bluuebunny/crossref_metadata_2025 huggingface dataset:
Resveratrol oligomer structure in Dipterocarpaceaeous plants
Authors: Ito Tetsuro
Published: April 2020

Oligostilbenoids are a group of natural products derived from the oxidative coupling of C6–C2–C6 units found in some plant families. A structurally diverse chemical pool is produced after the successive regioselective and stereoselective oligomerization of resveratrol. This review describes the current status and knowledge of the structure of resveratrol oligomers (ROs) in Dipterocarpaceaeous plants (DPs). Beginning with the recently validated formation of ROs in DPs, each downstream conversion is described from the perspective of the resveratrol coupling mode. Particular emphasis is placed upon the regioselectivity of monomer- and dimer-derived radical–radical coupling processes, which are responsible for producing dimers, trimers, and tetramers with various cyclic frame skeletons, as well as related processes that result in highly condensed scaffolds, such as hexamers and octamers. Trimers in oxidized, dearomatized, and rearranged forms are also summarized, as well as the biogenic relationship between the compounds. Furthermore, emphasis is placed on the O- and C-glucosides of ROs, as well as on the hetero-coupled ROs. In addition, several stereoisomers that originate from asymmetric carbons and the stereochemistry with respect to the conformation due to the chiral axis are described. Besides, NMR spectroscopic properties such as coalescence and anisotropy are briefly described. Approaches to determine absolute configuration are also summarized.
Inverse distance weighting method optimization in the process of digital terrain model creation based on data collected from a multibeam echosounder
Authors: Maleika Wojciech
Published: April 2020

This paper presents the optimization of the inverse distance weighting method (IDW) in the process of creating a digital terrain model (DTM) of the seabed based on bathymetric data collected using a multibeam echosounder (MBES). There are many different methods for processing irregular measurement data into a grid-based DTM, and the most popular of these methods are inverse distance weighting (IDW), nearest neighbour (NN), moving average (MA) and kriging (K). Kriging is often considered one of the best methods in interpolation of heterogeneous spatial data, but its use is burdened by a significantly long calculation time. In contrast, the MA method is the fastest, but the calculated models are less accurate. Between them is the IDW method, which gives satisfactory accuracy with a reasonable calculation time. In this study, the author optimized the IDW method used in the process of creating a DTM seabed based on measurement points from MBES. The goal of this optimization was to significantly accelerate the calculations, with a possible additional increase in the accuracy of the created model. Several variants of IDW methods were analysed (dependent on the search radius, number of points in the interpolation, power of the interpolation and applied smoothing method). Finally, the author proposed an optimization of the IDW method, which uses a new technique of choosing the nearest points during the interpolation process (named the growing radius). The experiments presented in the paper and the results obtained show the true potential of the IDW optimized method in the case of DTM estimation.
Precipitation–soil water chemistry relationship: case study of an intensively managed grassland ecosystem in southwest England
Authors: Eludoyin Adebayo Oluwole
Published: April 2020

Environmental assessments typically require fine- or high-resolution datasets, example of which the Environmental Change Network (ECN) provides. This study has therefore taken advantage of the free access to the datasets to investigate temporal characteristics of precipitation and soil water chemistry, and relationship between the concentration of selected chemical variables in precipitation and soil water at 0–10 cm and below 10 cm depths based on data availability. The aim was to determine whether observations from the ECN data support results from the previous hypothesis on dominant run-off mechanism at the study area. Method of analysis involves inferential statistics and wavelet transform plot of selected physico-chemical variables for six (2010–2016) years. Results showed that most of the selected chemical variables exhibited low coefficient of determination in the relationship of their concentration in precipitation and soil water. Relatively linear relationships, however, occurred in the values of conductivity, Cl−, Ca2+, alkalinity and Mg2+ between the 0–10 cm and below 10 cm depths, indicating mixing of soil water at both soil zones. Inference from the results suggests a possible significant role of pre-event water or geological influence on soil water chemistry. The study affirms the hypothesis that saturation overland flow dominates areas underlain by Halstow soil series in the area.
Non-enzymatic covalent modifications: a new link between metabolism and epigenetics
Authors: Zheng Qingfei , Maksimovic Igor , Upad Akhil , David Yael
Published: April 2020

Epigenetic modifications, including those on DNA and histones, have been shown to regulate cellular metabolism by controlling expression of enzymes involved in the corresponding metabolic pathways. In turn, metabolic flux influences epigenetic regulation by affecting the biosynthetic balance of enzyme cofactors or donors for certain chromatin modifications. Recently, non-enzymatic covalent modifications (NECMs) by chemically reactive metabolites have been reported to manipulate chromatin architecture and gene transcription through multiple mechanisms. Here, we summarize these recent advances in the identification and characterization of NECMs on nucleic acids, histones, and transcription factors, providing an additional mechanistic link between metabolism and epigenetics.
Social Justice Games: Building an Escape Room on Elder Abuse through Participatory Action Research
Authors: Lafontaine Constance , Sawchuk Kim , DeJong Scott
Published: April 2020

This paper discusses the creation of an escape room on older adult mistreatment (or elder abuse). The game, titled Sandra's Keys, invited players to engage with the story of a fictional older woman dealing with a situation of abuse through a series puzzles. The escape room sought to bring players into a conversation about the different forms of elder abuse, and to give them a greater understanding of their role as bystanders and of the potential ways to intervene. The escape room game was co-designed by researchers, a group of older adults activists in Montreal and a social worker. This paper focuses on how we made this game and the methodological principles and values behind the design process. This design process is grounded in Participatory Action Research and is inspired by the writings of radical theatre activist Augusto Boal. One of its aims was to consolidate long standing relationships between the members of the design team around a common social justice goal. We map out the potential of games to become tools in the ‘arsenal’ of community-based activism and to playfully contradict dominant societal norms related to age. Finally, we introduce the term ‘social justice game’ to assert the connections between activism, social justice and games studies.
Making and Receiving Offers of Help on Social Media Following Disaster Predict Posttraumatic Growth but not Posttraumatic Stress
Authors: Levaot Yael , Greene Talya , Palgi Yuval
Published: April 2020

Objectives:

Social media provides an opportunity to engage in social contact and to give and receive help by means of online social networks. Social support following trauma exposure, even in a virtual community, may reduce feelings of helplessness and isolation, and, therefore, reduce posttraumatic stress symptoms (PTS), and increase posttraumatic growth (PTG). The current study aimed to assess whether giving and/or receiving offers of help by means of social media following large community fires predicted PTS and/or PTG.

Methods:

A convenience sample of 212 adults living in communities that were affected by large-scale community fires in Israel (November 2016) completed questionnaires on giving and receiving offers of help by means of social media within 1 mo of the fire (W1), and the PTSD checklist for DSM-5 (PCL-5) and PTG questionnaire (PTGI-SF), 4 mo after the fire (W2).

Results:

Regression analyses showed that, after controlling for age, gender, and distance from fire, offering help by means of social media predicted higher PTG (β = 0.22; t = 3.18; P < 0.01), as did receiving offers of help by means of social media (β = 0.18; t = 2.64; P < 0.01). There were no significant associations between giving and/or receiving offers of help and PTS.

Conclusions:

Connecting people to social media networks may help in promoting posttraumatic growth, although might not impact on posttraumatic symptoms. This is one of the first studies to highlight empirically the advantages of social media in the aftermath of trauma exposure.
The Ontogenetic Foundations of Epistemic Norms
Authors: Tomasello Michael
Published: April 2020

In this paper, I approach epistemic norms from an ontogenetic point of view. I argue and present evidence that to understand epistemic norms – e.g., scientific norms of methodology and the evaluation of evidence – children must first develop through their social interactions with others three key concepts. First is the concept of belief, which provides the most basic distinction on which scientific investigations rest: the distinction between individual subjective perspectives and an objective reality. Second is the concept of reason, which in the context of science obligates practitioners to justify their claims to others with reasons by grounding them in beliefs that are universally shared within the community. Third is the concept of social norm, which is not primarily epistemic, but provides children with an understanding of norms as collective agreements. The theoretical argument is that all three of these concepts emerge not from just any kind of social interaction, but specifically from social interactions structured by the human species’ unique capacities for shared intentionality.
Onset and maturation of Asian summer monsoon precipitation reconstructed from intra-annual tree-ring oxygen isotopes from the southeastern Tibetan Plateau
Authors: Xu Chenxi , Zhu Haifeng , Wang S.-Y. Simon , Shi Feng , An Wenling , Li Zhen , Sano Masaki , Nakatsuka Takeshi , Guo Zhengtang
Published: April 2020

We present a long-term seasonal tree ring cellulose oxygen isotope (δ18Oc) time series created by analyzing four segments (S1, S2, S3, and S4) per year during the period of 1951–2009 from southeastern Tibetan Plateau. This intraseasonal δ18Ocreveals the onset and mature phase of the summer monsoon precipitation in this region. Analysis indicates that the δ18Ocof S1 has the strongest correlation with precipitation during the regional monsoon onset (29–33 pentads, May 21–June 10,r= −0.69), and the δ18Ocvalues for S2, S3, and S4 correlate strongly with June, July, and August precipitation, respectively. Combined δ18Ocof S2, S3, and S4 shows the most robust correlation (r= −0.82) with the mature-phase monsoon precipitation (June-July-August, JJA), passing rigorous statistical tests for calibration and verification in dendroclimatology. These results demonstrate the feasibility in using long-term intraseasonal δ18Octo reconstruct the Asian summer monsoon's intraseasonal variations.
Profit and Patrimony: Property, Markets, and Public Debt in Late Medieval Genoa
Authors: Miner Jeffrey
Published: April 2020

Scholars have long linked medieval and early modern public debts to the rise of capitalism. This article considers one prominent case study in the development of permanent public debt: late medieval Genoa. Previous scholarship has focused on financial speculation and markets for shares as central to how public debts functioned. However, by considering complementary types of sources, this article demonstrates that inheritance strategies and patrimonial considerations operated in dialogue with markets in the development of urban public debts, both in Genoa and elsewhere in Europe.
Premodern European Capitalism, Christianity, and Florence
Authors: Caferro William
Published: April 2020

The essay examines the role of Christianity in premodern European capitalism, with regard to the city of Florence. It traces the formation of the historical construct and the influence of Werner Sombart's Der moderne Kapitalismus, a work much neglected nowadays in the Anglophone academy. The article seeks to historicize and contextualize faith and economy, to stress their fundamentally intertwined nature and more specifically how notions of “negotiation” and diriturra (moral Christian rectitude) connect the seemingly antagonistic sides, and connect also Florentine finance and business history, which are too often studied independently. It argues that Christian rectitude and service to the church (a noncynical quid pro quo) were conjoined with a calculated, reasoned profit motive--evident especially among papal bankers, a key sector of the Florentine economy.
Big Business for Firms and States: Silk Manufacturing in Renaissance Italy
Authors: Franceschi Franco
Published: April 2020

Silk manufacturing began in Lucca in the twelfth century and by the fifteenth century Italy had become the largest producer of silk textiles in Europe, nurtured by extensive domestic and foreign demand for the luxurious fabric. This essay explores the market for silk textiles, the organization of the silk industry, and the role played in it by guilds, entrepreneurs and their capital, and highly sought after artisans. Just as silk manufacturing was an important and lucrative business for entrepreneurs, this article argues, so was it a crucial strategic activity for the governments of Italy's Renaissance states, whose incentives, protections, and investments helped to start up and grow the sector with the aim of generating wealth and strengthening their respective economies.
THE CORPORATE AGENT IN CRIMINAL LAW – AN ARGUMENT FOR COMPREHENSIVE IDENTIFICATION
Authors: Dsouza Mark
Published: April 2020

We use doctrines of identification to explain how corporations may commit criminal offences in their own right, but current versions thereof have several shortcomings. Here, I suggest that reformulating the identification doctrine to treat all corporate officers and employees as embodying the corporation when acting within their real or ostensible authority, might remedy these shortcomings. Arguments against the resulting expansion of corporate criminal liability are unconvincing, especially when juxtaposed with the criminal law's response to similar arguments made on behalf of natural persons. This may indicate that we should also moderate the criminal law's harshness towards natural persons.
How is the moral stance related to the intentional stance and group thinking?
Authors: Rakoczy Hannes
Published: April 2020

The natural history of our moral stance told here in this commentary reveals the close nexus of morality and basic social-cognitive capacities. Big mysteries about morality thus transform into smaller and more manageable ones. Here, I raise questions regarding the conceptual, ontogenetic, and evolutionary relations of the moral stance to the intentional and group stances and to shared intentionality.
Psychological consequences of the normativity of moral obligation
Authors: Darwall Stephen
Published: April 2020

An adequate moral psychology of obligation must bear in mind that although the “sense of obligation” is psychological, what it is a sense of, moral obligation itself, is not. It is irreducibly normative. I argue, therefore, that the “we” whose demands the sense of obligation presupposes must be an ideal rather than an actual “we.”
Obligation at zero acquaintance
Authors: Dunning David , Fetchenhauer Detlef , Schlösser Thomas
Published: April 2020

Social obligation begins far before people establish explicit cooperative relationships. Research on trust suggests that people feel obligated to trust other people even at zero acquaintance, thus trusting complete strangers even though they privately expect to be exploited. Such obligations promote mutually beneficial behavior among strangers and likely help people build goodwill needed for more long-lasting relationships.
Who are “we”? Dealing with conflicting moral obligations
Authors: Shaw Alex , Choshen-Hillel Shoham
Published: April 2020

Satisfying one's obligations is an important part of being human. However, people's obligations can often prescribe contradictory behaviors. Moral obligations conflict (loyalty vs. fairness), and so do obligations to different groups (country vs. family when one is called to war). We propose that a broader framework is needed to account for how people balance different social and moral obligations.
Toleration and Some Related Concepts in Kant
Authors: Bain Andrew , Formosa Paul
Published: April 2020

In this article we examine Kant’s understanding of toleration by including a study of all instances in which he directly uses the language of toleration and related concepts. We use this study to resolve several key areas of interpretative dispute concerning Kant’s views on toleration. We argue that Kant offers a nuanced and largely unappreciated approach to thinking about toleration, and related concepts, across three normative spheres: the political, the interpersonal and the personal. We examine shortcomings in earlier interpretations and conclude by arguing that the theme of toleration in Kant’s work, while coherent and important, is neither as central nor as peripheral as suggested by previous interpretations. Further, while Kant is critical of the arrogance of toleration in the political sphere, he is more positive toward the role of toleration in the interpersonal and personal spheres since it promotes virtue.
Kant’s Doctrine of the Highest Good: A Theologico-Political Interpretation
Authors: Brown Étienne
Published: April 2020

Kant’s discussion of the highest good is subject to continuous disagreement between the proponents of two interpretations of this concept. According to the secular interpretation, Kant conceived of the highest good as a political ideal which can be realized through human agency alone, albeit only from theCritique of the Power of Judgementonwards. By way of contrast, proponents of the theological interpretation find Kant’s treatment of the highest good in his later works to be wholly coherent with the discussions of this concept found in the secondCritique. In their view, however, Kant never conceived of the highest good as a political ideal, and some go as far as to argue that it is the work of God alone. In this article, I defend a theologico-political account of the highest good that avoids the pitfalls of both readings.
The Possibility Proof is Not What Remains from Kant'sBeweisgrund
Authors: Oberst Michael
Published: April 2020

The so-called ‘possibility proof’ in Kant's pre-CriticalBeweisgrundhas been widely discussed in the literature, and it is a common view that he never really abandoned it. As I shall argue, this reading is mistaken. I aim to show that the natural illusion in theCritique of Pure Reason, which is usually taken to be the possibility proof turned into a transcendental illusion, has both a different conclusion and a different argument than the possibility proof. Rather, what remains fromBeweisgrundis what I will call the ‘proofa posteriori’, which theCritiqueturns into a transcendental illusion that is of regulative use for reason.
The rationale for MR-only delineation and planning: retrospective CT–MR registration and target volume analysis for prostate radiotherapy
Authors: Ilamurugu Arivarasan , Chandrasekaran Anu Radha
Published: April 2020

Aim:

Magnetic resonance imaging (MRI) is indispensable for treatment planning in prostate radiotherapy (PR). Registration of MRI when compared to planning CT (pCT) is prone to uncertainty and this is rarely reported. In this study, we have compared three different types of registration methods to justify the direct use of MRI in PR.

Methods and materials:

Thirty patients treated for PR were retrospectively selected for this study and all underwent both CT and MRI. The MR scans were registered to the pCT using markers, focused and unfocussed methods and their registration are REGM, REGF, and REGNF, respectively. Registration comparison is done using the translational differences of three axes from the centre-of-mass values of gross tumour volume (GTV) generated using MRI.

Results:

The average difference in all three axes (x, y, z) is (1, 2·5, 2·3 mm) and (1, 3, 2·3 mm) for REGF-REFNF and REGF-REGM, respectively. MR-based GTV Volume is less in comparison to CT-based GTV and it is significantly different (p < 0·001).

Findings:

Image registration uncertainty is unavoidable for a regular CT–MR workflow. Additional planning target volume margin ranging from 2 to 3mm could be avoided if MR-only workflow is employed. This reduction in the margin is beneficial for small tumours treated with hypofractionation.
Association between early weight gain and later adiposity in Sri Lankan adolescents
Authors: Samaranayake D. , Lanerolle P. , Waidyatilaka I. , de Lanerolle-Dias M. , Hills A. P. , Wickremasinghe A. R. , Wickramasinghe V. P.
Published: April 2020

Early growth pattern is increasingly recognized as a determinant of later obesity. This study aimed to identify the association between weight gain in early life and anthropometry, adiposity, leptin, and fasting insulin levels in adolescence. A cross-sectional study was conducted in 366 school children aged 11–13 years. Weight, height, and waist circumference (WC) were measured. Fat mass (FM) was assessed using bioelectrical impedance analysis. Blood was drawn after a 12-h fast for insulin and leptin assay. Birth weight and weight at 6 months and at 18 months were extracted from Child Health Development Records. An increase in weight SD score (SDS) by ≥0.67 was defined as accelerated weight gain. Linear mixed-effects modeling was used to predict anthropometry, adiposity, and metabolic outcomes using sex, pubertal status, accelerated weight gain as fixed factors; age, birth weight, and family income as fixed covariates, and school as a random factor. Children with accelerated weight gain between birth and 18 months had significantly higher body mass index (BMI) SDS, WC SDS, height SDS, %FM, fat mass index (FMI), fat free mass index (FFMI), and serum leptin levels in adolescence. Accelerated weight gain between 6 and 18 months was associated with higher BMI SDS, WC SDS, %FM, and FMI, but not with height SDS or FFMI. Accelerated weight gain at 0–6 months, in children with low birth weight, was associated with higher height SDS, BMI SDS, WC SDS, %FM, and FMI; in children with normal birth weight, it was associated with BMI SDS, WC SDS, height SDS, and FFMI, but not with %FM or FMI. Effects of accelerated weight gain in early life on anthropometry and adiposity in adolescence varied in different growth windows. Accelerated weight gain during 6–18 months was associated with higher FM rather than linear growth. Effects of accelerated weight gain between 0 and 6 months varied with birth weight.
Differential Effects of Competence and Morality on Self-Esteem at the	Individual and the Collective Level
Authors: Soral Wiktor , Kofta Mirosław
Published: April 2020

Abstract. The importance of various trait dimensions explaining positive global self-esteem has been the subject of numerous studies. While some have provided support for the importance of agency, others have highlighted the importance of communion. This discrepancy can be explained, if one takes into account that people define and value their self both in individual and in collective terms. Two studies ( N = 367 and N = 263) examined the extent to which competence (an aspect of agency), morality, and sociability (the aspects of communion) promote high self-esteem at the individual and the collective level. In both studies, competence was the strongest predictor of self-esteem at the individual level, whereas morality was the strongest predictor of self-esteem at the collective level.
Interaction of Cold Streaming Protons with the Reconnection Process
Authors: Tenfjord P. , Hesse M. , Norgren C. , Spinnangr S. F. , Kolstø H. , Kwagala N.
Published: April 2020

We employ a 2.5D particle‐in‐cell simulation to study a scenario where the reconnection process captures cold streaming protons. As soon as the tailward streaming protons become involved, they contribute to the overall momentum balance, altering the initially symmetric dynamics. Adding tailward‐directed momentum to the reconnection process results in a tailward propagation of the reconnection site. We investigate how the reconnection process reorganizes itself due to the changing momentum conditions on the kinetic scale and how the reconnection rate is affected. We find that adding tailward momentum does not result in a significantly different reconnection rate compared to the case without cold streaming protons, when scaled to the total Alfvén velocity. This implies that the effect of changing inflow conditions due to the motion of the reconnection site appears to be minimal. The dynamics of the particles are, however, significantly different depending on whether they enter on the tailward or Earthward side of the reconnection site. On the Earthward side they are reflected and thermalized, while on the tailward side they are picked up and accelerated. The cold proton density and Ez on the Earthward side are turbulent, while the tailward side has laminar cold proton density striations and an embedded Ez layer. Also, since the initial plasma sheet population is swept up on one side and flushed out on the other, asymmetries in the densities and strength of Hall fields emerge. Our results are important for understanding the development and dynamics of magnetospheric substorms and storms.
Lateral Variations in Thermochemical Structure of the Eastern Canadian Shield
Authors: Eeken Thomas , Goes Saskia , Petrescu Laura , Altoe Isabella
Published: April 2020

The origin of 3‐D seismic heterogeneity in Precambrian lithosphere has been enigmatic, because temperature variations in old stable shields are expected to be small and seismic sensitivity to major‐element compositional variations is limited. Previous studies indicate that metasomatic alteration may significantly affect average 1‐D structure below shields. Here, we perform a grid search for 3‐D thermochemical structure, including variations in alteration, to model published Rayleigh wave phase velocities between 20 and 160 s for the eastern part of the Archean Superior and Canadian Proterozoic Grenville Provinces. We find that, consistent with constraints from surface heat flow and xenoliths, the lithosphere is coolest (Moho heat flow 12–17 mW/m2) and the thermal boundary layer thickest (>250 km) in the northeastern Superior and warmest in the southeastern Grenville (Moho heat flow 20–25 mW/m2, thermal boundary thickness 160–200 km). Compositionally, the phase velocities for most of the Superior within our study region require little alteration, but in a few regions, fast velocities need to overlie slower velocities. These can be modeled with an eclogite layer in the midlithosphere, consistent with active seismic and xenolith evidence for remnants of subducted Archean crust. The phase velocities from the Grenville Province require significant metasomatic modification to explain the relatively low velocities of the shallow lithosphere, and the required intensity of alteration is highest in parts of the Grenville associated with arc accretion. Thus, the composition of the northeastern Canadian Shield appears to reflect different stages and styles of craton assembly.
Ring‐Moat Dome Structures (RMDSs) in the Lunar Maria: Statistical, Compositional, and Morphological Characterization and Assessment of Theories of Origin
Authors: Zhang Feng , Head James W. , Wöhler Christian , Bugiolacchi Roberto , Wilson Lionel , Basilevsky Alexander T. , Grumpe Arne , Zou Yong L.
Published: April 2020

Ring‐moat dome structures (RMDSs) are positive morphologic features found clustered across many mare regions on the Moon, of which only a few isolated examples have been previously reported. Our continuing survey has expanded the known locations of the RMDSs from ~2,600 to over 8,000, indicating that RMDSs are more common geological features than previously thought. This work presents a detailed geomorphological analysis of 532 RMDSs identified in several mare basins. The combination of detailed elemental mapping, morphological and morphometric analyses, spatial distribution relationships with other geologic structures, and comparison with terrestrial analogs lead us to conclude that (1) RMDSs represent low circular mounds with diameters of a few hundred meters (average about 200 m) and a mean height of 3.5 m. The mounds are surrounded by moats ranging from tens to over 100 m in width and up to several meters in depth; (2) there is a wide variation of titanium abundances, although RMDSs are more commonly found in mare regions of moderate‐to‐high titanium content (>3 wt% TiO2); (3) RMDSs are found to occur on or around fractures, graben, and volcanic edifices (small shields and cones); (4) a spatial association between RMDSs and Irregular Mare Patches (see Braden et al., 2014, https://doi.org/10.1038/ngeo2252) is observed, suggesting that both may form from related lava flows; (5) comparisons between RMDSs and lava inflationary structures on Earth support an inflation‐related extrusive nature and a genetic relationship with host lava flow processes; and (6) RMDS embayment relationships with craters of different degradation ages superposed on the host mare, and regolith development models, produces conflicting age relationships and divide theories of RMDS origin into two categories, (1) synchronous with the emplacement and cooling of the host lava flows ~3–4 Ga and (2) emplaced substantially after the host mare lava unit, in the period ~0–3 Ga. We outline the evidence supporting this age conundrum and implications for the different theories of origin and describe future research avenues to help resolve these outstanding questions.
Weak Magnetic Fields in the Outer Solar Nebula Recorded in CR Chondrites
Authors: Fu Roger R. , Kehayias Pauli , Weiss Benjamin P. , Schrader Devin L. , Bai Xue‐Ning , Simon Jacob B.
Published: April 2020

Theoretical investigations suggest that magnetic fields may have played an important role in driving rapid stellar accretion rates and efficient planet formation in protoplanetary disks. Experimental constraints on magnetic field strengths throughout the solar nebula can test the occurrence of magnetically driven disk accretion and the effect of magnetic fields on planetary accretion. Here we conduct paleomagnetic experiments on chondrule samples from primitive CR (Renazzo type) chondrites GRA 95229 and LAP 02342, which likely originated in the outer solar system between 3 and 7 AU approximately 3.7 million years after calcium aluminum‐rich inclusion formation. By extracting and analyzing 18 chondrule subsamples that contain primary, igneous ferromagnetic minerals, we show that CR chondrules carry internally non‐unidirectional magnetization that requires formation in a nebular magnetic field of ≤8.0 ± 4.3 μT (2σ). These weak magnetic fields may be due to the secular decay of nebular magnetic fields by 3.7 million years after calcium aluminum‐rich inclusions, spatial heterogeneities in the nebular magnetic field, or a combination of both effects. The possible inferred existence of spatial variations in the nebular magnetic field would be consistent with a prominent role for disk magnetism in the formation of density structures leading to gaps and planet formation.
Analytical Model for the Tidal Evolution of the Evection Resonance and the Timing of Resonance Escape
Authors: Ward William R. , Canup Robin M. , Rufu Raluca
Published: April 2020

A high‐angular momentum giant impact with the Earth can produce a Moon with a silicate isotopic composition nearly identical to that of Earth's mantle, consistent with observations of terrestrial and lunar rocks. However, such an event requires subsequent angular momentum removal for consistency with the current Earth‐Moon system. The early Moon may have been captured into the evection resonance, occurring when the lunar perigee precession period equals 1 year. It has been proposed that after a high‐angular momentum giant impact, evection removed the angular momentum excess from the Earth‐Moon pair and transferred it to Earth's orbit about the Sun. However, prior N‐body integrations suggest this result depends on the tidal model and chosen tidal parameters. Here, we examine the Moon's encounter with evection using a complementary analytic description and the Mignard tidal model. While the Moon is in resonance, the lunar longitude of perigee librates, and if tidal evolution excites the libration amplitude sufficiently, escape from resonance occurs. The angular momentum drain produced by formal evection depends on how long the resonance is maintained. We estimate that resonant escape occurs early, leading to only a small reduction (~ few to 10%) in the Earth‐Moon system angular momentum. Moon formation from a high‐angular momentum impact would then require other angular momentum removal mechanisms beyond standard libration in evection, as have been suggested previously.
Tear, Don’t Cut, to Reduce Microplastics
Authors: Kornei Katherine
Published: April 2020

Laboratory experiments reveal the numbers and types of microplastics produced by tearing, scissoring, and cutting everyday items.
Source‐Receiver Interferometric Redatuming Using Sparse Buried Receivers to Address Complex Near‐Surface Environments: A Case Study of Seismic Imaging Quality and Time‐Lapse Repeatability
Authors: Zhao Yang , Niu Fenglin , Liu Hongwei , Jia Xueyi , Yang Jidong , Huo Shoudong
Published: April 2020

Deploying sparse sources and receivers in a complex near‐surface environment for seismic imaging and monitoring remains a challenge. Complicated near‐surface structures with strong lateral velocity variations and thick weathering layers distort seismic wave paths and produce strong reverberations and scattering. Consequently, acquisition with a buried receiver system below the weathering layer is preferred for land surveys, but the cost of this approach is excessively high in real applications. To mitigate this problem, we propose a source‐receiver interferometry‐based redatuming method that can generate redatumed data beneath the near surface with a reduced cost. The new acquisition geometry consists of dense surface and sparse buried receivers. The workflow based on source‐receiver redatuming combines surface and buried systems by cross correlating direct waves recorded by buried receivers with the corresponding reflected waves recorded by surface receivers. The approach transforms surface source‐receiver records into virtually buried source‐receiver records. We effectively suppress the acquisition noises associated with the near‐surface structures because the proposed technique generates redatumed data below the weathering layer. We apply dip‐guided interpolation to the redatumed data to make the geometry consistent with the original surface geometry. The resulting records not only improve the seismic image quality and repeatability compared with the original records but also have a lower cost than a denseburied acquisition system. We use 13 seismic surveys carried out at different times to demonstrate the feasibility and advantage of the proposed method.
Nesfatin-1 decreases the motivational and rewarding value of food
Authors: Dore Riccardo , Krotenko Regina , Reising Jan Philipp , Murru Luca , Sundaram Sivaraj Mohana , Di Spiezio Alessandro , Müller-Fielitz Helge , Schwaninger Markus , Jöhren Olaf , Mittag Jens , Passafaro Maria , Shanabrough Marya , Horvath Tamas L. , Schulz Carla , Lehnert Hendrik
Published: April 2020

Homeostatic and hedonic pathways distinctly interact to control food intake. Dysregulations of circuitries controlling hedonic feeding may disrupt homeostatic mechanisms and lead to eating disorders. The anorexigenic peptides nucleobindin-2 (NUCB2)/nesfatin-1 may be involved in the interaction of these pathways. The endogenous levels of this peptide are regulated by the feeding state, with reduced levels following fasting and normalized by refeeding. The fasting state is associated with biochemical and behavioral adaptations ultimately leading to enhanced sensitization of reward circuitries towards food reward. Although NUCB2/nesfatin-1 is expressed in reward-related brain areas, its role in regulating motivation and preference for nutrients has not yet been investigated. We here report that both dopamine and GABA neurons express NUCB2/nesfatin-1 in the VTA. Ex vivo electrophysiological recordings show that nesfatin-1 hyperpolarizes dopamine, but not GABA, neurons of the VTA by inducing an outward potassium current. In vivo, central administration of nesfatin-1 reduces motivation for food reward in a high-effort condition, sucrose intake and preference. We next adopted a 2-bottle choice procedure, whereby the reward value of sucrose was compared with that of a reference stimulus (sucralose + optogenetic stimulation of VTA dopamine neurons) and found that nesfatin-1 fully abolishes the fasting-induced increase in the reward value of sucrose. These findings indicate that nesfatin-1 reduces energy intake by negatively modulating dopaminergic neuron activity and, in turn, hedonic aspects of food intake. Since nesfatin-1´s actions are preserved in conditions of leptin resistance, the present findings render the NUCB2/nesfatin-1 system an appealing target for the development of novel therapeutical treatments towards obesity.
Oleoylethanolamide decreases frustration stress-induced binge-like eating in female rats: a novel potential treatment for binge eating disorder
Authors: Romano Adele , Micioni Di Bonaventura Maria Vittoria , Gallelli Cristina Anna , Koczwara Justyna Barbara , Smeets Dorien , Giusepponi Maria Elena , De Ceglia Marialuisa , Friuli Marzia , Micioni Di Bonaventura Emanuela , Scuderi Caterina , Vitalone Annabella , Tramutola Antonella , Altieri Fabio , Lutz Thomas A. , Giudetti Anna Maria , Cassano Tommaso , Cifani Carlo , Gaetani Silvana
Published: April 2020

Binge eating disorder (BED) is the most frequent eating disorder, for which current pharmacotherapies show poor response rates and safety concerns, thus highlighting the need for novel treatment options. The lipid-derived messenger oleoylethanolamide (OEA) acts as a satiety signal inhibiting food intake through the involvement of central noradrenergic and oxytocinergic neurons. We investigated the anti-binge effects of OEA in a rat model of binge-like eating, in which, after cycles of intermittent food restrictions/refeeding and palatable food consumptions, female rats show a binge-like intake of palatable food, following a 15-min exposure to their sight and smell (“frustration stress”). Systemically administered OEA dose-dependently (2.5, 5, and 10 mg kg−1) prevented binge-like eating. This behavioral effect was associated with a decreased activation (measured by mapping the expression of c-fos, an early gene widely used as a marker of cellular activation) of brain areas responding to stress (such as the nucleus accumbens and amygdala) and to a stimulation of areas involved in the control of food intake, such as the VTA and the PVN. These effects were paralleled, also, to the modulation of monoamine transmission in key brain areas involved in both homeostatic and hedonic control of eating. In particular, a decreased dopaminergic response to stress was observed by measuring dopamine extracellular concentrations in microdialysates from the nucleus accumbens shell, whereas an increased serotonergic and noradrenergic tone was detected in tissue homogenates of selected brain areas. Finally, a decrease in corticotropin-releasing factor (CRF) mRNA levels was induced by OEA in the central amygdala, while an increase in oxytocin mRNA levels was induced in the PVN. The restoration of a normal oxytocin receptor density in the striatum paralleled the oxytocinergic stimulation produced by OEA. In conclusion, we provide evidence suggesting that OEA might represent a novel potential pharmacological target for the treatment of binge-like eating behavior.
Bcl-3 promotes Wnt signaling by maintaining the acetylation of β-catenin at lysine 49 in colorectal cancer
Authors: Chen Xi , Wang Chen , Jiang Yuhang , Wang Qi , Tao Yu , Zhang Haohao , Zhao Yongxu , Hu Yiming , Li Cuifeng , Ye Deji , Liu Dandan , Jiang Wenxia , Chin Eugene Y. , Chen Sheng , Liu Yongzhong , Wang Mingliang , Liu Sanhong , Zhang Xiaoren
Published: April 2020

Wnt/β-catenin signaling plays a critical role in colorectal cancer (CRC) tumorigenesis and the homeostasis of colorectal cancer stem cells (CSCs), but its molecular mechanism remains unclear. B-cell lymphoma 3 (Bcl-3), a member of the IκB family, is overexpressed in CRC and promotes tumorigenicity. Here, we report a novel function of Bcl-3 in maintaining colorectal CSC homeostasis by activating Wnt/β-catenin signaling. Silencing Bcl-3 suppresses the self-renewal capacity of colorectal CSCs and sensitizes CRC cells to chemotherapeutic drugs through a decrease in Wnt/β-catenin signaling. Moreover, our data show that Bcl-3 is a crucial component of Wnt/β-catenin signaling and is essential for β-catenin transcriptional activity in CRC cells. Interestingly, Wnt3a increases the level and nuclear translocation of Bcl-3, which binds directly to β-catenin and enhances the acetylation of β-catenin at lysine 49 (Ac-K49-β-catenin) and transcriptional activity. Bcl-3 depletion decreases the Ac-K49-β-catenin level by increasing the level of histone deacetylase 1 to remove acetyl groups from β-catenin, thus interrupting Wnt/β-catenin activity. In CRC clinical specimens, Bcl-3 expression negatively correlates with the overall survival of CRC patients. A significantly positive correlation was found between the expression of Bcl-3 and Ac-K49-β-catenin. Collectively, our data reveal that Bcl-3 plays a crucial role in CRC chemoresistance and colorectal CSC maintenance via its modulation of the Ac-K49-β-catenin, which serves as a promising therapeutic target for CRC.
Nanomedicines based on nanoscale metal-organic frameworks for cancer immunotherapy
Authors: Zhong Xiao-fang , Sun Xun
Published: April 2020

Cancer immunotherapy, with an aim to enhance host immune responses, has been recognized as a promising therapeutic treatment for cancer. A diversity of immunomodulatory agents, including tumor-associated antigens, adjuvants, cytokines and immunomodulators, has been explored for their ability to induce a cascading adaptive immune response. Nanoscale metal-organic frameworks (nMOFs), a class of crystalline-shaped nanomaterials formed by the self-assembly of organic ligands and metal nodes, are attractive for cancer immunotherapy because they feature tunable pore size, high surface area and loading capacity, and intrinsic biodegradability. In this review we summarize recent progress in the development of nMOFs for cancer immunotherapy, including cancer vaccine delivery and combination of in situ vaccination with immunomodulators to reverse immune suppression. Current challenges and future perspectives for rational design of nMOF-based cancer immunotherapy are also discussed.
Citron C-05 inhibits both the penetration and colonization of Xanthomonas citri subsp. citri to achieve resistance to citrus canker disease
Authors: Fu Hongyan , Zhao Mingming , Xu Jing , Tan Limei , Han Jian , Li Dazhi , Wang Meijun , Xiao Shunyuan , Ma Xianfeng , Deng Ziniu
Published: April 2020

Citrus canker, caused by Xanthomonas citri subsp. citri (Xcc), is a serious bacterial disease that affects citrus production worldwide. Citron C-05 (Citrus medica) is the only germplasm in the Citrus genus that has been identified to exhibit strong resistance to Xcc. However, it has not been determined when, where, and how Xcc is restricted in the tissues of Citron C-05 during the infection process. In the present study, we investigated the spatiotemporal growth dynamics of an eGFP-labeled virulent Xcc (eGFP-Xcc) strain in Citron C-05 along with five susceptible biotypes (i.e., lemon, pummelo, sour orange, sweet orange, and ponkan mandarin) upon inoculation via the spraying or leaf infiltration of a bacterial suspension. The results from extensive confocal laser scanning microscopy analyses showed that while Xcc grew rapidly in plants of all five susceptible genotypes, Xcc was severely restricted in the epidermal and mesophyll cell layers of the leaves of Citron C-05 in the early stage of infection. Not surprisingly, resistance against Xcc in Citron C-05 was found to be associated with the production of reactive oxygen species and hypersensitive response-like cell death, as well as greater upregulation of several defense-related genes, including a pathogenesis-related gene (PR1) and a glutathione S-transferase gene (GST1), compared with sweet orange as a susceptible control. Taken together, our results not only provide further valuable details of the spatiotemporal dynamics of the host entry, propagation, and spread of Xcc in both resistant and susceptible citrus plants but also suggest that resistance to Xcc in Citron C-05 may be attributed to the activation of multiple defense mechanisms.
PbMC1a/1b regulates lignification during stone cell development in pear (Pyrus bretschneideri) fruit
Authors: Gong Xin , Xie Zhihua , Qi Kaijie , Zhao Liangyi , Yuan Yazhou , Xu Jiahui , Rui Weikang , Shiratake Katsuhiro , Bao Jianping , Khanizadeh Shahrokh , Zhang Shaoling , Tao Shutian
Published: April 2020

Programmed cell death (PCD) and secondary cell wall (SCW) thickening in pear fruit are accompanied by the deposition of cellulose and lignin to form stone cells. Metacaspase is an important protease for development, tissue renewal and PCD. The understanding of the molecular mechanism whereby pear (Pyrus) metacaspase promotes PCD and cell wall lignification is still limited. In this study, theMetacaspasesgene family (PbMCs) fromP. bretschneideriwas identified.PbMC1a/1bwas associated with lignin deposition and stone cell formation by physiological data, semiquantitative real-time polymerase chain reaction (RT-PCR) and quantitative RT-PCR (qRT-PCR). Relative to wild-type (WT)Arabidopsis, the overexpression ofPbMC1a/1bincreased lignin deposition and delayed growth, thickened the cell walls of vessels, xylary fibers and interfascicular fibers, and increased the expression of lignin biosynthetic genes. Yeast two-hybrid (Y2H), bimolecular fluorescence complementation (BiFC) and GST pull-down assays indicated that the PbMC1a/1b protein physically interacted with PbRD21. Simultaneously, the transient expression ofPbMC1a/1bandPbRD21led to significant changes in the expression of genes and lignin contents in pear fruits and flesh calli. These results indicate thatPbMC1a/1bplays an important role in cell wall lignification, possibly by interacting withPbRD21to increase the mRNA levels of some lignin synthesis-associated genes and promote the formation of stone cells in pear fruit.