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Higgs production in association with off-shell top-antitop pairs at NLO EW and QCD at the LHC
(2017)
We present NLO electroweak corrections to Higgs production in association with off-shell top-antitop quark pairs. The full process pp → e +νeµ −ν¯µbb¯H is considered, and hence all interference, off-shell, and non-resonant contributions are taken into account.
The electroweak corrections turn out to be below one per cent for the integrated cross section but can exceed 10% in certain phase-space regions. In addition to its phenomenological relevance, the computation constitutes a major technical achievement as the full NLO virtual corrections involving up to 9-point functions have been computed exactly. The results of the full computation are supported by two calculations in the double-pole approximation. These also allow to infer the effect of off-shell contributions and emphasise their importance especially for the run II of the LHC. Finally, we present combined predictions featuring both NLO electroweak and QCD corrections in a common set-up that will help the experimental collaborations in their quest of precisely measuring the aforementioned process.
We present the computer code RECOLA2 along with the first NLO electroweak corrections to Higgs production in vector-boson fusion and updated results for Higgs strahlung in the Two-Higgs-Doublet Model and Higgs-Singlet extension of the Standard Model. A fully automated procedure for the generation of tree-level and one-loop matrix elements in general models, including renormalization, is presented. We discuss the application of the Background-Field Method to the extended models. Numerical results for NLO electroweak cross sections are presented for different renormalization schemes in the Two-Higgs-Doublet Model and the Higgs-Singlet extension of the Standard Model. Finally, we present distributions for the production of a heavy Higgs boson.
Introduction.
Tropheryma whipplei is the causative agent of Whipple’s disease. Gastrointestinal and lymphatic tissues are affected in the majority of cases, resulting in diarrhoea, malabsorption and fever. Here, we report a rare case of ocular manifestation in a patient lacking the typical Whipple symptoms.
Case presentation.
A 74-year-old Caucasian female presented with blurred vision in the right eye over a period of 1–2 months, accompanied by stinging pain and conjunctival hyperaemia for the last 2 days. Upon admission, visual acuity was hand motion in the affected eye. Ophthalmological examination showed typical signs of intraocular inflammation. Diagnostic and therapeutic pars plana vitrectomy including vitreous biopsy and intravitreal instillation of vancomycin and amikacin was performed within hours of initial presentation. Both microscopic analysis and microbial cultures of the vitreous biopsy remained negative for bacteria and fungi. The postoperative antibiotic regime included intravenous administration of ceftriaxone in combination with topical tobramycin and ofloxacin. Due to the empirical therapy the inflammation ceased and the patient was discharged after 5 days with cefpodoxime orally and local antibiotic and steroidal therapy. Meanwhile, the vitreous body had undergone testing by PCR for the eubacterial 16S rRNA gene, which was found to be positive. Analysis of the PCR product revealed a specific sequence of T. whipplei.
Conclusion.
In our patient, endophthalmitis was the first and only symptom of Morbus Whipple, while most patients with Whipple’s disease suffer from severe gastrointestinal symptoms. 16S rDNA PCR should be considered for any intraocular infection when microscopy and standard culture methods remain negative.
Spontaneous Ca\(^{2+}\) transients and actin dynamics in primary motoneurons correspond to cellular differentiation such as axon elongation and growth cone formation. Brain-derived neurotrophic factor (BDNF) and its receptor trkB support both motoneuron survival and synaptic differentiation. However, in motoneurons effects of BDNF/trkB signaling on spontaneous Ca\(^{2+}\) influx and actin dynamics at axonal growth cones are not fully unraveled. In our study we addressed the question how neurotrophic factor signaling corresponds to cell autonomous excitability and growth cone formation. Primary motoneurons from mouse embryos were cultured on the synapse specific, β2-chain containing laminin isoform (221) regulating axon elongation through spontaneous Ca\(^{2+}\) transients that are in turn induced by enhanced clustering of N-type specific voltage-gated Ca\(^{2+}\) channels (Ca\(_{v}\)2.2) in axonal growth cones. TrkB-deficient (trkBTK\(^{-/-}\)) mouse motoneurons which express no full-length trkB receptor and wildtype motoneurons cultured without BDNF exhibited reduced spontaneous Ca\(^{2+}\) transients that corresponded to altered axon elongation and defects in growth cone morphology which was accompanied by changes in the local actin cytoskeleton. Vice versa, the acute application of BDNF resulted in the induction of spontaneous Ca\(^{2+}\) transients and Ca\(_{v}\)2.2 clustering in motor growth cones, as well as the activation of trkB downstream signaling cascades which promoted the stabilization of β-actin via the LIM kinase pathway and phosphorylation of profilin at Tyr129. Finally, we identified a mutual regulation of neuronal excitability and actin dynamics in axonal growth cones of embryonic motoneurons cultured on laminin-221/211. Impaired excitability resulted in dysregulated axon extension and local actin cytoskeleton, whereas upon β-actin knockdown Ca\(_{v}\)2.2 clustering was affected. We conclude from our data that in embryonic motoneurons BDNF/trkB signaling contributes to axon elongation and growth cone formation through changes in the local actin cytoskeleton accompanied by increased Ca\(_{v}\)2.2 clustering and local calcium transients. These findings may help to explore cellular mechanisms which might be dysregulated during maturation of embryonic motoneurons leading to motoneuron disease.
Eu\(^{3+}\)-modified carbon dots (C-dots), 3–5 nm in diameter, were prepared, functionalized, and stabilized via a one-pot polyol synthesis. The role of Eu\(^{2+}\)/Eu\(^{3+}\), the influence of O\(_2\) (oxidation) and H\(_2\)O (hydrolysis), as well as the impact of the heating procedure (conventional resistance heating and microwave (MW) heating) were explored. With the reducing conditions of the polyol at the elevated temperature of synthesis (200–230 °C), first of all, Eu\(^{2+}\) was obtained resulting in the blue emission of the C-dots. Subsequent to O\(_2\)-driven oxidation, Eu\(^{3+}\)-modified, red-emitting C-dots were realized. However, the Eu\(^{3+}\) emission is rapidly quenched by water for C-dots prepared via conventional resistance heating. In contrast to the hydroxyl functionalization of conventionally-heated C-dots, MW-heating results in a carboxylate functionalization of the C-dots. Carboxylate-coordinated Eu\(^{3+}\), however, turned out as highly stable even in water. Based on this fundamental understanding of synthesis and material, in sum, a one-pot polyol approach is established that results in H\(_2\)O-dispersable C-dots with intense red Eu\(^{3+}\)-line-type emission.
Der Atlantische Wildkohl (Brassica oleracea L. subsp. oleracea) wächst auf den Küstenfelsen des Atlantiks und der Nordsee zwischen Nord-Spanien, Schottland und der Nordseeinsel Helgoland. 2001 wurde auch ein Vorkommen des Wildkohls an den Kreidefelsen der Ostseeinsel Rügen nachgewiesen, das aus ungefähr 50 Individuen besteht. Die Pflanzen unterscheiden sich phänotypisch nicht von Wildpflanzen der Atlantikküsten. Da alle verbreiteten Kultursorten des Gemüsekohls genetisch sehr eng mit dem Atlantischen Kohl verwandt sind, vom dem sie höchstwahrscheinlich abstammen, wird die Frage erörtert, ob eine spontane Rückverwandlung (Rückkreuzung) von in die Natur entwichenen Kultursorten in den Wildkohl-Phänotyp möglich ist. Dieses wird als wenig wahrscheinlich angesehen. Dagegen ist Introgression zwischen Kultursorten und Wildsorten gut belegt. Die Frage nach einer möglichen Hybridisierung von Grünkohl mit Pflanzen vom Wildkohlphänotyp oder mit anderen Kultursorten an der Kreideküste der dänischen Ostseeinsel Seeland wird anhand eigener Beobachtungen erörtert. Die dortige Population besteht offensichtlich aus verwilderten Kulturkohlhybriden, die sich deutlich von den Wildpflanzen Rügens unterscheiden. Das neue Vorkommen des Atlantischen Wildkohls in der westlichen Ostsee kann im Zusammenhang mit der Ostausbreitung anderer atlantischer Sippen im Rahmen des Klimawandels gesehen werden.
The genus Ficaria is now considered to comprize eight Eurasian species. The most widespread European species is the tetraploid F. verna Huds. The present study provides evidence for the existence of two main lineages of F. verna that differ considerably in their genomic size by about 3 pg. A Western F. verna lineage west of river Rhine displays a mean genome size (2C-value) of 34.2 pg and is almost precisely codistributed with the diploid F. ambigua Boreau (20 pg) north of the Mediterranean. The remaining part of Europe appears to be occupied by the Eastern F. verna lineage solely (mean genome size of 31.3 pg) which codistributes in South-Eastern Europe with the diploid F. calthifolia Rchb. (15 pg). There is little overlap at the boundary of Western and Eastern F. verna lineages with the occurrence of a separate intermediate group in the Netherlands (mean genomic size of 33.2 pg) that appears to result from hybridization of both lineages. On the basis of these observations and further considerations we propose development of F. ambigua and F. calthifolia south of the Alps with subsequent divergence to populate their current Western and Eastern European ranges, respectively. The Western F. verna lineage is proposed to originate from autotetraploidization of F. ambigua (precursor) with moderate genomic downsizing and the Eastern F. verna lineage from auto¬tetraploidization of F. calthifolia (precursor).
Rubus viridilucidus Drenckhahn ist eine tetraploide Brombeerart (2n=28) aus der Sektion Corylifolii, Serie Subcanescentes mit einem Genomgewicht (2C-Wert) von 1,49 pg, das dem Genomgewicht verwandter Sippen der Serie Subcanescentes wie R. scabrosus, R. fasciculatiformis und R. fasciculatus (1,52–1,54 pg) aus Unterfranken entspricht. Charakteristische Merkmale sind 3–4(5)-zählige Blätter mit herab gekrümmten rundlichen bis breit obovaten Endblättchen und breitovalen Seitenblättchen, die eine völlig unbehaarte, lichtgrüne, mattglänzende Blattoberfläche besitzen mit kontrastierender hell grünlich-grauer, samtig behaarter Blattunterseite. Die überwiegend rundlichen bis stumpf kantigen, lichtgrünen bis rötlich überlaufenen Schösslinge sind unbehaart und spärlich mit kurzen (<4mm) nadelförmigen Stacheln und wenigen Stieldrüsen besetzt. R. viridilucidus entwickelt zusätzlich zu den Blütenzweigen der zweijährigen Schösslinge (Ausbreitungsschösslinge) einen besonderen blühenden 0,8 bis 1,6 m langen Schösslingstyp aus, den Rispenschössling, der direkt aus dem Wurzelstock entspringt und terminal in eine Blütenrispe ausläuft. Bei R. viridilucidus sind zwei verschiedene Typen von Rispenschösslingen ausgebildet. Die Sippe wächst bevorzugt auf gestörten Flächen wie Brachen, Straßenrändern, Lagerplätzen, Weinbergrändern und kann sich mit 1–2 m jährlichem Zuwachs (Satellitenbildauswertung, Vermessungen vor Ort) schnell ausbreiten. Die bekannt gewordenen Fundstellen erstrecken sich vom nördlichen Baden-Württemberg bis in den nördlichsten Teil von Bayern (Rhön).
Social immunity is a key factor for honeybee health, including behavioral defense strategies such as the collective use of antimicrobial plant resins (propolis). While laboratory data repeatedly show significant propolis effects, field data are scarce, especially at the colony level. Here, we investigated whether propolis, as naturally deposited in the nests, can protect honeybees against ectoparasitic mites Varroa destructor and associated viruses, which are currently considered the most serious biological threat to European honeybee subspecies, Apis mellifera, globally. Propolis intake of 10 field colonies was manipulated by either reducing or adding freshly collected propolis. Mite infestations, titers of deformed wing virus (DWV) and sacbrood virus (SBV), resin intake, as well as colony strength were recorded monthly from July to September 2013. We additionally examined the effect of raw propolis volatiles on mite survival in laboratory assays. Our results showed no significant effects of adding or removing propolis on mite survival and infestation levels. However, in relation to V. destructor, DWV titers increased significantly less in colonies with added propolis than in propolis-removed colonies, whereas SBV titers were similar. Colonies with added propolis were also significantly stronger than propolis-removed colonies. These findings indicate that propolis may interfere with the dynamics of V. destructor-transmitted viruses, thereby further emphasizing the importance of propolis for honeybee health.
The electrodynamics of topological insulators (TIs) is described by modified Maxwell’s equations, which contain additional terms that couple an electric field to a magnetization and a magnetic field to a polarization of the medium, such that the coupling coefficient is quantized in odd multiples of α/4π per surface. Here we report on the observation of this so-called topological magnetoelectric effect. We use monochromatic terahertz (THz) spectroscopy of TI structures equipped with a semitransparent gate to selectively address surface states. In high external magnetic fields, we observe a universal Faraday rotation angle equal to the fine structure constant α=e\(^{2}\)/2E\(_{0}\)hc (in SI units) when a linearly polarized THz radiation of a certain frequency passes through the two surfaces of a strained HgTe 3D TI. These experiments give insight into axion electrodynamics of TIs and may potentially be used for a metrological definition of the three basic physical constants.
Thymus-derived natural Foxp3\(^{+}\) CD4\(^{+}\) regulatory T cells (nTregs) play a key role in maintaining immune tolerance and preventing autoimmune disease. Several studies indicate that dendritic cells (DCs) are critically involved in the maintenance and proliferation of nTregs. However, the mechanisms how DCs manage to keep the peripheral pool at constant levels remain poorly understood. Here, we describe that the NF-κB/Rel family transcription factor RelB controls the frequencies of steady-state migratory DCs (ssmDCs) in peripheral lymph nodes and their numbers control peripheral nTreg homeostasis. DC-specific RelB depletion was investigated in CD11c-Cre × RelB\(^{fl/fl}\) mice (RelB\(^{DCko}\)), which showed normal frequencies of resident DCs in lymph nodes and spleen while the subsets of CD103\(^{-}\) Langerin\(^{-}\) dermal DCs (dDCs) and Langerhans cells but not CD103\(^{+}\) Langerin\(^{+}\) dDC of the ssmDCs in skin-draining lymph nodes were increased. Enhanced frequencies and proliferation rates were also observed for nTregs and a small population of CD4\(^{+}\) CD44\(^{high}\) CD25\(^{low}\) memory-like T cells (Tml). Interestingly, only the Tml but not DCs showed an increase in IL-2-producing capacity in lymph nodes of RelB\(^{DCko}\) mice. Blocking of IL-2 in vivo reduced the frequency of nTregs but increased the Tml frequencies, followed by a recovery of nTregs. Taken together, by employing RelB\(^{DCko}\) mice with increased frequencies of ssmDCs our data indicate a critical role for specific ssmDC subsets for the peripheral nTreg and IL-2\(^{+}\) Tml frequencies during homeostasis.
Der lyrische Triebtäter André Pieyre de Mandiargues Gewalt und Erotik im Gedichtband L’Âge de craie
(2017)
The surrealists are not the only influence on the literary efforts of André Pieyre de Mandiargues – but it’s this influence that makes his oeuvre capable for an analysis based on Freudian theories. This way of an analysis is even more appropriate knowing that two of Mandiargues’ main and favourite themes – the eroticism and the violence – coincide with the Freudian life and destruction drive. Analysing the two poems Les filles des gobes and Les ruines de l’amour from the volume of poems L’Âge de craie, it’s these two paradigms that are clearly recognizable: Mandiargues’ symbolism reveals the duality of the domination by desires.
Blood platelets are produced by large bone marrow (BM) precursor cells, megakaryocytes (MKs), which extend cytoplasmic protrusions (proplatelets) into BM sinusoids. The molecular cues that control MK polarization towards sinusoids and limit transendothelial crossing to proplatelets remain unknown. Here, we show that the small GTPases Cdc42 and RhoA act as a regulatory circuit downstream of the MK-specific mechanoreceptor GPIb to coordinate polarized transendothelial platelet biogenesis. Functional deficiency of either GPIb or Cdc42 impairs transendothelial proplatelet formation. In the absence of RhoA, increased Cdc42 activity and MK hyperpolarization triggers GPIb-dependent transmigration of entire MKs into BM sinusoids. These findings position Cdc42 (go-signal) and RhoA (stop-signal) at the centre of a molecular checkpoint downstream of GPIb that controls transendothelial platelet biogenesis. Our results may open new avenues for the treatment of platelet production disorders and help to explain the thrombocytopenia in patients with Bernard–Soulier syndrome, a bleeding disorder caused by defects in GPIb-IX-V.
Multiple Myeloma (MM) is an incurable hematological malignancy affecting millions of people worldwide. As in all tumor cells both glucose and more recently glutamine have been identified as important for MM cellular metabolism, however there is some dispute as to the role of glutamine in MM cell survival. Here we show that the small molecule inhibitor compound 968 effectively inhibits glutaminase and that this inhibition induces apoptosis in both human multiple myeloma cell lines (HMCLs) and primary patient material. The HMCL U266 which does not express MYC was insensitive to both glutamine removal and compound 968, but ectopic expression of MYC imparted sensitivity. Finally, we show that glutamine depletion is reflected by rapid loss of MYC protein which is independent of MYC transcription and post translational modifications. However, MYC loss is dependent on proteasomal activity, and this loss was paralleled by an equally rapid induction of apoptosis. These findings are in contrast to those of glucose depletion which largely affected rates of proliferation in HMCLs, but had no effects on either MYC expression or viability. Therefore, inhibition of glutaminolysis is effective at inducing apoptosis and thus serves as a possible therapeutic target in MM.
Background
Depression is a common comorbidity in patients with chronic heart failure (HF) and linked to a wider range of symptoms which, in turn, are linked to a decreased health-related quality of life (HRQOL). Treatment of depression might improve HRQOL but detecting depression is difficult due to the symptom overlap between HF and depression. Therefore, clinical guidelines recommend to routinely screen for depression in HF patients. No studies have so far investigated the treatment after getting aware of a depressive symptomatology and its correlation with HRQOL in primary care HF patients. Therefore, we examined the factors linked to depression treatment and those linked to HRQOL in HF patients. We hypothesized that GPs’ awareness of depressive symptomatology was associated with depression treatment and HRQOL in HF patients.
Methods
For this observational study, HF patients were recruited in primary care practices and filled out a questionnaire including PHQ-9 and HADS. A total of 574 patients screened positive for depressive symptomatology. Their GPs were interviewed by phone regarding the patients’ comorbidities and potential depression treatment. Descriptive and regression analysis were performed.
Results
GPs reported various types of depression treatments (including dialogue/counselling by the GP him/herself in 31.8% of the patients). The reported rates differed considerably between GP-reported initiated treatment and patient-reported utilised treatment regarding psychotherapy (16.4% vs. 9.5%) and pharmacotherapy (61.2% vs. 30.3%). The GPs' awareness of depressive symptomatology was significantly associated with the likelihood of receiving pharmacotherapy (OR 2.8; p < 0.001) but not psychotherapy. The patient’s HRQOL was not significantly associated with the GPs' awareness of depression.
Conclusion
GPs should be aware of the gap between GP-initiated and patient-utilised depression treatments in patients with chronic HF, which might lead to an undersupply of depression treatment. It remains to be investigated why GPs’ awareness of depressive symptomatology is not linked to patients’ HRQOL. We hypothesize that GPs are aware of cases with reduced HRQOL (which improves under depression treatment) and unaware of cases whose depression do not significantly impair HRQOL, resulting in comparable levels of HRQOL in both groups. This hypothesis needs to be further investigated.
The orthorhombic rare-earth manganite compounds \(R\)MnO\(_3\) show a global magnetic order for \(T\) < \(T\)\(_N\), and several representatives are multiferroic with a cycloidal spin ground state order for \(T\) < \(T\)\(_c\)\(_y\)\(_c\)\(_l\) < \(T\)\(_N\) \(\approx\) 40 K. We deduce from the temperature dependence of spin–phonon coupling in Raman spectroscopy for a series of \(R\)MnO\(_3\) compounds that their spin order locally persists up to about twice \(T\)\(_N\). Along the same line, our observation of the persistence of the electromagnon in GdMnO\(_3\) up to \(T\) \(\approx\) 100 K is attributed to a local cycloidal spin order for \(T\) > \(T\)\(_c\)\(_y\)\(_c\)\(_l\), in contrast to the hitherto assumed incommensurate sinusoidal phase in the intermediate temperature range. The development of the magnetization pattern can be described in terms of an order–disorder transition at \(T\)\(_c\)\(_y\)\(_c\)\(_l\) within a pseudospin model of localized spin cycloids with opposite chirality.
Interactions between different formative processes are reflected in the internal structure of rock glaciers. Therefore, the detection of subsurface conditions can help to enhance our understanding of landform development. For an assessment of subsurface conditions, we present an analysis of the spatial variability of active layer thickness, ground ice content and frost table topography for two different rock glaciers in the Eastern Swiss Alps by means of quasi-3-D electrical resistivity imaging (ERI). This approach enables an extensive mapping of subsurface structures and a spatial overlay between site-specific surface and subsurface characteristics. At Nair rock glacier, we discovered a gradual descent of the frost table in a downslope direction and a constant decrease of ice content which follows the observed surface topography. This is attributed to ice formation by refreezing meltwater from an embedded snow bank or from a subsurface ice patch which reshapes the permafrost layer. The heterogeneous ground ice distribution at Uertsch rock glacier indicates that multiple processes on different time domains were involved in the development. Resistivity values which represent frozen conditions vary within a wide range and indicate a successive formation which includes several advances, past glacial overrides and creep processes on the rock glacier surface. In combination with the observed topography, quasi-3-D ERI enables us to delimit areas of extensive and compressive flow in close proximity. Excellent data quality was provided by a good coupling of electrodes to the ground in the pebbly material of the investigated rock glaciers. Results show the value of the quasi-3-D ERI approach but advise the application of complementary geophysical methods for interpreting the results.
Within gauge/gravity duality, we consider the local quench-like time evolution obtained by joining two 1+1-dimensional heat baths at different temperatures at time \(t\) = 0. A steady state forms and expands in space. For the 2+1-dimensional gravity dual, we find that the “shockwaves” expanding the steady-state region are of spacelike nature in the bulk despite being null at the boundary. However, they do not transport information. Moreover, by adapting the time-dependent Hubeny-Rangamani-Takayanagi prescription, we holographically calculate the entanglement entropy and also the mutual information for different entangling regions. For general temperatures, we find that the entanglement entropy increase rate satisfies the same bound as in the ‘entanglement tsunami’ setups. For small temperatures of the two baths, we derive an analytical formula for the time dependence of the entanglement entropy. This replaces the entanglement tsunami-like behaviour seen for high temperatures. Finally, we check that strong subadditivity holds in this time-dependent system, as well as further more general entanglement inequalities for five or more regions recently derived for the static case.
We develop the formalism of holographic renormalization to compute two-point functions in a holographic Kondo model. The model describes a (0 + 1)-dimensional impurity spin of a gauged SU(N ) interacting with a (1 + 1)-dimensional, large-N , strongly-coupled Conformal Field Theory (CFT). We describe the impurity using Abrikosov pseudo-fermions, and define an SU(N )-invariant scalar operator O built from a pseudo-fermion and a CFT fermion. At large N the Kondo interaction is of the form O\(^{†}\)O, which is marginally relevant, and generates a Renormalization Group (RG) flow at the impurity. A second-order mean-field phase transition occurs in which O condenses below a critical temperature, leading to the Kondo effect, including screening of the impurity. Via holography, the phase transition is dual to holographic superconductivity in (1 + 1)-dimensional Anti-de Sitter space. At all temperatures, spectral functions of O exhibit a Fano resonance, characteristic of a continuum of states interacting with an isolated resonance. In contrast to Fano resonances observed for example in quantum dots, our continuum and resonance arise from a (0 + 1)-dimensional UV fixed point and RG flow, respectively. In the low-temperature phase, the resonance comes from a pole in the Green’s function of the form −i〈O〉\(^{2}\), which is characteristic of a Kondo resonance.