The effect of cattle slurry in combination with nitrate and the nitrification inhibitor dicyandiamide on in situ nitrous oxide and dinitrogen emissions

peer-reviewedA field study was conducted to determine the effect of the nitrification inhibitor dicyandiamide (DCD) on N2O and N2 emissions after cattle slurry (CS) application in the presence of nitrate (NO3) fertiliser on seven different occasions (between March 2009 and March 2011). N2O emissions from CS in the presence of NO3 fertiliser were very high (0.4–8.7% of applied N) over a 20-day period, under mild moist conditions. Emissions were significantly larger from the CS treatment compared to an NH4+-N source, supplying the same rate of N as in the slurry. This study supports the view that organic fertilisers should not be applied at the same time as nitrate-based fertilisers, as significant increases in N2O emissions occur. The average N2O mole fraction (N2O/(N2O + N2)) over all seven application dates was 0.34 for CSNO3 compared to 0.24 for the NH4ClNO3 treatment, indicating the dominance of N2 emissions. The rate of nitrification in CSNO3 was slower than in NH4ClNO3, and DCD was found to be an effective nitrification inhibitor in both treatments. However, as N2O emissions were found to be predominantly associated with the NO3 pool, the effect of DCD in lowering N2O emissions is limited in the presence of a NO3 fertiliser. To obtain the maximum cost-benefit of DCD in lowering N2O emissions, under mild moist conditions, it should not be applied to a nitrate containing fertiliser (e.g. ammonium nitrate or calcium ammonium nitrate), and therefore the application of DCD should be restricted to ammonium-based organic or synthetic fertilisers.This research was funded by the Irish National Development Plan, through the Research Stimulus Fund (RSF 07 519), administered by the Irish Department of Agriculture, Food and the Marine

Confirmation of co-denitrification in grazed grassland

peer-reviewedPasture-based livestock systems are often associated with losses of reactive forms of nitrogen (N) to the environment. Research has focused on losses to air and water due to the health, economic and environmental impacts of reactive N. Di-nitrogen (N2) emissions are still poorly characterized, both in terms of the processes involved and their magnitude, due to financial and methodological constraints. Relatively few studies have focused on quantifying N2 losses in vivo and fewer still have examined the relative contribution of the different N2 emission processes, particularly in grazed pastures. We used a combination of a high 15N isotopic enrichment of applied N with a high precision of determination of 15N isotopic enrichment by isotope-ratio mass spectrometry to measure N2 emissions in the field. We report that 55.8 g N m−2 (95%, CI 38 to 77 g m−2) was emitted as N2 by the process of co-denitrification in pastoral soils over 123 days following urine deposition (100 g N m−2), compared to only 1.1 g N m−2 (0.4 to 2.8 g m−2) from denitrification. This study provides strong evidence for co-denitrification as a major N2 production pathway, which has significant implications for understanding the N budgets of pastoral ecosystems.The authors are grateful for the funding that was provided through the Research Stimulus Fund Program administered by the Department of Agriculture & Food under the National Development Plan 2007–2013 RSF 07536. The first author is grateful for the funding provided by Teagasc through the Walsh Fellowship Scheme

Mentoring Qualitative Research Authors Globally: The Qualitative Report Experience

Authoring quality qualitative inquiry is a challenge for most researchers. A lack of local mentors can make writing even more difficult. To meet this need, The Qualitative Report ( TQR ) has helped authors from around the world develop their papers into published articles. TQR editorial team members will discuss the history of the journal, their philosophy of author development; manuscript development strategies; solutions for managing differences; challenges working worldwide; authors’ feedback; and the collective global futures of TQR and qualitative researche

Delocalization of electrons in a Random Magnetic Field

Delocalization problem for a two-dimensional non-interacting electron system is studied under a random magnetic field. With the presence of a random magnetic field, the Hall conductance carried by each eigenstate can become nonzero and quantized in units of $e^2/h$. Extended states are characterized by nonzero Hall conductance, and by studying finite-size scaling of the density of extended states, an insulator-metal phase transition is revealed. The metallic phase is found at the center of energy band which is separated from the localized states at the band tails by critical energies $\pm E_c$. Both localization exponent and the critical energy $E_c$ are shown to be dependent on the strength of random magnetic field.Comment: 9 pages, Revtex, 3 figures available upon reques

Simplification of soil biota communities impairs nutrient recycling and enhances above- and belowground nitrogen losses

Agriculture is a major source of nutrient pollution, posing a threat to the earth system functioning. Factors determining the nutrient use efficiency of plant-soil systems need to be identified to develop strategies to reduce nutrient losses while ensuring crop productivity. The potential of soil biota to tighten nutrient cycles by improving plant nutrition and reducing soil nutrient losses is still poorly understood. We manipulated soil biota communities in outdoor lysimeters, planted maize, continuously collected leachates, and measured N$_{2}$ O- and N$_{2}$ -gas emissions after a fertilization pulse to test whether differences in soil biota communities affected nutrient recycling and N losses. Lysimeters with strongly simplified soil biota communities showed reduced crop N (-20%) and P (-58%) uptake, strongly increased N leaching losses (+65%), and gaseous emissions (+97%) of N$_{2}$ O and N$_{2}$ . Soil metagenomic analyses revealed differences in the abundance of genes responsible for nutrient uptake, nitrate reduction, and denitrification that helped explain the observed nutrient losses. Soil biota are major drivers of nutrient cycling and reductions in the diversity or abundance of certain groups (e.g. through land-use intensification) can disrupt nutrient cycling, reduce agricultural productivity and nutrient use efficiency, and exacerbate environmental pollution and global warming

La influencia de la posición anatómica sobre la capacidad de retención del agua y sobre la blandura de la carne de caballo

Cilj istraživanja bio je utvrditi sposobnost zadržavanja vode (kalo odmrzavanja, kalo kuhanja) i mekoću (silu presijecanja) najdužeg leđnog mišića (LT) i polutetivastog mišića (ST) konjskog mesa izuzetih nakon uobičajene klaoničke prakse. Prosječna vrijednost kala odmrzavanja LT mišića bila je 8,65 %, dok je prosječna vrijednost kala odmrzavanja ST mišića bila 6,69 %. Prosječna vrijednost kala kuhanja LT mišića bila je 19,35 %. Znatno veća prosječna vrijednost kala kuhanja utvrđena je u ST mišiću (23,41 %). Prosječna vrijednost sile presijecanja LT mišića bila je 28,10 N. Prosječna vrijednost sile presijecanja ST mišića bila je znatno veća od one utvrđene u LT mišiću te je iznosila 45,64 N. Usporednom analizom razlika srednjih vrijednosti kala odmrzavanja, kala kuhanja i mekoće utvrđene su statistički značajne razlike između LT i ST (p<0,0001) mišića konjskog mesa. Nadalje, rezultati potvrđuju umjereno visoku i pozitivnu korelaciju (r=0,60; p<0,0001) kala odmrzavanja između LT i ST mišića. Zaključno, anatomska pozicija je čimbenik kojeg je potrebno uzeti u obzir ne samo u istraživanjima nego i pri tehnološkoj obradi te izboru i kupnji konjskog mesa.The aim of the study was to investigate water-holding capacity (thawing loss, cooking loss) and tenderness (shear force) of longissimus thoracis muscle (LT) and semitendinosus muscle (ST) of horse meat. The thawing loss value for LT muscle was 8.65%, whereas for ST muscle was 6.69%. The cooking loss for LT muscle was 19.35%, whereas for ST muscle was 23.41%. The shear force for LT muscle was 28.10 N, whereas for ST muscle was higher (45.64 N). Paired t-test analysis showed significant differences for thawing loss, cooking loss, and shear force between LT and ST muscles (p<0.0001). Furthermore, the results showed high correlation (r=0.60; p<0.0001) for cooking loss between LT and ST muscles. Finally, it could be concluded that the anatomical location is a trait that surely must be considered in further investigations, in meat processing and purchasing of horse meat.Ziel dieser Arbeit bestand darin, das Wasserhaltevermögen (Wasserverlust beim Auftauen, Wasserverlust beim Kochen) und die Zartheit (Scherkraft) des längsten Rückenmuskels (LT) und des halbsehnigen Muskels (ST) beim Pferdefleisch zu untersuchen, deren Proben nach der üblichen Schlachtpraxis entnommen wurde. Der durchschnittliche Wert des Wasserverlusts beim Auftauen betrug beim LT Muskel 8,65%, während der durchschnittliche Wert des Wasserverlusts beim Auftauen beim ST Muskel 6,69% betrug. Der durchschnittliche Wert des Verlusts beim Kochen betrug beim LT Muskel 19,35%, während beim ST Muskel ein bedeutend höherer mittlerer Wert des Verlusts beim Kochen festgelegt wurde (23,41%). Der mittlere Wert der Scherkraft betrug beim LT Muskel 28,10 N. Der mittlere Wert der Scherkraft beim ST Muskel war mit einem Wert von 45,64 N bedeutend höher als beim LT Muskel. Bei einer vergleichenden Auswertung der mittleren Werte des Verlusts beim Auftauen, Kochen und bei der Zartheit wurden zwischen dem LT und ST Muskel beim Pferdefleisch statistisch relevante Unterschiede festgestellt (p<0,0001). Die Ergebnisse bestätigen darüber hinaus eine relativ hohe und positive Korrelation (r=0,60; p<0,0001) des Verlustes beim Auftauen zwischen dem LT und ST Muskel. Als Schlussfolgerung kann konstatiert werden, dass die anatomische Lage ein Faktor ist, der nicht nur bei Untersuchungen berücksichtigt werden sollte, sondern auch bei der technologischen Verarbeitung sowie bei der Wahl und dem Kauf von Pferdefleisch.Lo scopo della ricerca è consistito nell\u27accertare la capacità di trattenere l\u27acqua (calo da scongelamento, calo da cottura) e la tenerezza (forza di taglio) del muscolo lunghissimo (LT) e del muscolo semitendinoso (ST) della carne equina prelevati dopo la consueta prassi di macellazione. Circa il calo da scongelamento del muscolo LT, la ricerca ha evidenziato un valore medio dell\u278,65%, mentre, riguardo al calo da scongelamento del muscolo ST, ha evidenziato un valore medio del 6,69%. Circa il calo da cottura del muscolo LT, la ricerca ha evidenziato un valore medio del 19,35%. Il valore medio del calo da cottura evidenziato riguardo al muscolo ST è stato di molto maggiore (23,41%). Il valore medio della forza di taglio del muscolo LT è risultato di 28,10 N. Il valore medio della forza di taglio del muscolo ST, pari a 45,64 N, è risultato molto maggiore del valore medio registrato riguardo al muscolo LT. Mediante l\u27analisi comparativa delle differenze dei valori medi del calo da scongelamento, del calo da cottura e della tenerezza, sono state accertate differenze statisticamente significative tra il muscolo LT e il muscolo ST (p<0,0001) della carne equina. I risultati confermano anche una correlazione mediamente elevata e positiva (r=0,60; p<0,0001) del calo da scongelamento tra i muscoli LT e ST. In conclusione, la posizione anatomica è un fattore che va preso in considerazione non soltanto in sede di ricerca, ma anche nel processo tecnologico, nella scelta e nell\u27acquisto della carne equina.El fin de esta investigación fue determinar la capacidad de retención del agua (merma por descongelación, merma por cocción) y la blandura (fuerza de corte) del músculo más largo de la espalda (LT) y el músculo ST de la carne de caballo tomadas después de la práctica habitual en el matadero. El valor medio de la merma por descongelación del músculo LT fue 8,65%, mientras el valor medio de la merma por descongelación del músculo ST fue 6,69%. El valor medio de la merma por cocción del músculo LT fue 19,35%. El valor medio de la merma por cocción del músculo ST fue considerablemente más alto, (23,41%). El valor medio de la fuerza de corte del músculo LT fue 28,10 N. El valor medio de la fuerza de corte del músculo ST fue considerablemente más alto que el valor determinado para el músculo LT y fue 45,64 N. Por el análisis comparativo de los valores medio de la merma por descongelación, de la merma por cocción y de la blandura fueron determinadas diferencias estadísticamente significantes entre los músculos LT y ST (p<0,0001) de carne de caballo. Además, los resultados confirman la correlación positiva moderada (r=0,60; p<0,0001) de la merma por descongelación entre los músculos LT y ST. En conclusión, la posición anatómica es un factor que hay que tomar en cuenta no sólo en las investigaciones sino también durante el procesamiento tecnológico y en la compra de la carne de caballo

Planet Occurrence within 0.25 AU of Solar-type Stars from Kepler

We report the distribution of planets as a function of planet radius (R_p), orbital period (P), and stellar effective temperature (Teff) for P < 50 day orbits around GK stars. These results are based on the 1,235 planets (formally "planet candidates") from the Kepler mission that include a nearly complete set of detected planets as small as 2 Earth radii (Re). For each of the 156,000 target stars we assess the detectability of planets as a function of R_p and P. We also correct for the geometric probability of transit, R*/a. We consider first stars within the "solar subset" having Teff = 4100-6100 K, logg = 4.0-4.9, and Kepler magnitude Kp < 15 mag. We include only those stars having noise low enough to permit detection of planets down to 2 Re. We count planets in small domains of R_p and P and divide by the included target stars to calculate planet occurrence in each domain. Occurrence of planets varies by more than three orders of magnitude and increases substantially down to the smallest radius (2 Re) and out to the longest orbital period (50 days, ~0.25 AU) in our study. For P < 50 days, the radius distribution is given by a power law, df/dlogR= k R^\alpha. This rapid increase in planet occurrence with decreasing planet size agrees with core-accretion, but disagrees with population synthesis models. We fit occurrence as a function of P to a power law model with an exponential cutoff below a critical period P_0. For smaller planets, P_0 has larger values, suggesting that the "parking distance" for migrating planets moves outward with decreasing planet size. We also measured planet occurrence over Teff = 3600-7100 K, spanning M0 to F2 dwarfs. The occurrence of 2-4 Re planets in the Kepler field increases with decreasing Teff, making these small planets seven times more abundant around cool stars than the hottest stars in our sample. [abridged]Comment: Submitted to ApJ, 22 pages, 10 figure

Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures

Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo

Association Between Diabetes Obesity And Short Term Outcomes Among Patients Surgically Treated For Ankle Fracture

Background: Although obesity is widely accepted as a risk factor for surgical complications following orthopaedic surgery, the literature is unclear with regard to the effect of obesity on outcomes of ankle fracture surgery, particularly in the setting of competing risks from diabetes. We hypothesized that obesity would be independently associated with more frequent complications, longer hospital length of stay, and higher costs of care among patients with and without diabetes. Methods: With use of data from 2001 to 2010 from the Nationwide Inpatient Sample, we identified all adult patients who underwent surgical treatment for a primary diagnosis of an isolated ankle fracture or dislocation. We then divided patients into four groups according to the presence or absence of diabetes or obesity: Group A included patients with neither diagnosis; Group B, obesity alone; Group C, diabetes alone; and Group D, both diagnoses. Multivariable regression models were constructed to determine the association between diagnostic group and in-hospital complications, hospital length of stay, and imputed costs of care, while controlling for other conditions. Results: The final sample included 148,483 patients (78.4% in Group A, 5.0% in Group B, 13.6% in Group C, and 3.0% in Group D). The median age was 53.0 years, and most patients (62.2%) were female and had a closed bimalleolar or trimalleolar fracture (62.2%). In the unadjusted analysis, the frequency of in-hospital complications (2.6%, 4.2%, 5.3%, and 6.5% in Groups A, B, C, and D, respectively; p \u3c 0.001), length of stay (3.0, 3.6, 4.4, and 4.8 days, respectively; p \u3c 0.001), and costs of care ($9686,$10,555, $11,616, and$12,804, respectively, in 2010 U.S. dollars; p \u3c 0.001) increased across groups. Patients with obesity alone (Group B) (adjusted odds ratio [OR] = 1.4; 95% confidence interval [CI] = 1.3 to 1.6), diabetes alone (Group C) (OR = 1.1; 95% CI = 1.0 to 1.2), and both diagnoses (Group D) (OR = 1.4; 95% CI = 1.2 to 1.5) had more frequent in-hospital complications than those with neither diagnosis. Conclusions: We found that patients with concurrent diagnoses of diabetes and obesity had higher health-care utilization and costs than those with neither diagnosis or with obesity alone or diabetes alone. The delay in the diagnosis of diabetes may somewhat obscure the true effect. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence

Association Between Diabetes Obesity And Short Term Outcomes Among Patients Surgically Treated For Ankle Fracture

Background: Although obesity is widely accepted as a risk factor for surgical complications following orthopaedic surgery, the literature is unclear with regard to the effect of obesity on outcomes of ankle fracture surgery, particularly in the setting of competing risks from diabetes. We hypothesized that obesity would be independently associated with more frequent complications, longer hospital length of stay, and higher costs of care among patients with and without diabetes. Methods: With use of data from 2001 to 2010 from the Nationwide Inpatient Sample, we identified all adult patients who underwent surgical treatment for a primary diagnosis of an isolated ankle fracture or dislocation. We then divided patients into four groups according to the presence or absence of diabetes or obesity: Group A included patients with neither diagnosis; Group B, obesity alone; Group C, diabetes alone; and Group D, both diagnoses. Multivariable regression models were constructed to determine the association between diagnostic group and in-hospital complications, hospital length of stay, and imputed costs of care, while controlling for other conditions. Results: The final sample included 148,483 patients (78.4% in Group A, 5.0% in Group B, 13.6% in Group C, and 3.0% in Group D). The median age was 53.0 years, and most patients (62.2%) were female and had a closed bimalleolar or trimalleolar fracture (62.2%). In the unadjusted analysis, the frequency of in-hospital complications (2.6%, 4.2%, 5.3%, and 6.5% in Groups A, B, C, and D, respectively; p \u3c 0.001), length of stay (3.0, 3.6, 4.4, and 4.8 days, respectively; p \u3c 0.001), and costs of care ($9686,$10,555, $11,616, and$12,804, respectively, in 2010 U.S. dollars; p \u3c 0.001) increased across groups. Patients with obesity alone (Group B) (adjusted odds ratio [OR] = 1.4; 95% confidence interval [CI] = 1.3 to 1.6), diabetes alone (Group C) (OR = 1.1; 95% CI = 1.0 to 1.2), and both diagnoses (Group D) (OR = 1.4; 95% CI = 1.2 to 1.5) had more frequent in-hospital complications than those with neither diagnosis. Conclusions: We found that patients with concurrent diagnoses of diabetes and obesity had higher health-care utilization and costs than those with neither diagnosis or with obesity alone or diabetes alone. The delay in the diagnosis of diabetes may somewhat obscure the true effect. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence