2,366 research outputs found

    Variability in Herbage Mass and Chemical Composition within a Timothy Sward

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    Variability in herbage mass (HM) and chemical composition of timothy (Phleum pratense L.) sward was studied in a three-hectare field. The field, which was flat, was divided into twelve sections and a sampling site was randomly selected in each. The study was carried out in Sotkamo (64o 01’N, 28o22’E) research station in Finland. Snow depth and frost conditions were measured in winter and soil water content was monitored in the growing season at each sampling site. Observations on the crop included assessment of herbage ground cover and winter damage percentage, stand height and HM and analysis of neutral detergent fibre (NDF) and nitrogen concentration. Forage was harvested twice during the experiment and the first cut was made at ear emergence. Winter damage varied from 0 to 68% and herbage ground cover in spring from 30 to 100%. Variability in HM was higher at the first cut (from 1767 to 4390 kg DM ha-1) than at the second cut (from 3890 to 4348 kg DM ha-1). NDF content varied from 601 to 688 g kg-1 at the first cut and from 582 to 632 g kg-1 from at the second cut. The 95% confidence limits for NDF at the first cut were from 635 to 663 g kg-1 and at the second cut from 589 to 604 g kg-1

    Pareto optimality in multilayer network growth

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    We model the formation of multi-layer transportation networks as a multi-objective optimization process, where service providers compete for passengers, and the creation of routes is determined by a multi-objective cost function encoding a trade-off between efficiency and competition. The resulting model reproduces well real-world systems as diverse as airplane, train and bus networks, thus suggesting that such systems are indeed compatible with the proposed local optimization mechanisms. In the specific case of airline transportation systems, we show that the networks of routes operated by each company are placed very close to the theoretical Pareto front in the efficiency-competition plane, and that most of the largest carriers of a continent belong to the corresponding Pareto front. Our results shed light on the fundamental role played by multi-objective optimization principles in shaping the structure of large-scale multilayer transportation systems, and provide novel insights to service providers on the strategies for the smart selection of novel routes

    Disorders of sex development : timing of diagnosis and management in a single large tertiary center

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    Background: We describe the phenotypic spectrum and timing of diagnosis and management in a large series of patients with disorders of sexual development (DSD) treated in a single pediatric tertiary center. Methods: DSD patients who had visited our tertiary center during the survey period (between 2004 and 2014) were identified based on an ICD-10 inquiry, and their phenotypic and molecular genetic findings were recorded from patient charts. Results: Among the 550 DSD patients, 53.3% had 46,XY DSD; 37.1% had sex chromosome DSD and 9.6% had 46,XX DSD. The most common diagnoses were Turner syndrome (19.8%, diagnosed at the mean age of 4.7 +/- 5.5 years), Klinefelter syndrome (14.5%, 6.8 +/- 6.2 years) and bilateral cryptorchidism (23.1%). Very few patients with 46,XY DSD (7%) or 46,XX DSD (21%) had molecular genetic diagnosis. The yearly rate of DSD diagnoses remained stable over the survey period. After the release of the Nordic consensus on the management of undescended testes, the age at surgery for bilateral cryptorchidism declined significantly (P <0.001). Conclusions: Our results show that (i) Turner syndrome and Klinefelter syndrome, the most frequent single DSD diagnoses, are still diagnosed relatively late; (ii) a temporal shift was observed in the management of bilateral cryptorchidism, which may favorably influence patients' adulthood semen quality and (iii) next-generation sequencing methods are not fully employed in the diagnostics of DSD patients.Peer reviewe

    Seasonal cycle and source analyses of aerosol optical properties in a semi-urban environment at Puijo station in Eastern Finland

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    We introduce a four-year (in 2006–2010) continuous data set of aerosol optical properties at Puijo in Kuopio, Finland. We study the annual and diurnal variation of the aerosol scattering and absorption coefficients, hemispheric backscattering fraction, scattering Γ…ngstrΓΆm exponent, and single scattering albedo, whose median values over this period were 7.2 Mm&lt;sup&gt;βˆ’1&lt;/sup&gt; (at 550 nm), 1.0 Mm&lt;sup&gt;βˆ’1&lt;/sup&gt; (at 637 nm), 0.15, 1.93 (between 450 and 550 nm), and 0.85, respectively. The scattering coefficient peaked in the spring and autumn, being 2–4 times those in the summer and winter. An exception was the summer of 2010, when the scattering coefficient was elevated to ~300 Mm&lt;sup&gt;βˆ’1&lt;/sup&gt; by plumes from forest fires in Russia. The absorption coefficient peaked in the winter when soot-containing particles derived from biomass burning were present. The higher relative absorption coefficients resulted in lower single scattering albedo in winter. The optical properties varied also with wind direction and time of the day, indicating the effect of the local pollutant sources and the age of the particles. Peak values in the single scattering albedo were observed when the wind blew from a paper mill and from the sector without local pollutant sources. These observations were linked, respectively, to the sulphate-rich aerosol from the paper mill and the oxygenated organics in the aged aerosol, which both are known to increase the scattering characteristics of aerosols. Decreases in the single scattering albedo in the morning and afternoon, distinct in the summertime, were linked to the increased traffic density at these hours. The scattering and absorption coefficients of residential and long-range transported aerosol (two separate cloud events) were found to be decreased by clouds. The effect was stronger for the scattering than absorption, indicating preferential activation of the more hygroscopic aerosol with higher scattering characteristics

    Fluctuations, Saturation, and Diffractive Excitation in High Energy Collisions

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    Diffractive excitation is usually described by the Good--Walker formalism for low masses, and by the triple-Regge formalism for high masses. In the Good--Walker formalism the cross section is determined by the fluctuations in the interaction. In this paper we show that by taking the fluctuations in the BFKL ladder into account, it is possible to describe both low and high mass excitation by the Good--Walker mechanism. In high energy pppp collisions the fluctuations are strongly suppressed by saturation, which implies that pomeron exchange does not factorise between DIS and pppp collisions. The Dipole Cascade Model reproduces the expected triple-Regge form for the bare pomeron, and the triple-pomeron coupling is estimated.Comment: 20 pages, 12 figure

    Terpene Composition Complexity Controls Secondary Organic Aerosol Yields from Scots Pine Volatile Emissions

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    Secondary organic aerosol (SOA) impact climate by scattering and absorbing radiation and contributing to cloud formation. SOA models are based on studies of simplified chemical systems that do not account for the chemical complexity in the atmosphere. This study investigated SOA formation from a mixture of real Scots pine (Pinus sylvestris) emissions including a variety of monoterpenes and sesquiterpenes. SOA generation was characterized from different combinations of volatile compounds as the plant emissions were altered with an herbivore stress treatment. During active herbivore feeding, monoterpene and sesquiterpene emissions increased, but SOA mass yields decreased after accounting for absorption effects. SOA mass yields were controlled by sesquiterpene emissions in healthy plants. In contrast, SOA mass yields from stressed plant emissions were controlled by the specific blend of monoterpene emissions. Conservative estimates using a box model approach showed a 1.5- to 2.3-fold aerosol enhancement when the terpene complexity was taken into account. This enhancement was relative to the commonly used model monoterpene, "alpha-pinene". These results suggest that simplifying terpene complexity in SOA models could lead to underpredictions in aerosol mass loading.Peer reviewe

    Lactobacillus GG in inducing and maintaining remission of Crohn's disease

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    BACKGROUND: Experimental studies have shown that luminal antigens are involved in chronic intestinal inflammatory disorders such as Crohn's disease and ulcerative colitis. Alteration of the intestinal microflora by antibiotic or probiotic therapy may induce and maintain remission. The aim of this randomized, placebo-controlled trial was to determine the effect of oral Lactobacillus GG (L. GG) to induce or maintain medically induced remission. METHODS: Eleven patients with moderate to active Crohn's disease were enrolled in this trial to receive either L. GG (2 Γ— 10(9 )CFU/day) or placebo for six months. All patients were started on a tapering steroid regime and received antibiotics for the week before the probiotic/placebo medication was initiated. The primary end point was sustained remission, defined as freedom from relapse at the 6 months follow-up visit. Relapse was defined as an increase in CDAI of >100 points. RESULTS: 5/11 patients finished the study, with 2 patients in each group in sustained remission. The median time to relapse was 16 Β± 4 weeks in the L. GG group and 12 Β± 4.3 weeks in the placebo group (p = 0.5). CONCLUSION: In this study we could not demonstrate a benefit of L. GG in inducing or maintaining medically induced remission in CD

    NQO2 is a reactive oxygen species generating off-target for acetaminophen

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    [Image: see text] The analgesic and antipyretic compound acetaminophen (paracetamol) is one of the most used drugs worldwide. Acetaminophen overdose is also the most common cause for acute liver toxicity. Here we show that acetaminophen and many structurally related compounds bind quinone reductase 2 (NQO2) in vitro and in live cells, establishing NQO2 as a novel off-target. NQO2 modulates the levels of acetaminophen derived reactive oxygen species, more specifically superoxide anions, in cultured cells. In humans, NQO2 is highly expressed in liver and kidney, the main sites of acetaminophen toxicity. We suggest that NQO2 mediated superoxide production may function as a novel mechanism augmenting acetaminophen toxicity
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