Formaldehyde over the central Pacific during PEM-Tropics B

Formaldehyde, CH2O, mixing ratios are reported for the central Pacific troposphere from a series of 41 flights, which took place in March-April 1999 as part of the NASA Pacific Exploratory Mission (PEM) -Tropics B mission. Ambient CH2O was collected in aqueous media and quantified using an enzyme-derivatization fluorescence technique. Primary calibration was performed using aqueous standards and known flow rates. Occasionally, CH2O gas standard additions to ambient air were performed as a secondary calibration. Analytical blanks were determined by replacing ambient air with pure air. The estimated precision was ±30 pptv and the estimated accuracy was the sum of ±30 parts per trillion by volume (pptv) ±15% of the measured value. Approximately 25% of the observations were less than the instrumental detection limit of 50 pptv, and 85% of these occurred above 6 km. CH2O mixing ratios decreased with altitude; for example, near the equator the median value in the lowest 2 km was 275 pptv, decreased to 150 pptv by 6 km and was below 100 pptv above 8 km. Between 130 and 170 W and below 1km, a small variation of CH2O mixing ratio with latitude was noted as near-surface median mixing ratios decreased near the equator (275 pptv) and were greater on either side (375 pptv). A marked decrease in near-surface CH2O (200 pptv) was noted south of 23° S on two flights. Between 3° and 23° S, median CH2O mixing ratios were lower in the eastern tropical Pacific than in the western or central Pacific; nominal differences were >100 pptv near the surface to ∼100 pptv at midaltitude to ∼50 pptv at high altitude. Off the coast of Central America and Mexico, mixing ratios as high as 1200 pptv were observed in plumes that originated to the east over land. CH2O observations were consistently higher than the results from a point model constrained by other photochemical species and meteorological parameters. Regardless of latitude or longitude, agreement was best at altitudes above 4 km where the difference between measured and modeled CH2O medians was less than 50 pptv. Below 2 km the model median was approximately 150 pptv less than the measured median. Copyright 2001 by the American Geophysical Union

π→lνγ\pi \to l\nu \gamma Form Factors at Two-loop

Within Chiral Perturbation Theory (CHPT) we compute the form factors A, V and $\gamma = A/V$ in the $\pi \to \nu l \gamma$ decay to $O(p^6)$. A and $\gamma$ obtain corrections of order 25%.Comment: Added cut-off dependence discusion, misprints correcte

Complex patterns of schist tor exposure and surface uplift, Otago (New Zealand)

Landscapes are subjected to surface denudation during their complex and non-linear evolution. In order to quantify the in situ surface lowering and, thus, denudation or soil erosion rates, new, multi-millennia archives are needed and must be rigorously tested. Large residual rocks, tors, are the basis for the Tor Exhumation Approach. Here we present novel results on meta-sedimentary (schist) rock tors using this approach, which previously has only been applied in granitic terrains. The exhumation patterns of eight schist tors in three landscape locations (valley, ridge, distal) of Otago, New Zealand, were studied using cosmogenic dating. The in situ 10Be ages have high variability along individual vertical tor profiles. Average surface age is 122 ± 12 ka and ranges from 836 ± 89 ka to 19 ± 2 ka. The majority of investigated tors have surfaced during the MIS 5 which was one of the wettest and warmest climate periods. The resulting surface denudation trend of the three locations differs. The valley commenced denudation no earlier than ~200 ka with rates of ~0.22 [m kyr−1] to ~0.02 [m kyr−1]. In contrast, exposure started at the ridge position around 230 ka at ~0.03 [m kyr−1]. An age inversion found in the valley is considered to be the result of mushroom-like exposure by undercutting and repeated rock breakoffs. The distal site tor has been exhumed continuously for ~120 ka at a rate of ~0.2 to ~0.05 [m kyr−1]. We identified a mix of surface emergence patterns of the tors such as continuous-, mushroom-, tafoni- and structural-like. The comparison to modern erosion rates indicates that surface erosion has increased up to a factor of ten during the last few decades. To determine the actual surface uplift, we linked the tor derived surface denudation rates with rock uplift data. The data indicates that the surface uplift rates started to decrease during the Middle Pleistocene (0.04–0.09 [m kyr−1]), remained relatively low during the Late Pleistocene (~0.01 [m kyr−1]) and started to increase again during the Holocene (c. 0.21–0.64 [m kyr−1]). In summary, the emergence pattern of local tors enabled reconstruction of the evolution of Pleistocene-Holocene surfaces in East Otago

Effect of Heavy Metal Contaminated Shooting Range Soils on Mycorrhizal Colonization of Roots and Metal Uptake by Leek

We grew leek (Allium porrum) in soils of two shooting ranges heavily contaminated with heavy metals in the towns of Zuchwil and Oberuzwil in Switzerland as a bioassay to test theactivity of arbuscular mycorrhizal (AM) fungi in these soils.Soil samples were taken from (1) front of the shooting house(HOUSE), (2) the area between house and target (FIELD) and (3) the berm (BACKSTOP). Samples of Ribwort plantain (Plantagolanceolata) growing naturally within the shooting ranges werealso collected and the colonization of its roots by mycorrhizalfungi was measured. The number of AM spores in the soils wassignificantly reduced concomitant with the increase in thedegree of soil contamination with metals. In Zuchwil,mycorrhizal fungi equally colonized roots of Ribwort plantainsampled from BACKSTOP and HOUSE. In Oberuzwil, however, plantsfrom BACKSTOP had lower colonization when compared with thosesampled from HOUSE. Colonization of leek was strongly reducedin the BACKSTOP soil of Zuchwil and slightly reduced in theBACKSTOP soil of Oberuzwil when compared with plants grown inrespective HOUSE soil. Concentrations of Cd, Cr, Cu, Ni, Pb andZn in the leaves of leek grown in the BACKSTOP soil was withinthe range considered toxic for human consumption. This pointsto the high degree of bio-availability of these metal in thesesoils. Significant decrease in the number of mycorrhizal sporesin the BACKSTOP soils in Zuchwil and the low colonization ofleek roots grown in these soils point to possible changes inthe species diversity of mycorrhizal fungi in these soil

Emergency department visits for non-life-threatening conditions : evolution over 13 years in a Swiss urban teaching hospital

INTRODUCTION: A large proportion of visits to our Emergency Department (ED) are for non-life-threatening conditions. We investigated whether patients' characteristics and reasons for consultation had changed over 13 years. METHODS: Consecutive adult patients with non-life-threatening conditions at triage were included in the spring of 2000 and in the summer of 2013. In both years patients completed a similar questionnaire, which addressed their reasons for consultation and any previous consultation with a general practitioner (GP). RESULTS: We included 581 patients in 2013 vs 516 in 2000, with a mean age of 44.5 years vs 46.4 years (p=0.128). Of these patients, 54.0% vs 57.0% were male (p=0.329), 55.5% vs 58.7% were Swiss (p=0.282), 76.4% were registered with a GP in both periods, but self-referral increased from 52.0% to 68.8% (p<0.001); 57.7% vs., 58.3% consulted during out-of- hours (p=0.821). Trauma-related visits decreased from 34.2% to 23.7% (p<0.001). Consultations within 12 hours of onset of symptoms dropped from 54.5% to 30.9%, and delays of ≥1 week increased from 14.3% to 26.9% (p<0.001). The primary motive for self-referral remained unawareness of an alternative, followed in 2013 by dissatisfaction with the GP's treatment or appointment. Patients who believed that their health problem would not require hospitalisation increased from 52.8% to 74.2% and those who were actually hospitalised decreased from 24.9% to 13.9% (all p<0.001). CONCLUSION: The number of visits for non-life-threatening consultations continue to increase. Our ED is used by a large proportion of patients as a convenient alternative source of primary care

Detection of noninteracting single domain particles using first-order reversal curve diagrams

We present a highly sensitive and accurate method for quantitativedetection and characterization of noninteracting or weakly interactinguniaxial single domain particles (UNISD) in rocks and sediments. Themethod is based on high-resolution measurements of first-order reversalcurves (FORCs). UNISD particles have a unique FORC signature that can beused to isolate their contribution among other magnetic components. Thissignature has a narrow ridge along the H(c) axis of the FORC diagram,called the central ridge, which is proportional to the switching fielddistribution of the particles. Therefore, the central ridge is directlycomparable with other magnetic measurements, such as remanentmagnetization curves, with the advantage of being fully selective to SDparticles, rather than other magnetic components. This selectivity isunmatched by other magnetic unmixing methods, and offers usefulapplications ranging from characterization of SD particles forpaleointensity studies to detecting magnetofossils and ultrafineauthigenically precipitated minerals in sediments

Stabilizing contributions of sulfur-modified nucleotides: crystal structure of a DNA duplex with 2′-O-[2-(methoxy)ethyl]-2-thiothymidines

Substitution of oxygen atoms by sulfur at various locations in the nucleic acid framework has led to analogs such as the DNA phosphorothioates and 4′-thio RNA. The phosphorothioates are excellent mimics of DNA, exhibit increased resistance to nuclease degradation compared with the natural counterpart, and have been widely used as first-generation antisense nucleic acid analogs for applications in vitro and in vivo. The 4′-thio RNA analog exhibits significantly enhanced RNA affinity compared with RNA, and shows potential for incorporation into siRNAs. 2-Thiouridine (s(2)U) and 5-methyl-2-thiouridine (m(5)s(2)U) are natural nucleotide analogs. s(2)U in tRNA confers greater specificity of codon–anticodon interactions by discriminating more strongly between A and G compared with U. 2-Thio modification preorganizes the ribose and 2′-deoxyribose sugars for a C3′-endo conformation, and stabilizes heteroduplexes composed of modified DNA and complementary RNA. Combination of the 2-thio and sugar 2′-O-modifications has been demonstrated to boost both thermodynamic stability and nuclease resistance. Using the 2′-O-[2-(methoxy)ethyl]-2-thiothymidine (m(5)s(2)Umoe) analog, we have investigated the consequences of the replacement of the 2-oxygen by sulfur for base-pair geometry and duplex conformation. The crystal structure of the A-form DNA duplex with sequence GCGTAT*ACGC (T* = m(5)s(2)Umoe) was determined at high resolution and compared with the structure of the corresponding duplex with T* = m(5)Umoe. Notable changes as a result of the incorporation of sulfur concern the base-pair parameter ‘opening’, an improvement of stacking in the vicinity of modified nucleotides as measured by base overlap, and a van der Waals interaction between sulfur atoms from adjacent m(5)s(2)Umoe residues in the minor groove. The structural data indicate only minor adjustments in the water structure as a result of the presence of sulfur. The observed small structural perturbations combined with the favorable consequences for pairing stability and nuclease resistance (when combined with 2′-O-modification) render 2-thiouracil-modified RNA a promising candidate for applications in RNAi