Local analytic sector subtraction at NNLO Magnea, L.; Maina, E.; Pelliccioli, G. ...
The journal of high energy physics,
12/2018, Letnik:
2018, Številka:
12
Journal Article
Recenzirano
Odprti dostop
A
bstract
We present a new method for the local subtraction of infrared divergences at next-to-next-to-leading order (NNLO) in QCD, for generic infrared-safe observables. Our method attempts to ...conjugate the minimal local counterterm structure arising from a sector partition of the radiation phase space with the simplifications following from analytic integration of the counterterms. In this first implementation, the method applies to final-state massless particles. We show how our method compactly organises infrared subtraction at NLO, we deduce in detail the general structure of the subtraction terms at NNLO, and we provide a proof of principle with a complete application to a simple process at NNLO.
A
bstract
Isolating the scattering of longitudinal weak bosons at the LHC is an important tool to probe the ElectroWeak Symmetry Breaking mechanism. Separating polarizations of
W
and
Z
bosons is ...complicated, because of non resonant contributions and interference effects. Additional care is necessary when considering
Z
bosons, due to the γ
/Z
mixing in the coupling to charged leptons. We propose a method to define polarized signals in
ZZ
and
W
+
Z
scattering at the LHC, which relies on the separation of weak boson polarizations at the amplitude level in Monte Carlo simulations. After validation in the absence of lepton cuts, we investigate how polarized distributions are affected by a realistic set of kinematic cuts (and neutrino reconstruction, when needed). The total and differential polarized cross sections computed at the amplitude level are well defined, and their sum reproduces the full results, up to non negligible but computable interference effects which should be included in experimental analyses. We show that polarized cross sections computed using the reweighting method are inaccurate, particularly at large energies. We also present two procedures which address the model independent extraction of polarized components from LHC data, using Standard Model angular distribution templates.
Factorisation and subtraction beyond NLO Magnea, L.; Maina, E.; Pelliccioli, G. ...
The journal of high energy physics,
12/2018, Letnik:
2018, Številka:
12
Journal Article
Recenzirano
Odprti dostop
A
bstract
We provide a general method to construct local infrared subtraction counterterms for unresolved radiative contributions to differential cross sections, to any order in perturbation theory. ...We start from the factorised structure of virtual corrections to scattering amplitudes, where soft and collinear divergences are organised in gauge-invariant matrix elements of fields and Wilson lines, and we define radiative eikonal form factors and jet functions which are fully differential in the radiation phase space, and can be shown to cancel virtual poles upon integration by using completeness relations and general theorems on the cancellation of infrared singularities. Our method reproduces known results at NLO and NNLO, and yields substantial simplifications in the organisation of the subtraction procedure, which will help in the construction of efficient subtraction algorithms at higher orders.
There is little agreement on the most effective and safest treatment for feline demodicosis. Protocols generally consist of long‐lasting therapy courses based on rinses, subcutaneous injections, oral ...drug administration or repeated spot‐on formulation and the efficacy of most of these is poorly documented. Many of these products have also been associated with adverse effects and may be difficult to administer in cats, leading to poor owner compliance and treatment failure. This case report describes the successful use of fluralaner in treating a generalised form of demodicosis caused by Demodex cati in an adult cat that was probably triggered by chronic glucocorticoid administration. After a single oral dose of 28 mg/kg fluralaner, negative skin scrapings were obtained within one month and clinical cure within two months. No side effects were observed. Larger studies are needed to evaluate the efficacy of fluralaner in treating feline generalised demodicosis.
•The rate of viral suppression in patients on cART remains below the UNAIDS target of 90% by 2020.•Durable viral suppression noted in this study is a sign that the UN’s 2030 objective of controlling ...the risk of HIV transmission could be achieved.•The finding of high viral rebound rate in individuals on ART in this study has implication for HIV management.•AZT/3TC/NVP, TDF/3TC/EFV or D4T/3TC/EFV were associated with viral rebound in this cohort, suggesting ART resistance.
Limited data are available on the incidence and factors associated with viral rebound following viral suppression among HIV-infected individuals taking antiretroviral therapy (ART) in Kenya. Furthermore, the durability of viral suppression among HIV individuals taking ART is unknown. Information on incidence rates and factors associated with HIV viral load rebound and the durability of viral suppression (undetectable HIV copies in plasma) among HIV-infected individuals taking ART, will help improve the long-term management of HIV-infected individuals and explore approaches to long-term HIV remission or complete cure.
The objectives of this study were to investigate the incidence rates of viral rebound following viral suppression, factors associated with viral rebound, and the durability of viral suppression among HIV-infected individuals on ART from Kilifi, Meru, and Nakuru counties in Kenya.
This was a retrospective study involving 600 HIV-infected individuals taking combination ART (cART) and enrolled in comprehensive care centers (CCCs) at Malindi Sub-county Hospital, Nakuru Level 5 Hospital, and Meru Level 5 Hospital in Kenya. The medical files were inspected and medical history records abstracted for the selected participants. Participant laboratory data including HIV viral loads, types and history of ART, and treatment history of any opportunistic infections were abstracted using an abstraction checklist. Participants were grouped into those who achieved HIV viral suppression, with viral loads lower than the detection limit (LDL) (viral suppression), and those who experienced one or more detectable viral load measurements >40 copies/ml following the initial LDL (viral rebound). Durable viral suppression was defined as all viral load values at LDL over the 2-year period (2017–2019). Univariate and multivariate Poisson regression analyses were performed to assess the rates of viral rebound, as well as to investigate factors associated with it.
Out of 549 HIV-positive patients, 324/549 (59%) achieved HIV viral suppression (Meru 159/194 (82%), Nakuru 21/178 (12%), and Malindi 144/177 (81%)). The overall viral rebound rate was 41%, with site-specific viral rebound of 88.2%, 18.6%, and 18.0% in Nakuru, Malindi, and Meru, respectively. There was an overall rate of first viral rebound of 3.9 (95% confidence interval (CI) 6.9–14.4), 0.7 (95% CI 0.5–1.0), and 0.89 (95% CI 0.64–1.24) per 100 person-months in Nakuru, Malindi, and Meru, respectively. Good ART adherence (p = 0.0002), widow status (p = 0.0062), and World Health Organization (WHO) stage I (p = 0.0002) were associated with viral suppression, while poor ART adherence (p < 0.0001), WHO stage II (p = 0.0024), and duration on ART of 36 months (p = 0.0350) were associated with viral rebound.
The rate of viral suppression in patients on cART in the CCCs fell short of the WHO target. However, the study provides proof of evidence of undetectable viral load levels for more than 2 years, a sign that the United Nation’s 2030 objective of controlling the risk of HIV transmission could be achieved.
Psychotic illness is strongly associated with the maternal uniparental disomy (mUPD) genetic subtype of Prader-Willi syndrome (PWS), but not the deletion subtype (delPWS). This study investigates the ...clinical features of psychiatric illness associated with PWS. We consider possible genetic and other mechanisms that may be responsible for the development of psychotic illness, predominantly in those with mUPD.
The study sample comprised 119 individuals with genetically confirmed PWS, of whom 46 had a history of psychiatric illness. A detailed clinical and family psychiatric history was obtained from these 46 using the PAS-ADD, OPCRIT, Family History and Life Events Questionnaires.
Individuals with mUPD had a higher rate of psychiatric illness than those with delPWS (22/34 v. 24/85, p<0.001). The profile of psychiatric illness in both genetic subtypes resembled an atypical affective disorder with or without psychotic symptoms. Those with delPWS were more likely to have developed a non-psychotic depressive illness (p=0.005) and those with mUPD a bipolar disorder with psychotic symptoms (p=0.00005). Individuals with delPWS and psychotic illness had an increased family history of affective disorder. This was confined exclusively to their mothers.
Psychiatric illness in PWS is predominately affective with atypical features. The prevalence and possibly the severity of illness are greater in those with mUPD. We present a 'two-hit' hypothesis, involving imprinted genes on chromosome 15, for the development of affective psychosis in people with PWS, regardless of genetic subtype.
ABSTRACT
We present MeerKAT Absorption Line Survey (MALS) observations of the H i gas in the Klemola 31 galaxy group (z = 0.029), located along the line of sight to the radio-loud quasar PKS 2020−370 ...(z = 1.048). Four galaxies of the group are detected in H i emission, and H i absorption is also detected in front of PKS 2020−370 in Klemola 31A. The emission and absorption are somewhat compensating on the line of sight of the quasar, and the derived column density of the absorption appears underestimated, with respect to the neighbouring emission. A symmetric tilted-ring model of Klemola 31A, assuming the absorbing gas in regular rotation in the plane, yields a rather high spin temperature of 530 K. An alternative interpretation is that the absorbing gas is extra-planar, which will also account for its non-circular motion. The Na i/Ca ii ratio also suggests that the absorbing gas is unrelated to cold H i disc. Two of the galaxies in the Klemola group are interacting with a small companion, and reveal typical tidal tails, and velocity perturbations. Only one of the galaxies, ESO 400−13, reveals a strong H i deficiency, and a characteristic ram-pressure stripping, with a total asymmetry in the distribution of its gas. Since a small galaxy group as Klemola 31 is not expected to host a dense intra-group gas, this galaxy must be crossing the group at a very high velocity, mostly in the sky plane.
This study assessed the level of heavy metal in roadside dust and PM
2.5
mass concentrations along Thika superhighway in Kenya. Thika superhighway is one of the busiest roads in Kenya, linking Thika ...town with Nairobi. Triplicate road dust samples collected from 12 locations were analysed for lead (Pb), chromium (Cr), cadmium (Cd), nickel (Ni), zinc (Zn), and copper (Cu) using atomic absorption spectrophotometry (AAS). PM
2.5
samples were collected on pre-weighed Teflon filters using a BGI personal sampler and the filters were then reweighed. The ranges of metal concentrations were 39–101 μg/g for Cu, 95–262 μg/g for Zn, 9–28 μg/g for Cd, 14–24 μg/g for Ni, 13–30 μg/g for Cr, and 20–80 μg/g for Pb. The concentrations of heavy metals were generally highly correlated, indicating a common anthropogenic source of the pollutants. The results showed that the majority of the measured heavy metals were above the background concentration, and in particular, Cd, Pb, and Zn levels indicated moderate to high contamination. Though not directly comparable due to different sampling timeframes (8 h in this study and 24 h for guideline values), PM
2.5
for all sites exceeds the daily WHO PM
2.5
guidelines of 25 μg/m
3
. This poses a health risk to people using and working close to Thika superhighway, for example, local residents, traffic police, street vendors, and people operating small businesses. PM
2.5
levels were higher for sites closer to Nairobi which could be attributed to increased vehicular traffic towards Nairobi from Thika. This study provides some evidence of the air pollution problem arising from vehicular traffic in developing parts of the world and gives an indication of the potential health impacts. It also highlights the need for source apportionment studies to determine contributions of anthropogenic emissions to air pollution, as well as long-term sampling studies that can be used to fully understand spatiotemporal patterns in air pollution within developing regions.
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