bluuebunny/crossref_metadata_2025 huggingface dataset:
Towards estimating affective states in Virtual Reality based on behavioral data
Authors: Holzwarth Valentin , Schneider Johannes , Handali Joshua , Gisler Joy , Hirt Christian , Kunz Andreas , vom Brocke Jan
Published: April 2021

Inferring users’ perceptions of Virtual Environments (VEs) is essential for Virtual Reality (VR) research. Traditionally, this is achieved through assessing users’ affective states before and after being exposed to a VE, based on standardized, self-assessment questionnaires. The main disadvantage of questionnaires is their sequential administration, i.e., a user’s affective state is measured asynchronously to its generation within the VE. A synchronous measurement of users’ affective states would be highly favorable, e.g., in the context of adaptive systems. Drawing from nonverbal behavior research, we argue that behavioral measures could be a powerful approach to assess users’ affective states in VR. In this paper, we contribute by providing methods and measures evaluated in a user study involving 42 participants to assess a users’ affective states by measuring head movements during VR exposure. We show that head yaw significantly correlates with presence, mental and physical demand, perceived performance, and system usability. We also exploit the identified relationships for two practical tasks that are based on head yaw: (1) predicting a user’s affective state, and (2) detecting manipulated questionnaire answers, i.e., answers that are possibly non-truthful. We found that affective states can be predicted significantly better than a naive estimate for mental demand, physical demand, perceived performance, and usability. Further, manipulated or non-truthful answers can also be estimated significantly better than by a naive approach. These findings mark an initial step in the development of novel methods to assess user perception of VEs.
Environmental aspects and economic evaluation of new green hydrolysis method for waste feather processing
Authors: Solcova Olga , Knapek Jaroslav , Wimmerova Lenka , Vavrova Kamila , Kralik Tomas , Rouskova Milena , Sabata Stanislav , Hanika Jiri
Published: April 2021

In recent years, an increase in the chicken meat process industry has been growing quickly, which brings a large amount of difficult to process waste, chicken feathers. These billions of kilograms create a serious waste problem over the world, furthermore, poultry feather processing is not only particularly difficult but also relatively expensive. In fact, there is no technology suitable for processing such huge quantities of feathers to guarantee sustainable development of the chicken meat industry together with processing of waste feathers. This article introduces a newly designed and original, highly efficient and environmentally friendly method of physicochemical hydrolysis of waste feathers. The hydrolysis is carried out in the presence of a weak organic carboxylic acid; thus, the resulting hydrolysate does not contain any salts or ashes. Therefore, a resulting hydrolysate, which includes a mixture of amino acids, peptides, proteins, glycoproteins and free fatty acids, is suitable for a variety of applications; e.g. as a chondroprotective agent in the treatment of joint diseases, nutrients for crop plants or targeted biostimulants for agriculture. This paper is focused not only on the process scale-up but also on environmental aspects and economic evaluations to bring general view of the process.

Graphic abstract
Mass media coverage and vaccination uptake: evidence from the demand for meningococcal vaccinations in Hungary
Authors: Bíró Anikó , Szabó-Morvai Ágnes
Published: April 2021

We estimate the effect of mass media coverage of the meningococcal disease on the uptake of meningococcal vaccinations in Hungary. Our analysis is based on administrative county-level data on vaccination purchases linked to indicators of media coverage of the meningococcal disease and to administrative records of disease incidence. Using geographical and time variations in these indicators, our fixed effects estimates indicate a strong positive effect of mass media coverage of the disease on the rate of vaccination with all types of the meningococcal vaccine. At the same time, we do not find evidence that disease incidence itself has a positive impact on vaccination. These findings are broadly in line with imperfect information and the principles of bounded rationality and highlight the responsibility of mass media in influencing health-related behaviours.
Correction to: The biotechnological importance of the plant-specific NAC transcription factor family in crop improvement
Authors: Singh Sadhana , Koyama Hiroyuki , Bhati Kaushal K. , Alok Anshu
Published: April 2021

The article The biotechnological importance of the plant-specific NAC transcription factor family in crop improvement, written by Sadhana Singh, Hiroyuki Koyama, Kaushal K. Bhati and Anshu Alok, was originally published electronically on the publisher’s internet portal on February 22, 2021 without open access.
Investigating the determinants of vaccine hesitancy within undergraduate students’ social sphere
Authors: Siani Alessandro , Driscoll Megan , Hurst Tia-mai , Coker Tutu , Grantham Alice Georgina , Bunet Amrit
Published: April 2021

Aims

Vaccine hesitancy is widely recognised as one of the most serious threats to current global health. While the causes underlying vaccine hesitancy have been extensively described and several mitigation strategies trialled amongst current and prospective parents, there is a relative scarcity of research investigating its extent and causative factors amongst university students, a critical demographic due to its temporal proximity to the average child-rearing age. The present study sought to address this literature gap by elucidating the social and demographic factors that might underpin vaccine hesitancy in university students.

Subject and methods

An anonymous online survey was carried out to investigate the opinions and perspectives on the practice of vaccination within undergraduate students’ social sphere. The statistical significance of the differences observed between groups of participants was analysed using non-parametric tests of variance.

Results

Amongst the 739 volunteers who participated in the survey, vaccine confidence varied significantly (p < 0.001) with age, ethnicity and religion, and to a lesser (yet still statistically significant) extent (p < 0.05) with graduate status. No statistically significant differences were observed with regard to gender or number of children.

Conclusions

By shedding new light on the factors underpinning vaccine hesitancy within undergraduate students’ social network, the present study provides a stepping stone towards the development of targeted mitigation strategies.
Structuring Communication Effectively—The Causal Effects of Communication Elements on Cooperation in Social Dilemmas
Authors: Koessler Ann-Kathrin , Ortiz-Riomalo Juan Felipe , Janke Mathias , Engel Stefanie
Published: April 2021

Many environmental problems represent social dilemma situations where individually rational behaviour leads to collectively suboptimal outcomes. Communication has been found to alleviate the dilemma and stimulate cooperation in these situations. Yet, the knowledge of the basic elements, i.e. the types of information that need to be provided and exchanged to make communication effective, is still incomplete. Previous research relies on ex post methods, i.e. after conducting an experiment researchers analyse what information was shared during the communication phase. By nature, this ex post categorization is endogenous. In this study, we identify the basic elements of effective communication ex ante and evaluate their impact in a more controlled way. Based on the findings of previous studies, we identify four cooperation-enhancing elements of communication: (i) problem awareness, (ii) identification of strategies, (iii) agreement, and (iv) ratification. In a laboratory experiment with 560 participants, we implement interventions representing these components and contrast the resulting levels of cooperation with the outcomes under free (unstructured) or no communication. We find that the intervention facilitating agreement on a common strategy (combination of (ii) and (iii)) is particularly powerful in boosting cooperation. And if this is combined with interventions promoting problem awareness and ratification, similar cooperation levels as in settings with free-form communication can be reached. Our results are relevant not only from an analytical perspective, but also provide insights for social dilemma situations in which effective communication processes cannot be successfully self-organized, calling for some form of external, structured facilitation or moderation.
Comparison of three sampling methods for small-bodied fish in lentic nearshore and open water habitats
Authors: Merz Joseph E. , Anderson Jesse T. , Wiesenfeld Jesse , Zeug Steven C.
Published: April 2021

We performed a preliminary evaluation of a mobile sampling platform with adjustable push net and live box (Platform) against two common methods for sampling small-bodied fish (i.e., 10–100 mm) in two distinct lentic habitats. Nearshore (NS) littoral habitat was sampled by Platform and beach seine, and open water (OW) pelagic habitat by Platform and Kodiak trawl. Our goal was to evaluate the Platform’s ability to describe fish assemblage structure across habitat types in contrast to common techniques restricted to single habitat types that are less comparable due to gear-specific bias. Platform sample speed had a significant positive effect on recapture efficiency of both nearly neutrally buoyant objects and marked fish. Marked fish recapture efficiencies were similar for Platform in NS and OW, indicating similar efficiency across habitat types. Platform capture efficiency was similar to beach seine and greater than Kodiak trawl. With similar sampling time, the Platform collected more individuals and taxa in NS relative to beach seine and in OW relative to Kodiak trawl. Greater taxa detection by the Platform suggests that it may be effective at detecting species that are numerically rare in specific habitats when compared to these methods. Fish CPUE was significantly greater NS regardless of technique. However, by using the Platform, there is greater confidence that this difference was reliable and not a gear selectivity artifact. Overall, this preliminary study demonstrates the Platform’s potential to collect standardized data across NS and OW habitats, track ontogenetic habitat shifts, and detect differences in small-bodied fish taxa richness, relative abundance, and density between NS and OW habitats. Continued experimentation beyond a single reservoir and fish size range is required before consensus can be established regarding the utility of this new push net design.
Statistically responsible artificial intelligences
Authors: Smith Nicholas , Vickers Darby
Published: April 2021

As artificial intelligence (AI) becomes ubiquitous, it will be increasingly involved in novel, morally significant situations. Thus, understanding what it means for a machine to be morally responsible is important for machine ethics. Any method for ascribing moral responsibility to AI must be intelligible and intuitive to the humans who interact with it. We argue that the appropriate approach is to determine how AIs might fare on a standard account of human moral responsibility: a Strawsonian account. We make no claim that our Strawsonian approach is either the only one worthy of consideration or the obviously correct approach, but we think it is preferable to trying to marry fundamentally different ideas of moral responsibility (i.e. one for AI, one for humans) into a single cohesive account. Under a Strawsonian framework, people are morally responsible when they are appropriately subject to a particular set of attitudes—reactive attitudes—and determine under what conditions it might be appropriate to subject machines to this same set of attitudes. Although the Strawsonian account traditionally applies to individual humans, it is plausible that entities that are not individual humans but possess these attitudes are candidates for moral responsibility under a Strawsonian framework. We conclude that weak AI is never morally responsible, while a strong AI with the right emotional capacities may be morally responsible.
Long-term fate of fertilizer sulfate- and elemental S in co-granulated fertilizers
Authors: Degryse Fien , Baird Roslyn , Andelkovic Ivan , McLaughlin Michael J.
Published: April 2021

In previous studies, we assessed sulfur (S) uptake by crops from elemental S (ES) and sulfate-S (SO4-S) in S-fortified monoammonium phosphate fertilizers over two years. The recovery by the crop ranged from 16 to 28% for ES and from 9 to 86% for SO4-S. Here, we used a model which takes into account organic S cycling, SO4-S leaching and ES oxidation to explain the observed recoveries. Higher recoveries of ES than SO4-S in two of the four sites could be explained by partial leaching of SO4-S and relatively fast oxidation of ES, due to a warm climate and high S-oxidizing soils. The same model was used for longer-term (5-year) predictions, and a sensitivity analysis was carried out. The size of the labile soil S pool and total S uptake strongly affected the recovery of both SO4-S and ES. Predicted recoveries after 5 years were over threefold higher for a small than for a large labile organic S pool and for a high-uptake than for a low-uptake scenario. Leaching mainly affected SO4-S, with predicted recoveries halved under a high-leaching scenario. Slow oxidation resulted in recoveries in the first year being fourfold lower for ES than for SO4-S or even lower in case of a long lag-time. However, it is predicted that total recoveries of ES will eventually reach those of SO4-S or exceed them if there is SO4-S leaching. Our model demonstrates that long-term trials are needed to evaluate the true effectiveness of a slow-release fertilizer source such as ES.
Adapting Bodies to Infrastructures
Authors: Schindler Larissa
Published: April 2021

The material interrelations between bodies and objects are a wide, worthwhile and absorbing field, which has not been sufficiently examined yet. Focusing on such interrelations within air travel, this article contributes to the exploration of this field. It delineates that such interrelations do not simply happen, but that they have to be accomplished continuously by different participants with a certain risk to fail at many points. Within mobilities, such processes of interrelating occur under the specific circumstances of a moving vehicle. Based on empirical data from an ethnographic study on air travel, the paper is concerned with the ongoing dynamics of body-object-interrelations. Based on this analysis, it suggests emphasizing the continuous modification that material assemblages built of people and objects undergo even when “only” staying immobile during a flight. Passengers do not simply enter and exit a vehicle staying identical with themselves. Rather, they are continuously adapting to a material infrastructure that shapes and adjusts their corporeal needs and capacities, including their senses.
Automatic discovery of interpretable planning strategies
Authors: Skirzyński Julian , Becker Frederic , Lieder Falk
Published: April 2021

When making decisions, people often overlook critical information or are overly swayed by irrelevant information. A common approach to mitigate these biases is to provide decision-makers, especially professionals such as medical doctors, with decision aids, such as decision trees and flowcharts. Designing effective decision aids is a difficult problem. We propose that recently developed reinforcement learning methods for discovering clever heuristics for good decision-making can be partially leveraged to assist human experts in this design process. One of the biggest remaining obstacles to leveraging the aforementioned methods for improving human decision-making is that the policies they learn are opaque to people. To solve this problem, we introduce AI-Interpret: a general method for transforming idiosyncratic policies into simple and interpretable descriptions. Our algorithm combines recent advances in imitation learning and program induction with a new clustering method for identifying a large subset of demonstrations that can be accurately described by a simple, high-performing decision rule. We evaluate our new AI-Interpret algorithm and employ it to translate information-acquisition policies discovered through metalevel reinforcement learning. The results of three large behavioral experiments showed that providing the decision rules generated by AI-Interpret as flowcharts significantly improved people’s planning strategies and decisions across three different classes of sequential decision problems. Moreover, our fourth experiment revealed that this approach is significantly more effective at improving human decision-making than training people by giving them performance feedback. Finally, a series of ablation studies confirmed that our AI-Interpret algorithm was critical to the discovery of interpretable decision rules and that it is ready to be applied to other reinforcement learning problems. We conclude that the methods and findings presented in this article are an important step towards leveraging automatic strategy discovery to improve human decision-making. The code for our algorithm and the experiments is available athttps://github.com/RationalityEnhancement/InterpretableStrategyDiscovery.
Evaluating risks-based communities of Mafia companies: a complex networks perspective
Authors: Castellano Nicola Giuseppe , Cerqueti Roy , Franceschetti Bruno Maria
Published: April 2021

This paper presents a data-driven complex network approach, to show similarities and differences—in terms of financial risks—between the companies involved in organized crime businesses and those who are not. At this aim, we construct and explore two networks under the assumption that highly connected companies hold similar financial risk profiles of large entity. Companies risk profiles are captured by a statistically consistent overall risk indicator, which is obtained by suitably aggregating four financial risk ratios. The community structures of the networks are analyzed under a statistical perspective, by implementing a rank-size analysis and by investigating the features of their distributions through entropic comparisons. The theoretical model is empirically validated through a high quality dataset of Italian companies. Results highlights remarkable differences between the considered sets of companies, with a higher heterogeneity and a general higher risk profiles in companies traceable back to a crime organization environment.
Lustre I/O performance investigations on Hazel Hen: experiments and heuristics
Authors: Seiz Marco , Offenhäuser Philipp , Andersson Stefan , Hötzer Johannes , Hierl Henrik , Nestler Britta , Resch Michael
Published: April 2021

With ever-increasing computational power, larger computational domains are employed and thus the data output grows as well. Writing this data to disk can become a significant part of runtime if done serially. Even if the output is done in parallel, e.g., via MPI I/O, there are many user-space parameters for tuning the performance. This paper focuses on the available parameters for the Lustre file system and the Cray MPICH implementation of MPI I/O. Experiments on the Cray XC40 Hazel Hen using a Cray Sonexion 2000 Lustre file system were conducted. In the experiments, the core count, the block size and the striping configuration were varied. Based on these parameters, heuristics for striping configuration in terms of core count and block size were determined, yielding up to a 32-fold improvement in write rate compared to the default. This corresponds to 85 GB/s of the peak bandwidth of 202.5 GB/s. The heuristics are shown to be applicable to a small test program as well as a complex application.
The Lord's Resistance Army
Authors: Schomerus Mareike
Published: April 2021

The Lord's Resistance Army (LRA) is one of Africa's most notorious armed rebel groups, having operated across Uganda, South Sudan, Sudan, the Central African Republic and the Democratic Republic of the Congo. When they entered the Juba Peace Talks with the Ugandan Government in 2006, the peace deal seemed like a gift to fighters who had for years barely been surviving in Central Africa's jungles. Yet the talks failed. Why? Based on exclusive interviews with LRA fighters and their notorious leader Joseph Kony, Mareike Schomerus provides insights into how the LRA experienced the Juba Talks, revealing developing dynamics and deep distrust within a conflict system and how these became entrenched through the peace negotiations. In so doing, Schomerus offers an explanation as to why current approaches to ending armed violence not only fail but how they actively contribute to their own failure, and calls for a new approach to contemporary peacemaking.
New Private Law Theory
Authors: Grundmann Stefan , Micklitz Hans , Renner Moritz
Published: April 2021

New Private Law Theory opens a new pathway to private law theory through a pluralistic approach. Such a theory needs a broad and stable foundation, which the authors have built here through a canon of nearly seventy texts of reference. This book brings these different texts from different disciplines into conversation with each other, grouping them around central questions of private law and at the same time integrating them with the legal doctrinal analysis of example cases. This book will be accessible to both experienced and early career scholars working on private law.
Power Shift
Authors: Newell Peter
Published: April 2021

Energy transitions are fundamental to achieving a zero-carbon economy. This book explains the urgently needed transition in energy systems from the perspective of the global political economy. It develops an historical, global, political and ecological account of key features of energy transitions: from their production and financing, to how they are governed and mobilised. Informed by direct engagement in projects of energy transition, the book provides an accessible account of the real-world dilemmas in accelerating transitions to a low carbon economy. As well as changes to technology, markets, institutions and behaviours, Power Shift shows that shifts in power relations between and within countries, and across social groups and political actors, are required if the world is to move onto a more sustainable path. Using contemporary and historical case studies to explore energy transitions, it will be of interest to students and researchers across disciplines, policymakers and activists.
Organ-building in Georgian and Victorian England
Authors: Thistlethwaite Nicholas
Published: April 2021

The London firm of Gray (later Gray & Davison) was one of Britain's leading organ-makers between the 1790s and the 1880s.
The Concept of “the Establishment” and the Transformation of Political Argument in Britain since 1945
Authors: Middleton Stuart
Published: April 2021

This article examines the formation and development of the concept of the Establishment in British political argument after its recoining in a celebrated article by the journalist Henry Fairlie in 1955. The author argues that the term “the Establishment” did not have a stable referent but rather acquired a range of possible meanings and uses as part of a new political vocabulary within which the course and significance of recent political and social change was contested, and that ultimately transformed social-democratic and conservative politics in Britain. The article situates the formation of the concept of the Establishment within a prolonged contestation of social and political authority in Britain during the middle of the twentieth century and traces the recoining of the term in conservative political commentary prior to Henry Fairlie's frequently cited 1955 Spectator article. From the late 1950s, it is argued, the concept acquired more distinctively contemporary meanings that enabled its adoption by Harold Wilson during the mid-1960s and its subsequent reappropriation by Margaret Thatcher in the mid-1970s. These usages registered and helped to accomplish fundamental political realignments, the understanding of which depends upon a close analysis of political and social concepts.
The genetics of late maturity alpha-amylase (LMA) in North American spring wheat (Triticum aestivum L.)
Authors: Liu Chang , Parveen Rehana S. , Revolinski Samuel R. , Garland Campbell Kimberly A. , Pumphrey Michael O. , Steber Camille M.
Published: April 2021

Genetic susceptibility to late maturity alpha-amylase (LMA) in wheat (Triticum aestivum L.) results in increased alpha-amylase activity in mature grain when cool conditions occur during late grain maturation. Farmers are forced to sell wheat grain with elevated alpha-amylase at a discount because it has an increased risk of poor end-product quality. This problem can result from either LMA or preharvest sprouting, grain germination on the mother plant when rain occurs before harvest. Whereas preharvest sprouting is a well-understood problem, little is known about the risk LMA poses to North American wheat crops. To examine this, LMA susceptibility was characterized in a panel of 251 North American hard spring wheat lines, representing ten geographical areas. It appears that there is substantial LMA susceptibility in North American wheat since only 27% of the lines showed reproducible LMA resistance following cold-induction experiments. A preliminary genome-wide association study detected six significant marker-trait associations. LMA in North American wheat may result from genetic mechanisms similar to those previously observed in Australian and International Maize and Wheat Improvement Center (CIMMYT) germplasm since two of the detected QTLs, QLMA.wsu.7B and QLMA.wsu.6B, co-localized with previously reported loci. The Reduced height (Rht) loci also influenced LMA. Elevated alpha-amylase levels were significantly associated with the presence of both wild-type and tall height, rht-B1a and rht-D1a, loci in both cold-treated and untreated samples.
Multi‐Layer Seismic Anisotropy Beneath Greenland
Authors: Nathan Erica M. , Hariharan Anant , Florez Darien , Fischer Karen M.
Published: April 2021

Seismic anisotropy provides insight into past episodes of lithospheric deformation and the orientations of strain in the underlying asthenosphere. The Greenland mantle has played host to a rich history of tectonic processes, including multiple orogenies and plume‐lithosphere interactions. This study presents new measurements of SKS splitting that reveal strong variations in fast polarization direction with back‐azimuth that are consistent across Greenland, including at stations where splitting measurements have not previously been reported. We compared observed fast polarization directions to the predictions of two‐layer models with olivine‐orthopyroxene anisotropy. The family of models that provides acceptable misfits at 95% confidence indicates an upper layer olivine a‐axis azimuth of 222–236°, a lower layer olivine a‐axis azimuth of 114–130°, and non‐zero a‐axis plunges. These models are consistent with an upper layer of lithospheric anisotropy due to Proterozoic and Archean orogenic fabrics, and a lower layer of anisotropy corresponding to either asthenospheric flow aligned approximately parallel to the direction of absolute plate motion and plunging due to lithospheric topography or dipping lithospheric structures created by episodes of paleo‐convergence.
Parker Solar Probe FIELDS Instrument Charging in the Near Sun Environment: Part 1: Computational Model
Authors: Diaz‐Aguado M. F. , Bonnell J. W. , Bale S. D. , Wang J. , Gruntman M.
Published: April 2021

The Spacecraft Interaction Plasma Software package (SPIS), a three‐dimension particle in cell (PIC) code, was used to model the Parker Solar Probe (PSP) spacecraft and FIELDS instrument and their interactions with the Solar wind. Our SPIS modeling relied on material properties of new spacecraft materials that we had obtained in previous work. The model was used to find the floating potentials of the spacecraft and FIELDS antennas at different distances from the Sun (from 1AU to 0.046AU). We find the following results: At greater distances from the Sun, the shadowed spacecraft charges negatively while the illuminated Thermal Protection System (TPS) charges positive due to the high resistance of the TPS Alumina shield at low temperatures. As the spacecraft approaches the Sun, the temperature of the TPS increases, the resistance between it and the spacecraft drops, and its photoemission increases, driving the spacecraft more positive. At the same time, an electrostatic barrier forms near the illuminated surface of the TPS and reflects the photoelectrons back leading to negative charging of some surfaces. The FIELDS antennas and shield also see this barrier forming but on a smaller scale. The FIELDS antennas charge positively at all distances modeled when no current bias is applied. Current biasing of the antennas affects their floating potential.
The Brittle‐Ductile Transition in Porous Limestone: Failure Mode, Constitutive Modeling of Inelastic Deformation and Strain Localization
Authors: Baud Patrick , Hall Stephen , Heap Michael J. , Ji Yuntao , Wong Teng‐fong
Published: April 2021

Understanding of the mechanics of the brittle‐ductile transition (BDT) in porous limestone is significantly more challenging than for sandstone because of the lack of consistent acoustic emission activity in limestone, meaning that one must rely on alternative techniques. In this paper, we investigate systematically the failure modes in Indiana limestone using X‐ray microComputed Tomography imaging (μCT) and Digital Volume Correlation (DVC). Our new mechanical data show that the envelope for the onset of shear‐enhanced compaction can be well approximated by an elliptical cap. The DVC analysis revealed the development of shear bands through the BDT, but no evidence of compaction bands. The shear band angles were between 29° and 46° with respect to the maximum principal stress. Compiling these new results with published data on Purbeck and Leitha limestones, we showed that inelastic compaction in each of these dual porosity allochemical limestones was in a good agreement with the normality condition, as defined in plasticity theory. Comparison of the observed failure modes with predictions based on bifurcation analysis showed that the shear band angles are consistently smaller than the theoretical predictions.
The Challenging Depths of Titan's Seas
Authors: Lorenz Ralph D.
Published: April 2021

New analyses of Cassini radar altimeter data (Poggiali et al., 2020, https://doi.org/10.1029/2020JE006558) measure the 85 m depth and “brackish” (moderately ethane‐poor) composition of Moray Sinus, an estuary at the northern margin of Titan's largest sea, Kraken Mare. No bottom echo was detected on Kraken itself, suggesting it is either very deep, ethane‐rich, or both.
Dynamics of Hyporheic Exchange Flux and Fine Particle Deposition Under Moving Bedforms
Authors: Teitelbaum Yoni , Dallmann Jonathan , Phillips Colin B. , Packman Aaron I. , Schumer Rina , Sund Nicole L. , Hansen Scott K. , Arnon Shai
Published: April 2021

Deposition of fine suspended particles can reduce hyporheic exchange flux (HEF), which may result in impairment of various ecological processes. However, the dynamics of fine particle deposition and streambed clogging are still not well understood, especially when the bed is in motion. We conducted flume experiments to study the effects of coupled sand‐clay dynamics on HEF with episodic (pulse) inputs of suspended kaolinite. Three experiments with a mobile sand bed and constant discharge were conducted with repeated injection of suspended kaolinite pulses at fixed concentration increments of 0.16, 0.41, and 0.66 g/L, respectively. HEF and participating porewater volume were assessed using tracer tests. Kaolinite deposition rates were inferred from turbidity measurements while deposition patterns were measured using core samples. We found that fine sediment primarily accumulated within a layer below the bedform scour zone, and that this layer was thicker when kaolinite was added in larger pulses. HEF declined linearly over time as kaolinite accumulated in the bed sediment; an increase of 0.1% kaolinite in the bed led to a decrease in HEF of 26.6 cm/day, regardless of the pulse concentration. However, the same kaolinite increase led to a reduction of 50% in participating pore volume for larger kaolinite pulses, versus only 30% for the smallest pulse. These results indicate that clogging occurs not just during and after high‐flow events, but also under constant flow conditions in which episodic deposition of suspended clay by HEF leads to the formation of a low‐conductivity layer in the bed.
Identifying More Realistic Model Structures by Electrical Conductivity Observations of the Karst Spring
Authors: Chang Yong , Hartmann Andreas , Liu Ling , Jiang Guanghui , Wu Jichun
Published: April 2021

Electrical conductivity (EC) of karst spring discharge has always been a fundamental variable to characterize karst systems. However, to incorporate EC into the lumped hydrologic modeling is challenging but has a huge potential since EC observations are widely collected. In this study, we present a new framework to integrate EC into lumped karst hydrological models for model structure identification and parameter uncertainty reduction. Our framework is tested in a small, well‐instrumented karst catchment near Guilin city (China) where EC dynamics are mostly controlled by the dissolution of carbonate rock and dilution by event water. Four karst models with different structures were equipped to consider the linear growth of EC with the carbonate rock dissolution and its mixing within the karst system. Applying a parameter estimation framework that accounts for uncertainty in discharge and EC simulations, we find that all hydrologic models obtain similar performances concerning spring discharge. However, their performances in simulating spring EC strongly differ permitting us to identify the most realistic model out of the four model structures. Our analysis further shows that including EC into parameter estimation reduces parameter uncertainty concerning concentrated flow in the conduits and helps to estimate immobile water storage in the system. Consequently, our new framework to include EC in karst models provides new directions for the more realistic simulation that can easily be transferred to other karst systems where EC dynamics are controlled by rock dissolution and dilution by event water.
Smooth muscle-specific HuR knockout induces defective autophagy and atherosclerosis
Authors: Liu Shanshan , Jiang Xiuxin , Cui Xiuru , Wang Jingjing , Liu Shangming , Li Hongxuan , Yang Jianmin , Zhang Cheng , Zhang Wencheng
Published: April 2021

Human antigen R (HuR) is a widespread RNA-binding protein involved in homeostatic regulation and pathological processes in many diseases. Atherosclerosis is the leading cause of cardiovascular disease and acute cardiovascular events. However, the role of HuR in atherosclerosis remains unknown. In this study, mice with smooth muscle-specific HuR knockout (HuRSMKO) were generated to investigate the role of HuR in atherosclerosis. HuR expression was reduced in atherosclerotic plaques. As compared with controls, HuRSMKO mice showed increased plaque burden in the atherosclerotic model. Mechanically, HuR could bind to the mRNAs of adenosine 5′-monophosphate-activated protein kinase (AMPK) α1 and AMPKα2, thus increasing their stability and translation. HuR deficiency reduced p-AMPK and LC3II levels and increased p62 level, thereby resulting in defective autophagy. Finally, pharmacological AMPK activation induced autophagy and suppressed atherosclerosis in HuRSMKO mice. Our findings suggest that smooth muscle HuR has a protective effect against atherosclerosis by increasing AMPK-mediated autophagy.
Cellular FLICE-like inhibitory protein (cFLIP) critically maintains apoptotic resistance in human lens epithelial cells
Authors: Huangfu Jingru , Hao Caili , Wei Zongbo , Wormstone I. Michael , Yan Hong , Fan Xingjun
Published: April 2021

The present study aims to understand the mechanism of the lens epithelial cell’s strong anti-apoptotic capacity and survival in the mature human lens that, on the one hand, maintains lens transparency over several decades, while on the other hand, increases the risk of posterior capsule opacification (PCO). Here we compared FHL124 cells and HeLa cells, spontaneously immortalized epithelial cell lines derived from the human lens and cervical cancer cells, respectively, of their resistance to TNFα-mediated cell death. TNFα plus cycloheximide (CHX) triggered almost all of HeLa cell death. FHL124 cells, however, were unaffected and able to block caspase-8 activation as well as prevent caspase-3 and PARP-1 cleavage. Interestingly, despite spontaneous NFκB and AP-1 activation and upregulation of multiple cell survival/anti-apoptotic genes in both cell types, only FHL124 cells were able to survive the TNFα challenge. After screening and comparing the cell survival genes, cFLIP was found to be highly expressed in FHL124 cells and substantially upregulated by TNFα stimulation. FHL124 cells with a mild cFLIP knockdown manifested a profound apoptotic response to TNFα stimulus similar to HeLa cells. Most importantly, we confirmed these findings in an ex vivo lens capsular bag culture system. In conclusion, our results show that cFLIP is a critical gene that is regulating lens epithelial cell survival.
A universal method to easily design tough and stretchable hydrogels
Authors: Norioka Chisa , Inamoto Yuino , Hajime Chika , Kawamura Akifumi , Miyata Takashi
Published: April 2021

Hydrogels are flexible materials that have high potential for use in various applications due to their unique properties. However, their applications are greatly restricted by the low mechanical performance caused by high water content and inhomogeneous networks. This paper reports a universal strategy for easily preparing hydrogels that are tough and stretchable without any special structures or complicated processes. Our strategy involves tuning the polymerization conditions to form networks with many polymer chain entanglements to achieve energy dissipation. Tough and stretchable hydrogels can be prepared by free radical polymerization with a high monomer concentration and low cross-linker content to optimize the balance between physical and chemical cross-links by entanglements and covalent bonds, respectively. The strategy of using polymer chain entanglements for energy dissipation allows us to overcome the limitation of low mechanical performance, which leads to the wide practical use of hydrogels.
Adenosine integrates light and sleep signalling for the regulation of circadian timing in mice
Authors: Jagannath Aarti , Varga Norbert , Dallmann Robert , Rando Gianpaolo , Gosselin Pauline , Ebrahimjee Farid , Taylor Lewis , Mosneagu Dragos , Stefaniak Jakub , Walsh Steven , Palumaa Teele , Di Pretoro Simona , Sanghani Harshmeena , Wakaf Zeinab , Churchill Grant C. , Galione Antony , Peirson Stuart N. , Boison Detlev , Brown Steven A. , Foster Russell G. , Vasudevan Sridhar R.
Published: April 2021

The accumulation of adenosine is strongly correlated with the need for sleep and the detection of sleep pressure is antagonised by caffeine. Caffeine also affects the circadian timing system directly and independently of sleep physiology, but how caffeine mediates these effects upon the circadian clock is unclear. Here we identify an adenosine-based regulatory mechanism that allows sleep and circadian processes to interact for the optimisation of sleep/wake timing in mice. Adenosine encodes sleep history and this signal modulates circadian entrainment by light. Pharmacological and genetic approaches demonstrate that adenosine acts upon the circadian clockwork via adenosine A1/A2A receptor signalling through the activation of the Ca2+ -ERK-AP-1 and CREB/CRTC1-CRE pathways to regulate the clock genes Per1 and Per2. We show that these signalling pathways converge upon and inhibit the same pathways activated by light. Thus, circadian entrainment by light is systematically modulated on a daily basis by sleep history. These findings contribute to our understanding of how adenosine integrates signalling from both light and sleep to regulate circadian timing in mice.
Six-fold increase of atmospheric pCO2 during the Permian–Triassic mass extinction
Authors: Wu Yuyang , Chu Daoliang , Tong Jinnan , Song Haijun , Dal Corso Jacopo , Wignall Paul B. , Song Huyue , Du Yong , Cui Ying
Published: April 2021

The Permian–Triassic mass extinction was marked by a massive release of carbon into the ocean-atmosphere system, evidenced by a sharp negative carbon isotope excursion. Large carbon emissions would have increased atmospheric pCO2 and caused global warming. However, the magnitude of pCO2 changes during the PTME has not yet been estimated. Here, we present a continuous pCO2 record across the PTME reconstructed from high-resolution δ13C of C3 plants from southwestern China. We show that pCO2 increased from 426 +133/−96 ppmv in the latest Permian to 2507 +4764/−1193 ppmv at the PTME within about 75 kyr, and that the reconstructed pCO2 significantly correlates with sea surface temperatures. Mass balance modelling suggests that volcanic CO2 is probably not the only trigger of the carbon cycle perturbation, and that large quantities of 13C-depleted carbon emission from organic matter and methane were likely required during complex interactions with the Siberian Traps volcanism.
Synthetic control over the binding configuration of luminescent sp3-defects in single-walled carbon nanotubes
Authors: Settele Simon , Berger Felix J. , Lindenthal Sebastian , Zhao Shen , El Yumin Abdurrahman Ali , Zorn Nicolas F. , Asyuda Andika , Zharnikov Michael , Högele Alexander , Zaumseil Jana
Published: April 2021

The controlled functionalization of single-walled carbon nanotubes with luminescent sp3-defects has created the potential to employ them as quantum-light sources in the near-infrared. For that, it is crucial to control their spectral diversity. The emission wavelength is determined by the binding configuration of the defects rather than the molecular structure of the attached groups. However, current functionalization methods produce a variety of binding configurations and thus emission wavelengths. We introduce a simple reaction protocol for the creation of only one type of luminescent defect in polymer-sorted (6,5) nanotubes, which is more red-shifted and exhibits longer photoluminescence lifetimes than the commonly obtained binding configurations. We demonstrate single-photon emission at room temperature and expand this functionalization to other polymer-wrapped nanotubes with emission further in the near-infrared. As the selectivity of the reaction with various aniline derivatives depends on the presence of an organic base we propose nucleophilic addition as the reaction mechanism.
SLPI is a critical mediator that controls PTH-induced bone formation
Authors: Morimoto Akito , Kikuta Junichi , Nishikawa Keizo , Sudo Takao , Uenaka Maki , Furuya Masayuki , Hasegawa Tetsuo , Hashimoto Kunihiko , Tsukazaki Hiroyuki , Seno Shigeto , Nakamura Akira , Okuzaki Daisuke , Sugihara Fuminori , Ninomiya Akinori , Yoshimura Takeshi , Takao-Kawabata Ryoko , Matsuda Hideo , Ishii Masaru
Published: April 2021

Osteoclastic bone resorption and osteoblastic bone formation/replenishment are closely coupled in bone metabolism. Anabolic parathyroid hormone (PTH), which is commonly used for treating osteoporosis, shifts the balance from osteoclastic to osteoblastic, although it is unclear how these cells are coordinately regulated by PTH. Here, we identify a serine protease inhibitor, secretory leukocyte protease inhibitor (SLPI), as a critical mediator that is involved in the PTH-mediated shift to the osteoblastic phase. Slpi is highly upregulated in osteoblasts by PTH, while genetic ablation of Slpi severely impairs PTH-induced bone formation. Slpi induction in osteoblasts enhances its differentiation, and increases osteoblast–osteoclast contact, thereby suppressing osteoclastic function. Intravital bone imaging reveals that the PTH-mediated association between osteoblasts and osteoclasts is disrupted in the absence of SLPI. Collectively, these results demonstrate that SLPI regulates the communication between osteoblasts and osteoclasts to promote PTH-induced bone anabolism.
Author Correction: Oil palm expansion and deforestation in Southwest Cameroon associated with proliferation of informal mills
Authors: Ordway Elsa M. , Naylor Rosamond L. , Nkongho Raymond N. , Lambin Eric F.
Published: April 2021

A Correction to this paper has been published: https://doi.org/10.1038/s41467-021-22418-3
Input-specific modulation of murine nucleus accumbens differentially regulates hedonic feeding
Authors: Christoffel Daniel J. , Walsh Jessica J. , Heifets Boris D. , Hoerbelt Paul , Neuner Sophie , Sun Gordon , Ravikumar Vinod K. , Wu Hemmings , Halpern Casey H. , Malenka Robert C.
Published: April 2021

Hedonic feeding is driven by the “pleasure” derived from consuming palatable food and occurs in the absence of metabolic need. It plays a critical role in the excessive feeding that underlies obesity. Compared to other pathological motivated behaviors, little is known about the neural circuit mechanisms mediating excessive hedonic feeding. Here, we show that modulation of prefrontal cortex (PFC) and anterior paraventricular thalamus (aPVT) excitatory inputs to the nucleus accumbens (NAc), a key node of reward circuitry, has opposing effects on high fat intake in mice. Prolonged high fat intake leads to input- and cell type-specific changes in synaptic strength. Modifying synaptic strength via plasticity protocols, either in an input-specific optogenetic or non-specific electrical manner, causes sustained changes in high fat intake. These results demonstrate that input-specific NAc circuit adaptations occur with repeated exposure to a potent natural reward and suggest that neuromodulatory interventions may be therapeutically useful for individuals with pathologic hedonic feeding.
Simultaneous tuning of the magnetic anisotropy and thermal stability of $$\alpha ^{''}$$-phase Fe$$_{16}$$N$$_{2}$$
Authors: Odkhuu D. , Hong S. C.
Published: April 2021

Simultaneously enhancing the uniaxial magnetic anisotropy ($$K_u$$

K
u

) and thermal stability of $$\alpha ^{''}$$

α

′
′

-phase Fe$$_{16}$$

16

N$$_{2}$$

2

without inclusion of heavy-metal or rare-earth (RE) elements has been a challenge over the years. Herein, through first-principles calculations and rigid-band analysis, significant enhancement of $$K_u$$

K
u

is proposed to be achievable through excess valence electrons in the Fe$$_{16}$$

16

N$$_{2}$$

2

unit cell. We demonstrate a persistent increase in $$K_u$$

K
u

up to 1.8 MJ m$$^{\text {-}3}$$

-
3

, a value three times that of 0.6 MJ m$$^{\text {-}3}$$

-
3

in $$\alpha ^{''}$$

α

′
′

-Fe$$_{16}$$

16

N$$_{2}$$

2

, by simply replacing Fe with metal elements with more valence electrons (Co to Ga in the periodic table). A similar rigid-band argument is further adopted to reveal an extremely large $$K_u$$

K
u

up to 2.4 MJ m$$^{\text {-}3}$$

-
3

in (Fe$$_{0.5}$$

0.5

Co$$_{0.5}$$

0.5

)$$_{16}$$

16

N$$_{2}$$

2

obtained by replacing Co with Ni to Ga. Such a strong $$K_u$$

K
u

can also be achieved with the replacement by Al, which is isoelectronic to Ga, with simultaneous improvement of the phase stability. These results provide an instructive guideline for simultaneous manipulation of $$K_u$$

K
u

and the thermal stability in 3d-only metals for RE-free permanent magnet applications.
Author Correction: Feasibility, safety and accuracy of a CT-guided robotic assistance for percutaneous needle placement in a swine liver model
Authors: Guiu Boris , De Baère Thierry , Noel Guillaume , Ronot Maxime
Published: April 2021

An amendment to this paper has been published and can be accessed via a link at the top of the paper.