767 research outputs found
Antenna subtraction for gluon scattering at NNLO
We use the antenna subtraction method to isolate the double real radiation
infrared singularities present in gluonic scattering amplitudes at
next-to-next-to-leading order. The antenna subtraction framework has been
successfully applied to the calculation of NNLO corrections to the 3-jet cross
section and related event shape distributions in electron-positron
annihilation. Here we consider processes with two coloured particles in the
initial state, and in particular two-jet production at hadron colliders such as
the Large Hadron Collider (LHC). We construct a subtraction term that describes
the single and double unresolved contributions from the six-gluon tree-level
process using antenna functions with initial state partons and show numerically
that the subtraction term correctly approximates the matrix elements in the
various single and double unresolved configurations.Comment: 71 pages, JHEP3 class; corrected typos, equivalent but more compact
version of eq. (5.12), results unchange
Ecto-nucleoside triphosphate diphosphohydrolase 3 in the ventral and lateral hypothalamic area of female rats: morphological characterization and functional implications
<p>Abstract</p> <p>Background</p> <p>Based on its distribution in the brain, ecto-nucleoside triphosphate diphosphohydrolase 3 (NTPDase3) may play a role in the hypothalamic regulation of homeostatic systems, including feeding, sleep-wake behavior and reproduction. To further characterize the morphological attributes of NTPDase3-immunoreactive (IR) hypothalamic structures in the rat brain, here we investigated: 1.) The cellular and subcellular localization of NTPDase3; 2.) The effects of 17β-estradiol on the expression level of hypothalamic NTPDase3; and 3.) The effects of NTPDase inhibition in hypothalamic synaptosomal preparations.</p> <p>Methods</p> <p>Combined light- and electron microscopic analyses were carried out to characterize the cellular and subcellular localization of NTPDase3-immunoreactivity. The effects of estrogen on hypothalamic NTPDase3 expression was studied by western blot technique. Finally, the effects of NTPDase inhibition on mitochondrial respiration were investigated using a Clark-type oxygen electrode.</p> <p>Results</p> <p>Combined light- and electron microscopic analysis of immunostained hypothalamic slices revealed that NTPDase3-IR is linked to ribosomes and mitochondria, is predominantly present in excitatory axon terminals and in distinct segments of the perikaryal plasma membrane. Immunohistochemical labeling of NTPDase3 and glutamic acid decarboxylase (GAD) indicated that γ-amino-butyric-acid- (GABA) ergic hypothalamic neurons do not express NTPDase3, further suggesting that in the hypothalamus, NTPDase3 is predominantly present in excitatory neurons. We also investigated whether estrogen influences the expression level of NTPDase3 in the ventrobasal and lateral hypothalamus. A single subcutaneous injection of estrogen differentially increased NTPDase3 expression in the medial and lateral parts of the hypothalamus, indicating that this enzyme likely plays region-specific roles in estrogen-dependent hypothalamic regulatory mechanisms. Determination of mitochondrial respiration rates with and without the inhibition of NTPDases confirmed the presence of NTPDases, including NTPDase3 in neuronal mitochondria and showed that blockade of mitochondrial NTPDase functions decreases state 3 mitochondrial respiration rate and total mitochondrial respiratory capacity.</p> <p>Conclusion</p> <p>Altogether, these results suggest the possibility that NTPDases, among them NTPDase3, may play an estrogen-dependent modulatory role in the regulation of intracellular availability of ATP needed for excitatory neuronal functions including neurotransmission.</p
Inference of Well-Typings for Logic Programs with Application to Termination Analysis
This paper develops a method to infer a polymorphic well-typing for a logic program. One of the main motivations is to contribute to a better automation of termination analysis in logic programs, by deriving types from which norms can automatically be constructed. Previous work on type-based termination analysis used either types declared by the user, or automatically generated monomorphic types describing the success set of predicates. Declared types are typically more precise and result in stronger termination conditions than those obtained with inferred types. Our type inference procedure involves solving set constraints generated from the program and derives a well-typing in contrast to a success-set approximation. Experiments show that our automatically inferred well-typings are close to the declared types and thus result in termination conditions that are as good as those obtained with declared types for all our experiments to date. We describe the method, its implementation and experiments with termination analysis based on the inferred types
On the Resolution of Singularities of Multiple Mellin-Barnes Integrals
One of the two existing strategies of resolving singularities of multifold
Mellin-Barnes integrals in the dimensional regularization parameter, or a
parameter of the analytic regularization, is formulated in a modified form. The
corresponding algorithm is implemented as a Mathematica code MBresolve.mComment: LaTeX, 10 page
Antenna subtraction at NNLO with hadronic initial states: real-virtual initial-initial configurations
The antenna subtraction method handles real radiation contributions in higher
order corrections to jet observables. The method is based on antenna functions,
which encapsulate all unresolved radiation between a pair of hard radiator
partons. To apply this method to compute hadron collider observables,
initial-initial antenna functions with both radiators in the initial state are
required. In view of extending the antenna subtraction method to
next-to-next-to-leading order (NNLO) calculations at hadron colliders, we
derive the one-loop initial-initial antenna functions in unintegrated and
integrated form.Comment: 24 page
Double real radiation corrections to production at the LHC: the all-fermion processes
We present the double real radiation corrections to the hadronic
production stemming from partonic processes with fermions only. For this
purpose, we extend the NNLO antenna subtraction formalism developed originally
for the computation of jet observables in annihilation to include the
evaluation of hadronic observables involving a massive pair of particles. In
all partonic processes, we checked the validity of our subtraction terms given
for leading and subleading colour contributions numerically by showing that the
ratio between real radiation matrix elements and subtraction terms approaches
unity in all single and double unresolved configurations.Comment: 68 pages, 9 figure
Antenna subtraction at NNLO with hadronic initial states: double real initial-initial configurations
The antenna subtraction method handles real radiation contributions in higher
order corrections to jet observables. The method is based on antenna functions,
which encapsulate all unresolved radiation between a pair of hard radiator
partons. To apply this method to compute hadron collider observables,
initial-initial antenna functions with both radiators in the initial state are
required in unintegrated and integrated forms. In view of extending the antenna
subtraction method to next-to-next-to-leading order (NNLO) calculations at
hadron colliders, we derive the full set of initial-initial double real
radiation antenna functions in integrated form.Comment: 38 pages; a FORM file with the integrated antennae is included with
this submission. arXiv admin note: text overlap with arXiv:1011.6631,
arXiv:1107.403
Case series: convalescent plasma therapy for patients with COVID-19 and primary antibody deficiency
Patients with primary antibody deficiency are at risk for severe and in many cases for prolonged COVID-19. Convalescent plasma treatment of immunocompromised individuals could be an option especially in countries with limited access to monoclonal antibody therapies. While studies in immunocompetent COVID19 patients have demonstrated only a limited benefit, evidence for the safety, timing, and effectiveness of this treatment in antibody-deficient patients is lacking. Here, we describe 16 cases with primary antibody deficiency treated with convalescent plasma in four medical centers. In our cohort, treatment was associated with a reduction in viral load and improvement of clinical symptoms, even when applied over a week after onset of infection. There were no relevant side effects besides a short-term fever reaction in one patient. Longitudinal full-genome sequencing revealed the emergence of mutations in the viral genome, potentially conferring an antibody escape in one patient with persistent viral RNA shedding upon plasma treatment. However, he resolved the infection after a second course of plasma treatment. Thus, our data suggest a therapeutic benefit of convalescent plasma treatment in patients with primary antibody deficiency even months after infection. While it appears to be safe, PCR follow-up for SARS-CoV-2 is advisable and early re-treatment might be considered in patients with persistent viral shedding
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