bluuebunny/crossref_metadata_2025 huggingface dataset:
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

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

This 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

We 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

Over 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

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

We 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

Der 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

There 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

This 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

Innovation 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.
A multistep approach to improving connectivity and co-use of spatial ecological networks in cities
Authors: Beaujean Simon , Nor Amal Najihah Muhamad , Brewer Tim , Zamorano Juan Gallego , Dumitriu Alex Cristina , Harris Jim , Corstanje Ron
Published: January 2021

Context

Ecological networks are systems of interconnected components that support biodiversity, ecological processes and ecosystem services. Such structures play a crucial role for nature conservation and people well-being in anthropogenic landscapes. Assessing connectivity by using efficient models and metrics is a sine qua non condition to preserve and improve appropriately these ecological networks.

Objectives

This study aims to present a novel methodological approach to assess and model connectivity for species conservation (Bufo calamita; the natterjack toad) and human recreation in the city.

Methods

The study used a combination least cost and circuit models to identify priority corridors in the City of Liège, Belgium. Green areas, habitats and relevant movement parameters were derived based on existing studies around (i) the occurrence, ecology and biology of the natterjack toad and (ii) human behavioural studies on urban pedestrians. Combining the two models allowed the assessment of connectivity for both species via two different metrics visualised using priority corridors on maps.

Results

The connectivity assessments identified lack of connectivity as the potential route to extinction of natterjack toads at one of the source sites.

Conclusions

This study provides examples of how combining least cost and circuit models can contribute to the improvement of urban ecological networks and demonstrates the usefulness of such models for nature conservation and urban planning.
The Balloon-Borne Investigation of Temperature and Speed of Electrons in the Corona (BITSE): Mission Description and Preliminary Results
Authors: Gopalswamy N. , Newmark J. , Yashiro S. , Mäkelä P. , Reginald N. , Thakur N. , Gong Q. , Kim Y.-H. , Cho K.-S. , Choi S.-H. , Baek J.-H. , Bong S.-C. , Yang H.-S. , Park J.-Y. , Kim J.-H. , Park Y.-D. , Lee J.-O. , Kim R.-S. , Lim E.-K.
Published: January 2021

We report on the Balloon-borne Investigation of Temperature and Speed of Electrons in the corona (BITSE) mission launched recently to observe the solar corona from $\approx 3$
≈
3
 Rs to 15 Rs at four wavelengths (393.5, 405.0, 398.7, and 423.4 nm). The BITSE instrument is an externally occulted single stage coronagraph developed at NASA’s Goddard Space Flight Center in collaboration with the Korea Astronomy and Space Science Institute (KASI). BITSE used a polarization camera that provided polarization and total brightness images of size $1024 \times 1024$
1024
×
1024
pixels. The Wallops Arc Second Pointer (WASP) system developed at NASA’s Wallops Flight Facility (WFF) was used for Sun pointing. The coronagraph and WASP were mounted on a gondola provided by WFF and launched from the Fort Sumner, New Mexico station of Columbia Scientific Balloon Facility (CSBF) on September 18, 2019. BITSE obtained 17,060 coronal images at a float altitude of $\approx \mbox{128,000}$
≈
128,000
feet ($\approx 39$
≈
39
 km) over a period of $\approx 4$
≈
4
 hrs. BITSE flight software was based on NASA’s core Flight System, which was designed to help develop flight quality software. We used EVTM (Ethernet Via Telemetry) to download science data during operations; all images were stored on board using flash storage. At the end of the mission, all data were recovered and analyzed. Preliminary analysis shows that BITSE imaged the solar minimum corona with the equatorial streamers on the east and west limbs. The narrow streamers observed by BITSE are in good agreement with the geometric properties obtained by the Solar and Heliospheric Observatory (SOHO) coronagraphs in the overlapping physical domain. In spite of the small signal-to-noise ratio ($\approx 14$
≈
14
) we were able to obtain the temperature and flow speed of the western steamer. In the heliocentric distance range 4 – 7 Rs on the western streamer, we obtained a temperature of $\approx 1.0\pm 0.3$
≈
1.0
±
0.3
 MK and a flow speed of $\approx 260$
≈
260
 km s−1 with a large uncertainty interval.
Social isolation and connection in adolescents with cancer and survivors of childhood cancer: A systematic review
Authors: Pahl Daniel A. , Wieder Matthew S. , Steinberg Dara M.
Published: January 2021

Introduction

Cancer may cause significant disruptions in normal adolescent development particularly in social domains. Both treatment and survivorship pose challenges to fostering social connections. To better understand these challenges, we conducted a systematic literature review of the experience of social isolation and connectedness in adolescents with cancer and adolescent survivors of childhood cancer.

Methods

A systematic review of the scientific literature was conducted following PRISMA Guidelines. Eligible articles included original peer‐reviewed research published in English between January 2000 and April 2020 that reported on social domains of patients and survivors of cancer between the ages of 10–21. Initial database search identified 4606 articles with 43 studies meeting inclusion criteria.

Results

Results were synthesized into four domains: (1) the prevalence of connectedness/isolation; (2) risk factors associated with social isolation; (3) protective factors against social isolation; (4) the impact of social isolation on psychological health. Overall, adolescent patients and survivors of cancer have satisfactory social connectedness. However, certain subgroups including those with central nervous system tumors are at higher risk of social isolation.

Conclusions

In general, adolescent cancer patients and survivors report levels of social connectedness consistent with healthy adolescent population norms. The risk and protective factors identified in this review may help serve as important indicators for psychosocial screening and interventions. These findings are particularly relevant in the COVID‐19 era as all adolescents face challenges to social connections and psychosocial development.
Emotional foundations of capability development: an exploration in the SME context
Authors: Kars-Unluoglu Selen , Kevill Alex
Published: January 2021

Research uncovering the behavioural and cognitive foundations of capability development has gained traction in recent years. However, the emotional foundations of capability development have not been adequately addressed. This is an important gap; if emotions impact decisions and actions of key organisational actors, this suggests an influence on capability development processes in organisations, with implications for their survival and evolution. In this paper, we therefore explore ‘how do the emotions of key strategists enable and/or hinder capability development?’ Our in-depth qualitative research, based on five small- and medium-sized enterprises (SMEs), shows that emotions of key strategists, including emotional tensions and ambivalence, have multi-faceted effects on capability development depending on the activation level of pleasant and unpleasant emotions experienced. This adds to extant understanding of idiosyncratic foundations of capability development and extends conversations regarding the internal dynamics behind organisational survival and evolution.
Oldest Dryas hydroclimate reorganization in the eastern Iberian Peninsula after the iceberg discharges of Heinrich Event 1
Authors: Pérez-Mejías Carlos , Moreno Ana , Bernal-Wormull Juan , Cacho Isabel , Osácar M. Cinta , Edwards R. Lawrence , Cheng Hai
Published: January 2021

This study examines the first precisely dated and temporally highly resolved speleothem record from Iberia that reconstructs the Oldest Dryas (OD). The onset of cold conditions in the study area, contemporary with the beginning of Heinrich Stadial 1, is recorded at 18.13 ± 0.08 ka, with a pronounced drop of 6.1‰ in δ13C in 250 years. Henceforth, stadial conditions depict a period of instability in the Atlantic Meridional Overturning Circulation, peaking in freshwater input from iceberg melting during Heinrich Event 1. Anomalies in the δ18O of the stalagmite attributed to such a freshwater event are found from 16.17 to 15.89 ka. Such absolute dates given to the onset of the OD in Iberia and to the main iceberg discharges are reliable anchor points for non-absolute chronologies. Two periods are identified in the OD: OD-a (18.13–16.17 ka) is characterized by wet conditions and a faster growth rate, and OD-b (15.89–14.81 ka) exhibits relative dryness and a slower growth rate. The sudden release of fresh water is considered to be the reason for the disruption of rainfall patterns in eastern Iberia. The present study also highlights the existence of heterogeneous and complex hydrological conditions during the OD in Iberia when both Atlantic and Mediterranean realms are considered.
Migration, Identity, and Colonial Fantasies in a Fifth-Century Story Collection
Authors: Tian Xiaofei
Published: January 2021

At the turn of the fifth century, a story about a man contesting real estate with a ghost circulated in several different versions in South China. In one of the versions, a young man discovered three lacquer coffins when digging a tomb for his deceased father and had the coffins reburied elsewhere. That night, he dreamed of Lu Su 魯肅 (172–217), the powerful minister in the southern Kingdom of Wu, who angrily announced that he would exact revenge. He also dreamed of his late father, who told him that Lu Su was fighting with him over the gravesite. Later, the young man found copious blood on his father's seating mat.
Captives, Deserters, and Exiles: Control of Migrant Mobility in the Northern Wei Period (386–534 CE)
Authors: Huang Wen-Yi
Published: January 2021

Controlling the physical movement of people was a well-established tradition throughout imperial China. Scholars have argued that the Qin (221–206 BCE) and Han (206 BCE–220 CE) empires required their subjects to register personal information, including their place of residence, with local governments, and both empires exerted strict control over the flows of officials and those who traveled for personal reasons within the territory, mainly through checkpoints and travel documents. Recent studies have also shown that forced resettlement was a common means of mobility regulation. Ancient states, from the Qin to the Mongol empire, achieved their imperial goals through a variety of measures, one of the most important of which was the relocation of subjects and conquered peoples whenever and wherever they saw fit.
Temperature, Disease, and Death in London: Analyzing Weekly Data for the Century from 1866 to 1965
Authors: Hanlon W. Walker , Hansen Casper Worm , Kantor Jake
Published: January 2021

Using novel weekly mortality data for London spanning 1866-1965, we analyze the changing relationship between temperature and mortality as the city developed. Our main results show that warm weeks led to elevated mortality in the late nineteenth century, mainly due to infant deaths from digestive diseases. However, this pattern largely disappeared after WWI as infant digestive diseases became less prevalent. The resulting change in the temperature-mortality relationship meant that thousands of heat-related deaths—equal to 0.9-1.4 percent of all deaths— were averted. These findings show that improving the disease environment can dramatically alter the impact of high temperature on mortality.
Plasma sheath and presheath development near a partially reflective surface
Authors: Breizman Boris N. , Kiramov Dmitrii I.
Published: January 2021

This work addresses one-dimensional evolution of a collisionless plasma next to a solid surface that is immersed into the plasma instantaneously. In particular, we consider how the self-similar rarefaction wave (Allen & Andrews, J. Plasma Phys., vol. 4, 1970, pp. 187–194) establishes dynamically and how the electron reflection from the surface modifies the structure of the rarefaction wave and the Debye sheath. We demonstrate that a sufficiently strong reflection eliminates the Debye sheath and changes the wall potential and the plasma flow parameters significantly. The paper presents numerical results that illustrate the developed analytical theory.
The role of depressive symptoms and symptom dimensions in actigraphy-assessed sleep, circadian rhythm, and physical activity
Authors: Difrancesco Sonia , Penninx Brenda W. J.H. , Riese Harriëtte , Giltay Erik J. , Lamers Femke
Published: January 2021

Background

Considering the heterogeneity of depression, distinct depressive symptom dimensions may be differentially associated with more objective actigraphy-based estimates of physical activity (PA), sleep and circadian rhythm (CR). We examined the association between PA, sleep, and CR assessed with actigraphy and symptom dimensions (i.e. mood/cognition, somatic/vegetative, sleep).

Methods

Fourteen-day actigraphy data of 359 participants were obtained from the Netherlands Study of Depression and Anxiety. PA, sleep, and CR estimates included gross motor activity (GMA), sleep duration (SD), sleep efficiency (SE), relative amplitude between daytime and night-time activity (RA) and sleep midpoint. The 30-item Inventory of Depressive Symptomatology was used to assess depressive symptoms, which were categorised in three depression dimensions: mood/cognition, somatic/vegetative, and sleep.

Results

GMA and RA were negatively associated with higher score on all three symptom dimensions: mood/cognition (GMA: β = −0.155, p < 0.001; RA: β = −0.116, p = 0.002), somatic/vegetative (GMA: β = −0.165, p < 0.001; RA: β = −0.133, p < 0.001), sleep (GMA: β = −0.169, p < 0.001; RA: β = −0.190, p < 0.001). The association with sleep was more pronounced for two depression dimensions: longer SD was linked to somatic/vegetative (β = 0.115, p = 0.015) dimension and lower SE was linked to sleep (β = −0.101, p = 0.011) dimension.

Conclusion

As three symptom dimensions were associated with actigraphy-based low PA and dampened CR, these seem to be general indicators of depression. Sleep disturbances appeared more linked to the somatic/vegetative and sleep dimensions; the effectiveness of sleep interventions in patients reporting somatic/vegetative symptoms may be explored, as well as the potential of actigraphy to monitor treatment response to such interventions.
PHILIP II OF SPAIN AND TRAJAN: HISTORY OF A SPECIAL UNDELIVERED GIFT AND OF THE RECEPTION OF TRAJAN'S COLUMN
Authors: Brunetti Marco
Published: January 2021

The Pitti crystal column, preserved at the Uffizi Museum, is one of the most refined glyptic objects of the Renaissance age. Owing to its decorative system on a miniature scale, the significance of many of its scenes has remained unclear, and hence, as a consequence, so have its function, iconological message, the meaning of its all'antica style, and its intended recipient. Using detailed images of each engraved scene, this paper shows how the decorative system of the artefact (originally a mirror) is related to King Philip II of Spain (1527–1598). The entire decoration was designed to eulogize Philip II, and especially the Battle of Saint-Quentin (1557), and his consequent control over some Italian lands (Milan, Naples, Sicily and Sardinia) after the Treaty of Cateau-Cambrésis (1559). The paper investigates the reasons why Trajan's Column was chosen as an inspirational model for the Pitti column and how such an ancient model was re-elaborated and renewed through the combination of other elements that came from a wider antiquarian all'antica repertoire. In this way, it is possible to show that this valuable artefact is a clear example of how the use of all'antica style in the Renaissance was not purely referencing a glorious past, but was adapted to the use of the object itself.
Life satisfaction among older adults in urban China: does gender interact with pensions, social support and self-care ability?
Authors: Chen Mengni , Fu Yuanyuan , Chang Qingsong
Published: January 2021

In urban China, the social welfare system and the family structure have changed dramatically, while gender norms are still deep-rooted, particularly among older adults. Under this social, demographic and cultural context, this study aims to take a gender-specific perspective to investigate whether and how gender moderates the roles of pensions, social support and self-care ability on older adults’ life satisfaction. Based on the survey data collected from 2,047 older adults aged 65 years and over in urban China in 2018, multiple linear regressions were applied to explore the moderation effects. The results show that the pension is important to older adults’ life satisfaction regardless of gender. For social support, the association between family support and life satisfaction is stronger for older men than for older women; interdependent social support, especially being a confidant, matters more to women than to men. The interaction between self-care ability and gender reveals some interesting patterns: self-care ability is found to have a positive association with women's life satisfaction but a negative association with men's. This study contributes to the existing literature by demonstrating how gender intertwines with the most important factors of older adult's life satisfaction in China – a society with strong gender norms and a patriarchal culture. These findings could be relevant to other Asian societies.
Research into practice: CLIL in South America
Authors: Banegas Darío Luis
Published: January 2021

This paper discusses three relationships between content and language integrated learning (CLIL) research and practice in the context of South America. The first relationship focuses on research with successful results in the areas of language learning motivation and intercultural communicative competence and citizenship. The second relationship discusses research which has yielded mixed results to support language learning and cognitive development. The last relationship suggests what areas deserve special attention to offer further support to teachers involved in CLIL provision. The following areas are addressed: teacher-made CLIL materials, language and content gains, L1-L2 (first language, second language) curriculum design, and inclusion. In conclusion, I assert that CLIL in South America can be invigorated if researchers and educators carry out research, preferably in collaboration, that recognises, maximises and improves CLIL in practice. I also suggest that the CLIL community in South America may engage in creating CLIL models and conceptual frameworks that respond to the particularities of their settings with the aim of making CLIL context-responsive and sustainable.
Position-Based Fractional-Order Impedance Control of a 2 DOF Serial Manipulator
Authors: Kizir Selçuk , Elşavi Ali
Published: January 2021

Impedance control is one of the interaction and force control methods that has been widely applied in the research of robotics. In this paper, a new position-based fractional-order impedance control scheme is proposed and applied to a 2 DOF serial manipulator. An RR robot manipulator with full arm dynamics and its environment were designed using Matlab/Simulink. The position control of the manipulator was utilized based on computed torque control to cancel out the nonlinearities existing on the dynamic model of the robot. Parameters of classical impedance controller (CIC) and proposed fractional-order impedance controller (FOIC) were optimized in order to minimize impact forces for comparison of the results in three conditions. In CIC condition: three constant parameters of the impedance controller were optimized: in Frac_λμ condition: Only non-integer parameters of the FOIC were re-optimized after the parameters in CIC had been accepted, and in Frac_all condition: all parameters of the FOIC were re-optimized. In order to show the effectiveness of the proposed method, simulations were conducted for all cases and performance indices were computed for the interaction forces. Results showed that impacts were reduced with an improvement of 26.12% from CIC to Frac_ λμ and an improvement of 47.21% from CIC to Frac_all. The proposed scheme improves the impedance behavior and robustness showing better impact absorption performance, which is needed in many challenging robotic tasks and intelligent mechatronic devices.
Investigating sea urchin densities critical to macroalgal control on degraded coral reefs
Authors: Dajka Jan-Claas , Beasley Victoria , Gendron Gilberte , Graham Nicholas AJ
Published: January 2021

There is an assumption that tropical sea urchins are macroalgal grazers with the ability to control macroalgal expansion on degraded coral reefs. We surveyed abundances ofEchinothrix calamaris, an urchin species common in the western Indian Ocean on 21 reefs of the inner Seychelles and predicted their density using habitat predictors in a modelling approach. Urchin densities were greatest on patch reef habitat types and declined with increasing macroalgal cover. Next, we experimentally investigated the macroalgae-urchin relationship by penning two sea urchin densities on macroalgal fields. Over six weeks, the highest density treatment (4.44 urchins m−2) cleared 13% of macroalgal cover. This moderate impact leads us to conclude that controlling macroalgal expansion is not likely to be one of the main functions ofE. calamarisin the inner Seychelles given the current densities we found in our surveys (mean: 0.02 urchins m−2, maximum: 0.16 urchins m−2).
Gonadal and adrenal hormones interact with pubertal maturation to predict depressive symptoms in a group of high-school females
Authors: Chafkin Julia E. , Yeager David S. , O'Brien Joseph M. , Lee Hae Yeon , McAfee Ciara A. , Josephs Robert A.
Published: January 2021

Adolescent females are at elevated risk for the development of depression. In this study, we addressed two questions: Are pubertal hormones associated with adolescent mental health? Might this association depend on pubertal development? We tested the hypothesis that estradiol, which has been associated with adolescent social sensitivity, might interact with pubertal stage to predict depression risk at three time points in ninth and tenth grade. Hormones and pubertal development were measured ninth-grade females. Linear regression analyses were used to predict fall ninth-grade (N = 79), spring ninth-grade (N = 76), and spring tenth-grade (N = 67) Children's Depression Inventory (CDI) scores. The hypothesized model was not statistically significant, but exploratory analyses revealed that two- and three-way interactions incorporating estradiol, puberty (stage and perceived onset), and cortisol predicted current and future CDI scores. Our exploratory model did not predict changes in CDI but did account for future (spring of ninth grade) CDI scores. Specifically, estradiol was positively correlated with fall and spring ninth-grade depressive symptoms in participants with high cortisol who also reported earlier stages and later perceived onset of pubertal development. These findings suggest that hormones associated with sensitivity to the social environment deserve consideration in models of adolescent depression risk.
Postponing production exponentially enhances the molecular memory of a stochastic switch
Authors: BOKES PAVOL
Published: January 2021

Delayed production can substantially alter the qualitative behaviour of feedback systems. Motivated by stochastic mechanisms in gene expression, we consider a protein molecule which is produced in randomly timed bursts, requires an exponentially distributed time to activate and then partakes in positive regulation of its burst frequency. Asymptotically analysing the underlying master equation in the large-delay regime, we provide tractable approximations to time-dependent probability distributions of molecular copy numbers. Importantly, the presented analysis demonstrates that positive feedback systems with large production delays can constitute a stable toggle switch even if they operate with low copy numbers of active molecules.
Effect of acute lower respiratory tract infection on pulmonary artery pressure in children with post-tricuspid left-to-right shunt
Authors: Sachdeva Sakshi , Kothari Shyam S. , Gupta Saurabh K. , Ramakrishnan Sivasubramanian , Saxena Anita
Published: January 2021

We sought to examine the influence of clinically severe lower respiratory tract infection on pulmonary artery pressure in children having CHD with post-tricuspid left-to-right shunt, as it may have physiological and clinical implications. In a prospective single-centre observational study, 45 children with post-tricuspid left-to-right shunt and clinically severe lower respiratory tract infection were evaluated during the illness and 2 weeks after its resolution. Pulmonary artery systolic pressure was estimated non-invasively using shunt gradient by echocardiography and systolic blood pressure measured non-invasively.

Median pulmonary artery systolic pressure during lower respiratory tract infection was only mildly (although statistically significantly) elevated during lower respiratory tract infection [60 (42–74) versus 53 (40–73) mmHg, (p < 0.0001)]. However, clinically significant change in pulmonary artery systolic pressure defined as the increase of >10 mmHg was present in only 9 (20%) patients. In the absence of hypoxia or acidosis, only a small minority (9%, n = 4) showed significant pulmonary artery systolic pressure rise >10 mmHg. In the absence of hypoxia or acidosis, severe lower respiratory tract infection in patients with acyanotic CHD results in only mild elevation of pulmonary artery systolic pressure in most of the patients.
Mismatches Between the Number of Installed Automated External Defibrillators and the Annual Rate of Automated External Defibrillator Use Among Places
Authors: Oh Je Hyeok , Cho Gyu Chong , Ryoo Seung Mok , Han So Hyun , Woo Seon Hee , Jang Yong Soo , Cho Youngsuk , Sim Minseob , Kim Oh Hyun
Published: January 2021

Aim:

In South Korea, the law concerning automated external defibrillators (AEDs) states that they should be installed in specific places including apartment complexes. This study was conducted to investigate the current status and effectiveness of installation and usage of AEDs in South Korea.

Methods:

Installation and usage of AEDs in South Korea is registered in the National Emergency Medical Center (NEMC) database. Compared were the installed number, usage, and annual rate of AED use according to places of installation. All data were obtained from the NEMC database.

Results:

After excluding AEDs installed in ambulances or fire engines (n = 2,003), 36,498 AEDs were registered in South Korea from 1998 through 2018. A higher number of AEDs were installed in places required by the law compared with those not required by the law (20,678 [56.7%] vs. 15,820 [43.3%]; P <.001). Among them, 11,318 (31.0%) AEDs were installed in apartment complexes. The overall annual rate of AED use was 0.38% (95% CI, 0.33-0.44). The annual rate of AED use was significantly higher in places not required by the law (0.62% [95% CI, 0.52-0.72] versus 0.21% [95% CI, 0.16-0.25]; P <.001). The annual rate of AED use in apartment complexes was 0.13% (95% CI, 0.08-0.17).

Conclusion:

There were significant mismatches between the number of installed AEDs and the annual rate of AED use among places. To optimize the benefit of AEDs in South Korea, changes in the policy for selecting AED placement are needed.