bluuebunny/crossref_metadata_2025_split huggingface dataset:
Three-dimensional numerical and experimental study of fracture saturation in panel paintings
Authors: Abdollahzadeh Jamalabadi Mohammad Yaghoub , Zabari Noemi , Bratasz Łukasz 
Published: September 2021

AbstractPanel paintings—complex multi-layer structures consisting of wood support and a paint layer composed of a preparatory layer of gesso, paints, and varnishes—are among the category of cultural objects most vulnerable to relative humidity fluctuations and frequently found in museum collections. The current environmental specifications in museums have been derived using the criterion of crack initiation in an undamaged, usually new gesso layer laid on wood. In reality, historical paintings exhibit complex crack patterns called craquelures. The present paper analyses the structural response of a paint layer with a virtual network of rectangular cracks under environmental loadings using a three-dimensional model of a panel painting. Two modes of loading are considered—one induced by one-dimensional moisture response of wood support, termed the tangential loading, and the other isotropic induced by drying shrinkage of the gesso layer. The superposition of the two modes is also analysed. The modelling showed that minimum distances between cracks parallel to the wood grain depended on the gesso stiffness under the tangential loading. Despite a nonzero Poisson’s ratio, gesso cracks perpendicular to the wood grain could not be generated by the moisture response of the wood support. The isotropic drying shrinkage of gesso produced cracks that were almost evenly spaced in both directions. The modelling results were cross-checked with crack patterns obtained on a mock-up of a panel painting exposed to several extreme environmental variations in an environmental chamber.
High frequency of prospecting for informed dispersal and colonisation in a social species at large spatial scale
Authors: Oro Daniel , Bécares Juan , Bartumeus Frederic , Arcos José Manuel 
Published: September 2021

AbstractAnimals explore and prospect space searching for resources and individuals may disperse, targeting suitable patches to increase fitness. Nevertheless, dispersal is costly because it implies leaving the patch where the individual has gathered information and reduced uncertainty. In social species, information gathered during the prospection process for deciding whether and where to disperse is not only personal but also public, i.e. conspecific density and breeding performance. In empty patches, public information is not available and dispersal for colonisation would be more challenging. Here we study the prospecting in a metapopulation of colonial Audouin’s gulls using PTT platform terminal transmitters tagging for up to 4 years and GPS tagging during the incubation period. A large percentage of birds (65%) prospected occupied patches; strikingly, 62% of prospectors also visited empty patches that were colonised in later years. Frequency and intensity of prospecting were higher for failed breeders, who dispersed more than successful breeders. Prospecting and dispersal also occurred mostly to neighbouring patches where population density was higher. GPSs revealed that many breeders (59%) prospected while actively incubating, which suggests that they gathered information before knowing the fate of their reproduction. Prospecting may be enhanced in species adapted to breed in ephemeral habitats, such as Audouin’s gulls. Interestingly, none of the tracked individuals colonised an empty patch despite having prospected over a period of up to three consecutive years. Lack of public information in empty patches may drive extended prospecting, long time delays in colonisation and non-linear transient phenomena in metapopulation dynamics and species range expansion.
Multi-species prey dynamics influence local survival in resident and wintering generalist predators
Authors: Oro Daniel , Sanz-Aguilar Ana , Carbonell Francesc , Grajera Joan , Torre Ignasi 
Published: September 2021

AbstractStochasticity in food availability influences vital rates such as survival and fertility. Life-history theory predicts that in long-lived organisms, survival should be buffered against environmental stochasticity showing little temporal variability. Furthermore, to optimize survival prospects, many animal species perform migrations to wintering areas where food availability is larger. Species with large latitudinal distribution ranges may show populations that migrate and others that are resident, and they may co-occur in winter. One example of these species is the predatory raptor buzzardButeo buteo. Here, we test whether temporal variability in the density of five small mammal species of prey inhabiting different habitats (shrubland and forests) influences local annual survival of buzzards in a wintering area depending on their age and residency status (residents versus wintering individuals). We found that prey density explained a considerable amount of annual changes in local survival, which was higher for older and resident birds. This difference in local survival likely corresponded to philopatry to the wintering area, which was larger for residents and increased when prey density was larger. The total density of prey inhabiting open shrublands was the variable explaining more variance in temporal variability of local survival, even though the study area is mostly occupied by woodlands. Temporal population dynamics of the different small mammals inhabiting shrublands were not synchronous, which suggests that buzzards preyed opportunistically on the most abundant prey each winter. Generalist predation may buffer the impact of resource unpredictability for pulsed and asynchronous prey dynamics, typical of small mammals in winter.
Korevaar–Schoen’s energy on strongly rectifiable spaces
Authors: Gigli Nicola , Tyulenev Alexander 
Published: September 2021

AbstractWe extend Korevaar–Schoen’s theory of metric valued Sobolev maps to cover the case of the source space being an $$\mathsf{RCD}$$
RCD
space. In this situation it appears that no version of the ‘subpartition lemma’ holds: to obtain both existence of the limit of the approximated energies and the lower semicontinuity of the limit energy we shall rely on:

the fact that such spaces are ‘strongly rectifiable’ a notion which is first-order in nature (as opposed to measure-contraction-like properties, which are of second order). This fact is particularly useful in combination with Kirchheim’s metric differentiability theorem, as it allows to obtain an approximate metric differentiability result which in turn quickly provides a representation for the energy density,

the differential calculus developed by the first author which allows, thanks to a representation formula for the energy that we prove here, to obtain the desired lower semicontinuity from the closure of the abstract differential.

When the target space is $$\mathsf{CAT}(0)$$

CAT
(
0
)

we can also identify the energy density as the Hilbert-Schmidt norm of the differential, in line with the smooth situation.
Variational formulas for submanifolds of fixed degree
Authors: Citti Giovanna , Giovannardi Gianmarco , Ritoré Manuel 
Published: September 2021

AbstractWe consider in this paper an area functional defined on submanifolds of fixed degree immersed into a graded manifold equipped with a Riemannian metric. Since the expression of this area depends on the degree, not all variations are admissible. It turns out that the associated variational vector fields must satisfy a system of partial differential equations of first order on the submanifold. Moreover, given a vector field solution of this system, we provide a sufficient condition that guarantees the possibility of deforming the original submanifold by variations preserving its degree. As in the case of singular curves in sub-Riemannian geometry, there are examples of isolated surfaces that cannot be deformed in any direction. When the deformability condition holds we compute the Euler–Lagrange equations. The resulting mean curvature operator can be of third order.
Does stereoscopic imaging improve the memorization of medical imaging by neurosurgeons? Experience of a single institution
Authors: Schlinkmann Nicolas , Khakhar Rutvik , Picht Thomas , Piper Sophie K. , Fekonja Lucius S. , Vajkoczy Peter , Acker Gueliz 
Published: September 2021

AbstractStereoscopic imaging has increasingly been used in anatomical teaching and neurosurgery. The aim of our study was to analyze the potential utility of stereoscopic imaging as a tool for memorizing neurosurgical patient cases compared to conventional monoscopic visualization. A total of 16 residents and 6 consultants from the Department of Neurosurgery at Charité – Universitätsmedizin Berlin were recruited for the study. They were divided into two equally experienced groups. A comparative analysis of both imaging modalities was conducted in which four different cases were assessed by the participants. Following the image assessment, two questionnaires, one analyzing the subjective judgment using the 5-point Likert Scale and the other assessing the memorization and anatomical accuracy, were completed by all participants. Both groups had the same median year of experience (5) and stereoacuity (≤ 75 s of arc). The analysis of the first questionnaire demonstrated significant subjective superiority of the monoscopic imaging in evaluation of the pathology (median: monoscopic: 4; stereoscopic: 3; p = 0.020) and in handling of the system (median: monoscopic: 5; stereoscopic: 2; p < 0.001). The second questionnaire showed that the anatomical characterization of the pathologies was comparable between both visualization methods. Most participants rated the stereoscopic visualization as worse compared to the monoscopic visualization, probably due to a lack of familiarity with the newer technique. Stereoscopic imaging, however, was not objectively inferior to traditional monoscopic imaging for anatomical comprehension. Further methodological developments and incorporation in routine clinical workflows will most likely enhance the usability and acceptance of stereoscopic visualization.
Complementarity Modeling of a Ramsey-Type Equilibrium Problem with Heterogeneous Agents
Authors: Frerick Leonhard , Müller-Fürstenberger Georg , Schmidt Martin , Späth Max 
Published: September 2021

AbstractWe contribute to the field of Ramsey-type equilibrium models with heterogeneous agents. To this end, we state such a model in a time-continuous and time-discrete form, which in the latter case leads to a finite-dimensional mixed complementarity problem. We prove the existence of solutions of the latter problem using the theory of variational inequalities and present further properties of its solutions. Finally, we compute the growth dynamics in a calibrated model in which households differ with respect to their relative risk aversion, their discount factors, their initial wealth, and with respect to their interest rates on savings.
Well-being and its relationship with sports and physical activity of students during the coronavirus pandemic
Authors: Pietsch Stefanie , Linder Stefanie , Jansen Petra 
Published: September 2021

AbstractThe main goal of this correlational study is to examine the changes in the amount and type of physical activity of students of various study programs during the coronavirus pandemic. Furthermore, the motives for these changes as well as their relationship with general well-being are investigated. Therefore, 243 students (sport science, humanities, natural sciences) answered questions concerning (a) the amount and type of their physical activity before and during the pandemic, (b) their well-being and (c) their optimism/pessimism. The main result of the study is that the type and the motives for sports and physical activity changed for the study participants during the coronavirus pandemic: Team sports and swimming decreased, while individual sports and physical activity not associated with a sports club/business and with digital media increased. In this study the difference in sports and physical activity seemed to be related to well-being, especially for the students of sport science and humanities. To conclude the study indicated that a change occurred in the type of sports and physical activity as well as change in the motives for physical exercise in students during the pandemic.
Resilience of environmental policy amidst the rise of conservative populism
Authors: Mostafavi Nariman , Fiocchi João , Dellacasa Manuel García , Hoque Simi 
Published: September 2021

AbstractSustainability has for long been promoted as a medium for social and economic development, one that focuses on constant availability of natural assets and ecological amenities. By questioning the possibility of reaching a balanced and sustainable state of functioning for social-ecological systems, resilience improves the static framework of sustainability by acknowledging non-linear behavior of complex systems, inevitability of change, and consistent presence of uncertainty. At the core of sustainable development, environmental policy is embedded in the socio-spatial structures that constantly re-organize and breed uncertainty, such as political, economic, and climate uncertainty. These uncertainties create episodes of instability that shock the entire system including the structures of environmental protection. In this article, focusing on the aftermath of 2016 US presidential election and 2018 general election in Brazil, both broadly recognized as political shocks, we highlight the vulnerabilities of environmental protection structures to the rise of conservative populist movements. We attribute these vulnerabilities, partially, to the superiority of market-based instruments, as well as apolitical understandings of resilience under neoliberalism that overlook political instabilities and socio-spatial outcomes of neoliberal restructuring projects. In our assessment, political unpreparedness of sustainability against the right-wing onslaught in the US and Brazil further underlines the need for resilience theory to incorporate sources of political instability in order to protect the environment.
Evaluation of sonication on stability-indicating properties of optimized pilocarpine hydrochloride-loaded niosomes in ocular drug delivery
Authors: Owodeha-Ashaka Kruga , Ilomuanya Margaret O. , Iyire Affiong 
Published: September 2021

AbstractNiosomes are increasingly explored for enhancing drug penetration and retention in ocular tissues for both posterior and anterior eye delivery. They have been employed in encapsulating both hydrophilic and hydrophobic drugs, but their use is still plagued with challenges of stability and poor entrapment efficiency particularly with hydrophilic drugs. As a result, focus is on understanding the parameters that affect their stability and their optimization for improved results. Pilocarpine hydrochloride (HCl), a hydrophilic drug is used in the management of intraocular pressure in glaucoma. We aimed at optimizing pilocarpine HCl niosomes and evaluating the effect of sonication on its stability-indicating properties such as particle size, polydispersity index (PDI), zeta potential and entrapment efficiency. Pilocarpine niosomes were prepared by ether injection method. Composition concentrations were varied and the effects of these variations on niosomal properties were evaluated. The effects of sonication on niosomes were determined by sonicating optimized drug-loaded formulations for 30 min and 60 min. Tween 60 was confirmed to be more suitable over Span 60 for encapsulating hydrophilic drugs, resulting in the highest entrapment efficiency (EE) and better polydispersity and particle size indices. Optimum sonication duration as a process variable was determined to be 30 min which increased EE from 24.5% to 42% and zeta potential from (−)14.39 ± 8.55 mV to (−)18.92 ± 7.53 mV. In addition to selecting the appropriate surfactants and varying product composition concentrations, optimizing sonication parameters can be used to fine-tune niosomal properties to those most desirable for extended eye retainment and maintenance of long term stability.
Effect of a high-fat diet and chromium on hormones level and Cr retention in rats
Authors: Stępniowska A. , Tutaj K. , Juśkiewicz J. , Ognik K. 
Published: September 2021

Abstract
Aims
The aim of the study was to determine how the administration of a high-fat diet supplemented with various forms of chromium to rats affects accumulation of this element in the tissues and levels of leptin, ghrelin, insulin, glucagon, serotonin, noradrenaline and histamine, as well as selected mineral elements.

Methods
The experiment was conducted on 56 male Wistar rats, which were divided into 8 experimental groups. The rats received standard diet or high fat diet (HFD) with addition of 0.3 mg/kg body weight of chromium(III) picolinate (Cr-Pic), chromium(III)-methioninate (Cr-Met), or chromium nanoparticles (Cr-NP).

Results
Chromium in organic forms was found to be better retained in the body of rats than Cr in nanoparticles form. However, Cr-Pic was the only form that increased the insulin level, which indicates its beneficial effect on carbohydrate metabolism. In blood plasma of rats fed a high-fat diet noted an increased level of serotonin and a reduced level of noradrenaline. The addition of Cr to the diet, irrespective of its form, also increased the serotonin level, which should be considered a beneficial effect. Rats fed a high-fat diet had an unfavourable reduction in the plasma concentrations of Ca, P, Mg and Zn. The reduction of P in the plasma induced by supplementation with Cr in the form of Cr-Pic or Cr-NP may exacerbate the adverse effect of a high-fat diet on the level of this element.

Conclusion
A high-fat diet was shown to negatively affect the level of hormones regulating carbohydrate metabolism (increasing leptin levels and decreasing levels of ghrelin and insulin).
Biocompatible Multifunctional E-Skins with Excellent Self-Healing Ability Enabled by Clean and Scalable Fabrication
Authors: Lin Xiuzhu , Li Fan , Bing Yu , Fei Teng , Liu Sen , Zhao Hongran , Zhang Tong 
Published: September 2021

AbstractElectronic skins (e-skins) with an excellent sensing performance have been widely developed over the last few decades. However, wearability, biocompatibility, environmental friendliness and scalability have become new limitations. Self-healing ability can improve the long-term robustness and reliability of e-skins. However, self-healing ability and integration are hardly balanced in classical structures of self-healable devices. Here, cellulose nanofiber/poly(vinyl alcohol) (CNF/PVA), a biocompatible moisture-inspired self-healable composite, was applied both as the binder in functional layers and the substrate. Various functional layers comprising particular carbon materials and CNF/PVA were patterned on the substrate. A planar structure was beneficial for integration, and the active self-healing ability of the functional layers endowed self-healed e-skins with a higher toughness. Water served as both the only solvent throughout the fabrication process and the trigger of the self-healing process, which avoids the pollution and bioincompatibility caused by the application of noxious additives. Our e-skins could achieve real-time monitoring of whole-body physiological signals and environmental temperature and humidity. Cross-interference between different external stimuli was suppressed through reasonable material selection and structural design. Combined with conventional electronics, data could be transmitted to a nearby smartphone for post-processing. This work provides a previously unexplored strategy for multifunctional e-skins with an excellent practicality.
Towards a network theory of regulatory burden
Authors: Straughter Jeremy , Carley Kathleen 
Published: September 2021

AbstractGovernment overlap creates problems for the public and private sector across several government systems. Research suggests that overlap burdens the political and economic system by increasing costs in terms of money, time, and complexity, decreasing innovation and investment, and dampening economic growth. Previous research has identified frameworks for categorizing regulatory overlap. However, the literature has not considered factors that contribute to regulatory overlap nor effective methods for its reduction. This research introduces a proxy measure for regulatory overlap which measures the regulatory burden that a federal agency imposes within the regulatory system. This research proposes a network theory of regulatory burden which finds that burden is a function of network properties characterizing a federal agency’s position within the regulatory system. This research suggests that the federal government may reduce occurrences of regulatory overlap by managing its regulatory network and fostering collaboration among federal agencies within the regulatory system.
Ethical and legal responsibility for Artificial Intelligence
Authors: Henz Patrick 
Published: September 2021

Abstract“In civilized life, law floats in a sea of ethics”, a quote by the former Chief Justice of the United States, Earl Warren. In a democratic society, the constitution defines the country’s values, and the laws define the preferred or at least still tolerated behavior, making deviations sanctionable. As the society is in a continuous flow, also based on scientific and technical developments, law always lags behind. Until regulations can catch up, ethics has to lead society. In less democratic societies, the water gets polluted up to poisoned, ethical behavior may be against ruling law. As for the latter, Robin Hood was a thief, but for most parts of the population, a hero. The less transparent the water, the more difficult to adapt law to new developments. This includes direct corruption, but also unfaithful lobbying. This article discusses the “nature” of Artificial Intelligence, including the risks its posing, and who is responsible for systematic errors, from a moral, but also legal point.
Exploring Convolutional Recurrent architectures for anomaly detection in videos: a comparative study
Authors: Ravi Ambareesh , Karray Fakhri 
Published: September 2021

AbstractConvolutional Recurrent architectures are currently preferred for spatio-temporal learning tasks in videos to the 3D convolutional networks which accompany a huge computational burden and it is imperative to understand the working of different architectural configurations. But most of the current works on visual learning, especially for video anomaly detection, predominantly employ ConvLSTM networks and focus less on other possible variants of Convolutional Recurrent configurations for temporal learning which warrants a need to study the different possible variants to make informed, optimal design choices according to the nature of the application at hand. We explore a variety of Convolutional Recurrent architectures and the influence of hyper-parameters on their performance for the task of anomaly detection. Through this work, we also intend to quantify the efficiency of the architectures based on the trade-off between their performance and computational complexity. With comprehensive quantitative and visual evidence, we establish that the ConvGRU based configurations are the most effective and perform better than the popular ConvLSTM configurations on video anomaly detection tasks, in contrast to what is seen from the literature.