bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring the Relationship between Social Class and Quality of Life: the Mediating Role of Power and Status
Authors: Wingen Tobias , Englich Birte , Estal-Muñoz Víctor , Mareva Silvana , Kassianos Angelos P.
Published: July 2020

Why does social class affect Quality of Life? We simultaneously investigated two novel possible explanations: Because a high social class is associated with increased control over resources (i.e., power) or because a high social class is associated with higher respect and esteem in the eyes of others (i.e., status). To test these explanations, we collected data from 384 US-based individuals. We measured their social class, power, status, and four facets of Quality of Life (physical, mental, social, and environmental). For each facet, we calculated the correlation with social class. Next, we tested whether the relationship between social class and the specific facet was mediated by power, status, or both. Social class correlated significantly with all facets of Quality of Life (physical, mental, social, and environmental). Using parallel mediation models, we found that this positive relationship was mediated by status, but not by power. For some facets of Quality of Life (physical, environmental), power even had a negative indirect effect. These results suggest that upper-class individuals indeed have a higher Quality of Life. However, this seems to be mostly due to the increased status of upper-class individuals, whereas power was less important or even had detrimental effects on Quality of Life. Researchers and policymakers aiming to address class-based Quality of Life inequality could thus benefit from focusing on status as an important mediator. Moreover, our work demonstrates the importance of considering power and status as distinct constructs, in order to fully unravel the relationship between social class and Quality of Life.
An evaluation of live porcine simulation training for robotic surgery
Authors: Raison Nicholas , Poulsen Johan , Abe Takashige , Aydin Abdullatif , Ahmed Kamran , Dasgupta Prokar
Published: July 2020

To assess the role of live porcine simulation in robotic surgical skills training. A qualitative and quantitative survey was conducted of participants of a live porcine robotic simulation course undertaken in a regional training centre. Data on participants’ experience, robotic surgical ability, the educational impact and outcomes from the course were collected. Thirty-nine participants from four different countries completed the survey. Clinical experience varied; however, prior robotic surgical experience (median 0 cases, range 0–100) and technical ability were low. The perceived usefulness, effectiveness and realism of the training course were all highly scored. Participants rated the most useful course components as port placement and docking, basic robotic skills training and repair of a bladder injury. Training resulted in significant increases in technical ability (p < 0.0001). Following the course, 49% of participants continued to either train or perform robotic surgery. This survey demonstrates that live porcine simulation for robotic surgery is a highly valued, acceptable and feasible form of training. The majority of participants were relatively inexperienced but nonetheless significant improvements in technical ability were reported. The results of this survey support the use of live porcine training for robotic surgery.
What shapes our knowledge of the relationship between water deficiency stress and plant volatiles?
Authors: Szabó Krisztina , Zubay Péter , Németh-Zámboriné Éva
Published: July 2020

In this review, we attempt to highlight the issues related to plant volatile and essential oil studies in connection with drought stress. Our literature search included all publications on drought stress related to either the biosynthetic context of volatiles, or the ecophysiology and environmental interactions of species via these compounds. In addition, we surveyed publications on practical questions, such as the optimization of cultivation techniques of essential oil bearing plants. Emphasis was placed on theories explaining regularities in the detected symptoms of test plants and discrepancies of other results. Carbon allocation from primarily metabolism to secondary one, competition of parallel terpenoid pathways and the surplus of reductive power are the main theories that are discussed around. During evaluation, the main question was: which principles have already been justified in the biosynthesis/accumulation/emission of plant volatiles due to drought stress? What are the strengths and limitations of the theories? In discussing results from different scientific fields, the intention is to reveal logical connections that are yet to be addressed in the future co-operative multidisciplinary research. The simple question—whether drought stress increases the biosynthesis/accumulation/emission of plant volatiles—is not adequate any more. According to current scientific knowledge, the fine-tuning of all related variables is the challenge of next generation studies, especially for MAP species.
Hepatitis B Core Antibody: Role in Clinical Practice in 2020
Authors: Gish Robert G. , Basit Syed Abdul , Ryan John , Dawood Altaf , Protzer Ulrike
Published: July 2020

Purpose of Review

It is crucial for clinicians to understand the need to screen for hepatitis B core antigen (anti-HBc status), proper interpretation of HBV biomarkers, and that “anti-HBc only” indicates HBV exposure, lifelong persistence of cccDNA with incomplete infection control, and potential risk for reactivation.

Findings

Many common misconceptions exist, including that tests for anti-HBc have high false-positive rates, that patients with anti-HBc alone or occult hepatitis B may profit from “vaccine boosting” to achieve immune control of HBV, and that anti-HBc(+)/anti-HBs(+) patients have cleared HBV when they have actually achieved immune control, while HBV persists in some hepatocytes and can reactivate.

This review breaks down several common misconceptions regarding anti-HBc with the most recent evidence. In addition, current best strategies for anti-HBc testing and interpretation are reviewed and summarized.
Lean Stability Case Studies—Leveraging Science- and Risk-Based Approaches to Enable Meaningful Phase Specific Pharmaceutical Stability Strategies
Authors: Adamec Eric , Babayan Yelizaveta , Catacchio Bruno , Coon Angela , Dill Allison , Fu Mingkun , Gruenig Lars , Hyzer Cherokee Hoaglund , Lesslie Michael , McMahon Megan , Pulliam Donnie , Qiu Fenghe , Regler Brian P. , Szymulanska-Ramamurthy Karina , Timpano Robert , Wannere Chait
Published: July 2020

Purpose

Lean stability is a science- and risk-based initiative which utilizes the enhanced understanding of drug substance and drug product physical and chemical characteristics to (1) reduce and optimize the design of standard stability protocols; (2) expedite the generation of stability data without impact to safety, efficacy, or quality of the product; and (3) decrease time to market for innovative drugs. Lean stability was introduced in the early 2000s [ICH: Guideline Q1A(R2) (2003), ICH: Guideline Q1D (2002)] followed by reduced stability protocols, focusing on the critical quality attributes and critical time points, being reported in the literature [Skrdla et al. (J Pharm Biomed Anal 50: 794–796, 2009)]. While the concept of lean testing is not entirely new, and it is currently a part of several regulatory guidances, it continues to evolve and gain acceptance of the industry and regulators.

Methods

In this review, twelve case studies are presented where stability data was collected during clinical, registration, and post-approval phases of the product development.

Results

Case studies summarize the lean stability testing design, the strategies applied during the regulatory filing and the outcomes of the regulatory filings.

Conclusion

The authors expect that the case studies presented in this review will increase the visibility of lean stability, facilitate overcoming of the existing challenges, and accelerate the global regulatory acceptance of lean stability practices in the industry.
Cyanotoxin Analysis and Amino Acid Profiles of Cyanobacterial Food Items from Chad
Authors: Metcalf J. S. , Dunlop R. A. , Banack S. A. , Souza N. R. , Cox P. A.
Published: July 2020

In some parts of the world, cyanobacteria are used as a food in the human diet, due to their ready availability. Lake Chad, has long been a traditional site for the collection of Arthrospira fusiformis which is dried and processed at the lake into thin wafers called Dihé for later consumption or is transported to market for sale. However, Dihé purchased from markets in Chad has not been analyzed for known cyanobacterial toxins or assessed for total amino acid content. Since BMAA in traditional foodstuffs of the indigenous Chamorro people of Guam causes neurodegenerative illness, it is important that Dihé from Chad be analyzed for this neurotoxin. BMAA and its isomer AEG were not detected in our analyses, but a further isomer DAB was detected as both a free and bound amino acid, with an increase in the free concentration after acid hydrolysis of this fraction. Microcystins were present in 6 samples at up to 20 μg/g according to UPLC-PDA, although their presence could not be confirmed using PCR for known microcystin synthetic genes. Amino acid analysis of the cyanobacterial material from Chad showed the presence of large amounts of canonical amino acids, suggesting that this may supplement indigenous people on low protein diets, although regular monitoring of the foodstuffs for the presence of cyanotoxins should be performed.
Evaluating controls on potentially toxic element release in circum-neutral mine water: a case study from the abandoned Pb–Zn mines of Leadhills and Wanlockhead, South of Scotland, United Kingdom
Authors: Chukwura Uche O. , Hursthouse Andrew S.
Published: July 2020

Historic sulphidic Pb–Zn mining catchments at Leadhills and Wanlockhead, in the south of Scotland, UK have a legacy of mining of PbS (galena) and ZnS (sphalerite) from the twelfth century to the 1930s. The mining activities created tailing piles, ponds, adits and contaminated soils that contribute leaching and surface runoff of potentially toxic elements, particularly lead (Pb), which impact on the surface water and groundwater and are rapidly diluted in the wider catchment area. Studies by environmental regulators have shown that Pb, Cd and Zn in water can locally exceed the Environmental Quality Standards (EQS), particularly at Leadhills. To evaluate geochemical controls on release, 20 water sources (adits, surface water and near-surface groundwater) were sampled over four seasons (spring, summer, autumn and winter) over a 1-year period and characterized. Samples were circum-neutral pH from 6.3 to 7.9 (with average total dissolved solids < 55.0 mg/L), with no characteristics of acid mine drainage. The concentrations of PTEs in the water exceed UK EQS and WHO standards (and non-compliance on the Water Framework Directives). Geochemical modelling (GWB and PHREEQCv2) predicted mineral control on solubility which identified PbSO4 (anglesite), Fe2O3 ferric oxide (haematite), Fe3O4 (magnetite), FeCO3 (siderite), CaMg(CO3)2 (dolomite), CaCO3 (calcite) and Ca(Fe·Mg)(CO3)2 (ankerite) to be important. These were confirmed in solid phases analysed from tailings and sediments in contact with the hydrological cycle at the sites. Multivariate statistical analysis (PCA) of water samples associated with leaching through mine tailings showed strong seasonal variation with some elements (Fe, Cu, Cd, Pb, Na, Ca and Zn) with higher variance. The strong negative association of pH with soluble Zn, Cu, As, Cd and Pb highlights typical sulfide oxidation processes are taking place and supported by a positive correlation with temperature. Dissolution processes of mineral phases indicated by positive association of TDS and EC with Na, Ca and Zn. The data from PCA suggest contributions with potential for active generation of acid mine drainage and dissolution of solid phases influencing the release of PTEs into surface waters.
Constructing and Extending Description Logic Ontologies using Methods of Formal Concept Analysis
Authors: Kriegel Francesco
Published: July 2020

My thesis describes how methods from Formal Concept Analysis can be used for constructing and extending description logic ontologies. In particular, it is shown how concept inclusions can be axiomatized from data in the description logics $$\mathcal {E}\mathcal {L}$$

E
L

, $$\mathcal {M}$$
M
, $$\textsf {Horn}$$
Horn
-$$\mathcal {M}$$
M
, and $$\textsf{Prob}\text{-}\mathcal {E}\mathcal {L}$$

Prob
-
E
L

. All proposed methods are not only sound but also complete, i.e., the result not only consists of valid concept inclusions but also entails each valid concept inclusion. Moreover, a lattice-theoretic view on the description logic $$\mathcal {E}\mathcal {L}$$

E
L

is provided. For instance, it is shown how upper and lower neighbors of $$\mathcal {E}\mathcal {L}$$

E
L

concept descriptions can be computed and further it is proven that the set of $$\mathcal {E}\mathcal {L}$$

E
L

concept descriptions forms a graded lattice with a non-elementary rank function.
The effectiveness of diabetes self-management education (DSME) on glycemic control among T2DM patients randomized control trial: systematic review and meta-analysis protocol
Authors: Bekele Bayu Begashaw , Negash Samuel , Bogale Biruk , Tesfaye Melkamsew , Getachew Dawit , Weldekidan Fekede , Balcha Behailu
Published: July 2020

Background

Type 2 Diabetes mellitus (T2DM) has been a global pandemic resulting in physical, financial and psychosocial crises. Thus, it is important to investigate pooled effectiveness of Diabetes Self-Management Education (DSME) on glycemic control among T2DM patients.

Objective

The aim of this systematic review and meta-analysis is to investigate the association between DSME or Support (DSME/S) and glycemic control among T2DM patients.

Methods

The systematic review and meta-analysis will include studies conducted throughout the world from 2010 to 2019. T2DM patients and their clinical, anthropometric, biomarkers from baseline to end line will be recorded. We will search all relevant articles from five databases namely; Cochrane Library, BioMed Central, MEDLINE (EBSCOhost), MEDLINE/PubMed and SCOPUS. Key terms will be used for questing relevant articles. Further efforts will be made to check quality of studies base on quality assessment instruments. Finally, the report will be made according Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. Pooled standard mean difference in HbA1c will be used to calculate the effect size between the variables with random effects analysis assumption. Further subgroup analysis will be carried out for assessing the risk difference among groups.

Conclusion

Based on the existing and eligible researches this systematic review and meta-analysis will bring the best evidence on the effectiveness of DSME/S on glycemic control among the T2DM patients. Moreover, the subgroup analysis will inform the effectiveness heterogeneity based on continent, International Diabetes Federation (IDF) region, intervention period, World bank economic classification and glycemic markers used to follow the patients. The proposed review has been registered in the International PROSPERO website with registration number CRD42020124236.
European SMEs amidst the COVID-19 crisis: assessing impact and policy responses
Authors: Juergensen Jill , Guimón José , Narula Rajneesh
Published: July 2020

We consider how the COVID-19 pandemic has challenged European small- and medium-sized enterprises (SMEs) in the manufacturing sector, and draw suggests policy implications. The sudden onslaught of the pandemic has acted as an economic shock, and we consider how it is likely to affect different types of manufacturing SMEs. We distinguish between immediate effects, a result of the almost-simultaneous lockdowns across Europe and its major trading partners, and longer-term implications for both SMEs and the global value chains where they are inserted. In the shorter run, most SMEs have faced logistical challenges in addition to demand disruptions, although the severity has differed across firms and industries. We argue that in the longer-term, there will be different challenges and opportunities depending on the type of SME. Policy interventions will also need to be sensitive to the different types of SMEs, rather than adopting a one-size-fits-all approach. The policy mix will need to shift from its initial focus on the survival of European SMEs in the short term, towards a more structural and longer-term approach based on promoting their renewal and growth through innovation, internationalization and networking.
The mobility network of scientists: analyzing temporal correlations in scientific careers
Authors: Vaccario Giacomo , Verginer Luca , Schweitzer Frank
Published: July 2020

The mobility of scientists between different universities and countries is important to foster knowledge exchange. At the same time, the potential mobility is restricted by geographic and institutional constraints, which leads to temporal correlations in the career trajectories of scientists. To quantify this effect, we extract 3.5 million career trajectories of scientists from two large scale bibliographic data sets and analyze them applying a novel method of higher-order networks. We study the effect of temporal correlations at three different levels of aggregation, universities, cities and countries. We find strong evidence for such correlations for the top 100 universities, i.e. scientists move likely between specific institutions. These correlations also exist at the level of countries, but cannot be found for cities. Our results allow to draw conclusions about the institutional path dependence of scientific careers and the efficiency of mobility programs.
An alternative approach to frequentist meta‐analysis: A demonstration of Bayesian meta‐analysis in adolescent development research
Authors: Thompson Christopher G. , Semma Brandie
Published: July 2020

Introduction

Past decades have seen a surge of applied and methodological research on meta‐analysis. One methodological advancement that has gained significant traction is a Bayesian approach to meta‐analysis.

Methods

We present a non‐technical introduction to Bayesian meta‐analysis. This introduction re‐analyzes data from a meta‐analysis concerning the impact of media literacy interventions on attitudes and intentions related to risky health behaviors using a Bayesian approach. One data relate media literacy interventions to media literacy skills, and another relates media literacy interventions to attitudes and behavioral intentions towards risky health behaviors. In these examples we focus on how to conduct unconditional models via graphical and quantitative results. Further, we demonstrate how to conduct subgroup analyses using risk behavior type (drinking, sexual, or smoking).

Results

We demonstrated how several meta‐analytical quantities could be computed and interpreted in a Bayesian framework. This was done both graphically (plot of the marginal posterior distributions) and quantitatively (e.g., central tendency measures, highest posterior density intervals). Results also showed how analyzing effect sizes at the risk‐behavior level could affect several interpretations.

Conclusions

We emphasize that in no way are Bayesian methods “superior” to frequentist methods, nor that frequentist methods should be abandoned. Instead, the two approaches should be viewed as familial, each with advantages and disadvantages, but strive at a common purpose. We hope for increased use of Bayesian meta‐analyses, and Bayesian methodology at large, in adolescence research. Last, all R code is provided for readers to use as a foundation for their own research.
The effect of family and neighbourhood social capital on youth mental health in South Africa
Authors: Somefun Oluwaseyi Dolapo , Simo Fotso Arlette
Published: July 2020

Introduction

Despite the prevalence of mental illness among young adults in South Africa, few studies have examined its correlation with social capital using nationally representative data. Sources of social capital are different for youth, which is why understanding the correlation between family and neighbourhood social capital and mental health outcomes is important for designing optimal interventions. The objective of this study was to examine the relationship between social capital and youth mental health. We also sought to understand whether family social capital was more protective for the mental health of youth compared to neighbourhood social capital.

Methods

Using the National Income Dynamics Survey data for South Africa, we examine these associations among 2307 youth aged 15–24 across the four waves. Multilevel logistic regression was used to examine these associations.

Results

Our findings emphasize the substantial burden of mental illness among youth in South Africa (26% in wave 4). Although results for parental presence were not significant, family social capital measured by household income significantly decreased the odds of incident depression only for those belonging to the third quintile (aOR 0.74, 95% CI 0.54–1.01). High perception of crime in the neighbourhood was associated with significantly higher odds of incident depression (aOR 1.33, 95% CI 1.06–1.67).

Conclusions

Our results confirm the independent effect of neighbourhood characteristics on youth mental health and did not support family social capital as being protective for developing depression. This implies that youth program planners must focus on community context in improving youth developmental outcomes such as mental health.
The circumstances of migrant families raising children with disabilities in five European countries
Authors: Piérart Geneviève , Arneton Melissa , Gulfi Alida , Albertini-Früh Elena , Lidén Hilde , Makharadze Tamar , Rekhviashvili Eliso , Dainese Roberto
Published: July 2020

In 2017, specialists in several fields (health, education, and social work) from five European countries (France, Georgia, Italy, Norway, and Switzerland) established a network to jointly pursue studies on migration and disability. An initial workshop provided an opportunity to discuss their previous individual work and to develop a comparative research project. This article presents the key aspects of the discussion and the resulting plans for collaborative study. First, migrant children with disabilities remain statistically invisible in some countries. Separate policies and systems address their needs as migrants and their needs as persons with disabilities. Second, in all countries covered by the research network, there is an important gap between legal norms and the circumstances of migrant families raising children with disabilities. The same holds true for collaboration between public agencies, or between those agencies and NGOs (serving persons with disabilities, migrants, and/or national minorities). Further comparative and cross-disciplinary study must focus on increasing the social participation of children with disabilities and their families through social, educational, and health interventions within an intercultural context.
Bifurcation for minimal surface equation in hyperbolic 3-manifolds
Authors: Huang Zheng , Lucia Marcello , Tarantello Gabriella
Published: July 2020

Initiated by the work of Uhlenbeck in late 1970s, we study existence, multiplicity and asymptotic behavior for minimal immersions of a closed surface in some hyperbolic three-manifold, with prescribed conformal structure on the surface and second fundamental form of the immersion. We prove several results in these directions, by analyzing the Gauss equation governing the immersion. We determine when existence holds, and obtain unique stable solutions for area minimizing immersions. Furthermore, we find exactly when other (unstable) solutions exist and study how they blow-up. We prove our class of unstable solutions exhibit different blow-up behaviors when the surface is of genus two or greater. We establish similar results for the blow-up behavior of any general family of unstable solutions. This information allows us to consider similar minimal immersion problems when the total extrinsic curvature is also prescribed.
Air pollution and chronic obstructive pulmonary disease
Authors: Duan Rui‐Rui , Hao Ke , Yang Ting
Published: July 2020

There is considerable epidemiological evidence indicating that air pollution has adverse effects on human health and is closely related to respiratory diseases, including chronic obstructive pulmonary disease (COPD). These effects, which can be divided into short‐ and long‐term effects, can manifest as an exacerbation of existing symptoms, impaired lung function, and increased hospitalization and mortality rates. Long‐term exposure to air with a high concentration of pollutants may also increase the incidence of COPD. The combined effects of different pollutants may become more complex in the future; hence, there is a need for more intensive research on specific at‐risk populations, and formulating corresponding protective strategies is crucial. We aimed to review the epidemiological evidence on the effect of air pollution on COPD, the possible pathophysiological mechanisms underlying this effect, as well as protective measures against the effects of air pollutants in patients with COPD.
Study of material removal behavior on R-plane of sapphire during ultra-precision machining based on modified slip-fracture model
Authors: Kwon Suk Bum , Nagaraj Aditya , Yoon Hae-Sung , Min Sangkee
Published: July 2020

In this paper, the modified slip/fracture activation model has been used in order to understand the mechanism of ductile-brittle transition on the R-plane of sapphire during ultra-precision machining by reflecting direction of resultant force. Anisotropic characteristics of crack morphology and ductility of machining depending on cutting direction were explained in detail with modified fracture cleavage and plastic deformation parameters. Through the analysis, it was concluded that crack morphologies were mainly determined by the interaction of multiple fracture systems activated while, critical depth of cut was determined by the dominant plastic deformation parameter. In addition to this, by using proportionality relationship between magnitude of resultant force and depth of cut in the ductile region, an empirical model for critical depth of cut was developed.
Chemical superglue: Improving adhesion with molecules
Authors: Nickels Liz
Published: July 2020

A new way of finishing reinforced plastic surfaces at the molecular level could lead to better bonding and a wider range of materials, according to a small UK company.
Where Is the Io Plasma Torus? A Comparison of Observations by Juno Radio Occultations to Predictions From Jovian Magnetic Field Models
Authors: Phipps Phillip H. , Withers Paul , Vogt Marissa F. , Buccino Dustin R. , Yang Yu‐Ming , Parisi Marzia , Ranquist Drake , Kollmann Peter , Bolton Scott
Published: July 2020

The Io plasma torus is thought to lie in Jupiter's centrifugal equator, a location that depends on Jupiter's rotation and magnetic field. Yet previous observations and predictions of the location of the Io plasma torus are inconsistent. Here we test the hypothesis that the Io plasma torus lies in the centrifugal equator by comparison of observations by Juno radio occultations to predictions derived from Juno‐era magnetic field models. These observations determine the locations of two torus components: The cold torus is centered near 5.3 Jovian radii (RJ), and the “torus beyond 5.5 RJ,” dominated by the warm torus, is centered near 5.9 RJ. The observations deviate by 1–2° from the planar centrifugal equator expected for a Voyager epoch dipolar magnetic field. In each observation, the locations of distinct torus regions differ by as much as 1° indicating significant radial structure. The root‐mean‐square error between observation and prediction is smaller for predictions from the JRM09 magnetic field model than for predictions from the VIP4 magnetic field model, confirming the JRM09 model is an improvement over the VIP4 model. Agreement between observations and predictions improves for the warm torus if the magnetic field contributions of a nominal magnetospheric current sheet model are included but worsens for the cold torus. Magnetic field conditions around 5.3 RJ are adequately represented by an internal field model without the current sheet. Conditions around 5.9 RJ require internal and external contributions. These results place constraints on properties of the magnetospheric current sheet during the Juno epoch.
Modeling the Effect of Pressure on the Moduli Dispersion in Fluid‐Saturated Rocks
Authors: Sun Yongyang , Gurevich Boris
Published: July 2020

Laboratory experiments of ultrasonic velocities of fluid‐saturated rocks are often much higher than the predictions of the Gassmann theory. This difference is usually attributed to the velocity dispersion caused by fluid pressure relaxation between pores of different shapes and orientation. This paper proposes a simple model to characterize pressure and frequency effects on the elastic moduli of fluid‐saturated rocks in a broad frequency range. The proposed model incorporates micromechanics of wave‐induced fluid pressure relaxation at grain contacts (between crack‐like contacts and stiff pores) into pressure dependency of elastic moduli. Previously, the pressure dependency of the velocities or elastic moduli was ascribed to the progressive closure of cracks with the increasing effective pressure and expressed as an integral of crack compliance over the range of aspect ratios. For isolated cracks, this compliance is a function of crack geometry only. For cracks hydraulically connected to stiff pores, this crack compliance can be replaced by a frequency‐dependent solution of the micromechanical problem of fluid pressure relaxation between a single crack and surrounding pores. The resulting equation expresses the bulk and shear moduli of the fluid‐saturated rock as functions of both pressure and frequency. Furthermore, if pressure‐dependent moduli of both dry and fluid‐saturated moduli are known, the aspect ratio distribution can be obtained from the pressure dependency of the dry moduli, and then the saturated moduli can be computed with no adjustable parameters. The model predictions show reasonable agreement with laboratory data measured using ultrasonic and forced oscillation techniques.
The Role of Fire in the Coevolution of Soils and Temperate Forests
Authors: Inbar Assaf , Nyman Petter , Lane Patrick N. J. , Sheridan Gary J.
Published: July 2020

Climate drives the coevolution of vegetation and the soil that supports it. Wildfire dramatically affects many key eco‐hydro‐geomorphic processes, but its potential role in coevolution of soil‐forest systems has been largely overlooked. The steep landscapes of southeastern Australia provide an excellent natural laboratory to study the role of fire in the coevolution of soil and forests, as they are characterized by temperate forest types, fire frequencies, and soil depths that vary systematically with aridity. The aims of this study were (i) to test the hypothesis that in Southeastern Australia, fire‐related processes are critical to explain the variations in coevolved soil‐forest system states across an aridity gradient and (ii) to identify the key processes and (iii) feedbacks involved. To achieve these aims, we developed a numerical model that simulates the coevolution of soil‐forest systems which employ eco‐hydro‐geomorphic processes that are typical of the flammable forests of southeastern Australia. A stepwise model evaluation, using measurements and published data, confirms the robustness of the model to simulate eco‐hydro‐geomorphic processes across the aridity gradient. Simulations that included fire replicated patterns of observed soil depth and forest cover across an aridity gradient, supporting our hypothesis. The contribution of fire to coevolution increased in magnitude with aridity, mainly due to the higher fire frequency and lower post‐fire infiltration capacity, increasing the rates of fire‐related surface runoff and erosion. Our results show that critical feedbacks between soil depth, vegetation, and fire frequency dictate the trajectory and pace of the coevolution of flammable temperate forests and soils.
Hydrologic Signals and Surprises in U.S. Streamflow Records During Urbanization
Authors: Bhaskar A. S. , Hopkins K. G. , Smith B. K. , Stephens T. A. , Miller A. J.
Published: July 2020

Urban development has been observed to lead to variable magnitudes of change for stormflow volume and directions of baseflow change across cities. This work examines temporal streamflow trends across the flow duration curve in 53 watersheds during periods of peak urban development, which ranged from 1939 to 2016. We used U.S. Geological Survey streamgage records combined with pre‐development and urbanization characteristics to identify 20 years for analysis in each urbanizing watershed. Each urbanizing gage was paired with a nearby reference gage representing climatic trends over the same time period. Results indicated that urbanization, as measured by housing density, did not homogeneously alter the flow duration curve. Urbanization led to widely variable trends in low flow, where half of the urbanizing gages had increasing flow at the 10th non‐exceedance percentile, and the other half had declining low flow. High flows generally increased in streams as the area urbanized. The largest increases in high flows were in streams in semi‐arid and arid areas. The largest urban flow changes had transformations in wastewater infrastructure, water supply infrastructure, and flood control facilities. Isolating flow changes due to urbanization from those of reference sites will serve to better identify and manage synergistic effects of urban development and climate change on flooding and water availability.
Accessory Mineral Eu Anomalies in Suprasolidus Rocks: Beyond Feldspar
Authors: Holder R. M. , Yakymchuk C. , Viete D. R.
Published: July 2020

Accessory mineral Eu anomalies (Eu/Eu*) are routinely measured to infer changes in the amount of feldspar over time, allowing accessory mineral U‐Pb dates to be linked to the progressive crystallization of igneous and metamorphic rocks and, by extension, geodynamic processes. However, changes in Eu/Eu* can reflect any process that changes the relative availability of Eu2+ and Eu3+. We constructed partitioning budgets for Sm, Eu2+, Eu3+, and Gd in suprasolidus metasedimentary rocks to investigate processes that can influence accessory mineral Eu anomalies. We modeled three scenarios: (1) closed‐system, equilibrium crystallization; (2) fractionation of Eu by feldspar growth during melt crystallization; and (3) removal of Eu by melt extraction. In the closed‐system equilibrium model, accessory mineral Eu/Eu* changes as a function of fO2 and monazite stability; Eu/Eu* changes up to 0.3 over a pressure‐temperature range of 4–12 kbar and 700–950°C. Fractionation of Eu by feldspar growth is modeled to decrease accessory mineral Eu/Eu* by ~0.05–0.15 per 10 wt% feldspar crystallized. Melt extraction has a smaller effect; removal of 10% melt decreases accessory mineral Eu/Eu* in the residue by ≤0.05. Although these models demonstrate that fractionation of Eu by feldspar growth can be a dominant control on a rocks u budget, they also show that the common interpretation that Eu/Eu* only records feldspar growth and breakdown is an oversimplification that could lead to incorrect interpretation about the duration and rates of tectonic processes. Consideration of other processes that influence Eu anomalies will allow for a broader range of geological processes to be investigated by petrochronology.
Model for (De)Compaction and Porosity Waves in Porous Rocks Under Shear Stresses
Authors: Yarushina V. M. , Podladchikov Y. Y. , Wang L. H.
Published: July 2020

An understanding of instantaneous and long‐term compaction of porous rocks is important for reservoir engineering and Earth sciences. Experience from laboratory triaxial compression tests and from subsurface operations indicates that shear and volumetric deformations are interdependent. Their mutual dependence results in shear‐enhanced compaction and shear‐induced dilation under short‐term and long‐term loading. Using a classical averaging approach, we consider the evolution of a single fluid‐filled pore in a solid elastoplastic or viscoplastic matrix under combined pressure and shear loading to introduce a new failure envelope and 3‐D constitutive relations for both rate‐dependent and rate‐independent deformation of porous rocks. Our model provides a simple description of rock behavior under a wide range of strain rates. The model predictions agree well with experimental data from triaxial instantaneous and creep tests. Analytical and numerical solutions for solitary porosity wave propagation in viscoplastic rocks in the presence of shear were obtained. New solutions show that new rheological laws have serious implications for porosity waves. Plasticity onset leads to compaction‐decompaction asymmetry and the formation of elongated channel‐like porosity waves. Shear‐induced dilation facilitates porosity wave propagation at fluid pressures below the lithostatic stress. This makes porosity waves a viable mechanism in the formation of focused fluid flow structures in crustal rocks.
Size‐Fractionated Compositions of Marine Suspended Particles in the Western Arctic Ocean: Lateral and Vertical Sources
Authors: Xiang Yang , Lam Phoebe J.
Published: July 2020

We present full water depth sections of size‐fractionated (1–51 μm; >51 μm) concentrations of suspended particulate matter and major particle phase composition (particulate organic matter [POM], including its carbon isotopic composition [POC‐δ13C] and C:N ratio, calcium carbonate [CaCO3], opal, lithogenic particles, and iron and manganese [oxyhydr]oxides) from the U.S. GEOTRACES Arctic Cruise (GN01) in the western Arctic in 2015. Whereas biogenic particles (POM and opal) dominate the upper 1,000 m, lithogenic particles are the most abundant particle type at depth. Minor phases such as manganese (Mn) oxides are higher in GN01 than in any other U.S. GEOTRACES cruises so far. Extremely depleted POC‐δ13C, as low as ~ −32‰, is ubiquitous at the surface of the western Arctic Ocean as a result of different growth rates of phytoplankton. Moderate penetration of depleted POC‐δ13C to depth indicates active sinking of large particles in the central basin. Lateral transport from the Chukchi shelf is also of significance in the western Arctic, as is evident from increases in biogenic silica to POC ratios and Mn oxide concentrations in the halocline, as well as lithogenic element contents in the deep waters. Our study supports previous suggestions of the near absence of CaCO3 in the Arctic Basin. This study presents the first data set of concentration and composition of suspended particles in the western Arctic Ocean and sheds new light on the vertical and lateral processes that govern particle distribution in this enclosed ocean basin.
A New Crater Near InSight: Implications for Seismic Impact Detectability on Mars
Authors: Daubar I. J. , Lognonné P. , Teanby N. A. , Collins G. S. , Clinton J. , Stähler S. , Spiga A. , Karakostas F. , Ceylan S. , Malin M. , McEwen A. S. , Maguire R. , Charalambous C. , Onodera K. , Lucas A. , Rolland L. , Vaubaillon J. , Kawamura T. , Böse M. , Horleston A. , van Driel M. , Stevanović J. , Miljković K. , Fernando B. , Huang Q. , Giardini D. , Larmat C. S. , Leng K. , Rajšić A. , Schmerr N. , Wójcicka N. , Pike T. , Wookey J. , Rodriguez S. , Garcia R. , Banks M. E. , Margerin L. , Posiolova L. , Banerdt B.
Published: July 2020

A new 1.5 m diameter impact crater was discovered on Mars only ~40 km from the InSight lander. Context camera images constrained its formation between 21 February and 6 April 2019; follow‐up High Resolution Imaging Science Experiment images resolved the crater. During this time period, three seismic events were identified in InSight data. We derive expected seismic signal characteristics and use them to evaluate each of the seismic events. However, none of them can definitively be associated with this source. Atmospheric perturbations are generally expected to be generated during impacts; however, in this case, no signal could be identified as related to the known impact. Using scaling relationships based on the terrestrial and lunar analogs and numerical modeling, we predict the amplitude, peak frequency, and duration of the seismic signal that would have emanated from this impact. The predicted amplitude falls near the lowest levels of the measured seismometer noise for the predicted frequency. Hence, it is not surprising this impact event was not positively identified in the seismic data. Finding this crater was a lucky event as its formation this close to InSight has a probability of only ~0.2, and the odds of capturing it in before and after images are extremely low. We revisit impact‐seismic discriminators in light of real experience with a seismometer on the Martian surface. Using measured noise of the instrument, we revise our previous prediction of seismic impact detections downward, from ~a few to tens, to just ~2 per Earth year, still with an order of magnitude uncertainty.
Evaluation of Physics‐Based Data Assimilation System Driven by Neutral Density Data From a Single Satellite
Authors: Ren Dexin , Lei Jiuhou
Published: July 2020

Accurate forecast of the thermospheric density is critical to the space community. The data assimilation approach that is based on the self‐consistent upper‐atmosphere model may provide better predictive capability of the coupled thermosphere system. In this study, a physics‐based assimilation system (hereafter referred to as PIDA) that is based on the Thermosphere‐Ionosphere‐Electrodynamics General Circulation Model was used to validate the capability of reproducing the evolution of the global thermosphere state. The effective solar and geophysical drivers were estimated by ingesting neutral density from a single satellite into the PIDA. It was found that the PIDA can reproduce the temporal variation of the global thermospheric density at around the altitude where the orbit density was ingested. Furthermore, the PIDA is also capable of capturing the temporal evolution of the thermospheric density at various altitudes. However, a systematic bias, depending on altitude, is seen in the modeled neutral density of the PIDA. Moreover, this systematic bias in the thermospheric density is likely ascribed to the overestimation of the density in the lower thermosphere. Consequently, the spatial and temporal evolutions of the lower thermosphere under various conditions should be considered carefully in the physics‐based data assimilation system. Additionally, the assessments of the obtained results suggested that the observations of multiple parameters at different altitudes are required to be assimilated into the thermospheric model.
New insights into the radiolytic stability of metal(iv) phosphonate hybrid adsorbent materials
Authors: Luca Vittorio , Veliscek-Carolan Jessica
Published: July 2020

The dependence of radiolytic stability on both the organic and inorganic components of hybrid materials is explained.
Selective aerobic oxidation of sulfides to sulfoxides in water under blue light irradiation over Bi4O5Br2
Authors: Zhao Wei , Yang Chunxia , Huang Jindi , Jin Xiaoli , Deng Yu , Wang Li , Su Fengyun , Xie Haiquan , Wong Po Keung , Ye Liqun
Published: July 2020

A green and practical catalytic system promoted by blue light for oxidation of sulfides to sulfoxides was successfully developed.
Electrochemical dual-aptamer biosensors based on nanostructured multielectrode arrays for the detection of neuronal biomarkers
Authors: Zhang Yuting , Figueroa-Miranda Gabriela , Wu Changtong , Willbold Dieter , Offenhäusser Andreas , Mayer Dirk
Published: July 2020

A dual-aptamer biosensor based on 3D nanostructured gold deposited multielectrode arrays (3D-GMEAs) was developed for the simultaneous detection of AβO and ATP in artificial cerebrospinal fluid.
Fusion of biobased vinylogous urethane vitrimers with distinct mechanical properties
Authors: Chen Fengbiao , Gao Fei , Zhong Jiang , Shen Liang , Lin Yangju
Published: July 2020

The concept of melding two biobased vinylogous urethane vitrimers with distinct mechanical properties has been reported.
A NiCo2S4@N/S–CeO2 composite as an electrocatalytic signal amplification label for aptasensing
Authors: Li Lele , Yang Liwei , Zhang Si , Sun Yuping , Li Fen , Qin Tengteng , Liu Xiaoqiang , Zhou Yanmei , Alwarappan Subbiah
Published: July 2020

Herein, we designed a NiCo2S4@N/S–CeO2 composite with amplified electrocatalytic oxygen reduction (OR) capability by the in situ growth of NiCo2S4 nanoparticles on CeO2 nanospheres with simultaneous doping of nitrogen and sulfur.
The solar abundance problem and eMSTOs in clusters
Authors: Hoppe Richard , Bergemann Maria , Bitsch Bertram , Serenelli Aldo
Published: July 2020

In this study, we focus on the impact of accretion from protoplanetary discs on the stellar evolution of AFG-type stars. We used a simplified disc model that was computed using the Two-Pop-Py code, which contains the growth and drift of dust particles in the protoplanetary disc, to model the accretion scenarios for a range of physical conditions for protoplanetary discs. Two limiting cases were combined with the evolution of stellar convective envelopes that were computed using the Garstec stellar evolution code. We find that the accretion of metal-poor (gas) or metal-rich (dust) material has a significant impact on the chemical composition of the stellar convective envelope. As a consequence, the evolutionary track of the star diverts from the standard scenario predicted by canonical stellar evolution models, which assume a constant and homogeneous chemical composition after the assembly of the star is complete. In the case of the Sun, we find a modest impact on the solar chemical composition. Indeed, the accretion of metal-poor material reduces the overall metallicity of the solar atmosphere and it is consistent, within the uncertainty, with the solar Z reported by Caffau et al. (2011, Sol. Phys., 268, 255), but our model is not consistent with the measurement by Asplund et al. (2009, ARA&A, 47, 481). Another relevant effect is the change of the position of the star in the colour-magnitude diagram. By comparing our predictions with a set of open clusters from the Gaia DR2, we show that it is possible to produce a scatter close to the TO of young clusters that could contribute to explaining the observed scatter in CMDs. Detailed measurements of metallicities and abundances in the nearby open clusters will additionally provide a stringent observational test for our proposed scenario.