the northern hemisphere

Ozone effects on blood biomarkers of systemic inflammation, oxidative stress, endothelial function, and thrombosis: The Multicenter Ozone Study in oldEr Subjects (MOSES).

The evidence that exposure to ozone air pollution causes acute cardiovascular effects is mixed. We postulated that exposure to ambient levels of ozone would increase blood markers of systemic inflammation, prothrombotic state, oxidative stress, and vascular dysfunction in healthy older subjects, and that absence of the glutathione S-transferase Mu 1 (GSTM1) gene would confer increased susceptibility. This double-blind, randomized, crossover study of 87 healthy volunteers 55-70 years of age was conducted at three sites using a common protocol. Subjects were exposed for 3 h in random order to 0 parts per billion (ppb) (filtered air), 70 ppb, and 120 ppb ozone, alternating 15 min of moderate exercise and rest. Blood was obtained the day before, approximately 4 h after, and approximately 22 h after each exposure. Linear mixed effect and logistic regression models evaluated the impact of exposure to ozone on pre-specified primary and secondary outcomes. The definition of statistical significance was p<0.01. There were no effects of ozone on the three primary markers of systemic inflammation and a prothrombotic state: C-reactive protein, monocyte-platelet conjugates, and microparticle-associated tissue factor activity. However, among the secondary endpoints, endothelin-1, a potent vasoconstrictor, increased from pre- to post-exposure with ozone concentration (120 vs 0 ppb: 0.07 pg/mL, 95% confidence interval [CI] 0.01, 0.14; 70 vs 0 ppb: -0.03 pg/mL, CI -0.09, 0.04; p = 0.008). Nitrotyrosine, a marker of oxidative and nitrosative stress, decreased with increasing ozone concentrations, with marginal significance (120 vs 0 ppb: -41.5, CI -70.1, -12.8; 70 vs 0 ppb: -14.2, CI -42.7, 14.2; p = 0.017). GSTM1 status did not modify the effect of ozone exposure on any of the outcomes. These findings from healthy older adults fail to identify any mechanistic basis for the epidemiologically described cardiovascular effects of exposure to ozone. The findings, however, may not be applicable to adults with cardiovascular disease

Response Of Broiler Chickens Fed On Diets Containing Low Level Of Aflatoxin (B1 And B2) And Supplemented With Mycotoxin Binder

The objective of the present study was to evaluate the growth performance and feet colour of broilers  fed on diets containing low level of aflatoxin (B1 and B2) and mycosorb. The experimental design was a 4 x 2 factorial randomized complete design consisting of two main factors which  were aflatoxin level and mycosorb. The treatments were control diets, control diets supplemented with mycosorb, diets containing 10 ppb aflatoxin, diets containing 10 ppb aflatoxin supplemented with mycosorb, diets containing 25 ppb aflatoxin, diets containing 25 ppb aflatoxin supplemented with mycosorb, diets containing 60 ppb aflatoxin, diets containing 60 ppb aflatoxin supplemented with mycosorb. The aflatoxin levels in the experimental diets obtained by substitution the proportion of corn of the control diets with aflatoxin corn. Variables measured were feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR). Except for feet colour score, the results showed that there was no interaction (P > 0.05) between aflatoxin level and mycosorb on FI, BWG and FCR of 7d- and 14 d-old-broilers. The aflatoxin level did not affect (P > 0.05) BWG, FI and FCR (7d) but it affected (P < 0.05) the FCR (14d) and feet colour of broiler. Mycosorb did not affect (P > 0.05) all parameters observed. In conclusion, except for broiler feet colour, the supplementation of aflatoxin, mycosorb and combination between aflatoxin and mycosorb in broiler diets had no effects on the growth performance of broilers during 7 and 14 day experiment. Further research is needed to evaluate the growth performance of broilers fed diets containing high level of aflatoxin