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1.
Eur Phys J C Part Fields ; 83(4): 336, 2023.
Article in English | MEDLINE | ID: mdl-37128509

ABSTRACT

We compute next-to-next-to-leading order (NNLO) QCD corrections to neutral vector boson production in association with a charm jet at the LHC. This process is studied in the forward kinematics at s = 13  TeV, which may provide valuable constraints on the intrinsic charm component of the proton. A comparison is performed between fixed order and NLO predictions matched to a parton shower showing mutual compatibility within the respective uncertainties. NNLO corrections typically lead to a reduction of theoretical uncertainties by a factor of two and the perturbative convergence is further improved through the introduction of a theory-inspired constraint on the transverse momentum of the vector boson plus jet system. A comparison between these predictions with data will require an alignment of a flavour-tagging procedure in theory and experiment that is infrared and collinear safe.

2.
Eur Phys J C Part Fields ; 82(10): 930, 2022.
Article in English | MEDLINE | ID: mdl-36277417

ABSTRACT

Fast interpolation-grid frameworks facilitate an efficient and flexible evaluation of higher-order predictions for any choice of parton distribution functions or value of the strong coupling α s . They constitute an essential tool for the extraction of parton distribution functions and Standard Model parameters, as well as studies of the dependence of cross sections on the renormalisation and factorisation scales. The APPLfast project provides a generic interface between the parton-level Monte Carlo generator and both the APPLgrid and the fastNLO libraries for the grid interpolation. The extension of the project to include hadron-hadron collider processes at next-to-next-to-leading order in perturbative QCD is presented, together with an application for jet production at the LHC.

3.
Phys Rev Lett ; 127(7): 072002, 2021 Aug 13.
Article in English | MEDLINE | ID: mdl-34459639

ABSTRACT

We present the first fully differential predictions for the production cross section of a Higgs boson via the gluon fusion mechanism at next-to-next-to-next-to-leading order (N^{3}LO) in QCD perturbation theory. Differential distributions are shown for the two-photon final state produced by the decay of the Higgs boson for a realistic set of fiducial cuts. The N^{3}LO corrections exhibit complex features and are in part larger than the inclusive N^{3}LO corrections to the production cross section. Overall, we observe that the inclusion of the N^{3}LO QCD corrections significantly reduces the perturbative uncertainties and leads to a stabilization of the perturbative expansion.

4.
Transl Anim Sci ; 5(2): txab085, 2021 Apr.
Article in English | MEDLINE | ID: mdl-34222824

ABSTRACT

Promoting feed hygiene with organic acids is an effective method to prevent foodborne illnesses from bacterial infection. The stability and acidification of mash and pelleted feed with sodium buffered formic acid was investigated. The acid product was incorporated to reach total formate inclusion levels of 0, 6, or 12 g/kg for swine nursery feed; 0, 4, or 9 g/kg for swine finishing feed; and 0, 3, or 6 g/kg for broiler grower feed. Samples were analyzed for total formate and pH on d 4, 32, 60, or 88 post-manufacturing. The concentration of formate remained stable across an 88-d period (P < 0.01). Treatment with the formic acid product decreased feed pH with increasing inclusion levels (all P < 0.01). Within each inclusion level of acid and across time, pH tended to increase in pelleted feed and decrease in mash feeds (all P < 0.01); however, these changes were small (0.1 units pH). These data suggest that sodium buffered formic acid can be applied to both mash and pelleted feed to provide continuous acidification over a 3-month period.

5.
J Dairy Sci ; 104(6): 7000-7007, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33865599

ABSTRACT

In the Dutch national surveillance system, an increasing number of reports were received in the summer of 2017 from farmers about unusual behavior of their cows. The cows were grouping during the day in summer in one part of the barn and did not move for several hours, which, according to the farmers, led to reduced food and water intake and lying time and resulted in decreased milk production and increased risk of lameness. Many farmers perceived magnetic fields from, for instance, high-voltage lines, automated milking systems, or solar panels as possible causes for the behavior of their cows. Our aim for the study was to study potential factors such as magnetic fields and other factors such as barn climate and insect burden for adverse grouping behavior of dairy cows in the barn. For each case herd, 2 control herds were selected in the same postal area code. A case was a herd in which cattle grouped at least on 7 occasions in a month for several hours. In a control herd, the cows were in the barn during the same time period as in the matching case herd but did not show adverse grouping behavior. A questionnaire was administered by telephone in 31 case herds and 62 control herds. The questionnaire gathered information on behavior of the cows and potential risk factors. In addition, data on the distance of the herd to high-voltage lines was obtained. From a total of 74 variables, all variables with a P-value ≤0.10 were included in full multivariable logistic regression model. Backward selection was carried out at P ≤ 0.10. The grouping behavior of the cows started in most herds in June, was seen only during the day, and lasted mostly 6 to 8 h, with cows often grouped in the northern part of the barn. Identified risk factors appeared to be recently constructed barns, measured stray voltage in barns, and presence of fans in barns. Given the cross-sectional design of the case-control study, causality for these risk factors leading to adverse behavior of the cows could not be proven. Dissemination of the results to farmers hopefully results in measures that can prevent the unusual grouping behavior of cows.


Subject(s)
Cattle Diseases , Dairying , Animals , Case-Control Studies , Cattle , Cross-Sectional Studies , Female , Milk
6.
Neurol Res Pract ; 2: 13, 2020.
Article in English | MEDLINE | ID: mdl-33324919

ABSTRACT

BACKGROUND: Cerebral small vessel disease (CSVD) is a disorder of brain vasculature that causes various structural changes in the brain parenchyma, and is associated with various clinical symptoms such as cognitive impairment and gait disorders. Structural changes of brain arterioles cannot be visualized with routine imaging techniques in vivo. However, optical coherence tomography (OCT) is thought to be a "window to the brain". Thus, retinal vessel parameters may correlate with CSVD characteristic brain lesions and cerebrospinal fluid biomarkers (CSF) of the neuropathological processes in CSVD like endothelial damage, microglial activation and neuroaxonal damage. METHODS: We applied OCT-based assessment of retinal vessels, magnetic resonance imaging (MRI), and CSF biomarker analysis in a monocentric prospective cohort of 24 patients with sporadic CSVD related stroke and cognitive impairment. MRI lesions were defined according to the STandards for ReportIng Vascular changes on nEuroimaging (STRIVE). Biomarkers were assessed using commercially available ELISA kits. Owing to the unavailability of an age-matched control-group lacking MRI-characteristics of CSVD, we compared the retinal vessel parameters in CSVD patients (73.8 ± 8.5 years) with a younger group of healthy controls (51.0 ± 16.0 years) by using an age- and sex-adjusted multiple linear regression analysis model. RESULTS: Among the parameters measured with OCT, the Wall to Lumen Ratio (WLR) but not Mean Wall Thickness (MWT) of the superior branch of the retinal artery correlated significantly with the volume of white matter hyperintensities on MRI (rs = - 0.5) and with CSF-levels of Chitinase 3 like 1 protein (rs = - 0.6), zona occludens 1 protein (rs = - 0.5) and GFAP (rs = - 0.4). MWT and WLR were higher in CSVD than in controls (28.9 µm vs. 23.9 µm, p = 0.001 and 0.32 vs. 0.25, p = 0.001). CONCLUSIONS: In this exploratory study, WLR correlated with the volume of white matter hyperintensities, and markers of vascular integrity, microglial activation, and neuroaxonal damage in CSVD. Further prospective studies should clarify whether retinal vessel parameters and CSF biomarkers may serve to monitor the natural course and treatment effects in clinical studies on CSVD.

7.
Neurol Res Pract ; 2: 8, 2020.
Article in English | MEDLINE | ID: mdl-33324914

ABSTRACT

INTRODUCTION: Cerebrospinal fluid (CSF) analysis is important for detecting inflammation of the nervous system and the meninges, bleeding in the area of the subarachnoid space that may not be visualized by imaging, and the spread of malignant diseases to the CSF space. In the diagnosis and differential diagnosis of neurodegenerative diseases, the importance of CSF analysis is increasing. Measuring the opening pressure of CSF in idiopathic intracranial hypertension and at spinal tap in normal pressure hydrocephalus constitute diagnostic examination procedures with therapeutic benefits.Recommendations (most important 3-5 recommendations on a glimpse): The indications and contraindications must be checked before lumbar puncture (LP) is performed, and sampling CSF requires the consent of the patient.Puncture with an atraumatic needle is associated with a lower incidence of postpuncture discomfort. The frequency of postpuncture syndrome correlates inversely with age and body mass index, and it is more common in women and patients with a history of headache. The sharp needle is preferably used in older or obese patients, also in punctures expected to be difficult.In order to avoid repeating LP, a sufficient quantity of CSF (at least 10 ml) should be collected. The CSF sample and the serum sample taken at the same time should be sent to a specialized laboratory immediately so that the emergency and basic CSF analysis program can be carried out within 2 h.The indication for LP in anticoagulant therapy should always be decided on an individual basis. The risk of interrupting anticoagulant therapy must be weighed against the increased bleeding risk of LP with anticoagulant therapy.As a quality assurance measure in CSF analysis, it is recommended that all cytological, clinical-chemical, and microbiological findings are combined in an integrated summary report and evaluated by an expert in CSF analysis. CONCLUSIONS: In view of the importance and developments in CSF analysis, the S1 guideline "Lumbar puncture and cerebrospinal fluid analysis" was recently prepared by the German Society for CSF analysis and clinical neurochemistry (DGLN) and published in German in accordance with the guidelines of the AWMF (https://www.awmf.org). /uploads/tx_szleitlinien/030-141l_S1_Lumbalpunktion_und_Liquordiagnostik_2019-08.pdf). The present article is an abridged translation of the above cited guideline. The guideline has been jointly edited by the DGLN and DGN.

8.
Phys Rev Lett ; 125(22): 222002, 2020 Nov 27.
Article in English | MEDLINE | ID: mdl-33315443

ABSTRACT

Precise predictions are provided for the production of a Z boson and a b-jet in hadron-hadron collisions within the framework of perturbative QCD, at O(α_{s}^{3}). To obtain these predictions, we perform the first calculation of a hadronic scattering process involving the direct production of a flavored jet at next-to-next-to-leading-order accuracy in massless QCD and extend techniques to also account for the impact of finite heavy-quark mass effects. The predictions are compared to CMS data obtained in pp collisions at a center-of-mass energy of 8 TeV, which are the most precise data from run I of the LHC for this process, where a good description of the data is achieved. To allow this comparison, we have performed an unfolding of the data, which overcomes the long-standing issue that the experimental and theoretical definitions of jet flavor are incompatible.

9.
Int J Hyg Environ Health ; 230: 113603, 2020 09.
Article in English | MEDLINE | ID: mdl-32882646

ABSTRACT

The aim of this study was to gain more insight in the association between prevalence of diverse acute non-specific symptoms (NSS) and livestock density as a possible risk factor among residents of livestock-dense and non-dense regions, taking into account socio-demographic factors and psychological morbidity. Prevalence of NSS and psychological morbidity were assessed for the year 2017, based on electronic health records from 39 general practices in the Netherlands. The study group consisted of people who lived in rural areas with high numbers of livestock (n = 74093), while the control group included people in rural areas with low numbers of livestock (n = 50139). For a large portion of the study group, exposure estimates (to livestock) were calculated. Multiple logistic multilevel regression analyses were performed. Two methods were used: 1) area comparisons between study and control areas in relation to health problems, and 2) estimates of livestock exposure (to goats, poultry, pigs, and cattle) within the study area. It was found that prevalence of diarrhea, headache, sleep disturbance, respiratory symptoms, and skin problems were higher in the study group. The data suggest that there may be a protective effect of livestock exposure: in general, there was a lower risk of NSS closer to livestock (within the exposure analyses). The study suggests that the previously identified higher risk of respiratory health problems in livestock dense areas might also apply to the prevalence of various other NSS. Longitudinal research taking into account different or more individual and contextual characteristics could possibly elucidate why prevalence of NSS in closer proximity to livestock is lower compared to people who live further away, whilst a more overarching analysis indicated that living in livestock dense areas was associated with more NSS.


Subject(s)
Livestock , Respiratory Tract Diseases , Animals , Cattle , Poultry , Prevalence , Respiratory Tract Diseases/epidemiology , Risk Factors , Swine
10.
Clin Microbiol Infect ; 26(9): 1259.e1-1259.e3, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32470567

ABSTRACT

OBJECTIVES: Legionella is a bacterial species able to cause influenza-like illness (Pontiac fever) or severe pneumonia (Legionnaires disease, LD). We assessed Legionella presence and concentration in composting facilities in The Netherlands. METHODS: A total of 142 samples from 23 green waste composting facilities were screened for Legionella DNA using qPCR. RESULTS: Of 142 samples, Legionella spp. DNA was detected in 97 (68%), and the subspecies L. pneumophila and L. longbeachae in 33 (23%) and one (0.7%) samples, respectively. Legionella was observed in samples from all composting facilities. The concentration of Legionella spp. DNA ranged from 103 to 105 genomic units (GU)/gram. Compost temperature was negatively correlated with the presence (odds ratio 0.67, 95% CI 0.50-0.92 per 10 degrees increase) and concentration (geometric mean ratio 0.90, 95% CI 0.83-0.97 per 10 degrees) of Legionella spp. Average humidity in the week prior to sampling was negatively correlated with the L. pneumophila concentration (geometric mean ratio 0.73, 95% CI 0.56-0.96 per increase in 10% of humidity). DISCUSSION: This study suggests that composting facilities can be regarded as reservoirs of Legionella in The Netherlands, but additional studies should target if such facilities represent a human health risk.


Subject(s)
Composting , Legionella/physiology , Soil Microbiology , DNA, Bacterial/isolation & purification , Legionella/genetics , Netherlands , Waste Disposal Facilities
11.
Eur Phys J C Part Fields ; 79(10): 845, 2019.
Article in English | MEDLINE | ID: mdl-31807114

ABSTRACT

The extension of interpolation-grid frameworks for perturbative QCD calculations at next-to-next-to-leading order (NNLO) is presented for deep inelastic scattering (DIS) processes. A fast and flexible evaluation of higher-order predictions for any a posteriori choice of parton distribution functions (PDFs) or value of the strong coupling constant is essential in iterative fitting procedures to extract PDFs and Standard Model parameters as well as for a detailed study of the scale dependence. The APPLfast project, described here, provides a generic interface between the parton-level Monte Carlo program NNLOjet and both the APPLgrid and fastNLO libraries for the production of interpolation grids at NNLO accuracy. Details of the interface for DIS processes are presented together with the required interpolation grids at NNLO, which are made available. They cover numerous inclusive jet measurements by the H1 and ZEUS experiments at HERA. An extraction of the strong coupling constant is performed as an application of the use of such grids and a best-fit value of α s ( M Z ) = 0.1170 ( 15 ) exp ( 25 ) th is obtained using the HERA inclusive jet cross section data.

12.
Phys Rev Lett ; 123(10): 102001, 2019 Sep 06.
Article in English | MEDLINE | ID: mdl-31573318

ABSTRACT

The measurement of the triple-differential dijet production cross section as a function of the average transverse momentum p_{T,avg}, half the rapidity separation y^{*}, and the boost y_{b} of the two leading jets in the event enables a kinematical scan of the underlying parton momentum distributions. We compute for the first time the second-order perturbative QCD corrections to this triple-differential dijet cross section, at leading color in all partonic channels, thereby enabling precision studies with LHC dijet data. A detailed comparison with experimental CMS 8 TeV data is performed, demonstrating how the shape of this differential cross section probes the parton densities in different kinematical ranges.

13.
Eur Phys J C Part Fields ; 79(6): 526, 2019.
Article in English | MEDLINE | ID: mdl-31303858

ABSTRACT

Final states with a vector boson and a hadronic jet allow one to infer the Born-level kinematics of the underlying hard scattering process, thereby probing the partonic structure of the colliding protons. At forward rapidities, the parton collisions are highly asymmetric and resolve the parton distributions at very large or very small momentum fractions, where they are less well constrained by other processes. Using theory predictions accurate to next-to-next-to-leading order (NNLO) in QCD for both W ± and Z production in association with a jet at large rapidities at the LHC, we perform a detailed phenomenological analysis of recent LHC measurements. The increased theory precision allows us to clearly identify specific kinematical regions where the description of the data is insufficient. By constructing ratios and asymmetries of these cross sections, we aim to identify possible origins of the deviations, and highlight the potential impact of the data on improved determinations of parton distributions.

14.
Sci Rep ; 9(1): 8433, 2019 Jun 05.
Article in English | MEDLINE | ID: mdl-31164658

ABSTRACT

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

15.
Eur Phys J C Part Fields ; 79(12): 1022, 2019.
Article in English | MEDLINE | ID: mdl-31903046

ABSTRACT

We compute the next-to-next-to-leading order (NNLO) QCD corrections to event shape distributions and their mean values in deep inelastic lepton-nucleon scattering. The magnitude and shape of the corrections varies considerably between different variables. The corrections reduce the renormalization and factorization scale uncertainty of the predictions. Using a dispersive model to describe non-perturbative power corrections, we compare the NNLO QCD predictions with data from the H1 and ZEUS experiments. The newly derived corrections improve the theory description of the distributions and of their mean values.

16.
Eur Phys J C Part Fields ; 78(7): 538, 2018.
Article in English | MEDLINE | ID: mdl-30393461

ABSTRACT

Hard processes in diffractive deep-inelastic scattering can be described by a factorisation into parton-level subprocesses and diffractive parton distributions. In this framework, cross sections for inclusive dijet production in diffractive deep-inelastic electron-proton scattering (DIS) are computed to next-to-next-to-leading order (NNLO) QCD accuracy and compared to a comprehensive selection of data. Predictions for the total cross sections, 40 single-differential and four double-differential distributions for six measurements at HERA by the H1 and ZEUS collaborations are calculated. In the studied kinematical range, the NNLO corrections are found to be sizeable and positive. The NNLO predictions typically exceed the data, while the kinematical shape of the data is described better at NNLO than at next-to-leading order (NLO). A significant reduction of the scale uncertainty is achieved in comparison to NLO predictions. Our results use the currently available NLO diffractive parton distributions, and the discrepancy in normalisation highlights the need for a consistent determination of these distributions at NNLO accuracy.

17.
Sci Rep ; 8(1): 14798, 2018 10 04.
Article in English | MEDLINE | ID: mdl-30287870

ABSTRACT

While neurofilament light chain (NfL) measurement in serum is a well-established marker of neuroaxonal damage in multiple sclerosis (MS), data on astroglial markers in serum are missing. In our study, glial fibrillary acid protein (GFAP) and NfL were measured in cerebrospinal fluid (CSF) and serum of MS patients and patients with other non-inflammatory neurological diseases (OND) using the Simoa technology. Clinical data like age, gender, expanded disability status scale (EDSS) and MRI findings were correlated to neurochemical markers. We included 80 MS patients: 42 relapsing-remitting MS (RRMS), 38 progressive MS (PMS), as well as 20 OND. Serum GFAP levels were higher in PMS compared to RRMS and OND (p < 0.001, p = 0.02 respectively). Serum GFAP levels correlated with disease severity in the whole MS group and PMS (Spearman-rho = 0.5, p < 0.001 in both groups). Serum GFAP correlated with serum NfL in PMS patients (Spearman-rho = 0.4, p = 0.01). Levels of serum GFAP were higher with increasing MRI-lesion count (p = 0.01). in summary, we report elevated levels of GFAP in the serum of MS patients. Since serum levels of GFAP correlate with the clinical severity scores and MRI lesion count, especially in PMS patients, it might be a suitable disease progression marker.


Subject(s)
Biomarkers/blood , Glial Fibrillary Acidic Protein/blood , Multiple Sclerosis/diagnosis , Serum/chemistry , Adult , Biomarkers/cerebrospinal fluid , Cerebrospinal Fluid/chemistry , Glial Fibrillary Acidic Protein/cerebrospinal fluid , Humans , Middle Aged , Neurofilament Proteins/blood , Neurofilament Proteins/cerebrospinal fluid , Young Adult
18.
Phys Rev Lett ; 120(12): 122001, 2018 Mar 23.
Article in English | MEDLINE | ID: mdl-29694069

ABSTRACT

The transverse momentum spectra of weak gauge bosons and their ratios probe the underlying dynamics and are crucial in testing our understanding of the standard model. They are an essential ingredient in precision measurements, such as the W boson mass extraction. To fully exploit the potential of the LHC data, we compute the second-order [next-to-next-to-leading-order (NNLO)] QCD corrections to the inclusive-p_{T}^{W} spectrum as well as to the ratios of spectra for W^{-}/W^{+} and Z/W. We find that the inclusion of NNLO QCD corrections considerably improves the theoretical description of the experimental CMS data and results in a substantial reduction of the residual scale uncertainties.

19.
J Neuroinflammation ; 15(1): 88, 2018 Mar 19.
Article in English | MEDLINE | ID: mdl-29554927

ABSTRACT

BACKGROUND: Antibodies to human full-length myelin oligodendrocyte glycoprotein (MOG-IgG) as detected by new-generation cell-based assays have recently been described in patients presenting with acute demyelinating disease of the central nervous system, including patients previously diagnosed with multiple sclerosis (MS). However, only limited data are available on the relevance of MOG-IgG testing in patients with chronic progressive demyelinating disease. It is unclear if patients with primary progressive MS (PPMS) or secondary progressive MS (SPMS) should routinely be tested for MOG-IgG. OBJECTIVE: To evaluate the frequency of MOG-IgG among patients classified as having PPMS or SPMS based on current diagnostic criteria. METHODS: For this purpose, we retrospectively tested serum samples of 200 patients with PPMS or SPMS for MOG-IgG using cell-based assays. In addition, we performed a review of the entire English language literature on MOG-IgG published between 2011 and 2017. RESULTS: None of 139 PPMS and 61 SPMS patients tested was positive for MOG-IgG. Based on a review of the literature, we identified 35 further MOG-IgG tests in patients with PPMS and 55 in patients with SPMS; the only reportedly positive sample was positive just at threshold level and was tested in a non-IgG-specific assay. In total, a single borderline positive result was observed among 290 tests. CONCLUSION: Our data suggest that MOG-IgG is absent or extremely rare among patients with PPMS or SPMS. Routine screening of patients with typical PPMS/SPMS for MOG-IgG seems not to be justified.


Subject(s)
Immunoglobulin G/blood , Multiple Sclerosis, Chronic Progressive/immunology , Multiple Sclerosis, Chronic Progressive/metabolism , Myelin-Oligodendrocyte Glycoprotein/immunology , Adolescent , Adult , Aged , Cohort Studies , Databases, Bibliographic , Female , HEK293 Cells , Humans , Male , Middle Aged , Transfection , Young Adult
20.
Magn Reson Med ; 79(2): 1083-1089, 2018 02.
Article in English | MEDLINE | ID: mdl-28444812

ABSTRACT

PURPOSE: Based on a previous case report of menometrorrhagia (prolonged/excessive uterine bleeding, occurring at irregular and/or frequent intervals) in MRI workers with intrauterine devices (IUDs), it was evaluated whether this association could be confirmed. METHODS: A survey was performed among 381 female radiographers registered with their national association. Logistic regression was used to analyze associations of abnormal uterine bleeding with the frequency of working with MRI scanners, presence near the scanner/in the scanner room during image acquisition, and with scanner strength or type. RESULTS: A total of 68 women reported using IUDs, and 72 reported abnormal uterine bleeding. Compared with unexposed women not using IUDs, the odds ratio in women with IUDs working with MRI scanners was 2.09 (95% confidence interval 0.83-3.66). Associations were stronger if women working with MRI reported being present during image acquisition (odds ratio 3.43, 95% CI 1.26-9.34). Associations with scanner strength or type were not consistent. CONCLUSIONS: Radiographers using IUDs who are occupationally exposed to stray fields from MRI scanners report abnormal uterine bleeding more often than their co-workers without an IUD, or nonexposed co-workers with an IUD. In particular, radiographers present inside the scanner room during image acquisition showed an increased risk. Magn Reson Med 79:1083-1089, 2018. © 2017 International Society for Magnetic Resonance in Medicine.


Subject(s)
Health Personnel/statistics & numerical data , Intrauterine Devices/statistics & numerical data , Magnetic Resonance Imaging/adverse effects , Occupational Exposure , Uterine Hemorrhage/epidemiology , Adult , Cross-Sectional Studies , Female , Humans , Middle Aged , Occupational Exposure/analysis , Occupational Exposure/statistics & numerical data
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