Fragmentation in Jets at NNLO

Beam and jet functions in Soft-Collinear Effective Theory describe collinear initial- and final-state radiation (jets), and enter in factorization theorems for N-jet production, the Higgs pT spectrum, etc. We show that they may directly be calculated as phase-space integrals of QCD splitting functions. At NLO all computations are trivial, as we demonstrate explicitly for the beam function, the transverse-momentum-dependent beam function, the jet function and the fragmenting jet function. This approach also highlights the role of crossing symmetry in these calculations. At NNLO we reproduce the quark jet function and calculate the fragmenting quark jet function for the first time. Here we use two methods: a direct phase-space integration and a reduction to master integrals which are computed using differential equations.Comment: 25 pages + Mathematica files with expressions, v2: introduction expanded, errors fixed in NNLO fragmenting jet matching coefficients (Sec. IV F), v3: journal versio

Vincia for Hadron Colliders

We present the first public implementation of antenna-based QCD initial- and final-state showers. The shower kernels are $2\to 3$ antenna functions, which capture not only the collinear dynamics but also the leading soft (coherent) singularities of QCD matrix elements. We define the evolution measure to be inversely proportional to the leading poles, hence gluon emissions are evolved in a $p_\perp$ measure inversely proportional to the eikonal, while processes that only contain a single pole (e.g., $g\to q\bar{q}$) are evolved in virtuality. Non-ordered emissions are allowed, suppressed by an additional power of $1/Q^2$. Recoils and kinematics are governed by exact on-shell $2\to 3$ phase-space factorisations. This first implementation is limited to massless QCD partons and colourless resonances. Tree-level matrix-element corrections are included for QCD up to $\mathcal{O}(\alpha_s^4)$ (4 jets), and for Drell-Yan and Higgs production up to $\mathcal{O}(\alpha_s^3)$ ($V/H$ + 3 jets). The resulting algorithm has been made publicly available in Vincia 2.0

Effect of flavor-dependent partonic transverse momentum on the determination of the WW boson mass in hadronic collisions

Within the framework of transverse-momentum-dependent factorization, we investigate for the first time the impact of a flavor-dependent intrinsic transverse momentum of quarks on the production of $W^{\pm}$ bosons in proton-proton collisions at $\sqrt{s}$ = 7 TeV. We estimate the shift in the extracted value of the $W$ boson mass $M_W$ induced by different choices of flavor-dependent parameters for the intrinsic quark transverse momentum by means of a template fit to the transverse-mass and the lepton transverse-momentum distributions of the $W$-decay products. We obtain $-6\leq \Delta M_{W^+} \leq 9$ MeV and $-4\leq \Delta M_{W^-} \leq 3$ MeV with a statistical uncertainty of $\pm 2.5$ MeV. Our findings call for more detailed investigations of flavor-dependent nonperturbative effects linked to the proton structure at hadron colliders.Comment: 5 pages, 2 tables; revised version with new results with more statistics, more comments, conclusions unchanged, added one referenc

Magnetic field control of the spin Seebeck effect

The origin of the suppression of the longitudinal spin Seebeck effect by applied magnetic fields is studied. We perform numerical simulations of the stochastic Landau-Lifshitz-Gilbert equation of motion for an atomistic spin model and calculate the magnon accumulation in linear temperature gradients for different strengths of applied magnetic fields and different length scales of the temperature gradient. We observe a decrease of the magnon accumulation with increasing magnetic field and we reveal that the origin of this effect is a field dependent change of the frequency distribution of the propagating magnons. With increasing field the magnonic spin currents are reduced due to a suppression of parts of the frequency spectrum. By comparison with measurements of the magnetic field dependent longitudinal spin Seebeck effect in YIG thin films with various thicknesses, we find that our model describes the experimental data very well, demonstrating the importance of this effect for experimental systems

Evaluation of the endotoxin binding efficiency of clay minerals using the Limulus Amebocyte lysate test: an in vitro study

Endotoxins are part of the cell wall of Gram-negative bacteria. They are potent immune stimulators and can lead to death if present in high concentrations. Feed additives, which bind endotoxins in the gastrointestinal tract of animals, could help to prevent their negative impact. The objective of our study was to determine the potential of a bentonite (Bentonite 1),a sodium bentonite (Bentonite 2),a chemically treated smectite (Organoclay 1) and a modified attapulgite (Organoclay 2) to bind endotoxins in vitro. Polymyxin B served as positive control. The kinetic chromogenic Limulus Amebocyte lysate test was adapted to measure endotoxin activity. Firstly, a single sorption experiment (10 endotoxin units/mL (EU/mL)) was performed. Polymyxin B and organoclays showed 100% binding efficiency. Secondly, the adsorption efficiency of sorbents in aqueous solution with increasing endotoxin concentrations (2, 450 - 51, 700 EU/mL) was investigated. Organoclay 1 (0.1%) showed a good binding efficiency in aqueous solution (average 81%),whereas Bentonite 1 (0.1%) obtained a lower binding efficiency (21-54%). The following absorbent capacities were calculated in highest endotoxin concentration: 5.59 mg/g (Organoclay 1) > 3.97 mg/g (Polymyxin B) > 2.58mg/g (Organoclay 2) > 1.55 mg/g (Bentonite 1) > 1.23 mg/g (Bentonite 2). Thirdly, a sorption experiment in artificial intestinal fluid was conducted. Especially for organoclays, which are known to be unspecific adsorbents, the endotoxin binding capacity was significantly reduced. In contrast, Bentonite 1 showed comparable results in artificial intestinal fluid and aqueous solution. Based on the results of this in vitro study, the effect of promising clay minerals will be investigated in in vivo trials

Reproductive performance of pandemic influenza A virus infected sow herds before and after implementation of a vaccine against the influenza A (H1N1)pdm09 virus

Background: Reproductive failure in sow herds due to infection with influenza A viruses has been described in the literature, but only a few studies have focused on the pathogenesis and the clinical signs of the infection. Case reports indicate an association between infections with influenza A viruses and reduced reproductive performance, although it has been difficult to experimentally reproduce the clinical outcome of poor reproductive performance. The aim of the present longitudinal field study was to compare the reproductive performance parameters before and after the implementation of vaccination against the influenza A (H1N1)pdm09 virus in sow herds infected with pandemic influenza A virus. Therefore, farm-specific data of 137 sow herds in Germany, including 60,153 sows, as well as the clinical presentation of the infection were surveyed via questionnaire. Furthermore, average performance parameters (return to oestrus rate, abortion rate, stillbirth rate, number of piglets born alive per litter, preweaning mortality rate and number of piglets weaned per sow per year) were recorded for 6 months before vaccination and 6 months after completion of primary vaccination. Results: In 79.8% of the farms, the clinical presentation of the infection was characterised by a reduced reproductive performance. These findings were confirmed by analysis of the performance parameters, which revealed a significant decline in the return to oestrus rate (p < 0.001), abortion rate (p < 0.001) and preweaning mortality rate (p = 0.023) and a significant increase of the number in piglets born alive (p = 0.001) and piglets weaned per sow per year (p < 0.001) after immunisation. The stillbirth rate did not change significantly. Conclusion: The present study represents the first attempt to demonstrate the association of influenza A virus infection, vaccination and the alteration in reproductive performance parameters, investigating a large number of cases. The results show that by vaccinating against the influenza A (H1N1)pdm09 virus, an improvement in reproductive performance can be achieved in sow herds infected with pandemic influenza A virus. Additionally, the large number of herds that were affected by poor reproductive performance after infection with the aforementioned virus confirms the assumption of an association between pandemic influenza A virus and reproductive losses

Antibodies to actin in autoimmune haemolytic anaemia

BACKGROUND: In autoimmune haemolytic anaemia (AIHA) autoreactive antibodies directed against red blood cells are upregulated leading to erythrocyte cell death. M. suis infections in pigs (IAP) induce AIHA of both the warm and the cold type. Aim of this study was to identify target autoantigens of warm autoreactive IgG antibodies. For this, sera from experimentally M. suis infected pigs were screened for autoreactivity. RESULTS: In sera of 95 % of all tested animals actin-reactive antibodies were found. The reactivity was shown to be species specific, i.e. reactivity with porcine actin was significantly higher than with rabbit-actin. Sera of animals previously immunised with the adhesion protein MSG1 of M. suis showed reactivity with actin prior to infection with M. suis indicating molecular mimicry to be involved in specific autoreactive mechanism. A potentially cross reactive epitope could be detected. CONCLUSIONS: This is the first report of autoreactive anti-actin antibodies involved in pathogenesis of autoimmune haemolytic anaemia

The Vincia Parton Shower

We summarize recent developments in the VINCIA parton shower. After a brief review of the basics of the formalism, the extension of VINCIA to hadron collisions is sketched. We then turn to improvements of the efficiency of tree-level matching by making the shower history unique and by incorporating identified helicities. We conclude with an overview of matching to one-loop matrix elements.Comment: 6 pages, to appear in the proceedings of DIS 201

Different sample types in pigs challenged with Haemophilus parasuis following two treatment schemes with tulathromycin

This study aimed to test the efficacy of samplings for the detection of Haemophilus parasuis after metaphylactic treatment and subsequent challenge using an established model for Glässer’s disease. In this model, 36 piglets were equally assigned to a negative control, a positive control, and two trial groups receiving tulathromycin 7 or 4 days prior to challenge. The piglets of three groups were challenged intratracheally with H. parasuis serovar 5. As a result, four pigs in each challenged group died or had to be euthanised within 10 days post challenge. The remaining 15 pigs of these challenged groups survived until termination of the experiment (days 14–15). All pigs were necropsied and collective swabs of serosal surfaces were tested by bacterial culture and PCR. Samples of tarsal synovial fluid and joint capsule, cerebrospinal fluid (CSF) and brain swabs were tested by PCR. A total of 22 out of the 27 challenged animals had macroscopically detectable polyserositis and all of them tested positive in the collective swab samples. Haemophilus parasuis was more frequently detected in pigs that died within the first 10 days compared to those surviving until days 14–15 (P < 0.001), and those that succumbed within 10 days showed higher positivity rates in the brain and CSF. All pigs which were positive in the CSF had detectable meningitis. At days 14–15, joint samples from 5 of the remaining 15 pigs tested positive for H. parasuis. Four of these five animals did not show any macroscopic or histological lesions in the joints. In conclusion, collective swabs were the best sample material in acute cases, whereas samples from the joints gave the best results in chronic cases. In this challenge model it was not possible to prove the metaphylactic effect of tulathromycin administered 4 and 7 days prior to infection with H. parasuis