bluuebunny/crossref_metadata_2025_split huggingface dataset:
The pneumatic wheel model with plastic elements and force loss
Authors: Miroslaw Tomasz 
Published: January 2021

AbstractWheel construction and adhesion to the road decide on transport economy and safety. People are still developing wheel rims and tries to increase vehicle stability, reduce energy consumption and noise emissions. For many years designers have developed many models to describe the tire‐road phenomena. The models are created in a couple of ways, some tried to find the mathematical equation which follows the experiment resets, others tried to explain the phenomena itself. Some examples are presented in this paper. The brush Pacejca and LuGre models were developed to a new model to explain the process of vehicle force generation with longitudinal and lateral slips. When the wheel is propelled or braked, the force is transferred between rim and tire to the road by elastic blocks. Because of that, the difference of speed between the external part of the tire and the rim appears what results in tire longitudinal and lateral deformations. Based on Columbus friction model with Stribeck effect the model of force flow with tire deformation was presented for three models of friction. The two directional (lateral and longitudinal) slip and energy loses were worked out. The concept of the force flow model for dynamic processes modeling is presented. It refers to the force carried by the rotating part of the tire which loses the contact with a road. The friction force decreases and wheel has to accelerate until the new deformation compensates the “lost force.” Some examples of simulation results based on presented methods are shown and they seem to be consistent with other results from other accepted models.
Climate Change Adaptation in Southern Africa: Universalistic Science or Indigenous Knowledge or Hybrid
Authors: Mutambisi Tafadzwa , Chanza Nelson , Matamanda Abraham R. , Ncube Roseline , Chirisa Innocent 
Published: January 2021

AbstractThe aims of this chapter are to seek answer, through a document review, case studies, and thematic content analysis, to which direction Southern Africa should take in the face of climate change and to suggest a framework for adaptations by communities experiencing climatic events. Acknowledging that the fundamental set of ideas provided by indigenous knowledge (IK) works best at a small scale, the chapter argues for the need to seriously value IK-based response practices in the knowledge hybridization agenda. The worsening vulnerability potentiated by the increasing magnitude and severity of climate change impacts is a reminder that local-based indigenous response practices in Africa need to be complemented. Adaptation to climate change calls for real and surreal measures all being applied in combination. Across Africa, these measures have, at times, included the preservation of forest resources which increased carbon sinking and enhanced community resilience against climate change. Universalistic and orthodox sciences have punctuated and amplified these efforts by speaking of such initiatives as mitigation and adaptation through programs, e.g., Reducing Emissions from Deforestation and Forest Degradation (REDD+) and ecosystem-based adaptation (EbA). The merits of the two approaches have resulted in increasing call among scholars for the merging of these programs with IK. However, it remains to be fully understood how such a hybrid approach could be operationalized without treating the latter as an inferior element in climate science discourses.
Effective actions for dual massive (super) p-forms
Authors: Kuzenko Sergei M. , Turner Kai 
Published: January 2021

Abstract
In d dimensions, the model for a massless p-form in curved space is known to be a reducible gauge theory for p > 1, and therefore its covariant quantisation cannot be carried out using the standard Faddeev-Popov scheme. However, adding a mass term and also introducing a Stueckelberg reformulation of the resulting p-form model, one ends up with an irreducible gauge theory which can be quantised à la Faddeev and Popov. We derive a compact expression for the massive p-form effective action, $$ {\Gamma}_p^{(m)} $$

Γ
p

m

, in terms of the functional determinants of Hodge-de Rham operators. We then show that the effective actions $$ {\Gamma}_p^{(m)} $$

Γ
p

m

and $$ {\Gamma}_{d-p-1}^{(m)} $$

Γ

d
−
p
−
1

m

differ by a topological invariant. This is a generalisation of the known result in the massless case that the effective actions Γp and Γd−p−2 coincide modulo a topological term. Finally, our analysis is extended to the case of massive super p-forms coupled to background $$ \mathcal{N} $$
N
= 1 supergravity in four dimensions. Specifically, we study the quantum dynamics of the following massive super p-forms: (i) vector multiplet; (ii) tensor multiplet; and (iii) three-form multiplet. It is demonstrated that the effective actions of the massive vector and tensor multiplets coincide. The effective action of the massive three-form is shown to be a sum of those corresponding to two massive scalar multiplets, modulo a topological term.
Mimetic gravity in (2 + 1)-dimensions
Authors: Sheykhi Ahmad 
Published: January 2021

Abstract
One of the most important achievements in general relativity has been discovery of the (2 + 1)-dimensional black hole solutions of Einstein gravity in anti-de Sitter (AdS) spacetime [7]. In this paper, we construct, for the first time, the (2 + 1)-dimensional solutions of mimetic theory of gravity. These solutions may provide a powerful background to investigate the physical properties of mimetic gravity and examine its viability in lower spacetime dimensions. In particular, some physical properties of stationary black hole solutions of this theory in the presence of charge or angular momentum are investigated.
More on $$ \mathcal{N} $$ =2 S-folds
Authors: Giacomelli Simone , Martone Mario , Tachikawa Yuji , Zafrir Gabi 
Published: January 2021

Abstract
We carry out a systematic study of 4d $$ \mathcal{N} $$
N
= 2 preserving S-folds of F-theory 7-branes and the worldvolume theories on D3-branes probing them. They consist of two infinite series of theories, which we denote following [1, 2] by $$ {\mathcal{S}}_{G,\mathrm{\ell}}^{(r)} $$

S

G
,
ℓ

r

for ℓ = 2, 3, 4 and $$ {\mathcal{T}}_{G,\mathrm{\ell}}^{(r)} $$

T

G
,
ℓ

r

for ℓ = 2, 3, 4, 5, 6. Their distinction lies in the discrete torsion carried by the S-fold and in the difference in the asymptotic holonomy of the gauge bundle on the 7-brane. We study various properties of these theories, using diverse field theoretical and string theoretical methods.
Operational experience of the Dutch helicopter emergency medical services (HEMS) during the initial phase of the COVID-19 pandemic: jeopardy on the prehospital care system?
Authors: Rikken Quinten G. H. , Mikdad Sarah , Mota Mathijs T. Carvalho , De Leeuw Marcel A. , Schober Patrick , Schwarte Lothar A. , Giannakopoulos Georgios F. 
Published: January 2021

Abstract
Purpose
The SARS-CoV-2 virus has disrupted global and local medical supply chains. To combat the spread of the virus and prevent an uncontrolled outbreak with limited resources, national lockdown protocols have taken effect in the Netherlands since March 13th, 2020. The aim of this study was to describe the incidence, type and characteristics of HEMS and HEMS-ambulance ‘Lifeliner 1’ dispatches during the initial phase of the COVID-19 pandemic compared to the same period one year prior.

Methods
A retrospective review of all HEMS and HEMS-ambulance ‘Lifeliner 1’ dispatches was performed from the start of Dutch nationwide lockdown orders from March 13th until May 13th, 2020 and the corresponding period one year prior. Dispatch-, operational-, patient-, injury-, and on-site treatment characteristics were extracted for analysis. In addition, the rate of COVID-19 positively tested HEMS personnel and the time physicians were unable to take call was described.

Results
During the initial phase of the COVID-19 pandemic, the HEMS and HEMS-ambulance was requested in 528 cases. One year prior, a total of 620 requests were received. The HEMS (helicopter and ambulance) was cancelled after deployment in 56.4% of the COVID-19 cohort and 50.7% of the historical cohort (P = 0.05). Incident location type did not differ between the two cohorts, specifically, there was no significant difference in the number of injuries that occurred at home in pandemic versus non-pandemic circumstances. Besides a decrease in the number of falls, the distribution of mechanisms of injury remained similar during the COVID-19 study period. There was no difference in self-inflicted injuries observed. Prehospital interventions remained similar during the COVID-19 pandemic compared to one year prior. Specifically, prehospital intubation did not differ between the two cohorts. The rate of COVID-19 positively tested HEMS personnel was 23.1%. Physicians who tested positive were unable to take call for a mean of 25 days (range 8–53).

Conclusion
A decrease in the number of deployments and increase in the number of cancelled missions was observed during the COVID-19 study period. No major differences in operational- and injury characteristics were found for HEMS and HEMS-ambulance dispatches between the initial phase of the COVID-19 pandemic in the Netherlands and the same period one year prior. These findings highlight the importance of continued operability of the HEMS, even during pandemic circumstances.

Level of evidence
III, retrospective comparative study.
Does moderate weight loss affect subjective health perception in obese individuals? Evidence from field experimental data
Authors: Hafner Lucas , Tauchmann Harald , Wübker Ansgar 
Published: January 2021

AbstractThis paper analyzes whether moderate weight reduction improves subjective health perception in obese individuals. Besides simple regression models, in a simultaneous equation framework we use randomized monetary weight loss incentives as instrument for weight change, to address possible endogeneity bias. In contrast to related earlier work that also employed instrumental variables estimation, identification does not rely on long-term, between-individuals weight variation, but on short-term, within-individual weight variation. Yet, our result does not suggest that the simple regressions suffer from much endogeneity bias, since instrumental variables estimation yields similar—though far noisily estimated and statistically insignificant—estimates. In qualitative terms, our results do not contradict previous findings pointing to weight loss in obese individuals resulting in improved subjective health. Our results suggest that a reduction of body weight by one BMI unit is associated with an increase in the probability of reporting self-rated health to be ‘satisfactory’ or better by 3 to 4 percentage points. This finding may encourage obese individuals in their weight loss attempts, since they are likely to be immediately rewarded for their efforts by subjective health improvements.
Tomography bounds for the Fourier extension operator and applications
Authors: Bennett Jonathan , Nakamura Shohei 
Published: January 2021

AbstractWe explore the extent to which the Fourier transform of an$$L^p$$Lpdensity supported on the sphere in$$\mathbb {R}^n$$Rncan have large mass on affine subspaces, placing particular emphasis on lines and hyperplanes. This involves establishing bounds on quantities of the form$$X(|\widehat{gd\sigma }|^2)$$X(|gdσ^|2)and$$\mathcal {R}(|\widehat{gd\sigma }|^2)$$R(|gdσ^|2), whereXand$$\mathcal {R}$$Rdenote the X-ray and Radon transforms respectively; here$$d\sigma $$dσdenotes Lebesgue measure on the unit sphere$$\mathbb {S}^{n-1}$$Sn-1, and$$g\in L^p(\mathbb {S}^{n-1})$$g∈Lp(Sn-1). We also identify some conjectural bounds of this type that sit between the classical Fourier restriction and Kakeya conjectures. Finally we provide some applications of such tomography bounds to the theory of weighted norm inequalities for$$\widehat{gd\sigma }$$gdσ^, establishing some natural variants of conjectures of Stein and Mizohata–Takeuchi from the 1970s. Our approach, which has its origins in work of Planchon and Vega, exploits cancellation via Plancherel’s theorem on affine subspaces, avoiding the conventional use of wave-packet and stationary-phase methods.
Spatial Variability of Microbial Communities and Salt Distributions Across a Latitudinal Aridity Gradient in the Atacama Desert
Authors: Shen Jianxun , Wyness Adam J. , Claire Mark W. , Zerkle Aubrey L. 
Published: January 2021

AbstractOver the past 150 million years, the Chilean Atacama Desert has been transformed into one of the most inhospitable landscapes by geophysical changes, which makes it an ideal Mars analog that has been explored for decades. However, a heavy rainfall that occurred in the Atacama in 2017 provides a unique opportunity to study the response of resident extremophiles to rapid environmental change associated with excessive water and salt shock. Here we combine mineral/salt composition measurements, amendment cell culture experiments, and next-generation sequencing analyses to study the variations in salts and microbial communities along a latitudinal aridity gradient of the Atacama Desert. In addition, we examine the reshuffling of Atacama microbiomes after the rainfall event. Analysis of microbial community composition revealed that soils within the southern arid desert were consistently dominated by Actinobacteria, Chloroflexi, Proteobacteria, Firmicutes, Bacteroidetes, Gemmatimonadetes, Planctomycetes, and Acidobacteria, and Verrucomicrobia. Intriguingly, the hyperarid microbial consortia exhibited a similar pattern to the more southern desert. Salts at the shallow subsurface were dissolved and leached down to a deeper layer, challenging indigenous microorganisms with the increasing osmotic stress. Microbial viability was found to change with aridity and rainfall events. This study sheds light on the structure of xerotolerant, halotolerant, and radioresistant microbiomes from the hyperarid northern desert to the less arid southern transition region, as well as their response to changes in water availability.
Climbing up the ladder: male reproductive behaviour changes with age in a long-lived fish
Authors: Šmejkal Marek , Bartoň Daniel , Brabec Marek , Sajdlová Zuzana , Souza Allan T. , Moraes Karlos R. , Soukalová Kateřina , Blabolil Petr , Vejřík Lukáš , Kubečka Jan 
Published: January 2021

Abstract
High reproductive performance is the key attribute of male fitness, especially due to the high reproductive skew among the males of most animal species. Males of long-lived iteroparous species have opportunities to improve upon their previous reproductive attempts with increasing age. We collected individual-specific reproductive behaviour and age data on a cyprinid fish, the asp (Leuciscus aspius), from 2015 to 2019. We tested whether males changed their performance over time using a unique dataset where individual performance was recorded yearly with passive telemetry. Individual fish behaviour was tracked from one to five reproductive seasons at least a year after the tagging. Fish were scored by measures of quality (first arrival time, number of visits and time spent in the reproductive grounds, and encountered proportion of males to all adult fish). In general, fish improved in the first three metrics with age, suggesting a shift towards behaviours likely to enhance reproductive success as individuals aged. A larger size at tagging was predictive of earlier fish arrival on the spawning ground in subsequent years. Our study therefore demonstrates the importance of age as a factor when considering the potential reproductive success of long-lived fish species.

Significance statement
High reproductive performance is the key attribute of male fitness. Males of long-lived species reproducing multiple times in their life have opportunities to improve upon their previous reproductive performance with increasing age. In this 5-year study, we tracked a large cyprinid fish with telemetry systems during their reproduction. We investigated the age-related behavioural changes in males and demonstrated the improvement of male reproductive timing and length of stay with potential repercussions for male’s reproductive output. We emphasize the importance of old and experienced individuals among the fish population, which are often targeted and selectively removed from the human-managed waters.
Associations of observer’s gender, Body Mass Index and internalization of societal beauty ideals to visual body processing
Authors: Cazzato Valentina , Walters Elizabeth R. , Urgesi Cosimo 
Published: January 2021

AbstractWe examined whether visual processing mechanisms of the body of conspecifics are different in women and men and whether these rely on westernised socio-cultural ideals and body image concerns. Twenty-four women and 24 men performed a visual discrimination task of upright or inverted images of female or male bodies and faces (Experiment 1) and objects (Experiment 2). In Experiment 1, both groups of women and men showed comparable abilities in the discrimination of upright and inverted bodies and faces. However, the gender of the human stimuli yielded different effects on participants’ performance, so that female faces, and male bodies appeared to be processed less configurally than female bodies and male faces, respectively. Interestingly, the reduction of configural processing for male bodies was significantly predicted by participants’ Body Mass Index (BMI) and their level of internalization of muscularity. Our findings suggest that configural visual processing of bodies and faces in women and men may be linked to a selective attention to detail needed for discriminating salient physical (perhaps sexual) cues of conspecifics. Importantly, BMI and muscularity internalization of beauty ideals may also play a crucial role in this mechanism.
Lernen und üben wir das Richtige?
Authors: Drews Patrick , Berger Maximilian , Sautter Johannes , Rohde Annika 
Published: January 2021

ZusammenfassungDer Massenanfall von Verletzten (MANV) ist eine Ausnahmesituation für Rettungsdienst und andere Einsatzkräfte. Trotz niedriger Inzidenz müssen sich die Einsatzkräfte sowohl auf ärztlicher als auch auf nichtärztlicher Seite auf diesen Einsatzfall vorbereiten. In der vorliegenden Pilotstudie wurden anhand einer Fehlermöglichkeits- und -einflussanalyse (FMEA) die kritischen Einsatzfaktoren im MANV ermittelt und mit den Ausbildungscurricula verglichen. Die herangezogenen Curricula waren Notfallsanitäter:in, organisatorische:r Leiter:in, Konzept zur katastrophenmedizinischen Ausbildung im studentischen Unterricht an deutschen Hochschulen, Nationaler Kompetenz-basierter Lernzielkatalog Medizin (NKLM), Zusatz-Weiterbildung Notfallmedizin und Fortbildung zum:zur leitenden Notarzt:ärztin. Die Ergebnisse lassen vermuten, dass in der praktischen Ausbildung der MANV eine eher untergeordnete Rolle spielt. Weitere empirische Untersuchungen sind aus Sicht der Autoren notwendig.
Factors related to the change in Swiss inpatient costs by disease: a 6-factor decomposition
Authors: Stucki Michael 
Published: January 2021

AbstractThere is currently little systematic knowledge about the contribution of different factors to the increase in health care spending in high-income countries such as Switzerland. The aim of this paper is to decompose inpatient care costs in the Swiss canton of Zurich by 100 diseases and 42 age/sex groups and to assess the contribution of six factors to the change in aggregate costs between 2013 and 2017. These six factors are population size, age and sex structure, inpatient treated prevalence, utilization in terms of stays per patient, length of stay per case, and costs per treatment day. Using detailed inpatient cost data at the case level, we find that the most important contributor to the change in disease-specific costs was a rise in costs per treatment day. For most conditions, this effect was partly offset by a reduction in the average length of stay. Changes in population size accounted for one third of the total increase, but population structure had only a small positive association with costs. The most expensive cases accounted for the largest part of the increase in costs, but the magnitude of this effect differed across diseases. A better understanding of the factors related to cost changes at the disease level over time is essential for the design of targeted health policies aiming at an affordable health care system.
Spatiotemporal seismic excitation of bridges with an anti-symmetrical first mode
Authors: Meibodi A. A. , Alexander N. A. 
Published: January 2021

AbstractThis study uses a generalized and parametrized reduced-order model in the frequency-domain to evaluate the effects of asynchronous excitation on the lateral response of bridge structures. Bridge geometry parametric regions, corresponding conceptually to valley profile shapes, are explored. Both modal and bounding analyses, that are dependent on bridge geometry alone, are employed to highlight regions where the first mode is anti-symmetrical and the likely error between identical support excitation (ISE) and multi-support excitation (MSE) analyses is large. Numerical time history analyses, using a heuristic bridge case and spatiotemporal ground motion from the SMART-1 array, are employed. These analyses confirm that in parametric configurations where the first mode is anti-symmetrical the error between MSE and ISE is often larger. This confirms the utility of geometry only modal and bounding analyses in identifying critical regions. These critical parametric cases of a first mode that is anti-symmetrical correspond to shallow valleys with a central rise. In these cases it is recommended that both ISE and MSE analyses should be employed to be conservative.
How to encourage innovation failure knowledge sharing in virtual research organization: an incentive mechanism based on game theory
Authors: Xiong Zhuang , Wang Pengju , Wu Chengxia 
Published: January 2021

AbstractInnovation failure knowledge sharing plays an important role in reducing the probability of repeated failure of subsequent innovation and improving innovation ability of virtual research organization. However, it is very difficult for members to actively share the innovation failure knowledge without incentives. To promote the sharing behavior of innovation failure knowledge in virtual research organization, by using game theory, considering the risk aversion degree of members and the negative effect of fault-tolerance environment, the incentive model of innovation failure knowledge sharing of virtual research organization was constructed, the incentive relationship of innovation failure knowledge sharing between organization and its members under the influence of different states was analyzed, and the theoretical model was simulated and verified through a case study from China. Results show that: (1) without considering the negative effect of fault-tolerant environment, the optimal incentive coefficient of innovation failure knowledge sharing is positively related to the shareable rate and the transformation ability of innovation failure knowledge of members, and negatively related to the sharing cost and risk aversion degree of members; (2) considering the negative effect of fault-tolerant environment, virtual research organization should make a corresponding modification of sharing incentive intensity according to the estimation of tolerance degree to fault-tolerant environment by itself and its members, so as to reduce the knowledge input of organization. The findings obtained from this study provide a novel idea and method for the design of incentive mechanism of innovation failure knowledge sharing of virtual research organization.