bluuebunny/crossref_metadata_2025 huggingface dataset:
Discriminant Analysis for Compositional Data Incorporating Cell-Wise Uncertainties
Authors: Pospiech Solveig , Tolosana-Delgado Raimon , van den Boogaart K. Gerald
Published: July 2020

In the geosciences it is still uncommon to include measurement uncertainties into statistical methods such as discriminant analysis, but, especially for trace elements, measurement uncertainties are frequently of relevant size. Uncertainties can be reported by each measured variable, by each observation or by individual cells (i.e., each observation has an individual uncertainty for each variable). Most methods incorporating uncertainties use the uncertainties as weights for the variables or observations of the data set. The method proposed in this contribution uses variance additivity properties and generalised least squares to calculate better estimates of group variances and group means, which then influence the decision rules of linear and quadratic discrimination algorithms. This methodological framework allows incorporation of cell-wise uncertainties, and would be largely valid if the information about co-dependency between variable errors within each observation were reported. The method is also appropriate for incorporating uncertainties into compositional data sets—for example, those formed by concentrations, proportions, percentages or any other form of information about the relative abundance of a set of components forming a whole—even if such uncertainties are nearly never reported considering this compositional nature. The methods are illustrated by means of case studies with simulated data.

Graphical abstract
The effect of message framing and the presentation of health vs. social consequences on health risk perception
Authors: Unger F. , Steul-Fischer M.
Published: July 2020

With health prevention campaigns health insurance providers can increase the perception of health risks among customers in order to promote healthy behaviour. The presentation format of health information has a significant influence on the health-related behaviour of customers. We investigate in our experimental study the impact of positive vs. negative presentation (message framing) as well as the presentation of health vs. social consequences in health prevention campaigns on health risk perception. The results reveal that loss- (vs. gain-) framed messages and the presentation of health (vs. social) consequences increase health risk perception more strongly. This effect is mediated by a stronger perceived severity of health (vs. social) consequences. Women perceive health (vs. social) consequences more likely and closer in time than men. Our findings show the importance of increasing health risk perception in order to promote healthy behaviour intentions.
Expansion of off-site percutaneous coronary intervention centres significantly reduces ambulance driving time to primary PCI in the Netherlands
Authors: Hoedemaker N. P. G. , de Winter R. J. , Kommer G. J. , Giesbers H. , Adams R. , van den Bosch S. E. , Damman P.
Published: July 2020

Introduction

In patients with ST-elevation myocardial infarction (STEMI), percutaneous coronary intervention (PCI)-mediated reperfusion is preferred over pharmacoinvasive reperfusion with fibrinolysis if transfer to a PCI centre can be ensured in ≤120 min. We evaluated the ambulance driving time to primary PCI centres in the Netherlands and assessed to what extent ambulance driving times were impacted by the expansion of off-site PCI centres.

Methods and results

We calculated the driving routes from every Dutch postal code to the nearest PCI centre with (on-site) or without (off-site) surgical back-up. We used data from ambulance records to estimate the ambulance driving time on each route. There were 16 on-site and 14 off-site PCI centres. The median (interquartile range) time to on-site PCI centres was 18.8 min (12.2–26.3) compared with 14.9 min (8.9–20.9) to any PCI centre (p < 0.001). In postal code areas that were impacted by the initiation of off-site PCI, the median driving time decreased from 25.4 (18.2–33.1) to 14.7 min (8.9–20.9) (p < 0.001). Ambulance driving times of >120 min were only seen in non-mainland areas.

Conclusion

Based on a computational model, timely ambulance transfer to a PCI centre within 120 min is available to almost all STEMI patients in the Netherlands. Expansion of off-site PCI has significantly reduced the driving time to PCI centres.
Early evidence of trepanation along the Yellow River Basin in Neolithic China
Authors: Zhou Yawei , Lin Shuang , Gu Wanfa , He Letian , Zhang Qun , Yeh Hui-Yuan
Published: July 2020

Trepanation is a long-lasting ancient practice found around the world with diverse motivations. However, the distribution and motivation of intentional trepanation in China remain unclear. This study presents one of the earliest trepanations on a male adult individual who is unearthed from the Shuanghuaishu site in Gongyi, Henan, dating back to the late Yangshao cultural period (3500–2900 BC). The macroscopic and microscopic observation, alongside with micro-CT scan, are conducted to further evaluate the conditions on the edges of the perforation and intracranial situation. The oval perforation is located on the occipital bone, and neither fracture nor apparent healing signs are observed on the margins. Archeological evidences and simulated experiment indicate that the trepanation could be conducted by drilling the tables of the skull with a V-bladed stone tool. In view of the location of the perforation and the limited details on the edges, the motivation behind the trepanation could be due to the medical treatment of trauma on the occipital bone or a postmortem ritual. The analysis of the early trepanation along the Yellow River Basin provides further evidence on the ancient human behavior and enriches our understanding of the origin and distribution of trepanation in Neolithic China.
Correction to: Ritual practices and social organisation at the Middle Yayoi culture settlement site of Maenakanishi, eastern Japan
Authors: Leipe Christian , Kuramochi Shunsuke , Wagner Mayke , Tarasov Pavel E.
Published: July 2020

The article “Ritual practices and social organisation at the Middle Yayoi culture settlement site of Maenakanishi, eastern Japan”, written by Christian Leipe, Shunsuke Kuramochi, Mayke Wagner and Pavel E. Tarasov.
Defect Probability Estimation for Hardness-Optimised Parts by Selective Laser Melting
Authors: Galetto Maurizio , Genta Gianfranco , Maculotti Giacomo , Verna Elisa
Published: July 2020

The development of reliable additive manufacturing (AM) technologies to process metallic materials, e.g. selective laser melting (SLM), has allowed their adoption for manufacturing final components. To date, ensuring part quality and process control for low-volume AM productions is still critical because traditional statistical techniques are often not suitable. To this aim, extensive research has been carried out on the optimisation of material properties of SLM parts to prevent defects and guarantee part quality. Amongst all material properties, defects in surface hardness are of particular concern as they may result in an inadequate tribological and wear resistance behaviour. Despite this general interest, a major void still concerns the quantification of their extent in terms of probability of defects occurring during the process, although it is optimised. Considering these issues, this paper proposes a novel approach to quantify the probability of occurrence of defects in hardness-optimised parts by SLM. First, three process variables, i.e. laser power, scan speed and hatching distance, are studied considering their effect on hardness. Design of Experiments and Response Surface Methodology are exploited to achieve hardness optimisation by controlling process variables. Then, hardness defect probability is estimated by composing the uncertainty affecting both process variables and their relationship with the hardness. The overall procedure is applied to AlSi10Mg alloy, which is relevant for both aerospace and automotive applications. The approach this study proposes may be of assistance to inspection designers to effectively and efficiently set up quality inspections in early design phases of inspection planning.
Metamizole relieves pain by influencing cytokine levels in dorsal root ganglia in a rat model of neuropathic pain
Authors: Zajaczkowska Renata , Kwiatkowski Klaudia , Pawlik Katarzyna , Piotrowska Anna , Rojewska Ewelina , Makuch Wioletta , Wordliczek Jerzy , Mika Joanna
Published: July 2020

Background

Treatment of neuropathic pain is still challenging. Recent studies have suggested that dorsal root ganglia (DRG), which carry sensory neural signals from the peripheral nervous system to the central nervous system, are important for pathological nociception. A proper understanding of the significance and function of DRG and their role in pharmacotherapy can help to improve the treatment of neuropathic pain. Metamizole, also known as sulpyrine or dipyrone, is a non-opioid analgesic commonly used in clinical practice, but it is not used for neuropathic pain treatment.

Methods

Chronic constriction injury (CCI) of the sciatic nerve was induced in Wistar rats. Metamizole was administered intraperitoneally (ip) preemptively at 16 and 1 h before CCI and then twice a day for 7 days. To evaluate tactile and thermal hypersensitivity, von Frey and cold plate tests were conducted, respectively.

Results

Our behavioral results provide evidence that repeated intraperitoneal administration of metamizole diminishes the development of neuropathic pain symptoms in rats. Simultaneously, our findings provide evidence that metamizole diminishes the expression of pronociceptive interleukins (IL-1beta, IL-6, and IL-18) and chemokines (CCL2, CCL4, and CCL7) in DRG measured 7 days after sciatic nerve injury. These assays indicate, for the first time, that metamizole exerts antinociceptive effects on nerve injury-induced neuropathic pain at the DRG level.

Conclusions

Finally, we indicate that metamizole-induced analgesia in neuropathy is associated with silencing of a broad spectrum of cytokines in DRG. Our results also suggest that metamizole is likely to be an effective medication for neuropathic pain.

Graphic abstract
The Montreal Protocol or the Paris Agreement as a Model for a Plastics Treaty?
Authors: Kirk Elizabeth A.
Published: July 2020

The notion that a plastics treaty is necessary is gaining traction, but there is less agreement as to its content. Some, including this author, have suggested that a plastics treaty should be modelled on treaties such as the Montreal Protocol, which sets out a broad commitment to end the use of a particular material and then introduce regulations to ban particular forms of that material over time. This approach has an immediate appeal—it sends a signal to states and to industry that they must change their behaviors and products, while giving time to adapt to the new regulation and develop alternative materials or ways of working. The potential drawback of this approach is that some states simply will not accept such rigid standards. In addition, some states may prefer a second approach that is more obviously rooted in the principle of common but differentiated responsibilities, which assigns different obligations to parties according to their respective capacities. Within the climate change regime, the Paris Agreement takes both approaches, asking states to set their own nationally determined contributions (NDCs) to emissions reductions (common but differentiated responsibilities) and then to revise these NDCs over time through an iterative process to deliver progressively more ambitious targets for emissions reduction (moving toward a ban) or mitigation. In reality, neither approach is entirely suited to regulating plastics, so a new approach to treaty-making is required. This new approach should focus on the outcomes desired rather than the practices that need to be regulated.
Liability and Compensation for Marine Plastic Pollution: Conceptual Issues and Possible Ways Forward
Authors: Maljean-Dubois Sandrine , Mayer Benoît
Published: July 2020

The UN General Assembly and the UN Environment Assembly (UNEA) have expressed concerns about the pollution of the sea by plastics, which adversely impacts ecosystems, some economic activities (e.g., tourism and fishing), and possibly public health (e.g., consumption of contaminated fish). In December 2017, the UNEA decided to establish the Ad Hoc Open-Ended Expert Group on Marine Litter and Microplastics to examine ways to combat marine plastic pollution. The group met three times in 2018 and 2019, and at least two more meetings are planned. Among potential responses to the issue of marine pollution, the group briefly considered—but eventually dismissed—the possibility of creating a liability or compensation regime. This essay evaluates the prospects for such a regime. As the essay will show, compensation faces significant conceptual problems, not the least of which is the absence of an obvious recipient. However, some form of liability could be imposed on corporations that produce plastic, or on states that fail to regulate them. Such a liability regime, even without financial compensation, could foster the prevention of further marine plastic pollution.
Fighting Plastics with Environmental Principles? The Relevance of the Prevention Principle in the Global Governance of Plastics
Authors: Duvic-Paoli Leslie-Anne
Published: July 2020

A common exercise for international lawyers faced with a new global environmental problem consists in undertaking a review of the applicable law. Environmental principles generally feature extensively in such studies: their open-textured nature is recognized to facilitate a fluid adaptation of international law as new risks become apparent. Among these principles is the foundational prevention principle, which is based on the rationale that environmental damage is best avoided rather than repaired. Since its international recognition in the 1972 Stockholm Declaration on the Human Environment, the prevention principle has gained an influential place in the work of environmental lawyers. While it is readily assumed that the principle is able to guide state responses to the plastics crisis, its exact functions and legal implications in this context remain underexplored. The purpose of this essay is to shed light on the different roles that the prevention principle can play in response to the proliferation of harmful plastics.
FIRST-ORDER RECOGNIZABILITY IN FINITE AND PSEUDOFINITE GROUPS
Authors: CORNULIER YVES , WILSON JOHN S.
Published: July 2020

It is known that there exists a first-order sentence that holds in a finite group if and only if the group is soluble. Here it is shown that the corresponding statements with ‘solubility’ replaced by ‘nilpotence’ and ‘perfectness’, among others, are false.

These facts present difficulties for the study of pseudofinite groups. However, a very weak form of Frattini’s theorem on the nilpotence of the Frattini subgroup of a finite group is proved for pseudofinite groups.
Kefir microbial composition is a deciding factor in the physiological impact of kefir in a mouse model of obesity
Authors: Bourrie Benjamin C. T. , Ju Tingting , Fouhse Janelle M. , Forgie Andrew J. , Sergi Consolato , Cotter Paul D. , Willing Benjamin P.
Published: July 2020

Kefir consumption has been demonstrated to improve lipid and cholesterol metabolism; however, our previous study identified that benefits vary between different commercial and traditional kefir. Here, we investigate the ability of pitched culture kefir, that is, kefir produced by a small number of specific strains, to recapitulate health benefits of a traditional kefir, in a diet-induced obesity mouse model, and examine how microbial composition of kefir impacts these benefits. Eight-week-old female C57BL/6 mice were fed a high-fat diet (40 % energy from fat) supplemented with one of five kefir varieties (traditional, pitched, pitched with no Lactobacillus, pitched with no yeast and commercial control) at 2 ml in 20 g of food for 8 weeks prior to analysis of plasma and liver lipid profiles, and liver gene expression profiles related to lipid metabolism. Both traditional and pitched kefir lowered plasma cholesterol by about 35 % (P = 0·0005) and liver TAG by about 55 % (P = 0·0001) when compared with commercial kefir despite no difference in body weight. Furthermore, pitched kefir produced without either yeast or Lactobacillus did not lower cholesterol. The traditional and pitched kefir with the full complement of microbes were able to impart corresponding decreases in the expression of the cholesterol and lipid metabolism genes encoding 3-hydroxy-3-methylglutaryl-coenzyme A reductase, PPARγ and CD36 in the liver. These results demonstrate that traditional kefir organisms can successfully be utilised in a commercial process, while highlighting the importance of microbial interactions during fermentation in the ability of fermented foods to benefit host health.
Codimension growth for weak polynomial identities, and non-integrality of the PI exponent
Authors: da Silva Macedo David Levi , Koshlukov Plamen
Published: July 2020

Let K be a field of characteristic zero. In this paper, we study the polynomial identities of representations of Lie algebras, also called weak identities, or identities of pairs. These identities are determined by pairs of the form (A, L) where A is an associative enveloping algebra for the Lie algebra L. Then a weak identity of (A, L) (or an identity for the representation of L associated to A) is an associative polynomial which vanishes when evaluated on elements of L⊆ A. One of the most influential results in the area of PI algebras was the theory developed by Kemer. A crucial role in it was played by the construction of the Grassmann envelope of an associative algebra and the close relation of the identities of the algebra and its Grassmann envelope. Here we consider varieties of pairs. We prove that under some restrictions one can develop a theory similar to that of Kemer's in the study of identities of representations of Lie algebras. As a consequence, we establish that in the case when K is algebraically closed, if a variety of pairs does not contain pairs corresponding to representations of sl2(K), and if the variety is generated by a pair where the associative algebra is PI then it is soluble. As another consequence of the methods used to obtain the above result, and applying ideas from papers by Giambruno and Zaicev, we were able to construct a pair (A, L) such that its PI exponent (if it exists) cannot be an integer. We recall that the PI exponent exists and is an integer whenever A is an associative (a theorem by Giambruno and Zaicev), or a finite-dimensional Lie algebra (Zaicev). Gordienko also proved that the PI exponent exists and is an integer for finite-dimensional representations of Lie algebras.
Crustal growth event in the Cathaysia Block at 2.5 Ga: evidence from chronology and geochemistry of captured zircons in Jurassic acidic dykes
Authors: Li Shuang-Lian , Lai Jian-Qing , Xiao Wen-Zhou , Belousova Elena A. , Rushmer Tracy , Zhang Le-Jun , Ou Quan , Liu Chao-Yun
Published: July 2020

Six acidic dykes were discovered surrounding the Laiziling pluton, Xianghualing area, in the western Cathaysia Block, South China. A number of captured zircons are found in two of these acidic dykes. By detailed U–Pb dating, Lu–Hf isotopes and trace-element analysis, we find that these zircons have ages clustered atc.2.5 Ga. Two acidic dyke samples yielded upper intersection point206U/238Pb ages of 2505 ± 42 Ma and 2533 ± 22 Ma, and weighted mean207Pb/206Pb ages of 2500 ± 30 Ma and 2535 ± 16 Ma. The majority of these zircons have high (Sm/La)N, Th/U and low Ce/Ce* ratios, indicating a magmatic origin, but some grains were altered by later hydrothermal fluid. Additionally, the magmatic zircons have high Y, U, heavy rare earth element, Nb and Ta contents, indicating that their host rocks were mainly mafic rocks or trondhjemite–tonalite–granodiorite rock series. Equally, their moderate Y, Yb, Th, Gd and Er contents also indicate that a mafic source formed in a continental volcanic-arc environment. These zircons have positive ϵHf(t) values (2.5–6.9) close to zircons from the depleted mantle, withTDM(2565–2741 Ma) andTDM2(2608–2864 Ma) ages close to their formation ages, indicating that these zircons originated directly from depleted mantle magma, or juvenile crust derived from the depleted mantle in a very short period. We therefore infer that the Cathaysia Block experienced a crustal growth event atc.2.5 Ga.
High-resolution computed tomography evaluation of congenital aural atresia – how useful is this?
Authors: Gautam R , Kumar J , Pradhan G S , Passey J C , Meher R , Mehndiratta A
Published: July 2020

Objective

To depict various temporal bone abnormalities on high-resolution computed tomography in congenital aural atresia patients, and correlate these findings with auditory function test results and microtia subgroup.

Methods

Forty patients (56 ears) with congenital malformation of the auricle and/or external auditory canal were evaluated. Auricles were graded according to Marx's classification, divided into subgroups of minor (grades I and II) and major (III and IV) microtia. Other associated anomalies of the external auditory canal, tympanic cavity, ossicular status, oval and round windows, facial nerve, and inner ear were evaluated.

Results

Minor and major microtia were observed in 53.6 and 46.4 per cent of ears respectively. Mean hearing levels were 62.47 and 62.37 dB respectively (p = 0.98). The malleus was the most commonly dysplastic ossicle (73.3 vs 80.8 per cent of ears respectively, p = 0.53). Facial nerve (mastoid segment) abnormalities were associated (p = 0.04) with microtia subgroup (80 vs 100 per cent in minor vs major subgroups).

Conclusion

Microtia grade was not significantly associated with mean hearing levels or other ear malformations, except for external auditory canal and facial nerve (mastoid segment) anomalies. High-resolution computed tomography is essential in congenital aural atresia, before management strategy is decided.
Nutrient sensing of gut luminal environment
Authors: Moran A. W. , Daly K. , Al-Rammahi M. A. , Shirazi-Beechey S. P.
Published: July 2020

Sensing of nutrients by chemosensory cells in the gastrointestinal tract plays a key role in transmitting food-related signals, linking information about the composition of ingested foods to digestive processes. In recent years, a number of G protein-coupled receptors (GPCR) responsive to a range of nutrients have been identified. Many are localised to intestinal enteroendocrine (chemosensory) cells, promoting hormonal and neuronal signalling locally, centrally and to the periphery. The field of gut sensory systems is relatively new and still evolving. Despite huge interest in these nutrient-sensing GPCR, both as sensors for nutritional status and targets for preventing the development of metabolic diseases, major challenges remain to be resolved. However, the gut expressed sweet taste receptor, resident in L-enteroendocrine cells and responsive to dietary sweetener additives, has already been successfully explored and utilised as a therapeutic target, treating weaning-related disorders in young animals. In addition to sensing nutrients, many GPCR are targets for drugs used in clinical practice. As such these receptors, in particular those expressed in L-cells, are currently being assessed as potential new pathways for treating diabetes and obesity. Furthermore, growing recognition of gut chemosensing of microbial-produced SCFA acids has led further attention to the association between nutrition and development of chronic disorders focusing on the relationship between nutrients, gut microbiota and health. The central importance of gut nutrient sensing in the control of gastrointestinal physiology, health promotion and gut–brain communication offers promise that further therapeutic successes and nutritional recommendations will arise from research in this area.
Academic achievement and schizophrenia: a systematic meta-analysis
Authors: Dickson Hannah , Hedges Emily P. , Ma Shin Y. , Cullen Alexis E. , MacCabe James H. , Kempton Matthew J. , Downs Johnny , Laurens Kristin R.
Published: July 2020

Background

Cognitive impairments in childhood are associated with increased risk of schizophrenia in later life, but the extent to which poor academic achievement is associated with the disorder is unclear.

Methods

Major databases were searched for articles published in English up to 31 December 2019. We conducted random-effects meta-analyses to: (1) compare general academic and mathematics achievement in youth who later developed schizophrenia and those who did not; (2) to examine the association between education level achieved and adult-onset schizophrenia; and, (3) compare general academic achievement in youth at-risk for schizophrenia and typically developing peers. Meta-regression models examined the effects of type of academic assessment, educational system, age at assessment, measurement of educational level attained, school leaving age, and study quality on academic achievement and education level among individuals with schizophrenia.

Results

Meta-analyses, comprising data of over four million individuals, found that: (1) by age 16 years, those who later developed schizophrenia had poorer general academic (Cohen's d = −0.29, p ⩽ 0.0001) and mathematics achievement (d = −0.23, p = 0.01) than those who did not; (2) individuals with schizophrenia were less likely to enter higher education (odds ratio = 0.49, p ⩽ 0.0001); and, (3) youth reporting psychotic-like experiences and youth with a family history of schizophrenia had lower general academic achievement (d = −0.54, p ⩽ 0.0001; d = −0.39, p ⩽ 0.0001, respectively). Meta-regression analyses determined no effect modifiers.

Discussion

Despite significant heterogeneity across studies, various routinely collected indices of academic achievement can identify premorbid cognitive dysfunction among individuals who are vulnerable for schizophrenia, potentially aiding the early identification of risk in the population.
Altered effective connectivity from the pregenual anterior cingulate cortex to the laterobasal amygdala mediates the relationship between internet gaming disorder and loneliness
Authors: Wang Min , Zeng Ningning , Zheng Hui , Du Xiaoxia , Potenza Marc N. , Dong Guang-Heng
Published: July 2020

Background

Individual with internet gaming disorder (IGD) often experience a high level of loneliness, and neuroimaging studies have demonstrated that amygdala function is associated with both IGD and loneliness. However, the neurobiological basis underlying these relationships remains unclear.

Methods

In the current study, Granger causal analysis was performed to investigate amygdalar subdivision-based resting-state effective connectivity differences between 111 IGD subjects and 120 matched participants with recreational game use (RGUs). We further correlated neuroimaging findings with clinical measures. Mediation analysis was conducted to explore whether amygdalar subdivision-based effective connectivity mediated the relationship between IGD severity and loneliness.

Results

Compared with RGUs, IGD subjects showed inhibitory effective connections from the left pregenual anterior cingulate cortex (pACC) to the left laterobasal amygdala (LBA) and from the right medial prefrontal cortex (mPFC) to the left LBA, as well as an excitatory effective connection from the left middle prefrontal gyrus (MFG) to the right superficial amygdala. Further analyses demonstrated that the left pACC-left LBA effective connection was negatively correlated with both Internet Addiction Test and UCLA Loneliness scores, and it mediated the relationship between the two.

Conclusion

IGD subjects and RGUs showed different connectivity patterns involving amygdalar subdivisions. These findings support a neurobiological mechanism for the relationship between IGD and loneliness, and suggest targets for therapeutic approaches that could be used to treat IGD.
Root traits of cover crops and carbon inputs in an organic grain rotation
Authors: Amsili Joseph P. , Kaye Jason P.
Published: July 2020

Cover crops are widely used to increase the quantity of organic carbon (C) returned to the soil between cash crops. Roots play an important role in increasing soil organic carbon (SOC) levels, but the root traits that impact SOC likely vary widely among cover crop species and this variation has yet to be characterized. Recently, cover crop mixtures have expanded in popularity as a way to increase the diversity of cover crop benefits. We tested the quantity, quality and spatial distribution of roots in three monocultures and one mixture to increase our understanding of root trait variation among species, and how that variation impacts mixture design. Root cores were taken from in-row and between-row locations to a depth of 40 cm from cover crops planted after winter wheat during the 2016–2017 growing season. These samples were taken from a larger maize–soybean–winter wheat organic grain rotation experiment (2012–2018) located in central Pennsylvania, USA. Cover crop treatments included monocultures of triticale (X Triticosecale Wittmack cv. ‘Trical 815’), canola (Brassica napus L. cv. ‘Wichita’), crimson clover (Trifolium incarnatum L. cv. ‘Dixie’) and a five species mixture dominated by those three species. Additionally, cumulative carbon (C) inputs were assessed for the entire rotation to determine cover crop and cash crop root C contributions. Root biomass C vertical and horizontal distribution, root-to-shoot (R:S) ratio, and root carbon-to-nitrogen (C:N) ratio differed among cover crop treatments. Triticale produced more root biomass in the between-row space at all depth intervals compared to other cover crop treatments. The five species mixture had more total 0–5 cm and between-row 0–5 cm root biomass than crimson clover in spring 2017. Cover crop and cash crop roots increased cumulative C estimates by between 37% (crimson clover) and 46% (triticale) compared to shoot C alone. Cover crop root trait information can inform the belowground benefits from combining different species into cover crop mixtures. Crimson clover produced less root biomass, surface root biomass and between-row root biomass than other cover crop treatments. Therefore, combining crimson clover with grass and certain brassica species can improve total root biomass production, and root distribution compared to crimson clover monocultures, whereas reducing the C:N ratio of roots compared to grass species monocultures. The five species mixture led to greater cumulative carbon inputs compared to monoculture treatments, which was due to greater cover crop biomass C and its influence on the following corn crop's biomass C.
Late-life depression in sub-Saharan Africa: lessons from the Ibadan Study of Ageing
Authors: Ojagbemi A. , Bello T. , Gureje O.
Published: July 2020

The population surviving to old age in sub-Saharan Africa (SSA) is increasing rapidly in consonance with the rest of the world. Nevertheless, the sub-region offers unique challenges to survival across the lifespan. The determinants of health and ageing in SSA are thus likely different from those in higher income countries. The need to explore pressing epidemiological and health service challenges of older people living in SSA in the context of multiple social changes and rapid ageing of the population provided the rationale for the Ibadan Study of Ageing (ISA). This article appraises ISA findings in relation to late-life depression. It concludes that healthcare policies in SSA need to deliberately prioritise the treatment of depression and other mental health problems in late-life in order to stem the neglect of older people's mental health in the region.
Accounting for Variability in ULF Wave Radial Diffusion Models
Authors: Thompson R. L. , Watt C. E. J. , Williams P. D.
Published: July 2020

Many modern outer radiation belt models simulate the long‐time behavior of high‐energy electrons by solving a three‐dimensional Fokker‐Planck equation for the drift‐ and bounce‐averaged electron phase space density that includes radial, pitch‐angle, and energy diffusion. Radial diffusion is an important process, often characterized by a deterministic diffusion coefficient. One widely used parameterization is based on the median of statistical ultralow frequency (ULF) wave power for a particular geomagnetic index Kp. We perform idealized numerical ensemble experiments on radial diffusion, introducing temporal and spatial variability to the diffusion coefficient through stochastic parameterization, constrained by statistical properties of its underlying observations. Our results demonstrate the sensitivity of radial diffusion over a long time period to the full distribution of the radial diffusion coefficient, highlighting that information is lost when only using median ULF wave power. When temporal variability is included, ensembles exhibit greater diffusion with more rapidly varying diffusion coefficients, larger variance of the diffusion coefficients and for distributions with heavier tails. When we introduce spatial variability, the variance in the set of all ensemble solutions increases with larger spatial scales of variability. Our results demonstrate that the variability of diffusion affects the temporal evolution of phase space density in the outer radiation belt. We discuss the need to identify important temporal and length scales to constrain variability in diffusion models. We suggest that the application of stochastic parameterization techniques in the diffusion equation may allow the inclusion of natural variability and uncertainty in modeling of wave‐particle interactions in the inner magnetosphere.
Martian Ice Revealed by Modeling of Simple Terraced Crater Formation
Authors: Martellato E. , Bramson A. M. , Cremonese G. , Lucchetti A. , Marzari F. , Massironi M. , Re C. , Byrne S.
Published: July 2020

Arcadia Planitia, a region in the northern midlatitudes of Mars, displays an uncommonly high abundance of simple craters with a concentric morphology, which is indicative of layering beneath the surface. Radar measurements suggest that the near surface layers could be made of excess water ice. In this study, we select two of these impact structures of similar size (Dc ~ 500 m), model their formation through iSALE shock physics code, and investigate the dependence of the final crater morphology on the material model parameters (cohesion and friction coefficient). Our parameter study shows that the intact and damaged cohesions of the nonporous ice play a fundamental role to obtain a good fit between our models and the topographic profiles taken from the digital terrain models in terms of crater diameter, crater wall inclination, and depth and size of the upper terrace. The central pit shape is instead controlled by the damaged friction coefficient of the basaltic crust, but it is mainly affected by projectile density and speed. Our results confirm that two layers of relatively pure water ice, each with different rheology and porosity, can explain the unique double‐terraced morphology of impact craters in Arcadia Planitia. The low values of cohesion we find for the ice might point to snowfall as emplacement mechanism in the region. The different thicknesses of the ice layers in the two crater areas seem to suggest variations in ice deposition and/or evolution history across Arcadia Planitia.
The Slab Puzzle of the Alpine‐Mediterranean Region: Insights From a New, High‐Resolution, Shear Wave Velocity Model of the Upper Mantle
Authors: El‐Sharkawy Amr , Meier Thomas , Lebedev Sergei , Behrmann Jan H. , Hamada Mona , Cristiano Luigia , Weidle Christian , Köhn Daniel
Published: July 2020

Mediterranean tectonics since the Lower Cretaceous has been characterized by a multiphase subduction and collision history with temporally and spatially variable, small‐scale plate configurations. A new shear wave velocity model of the Mediterranean upper mantle (MeRE2020), constrained by a very large set of over 200,000 broadband (8–350 s), interstation, Rayleigh wave, phase velocity curves, illuminates the complex structure and fragmentation of the subducting slabs. Phase velocity maps computed using these measurements were inverted for depth‐dependent, shear wave velocities using a stochastic particle‐swarm‐optimization (PSO) algorithm. The resulting three‐dimensional (3‐D) model makes possible an inventory of slab segments across the Mediterranean. Fourteen slab segments of 200–800 km length along‐strike are identified. We distinguish three categories of subducted slabs: attached slabs reaching down to the bottom of the model; shallow slabs of shorter length in downdip direction, terminating shallower than 300 km depth; and detached slab segments. The location of slab segments are consistent with and validated by the intermediate‐depth seismicity, where it is present. The new high‐resolution tomography demonstrates the intricate relationships between slab fragmentation and the evolution of the relatively small and highly curved subduction zones and collisional orogens characteristic of the Mediterranean realm.
Changes in Future Synoptic Circulation Patterns: Consequences for Extreme Event Attribution
Authors: Faranda Davide , Vrac Mathieu , Yiou Pascal , Jézéquel Aglaé , Thao Soulivanh
Published: July 2020

Anthropogenic emissions can modify the frequency and intensity of extreme weather events such as cold spells, heatwaves, and heavy precipitations. A major challenge is to detect changes in the atmospheric circulation patterns associated with those extreme events. The emergence of patterns depends on the chaotic behavior of the atmospheric flow and can also be modified by anthropogenic emissions. By embedding the circulation patterns observed during selected extremes into historical climate simulations and projections based on emission scenarios, we find major changes in probability, predictability, and persistence of atmospheric patterns observed during extreme events using an analog‐based method. The results highlight the need to take into account the role of atmospheric circulation in attribution studies as future extremes will be associated with modified circulation patterns.
Anthropogenic Nitrogen‐Induced Changes in Seasonal Carbonate Dynamics in a Productive Coastal Environment
Authors: Kim Ja‐Myung , Lee Kitack , Han In‐Seong , Lee Joon‐Soo , Choi Yang‐Ho , Lee Ju Hyeon , Moon Ji‐Young
Published: July 2020

We estimated the seasonal extremes in pH and the aragonite saturation state (Ωarag) for the Yellow Sea over the past 30 years using recent (2015–2018) carbonate data sets, along with historical data sets of surface N and bottom water dissolved O2 concentrations. The rate of increase in surface N was assumed to determine the postbloom surface dissolved inorganic C concentration resulting from the complete utilization of N by phytoplankton, while the decrease in bottom water O2 was assumed to reflect the prebloom surface C, as a consequence of C‐rich bottom water (resulting from the oxidation of greater amounts of organic matter transported from the surface) being brought to the surface. With the increasing loads of anthropogenic N, the net community metabolism (an increase in organic matter production at the surface and subsequent remineralization at the seafloor) has lowered the seasonal amplitude of pH by 0.14 but increased the amplitude of Ωarag by 0.8.
Meltwater Penetration Through Temperate Ice Layers in the Percolation Zone at DYE‐2, Greenland Ice Sheet
Authors: Samimi Samira , Marshall Shawn J. , MacFerrin Michael
Published: July 2020

Meltwater retention in the firn layer of the Greenland Ice Sheet has the potential to buffer sea level rise due to ice sheet melt. The capacity of the firn layer to store meltwater is unclear, however, because refrozen ice layers can act as impermeable barriers to meltwater percolation, promoting runoff rather than retention. We present time domain reflectometry and thermistor data, which demonstrate that meltwater successfully penetrates ice layers up to 12 cm thick in the near‐surface firn at DYE‐2, Greenland. Our observations indicate that ice layers within polar firn can be permeable when summer warming and latent heat release from meltwater refreezing raise firn temperatures to the melting point. The extent and depth of refreezing, as determined by the coupled thermodynamic and hydrological evolution in the firn, are more important than the presence of ice layers in governing meltwater infiltration and retention at our study site.
Experimental Investigations on the Effects of Dissolved Gases on the Freezing Dynamics of Ocean Worlds
Authors: Berton Mateo , Nathan Erica , Karani Hamid , Girona Társilo , Huber Christian , Williard Paul G. , Head James
Published: July 2020

The surfaces of icy moons are covered by fractures, other tectonic features, and active or ancient remains of cryovolcanism. These observations suggest active or recent tectonics, but there is still much unknown about the specific conditions surrounding the formation of these features. One important process leading to the fracture of the ice shell is the freezing and consequent pressurization of its ocean, because water expands upon freezing. However, the influence of dissolved non‐condensable gases (herein referred to as volatiles) on the aforementioned dynamics remains poorly constrained. In this study, we present a new experimental investigation to explore the effect of dissolved volatiles in the internal pressure evolution of 10 cm diameter water spheres subjected to freezing temperatures between ~−60°C and ~−20°C. Our experiments reveal that spheres with a reduced initial amount of volatiles dissolved undergo an abrupt transition with dramatic increase of (a) the time between consecutive ice shell fractures and (b) the pressure required to break the shell. We show from a simple numerical model that this transition occurs when exsolution (i.e., nucleation and growth of bubbles) occurs and the fluid inside the shell becomes significantly more compressible. Exsolution is, in turn, triggered by the gradual thickening of the ice shell, which increases the concentration of dissolved volatiles and eventually leads to saturation. These results suggest that the content of volatiles of icy satellites plays a significant role in their geologic history and potential for habitability.
Probability Distributions of Particle Hop Distance and Travel Time Over Equilibrium Mobile Bedforms
Authors: Ashley Thomas C. , Mahon Robert C. , Naqshband Suleyman , Leary Kate C. P. , McElroy Brandon
Published: July 2020

The joint probability distribution of streamwise particle hop distance, lateral particle hop distance, and travel time constrains the relationships between topographic change and sediment transport at the granular scale. Previous studies have investigated the ensemble characteristics of particle motions over plane bed topography; however, it is unclear whether reported distributions remain valid when bedforms are present. Here, we present measurements of particle motion over bedform topography obtained in a laboratory flume and compare these to particle motions over plane bed topography with otherwise similar conditions. We find substantial differences in particle motion in the presence of bedforms that are relevant to macroscopic models of sediment transport. Most notably, bedforms increase the standard deviation of streamwise and lateral hop distances relative to the mean streamwise hop distance. This implies that bedforms increase the streamwise and lateral diffusion lengths and, equivalently, increase diffusive‐like fluxes.
Iron is not everything: unexpected complex metabolic responses between iron-cycling microorganisms
Authors: Cooper Rebecca E , Wegner Carl-Eric , Kügler Stefan , Poulin Remington X , Ueberschaar Nico , Wurlitzer Jens D , Stettin Daniel , Wichard Thomas , Pohnert Georg , Küsel Kirsten
Published: July 2020

Coexistence of microaerophilic Fe(II)-oxidizers and anaerobic Fe(III)-reducers in environments with fluctuating redox conditions is a prime example of mutualism, in which both partners benefit from the sustained Fe-pool. Consequently, the Fe-cycling machineries (i.e., metal-reducing or –oxidizing pathways) should be most affected during co-cultivation. However, contrasting growth requirements impeded systematic elucidation of their interactions. To disentangle underlying interaction mechanisms, we established a suboxic co-culture system of Sideroxydans sp. CL21 and Shewanella oneidensis. We showed that addition of the partner’s cell-free supernatant enhanced both growth and Fe(II)-oxidizing or Fe(III)-reducing activity of each partner. Metabolites of the exometabolome of Sideroxydans sp. CL21 are generally upregulated if stimulated with the partner´s spent medium, while S. oneidensis exhibits a mixed metabolic response in accordance with a balanced response to the partner. Surprisingly, RNA-seq analysis revealed genes involved in Fe-cycling were not differentially expressed during co-cultivation. Instead, the most differentially upregulated genes included those encoding for biopolymer production, lipoprotein transport, putrescine biosynthesis, and amino acid degradation suggesting a regulated inter-species biofilm formation. Furthermore, the upregulation of hydrogenases in Sideroxydans sp. CL21 points to competition for H2 as electron donor. Our findings reveal that a complex metabolic and transcriptomic response, but not accelerated formation of Fe-end products, drive interactions of Fe-cycling microorganisms.
Increasing operational and scientific efficiency in clinical trials
Authors: Kelly Deirdre , Spreafico Anna , Siu Lillian L.
Published: July 2020

Operational and scientific inefficiencies in clinical trials represent roadblocks that need to be identified and circumvented to advance drug development in oncology. The collaboration of key stakeholders to advance this agenda is crucial to accelerate clinical research and ultimately benefit patient care through the optimal allocation of time and resources.
DDX5-targeting fully human monoclonal autoantibody inhibits proliferation and promotes differentiation of acute promyelocytic leukemia cells by increasing ROS production
Authors: Wu Jing , You Yan-Qiu , Ma Yan-Xiu , Kang Yan-Hua , Wu Tian , Wu Xiang-Ji , Hu Xiao-Xiao , Meng Qiao-Hong , Huang Yin , Zhang Na , Pan Xiao-Ben
Published: July 2020

Acute promyelocytic leukemia (APL) therapy involves the compounds cytotoxic to both malignant tumor and normal cells. Relapsed APL is resistant to subsequent chemotherapy. Novel agents are in need to kill APL cells selectively with minimal toxicity. DDX5 has been recognized to be a novel target to suppress acute myeloid leukemia (AML). However, the role of DDX5 remains elusive in APL. Here a DDX5-targeting fully human monoclonal autoantibody named after 2F5 was prepared. It is demonstrated that 2F5 selectively inhibited APL cell proliferation without toxicity to normal neutrophil and tissues. Moreover, 2F5 was confirmed to induce G0/G1 phase arrest in APL cells, and promote APL cell differentiation combined with decreased DDX5 expression and increased reactive oxygen species (ROS) production. Knockdown of DDX5 by siRNA also inhibited proliferation, promoted cell differentiation and enhanced ROS production in APL cells. However, the ROS inhibitor reversed the effects of 2F5 on DDX5 and ROS in APL cells. Thus, we conclude that DDX5-targeting 2F5 inhibits APL cell proliferation, and promotes cell differentiation via induction of ROS. 2F5 showed the therapeutic value of fully human monoclonal autoantibody in APL, which provides a novel and valid approach for treatment of relapse/refractory APL.