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The procedure for the energy calibration of the high granularity electromagnetic calorimeter PHOS of the ALICE experiment is presented. The methods used to perform the relative gain calibration, to evaluate the geometrical alignment and the corresponding correction of the absolute energy scale, to obtain the nonlinearity correction coefficients and finally, to calculate the time-dependent calibration corrections, are discussed and illustrated by the PHOS performance in proton-proton (pp) collisions at s√=13 TeV. After applying all corrections, the achieved mass resolution of π0 and η mesons for pT>1.7 GeV/c is σπ0m=4.56±0.03 MeV/c2 and σηm=15.3±1.0 MeV/c2.
The procedure for the energy calibration of the high granularity electromagnetic calorimeter PHOS of the ALICE experiment is presented. The methods used to perform the relative gain calibration, to evaluate the geometrical alignment and the corresponding correction of the absolute energy scale, to obtain the nonlinearity correction coefficients and finally, to calculate the time-dependent calibration corrections, are discussed and illustrated by the PHOS performance in proton-proton (pp) collisions at s√ = 13 TeV. After applying all corrections, the achieved mass resolutions for π0 and η mesons for pT>1.7 GeV/c are σπ0m=4.56±0.03 MeV/c2 and σηm=15.3±1.0 MeV/c2, respectively.
Scattering studies with low-energy kaon-proton femtoscopy in proton-proton collisions at the LHC
(2020)
The study of the strength and behaviour of the antikaon-nucleon (K¯¯¯¯N) interaction constitutes one of the key focuses of the strangeness sector in low-energy Quantum Chromodynamics (QCD). In this letter a unique high-precision measurement of the strong interaction between kaons and protons, close and above the kinematic threshold, is presented. The femtoscopic measurements of the correlation function at low pair-frame relative momentum of (K+ p ⊕ K− p¯¯¯) and (K− p ⊕ K+ p¯¯¯) pairs measured in pp collisions at s√ = 5, 7 and 13 TeV are reported. A structure observed around a relative momentum of 58 MeV/c in the measured correlation function of (K− p ⊕ K+ p¯¯¯) with a significance of 4.4. σ constitutes the first experimental evidence for the opening of the (K¯¯¯¯0n⊕K0n¯¯¯) isospin breaking channel due to the mass difference between charged and neutral kaons. The measured correlation functions have been compared to Jülich and Kyoto models in addition to the Coulomb potential. The high-precision data at low relative momenta presented in this work prove femtoscopy to be a powerful complementary tool to scattering experiments and provide new constraints above the K¯¯¯¯N threshold for low-energy QCD chiral models.
Scattering studies with low-energy kaon-proton femtoscopy in
proton–proton collisions at the LHC
(2019)
The study of the strength and behaviour of the antikaon-nucleon (K¯¯¯¯N) interaction constitutes one of the key focuses of the strangeness sector in low-energy Quantum Chromodynamics (QCD). In this letter a unique high-precision measurement of the strong interaction between kaons and protons, close and above the kinematic threshold, is presented. The femtoscopic measurements of the correlation function at low pair-frame relative momentum of (K+ p ⊕ K− p¯¯¯) and (K− p ⊕ K+ p¯¯¯) pairs measured in pp collisions at s√ = 5, 7 and 13 TeV are reported. A structure observed around a relative momentum of 58 MeV/c in the measured correlation function of (K− p ⊕ K+ p¯¯¯) constitutes the first experimental evidence for the opening of the (K¯¯¯¯0n⊕K0n¯¯¯) isospin breaking channel due to the mass difference between charged and neutral kaons. The measured correlation functions have been compared to several models. The high-precision data at low relative momenta presented in this work prove femtoscopy to be a powerful complementary tool to scattering experiments and provide new constraints above the K¯¯¯¯N threshold for low-energy QCD chiral models.
Scattering studies with low-energy kaon-proton femtoscopy in proton–proton collisions at the LHC
(2020)
The study of the strength and behaviour of the antikaon-nucleon (K¯¯¯¯N) interaction constitutes one of the key focuses of the strangeness sector in low-energy Quantum Chromodynamics (QCD). In this letter a unique high-precision measurement of the strong interaction between kaons and protons, close and above the kinematic threshold, is presented. The femtoscopic measurements of the correlation function at low pair-frame relative momentum of (K+ p ⊕ K− p¯¯¯) and (K− p ⊕ K+ p¯¯¯) pairs measured in pp collisions at s√ = 5, 7 and 13 TeV are reported. A structure observed around a relative momentum of 58 MeV/c in the measured correlation function of (K− p ⊕ K+ p¯¯¯) with a significance of 4.4. σ constitutes the first experimental evidence for the opening of the (K¯¯¯¯0n⊕K0n¯¯¯) isospin breaking channel due to the mass difference between charged and neutral kaons. The measured correlation functions have been compared to Jülich and Kyoto models in addition to the Coulomb potential. The high-precision data at low relative momenta presented in this work prove femtoscopy to be a powerful complementary tool to scattering experiments and provide new constraints above the K¯¯¯¯N threshold for low-energy QCD chiral models.
The procedure for the energy calibration of the high granularity electromagnetic calorimeter PHOS of the ALICE experiment is presented. The methods used to perform the relative gain calibration, to evaluate the geometrical alignment and the corresponding correction of the absolute energy scale, to obtain the nonlinearity correction coefficients and finally, to calculate the time-dependent calibration corrections, are discussed and illustrated by the PHOS performance in proton-proton (pp) collisions at √s=13 TeV. After applying all corrections, the achieved mass resolutions for π0 and η mesons for pT > 1.7 GeV/c are σmπ0 = 4.56 ± 0.03 MeV/c2 and σmη = 15.3 ± 1.0 MeV/c2, respectively.
The ALICE Collaboration reports a differential measurement of inclusive jet suppression using pp and Pb−Pb collision data at a center-of-mass energy per nucleon-nucleon collision sNN−−−√=5.02 TeV. Charged-particle jets are reconstructed using the anti-kT algorithm with resolution parameters R= 0.2, 0.3, 0.4, 0.5, and 0.6 in pp collisions and R= 0.2, 0.4, 0.6 in central (0−10%), semi-central (30−50%), and peripheral (60−80%) Pb−Pb collisions. A novel approach based on machine learning is employed to mitigate the influence of jet background. This enables measurements of inclusive jet suppression in new regions of phase space, including down to the lowest jet pT≥40 GeV/c at R=0.6 in central Pb−Pb collisions. This is an important step for discriminating different models of jet quenching in the quark-gluon plasma. The transverse momentum spectra, nuclear modification factors, derived cross section, and nuclear modification factor ratios for different jet resolution parameters of charged-particle jets are presented and compared to model predictions. A mild dependence of the nuclear modification factor ratios on collision centrality and resolution parameter is observed. The results are compared to a variety of jet-quenching models with varying levels of agreement.
The spread of the COVID-19 virus was met by a strict lockdown in many countries around the world, with the closure of all physical activity (PA) facilities and limitations on moving around freely. The aim of the present online survey was to assess the effect of lockdown on physical activity in Italy. Physical activity was assessed using the European Health Interview Survey questionnaire. A total of 1500 datasets were analyzed. Differences between conditions were tested with a chi2-based (χ2) test for categorical variables, and with the Student’s t-test for paired data. A fixed effects binary logistic regression analysis was conducted to identify relevant predictor variables to explain the compliance with World Health Organisation (WHO) recommendations. We found a substantial decline in all physical activity measures. Mean differences in walking and cycling metabolic equivalent of task minutes per week (METmin/week), respectively, were 344.4 (95% confidence interval (95% CI): 306.6–382.2; p < 0.001) and 148.5 (95% CI: 123.6–173.5; p < 0.001). Time spent in leisure time decreased from 160.8 to 112.6 min/week (mean difference 48.2; 95% CI: 40.4–56.0; p < 0.001). Compliance with WHO recommendations decreased from 34.9% to 24.6% (chi2 (1, 3000) = 38.306, p < 0.001, V = 0.11). Logistic regression showed a reduced chance (OR 0.640, 95% CI: 0.484–0.845; p = 0.001) to comply with WHO PA recommendations under lockdown conditions. Measures to promote physical activity should be intensified to limit detrimental health effects.
Germany experienced a 6-month second lockdown (November 2020–April 2021) during the COVID-19 pandemic, which included the closure of all physical activity (PA) facilities. The use of online exercise classes (OECs) was promoted by public health and exercise organizations. Using the present cross-sectional online survey, we assess the use of and opinion towards OECs in Germany during the second lockdown. We used contingency tables and the Chi2 test to calculate the frequency of awareness and use of OECs according to PA status, well-being and demographic data, and conducted a binary logistic regression with OEC awareness or use and dichotomized independent predictors. The associations between opinion and activity status, frequency of use, educational attainment, age and body mass index were calculated using Spearman correlations. A total of 993 datasets were analyzed in detail. Of the 785 (79.1%) participants reporting awareness of OECs, 536 tried them, and 262, 188 and 85 used them <1 per week, 1–2 per week and ≥3 per week, respectively. The users were typically active, female participants with poorer mental well-being. The opinions towards OECs varied according to participant characteristics, such as activity status, BMI and age. Overall, regular OEC use was quite limited, and, as such, cannot replace in-person exercise opportunities. Keeping physical activity facilities open and safe must be prioritized in the ongoing pandemic.
Physical activity and well-being during the second COVID19-related lockdown in Germany in 2021
(2021)
In the second wave of the COVID-19 pandemic in Germany, lockdown measures were reinstalled and were in place between November 2020 and April 2021, including the closure of physical activity facilities. The aim of the current online survey was to assess the lockdown effects on physical activity and well-being in the general population. Pre-lockdown vs. lockdown differences were tested with the Χ2 test and the Student’s t-test for paired data. Predictor variables to explain compliance with physical activity recommendations were identified using a fixed-effects binary logistic regression analysis. Data of 993 respondents were analyzed. Transport-related and leisure-time physical activity decreased (p < 0.001, d = 0.25, and p < 0.001, d = 0.33, respectively). Compliance with physical activity recommendations decreased from 42.2% to 29.4% (chi2 (1, 1986) = 35.335, p < 0.001, V = 0.13). Well-being decreased significantly (t (990) = 23.405, p < 0.001) by 16.3 points (d = 0.74). Physical activity and well-being declined in German adults during the second COVID-19-related lockdown. Physical activity should be promoted also in light of the emerging evidence on its protective effects against COVID-19.
Environmental change impacts on the C- and N-cycle of European forests: a model comparison study
(2013)
Forests are important components of the greenhouse gas balance of Europe. There is considerable uncertainty about how predicted changes to climate and nitrogen deposition will perturb the carbon and nitrogen cycles of European forests and thereby alter forest growth, carbon sequestration and N2O emission. The present study aimed to quantify the carbon and nitrogen balance, including the exchange of greenhouse gases, of European forests over the period 2010–2030, with a particular emphasis on the spatial variability of change. The analysis was carried out for two tree species: European beech and Scots pine. For this purpose, four different dynamic models were used: BASFOR, DailyDayCent, INTEGRATOR and Landscape-DNDC. These models span a range from semi-empirical to complex mechanistic. Comparison of these models allowed assessment of the extent to which model predictions depended on differences in model inputs and structure. We found a European average carbon sink of 0.160 ± 0.020 kgC m−2 yr−1 (pine) and 0.138 ± 0.062 kgC m−2 yr−1 (beech) and N2O source of 0.285 ± 0.125 kgN ha−1 yr−1 (pine) and 0.575 ± 0.105 kgN ha−1 yr−1 (beech). The European average greenhouse gas potential of the carbon sink was 18 (pine) and 8 (beech) times that of the N2O source. Carbon sequestration was larger in the trees than in the soil. Carbon sequestration and forest growth were largest in central Europe and lowest in northern Sweden and Finland, N. Poland and S. Spain. No single driver was found to dominate change across Europe. Forests were found to be most sensitive to change in environmental drivers where the drivers were limiting growth, where changes were particularly large or where changes acted in concert. The models disagreed as to which environmental changes were most significant for the geographical variation in forest growth and as to which tree species showed the largest rate of carbon sequestration. Pine and beech forests were found to have differing sensitivities to environmental change, in particular the response to changes in nitrogen and precipitation, with beech forest more vulnerable to drought. There was considerable uncertainty about the geographical location of N2O emissions. Two of the models BASFOR and LandscapeDNDC had largest emissions in central Europe where nitrogen deposition and soil nitrogen were largest, whereas the two other models identified different regions with large N2O emission. N2O emissions were found to be larger from beech than pine forests and were found to be particularly sensitive to forest growth.
Forests are important components of the greenhouse gas balance of Europe. There is considerable uncertainty about how predicted changes to climate and nitrogen deposition will perturb the carbon and nitrogen cycles of European forests and thereby alter forest growth, carbon sequestration and N2O emission. The present study aimed to quantify the carbon and nitrogen balance, including the exchange of greenhouse gases, of European forests over the period 2010–2030, with a particular emphasis on the spatial variability of change. The analysis was carried out for two tree species: European beech and Scots pine. For this purpose, four different dynamic models were used: BASFOR, DailyDayCent, INTEGRATOR and Landscape-DNDC. These models span a range from semi-empirical to complex mechanistic. Comparison of these models allowed assessment of the extent to which model predictions depended on differences in model inputs and structure. We found a European average carbon sink of 0.160 ± 0.020 kgC m−2 yr−1 (pine) and 0.138 ± 0.062 kgC m−2 yr−1 (beech) and N2O source of 0.285 ± 0.125 kgN ha−1 yr−1 (pine) and 0.575 ± 0.105 kgN ha−1 yr−1 (beech). The European average greenhouse gas potential of the carbon source was 18 (pine) and 8 (beech) times that of the N2O source. Carbon sequestration was larger in the trees than in the soil. Carbon sequestration and forest growth were largest in central Europe and lowest in northern Sweden and Finland, N. Poland and S. Spain. No single driver was found to dominate change across Europe. Forests were found to be most sensitive to change in environmental drivers where the drivers were limiting growth, where changes were particularly large or where changes acted in concert. The models disagreed as to which environmental changes were most significant for the geographical variation in forest growth and as to which tree species showed the largest rate of carbon sequestration. Pine and beech forests were found to have differing sensitivities to environmental change, in particular the response to changes in nitrogen and precipitation, with beech forest more vulnerable to drought. There was considerable uncertainty about the geographical location of N2O emissions. Two of the models BASFOR and LandscapeDNDC had largest emissions in central Europe where nitrogen deposition and soil nitrogen were largest whereas the two other models identified different regions with large N2O emission. N2O emissions were found to be larger from beech than pine forests and were found to be particularly sensitive to forest growth.
Wenn eine historische Epoche mit dem Prädikat "mobil" ausgezeichnet werden kann, dann doch wohl die unsrige. Mit diesem weitverbreiteten Irrtum macht der Mediävist Schluss: In der Auseinandersetzung mit dem Mittelalter können wir selbst überprüfen, ob unsere Vorstellungen von der Mobilität in Vergangenheit und Gegenwart noch haltbar sind.
Repeated Quaternary glaciations have significantly shaped the present distribution and diversity of several European species in aquatic and terrestrial habitats. To study the phylogeography of freshwater invertebrates, patterns of intraspecific variation have been examined primarily using mitochondrial DNA markers that may yield results unrepresentative of the true species history. Here, population genetic parameters were inferred for a montane aquatic caddisfly, T hremma gallicum , by sequencing a 658‐bp fragment of the mitochondrial CO 1 gene, and 12,514 nuclear RAD loci. T . gallicum has a highly disjunct distribution in southern and central Europe, with known populations in the Cantabrian Mountains, Pyrenees, Massif Central, and Black Forest. Both datasets represented rangewide sampling of T. gallicum . For the CO 1 dataset, this included 352 specimens from 26 populations, and for the RAD dataset, 17 specimens from eight populations. We tested 20 competing phylogeographic scenarios using approximate Bayesian computation (ABC ) and estimated genetic diversity patterns. Support for phylogeographic scenarios and diversity estimates differed between datasets with the RAD data favouring a southern origin of extant populations and indicating the Cantabrian Mountains and Massif Central populations to represent highly diverse populations as compared with the Pyrenees and Black Forest populations. The CO 1 data supported a vicariance scenario (north–south) and yielded inconsistent diversity estimates. Permutation tests suggest that a few hundred polymorphic RAD SNP s are necessary for reliable parameter estimates. Our results highlight the potential of RAD and ABC‐based hypothesis testing to complement phylogeographic studies on non‐model species.
For the environs of the Late Bronze Age fortification enclosure Iarcuri the hydro-morphological relief characteristics are combined with archaeological evidences. Target of the study is to evaluate the impact of settlement activities in the surroundings of Iarcuri on the development of the channel network. Data analysis is based on topographic map-derived and high resolution DEMs provided by LiDAR scanning; derivatives of the DEMs are used to characterize the different sub-catchments that show varying influences by the fortification ramparts. The tributaries reaching the receiving stream close to the central settlement area source close to the gates in the ramparts in the Late Bronze Age built-up areas. Additionally, also the geometry of these tributaries differs from that of other tributaries. The distinct character of the channel network with repeatedly occurring rectangular bends indicates the capture of channels, which developed as gullies along paths by retrogressive erosion.
In many markets, design is one of the key factors in determining a product’s success. The present research offers insights into the role of design for the success of cars, and offers procedures to measure the quality of the designs objectively. The authors show that visual design plays a major role in a product’s success in the automobile market. In the study, two visual design aspects were already sufficient to significantly improve traditional sales forecasting models for cars. Visual prototypicality and visual complexity both had a positive impact on sales, and designs that were perceived as both prototypical and complex were the ones that displayed the best results. Most design evaluation used to be based on subjective measures, but the researcher applied a new, objective procedure to measure prototypicality and complexity. While the latter was detected by the disk space needed by the compressed image file, the new approach for measuring prototypicality was even more sophisticated. It relied on the technique of image morphing. Morphing is a technique that allows the construction of a visual synthesis – or average picture – from a number of individual pictures. Once a car morph is developed, one can determine the visual similarity of different car models to the morph in order to obtain its prototypicality. In principle, this procedure can be automated completely, and including a large number of versions is possible. These measures therefore seem suitable for supporting design decision processes in practice.
The success stories of design-oriented companies like Apple, Audi or Nike have put design on the agenda in many marketing departments. Consumers cannot elude the effect of aesthetics and therefore design is a major factor for business success. Typically consumers choose the product with the best design, all other aspects being equal. Only when the interplay of product characteristics, brand and design is carefully coordinated can successful products be created. This requires an integrated approach to design, one which is applied right at the beginning of the value chain. Product development, marketing and design need to work in close cooperation, communicate well and frequently, and collect feedback from the market. Superior aesthetics are always important but should be a top priority in cases where efficiency-oriented Asian competitors are able to offer functionally similar products at much lower prices.
Although existing research has established that aesthetic pleasure and aesthetic interest are two distinct positive aesthetic responses, empirical research on aesthetic preferences usually considers only aesthetic liking to capture participants’ aesthetic response. This causes some fundamental contradictions in the literature; some studies find a positive relationship between easy-to-process stimulus characteristics and aesthetic liking, while others suggest a negative relationship. The present research addresses these empirical contradictions by investigating the dual character of aesthetic liking as manifested in both the pleasure and interest components. Based on the Pleasure-Interest Model of Aesthetic Liking (PIA Model; Graf and Landwehr, 2015), two studies investigated the formation of pleasure and interest and their relationship with aesthetic liking responses. Using abstract art as the stimuli, Study 1 employed a 3 (stimulus fluency: low, medium, high) × 2 (processing style: automatic, controlled) × 2 (aesthetic response: pleasure, interest) experimental design to examine the processing dynamics responsible for experiencing aesthetic pleasure versus aesthetic interest. We find that the effect of stimulus fluency on pleasure is mediated by a gut-level fluency experience. Stimulus fluency and interest, by contrast, are related through a process of disfluency reduction, such that disfluent stimuli that grow more fluent due to processing efforts become interesting. The second study employed product designs (bikes, chairs, and lamps) as stimuli and a 2 (fluency: low, high) × 2 (processing style: automatic, controlled) × 3 (product type: bike, chair, lamp) experimental design to examine pleasure and interest as mediators of the relationship between stimulus fluency and design attractiveness. With respect to lamps and chairs, the results suggest that the effect of stimulus fluency on attractiveness is fully mediated by aesthetic pleasure, especially in the automatic processing style. Conversely, disfluent product designs can enhance design attractiveness judgments due to interest when a controlled processing style is adopted.
Hintergrund: Der eigene Körper ist das zentrale Arbeitsinstrument eines*einer Tanzpädagog*in (TP) innerhalb der Bewegungsvermittlung. Bisher fehlen Erkenntnisse über die subjektive Wahrnehmung der eigenen berufsassoziierten Gesundheit und Zufriedenheit sowie die Identifizierung gesundheitsbelastender Berufsmerkmale.
Methodik: Im Rahmen einer fragebogenbasierten Querschnittserhebung wurde eine Kohorte von TP in Deutschland zur eigenen Gesundheit und generellen Berufszufriedenheit und belastenden Aspekten im Zusammenhang mit ihrer Berufsausübung untersucht. Zusätzlich wurden allgemeine anthropometrische und soziodemographische Merkmale erfasst. Neben der Betrachtung der Gesamtkohorte wurde auf geschlechtsspezifische Unterschiede getestet. In die statistische Analyse wurden n = 232 TP (m: 51/w: 181) im Alter von 43,1 ± 11,0 Jahren eingeschlossen.
Ergebnisse: Der allgemeine Gesundheitszustand wurde von 85,3 % der Befragten mit „befriedigend“ (26,1 %) bis „sehr gut“ (14,7 %) beurteilt. 59,2 % der Tanzpädagog*innen schätzten ihre Gesundheit „gut“ (35,3 %) bis „sehr gut“ ein. Es herrschte eine hohe Zufriedenheit mit der eigenen Berufsausübung für 80 % der Teilnehmenden. Die TP fühlten sich überwiegend in der Lage (trifft „voll & ganz“ bzw. „eher zu“), mit den physischen (75,7 %) und psychischen Berufsanforderungen (70,3 %) umzugehen. Als belastende Berufsmerkmale in der Eigenwahrnehmung können neben Zukunftsängsten (51,5 %) vor allem arbeitsorganisatorische (fehlende Zeit für Familie und Freunde bei 28,4 %) und ökonomische Aspekte (Einkommensunsicherheit bei 61,0 % und fehlende Altersabsicherung bei 65,7 %) herausgestellt werden.
Diskussion: Die Berufsausübung als TP geht mit einer hohen generellen Zufriedenheit und einem positiven Empfinden des eigenen Gesundheitszustandes einher. Eine Bestätigung dieser positiven Ergebnisse durch Verletzungs- und Erkrankungsstatistiken steht noch aus. Darüber hinaus wäre eine Verbesserung arbeitsorganisatorischer und ökonomischer Aspekte wünschenswert.