Einfluss von Zuckerrübenblatt auf N2O-Emissionen in der Nachernteperiode - Erste Ergebnisse

Praxisüblich verbleibt die gesamte Blattmasse der Zuckerrübe auf dem Feld und kann durch das enge C/N-Verhältnis rasch mineralisiert werden. Bei der mikrobiellen Umsetzung kann u.a. die reaktive Stickstoffverbindung N2O als Nebenprodukt der Nitrifikation, aber vor allem bei der Denitrifikation entstehen. Negative Umweltwirkungen wie die Eutrophierung von Biotopen oder ein vermehrter Ozonabbau können die Folge sein. Wie hoch allerdings die N2O-Emissionen durch Blattverbleib bei Zuckerrüben tatsächlich sind und inwieweit diese durch verschiedene Anbaumaßnahmen beeinflusst werden, ist derzeit unklar. Daher wurden 2016 auf zwei Standorten in der Nähe von Göttingen Versuche zur Ermittlung der N2O-Emissionen während der Nachernteperiode angelegt. Als mögliche Einflussgrößen auf die N2O-Freisetzung wurden variiert: Blattmasse und -zusammensetzung (N-Düngung zu Zuckerrüben gering, hoch), Blatteinarbeitung (mit, ohne), Erntezeitpunkt (Mitte September, Mitte Oktober). Darüber hinaus wurden die Umweltparameter Temperatur (Luft, Boden), Niederschlag, Bodenwassergehalt sowie der Boden-Nmin-Gehalt kontinuierlich erfasst. Die N2O-Messungen erfolgten mit geschlossenen Hauben nach dem Prinzip der statischen Messkammer (Closed-Chamber-Method). Erste Ergebnisse werden auf dem Poster vorgestellt

SIGLEC1 (CD169): a marker of active neuroinflammation in the brain but not in the blood of MS patients

OBJECTIVE: We aimed to evaluate SIGLEC1 (CD169) as a biomarker in Multiple Sclerosis (MS) and Neuromyelitis optica spectrum disorder (NMOSD) and to evaluate the specificity of SIGLEC1+ myeloid cells for demyelinating diseases. METHODS: We performed flow cytometry-based measurements of SIGLEC1 expression on monocytes in 86 MS patients, 41 NMOSD patients and 31 healthy controls. Additionally, we histologically evaluated the presence of SIGLEC1+ myeloid cells in acute and chronic MS brain lesions as well as other neurological diseases. RESULTS: We found elevated SIGLEC1 expression in 16/86 (18.6%) MS patients and 4/41 (9.8%) NMOSD patients. Almost all MS patients with high SIGLEC1 levels received exogenous interferon beta as an immunomodulatory treatment and only a small fraction of MS patients without interferon treatment had increased SIGLEC1 expression. SIGLEC1+ myeloid cells were abundantly present in active MS lesions as well as in a range of acute infectious and malignant diseases of the central nervous system, but not chronic MS lesions. CONCLUSION: In our cohort, SIGLEC1 expression on monocytes was – apart from those patients receiving interferon treatment – not significantly increased in patients with MS and NMOSD, nor were levels associated with more severe disease. The presence of SIGLEC1+ myeloid cells in brain lesions could be used to investigate the activity in an inflammatory CNS lesion

Novel laser spectroscopic technique for continuous analysis of N2O isotopomers - application and intercomparison with isotope ratio mass spectrometry

RATIONALE Nitrous oxide (N2O), a highly climate-relevant trace gas, is mainly derived from microbial denitrification and nitrification processes in soils. Apportioning N2O to these source processes is a challenging task, but better understanding of the processes is required to improve mitigation strategies. The N2O site-specific 15?N signatures from denitrification and nitrification have been shown to be clearly different, making this signature a potential tool for N2O source identification. We have applied for the first time quantum cascade laser absorption spectroscopy (QCLAS) for the continuous analysis of the intramolecular 15?N distribution of soil-derived N2O and compared this with state-of-the-art isotope ratio mass spectrometry (IRMS). METHODS Soil was amended with nitrate and sucrose and incubated in a laboratory setup. The N2O release was quantified by FTIR spectroscopy, while the N2O intramolecular 15?N distribution was continuously analyzed by online QCLAS at 1?Hz resolution. The QCLAS results on time-integrating flask samples were compared with those from the IRMS analysis. RESULTS The analytical precision (2 sigma) of QCLAS was around 0.3 parts per thousand for the delta 15Nbulk and the 15?N site preference (SP) for 1-min average values. Comparing the two techniques on flask samples, excellent agreement (R2?=?0.99; offset of 1.2 parts per thousand) was observed for the delta 15Nbulk values while for the SP values the correlation was less good (R2?=?0.76; offset of 0.9 parts per thousand), presumably due to the lower precision of the IRMS SP measurements. CONCLUSIONS These findings validate QCLAS as a viable alternative technique with even higher precision than state-of-the-art IRMS. Thus, laser spectroscopy has the potential to contribute significantly to a better understanding of N turnover in soils, which is crucial for advancing strategies to mitigate emissions of this efficient greenhouse gas. Copyright (c) 2012 John Wiley & Sons, Ltd

Application of the Loo-Riegelman absorption method

The Loo-Riegelman absorption method provides the correct A ∞ /V 1 value and the correct rate constant k a (if absorption is first order), whether metabolism occurs in compartment 1 only, compartment 2 only, or both compartments 1 and 2 of the two-compartment open model. In cases where there is metabolism in compartment 2, the disposition parameters estimated from intravenous data are only apparent and not the real values. The correct A ∞ /V 1 and k a values are obtained, however, only under conditions not hithertofore specified. These conditions are that there must be essentially no bias in the disposition parameters k 12 , k 21 , and k el . and in the C 0 value estimated from the intravenous data, and that in the oral study a large number of interpolated plasma concentrations, as well as the observed plasma concentrations, must be used, especially for drugs with long half-lives. It is shown that application of the Guggenheim method to the initial A 1 V 1 , t values frequently provides a better method of estimating A ∞ /V 1 and k a than the classical method. If biased disposition parameters are used in application of the Loo-Riegelman method to oral data, then essentially the correct value of k a will be estimated, but the estimate of A ∞ /V 1 will be approximately equal to the true value of A ∞ /V 1 multiplied by the ratio of the biased C 0 value (obtained in fitting the intravenous data) to the true C 0 value of the intravenous data. The above indicates that intravenous data should be fitted by computer until there are no systematic deviations or trends and as small a sum of squared deviations as possible is obtained. The oral data should be fitted by spline or Akima methods, or similar procedures, to produce a function which passes through each observed plasma concentration and at the same time provides a large number of interpolated concentration data .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45059/1/10928_2005_Article_BF01066595.pd

SIGLEC1 (CD169): a marker of active neuroinflammation in the brain but not in the blood of multiple sclerosis patients

We aimed to evaluate SIGLEC1 (CD169) as a biomarker in multiple sclerosis (MS) and Neuromyelitis optica spectrum disorder (NMOSD) and to evaluate the presence of SIGLEC1(+) myeloid cells in demyelinating diseases. We performed flow cytometry-based measurements of SIGLEC1 expression on monocytes in 86 MS patients, 41 NMOSD patients and 31 healthy controls. Additionally, we histologically evaluated the presence of SIGLEC1(+) myeloid cells in acute and chronic MS brain lesions as well as other neurological diseases. We found elevated SIGLEC1 expression in 16/86 (18.6%) MS patients and 4/41 (9.8%) NMOSD patients. Almost all MS patients with high SIGLEC1 levels received exogenous interferon beta as an immunomodulatory treatment and only a small fraction of MS patients without interferon treatment had increased SIGLEC1 expression. In our cohort, SIGLEC1 expression on monocytes was—apart from those patients receiving interferon treatment - not significantly increased in patients with MS and NMOSD, nor were levels associated with more severe disease. SIGLEC1(+) myeloid cells were abundantly present in active MS lesions as well as in a range of acute infectious and malignant diseases of the central nervous system, but not chronic MS lesions. The presence of SIGLEC1(+) myeloid cells in brain lesions could be used to investigate the activity in an inflammatory CNS lesion

Genetic Evidence for Involvement of Neuronally Expressed S1P1 Receptor in Nociceptor Sensitization and Inflammatory Pain

Sphingosine-1-phosphate (S1P) is a key regulator of immune response. Immune cells, epithelia and blood cells generate high levels of S1P in inflamed tissue. However, it is not known if S1P acts on the endings of nociceptive neurons, thereby contributing to the generation of inflammatory pain. We found that the S1P1 receptor for S1P is expressed in subpopulations of sensory neurons including nociceptors. Both S1P and agonists at the S1P1 receptor induced hypersensitivity to noxious thermal stimulation in vitro and in vivo. S1P-induced hypersensitivity was strongly attenuated in mice lacking TRPV1 channels. S1P and inflammation-induced hypersensitivity was significantly reduced in mice with a conditional nociceptor-specific deletion of the S1P1 receptor. Our data show that neuronally expressed S1P1 receptors play a significant role in regulating nociceptor function and that S1P/S1P1 signaling may be a key player in the onset of thermal hypersensitivity and hyperalgesia associated with inflammation

Inclusive e+^+e−^- production in collisions of pions with protons and nuclei in the second resonance region of baryons

Inclusive e$^+$e$^-$ production has been studied with HADES in $\pi^-$ + p, $\pi^-$ + C and $\pi^- + \mathrm{CH}_2$ reactions, using the GSI pion beam at $\sqrt{s_{\pi p}}$ = 1.49 GeV. Invariant mass and transverse momentum distributions have been measured and reveal contributions from Dalitz decays of $\pi^0$, $\eta$ mesons and baryon resonances. The transverse momentum distributions are very sensitive to the underlying kinematics of the various processes. The baryon contribution exhibits a deviation up to a factor seven from the QED reference expected for the dielectron decay of a hypothetical point-like baryon with the production cross section constrained from the inverse $\gamma$ n$\rightarrow \pi^-$ p reaction. The enhancement is attributed to a strong four-momentum squared dependence of the time-like electromagnetic transition form factors as suggested by Vector Meson Dominance (VMD). Two versions of the VMD, that differ in the photon-baryon coupling, have been applied in simulations and compared to data. VMD1 (or two-component VMD) assumes a coupling via the $\rho$ meson and a direct coupling of the photon, while in VMD2 (or strict VMD) the coupling is only mediated via the $\rho$ meson. The VMD2 model, frequently used in transport calculations for dilepton decays, is found to overestimate the measured dielectron yields, while a good description of the data can be obtained with the VMD1 model assuming no phase difference between the two amplitudes. Similar descriptions have also been obtained using a time-like baryon transition form factor model where the pion cloud plays the major role.Comment: (HADES collaboration

Pharmacokinetics of ibuprofen in man IV: Absorption and disposition

Fifteen normal male volunters received 400, 800, and 1200 mg doses of ibuprofen as 1, 2, or 3 tablets, respectively, in crossover fashion, then 420 mg in solution form during the fourth week. Plasma concentration of ibuprofen was measured by an HPLC method. Individual subject concentration-time (C,t) data following the solution were analyzed by two different methods, and results unequivocally indicated the open two compartment model with first order absorption. However, the computer fitting of both arithmetic and geometric mean concentrations led to a different model. A method was developed to obtain absorption data (fraction of drug absorbed , F a , versus time) for a multicompartmental system from oral data alone, without intravenous data. The method assumes that V p is constant intrasubject and that absorption is complete following administration of both the solution and tablets. The method was successfully applied to the ibuprofen tablet data. It was shown also that such a method is necessary to obtain ibuprofen absorption data since intrasubject variation of the microscopic rate constants k 12 , k a21 , and k el ( as reflected by the intrasubject variation of the hybrid rate parameters λ 1 and λ 2 or Β and a) is of the same order of magnitude as intersubject variation. Absorption of ibuprofen from tablets was shown not to be simple first order as for the solution. The absorption profiles following one tablet were S- shaped, while those following 2 or 3 tablets had partial linear segments indicating zero order absorption .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45032/1/10928_2005_Article_BF01062664.pd