bluuebunny/crossref_metadata_2025 huggingface dataset:
Greener synthesis of lightweight, self‐standing PMMA/CoFe2O4 polymeric film for magnetic, electronic, and terahertz shielding applications
Authors: Mohamed Fathia , Ahmad Manal M. , Hameed Talaat A.
Published: January 2023

This work aims to develop a multifunctional PMMA/CoFe2O4 polymeric film of low loss dielectric constant, high magnetic properties, and perceptible terahertz shielding effectiveness. Pure cobalt ferrite magnetic nanoparticles (CoFe2O4 MNPs) were prepared by a facile‐modified solution deposition method. Then, the nanoparticles were loaded to poly (methyl methacrylate) of different ratios (x = 0, 5, 10, 15, and 20 wt%) to synthesize films by evaporative casting technique. X‐ray diffraction (XRD) evidenced the formation of CoFe2O4 MNPs in the cubic spinal structure. The FTIR confirmed the interaction of CoFe2O4 MNPs with PMMA chains. Compared to the pure PMMA, the PMMA/CoFe2O4 nanocomposites were more thermally stable, as evidenced by thermogravimetric analysis, (TGA) and differential scanning calorimetry (DSC). The micrograph images by FESEM unraveled that CoFe2O4 MNPs have formed in different geometrical shapes (nanocubes, nanotubes, and nano oval). The values of the band gap energy were computed by the absorption spectra fitting (ASF) method. It varied from 4.94 to 4.68 eV, as the CoFe2O4 MNPs contents were changed from 0 to 20 wt%. Compared to host PMMA, the dielectric permittivity was enhanced, while the dielectric loss was slightly decreased. Therefore, the prepared film can be employed as a passive component in electronic circuits, namely capacitors and supercapacitors. The shielding effectiveness (SE) was found to be improved with frequency and CoFe2O4 content, reflecting the applicability of PMMA/CoFe2O4 MNPs films in terahertz shielding. The magnetic parameters were investigated by a vibrating sample magnetometer (VSM) and were found to increase with CoFe2O4 content, which could be used as a flexible film in magnetic applications.
Polymyxin B/chlorine e6 conjugated hyaluronate dot particles for antimicrobial photodynamic therapy
Authors: Kim Yoonyoung , Oh Kyung Taek , Youn Yu Seok , Lee Eun Seong
Published: January 2023

In this study, we report ultrafine‐sized antibiotic dot particles targeting gram‐negative bacteria. The water‐soluble ultrafine‐sized hyaluronate dot (dHA) was conjugated with polymyxin B (PMB, as a target material for lipopolysaccharide on a gram‐negative bacteria) and chlorine e6 (Ce6, as a model photosensitizer), and it was denoted as dHA‐(PMB/Ce6). These dot particles interacted with lipopolysaccharide (LPS) on gram‐negative bacteria, which enabled PMB‐mediated docking to the outer membrane of gram‐negative cells. In the antimicrobial experiments using Escherichia coli cells, the phototoxic singlet oxygen generated from the dHA‐(PMB/Ce6) under light irradiation inhibited E. coli cell growth. This demonstrated that dHA‐(PMB/Ce6) can provide light‐activated selective phototoxicity against gram‐negative bacteria. We expect that the dot particle system can be used as an efficient method for improved antimicrobial treatment.
The adhesive energies between Poly(3‐hexylthiophene) and Polyvinylpyrrolidone for organic electronic devices: Hybrid‐exchange density‐functional‐theory studies
Authors: Du Xiaoyu , Wu Wei , Choy Kwang‐Leong
Published: January 2023

Studying the building blocks for organic electronics—molecules—is important for achieving a great performance for organic electronic devices. Poly(3‐hexylthiophene) (P3HT) and povidone (PVP) are common molecules chosen for the semiconducting and dielectric layers of organic electronic devices, respectively. Here, we have applied the hybrid‐exchange density‐functional theory, taking into account empirical dispersion forces and basis set superposition errors, to study the adhesive energies and optimal geometries when integrating the two types of molecules. To ease the analysis of the molecular structures, we have simplified the polymer chain structure to the monomer, dimer and trimer for the P3HT and PVP. By using B3LYP and BLYP functionals in combination with dispersion forces, we have found that the optimal inter‐molecular vertical distances between P3HT and PVP are approximately 3.6, 6 and 5 Å for monomer, dimer and trimer, respectively, with the lowest adsorption energy of ~−0.35, −0.15 and −0.45 eV. However, the sliding effect for the molecular combination is relatively small. These computational results can be potentially compared with the relevant experiments on the molecular crystal structure. The molecular orbitals of the P3HT and PVP molecules show that the charge density is mainly on the five‐member rings rather than the polymer chains, which further supports our finite‐chain approximation. Our calculations, especially the potential curves, could be useful for the optimal design of molecular structures for organic electronic devices.
Surgical ligation, not transcatheter closure, associated with a higher severity of bronchopulmonary dysplasia in extremely preterm infant intervened for patent ductus arteriosus
Authors: Wei Yu‐Jen , Ju Ying‐Tzu , Hsieh Min‐Ling , Kan Chung‐Dann , Lin Yung‐Chieh , Wang Jieh‐Neng
Published: January 2023

Objective

Patent ductus arteriosus (PDA) is a common complication among premature infants, which may be responsible for prematurity‐related complications such as bronchopulmonary dysplasia (BPD). It is unclear whether different interventional methods contribute to the severity of BPD, given the original National Institute of Child Health and Human Development (NICHD) 2001 definition. To date, surgical ligation and the transcatheter approach have been equally successful in premature infants with hemodynamically significant PDA after medical treatment failure. Immediate improvement in the respiratory condition has been reported after transcatheter closure. However, the short‐term pulmonary outcome has not been clarified yet.

Methods

This retrospective study investigated infants born with a body weight <1000 g and who underwent either surgical ligation or transcatheter closure of PDA in a single tertiary institution. The infants were divided into groups according to the type of procedure (surgical ligation or transcatheter occlusion). The primary outcome was the severity of BPD at discharge or at a postmenstrual age of 36 weeks. The outcome was analyzed with logistic regression.

Results

Forty‐four patients met the inclusion criteria, of whom 14 underwent transcatheter occlusion and 30 underwent surgical ligation. The overall birth body weights and gestational age ranges were not different. The univariate model revealed an association between the procedure type and BPD severity. After adjusting for confounders, the multivariate model confirmed associations between BPD severity and procedure type and severe respiratory distress syndrome requiring surfactant.

Conclusion

Compared with the transcatheter approach, surgery for PDA in extremely preterm infants is associated with severe BPD at discharge. Further large‐scale studies are needed to determine the exact mechanism.
Effect of lockdowns on the epidemiology of pediatric respiratory disease—A retrospective analysis of the 2021 summer epidemic
Authors: Kruizinga Matthijs D. , Noordzij Jeroen G. , van Houten Marlies A. , Wieringa Jantien , Tramper‐Stranders Gerdien A. , Hira Vishal , Bekhof Jolita , Vet Nienke J. , Driessen Gertjan J. A. , van Veen Mirjam
Published: January 2023

Background

The imposition of lockdowns during the severe acute respiratory syndrome coronavirus‐2 pandemic led to a significant decrease in pediatric care utilization in 2020. After restrictions were loosened, a surge in pediatric respiratory disease was observed in pediatric wards. The aim of this study was to quantify the effect of the lockdown(s) on the incidence of pediatric respiratory disease.

Methods

For this multicenter retrospective study, emergency department (ED) visit and admission data between January 2017 and September 2021 was collected from eight general hospitals in the Netherlands. Clinical diagnoses were extracted and categorized in groups (“communicable infectious disease,” “all respiratory infections,” “upper respiratory tract infection,” “lower respiratory tract infection,” and “asthma/preschool wheezing”). The incidence of admissions and ED visits during 2020 and 2021 was compared to the incidence in 2017–2019.

Results

Successive lockdowns resulted in a maximum decrease of 61% and 57% in ED visits and admissions, respectively. After loosening restrictions during the summer of 2021, a 48% overall increase in ED visits and 31% overall increase in admission numbers was observed in July compared to the average July in 2017–2019. This was explained by a 381% increase in ED visits and a 528% increase in ward admissions due to overall respiratory infections, mainly due to lower respiratory tract infections.

Conclusions

Successive lockdowns in the spring and winter of 2020 and 2021 led to a decreased incidence of communicable infections, especially respiratory tract infections. The resulting lack of pediatric immunity resulted in an off‐season surge in care utilization at an unexpected moment.
Exclusion of Mediterranean ant species enhances biological control of the invasive mealybug Delottococcus aberiae in citrus
Authors: Plata Ángel , Gómez‐Martínez María A. , Beitia Francisco J. , Tena Alejandro
Published: January 2023

BACKGROUND

Delottococcus aberiae is an invasive mealybug that produces severe damage in Spanish citrus. This mealybug has established a mutualistic relationship with native Mediterranean ant species that may limit biological control of this pest. Herein, we evaluated the effect of tending ants on the biological control of D. aberiae. To do this, we compared: (i) the density of D. aberiae, (ii) the density of its natural enemies, and (iii) the damage produced by the mealybug in trees with (control) and without ants (ants excluded with sticky barriers) in two citrus orchards across two consecutive years.

RESULTS

Lasius grandis was the most abundant ant species in both orchards and represented more than 95% of the ants tending D. aberiae in control trees. Spiders and lacewings were the most abundant predators observed in mealybug colonies, and the exclusion of mutualistic ants increased their abundance. Moreover, in control trees, ant activity throughout the year was negatively correlated with the relative abundance of predators (number of predators per mealybug). No parasitoids were recovered during field experiments. Ant exclusion reduced the density of D. aberiae and the ratio of damaged fruit at harvest across years and orchards.

CONCLUSIONS

This work corroborates the previous finding that D. aberiae benefits from its mutualistic relationship with L. grandis, probably because the presence of ants reduced the abundance of generalist predators. This mutualism can be disrupted using physical barriers on on the trunk. Further research should assess other methods of ant control that are more economic and feasible for citrus producers. © 2023 Society of Chemical Industry.
Experimental Identification of Atomic Orbital Contributions to SnS Valence Band using Polarization‐Dependent Angle‐Resolved Photoemission Spectroscopy
Authors: Suzuki Issei , Kawanishi Sakiko , Tanaka Kiyohisa , Omata Takahisa , Tanaka Shin-ichiro
Published: January 2023

Angle‐resolved photoemission spectroscopy (ARPES) is performed on single‐crystalline tin(II) sulfide (SnS) over a wide energy range (from Fermi level to −10 eV) using four measurement geometries with different excitation light polarizations and sample rotation angles. Based on the different symmetries of the atomic orbitals with respect to the mirror plane, the contribution of each atomic orbital of the constituent elements to the SnS valence band is determined. The results obtained agree with those of first‐principles calculations. Experimental results indicate that at the top of the valence band, the S 3py and 3pz contributions are strong near the Z and Γ points, respectively. Meanwhile, in the same region, the S 3px contribution is minimal and is concentrated at −2 eV lower than that of the valence band maximum. Although ARPES measurements are performed at different geometries, direct comparisons of the obtained measurements with calculation results are rarely conducted over such a wide energy range. This study is an effective example of experimental identification of the electronic band structures.
The battle for trans rights: Political spectacle theory and its implications for education policy
Authors: Castillo Sherri
Published: January 2023

In the United States, an increasing political divide and an emphasis on culture war issues have increased legislation and policy targeting transgender and non‐binary students in public education systems. Transgender and non‐binary identities are weaponized by conservative politicians who seek to influence policies in schools. Local, state, and federal protections are the solution to end discriminatory policies and the weaponization of transgender and non‐binary identities for political gain.
Nanostructured MoS2 with Interlayer Controllably Regulated by Ionic Liquids/Cellulose for High‐Capacity and Durable Sodium Storage Properties
Authors: Tao Wenjie , Chen Jianqiang , Xu Chengjie , Liu Shuai , Fakudze Sandile , Wang Jie , Wang Chen
Published: January 2023

Low intrinsic conductivity and structural instability of MoS2 as an anode of sodium‐ion batteries limit the liberation of its theoretical capacity. Herein, density functional theory simulations for the first time optimize MoS2 interlayer distance between 0.80 and 1.01 nm for sodium storage. 1‐Butyl‐3‐methyl‐imidazolium acetate ([BMIm]Ac) induces cellulose oligomers to intercalate MoS2 interlayers for achieving controllable distance by changing the mass ratio of cellulose to [BMIm]Ac. Based on these findings, porous carbon loading the interlayer‐expanded MoS2 allowing Na+ to insert with fast kinetics is synthesized. A carbon layer derived from [BMIm]Ac and cellulose coating the composite prevents the MoS2 from contacting electrolytes, leading to less sulfur loss for a more reversible specific capacity. Meanwhile, MoS2 and carbon have a strong interfacial connection through MoN binding, contributing to enhanced structural stability. As expected, while cycling 250 times at 0.1 A g‐1, the MoS2‐porous carbon composite displays an optimal reversible capacity at 517.79 mAh g‐1 as a sodium‐ion batteries anode. The cyclic test of 1.0 A g‐1 also shows considerable stability (310.74 mAh g‐1 after 1000 cycles with 86.26% retentive capacity). This study will open up new possibilities of modifying MoS2 that serves as an applicable material as sodium‐ion battery anode.
Stable and Ordered Body‐Centered Cubic PdCu Phase for Highly Selective Hydrogenation
Authors: Li Peicai , Liu Xia , Guo Mingrui , Pi Yecan , Wang Ning , Bai Shuxing , Xu Yong , Sun Qi
Published: January 2023

Phase engineering of nanomaterials plays a crucial role for regulating the catalytic performance. Nevertheless, great challenges still remain for elucidating the structure–selectivity correlation. Herein, this study demonstrates that the body‐centered cubic phase of PdCu (bcc‐PdCu) can serve as a highly active and selective catalyst for 3‐nitrostyrene (NS) hydrogenation under mild conditions. In particular, bcc‐PdCu displays a 3‐nitro‐ethylbenzene (NE) selectivity of 93.8% with a turnover frequency (TOF) value of 4573 h−1 at 30 °C in the presence of H2. With the assistance of NH3∙BH3, the selectivity of 3‐amino‐styrene (AS) reaches 94.5% with a TOF value of 13 719 h−1. Detailed experimental and theoretical calculations reveal that improved NE selectivity is ascribed to the selective adsorption of the CC bond and desorption of NE on bcc‐PdCu. Moreover, the presence of NH3∙BH3 facilitates the selective hydrogenation of NO2 due to their strong interaction and thus leads to the formation of AS. This work provides an efficient selective catalyst for NS hydrogenation under mild conditions, which may attract immediate interests in the fields of materials, chemistry, and catalysis.
Metaheuristic‐based machine learning modeling of the compressive strength of concrete containing waste glass
Authors: Ben Seghier Mohamed El Amine , Golafshani Emadaldin Mohammadi , Jafari‐Asl Jafar , Arashpour Mehrdad
Published: January 2023

Waste glass (WG) can be used as fine aggregate and powder in concrete mixtures, preventing pollution induced by this non‐biodegradable material. The properties of WG‐included concrete should be examined before its practical use. Compressive strength (CS) is one of the most crucial characteristics of concrete, and the measurement of which needs time‐consuming and expensive experiments. The use of machine learning (ML) methods for modeling the CS of concrete can help achieve more reliable and precise models. In this study, a comprehensive database of WG‐included concrete was collected from the literature. Next, four ML methods, including support vector regression (SVR), least‐square support vector regression (LSSVR), adaptive neuro‐fuzzy inference system (ANFIS), and multilayer perceptron neural network (MLP) were served in the CS modeling. A recently proposed metaheuristic method, called marine predators algorithm (MPA), was proposed to optimize the control parameters of the ML models to guarantee generalized accuracy. Results indicate that the hybrid LSSVR‐MPA model outperforms the other developed ML models comparing the error metrics with an RMSE = 2.447 MPa and R2 = 0.983. The sensitivity analysis reveals that replacing the cement with WG powder decreases the CS, whereas serving the WG as the replacement for natural fine aggregate improves the CS.
Optimal parameters for tall buildings with a single viscously damped outrigger considering earthquake and wind loads
Authors: Malik Faisal Nissar , Kolay Chinmoy
Published: January 2023

Tall buildings suffer from low inherent damping and high flexibility. Therefore, a core‐outrigger system is often used to stiffen such buildings. A modified form, known as the damped outrigger system, wherein vertically oriented dampers are installed between outriggers and perimeter columns, has been recently developed to supplement the damping. This paper studies the efficacy of a viscously damped outrigger system through dynamic analysis of a 60‐story tall building subjected to nonconcurrent earthquake and wind excitations. Two ground motion sets (100 accelerograms) are used for the former and wind tunnel test data for the latter. Effects of three building parameters, namely, (i) the core‐to‐column stiffness ratio, (ii) the outrigger location, and (iii) the damper size, on the dynamic characteristics and seismic and wind responses are evaluated. Effects of damper nonlinearity on seismic and wind responses are also investigated considering energy‐equivalent nonlinear viscous dampers. Finally, the optimum values of these parameters are determined. For example, the optimum outrigger location is found to be between
to
, where
is the height of the building. The results also show that the damped outrigger system significantly outperforms the conventional one for seismic excitation, and it is very effective in reducing the wind‐induced floor accelerations, provided the parameters are chosen appropriately.
Sketching Out the Contours
Authors: Agostino Ana , Elmhirst Rebecca , Gómez Marlene , Harcourt Wendy , Kotsila Panagiota
Published: January 2023

In this chapter, we set out the book’s engagements with feminist political ecology (FPE) theory and practice. We first position the book in relation to FPE discussions underlying how the field is evolving as an open-ended set of discourses responding to the different crises and disruptions caused by the last years of environmental, climate, health, economic and political crises. We then briefly explain how the book was shaped through four years of the relationships and knowledge co-production within the Wellbeing, Ecology, Gender and Community Innovative Training Network (WEGO-ITN), followed by a discussion on the main themes emerging in the book chapters and a finishing with a section indicating where the contributors of the book are heading next. The book is rooted in the networks and journeys between activism, academia and policy arenas reflecting on the many situated conversations and stories within FPE.
Untold Climate Stories: Feminist Political Ecology Perspectives on Extractivism, Climate Colonialism and Community Alternatives
Authors: Ekowati Dian , Maimunah Siti , Owen Alice , Wangari Muneri Eunice , Elmhirst Rebecca
Published: January 2023

In this chapter, we explore what is learned when our reflections on the systemic injustices that underpin climate change are woven together through feminist political ecology, with its emphasis on situated knowledges, lived experience and the everyday. Drawing on our research and activism in Kenya, Indonesia and the United Kingdom, we exchange reflections relating to extractivism and its logic of endless growth, corporate enclosure of land and water, erosion of biodiversity and the exploitation of life, enabled through coloniality. Extractivist depletion is what creates myriad forms of climate injustice. Bringing together stories from diverse contexts including communities impacted by mining and oil palm in Indonesia, oil drilling in the United Kingdom and pastoralists in Kenya, we show that while extractivism alters relationships with the land in extraordinarily harmful ways, mainstream climate stories obscure these realities and continue to decentre any sense of root causes. We share our reflections on the consequences that follow, but also show how shining a light on extractivism can reveal the persistence of healthier, reciprocal and replenishing relations with the land, water and creatures.
Ageing and Feminist Political Ecology
Authors: Dupuis Constance , Nakamura Nanako
Published: January 2023

In this chapter, we explore how applying a feminist political ecology (FPE) lens to ageing shows how ageing experiences are relational and dynamic processes of embodying everyday practices and ethics of care. We apply writings on post-capitalist community economies and rupturist gerontology and FPE intersectional thinking and link them to two studies of ageing in Japan and Uruguay. We analyse ageing as part of dynamic socionatural relations and the ethics of care including the agentic roles played by miso, machines, fungus, climate, and politics. Our chapter shows how the role played by socionatural relations in ageing experiences demands more careful attention.
Evidenzbasiertes Wildtiermanagement
Authors: Voigt Christian C.
Published: January 2023

Wildtiere sind in einer durch den Menschen intensiv genutzten Landschaft vielen anthropogenen Faktoren ausgesetzt, die nicht nur Einfluss auf ihre Bewegungen, sondern auch direkt Einfluss auf ihre Gesundheit und ihr Überleben haben. Manche Arten nutzen die anthropogenen Landschaften zu ihrem Vorteil und breiten sich aus, andere verlieren ihre Lebensräume. In diesem Buch werden die wissenschaftlichen Evidenzen zum Management ausgewählter Wildtierarten zusammengetragen. Ein evidenzbasiertes Management ist kritisch, um die Konflikte zwischen Menschen und Wildtieren zu reduzieren oder im besten Fall zu lösen. Diesem Ansatz folgend ist das Buch sowohl für die Wissenschaft als auch für die Praxis gedacht.

Wild animals are exposed to many anthropogenic factors in a landscape intensively used by humans, which not only influence their movements but also directly affect their health and survival. Some species use anthropogenic landscapes to their advantage and flourish, others lose their habitats. This book brings together the scientific evidence on the management of selected wildlife species. Evidence-based management is critical to reduce or, in the best case, resolve human-wildlife conflicts. Following this approach, this book is intended for both academics and practitioners.
Das Management des Fuchses sollte auf wissenschaftlichen Grundlagen anstatt auf Annahmen basieren
Authors: Kistler Claudia , Gloor Sandra , Hegglin Daniel , Bontadina Fabio
Published: January 2023

Der Rotfuchs Vulpes vulpes wird in Europa intensiv bejagt. Als Begründung für die Jagd wird aufgeführt, dass Füchse gefährdete Tierarten sowie Nutztiere erbeuten, Krankheiten auf den Menschen und auf Haustiere übertragen und für Konflikte mit den Menschen im Siedlungsraum sorgen. Allerdings gibt es zunehmend Belege, dass die vorherrschenden Methoden der Fuchsjagd, trotz grossem Aufwand durch die Jägerschaft, weder die Bestände noch die verursachten Schäden wirksam und nachhaltig reduzieren. Die Jagd auf Füchse basiert aktuell nicht auf wissenschaftlichen Grundlagen, denn es fehlen Bestandszahlen sowie klar definierte und messbare Ziele. Hinzu kommt, dass nicht evaluiert wird, wie sich die jagdlichen Eingriffe auf die Fuchsbestände auswirken. Zudem werfen verschiedene Jagdmethoden wie die Baujagd mit Hunden oder der Einsatz von Schrot grundsätzliche ethische und tierschützerische Fragen auf. Daher ist ein neues Managementkonzept für den Fuchs gefordert, das ökologische, ökonomische und ethische Kriterien beinhaltet und neben Abschüssen auch nicht-letale Massnahmen einbezieht. Dies unter anderem auch, weil die wachsenden Fuchsbestände im Siedlungsraum angepasste Lösungen erfordern. Im vorliegenden Kapitel zeigen wir auf, welche Grundlagen für ein evidenzbasiertes Fuchsmanagement notwendig sind.

Summary

The red fox Vulpes vulpes is intensively hunted in Europe. The reason given for the hunting are that foxes prey on endangered species and livestock, transmit zoonoses, transmit diseases to domestic animals, and cause conflicts with humans in urban areas. However, there is increasing evidence that the prevailing hunting methods are unlikely to effectively and sustainably reduce either populations or the damage caused, despite the large investment of time by hunters. The hunting of foxes is generally not based on scientific principles, there is a lack of population figures, clearly defined and measurable objectives, and there is no evaluation how hunting interventions impact fox populations. Furthermore, various hunting methods, such as den hunting with dogs or the use of shotgun pellets, raise profound ethical and animal welfare questions. Therefore, a new management concept for the red fox is required that takes ecological, economic and ethical criteria into account and includes non-lethal measures in addition to culling. Moreover, the growing urban fox populations require adapted solutions. In this chapter, we outline which basics are necessary for an evidence-based fox management.
Der Nordamerikanische Waschbär in Deutschland – Hintergrund, Konfliktfelder & Managementmaßnahmen
Authors: Michler Berit Annika , Dati Francesco , Michler Frank-Uwe
Published: January 2023

Der Nordamerikanische Waschbär gehört zu den gebietsfremden Vertretern der deutschen Raubsäugerfauna und ist eine der am stärksten omnivor ausgerichteten Säugetierarten weltweit. Der seit Ende der 1930er-Jahre in Deutschland angesiedelte Kleinbär wird in den letzten Jahren vermehrt als Gefahr für einheimische Tierarten sowie als potenzieller Krankheitsüberträger wahrgenommen. Aufgrund seiner anpassungsfähigen, urbanophilen Lebensweise nehmen auch Mensch-Waschbär-Interaktionen und damit verbundene Problemfelder im Siedlungsraum zu. Der Artikel fasst den aktuellen Kenntnisstand zu den Auswirkungen der Waschbärenbesiedlung in Deutschland zusammen, gibt einen Überblick zum rechtlichen Status des Neubürgers und stellt konkrete Managementmaßnahmen und Handlungsempfehlungen als Resultat von Freilandforschung und Praxiserfahrung vor, mit denen die wesentlichen Konfliktfelder nachhaltig und effektiv minimiert werden können.

Summary

The North American raccoon is an introduced carnivore species in Germany and one of the most omnivorous mammal species worldwide. Established in Germany since the end of the 1930s, the procyonid has become increasingly perceived as a threat to native species as well as a potential vector of disease in recent years. Due to its adaptable, urbanophilic lifestyle, human-raccoon interactions and associated problems in settlement areas are also increasing. The article summarises the current state of knowledge on the impacts of raccoon settlement in Germany and provides an overview of the legal status of the newcomer. Concrete management measures and recommendations for action are presented as a result of field research and practical experience. In this way, the areas of conflict caused by the raccoon presence can be minimised sustainably and effectively.
Spread complexity and topological transitions in the Kitaev chain
Authors: Caputa Pawel , Gupta Nitin , Haque S. Shajidul , Liu Sinong , Murugan Jeff , Van Zyl Hendrik J. R.
Published: January 2023

Abstract

A number of recent works have argued that quantum complexity, a well-known concept in computer science that has re-emerged recently in the context of the physics of black holes, may be used as an efficient probe of novel phenomena such as quantum chaos and even quantum phase transitions. In this article, we provide further support for the latter, using a 1-dimensional p-wave superconductor — the Kitaev chain — as a prototype of a system displaying a topological phase transition. The Hamiltonian of the Kitaev chain manifests two gapped phases of matter with fermion parity symmetry; a trivial strongly-coupled phase and a topologically non-trivial, weakly-coupled phase with Majorana zero-modes. We show that Krylov-complexity (or, more precisely, the associated spread-complexity) is able to distinguish between the two and provides a diagnostic of the quantum critical point that separates them. We also comment on some possible ambiguity in the existing literature on the sensitivity of different measures of complexity to topological phase transitions.
Holographic QFTs on AdSd, wormholes and holographic interfaces
Authors: Ghodsi A. , Ghosh J. K. , Kiritsis E. , Nitti F. , Nourry V.
Published: January 2023

Abstract

We consider three related topics: (a) Holographic quantum field theories on AdS spaces. (b) Holographic interfaces of flat space QFTs. (c) Wormholes connecting generically different QFTs. We investigate in a concrete example how the related classical solutions explore the space of QFTs and we construct the general solutions that interpolate between the same or different CFTs with arbitrary couplings. The solution space contains many exotic flow solutions that realize unusual asymptotics, as boundaries of different regions in the space of solutions. We find phenomena like “walking” flows and the generation of extra boundaries via flow fragmentation.
On the stability of scale-invariant black holes
Authors: Boudet S. , Rinaldi M. , Silveravalle S.
Published: January 2023

Abstract

Quadratic scale-invariant gravity non minimally coupled to a scalar field provides a competitive model for inflation, characterized by the transition from an unstable to a stable fixed point, both characterized by constant scalar field configurations. We provide a complementary analysis of the same model in the static, spherically symmetric setting, obtaining two Schwarzschild-de Sitter solutions, which corresponds to the two fixed points existing in the cosmological scenario. The stability of such solutions is thoroughly investigated from two different perspectives. First, we study the system at the classical level by the analysis of linear perturbations. In particular, we provide both analytical and numerical results for the late-time behavior of the perturbations, proving the stable and unstable character of the two solutions. Then we perform a semi-classical, non-linear analysis based on the Euclidean path integral formulation. By studying the difference between the Euclidean on-shell actions evaluated on both solutions, we prove that the unstable one has a meta-stable character and is spontaneously decaying into the stable fixed point which is always favoured.
On the saturation of late-time growth of complexity in supersymmetric JT gravity
Authors: Alishahiha Mohsen , Banerjee Souvik
Published: January 2023

Abstract

In this work we use the modified replica trick, proposed in arXiv:2205.01150, to compute the late time behaviour of complexity for JT gravity with 𝒩 = 1 and 𝒩 = 2 supersymmetries. For the 𝒩 = 1 theory, we compute the late time behaviour of complexity defined by the “quenched geodesic length” and obtain the expected saturation of complexity at time $$ t\sim {e}^{S_0} $$
t
~

e

S
0

, to a constant value with time-independent variance. For the 𝒩 = 2 theory, we explicitly compute complexity at the disk level which yields the late-time linear growth of complexity. However, we comment on the expectation of the late-time saturation by speculating the trumpet partition function and the non-perturbative corrections to the spectral correlation, relevant for the late time behaviour of complexity. Furthermore, we compute the matter correlation functions for both the theories.
Comments on the entanglement spectrum of de Sitter space
Authors: Banks Tom , Draper Patrick
Published: January 2023

Abstract

We argue that the Schwarzschild-de Sitter black hole entropy formula does not imply that the entanglement spectrum of the vacuum density matrix of de Sitter space is flat. Specifically, we show that the expectation value of a random projection operator of dimension d ≫ 1, on a Hilbert space of dimension D ≫ d and in a density matrix ρ = e–K with strictly positive spectrum, is $$ \frac{d}{D}\left(1+o\left(\frac{1}{\sqrt{d}}\right)\right) $$

d
D

1
+
o

1

d

, independent of the spectrum of the density matrix. In addition, for a suitable class of spectra the asymptotic estimates Tr (ρK) ~ ln D – o(1) and Tr [ρ(K – 〈K〉)2] = a〈K〉 are compatible for any order one constant a. We discuss a simple family of matrix models and projections that can replicate such modular Hamiltonians and the SdS entropy formula.
Binary collisions of dark matter blobs
Authors: Diamond Melissa D. , Kaplan David E. , Rajendran Surjeet
Published: January 2023

Abstract

We describe the model-independent mechanism by which dark matter and dark matter structures heavier than ~ 8 × 1011 GeV form binary pairs in the early Universe that spin down and merge both in the present and throughout the Universe’s history, producing potentially observable signals. Sufficiently dense dark objects will dominantly collide through binary mergers instead of random collisions. We detail how one would estimate the merger rate accounting for finite size effects, multibody interactions, and friction with the thermal bath. We predict how mergers of dark dense objects could be detected through gravitational and electromagnetic signals, noting that such mergers could be a unique source of high frequency gravitational waves. We rule out objects whose presence would contradict observations of the CMB and diffuse gamma-rays.
On Some Singular Limits Arising in Fluid Dynamic Modelling
Authors: Donatelli Donatella
Published: January 2023

Fluid dynamic equations are used to model various phenomena arising from physics, engineering, astrophysics, geophysics. One feature is that they take place at different time and length scales and it is important to understand which phenomena occur according to the use of single scales or to the interactions of them. From a mathematical point of view, these various physical behaviours give rise to different singular limits and, consequently to a different analysis of the asymptotic state of the governing equations. In this paper we will analyse a very simplified model given by a linearised continuity equation and by the classical momentum equation which include terms that take into account of rotation and we will show, according to the values of different scales, that the asymptotic behaviour of the model will be those of an incompressible fluid or of a geostrophic flow. Finally we point out, that the set of equations analysed in the paper may also fit in the artificial compressibility approximation methods.
Laser welding of tailored blanks made of Al-Si-coated 22MnB5 steel using a filler wire and a variable energy distribution laser optics
Authors: Coviello Donato , von der Heydt Jana , Rullo Lorenzo , Keßler Michael , De Vito Mariarosaria , D’Angola Antonio , Sorgente Donato
Published: January 2023

Laser welding of Al-Si-coated steels for hot stamping in automotive applications is problematic due to the mixing of the coating layers inside the molten pool that weakens the resulting weld seam. In this case, the most common welding procedure to overcome this issue consists in removing the Al-Si layer through laser ablation prior to the joining. This method continues to be the most widely used by major producers of tailor welded blanks, although in situ ablation of the Al-Si coating can be costly and time consuming. In this work, a novel approach consisting in joining as-received (i.e., not decoated) materials using a filler wire and an innovative variable energy distribution laser optics is introduced and tested on tailor welded blanks made of 22MnB5. Tensile tests of specimens obtained from a 33 full factorial design of experiment have shown an average value of ultimate tensile strength of 1523 MPa, which is much higher than the one usually observed in as-received welded then hot-stamped conditions and aligned with hot-stamped base material values. Hardness test results (494–543 HV0.5) were in the typical hot-stamped base material range of values as well, while SEM–EDS analyses detected no ferrite inclusions inside the fusion zone. Variations of the main process parameters have been considered on an iso-thickness and iso-material configuration, empirically demonstrating the stability and reliability of the proposed methodology as well as its suitability for production purposes.
Multiplicity and concentration of solutions to fractional anisotropic Schrödinger equations with exponential growth
Authors: Nguyen Thin Van , Rădulescu Vicenţiu D.
Published: January 2023

In this paper, we consider the Schrödinger equation involving the fractional $$(p,p_1,\dots ,p_m)$$

(
p
,

p
1

,
⋯
,

p
m

)

-Laplacian as follows $$\begin{aligned} (-\Delta )_{p}^{s}u+\sum _{i=1}^{m}(-\Delta )_{p_i}^{s}u+V(\varepsilon x)(|u|^{(N-2s)/2s}u+\sum _{i=1}^{m}|u|^{p_i-2}u)=f(u)\;\text{ in }\; {\mathbb {R}}^{N}, \end{aligned}$$

(
-
Δ
)

p

s

u
+

∑

i
=
1

m

(
-
Δ
)

p
i

s

u
+

V

(
ε
x
)

(
|
u
|

(
N
-
2
s
)
/
2
s

u
+

∑

i
=
1

m

|
u
|

p
i

-
2

u
)
=
f

(
u
)

in

R

N

,

where $$\varepsilon $$
ε
is a positive parameter, $$N=ps, s\in (0,1), 2\le p<p_1< \dots< p_m<+\infty , m\ge 1$$

N
=
p
s
,
s
∈

(
0
,
1
)

,
2
≤
p
<

p
1

<
⋯
<

p
m

<
+
∞
,
m
≥
1

. The nonlinear function f has the exponential growth and potential function V is continuous function satisfying some suitable conditions. Using the penalization method and Ljusternik–Schnirelmann theory, we study the existence, multiplicity and concentration of nontrivial nonnegative solutions for small values of the parameter. In our best knowledge, it is the first time that the above problem is studied.
Non-intrusive, imaging-based method for shock wave characterization in bubbly gas–liquid fluids
Authors: Cornel Wouter A. , Westerweel Jerry , Poelma Christian
Published: January 2023

A novel experimental imaging-based method is presented for the non-intrusive determination of shock wave characteristics (i.e. shock wave speed and magnitude, and shock-induced liquid velocity) in a bubbly flow solely from gas bubble velocities. Shock wave speeds are estimated by the relative motion between gas bubbles at two locations by splitting the camera field-of-view using a mirror construction, increasing the dynamic spatial range of the measurement system. Although gas bubbles have in general poor tracing properties of the local fluid velocity, capturing the relative dynamics provides accurate estimates for the shock wave properties. This proposed imaging-based method does not require pressure transducers, the addition of tracer particles, or volumetric reconstruction of the gas bubbles. The shock wave magnitude and shock-induced liquid velocity are computed with a hydrodynamic model, which only requires non-intrusively measured variables as input. Two reference measurements, based on pressure transducers and the liquid velocity field by particle image velocimetry, show that the proposed method provides reliable estimates for the shock wave front speed and the shock-induced liquid velocity within the experimental range of 70 $$< U_\textrm{s}<$$

<

U
s

<

400 m/s.

Graphical abstract
DDCAL: Evenly Distributing Data into Low Variance Clusters Based on Iterative Feature Scaling
Authors: Lux Marian , Rinderle-Ma Stefanie
Published: January 2023

This work studies the problem of clustering one-dimensional data points such that they are evenly distributed over a given number of low variance clusters. One application is the visualization of data on choropleth maps or on business process models, but without over-emphasizing outliers. This enables the detection and differentiation of smaller clusters. The problem is tackled based on a heuristic algorithm called DDCAL (1d distribution cluster algorithm) that is based on iterative feature scaling which generates stable results of clusters. The effectiveness of the DDCAL algorithm is shown based on 5 artificial data sets with different distributions and 4 real-world data sets reflecting different use cases. Moreover, the results from DDCAL, by using these data sets, are compared to 11 existing clustering algorithms. The application of the DDCAL algorithm is illustrated through the visualization of pandemic and population data on choropleth maps as well as process mining results on process models.
Radial basis function interpolation of fields resulting from nonlinear simulations
Authors: de Gooijer Boukje M. , Havinga Jos , Geijselaers Hubert J. M. , van den Boogaard Anton H.
Published: January 2023

Three approaches for construction of a surrogate model of a result field consisting of multiple physical quantities are presented. The first approach uses direct interpolation of the result space on the input space. In the second and third approaches a Singular Value Decomposition is used to reduce the model size. In the reduced order surrogate models, the amplitudes corresponding to the different basis vectors are interpolated. A quality measure that takes into account different physical parts of the result field is defined. As the quality measure is very cheap to evaluate, it can be used to efficiently optimize hyperparameters of all surrogate models. Based on the quality measure, a criterion is proposed to choose the number of basis vectors for the reduced order models. The performance of the surrogate models resulting from the three different approaches is compared using the quality measure based on a validation set. It is found that the novel criterion can effectively be used to select the number of basis vectors. The choice of construction method significantly influences the quality of the surrogate model.
The Heart Failure Optimization Study (HF-OPT): rationale and design
Authors: Sanchez R. , Duncker D. , Colley B. , Doering M. , Gummadi S. , Perings C. , Robertson M. , Shroff G. , Veltmann C. ,   Heart Failure Optimization Study (HF-OPT) Investigators
Published: January 2023

Background

According to the current guidelines, implantable cardioverter-defibrillators (ICD) for primary prevention in patients with heart failure and reduced ejection fraction (HFrEF) should not be considered until optimal guideline-directed medical therapy (GDMT) has been achieved for a minimum of 3 months. Optimization of GDMT often needs time beyond 3 months after diagnosis. The aim of the Heart Failure Optimization Study (HF-OPT) is to evaluate the recovery of left ventricular function beyond 3 months after diagnosis of newly diagnosed HFrEF.

Methods

The HF-OPT multicenter study is comprised of two non-randomized phases (registry and study). During the first 90 days a wearable cardioverter-defibrillator (WCD) is prescribed and patients are enrolled in an observational pre-study registry. Registry subjects meeting inclusion criteria for the study portion at day 90 have ongoing left ventricular ejection fraction (LVEF) reassessment at 90, 180 and 360 days after the index hospital discharge, regardless of continued WCD use. Approximately 600 subjects will be enrolled in the study portion. Of those, one-third are anticipated to start the study phase at day 90 with reduced LVEF. The primary objective of this study is to observe the rate of recovery of LVEF > 35% between 90 and 180 days, while key secondary endpoints include mortality and WCD recorded arrhythmias and shocks.

Discussion

The HF-OPT study will provide important information on the rate of additional recovery of LVEF > 35%, between 90 and 180 days, in newly diagnosed HF with reduced LVEF patients being titrated with GDMT. The results of the study may impact indications for primary prophylactic ICD implantation.
Granular cell tumour of the pancreas: a case report and systematic review
Authors: Tree Kevin , Kotecha Krishna , Mehta Shreya , Fuchs Talia L. , Toon Christopher W. , Gill Anthony J. , Samra Jaswinder S. , Mittal Anubhav
Published: January 2023

Purpose

Granular cell tumours (GCTs) of the pancreas are mostly benign and exceptionally rare, with no unique identifying radiological features. Following a case discussion of a patient with GCT, a comprehensive review of available literature was conducted to identify the common diagnostic features associated with GCT.

Methods

Following a case report identified in our institution, a systematic review was conducted by two authors in accordance with Preferred Reporting Items for Systematic review and Meta-Analysis protocols (PRISMA) guidelines. Databases MEDLINE, EMBASE, Scopus, World of Science, and grey literature were searched on August 2021. Inclusion criteria were histopathology diagnosed granular cell tumour of the pancreas.

Results

A 37-year-old male presented with 1 month of abdominal pain and an MRI demonstrating a dilated main pancreatic duct, distal parenchymal atrophy, but no focal lesion. Repeat MRI at 6 months re-demonstrated similar findings and subsequent endoscopic ultrasound was suspicious for main duct IPMN. Following multidisciplinary team discussion, a spleen-preserving distal pancreatectomy was performed. Histopathology demonstrated granular cell tumour with cells diffusely positive for S100 and no malignant transformation.

11 case reports were identified in the literature with diagnosis confirmed on tissue histopathology based on positive immunohistochemical staining for S-100 protein. Eight patients presented with gastrointestinal symptoms with abdominal pain the main presenting complaint (50%). 10 patients underwent CT with portal venous contrast and all underwent endoscopic examination. Imaging findings were similar in five studies for EUS which demonstrated a hypoechoic lesion with homogenous appearance. On non-contrast CT GCT was iso-enhancing, and with portal venous contrast demonstrated hypo-enhancement that gradually enhanced on late phases. Pre-operative diagnosis of pancreatic carcinoma was described in six cases based on imaging and biopsy, resulting in progression to surgical resection. Nine patients were managed surgically and no complications identified on follow-up (6–52 months).

Conclusion

The currently proposed management pathway includes EUS with biopsy and CT, and surgical resection recommended due to malignancy risk. Improved sample collection with EUS-FNA and microscopic assessment utilising S-100 immunohistochemistry may improve pre-operative diagnosis. Limitations include rare numbers in reported literature and short follow-up not allowing an assessment of GCT’s natural history and malignancy risk. Additional cases would expand the current dataset of GCTs of the pancreas, so that surgical resection may be avoided in the future.