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1.
Phys Rev Lett ; 128(13): 132002, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35426724

RESUMEN

The first measurement of lepton-jet momentum imbalance and azimuthal correlation in lepton-proton scattering at high momentum transfer is presented. These data, taken with the H1 detector at HERA, are corrected for detector effects using an unbinned machine learning algorithm (multifold), which considers eight observables simultaneously in this first application. The unfolded cross sections are compared with calculations performed within the context of collinear or transverse-momentum-dependent factorization in quantum chromodynamics as well as Monte Carlo event generators.

2.
Eur Phys J C Part Fields ; 77(11): 791, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-31997933

RESUMEN

The strong coupling constant α s is determined from inclusive jet and dijet cross sections in neutral-current deep-inelastic ep scattering (DIS) measured at HERA by the H1 collaboration using next-to-next-to-leading order (NNLO) QCD predictions. The dependence of the NNLO predictions and of the resulting value of α s ( m Z ) at the Z-boson mass m Z are studied as a function of the choice of the renormalisation and factorisation scales. Using inclusive jet and dijet data together, the strong coupling constant is determined to be α s ( m Z ) = 0.1157 ( 20 ) exp ( 29 ) th . Complementary, α s ( m Z ) is determined together with parton distribution functions of the proton (PDFs) from jet and inclusive DIS data measured by the H1 experiment. The value α s ( m Z ) = 0.1142 ( 28 ) tot obtained is consistent with the determination from jet data alone. The impact of the jet data on the PDFs is studied. The running of the strong coupling is tested at different values of the renormalisation scale and the results are found to be in agreement with expectations.

3.
Environ Manage ; 54(5): 935-50, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25156863

RESUMEN

It has become increasingly clear that desertification can only be tackled through a multi-disciplinary approach that not only involves scientists but also stakeholders. In the DESIRE project such an approach was taken. As a first step, a conceptual framework was developed in which the factors and processes that may lead to land degradation and desertification were described. Many of these factors do not work independently, but can reinforce or weaken one another, and to illustrate these relationships sustainable management and policy feedback loops were included. This conceptual framework can be applied globally, but can also be made site-specific to take into account that each study site has a unique combination of bio-physical, socio-economic and political conditions. Once the conceptual framework was defined, a methodological framework was developed in which the methodological steps taken in the DESIRE approach were listed and their logic and sequence were explained. The last step was to develop a concrete working plan to put the project into action, involving stakeholders throughout the process. This series of steps, in full or in part, offers explicit guidance for other organizations or projects that aim to reduce land degradation and desertification.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Modelos Teóricos , Desarrollo de Programa , Política Pública , Clima Desértico , Restauración y Remediación Ambiental/tendencias , Humanos
4.
Poult Sci ; 85(8): 1383-8, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16903468

RESUMEN

For application in broiler production, we developed a multispecies (MSPB) and a chicken-specific (CSPB) probiotic preparation in fluid form. The MSPB contained different probiotic species of human origin, whereas the CSPB consisted of 7 Lactobacillus species isolated from the digestive tract of chickens. In a field trial with broilers, MSPB treatment resulted in a slight increase (by 1.84%) in broiler productivity based on an index taking into account daily weight gain, feed efficiency, and mortality. The CSPB treatment reduced mortality in 2 subsequent field trials and raised productivity by 2.94 and 8.70%. In a controlled trial with broilers showing a high index of productivity, probiotic treatment further raised productivity by 3.72%. Based on the present 4 studies in combination with 9 studies published earlier, it is suggested that with higher productivity rates of the broilers the effect of probiotics becomes smaller.


Asunto(s)
Pollos/crecimiento & desarrollo , Ingestión de Energía/efectos de los fármacos , Lactobacillus/crecimiento & desarrollo , Probióticos , Aumento de Peso/efectos de los fármacos , Animales , Antibiosis , Concentración de Iones de Hidrógeno , Lactobacillus/fisiología , Masculino , Mortalidad , Enfermedades de las Aves de Corral/prevención & control , Probióticos/administración & dosificación , Distribución Aleatoria
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