Comparison of indices for the prediction of nitrogen mineralization after destruction of managed grassland

Intensively managed grasslands are occasionally chemically killed with herbicide and ploughed in order to grow an arable crop. After this management, large N mineralization rates with large losses to the environment are commonly observed. However, it remains to be determined to what extent the chemical killing contribute to increased N mineralization. In this study the potential nitrogen (N) mineralization from grasslands, that were killed with herbicides but otherwise undisturbed, was investigated in a laboratory experiment with undisturbed soil columns. Subsequently we assessed the predictive value of several laboratory indices for N mineralization after chemically killing of the grass. Mineralization rates varied from 0.5 to 3.0 g N m-2 wk-1. The contents of total N, total C, dissolved organic carbon (DOC) and hot-KCl extractable NH4 + were best related to N mineralization rates (R2=50, 48, 38 and 47%, respectively). In combination with information on the N content of the roots and stubble and the age of grassland at destruction, up to 62% of the variation in N mineralization rates could be explained. Although previous studies suggested that dissolved organic nitrogen (DON) is a good indicator for mineralization rates, this was not the case after chemically killing grass in the current study

Haematological studies on some freshwater teleosts

No Abstrac

Method and timing of grassland renovation affects herbage yield, nitrate leaching, and nitrous oxide emission in intensively managed grasslands

Managed grasslands are occasionally ploughed up and reseeded in order to maintain or increase the sward productivity. It has been reported that this renovation of grassland is associated with a flush of soil organic nitrogen (N) mineralization and with a temporary increase in soil mineral N contents. Here, we report on the effects of method and time of grassland renovation on herbage yield, nitrate (NO3 -) leaching and nitrous oxide (N2O) emission. Field experiments were carried out at three sites (two sandy soils and a clay soil) in the Netherlands for three years. Renovation of grassland increased the percentage of Perennial ryegrass from 48–70% up to more than 90%. However, averaged over three years, dry matter yields were higher for the reference (not reseeded) swards (on average 13.6 Mg ha-1 for the highest N application rate) than for the renovated grasslands (12.2–13.1 Mg ha-1 dry matter). Grassland renovation in April did not increase N leaching in comparison to the reference. However, renovation in September increased the risk of leaching, because mineral N contents in the 0–90 cm were in November on average 46–77 kg N ha-1 higher than in the reference. Contents of dissolved organic N (DON) in the soil were not affected by renovation. Renovation increased N2O emissions by a factor of 1.8–3.0 relative to the reference grassland. Emissions of N2O were on average higher after renovation in April (8.2 kg N2O-N ha-1) than in September (5.8 kg N2O-N ha-1). Renovation without ploughing (i.e. only chemically destruction of the sward) resulted in a lower percentage of perennial ryegrass (60–84%) than with ploughing (>90%). Moreover, N2O emissions were higher after renovation without ploughing than with ploughing. Clearly, farmers need better recommendations and tools for determining when grassland renovation has beneficial agronomic effects. Losses of N via leaching and N2O emission after renovation can probably not be avoided, but renovation in spring in stead of autumn in combination with ploughing and proper timing of fertilizer application can minimize N losses

Five-year follow-up of participants diagnosed with chronic airflow obstruction in a South African Burden of Obstructive Lung Disease (BOLD) survey

Background. A community-based prevalence survey performed in two suburbs in Cape Town, South Africa (SA), in 2005, using the international Burden of Obstructive Lung Disease (BOLD) method, confirmed a prevalence of chronic airflow obstruction (CAO) in 23.1% of adults aged >40 years.Objectives. To study the clinical course and prognosis over 5 years of patients with CAO identified in the 2005 survey.Methods. Patients with CAO in 2005 were invited to participate. Standard BOLD and modified questionnaires were completed. Spirometry was performed using spirometers of the same make as in 2005.Results. Of 196 eligible participants from BOLD 2005, 45 (23.0%) had died, 8 from respiratory causes, 10 from cardiovascular causes and 6 from other known causes, while in 21 cases the cause of death was not known. On multivariate analysis, only age and Global initiative for Obstructive Lung Disease (GOLD) stage 4 disease at baseline were significantly associated with death. Of the 151 survivors, 11 (5.6% of the original cohort) were unavailable and 33 (16.8%) declined or had medical exclusions. One hundred and seven survivors were enrolled in the follow-up study (54.6%, median age 63.1 years, 45.8% males). Post-bronchodilator spirometry performed in 106 participants failed to confirm CAO, defined as a forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) ratio of <0.7, in 16 participants (15.1%), but CAO was present in 90. The median decline in FEV1 was 28.9 mL/year (interquartile range –54.8 - 0.0) and was similar between GOLD stages. The median total decline in FVC was 75 mL, and was significantly greater in GOLD stage 1 (–350 mL) than in stages 2 or 3 (–80 mL and +140 mL, respectively; p<0.01). Fifty-eight participants with CAO in 2005 (64.4%) remained in the same GOLD stage, while 21 (23.3%) deteriorated and 11 (12.2%) improved by ≥1 stage. Only one-third were receiving any treatment for chronic obstructive pulmonary disease (COPD).Conclusions. The prevalence, morbidity and mortality of CAO and COPD in SA are high and the level of appropriate treatment is very low, pointing to underdiagnosis and inadequate provision of and access to effective treatments and preventive strategies for this priority chronic non-communicable disease

Ontwikkeling van een indicator om te sturen op nitraat; gegevens en regressie-analyse voor het eerste meetseizoen (2000-2001)

In het project STuren OP NITraat wordt gezocht naar verbanden tussen zogenaamde kandidaat-indicatoren voor de nitraatbelasting van het grondwater. Na analyse van de gegevens van één meetseizoen (2000/2001) komt in ieder geval de indeling in drie Gt-groepen naar voren als een verklarende factor voor het niveauverschil in de gemeten nitraatconcentraties in het voorjaar van 2001. De hoeveelheid Nmin in oktober-december 2000, gesommeerd over de drie bodemlagen (i.e. 0-90 cm), komt naar voren als het meest geschikt als indicator voor nitraatuitspoeling. Opschaling naar bedrijfsniveau resulteert in een voorspelling op basis van rekenregels van de bedrijfsgemiddelde nitraatconcentratie in het grondwater met een veel lagere voorspelfout dan wanneer op puntniveau voorspellingen worden gedaan. Dit biedt zicht op een praktisch toepasbare indicator op bedrijfsniveau

Ontwikkeling van een indicator om te sturen op nitraat; toetsing van de regressiemodellen voor nitraat

Binnen het project ¿Sturen op Nitraat¿ zijn regressiemodellen ontwikkeld. In dit rapport wordt op verschillende manieren getoetst hoe nauwkeurig de nitraatconcentratie uit waarnemingen aan de indicatoren kan worden voorspeld met behulp van de regressiemodellen. Dit wordt gedaan op basis van de metingen van het vierde meetseizoen. Het blijkt dat nieuwe meetpunten veelal binnen de 95-%-betrouwbaarheidsintervallen van de voorspelling vallen, wanneer deze is gebaseerd op de meest eenvoudige modellen en de gemeten Nminnitraat. Dit eenvoudige model, met bodem-Gt-gewas-combinatie (cluster) en Nminnitraat is bovendien het meest stabiele en praktisch toepasbare mode

Ontwikkeling van een indicator om te sturen op nitraat; gegevens en regressieanalyse op basis van drie meetseizoenen (2000-2001, 2001-2002 en 2002-2003)

In het project `Sturen op Nitraat¿ wordt gezocht naar indicatoren waarmee de nitraatconcentratie in het grondwater kan worden voorspeld. Uit een analyse van de meetresultaten van drie meetseizoenen (2000/2001, 2001/2002 en 2002/2003) blijkt dat de nitraatconcentratie het best kan worden voorspeld uit het nitraatgedeelte van de hoeveelheid Nmineraal die zich in het najaar in de bovenste 90 cm van de bodem bevindt, en een clusterindeling die is gebaseerd op een combinatie van bodemsoort, grondwatertrap en gewas. Het verdient aanbeveling te onderzoeken of het nitraatdeel van Nmineraal bruikbaar is voor sturing op bedrijfsniveau (beïnvloedbaarheid), of voor monitoring van effecten van maatregelen (doelgerichtheid en meetbaarheid)

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02

"4D Biology for health and disease" workshop report

The "4D Biology Workshop for Health and Disease", held on 16-17th ofMarch 2010 in Brussels, aimed at finding the best organising principlesfor large-scale proteomics, interactomics and structural genomics/biology initiatives, and setting the vision for future high-throughputresearch and large-scale data gathering in biological and medical science.Major conclusions of the workshop include the following. (i)Development of new technologies and approaches to data analysis iscrucial. Biophysical methods should be developed that span a broadrange of time/spatial resolution and characterise structures andkinetics of interactions. Mathematics, physics, computational andengineering tools need to be used more in biology and new tools needto be developed. (ii) Database efforts need to focus on improveddefinitions of ontologies and standards so that system-scale data andassociated metadata can be understood and shared efficiently. (iii)Research infrastructures should play a key role in fosteringmultidisciplinary research, maximising knowledge exchange betweendisciplines and facilitating access to diverse technologies. (iv)Understanding disease on a molecular level is crucial. Systemapproaches may represent a new paradigm in the search for biomarkersand new targets in human disease. (v) Appropriate education andtraining should be provided to help efficient exchange of knowledgebetween theoreticians, experimental biologists and clinicians. Theseconclusions provide a strong basis for creating major possibilities inadvancing research and clinical applications towards personalisedmedicine.Biophysical Structural Chemistr