2,124 research outputs found
A Simplified Model of Nitrogen Flows from Manure Management
This report describes a model to simulate release processes of trace gases from manure into the atmosphere. This "manure handling model" (MHM) provides a mass-consistent scheme to follow nitrogen and carbon compounds along the typical stages of manure treatment in animal husbandry. In each of the model compartments, which reflect the respective stages, conversion between reactive and unreactive nitrogen or carbon species is possible, as well as the release of gaseous compounds from the reactive species. We use total ammoniacal nitrogen (TAN) as the reactive nitrogen species, and degradable volatile solid (VSd) as the reactive carbon species. Conversion parameters, either derived from specific information, e.g. national data, or as default values, allow assessing transformation rates. As a result, the model generates emission factors for the release of nitrogen components (gaseous NH3, N2O, NOx, N2 and NO3 -- in runoff and the associated N2O emission) and CH4 for use in IIASA's integrated assessment model GAINS.
Results of MHM have been compared with the German emission model GAS-EM for dairy cattle on liquid manure to demonstrate that the simplified model is able to reflect complex national information. With identical input parameters, the simplified model reproduces results of the more complex models within 1% difference for the emission of all N components and emission of CH4. MHM was also used with default input (excretion rates, emission coefficients and removal factors) to generate emission factors for all possible combinations of animals and control strategies for all European countries. However, a comparison with current GAINS emission factors reveals substantial differences due to country-specific information that is available in GAINS
Integrated Nitrogen Management in China
Providing China's growing population with higher quality food and a larger share of meat in diets can only be accomplished through increased agricultural productivity, which is usually achieved through higher input of nitrogen to soils. This can lead to nitrate leaching which affects the quality of drinking water, causes emissions of ammonia to the atmosphere, a contributor to the formation of atmospheric particles that are harmful to human health, and to the release of nitrous oxide (N2O), an important global greenhouse gas.
This report develops an integrated perspective on agricultural management measures that have multiple benefits on economic development, on the local environment and for global greenhouse gas emissions. The study estimates for the case of China that an integrated nitrogen management approach could increase agricultural production by up to 50 percent while keeping current levels of nitrogen discharge to soil, water and air at the local scale. Compared to the business as usual case, emissions of N2O greenhouse gas emissions would be 25 percent lower.
Developed as an activity of IIASA's interdisciplinary Greenhouse Gas Initiative (GGI), the new integrated approach links population increase and demands on food quality with nitrogen fertilizer requiremnts in agriculture, and assesses undesired environmental effects of nitrogen at the local and global scales
Pulse Sequence Resilient Fast Brain Segmentation
Accurate automatic segmentation of brain anatomy from
-weighted~(-w) magnetic resonance images~(MRI) has been a
computationally intensive bottleneck in neuroimaging pipelines, with
state-of-the-art results obtained by unsupervised intensity modeling-based
methods and multi-atlas registration and label fusion. With the advent of
powerful supervised convolutional neural networks~(CNN)-based learning
algorithms, it is now possible to produce a high quality brain segmentation
within seconds. However, the very supervised nature of these methods makes it
difficult to generalize them on data different from what they have been trained
on. Modern neuroimaging studies are necessarily multi-center initiatives with a
wide variety of acquisition protocols. Despite stringent protocol harmonization
practices, it is not possible to standardize the whole gamut of MRI imaging
parameters across scanners, field strengths, receive coils etc., that affect
image contrast. In this paper we propose a CNN-based segmentation algorithm
that, in addition to being highly accurate and fast, is also resilient to
variation in the input -w acquisition. Our approach relies on building
approximate forward models of -w pulse sequences that produce a typical
test image. We use the forward models to augment the training data with test
data specific training examples. These augmented data can be used to update
and/or build a more robust segmentation model that is more attuned to the test
data imaging properties. Our method generates highly accurate, state-of-the-art
segmentation results~(overall Dice overlap=0.94), within seconds and is
consistent across a wide-range of protocols.Comment: Accepted at MICCAI 201
STRUKTUR KOMUNITAS MANGROVE DI DESA LESAH, KECAMATAN TAGULANDANG, KABUPATEN SITARO
Mangroves are forests that grow in brackish water and are affected by tides and seawater, and these forests grow specifically in places where there are pavement and accumulation of organic material. The purpose of this research is to identify the types of mangroves and determine the structure of the mangrove community in Lesah Village. This research was conducted from September to October 2019. The method used in this research is the quadrant line transect method. The types of mangroves were identified with identification books. Community structure data taken are density, frequency, dominance and important value index (IVI) and then analyzed with Microsoft Excel program. Based on the results of the research, there are 2 types of mangroves found in the research location, Rhizophora stylosa and Sonneratia alba. The highest density value (0.122 ind / m2), relative density (81.88%), frequency types (1), relative frequency (50%). Closure types (1.83 m2), types of relative closure (50.18%), the highest important value index at the research site was (182.12%). The results of the mangrove ecological index data analysis for the diversity index value (0.51), dominance (0.73). Keywords: Structure Community, Mangrove, Lesah Village. Abstrak Mangrove adalah hutan yang tumbuh di air payau, dan dipengaruhi oleh pasang surut air laut dan hutan ini tumbuh khususnya di tempat-tempat di mana terjadi pelumpuaran dan akumulasi bahan oraganik. Tujuan dari penelitian adalah mengidentifikasi jenis-jenis mangrove dan mengetahui struktur komunitas mangrove di Desa Lesah. Penelitian dilaksanakan dari September-Oktober 2019. Metode yang digunakan adalah metode line transek kuadran. Jenis-jenis mangrove di identifikasi dengan bantuan buku identifikasi. Data struktur komunitas yang di ambil adalah kerepatan, ferkuensi, dominasi dan indeks nilai penting(INP) dan kemudian di analisa dengan bantuan program computer Microsoft Excel. Berdasarkan hasil penelitian terdapat 2 jenis mangrove yang terdiri dari, Rhizophora stylosa dan Sonneratia alba. Nilai kerepatan tertinggi (0.122 ind/m2), kerapatan relatif jenis (81.88%), frekuensi jenis (1), frekuensi relatif jenis (50%). Penutupan jenis (1.83 m2), penutupan relatif jenis (50.18%), indeks nilai penting tertinggi dilokasi penelitian adalah (182.12%). Hasil analisis data indeks ekologi mangrove untuk nilai indeks keanekaragaman (0.51), dominasi(0.73). Kata Kunci: Struktur Komunitas, Mangrove, Desa Lesah
Integrated assessment of air pollution and greenhouse gases mitigation in Europe
Paper discusses integrated assessment methodology of air pollution and greenhouse gases mitigation. RAINS/GAINS model developed at the International Institute for Applied Systems Analysis (IIASA) is described. Its use in policy-relevant analysis is discussed with particular focus on studies for the development of policies of the European Union and under the UN/ECE Convention on Long-Range Transboundary Air Pollution (CLRTAP). Importance of interactions and synergies between air pollution and greenhouse gases policies is stressed. Integrated assessment has proven to be an important tool for preparation of air pollution control legislation in Europe. Although most prominent applications of integrated assessment referred to international policies, recently these methods have been applied in several national studies for in-depth analyses at sub-national regional level. It is advisable to further disseminate applications of the methodology and software tools for regional assessment
Extraction of parabens from cosmetic and environmental water samples coupled with uv-visible spectroscopy
An effective and fast vortex-assisted dispersive liquid–liquid extraction method was developed for the extraction of
paraben in cosmetic samples and water samples. The paraben was determined and quantifi ed using ultraviolet-visible
(UV-Vis) spectrometry. A response surface methodology (RSM) based on the central composite design was used for
the optimization of factors (composition of the extractant, volume of extractant, extraction time, centrifugation time,
and centrifugation velocity) affecting the extraction effi ciency of the procedure. The optimum parameters for vortexassisted
dispersive liquid–liquid extraction (VA-DLLE) are: chloroform used as the extractant solvent, 5 ml volume
of extractant, 3 min extraction time, 5 min centrifugation time, and 2400 rpm centrifugation velocity. The limit of
detection (LOD) and the limit of quantifi cation (LOQ) for paraben are 0.0476 and 0.1442 μg/mL, respectively.
Spiked cosmetic samples have the extraction recoveries in the range of 81.2–96.8%, whereas spiked water sample
extraction recoveries were in the range of 88.8–100.63%. Each sample was repeated (n = 2), with a relative standard
deviation of <5.74% for cosmetic samples and <9.03% for water samples. In conclusion, this extraction method is
fast and inexpensive for the extraction of paraben
Study of Zγ events and limits on anomalous ZZγ and Zγγ couplings in pp̄ collisions at s=1.96TeV
We present a measurement of the Zγ production cross section and limits on anomalous ZZγ and Zγγ couplings for form-factor scales of Λ=750 and 1000 GeV. The measurement is based on 138 (152) candidates in the eeγ (μμγ) final state using 320(290)pb-1 of pp̄ collisions at s=1.96TeV. The 95% C.L. limits on real and imaginary parts of individual anomalous couplings are |h10,30Z|<0.23, |h20,40Z|<0.020, |h10,30γ|<0.23, and |h20,40γ|<0.019 for Λ=1000GeV. © 2005 The American Physical Society
Search for associated production in collisions at
This report describes a search for associated production of and Higgs
bosons based on data corresponding to an integrated luminosity of collected with the D0 detector at the Fermilab
Tevatron Collider. Events containing a
candidate (with corresponding to or ) are selected in
association with two or three reconstructed jets. One or two of the jets are
required to be consistent with having evolved from a quark. A multivariate
discriminant technique is used to improve the separation of signal and
backgrounds. Expected and observed upper limits are obtained for the product of
the production cross section and branching ratios and reported in terms of
ratios relative to the prediction of the standard model as a function of the
mass of the Higgs boson (). The observed and expected 95% C.L. upper
limits obtained for an assumed are, respectively, factors
of 4.5 and 4.8 larger than the value predicted by the standard model.Comment: 25 pages, 14 figure
Search for first generation leptoquark pair production in the electron + missing energy + jets final state
We present a search for the pair production of first generation scalar
leptoquarks (LQ) in data corresponding to an integrated luminosity of 5.4
fb collected with the D0 detector at the Fermilab Tevatron Collider in
ppbar collisions at TeV. In the channel , where q, q' are u or d quarks, no significant excess
of data over background is observed, and we set a 95% C.L. lower limit of 326
GeV on the leptoquark mass, assuming equal probabilities of leptoquark decays
to eq and .Comment: 7 pages, 6 figures, submitted to PRD-R
A search for W bb and W Higgs production in ppbar collisions at sqrt(s)=1.96 TeV
We present a search for W b \bar{b} production in p \bar{p} collisions at
sqrt{s}=1.96 TeV in events containing one electron, an imbalance in transverse
momentum, and two b-tagged jets. Using 174 pb-1 of integrated luminosity
accumulated by the D0 experiment at the Fermilab Tevatron collider, and the
standard-model description of such events, we set a 95% C.L. upper limit on W b
\bar{b}WH--$135
GeV.Comment: 7 pages, 4 figures, 1 table, submitted to Physical Review Letter
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