bluuebunny/crossref_metadata_2025 huggingface dataset:
Augmented reality–assisted craniofacial reconstruction in skull base lesions — an innovative technique for single-step resection and cranioplasty in neurosurgery
Authors: Steiert Christine , Behringer Simon Phillipp , Kraus Luisa Mona , Bissolo Marco , Demerath Theo , Beck Juergen , Grauvogel Juergen , Reinacher Peter Christoph
Published: April 2022

Defects of the cranial vault often require cosmetic reconstruction with patient-specific implants, particularly in cases of craniofacial involvement. However, fabrication takes time and is expensive; therefore, efforts must be made to develop more rapidly available and more cost-effective alternatives. The current study investigated the feasibility of an augmented reality (AR)–assisted single-step procedure for repairing bony defects involving the facial skeleton and the skull base. In an experimental setting, nine neurosurgeons fabricated AR-assisted and conventionally shaped (“freehand”) implants from polymethylmethacrylate (PMMA) on a skull model with a craniofacial bony defect. Deviations of the surface profile in comparison with the original model were quantified by means of volumetry, and the cosmetic results were evaluated using a multicomponent scoring system, each by two blinded neurosurgeons. Handling the AR equipment proved to be quite comfortable. The median volume deviating from the surface profile of the original model was low in the AR-assisted implants (6.40 cm3) and significantly reduced in comparison with the conventionally shaped implants (13.48 cm3). The cosmetic appearance of the AR-assisted implants was rated as very good (median 25.00 out of 30 points) and significantly improved in comparison with the conventionally shaped implants (median 14.75 out of 30 points). Our experiments showed outstanding results regarding the possibilities of AR-assisted procedures for single-step reconstruction of craniofacial defects. Although patient-specific implants still represent the gold standard in esthetic aspects, AR-assisted procedures hold high potential for an immediately and widely available, cost-effective alternative providing excellent cosmetic outcomes.
Structural damage burden and hypertrophic olivary degeneration in pediatric postoperative cerebellar mutism syndrome
Authors: Beez Thomas , Munoz-Bendix Christopher , Mijderwijk Hendrik-Jan , Remke Marc , Hänggi Daniel
Published: April 2022

Cerebellar mutism syndrome (CMS) occurs in one out of four children after posterior fossa tumor surgery, with open questions regarding risk factors, pathophysiology, and prevention strategies. Because of similarities between several cerebellar syndromes, a common pathophysiology with damage to the dentato-thalamo-cortical and dentato-rubro-olivary pathways has been proposed. Hypertrophic olivary degeneration (HOD) is an imaging correlate of cerebellar injury observed for instance in stroke patients. Aim of this study was to investigate whether the occurrence and severity of CMS correlates with the extent of damage to the relevant anatomical structures and whether HOD is a time-dependent postoperative neuroimaging correlate of CMS. We performed a retrospective single center study of CMS patients compared with matched non-CMS controls. CMS occurred in 10 children (13% of the overall cohort) with a median age of 8 years. Dentate nucleus (DN) injury significantly correlated with CMS, and superior cerebellar peduncle (SCP) injury was associated by tendency. HOD was observed as a dynamic neuroimaging phenomenon in the postoperative course and its presence significantly correlated with CMS and DN injury. Children who later developed HOD had an earlier onset and tended to have longer persistence of CMS. These findings can guide surgical measures to protect the DN and SCP during posterior fossa tumor resections and to avoid a high damage burden (i.e., bilateral damage). Development of intraoperative neuromonitoring of the cerebellar efferent pathways as well as improved preoperative risk stratification could help to establish a patient-specific strategy with optimal balance between degree of resection and functional integrity.
Investigating the spatial resolution of EMG and MMG based on a systemic multi-scale model
Authors: Klotz Thomas , Gizzi Leonardo , Röhrle Oliver
Published: April 2022

While electromyography (EMG) and magnetomyography (MMG) are both methods to measure the electrical activity of skeletal muscles, no systematic comparison between both signals exists. Within this work, we propose a novel in silico model for EMG and MMG and test the hypothesis that MMG surpasses EMG in terms of spatial selectivity, i.e. the ability to distinguish spatially shifted sources. The results show that MMG provides a slightly better spatial selectivity than EMG when recorded directly on the muscle surface. However, there is a remarkable difference in spatial selectivity for non-invasive surface measurements. The spatial selectivity of the MMG components aligned with the muscle fibres and normal to the body surface outperforms the spatial selectivity of surface EMG. Particularly, for the MMG’s normal-to-the-surface component the influence of subcutaneous fat is minimal. Further, for the first time, we analyse the contribution of different structural components, i.e. muscle fibres from different motor units and the extracellular space, to the measurable biomagnetic field. Notably, the simulations show that for the normal-to-the-surface MMG component, the contribution from volume currents in the extracellular space and in surrounding inactive tissues, is negligible. Further, our model predicts a surprisingly high contribution of the passive muscle fibres to the observable magnetic field.
Optimal coalition structures for probabilistically monotone partition function games
Authors: Fatima Shaheen , Wooldridge Michael
Published: April 2022

For cooperative games with externalities, the problem of optimally partitioning a set of players into disjoint exhaustive coalitions is called coalition structure generation, and is a fundamental computational problem in multi-agent systems. Coalition structure generation is, in general, computationally hard and a large body of work has therefore investigated the development of efficient solutions for this problem. However, the existing methods are mostly limited to deterministic environments. In this paper, we focus attention on uncertain environments. Specifically, we define probabilistically monotone partition function games, a subclass of the well-known partition function games in which we introduce uncertainty. We provide a constructive proof that an exact optimum can be found using a greedy approach, present an algorithm for finding an optimum, and analyze its time complexity.
Net carbon dioxide emissions from an eroding Atlantic blanket bog
Authors: Artz Rebekka R. E. , Coyle Mhairi , Donaldson-Selby Gillian , Morrison Ross
Published: April 2022

The net impact of greenhouse gas emissions from degraded peatland environments on national Inventories and subsequent mitigation of such emissions has only been seriously considered within the last decade. Data on greenhouse gas emissions from special cases of peatland degradation, such as eroding peatlands, are particularly scarce. Here, we report the first eddy covariance-based monitoring of carbon dioxide (CO2) emissions from an eroding Atlantic blanket bog. The CO2 budget across the period July 2018–November 2019 was 147 (± 9) g C m−2. For an annual budget that contained proportionally more of the extreme 2018 drought and heat wave, cumulative CO2 emissions were nearly double (191 g C m−2) of that of an annual period without drought (106 g C m−2), suggesting that direct CO2 emissions from eroded peatlands are at risk of increasing with projected changes in temperatures and precipitation due to global climate change. The results of this study are consistent with chamber-based and modelling studies that suggest degraded blanket bogs to be a net source of CO2 to the atmosphere, and provide baseline data against which to assess future peatland restoration efforts in this region.
Mental Health among African American and Latinx Men who have sex with men after the COVID-19 Lockdown in Los Angeles – Findings from the HOPE cohort
Authors: Wang Yan , Kinsler Janni , Cumberland William G. , Young Sean D.
Published: April 2022

This study aimed to examine the depression and anxiety among men of color (primarily African American and Latinx) who have sex with men after the lockdown due to the COVID-19 pandemic. Outcomes included 21-item Beck Depression Inventory (BDI), 7-item Generalized Anxiety Disorder (GAD), and a 10-item COVID-related anxiety measure using a modified H1N1-related anxiety question. Independent variables were food insecurity and belief in government efficiency. Data were analyzed by Regression models with random cluster effects. Food insecurity experiences were significantly associated with higher depression (p < 0.001), higher anxiety (p < 0.001), and higher pandemic-related anxiety (p < 0.001). Higher levels of belief in government efficiency were significantly associated with lower depression (p < 0.05), less anxiety (p < 0.05), and less pandemic-related anxiety (p-value < 0.001). These findings emphasize the importance of establishing trust between government and at-risk communities when issuing public health policies, especially during unforeseen circumstances, as well as to ensure basic human rights, such as food security.
Economic Precariousness and the Transition to Parenthood: A Dynamic and Multidimensional Approach
Authors: van Wijk Daniël C. , de Valk Helga A. G. , Liefbroer Aart C.
Published: April 2022

Economic precariousness has taken on a central role in explanations of the postponement of childbearing in developed societies. However, most studies conceptualize and operationalize precariousness as being static and one-dimensional, which provides only a partial perspective on the links between precariousness and fertility. In this paper, we study precariousness as a dynamic and multidimensional concept, distinguishing between past and current precariousness as well as between precariousness relating to income and to employment. Analyses are based on Dutch full-population register data. We select all inhabitants of the Netherlands who left education in 2006 and follow them until 2018. Event history analyses show that current and past income and employment precariousness all have independent negative effects on the first birth rate for men. Current and past employment precariousness and past income precariousness also reduce the first birth rate for women, but current income precariousness increases women’s probability of first conception. When precariousness is both persistent and multidimensional, it is associated with a threefold decrease in the monthly probability of conceiving a first child for men and almost a halving of the probability for women. Our analyses show the need for going beyond static and one-dimensional analyses in order to understand how economic precariousness may affect fertility behaviour.
University autonomy under democratic backsliding: a case study of a plagiarism investigation against Serbian Minister of Finance (2014–2019)
Authors: Tomic Slobodan , Radeljic Branislav
Published: April 2022

Scholars have documented a tendency of (semi-)authoritarian regimes to undermine university autonomy, mainly through organizational (de jure) changes. This paper presents a case study of a publicly triggered plagiarism investigation by the University of Belgrade into the doctoral thesis of the Serbian Minister of Finance, one of the key members of the increasingly authoritarian regime. The analysis finds a proceduralized and delayed response of the university’s leadership, which indicates lowered de facto autonomy from politics, despite the university’s continually high de jure autonomy. The investigation was closed only after a mobilization within the academic community which resulted in a university’s blockade that forced its leadership to retract the contentious thesis. The case study shows that, in contexts of democratic backsliding, political capture can extend farther than usually thought, impacting even the implementation of internal university standards. On the other hand, the analysis also shows that political capture is not necessarily irreversible and that academic community can mobilize to ‘undo’ it. This reinforces the notion of academic communities as value-driven groups capable of exerting peer pressure to override even authoritarian pressures. In order to understand the dynamic of the plagiarism inquiry in its entirety, we apply insights from theory of power to complement and overcome the limitations of the conventional theoretical frameworks on democratic backsliding and academic autonomy.
Co-Shaping an Ecosystem for Responsible AI: Five Types of Expectation Work in Response to a Technological Frame
Authors: Minkkinen Matti , Zimmer Markus Philipp , Mäntymäki Matti
Published: April 2022

Governing artificial intelligence (AI) requires cooperation, although the collaboration’s form remains unclear. Technological frames provide a theoretical perspective for understanding how actors interpret a technology and act upon its development, use, and governance. However, we know little about how actors shape technological frames. In this paper, we study the shaping of the technological frame of the European ecosystem for responsible AI (RAI). Through an analysis of EU documents, we identified four expectations that constitute the EU’s technological frame for the RAI ecosystem. Moreover, through interviews with RAI actors, we revealed five types of expectation work responding to this frame: reproducing, translating, and extending (congruent expectation work), and scrutinizing and rooting (incongruent expectation work). Furthermore, we conceptualize expectation work as actors’ purposive actions in creating and negotiating expectations. Our study contributes to the literature on technological frames, technology-centered ecosystems, and RAI while also elucidating the dimensions and co-shaping of technological frames.
Social position of older immigrants in the Netherlands: where do immigrants perceive themselves on the societal ladder?
Authors: Klokgieters Silvia S. , van Tilburg Theo G. , Deeg Dorly J. H. , Huisman Martijn
Published: April 2022

Older Turkish and Moroccan immigrants are often ascribed a low social position based on their relatively unfavourable educational level, occupational status and income. Yet immigrants emigrated to improve their social position and came from contexts where determinants of social position might be based on different socio-cultural circumstances than those used in the country of settlement. In order to understand immigrants’ own perception of their social position, we interviewed 23 60–68 year old immigrants from Turkish and Moroccan origin in the Netherlands. Using a ten rung ladder, participants were asked to position themselves in the societal hierarchy before migration, after settlement and currently. Most participants positioned themselves at a middle or high position on the societal ladder. Circumstances used for positioning were related to socioeconomic indicators, but also to social affirmation, family, social integration, physical, mental health, happiness and complying to religious prescriptions. When these circumstances were deemed favourable, participants tended to position themselves higher. Our findings also show that the circumstances that participants used for positioning themselves varied across the life course. These findings complement the picture of the often low objective low socioeconomic position of older immigrants and show that immigrants’ perception of their subjective social position reflects a broader set of circumstances than just socioeconomic ones.
Optical properties of lithium titanate as a potential layer in light harvesters
Authors: Gadelrab Olivia , Elmahgary Maryam G. , Mahran Abdelrahman M. , Ganoub Moustafa , Abdellatif Sameh O.
Published: April 2022

Various solar cell architectures and materials are currently studied, seeking enhanced photon management mechanisms. Herein, we provide an attempt to prepare, characterize, model, and simulate a novel semiconductor, Lithium Titanate, which has a band gap of 3.55 eV. The semiconductor was prepared from H2TiO3 and LiCO3 by calcination at 500 °C for 5 h after grinding with deionized water. XRD, SEM, EDX, and AFM carried out a complete morphological characterization on powder and thin-film levels. Additionally, experimentally validated atomistic DFT modeling was performed where the density of states and the imaginary part of the permittivity were extracted. Finally, the optical transmission spectrum was simulated for a 4.28 μm thickness film, with the aid of a finite-difference time-domain solver, against an experimentally measured spectrum, showing a root-mean-square mismatching error of 3.78%.
Travelling Waves for Adaptive Grid Discretizations of Reaction Diffusion Systems III: Nonlinear Theory
Authors: Hupkes H. J. , Van Vleck E. S.
Published: April 2022

In this paper we consider a spatial discretization scheme with an adaptive grid for the Nagumo PDE and establish the existence of travelling waves. In particular, we consider the time dependent spatial mesh adaptation method that aims to equidistribute the arclength of the solution under consideration. We assume that this equidistribution is strictly enforced, which leads to the non-local problem with infinite range interactions that we derived in Hupkes and Van Vleck (J Dyn Differ Eqn, 2021). Using the Fredholm theory developed in Hupkes and Van Vleck (J Dyn Differ Eqn, 2021) we setup a fixed point procedure that enables the travelling PDE waves to be lifted to our spatially discrete setting.
From Boltzmann Equation for Granular Gases to a Modified Navier–Stokes–Fourier System
Authors: Alonso Ricardo J. , Lods Bertrand , Tristani Isabelle
Published: April 2022

In this paper, we give an overview of the results established in Alonso (http://arxiv.org/org/abs/2008.05173, 2020) which provides the first rigorous derivation of hydrodynamic equations from the Boltzmann equation for inelastic hard spheres in 3D. In particular, we obtain a new system of hydrodynamic equations describing granular flows and prove existence of classical solutions to the aforementioned system. One of the main issue is to identify the correct relation between the restitution coefficient (which quantifies the rate of energy loss at the microscopic level) and the Knudsen number which allows us to obtain non trivial hydrodynamic behavior. In such a regime, we construct strong solutions to the inelastic Boltzmann equation, near thermal equilibrium whose role is played by the so-called homogeneous cooling state. We prove then the uniform exponential stability with respect to the Knudsen number of such solutions, using a spectral analysis of the linearized problem combined with technical a priori nonlinear estimates. Finally, we prove that such solutions converge, in a specific weak sense, towards some hydrodynamic limit that depends on time and space variables only through macroscopic quantities that satisfy a suitable modification of the incompressible Navier–Stokes–Fourier system.
Sorption of 60Co(II) from aqueous solutions onto biosynthesized zinc oxide nanocomposites
Authors: Mekawy Zakaria A. , Moussa Saber I. , Mousa Abeer M. , Dakroury Gehan A. , Allan Karam F.
Published: April 2022

Nano ZnO is biosynthesized using Lactobcillus sp. Poly Acrylic acid-co-Acrylonitrile/ZnO, PAACAN/ZnO, and poly Acrylic acid-co-Maleic acid/ZnO, PAACMA/ZnO, nancomposites were synthesized using 60Co γ-rays. PAACAN/ZnO and PAACMA/ZnO nanocomposites were characterized and used as sorbents for 60Co(II) radionuclide. The monolayer adsorption capacities of 60Co(II) onto PAACMA/ZnO and PAACAN/ZnO are 18.235, 7.105 mgg−1, respectively at pH 4.5 and 20 °C. The sorption reaction has a pseudo 2nd order mechanism. 0.1 M EDTA could be used as an eluent for desorption. The desorption efficiencies of 60Co(II) from PAACAN/ZnO and PAACMA/ZnO were 67.51 and 84.85%, respectively. The sorption process is endothermic and spontaneous.
Stress-Inducing and Anxiety-Ridden: A Practice-Based Approach to the Construction of Status-Bestowing Evaluations in Research Funding
Authors: Edlund Peter , Lammi Inti
Published: April 2022

More than resource allocations, evaluations of funding applications have become central instances for status bestowal in academia. Much attention in past literature has been devoted to grasping the status consequences of prominent funding evaluations. But little attention has been paid to understanding how the status-bestowing momentum of such evaluations is constructed. Throughout this paper, our aim is to develop new knowledge on the role of applicants in constructing certain funding evaluations as events with crucial importance for status bestowal. Using empirical material from retrospective interviews with Sweden-based early-career scientists who, successfully or unsuccessfully, applied for European Research Council (ERC) Starting Grants, our findings show how these scientists interlinked experiences from various practices to construct the ERC’s evaluations, in general, and the final-stage appointments at Brussels’ Madou Plaza Tower, in particular, as apex-esque, crescendo-like status-bestowing events. We discuss our findings as instructional, preparatory, and demarcative practices that, by extension, distribute responsibility for the construction and reinforcement of high-stakes, career-defining evaluations through which considerable stress and anxiety is generated in academia.
Vortices nucleation by inherent fluctuations in nematic liquid crystal cells
Authors: Aguilera Esteban , Clerc Marcel G. , Zambra Valeska
Published: April 2022

Multistable systems are characterized by exhibiting domain coexistence, where each domain accounts for the different equilibrium states. In case these systems are described by vectorial fields, domains can be connected through topological defects. Vortices are one of the most frequent and studied topological defect points. Optical vortices are equally relevant for their fundamental features as beams with topological features and their applications in image processing, telecommunications, optical tweezers, and quantum information. A natural source of optical vortices is the interaction of light beams with matter vortices in liquid crystal cells. The rhythms that govern the emergence of matter vortices due to fluctuations are not established. Here, we investigate the nucleation mechanisms of the matter vortices in liquid crystal cells and establish statistical laws that govern them. Based on a stochastic amplitude equation, the law for the number of nucleated vortices as a function of anisotropy, voltage, and noise level intensity is set. Experimental observations in a nematic liquid crystal cell with homeotropic anchoring and a negative anisotropic dielectric constant under the influence of a transversal electric field show a qualitative agreement with the theoretical findings.
Onion Vinegar Quality Evaluation and its Alleviate Oxidative Stress Mechanism in Caenorhabditis elegans Via SKN-1
Authors: Wang Jianfeng , Liu Xinhua , Hang Shuqin , Cao Chunxin , He Yucheng , Sun Xiaoming , Zheng Rongquan , Yuan Jianfeng
Published: April 2022

Recently, there has been renewed interest in biorefining of agricultural onion into functional products. In this study, onion vinegar (OV) are prepared by a two-stage semi-continuous fermentation method, and its content of total flavonoids (3.01 mg/mL) and polyphenols (976.76 μg/mL) is superior to other commercial vinegars. OV possesses a high radical scavenging activity and enhances the antioxidant enzyme activities in vivo, alleviating intracellular oxidative stress in Caenorhabditis elegans. Treated by OV, the 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH·), diammonium 2,2′-azino-bis (3-ethylbenzo thiazoline-6-sulfonic acid) (ABTS+·) and 2-phenyl-4,4,5,5- tetramethylimidazoline-1-oxyl 3-Oxide (PTIO·) free radicals clearance rates are 88.76, 98.76 and 90.54%, respectively in vitro. Whereas the glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) enzyme activities in C. elegans reach 271.57, 129.26, and 314.68%, respectively. Using RNAi and RT-PCR, it has been further confirmed that OV modulates transcription factor SKN-1, the nuclear factor erythroid 2-related factor 2 (Nrf2) homologous, in C. elegans, enhancing the resistance of C. elegans against sodium arsenite stress. Lifespan analysis reveals that 1 mL OV extends the maximum lifespan of the nematode to 26 days. Evidence is presented which shows that OV increases the lifespan of C. elegans by activating the SKN-1 signaling pathway. Overall, the OV is a well functional condiment, enhancing the value-added of onion.
The association between current earnings surprises and the ex post bias of concurrently issued management forecasts
Authors: Baginski Stephen P. , Campbell John L. , Ryu Patrick W. , Warren James D.
Published: April 2022

The vast majority of managers’ earnings forecasts are issued concurrently (i.e., bundled) with their firm’s current earnings announcement. We document a predictable bias in these forecasts—the forecasts fail to fully reflect the persistence of the current earnings surprise. Specifically, we find that managers issue (1) optimistically biased forecasts alongside negative earnings surprises and (2) pessimistically biased forecasts alongside large positive earnings surprises. Bayesian updating implies this bias could be unintentional, but we find that the bias is stronger when managers have greater incentives and fewer constraints to issue biased forecasts, suggesting that, to some extent, the bias might be intentional. Relatedly, although managers typically have better information about their firm’s earnings than analysts, we show that analyst reliance on these biased management forecasts represents a mechanism (and an alternative interpretation) for a similar analyst underreaction to current earnings attributed in the literature to analysts’ cognitive bias. We also find that, on average, investors do not appear to initially understand the bias in these forecasts but do unravel it over longer windows. However, investors more quickly unravel the bias when the manager has a history of issuing biased forecasts and when the firm has more sophisticated investors. Overall, we document that managers’ forecasts appear to repeatedly underweight the persistence of current earnings surprises, are biased in ways that improve investors’ perceptions of managers’ ability, and that this behavior concentrates in subsamples where outsiders have a harder time recognizing any bias.
On the role of monetary incentives in risk preference elicitation experiments
Authors: Hackethal Andreas , Kirchler Michael , Laudenbach Christine , Razen Michael , Weber Annika
Published: April 2022

Incentivized experiments in which individuals receive monetary rewards according to the outcomes of their decisions are regarded as the gold standard for preference elicitation in experimental economics. These task-related real payments are considered necessary to reveal subjects’ “true preferences.” Using a systematic, large-sample approach with three subject pools of private investors, professional investors, and students, we test the effect of task-related monetary incentives on risk preferences in four standard experimental tasks. We find no significant differences in behavior between and within subjects in the incentivized and non-incentivized regimes. We discuss implications for academic research and forions in the field.
Two New Methods for Counting and Tracking the Evolution of Polar Faculae
Authors: Hovis-Afflerbach B. , Pesnell W. Dean
Published: April 2022

Polar faculae are the footpoints of magnetic-field lines near the Sun’s poles that are seen as bright regions along the edges of granules. The time variation in the number of polar faculae has been shown to correlate with the strength of the polar magnetic field and to be a predictor of the subsequent solar cycle. Due to the small size and transient nature of these features, combined with different techniques and observational factors, previous counts of polar faculae differ in magnitude. Further, there were no scalable techniques to measure the statistical properties of the faculae, such as the variation of the facular lifetime with time or solar activity. Using data from the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO), we present two new methods for tracking faculae and measuring their properties. In the first, we calculate the pixel-by-pixel standard deviation of the HMI continuum intensity images over one day, visualizing the faculae as streaks. The lifetime of the facula is found by dividing the angular length of the streaks by the latitude-dependent rotation rate. We apply this method to the more visible pole each day for a week every six months, from September 2010 to March 2021. Combining all of the measured facular lifetimes provides a statistical distribution with a mean of 6.0 hours, a FWHM of 5.4 hours, and a skew towards longer lifetimes, with some faculae lasting up to 1 day. In the second method, we overlay images of the progressive standard deviation with the HMI magnetogram to show the close relationship between the facular candidates and the magnetic field. The results of this method allow us to distinguish between motion due to the Sun’s rotation and “proper motion” due to faculae moving across the Sun’s surface, confirming that faculae participate in convective motions at the poles. Counts of polar faculae using both methods agree with previous counts in their variation with the solar cycle and the polar magnetic field. These methods can be extended to automate the identification and measurement of other properties of polar faculae, which would allow for daily measurements of all faculae since SDO began operation in 2010.
Physical Activity and Exercise Addiction During the Covid-19 Pandemic in Italy
Authors: Ceci Franca , Di Carlo Francesco , Burkauskas Julius , Salone Anatolia , De Luca Ilaria , Cicconcelli Dorotea , Giorgetti Valentina , La Fratta Irene , Todaro Antonino , Simonato Pierluigi , Martinotti Giovanni , di Giannantonio Massimo , Corazza Ornella
Published: April 2022

Severe restrictive measures were implemented globally to limit the spread of the Covid-19 pandemic leading to significant lifestyle changes and impacting on both the physical and the mental health of citizens. Caught by the fear of getting sick, some individuals have adopted behaviors which favored the development of exercise addiction (EA). Our aim was to evaluate physical activity habits and the risk of EA in the general Italian population during phase 1 of the lockdown. The role of appearance anxiety (AA), self-compassion, and use of performance and image enhancing drugs (PIEDs) as predictors of EA development were investigated. A comparison between physically active subjects with the inactive ones was also included. Between April and May 2020, an online survey was conducted across Italy. Nine hundred thirty-six answers were collected. The rate of EA in the physically active sample (782 subjects) was 4.1%. The physically active group showed higher SCS scores and a greater use of PIEDs. Of the physically active participants, 84.2% reported variations in their fitness routine. Perceived benefit of exercising resulted significantly higher in those with EA. Subjects with EA reported stronger motivation in engaging in physical activity as for “physical wellness,” “psychological well-being,” and “sexual attractiveness and confidence in relationship.” A higher level of AA, a lower level of self-compassion, and a higher perceived benefit of exercising during lockdown were all significant predictors for the presence of EA. Our findings suggest that the fear of getting sick from Covid-19, combined with radical changes in the lifestyles induced by the lockdown and individual personological characteristics, can favor the development of EA and related phenomena in the general population.
The value relevance of digital marketing capabilities to firm performance
Authors: Homburg Christian , Wielgos Dominik M.
Published: April 2022

Digital transformation of the marketing organization forces firms to develop new digital marketing capabilities (DMCs) to remain competitive. However, despite considerable academic and managerial interest, the value relevance of DMCs beyond the value achieved through classic marketing capabilities (CMCs) remains unclear. Similarly, research investigating the interaction effect of DMCs and CMCs is scarce. We address both research gaps by drawing on a mixed-methods approach combining in-depth interviews and a multi-industry, multisource dataset. The results reveal that DMCs significantly contribute to firm profitability beyond the influence of CMCs. Drawing on the contingent view of resource-based theory, we investigate the moderating influence of organizational and environmental contingencies on the interaction effect of DMCs and CMCs. This investigation reveals important tradeoffs that result in actionable managerial implications for realizing the complementarity potential—and preventing the substitutive potential—of a firm’s DMCs and CMCs.
Effects of predator novelty on intraguild predation communities with adaptive prey defense
Authors: Ingeman Kurt E. , Novak Mark
Published: April 2022

Understanding coexistence within community modules such as intraguild predation (IGP), where an omnivore both preys on and competes with an intermediate consumer for a shared resource, has provided insight into the mechanisms that promote the persistence of complex food webs. Adaptive, predator-specific defense has been shown theoretically to enhance coexistence of IGP communities when employed by shared prey. Yet to date, all such theory has assumed that prey have an accurate perception of predation risk and appropriate antipredator responses, assumptions that may not be justified when considering a novel predator. We therefore consider the effects of an introduced predator on IGP coexistence, describing two invasion scenarios: suboptimal defense, whereby a similar invader elicits an ineffective antipredator response; and naïveté toward an unfamiliar invader, for which prey fail to accurately estimate predation risk. We examine predictions for native predator persistence across gradients of enrichment and defense costs. The model predicts that predator novelty can weaken the effect of adaptive defense, causing exclusion of native predators that would persist in the absence of novelty and inducing unstable dynamics in previously stable regions of parameter space. Coexistence is predicted to be more sensitive to the effects of suboptimal defense than to naïveté, and differentially leads to the exclusion of native predators in highly productive environments and when defense costs are low. Moderate novelty of the omnivore can increase resource density via a trophic cascade, while consumer novelty can either lead to omnivore exclusion or facilitate three-species coexistence by providing a subsidy to the otherwise excluded native omnivore. Our analyses suggest that models of adaptive defense are sensitive to assumptions regarding predator–prey eco-evolutionary experience and that predator novelty has significant implications for food web dynamics.
Snakehead: the extent to which Chinese organised crime groups are involved in human smuggling from China to the UK
Authors: Whittle Joseph
Published: April 2022

With human smuggling, trafficking and associated areas such as modern slavery consistently in the news over the past decade governments have established and reinforced a narrative whereby evil organised criminals are responsible for driving the numbers of people migrating. This despite much academic evidence to contrary. Snakeheads have long been linked to facilitating human smuggling from China and tick all the stereotypical boxes for an organised crime ‘folk devil’. An ominous name; shadowy methods; allegedly highly exploitative and a reassuringly ‘foreign’ threat, Snakeheads fit neatly into the narrative above. Using a range of sources including qualitative interviews, survey data, Government statistics and Freedom of Information Requests this this paper suggests the reality is very different. That Snakeheads do not fit snuggly with media and government perceptions of who smuggles people from China or how they interact with organised crime. It suggests that the smuggling from China is not overseen by nefarious organised crime groups but criminal entrepreneurs.
Nodes of tension: negotiating epistemic fluency in interdisciplinary co-teaching
Authors: Colton Jill , Mignone Joanne , Newport-Peace Diana
Published: April 2022

This paper is about interdisciplinary collaboration in a higher education context. The authors have investigated their own experiences of interdisciplinary collaboration through reflexive autobiographical narrative writing and co-generative dialogue. The experience of working in a project which brought together students from different parts of the university was analysed with reference to critical readings about interdisciplinary work. The authors have identified moments of boundary crossing or ‘nodes of tension’ through which relationships were being negotiated and knowledge was being produced. The analysis of these moments shows that interdisciplinary work is intensely relational and dialogic; it takes time and involves significant labour. The authors contend that this labour is essential to building trust and openness to what is unfamiliar, and that universities which seek to promote interdisciplinary collaboration must acknowledge the significant additional work necessary to negotiate nodes of tension.
Inactive Al3+-doped La(CoCrFeMnNiAlx)1/(5+x)O3 high-entropy perovskite oxides as high performance supercapacitor electrodes
Authors: Guo Meng , Liu Yufeng , Zhang Fengnian , Cheng Fuhao , Cheng Chufei , Miao Yang , Gao Feng , Yu Jun
Published: April 2022

A series of high-entropy perovskite oxides (HEPOs) La(CoCrFeMnNiAlx)1/(5+x)O3−δ (x = 0.4, 0.5, 0.6, and 0.7) have been synthesized by coprecipitation method combined with calcination process and explored as electrodes for supercapacitors. The crystal structure, microstructure, and elemental composition of HEPOs were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS) in detail. The electrochemical properties of HEPOs as supercapacitor electrodes were elucidated. The specific capacitances of HEPOs (x = 0.4, 0.5, 0.6, and 0.7) are 281.84, 353.65, 325.60, and 259.30 F/g at the current density of 1 A/g, respectively. After 2000 cycles, the specific capacitances of HEPOs (x = 0.4, 0.5, 0.6, and 0.7) remain 85.01%, 88.61%, 86.37%, and 91.25%, respectively. Such outstanding electrochemical properties can be attributed to the entropy-stabilized structure caused by mixed six cations in B-site and the Al3+-doping suppressing active ion aggregation during charge—discharge process. This research highlights the potential of HEPOs as electrodes for supercapacitors.
Interior-collapsing mechanism by hydrothermal process of the MgAl2O4/MgO porous ceramic
Authors: Yao Yao , Zhang Yue
Published: April 2022

Ceramic core is a critical component in the super-alloy turbine blade casting. In our previous work, a novel multi-phase MgAl2O4/MgO porous ceramic was prepared for this purpose. The most important property was that it crumbled completely after hydrothermal treatment in just pure water, due to the hydration of MgO. In this work, the hydration process of the MgO embedded in the inert matrix was investigated in detail. The collapse behaved as an interior destruction without any bulk expansion of the sample. The hydration percentage was the only factor related to the water-collapsibility. The morphology of hydration product indicated that the reaction advanced in particular direction. Based on the finite element analysis for the expansion effect on the porous structure, the interior-collapsing mechanism was proposed. During the hydration process, the MgO grains exerted pressure to the surrounding matrix and induced the collapse in the adjacent structure. This process took place throughout the matrix. Finally, the sample crumbled completely to the powders. No bulk dilatation was detected before the powdering, indicating that the collapse process would not exert pressure outward. Thus the alloy blade would not be damaged during the removal of the ceramic core. It was also predicted that the decrease in the MgO grain size was beneficial to the water-collapsibility.
Wie können Lehramtsstudierende bei der wissenschaftsbasierten Reflexion selbsterlebter schulischer Situationen unterstützt werden? Eine quasi-experimentelle Studie zur Lernwirksamkeit von Prompts und Feedback im Praxissemester
Authors: Schellenbach-Zell Judith
Published: April 2022

Der vorliegende Beitrag greift aktuelle Fragen der Forschung zur Theorie-Praxis-Verknüpfung im Rahmen von Praxisphasen auf und legt den Fokus auf Instrumente der Lernbegleitung, die die Nutzung von Theorien und Befunden bei der Erklärung selbstgewählter schulischer Situationen unterstützen sollen. Diese Reflexion praktischer Situationen erfolgt schriftlich fixiert im Rahmen von Lerntagebüchern. Das untersuchte Instrument enthält zum einen strukturierende Hinweise in Form von Prompts sowie zum anderen ein nachträgliches leitfadengestütztes Feedback durch die begleitenden Dozierenden. Entsprechend werden drei Gruppen in der Lernbegleitung durch das Praxissemester im Master of Education quasi-experimentell miteinander verglichen: Während die erste Experimentalgruppe nur strukturierende Hinweise (Prompts) erhielt, wurden diese für die zweite Experimentalgruppe mit leitfadengestütztem Feedback durch die Dozierenden kombiniert. Die Kontrollgruppe erhielt allgemeine Hinweise zur Reflexion der schulischen Situation. Die Ergebnisse zeigen, dass sich der Einsatz von Prompts und Feedback in der Lernbegleitung positiv auf die Verwendung von Theorien und Befunden bei der Erklärung von schulischen Situationen auswirkt.
Rights, Mini-Publics, and Judicial Review
Authors: GJESDAL ADAM
Published: April 2022

Landmark Supreme Court rulings determine American law by adjudicating among competing reasonable interpretations of basic political rights. Jeremy Waldron argues that this practice is democratically illegitimate because what determines the content of basic rights is a bare majority vote of an unelected, democratically unaccountable, elitist body of nine judges. I argue that Waldron's democratic critique of judicial review has implications for real-world reform, but not the implications he thinks it has. He argues that systems of legislative supremacy over the judiciary are democratically preferable to the American one. I provide reasons why his argument is unsound and explain that, properly construed, Waldron's premises support implementing a system where ordinary citizens chosen by lottery participate in a deliberative mini-public to vote on which reasonable interpretation of a basic political right will become the law of the land.
Dancehall City: Zongo Identity and Jamaican Rude Performance in Ghanaian Popular Culture
Authors: Alleyne Osei
Published: April 2022

The explosion of Ghanaian Reggae-Dancehall reflects the influence of Jamaican-inspired popular culture in Ghana today. This subculture is championed by local Rastafarians and by youth from the zongos (internal migrant, largely Islamic, unplanned neighborhoods). Suffering social alienation, many zongo artists have adopted postures similar to their Jamaican counterparts—mirroring Rasta and rude identities as counter-hegemonic resistance. Alleyne explores several artists variously located between the zongo, the Reggae diaspora, and the Ghanaian state, examining how subjects rework Jamaican tropes and voice their aspirations within a globalizing Ghana and rethinking the zongo as space of rousing diasporic consciousness.
Bringing to Scale: The Scaling-Up Concept in African Agricultural Value Chains
Authors: Bassett Thomas J. , Koné Moussa , Munro William
Published: April 2022

The concept of “scaling up” value chains dominates the African agricultural development literature. Scaling up commonly refers to three inter-related objectives: increasing agricultural production and quality, expanding farmer engagement with markets, and adding greater value to commodities that benefits all actors. Bassett, Koné, and Munro provide a critique of the assumption of linear and progressive development embedded in the scaling-up concept and offer an alternative relational network approach that highlights the contingent and relational dynamics of agricultural value chains. The research compares the selling patterns of cashew growers participating in OLAM’s Sustainable Cashew Growers Program in Côte d’Ivoire during 2018 and 2019.
Objetos de cobre arsenical y sociedades agropastoriles en la Puna Meridional argentina: Nuevas perspectivas sobre la metalurgia del segundo milenio aP en los Andes centro sur
Authors: Babot Pilar , Gonzalez Baroni Lucia G. , Becerra María Florencia
Published: April 2022

Se presenta el primer análisis composicional, morfológico y contextual de objetos metálicos de la Puna Meridional argentina (1430-2070 aP) para contribuir al conocimiento de la metalurgia centro-surandina del cobre, desde un espacio marginal a los principales centros productivos relacionados con esta tecnología. Mediante microscopia electrónica de barrido y análisis de energía dispersiva de rayos X (MEB-EDS) se identifican cobres sin alear y aleaciones de cobre-arsénico y de plomo-arsénico, con una variedad de elementos minoritarios que corresponderían a distintas menas y, potencialmente, distintos lugares de producción en los Andes centro sur. El metal habría circulado a largas distancias en distintos trayectos en el marco de las redes sociales que vincularon ámbitos a diferentes alturas en ambas vertientes andinas. La Puna Meridional constituiría un nodo en esta circulación durante el período Medio. Allí el metal se integró a rituales domésticos del grupo corresidente de fundación, de clausura y referidos al ciclo anual agropastoril, mediante los cuales se propiciarían sus animales domésticos y se reclamaría el territorio.
The Mystery of the Missing Horses: How to Uncover an Ottoman Shadow Economy
Authors: Koh Choon Hwee
Published: April 2022

In the 1690s, Ottoman bureaucrats reformed the sprawling postal system, a vital communications infrastructure that undergirded imperial power. Despite the expanding monitoring capacity that resulted, a constant shortage of horses regularly left couriers stranded for days and delayed official correspondence. This essay investigates this paradox and draws on a series of fifty-one Ottoman imperial decrees and reports from 1690 to 1833 to make three arguments. It first shows how bureaucrats perceived and tried to fix the problem by rationing horse usage and strengthening enforcement of rules. Second, it reveals that a range of official and non-official actors were diverting horses toward profit-making ventures in what I call a “shadow economy.” Third, it explains why Ottoman bureaucrats were unable to recognize the existence of this shadow economy. Like contemporary administrators in Qing China who found it hard to synthesize intelligence from different frontiers, Ottoman bureaucrats treated multiple reports of missing horses as discrete, unconnected events rather than connected evidence of a competing market demand for horses. Compounding this problem of a blinkered informational order, profound economic and social changes meant that bureaucrats in the capital were slow to realize that long-held official entitlements regarding horse usage for personal uses were aiding the growth of the shadow economy. I conclude by considering some social consequences of commercial forces in Ottoman society and contemporary France, and the stakes of this study with respect to the rise of anonymity in market exchanges, a property of capitalism.