| 61. |
- Aad, G., et al.
(författare)
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Search for flavour-changing neutral-current couplings between the top quark and the photon with the ATLAS detector at √s=13 TeV
- 2023
-
Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 842
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Tidskriftsartikel (refereegranskat)abstract
- This letter documents a search for flavour-changing neutral currents (FCNCs), which are strongly suppressed in the Standard Model, in events with a photon and a top quark with the ATLAS detector. The analysis uses data collected in pp collisions at √s = 13 TeV during Run 2 of the LHC, corresponding to an integrated luminosity of 139 fb−1. Both FCNC top-quark production and decay are considered. The final state consists of a charged lepton, missing transverse momentum, a b-tagged jet, one high-momentum photon and possibly additional jets. A multiclass deep neural network is used to classify events either as signal in one of the two categories, FCNC production or decay, or as background. No significant excess of events over the background prediction is observed and 95% CL upper limits are placed on the strength of left- and right-handed FCNC interactions. The 95% CL bounds on the branching fractions for the FCNC top-quark decays, estimated (expected) from both top-quark production and decay, are B(t → uγ ) < 0.85 (0.88) × 10−5 and B(t → cγ ) < 4.2 (3.40) × 10−5 for a left-handed tqγ coupling, and B(t → uγ ) < 1.2 (1.20)×10−5 and B(t → cγ ) < 4.5 (3.70)×10−5 for a right-handed coupling.
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| 62. |
- Aad, G., et al.
(författare)
-
Search for heavy long-lived multi-charged particles in the full LHC Run 2 pp collision data at √s=13 TeV using the ATLAS detector
- 2023
-
Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 847
-
Tidskriftsartikel (refereegranskat)abstract
- A search for heavy long-lived multi-charged particles is performed using the ATLAS detector at the LHC. Data collected in 2015-2018 at √s = 13 TeV from pp collisions corresponding to an integrated luminosity of 139 fb−1 are examined. Particles producing anomalously high ionization, consistent with long-lived spin-½ massive particles with electric charges from |q| = 2e to |q| = 7e are searched for. No statistically significant evidence of such particles is observed, and 95% confidence level cross-section upper limits are calculated and interpreted as the lower mass limits for a Drell-Yan plus photon-fusion production mode. The least stringent limit, 1060 GeV, is obtained for |q| = 2e particles, and the most stringent one, 1600 GeV, is for |q| = 6e particles.
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| 63. |
- Aad, G., et al.
(författare)
-
Search for pair-production of vector-like quarks in pp collision events at √s = 13 TeV with at least one leptonically decaying Z boson and a third-generation quark with the ATLAS detector
- 2023
-
Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 843
-
Tidskriftsartikel (refereegranskat)abstract
- A search for the pair-production of vector-like quarks optimized for decays into a Z boson and a third-generation Standard Model quark is presented, using the full Run 2 dataset corresponding to 139 fb−1 of pp collisions at √s = 13 TeV, collected in 2015–2018 with the ATLAS detector at the Large Hadron Collider. The targeted final state is characterized by the presence of a Z boson with high transverse momentum, reconstructed from a pair of same-flavour leptons with opposite-sign charges, as well as by the presence of b-tagged jets and high-transverse-momentum large-radius jets reconstructed from calibrated smaller-radius jets. Events with exactly two or at least three leptons are used, which are further categorized by the presence of boosted W , Z, and Higgs bosons and top quarks. The categorization is performed using a neural-network-based boosted object tagger to enhance the sensitivity to signal relative to the background. No significant excess above the background expectation is observed and exclusion limits at 95% confidence level are set on the masses of the vector-like partners T and B of the top and bottom quarks, respectively. The limits depend on the branching ratio configurations and, in the case of 100% branching ratio for T → Zt and 100% branching ratio for B → Zb, this search sets the most stringent limits to date, allowing mT > 1.60 TeV and mB > 1.42 TeV, respectively.
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| 64. |
- Al-Adili, Lina, et al.
(författare)
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Setting goals with patients at risk of malnutrition : A focus group study with clinical dietitians
- 2022
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Ingår i: Patient Education and Counseling. - : Elsevier. - 0738-3991 .- 1873-5134. ; 105:7, s. 2103-2109
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: Setting goals collaboratively with patients is a key aspect in shared decision-making (SDM) in malnutrition interventions. The aim, therefore, was to gain an understanding of clinical dietitians' reflections regarding the process of goal-setting with patients at risk of malnutrition.Methods: Six semi-structured audio-recorded focus group discussions were held with registered dietitians (n = 29) from primary healthcare and hospitals in Sweden. Focus group transcripts were analysed thematically to find patterns in the data and identify themes.Results: Dietitians expressed striving to explore patients' narratives, capabilities, and resources before deciding on goals. They described different strategies in counseling patients and a lack of patient participation in the goal setting. They emphasized the difficulties of setting feasible goals due to discrepancies between their clinically oriented goals and patients' personal goals.Conclusion: Findings highlight a gap in the process of setting goals for patients at risk of malnutrition, where patients' participation was lacking. Education in SDM, and strategies and tools to support dietitians in involving patients in goal-setting, are required to bridge the gap and promote person-centeredness. Practice implications: Findings may be further used to develop tools and strategies, and design studies on the implementation of and education in SDM and goal-setting for malnutrition interventions.
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| 65. |
- Andersson, Anna Karin, et al.
(författare)
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Patterns of everyday functioning in preschool children born preterm and at term
- 2017
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Ingår i: Research in Developmental Disabilities. - : Elsevier BV. - 0891-4222 .- 1873-3379. ; 67, s. 82-93
-
Tidskriftsartikel (refereegranskat)abstract
- Background/Aim: Children born preterm are at risk of neonatal complications but the long-term consequences for everyday functioning is not well known. The study aimed to identify patterns of everyday functioning in preschool children born preterm and at term in relation to perinatal data, neonatal risk factors, behaviour, and socioeconomic status. Registry data and data from parent rated questionnaires were collected for 331 children.Method: A person-oriented approach with a cluster analysis was used.Results: A seven cluster solution explained 65.91% of the variance. Most children (n = 232) showed patterns of strong everyday functioning. A minority of the children (n = 99), showed diverse patterns of weak everyday functioning. Perinatal characteristics, neonatal risk factors and socio-economics did not predict cluster group membership. Children born preterm were represented in all clusters.Conclusion, implications: Most preschool children are perceived by their parents with strong everyday functioning despite being born preterm. However small groups of children are, for various reasons, perceived with weak functioning, but preterm birth is not the sole contributor to patterns of weak everyday functioning. More critical for all children's everyday functioning is probably the interaction between individual factors, behavioural factors and contextual factors. To gain a broader understanding of children's everyday functioning. Child Health Services need to systematically consider aspects of body function, activity and in addition participation and environmental aspects.
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| 66. |
- Andersson, Jonathan, et al.
(författare)
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MRI estimates of brown adipose tissue in children - Associations to adiposity, osteocalcin, and thigh muscle volume
- 2019
-
Ingår i: Magnetic Resonance Imaging. - : Elsevier BV. - 0730-725X .- 1873-5894. ; 58, s. 135-142
-
Tidskriftsartikel (refereegranskat)abstract
- Context Brown adipose tissue is of metabolic interest. The tissue is however poorly explored in children. Methods: Sixty-three 7-year old subjects from the Swedish birth-cohort Halland Health and Growth Study were recruited. Care was taken to include both normal weight and overweight children, but the subjects were otherwise healthy. Only children born full term were included. Water-fat separated whole-body MRI scans, anthropometric measurements, and measurements of fasting glucose and levels of energy homeostasis related hormones, including the insulin-sensitizer osteocalcin, were performed. The fat fraction (FF) and effective transverse relaxation time (T-2(star)) of suspected brown adipose tissue in the cervical-supraclavicular-axillary fat depot (sBAT) and the FFs of abdominal visceral (VAT) and subcutaneous adipose tissue (SAT) were measured. Volumes of sBAT, abdominal VAT and SAT, and thigh muscle volumes were measured. Results: The FF in the sBAT depot was lower than in VAT and SAT for all children. In linear correlations including sex and age as explanatory variables, sBAT FF correlated positively with all measures of adiposity (p < 0.01), except for VAT FF and weight, positively with sBAT T-2* (p = 0.036), and negatively with osteocalcin (p = 0.017). When adding measures of adiposity as explanatory variables, sBAT FF also correlated negatively with thigh muscle volume (p < 0.01). Conclusions: Whole-body water-fat MRI of children allows for measurements of sBAT. The FF of sBAT was lower than that of VAT and SAT, indicating presence of BAT. Future studies could confirm whether the observed correlations corresponds to a hormonally active BAT.
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| 67. |
- Andersson, Jonathan, et al.
(författare)
-
Water-fat separation incorporating spatial smoothing is robust to noise
- 2018
-
Ingår i: Magnetic Resonance Imaging. - : Elsevier BV. - 0730-725X .- 1873-5894. ; 50, s. 78-83
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To develop and evaluate a noise-robust method for reconstruction of water and fat images for spoiled gradient multi-echo sequences.METHODS: The proposed method performs water-fat separation by using a graph cut to minimize an energy function consisting of unary and binary terms. Spatial smoothing is incorporated to increase robustness to noise. The graph cut can fail to find a solution covering the entire image, in which case the relative weighting of the unary term is iteratively increased until a complete solution is found. The proposed method was compared to two previously published methods. Reconstructions were performed on 16 cases taken from the 2012 ISMRM water-fat reconstruction challenge dataset, for which reference reconstructions were provided. Robustness towards noise was evaluated by reconstructing images with different levels of noise added. The percentage of water-fat swaps were calculated to measure performance.RESULTS: At low noise levels the proposed method produced similar results to one of the previously published methods, while outperforming the other. The proposed method significantly outperformed both of the previously published methods at moderate and high noise levels.CONCLUSION: By incorporating spatial smoothing, an increased robustness towards noise is achieved when performing water-fat reconstruction of spoiled gradient multi-echo sequences.
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| 68. |
- Andrean, Stefio Y., 1991-, et al.
(författare)
-
Probing the CP nature of the top–Higgs Yukawa coupling in tt¯H??¯? and tH events with H→bb¯?→??¯ decays using the ATLAS detector at the LHC
- 2024
-
Ingår i: Physics Letters B. - : Elsevier B.V.. - 0370-2693 .- 1873-2445. ; 849
-
Tidskriftsartikel (refereegranskat)abstract
- The CP properties of the coupling between the Higgs boson and the top quark are investigated using 139 fb−1 of proton–proton collision data recorded by the ATLAS experiment at the LHC at a centre-of-mass energy of s√=13?=13 TeV. The CP structure of the top quark–Higgs boson Yukawa coupling is probed in events with a Higgs boson decaying into a pair of b-quarks and produced in association with either a pair of top quarks, tt¯H??¯?, or a single top quark, tH. Events containing one or two electrons or muons are used for the measurement. Multivariate techniques are used to select regions enriched in tt¯H??¯? and tH events, where dedicated CP-sensitive observables are exploited. In an extension of the Standard Model (SM) with a CP-odd admixture in the top–Higgs Yukawa coupling, the mixing angle between CP-even and CP-odd couplings is measured to be α=11∘+52∘−73∘?=11−73∘∘+52∘, compatible with the SM prediction corresponding to α=0?=0.
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| 69. |
- Arghand, Taha, et al.
(författare)
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An experimental investigation of the flow and comfort parameters for under-floor, confluent jets and mixing ventilation systems in an open-plan office
- 2015
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Ingår i: Building and Environment. - : Elsevier BV. - 0360-1323 .- 1873-684X. ; 92, s. 48-60
-
Tidskriftsartikel (refereegranskat)abstract
- There is a new trend to convert the workplaces from individual office rooms to open offices for motivating money saving and better communication. With such a shift the ability of existing ventilation systems in meeting the new requirements is a challenging question for researchers. The available options could have an impact on workers' health in terms of providing acceptable levels of thermalcomfort and indoor air quality. Thus, this experimental investigation focuses on the performances of three different air distribution systems in an open-plan office space. The investigated systems were: mixing ventilation with ceiling-mounted inlets, confluent jets ventilation and underfloor air distribution with straight and curved vanes. Although this represents a small part of our more extensiveexperimental investigation, the results show that all the purposed stratified ventilation systems (CJV and UFAD) were more or less behaving as mixing systems with some tendency for displacement effects. Nevertheless, it is known that the mixing systems have a stable flow pattern but has the disadvantage of mixing contaminated air with the fresh supplied air which may produce lower performance and in worst cases occupants' illness. For the open-plan office we studied here, it will be shown that the new systems are capable of performing better than the conventional mixing systems. As expected, the higher air exchange efficiency in combination with lower local mean age of air for corner-mounted CJV and floor-mounted UFAD grills systems indicates that these systems are suitable for open-plan offices and are to be favored over conventional mixing systems.
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| 70. |
- Arkblad, Eva L, et al.
(författare)
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Multiplex ligation-dependent probe amplification improves diagnostics in spinal muscular atrophy
- 2006
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Ingår i: Neuromuscular disorders : NMD. - : Elsevier BV. - 0960-8966 .- 1873-2364. ; 16:12, s. 830-8
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Tidskriftsartikel (refereegranskat)abstract
- Spinal muscular atrophy (SMA) is an autosomal recessive disease caused by decreased levels of survival motor neuron protein (SMN). In the majority of cases, this decrease is due to absence of the SMN1 gene. Multiplex ligation-dependent probe amplification (MLPA) is a modern quantitative molecular method. Applied in SMA cases, it improves diagnostics by simultaneously identifying the number of copies of several target sequences in the SMN1 gene and in nearby genes. Using MLPA in clinical diagnostics, we have identified a previously unreported, partial deletion of SMN1 (exons 1-6) in two apparently unrelated Swedish families. This mutation would not have been detected by conventional diagnostic methods. This paper illustrates the broad clinical and genetic spectrum of SMA and includes reports of MLPA results and clinical descriptions of a patient with homozygous absence of SMN1 and only one SMN2 (prenatal onset SMA type 1), an asymptomatic woman with five SMN2 (lacking SMN1) and representative patients with SMA types 1, 2 and 3.
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