bluuebunny/crossref_metadata_2025 huggingface dataset:
On the instability of majority decision-making: testing the implications of the ‘chaos theorems’ in a laboratory experiment
Authors: Sauermann Jan
Published: January 2020

In light of the so-called ‘chaos theorems’ from social choice theory, William Riker (W. H. Freeman and Company, San Francisco, 1982) argues that the indeterminacy of majority rule leads to voting cycles making democratic decisions arbitrary and meaningless. Moreover, when the core is empty, majority instability correlates with the level of conflict among actors. This study uses laboratory committee decision-making experiments to provide an empirical test of both aspects of Riker’s argument. Committees make repeated majority decisions over 20 periods picking points from a two-dimensional policy space. The experiment manipulates committee members’ preferences and thus varies the existence of a core and the level of conflict between group members. The experimental results contradict Riker’s interpretation of the chaos theorems’ implications. Thus, the core exhibits less attraction than generally assumed. Moreover, an empty core is not associated with increased majority rule instability. Instead, conflicting preferences lead to more instability irrespective of the existence of an equilibrium.
Large-scale regionalised LCA shows that plant-based fat spreads have a lower climate, land occupation and water scarcity impact than dairy butter
Authors: Liao Xun , Gerichhausen Monique J. W. , Bengoa Xavier , Rigarlsford Giles , Beverloo Ralph H. , Bruggeman Yvonne , Rossi Vincent
Published: January 2020

Purpose

In light of the sustainable diet debate, we conducted a large-scale regionalised LCA to answer the following questions: (i) does the climate advantage hypothesis of plant-based fat spreads and creams over dairy butter and cream hold regardless of the variabilities of product recipes, geographies and the influence of land use change (LUC)? (ii) Considering the climate-water-land nexus, is there a risk of shifting impacts from climate to water scarcity and land occupation, and what are the key opportunities for impact mitigation?

Methods

A framework for conducting a large-scale regionalised LCA was developed and applied to compare the environmental impacts of 212 plant-based fat spreads, 16 plant-based creams and 40 dairy alternatives sold in 21 countries per 1 kg of product. Data was compiled for different product recipes, key ingredient sourcing countries, production factory locations, energy mixes, packaging designs, transportation and end-of-life scenarios. Spatially (archetype) differentiated agricultural life cycle inventory data were generated, as well as LUC emissions for agricultural ingredients. A total of 18 environmental indicators were assessed.

Results and discussion

All plant-based spreads had a significantly lower climate impact than butter, with and without LUC inclusion. The regionalised analysis highlighted large variabilities across products, ranging from 0.98 to 6.93 (mean 3.3) kg CO2-eq for 212 plant-based spreads and 8.08 to 16.93 (mean 12.1) kg CO2-eq for 21 dairy butter with 95th confidence interval. The main drivers of GHG emissions for plant-based products are oilseed farming and the associated LUC emissions, which can vary significantly depending on type of oilseeds, quantity and sourcing country; in the worst-case scenario, the climate advantage is no longer valid due to LUC. Thus, the inclusion of LUC is essential for a robust assessment and hotspot identification. Overall, the risk of shifting impact was small, as most of the plant-based spreads also had lower impacts for water scarcity footprints and land occupation; 8 of the 212 products were not lower, due to oilseed ingredients with high embodied impacts.

Conclusions

This study confirmed that plant-based spreads had lower climate, water and land impacts than butter, despite variability of product recipes, geographies and influence of LUC. This research offers a framework for performing regionalised agricultural LCA for a large portfolio of products thereby enabling identification of inter-product variabilities and hotspots for the development of mitigation strategies. Key mitigation opportunities include reducing oilseed ingredients’ embodied impacts by optimising product recipe design and adapting supply chain sourcing and agricultural practice.
Customer experience: fundamental premises and implications for research
Authors: Becker Larissa , Jaakkola Elina
Published: January 2020

Customer experience is a key marketing concept, yet the growing number of studies focused on this topic has led to considerable fragmentation and theoretical confusion. To move the field forward, this article develops a set of fundamental premises that reconcile contradictions in research on customer experience and provide integrative guideposts for future research. A systematic review of 136 articles identifies eight literature fields that address customer experience. The article then compares the phenomena and metatheoretical assumptions prevalent in each field to establish a dual classification of research traditions that study customer experience as responses to either (1) managerial stimuli or (2) consumption processes. By analyzing the compatibility of these research traditions through a metatheoretical lens, this investigation derives four fundamental premises of customer experience that are generalizable across settings and contexts. These premises advance the conceptual development of customer experience by defining its core conceptual domain and providing guidelines for further research.
Indoor air pollution and respiratory health effects in inner city children with moderate to severe asthma
Authors: Schachter E. Neil , Rohr Annette , Habre Rima , Koutrakis Petros , Moshier Erin , Nath Amit , Coull Brent , Grunin Avi , Kattan Meyer
Published: January 2020

Indoor air pollution is increasingly recognized as a significant risk for respiratory illness, particularly in vulnerable populations. Thirty-six children aged 6–14 years with moderate/severe asthma from inner city areas in New York City were studied for 2-week periods (summer and winter) using diaries and spirometry. Seven-day integrated indoor samples of PM10, PM2.5, trace elements, elemental/organic carbon, black carbon, and criteria gases (NO2, SO2, and O3) were collected in the subjects’ residences. Asthma outcomes included cough and wheeze severity, albuterol use, and pulmonary function. Mixed effects regression models for longitudinal data were used to relate weekly indoor pollutant concentrations to asthma outcomes. Odds ratios (ORs) were calculated for ordinal outcomes. During winter, significant positive associations for average weekly symptom severity scores were seen for NO2(OR = 2.83;p = 0.02), calcium (OR = 3.29;p = 0.02), and silicon (OR = 3.64;p = 0.04). In summer, chlorine was associated with average weekly symptom scores (OR = 1.85;p = 0.004). Average albuterol puff use per day in winter was associated with NO2(OR = 5.89;p = 0.009), nickel (OR = 2.27;p = 0.05), and silicon (OR = 5.59;p = 0.05). Albuterol use was not associated with indoor pollutants in summer. Asthma severity was associated with specific indoor pollutants. Seasonal differences were observed by pollutant and by clinical index studied.
Probiotics, Nutrition, and the Small Intestine
Authors: Judkins Taylor C. , Archer Douglas L. , Kramer Dean C. , Solch Rebecca J.
Published: January 2020

Purpose of Review

Probiotics are promising remedial treatments for symptoms of small intestine (SI) diseases and promoters of overall good health. Probiotics play an important role in supporting a healthy SI microbiome (eubiosis), and in preventing establishment of unhealthy microbiota. SI eubiosis promotes optimal nutrient uptake, and optimal nutritional status maintains a healthy SI, reducing the likelihood of SI diseases. It is important to understand the advantages and limitations of probiotic therapies.

Recent Findings

Microbial dysbiosis decreases the capacity of the small bowel to utilize and absorb dietary compounds. In some studies, probiotic supplements containing lactic acid bacteria and Bifidobacterium have been demonstrated effective in supporting beneficial microbes in the SI while improving barrier integrity and reducing nutrient malabsorption and SI disease-related pathology.

Strain-specific probiotic therapy may be a natural and effective approach to restoring SI barrier integrity and eubiosis, resulting in improved nutrient absorption and better health, including reducing the incidence of and severity of SI diseases.
The Ethics of Digital Well-Being: A Thematic Review
Authors: Burr Christopher , Taddeo Mariarosaria , Floridi Luciano
Published: January 2020

This article presents the first thematic review of the literature on the ethical issues concerning digital well-being. The term ‘digital well-being’ is used to refer to the impact of digital technologies on what it means to live a life that isgood fora human being. The review explores the existing literature on the ethics of digital well-being, with the goal of mapping the current debate and identifying open questions for future research. The review identifies major issues related to several key social domains: healthcare, education, governance and social development, and media and entertainment. It also highlights three broader themes: positive computing, personalised human–computer interaction, and autonomy and self-determination. The review argues that three themes will be central to ongoing discussions and research by showing how they can be used to identify open questions related to the ethics of digital well-being.
Stability of the formation interface under the impact of hydraulic fracture propagation in the vicinity of the formation interface
Authors: Lu Cong , Lu Yun-Xiao , Guo Jian-Chun , Liu Li-ming
Published: January 2020

Unconventional hydrocarbon reservoirs in layered formations, such as tight sandstones and shales, are continually being developed. Hydraulic fracturing is a critical technology for the high-efficiency development of hydrocarbon reservoirs. Understanding the stress field and stability of the formation interface is vital to understanding stress propagation, preferably before the growing hydraulic fracture contacts the formation interface. In this study, models are developed for computing the stress field of hydraulic fracture propagation near the formation interface, and the stress fields within and at the two sides of the formation interface are analyzed. Four failure modes of the interface under the impact of hydraulic fracture propagation in its vicinity are identified, and the corresponding failure criteria are proposed. By simulating the magnitude and direction of peak stress at different parameters, the failure mode and stability of the formation interface are analyzed. Results reveal that when the interface strength is weak, the formation interface fails before the growing hydraulic fracture contacts it, and its stability is significantly related to a variety of factors, including the type of formation interface, rock mechanical properties, far-field stress, structural parameters, distance between the hydraulic fracture and formation interface, and fracturing execution parameters.
Chronic Pancreatitis—Update on Pathophysiology and Therapeutic Approaches
Authors: J. C. Chris , Parks Rowan W.
Published: January 2020

Chronic pancreatitis is an inflammatory condition characterized by structural change within the pancreas, that leads to progressive and irreversible loss of functioning pancreatic parenchyma, exocrine/endocrine dysfunction and an increased risk of pancreatic ductal adenocarcinoma. Whilst hallmarks of advanced disease are readily identifiable on routine clinical imaging, concordance between structural changes within the pancreas and symptoms is poor, such that early diagnosis can be challenging. Traditionally, chronic pancreatitis has been managed with a ‘step-up’ approach of measures including analgesia, therapeutic endoscopy and surgery (in a select minority of patients). Accumulating evidence is emerging to challenge this approach: early surgical intervention may offer the opportunity to interrupt the disease process before irreversible sequelae become established. This article provides an overview of the pathophysiology underlying chronic pancreatitis together with a review of the current evidence to support established and novel therapeutic approaches to the disease.
Lumped-Parameter Circuit Platform for Simulating Typical Cases of Pulmonary Hypertensions from Point of Hemodynamics
Authors: Tang Hong , Dai Ziyin , Wang Miao , Guo Binbin , Wang Shunyu , Wen Jiabin , Li Ting
Published: January 2020

Pulmonary hypertension (PH) presents unusual hemodynamic states characterized by abnormal high blood pressure in pulmonary artery. The objective of this study is to simulate how the hemodynamics develops in typical PH cases without treatment. A lumped-parameter circuit platform of human circulation system is set up to simulate hemodynamic abnormalities of PH in different etiologies and pathogenesis. Four typical cases are considered, which are distal pulmonary artery stenosis, left ventricular diastolic dysfunction, ventricular septal defect, and mitral stenosis. The authors propose regulation laws for chambers and vessels to adapt the abnormal hemodynamic conditions for each PH case. The occurrence and development of each PH case are simulated over time using the lumped-parameter circuit platform. The blood pressure, blood flow, pressure-volume relations for chambers and vessels are numerically calculated for each case of PH progression. The model results could be a quite helpful to understand the hemodynamic mechanism of typical PHs.
Biosorption of copper(II) onto spent biomass of Gelidiella acerosa (brown marine algae): optimization and kinetic studies
Authors: Dulla John Babu , Tamana Mohan Rao , Boddu Sumalatha , Pulipati King , Srirama Krupanidhi
Published: January 2020

This study exclusively focused on the potential application of an inexpensive and sustainable waste macro-algal biomass as an adsorbent for biosorption of copper ions from aqueous medium. After extraction of agar from brown macro-marine algaeGelidiella acerosa, the residual biomass without any further treatment was used as an adsorbent for the expulsion of copper from wastewater. Physicochemical parameters of biosorption like initial pH, initial concentration of Cu(II) solution and biosorbent dosage were optimized using response surface methodology. The maximum copper biosorption potential of 96.36% was observed at optimum conditions of pH of 5.31, initial concentration of 23.87 mg/l and biosorbent dosage of 0.41 g/l. Adopting FTIR and SEM techniques, the surface morphological features of biosorbent were studied. The pseudo-second-order kinetic model was found to be a proper approach to describe biosorption kinetics. All these results confirmed that spentG.acerosacould be considered as an efficient, eco-friendly and economic alternative for Cu(II) removal from aqueous solution.
Characterization of Altered Mica From Sokli, Northern Finland
Authors: Rama M. , Eklund O. , Fröjdö S. , Smått J.-H. , Lastusaari M. , Laiho T.
Published: January 2020

Vermiculite is a mineral with many potential uses in various industrial areas, such as in insulation, horticulture, and environmental applications. The regolith of the Sokli carbonatite intrusion in northern Finland consists of weathered micas which reportedly contain vermiculite. The aim of the present study was to characterize the weathered mica in order to determine if the weathered regolith contains vermiculite. If so, the value of the apatite-rich Sokli intrusion may increase, because the vermiculite could be classified as an ore in Sokli. For the characterization, mica fractions were investigated using electron probe microanalysis (EPMA), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The EPMA results show that the potassium (K2O) content of the mica investigated varies between 6.20 and 0.31 wt.%. The XRD results provided evidence that the interlayer distances in the mica vary between 10.1 and 14.7 Å. The TGA shows that the dehydration of the samples varies between 6 and 12 wt.% for temperatures up to 170°C. Dehydroxylation takes place in three steps, as is characteristic for vermiculite. The results from this study revealed that mica in the weathered parts of the Sokli carbonatite is mostly vermiculite, and that the vermiculite was formed by the weathering of phlogopite. These results can be used to determine whether vermiculite is a possible future commodity at the Sokli carbonatite complex.
Assessment of current rotor design comparison practices based on high-fidelity CFD methods
Authors: Fitzgibbon T. , Woodgate M. , Barakos G.
Published: January 2020

This paper provides an assessment of current rotor design comparison practices. First, the employed CFD method is validated for a number of rotor designs and is shown to achieve accurate performance predictions in hover and high-speed forward flight. Based on CFD results, a detailed investigation is performed in terms of comparing different rotor designs. The CFD analysis highlighted the need of high fidelity methods due to the subtle aerodynamics involved in advanced planforms. Nevertheless, the paper suggests that the correct basis for comparison in terms of performance metrics must be used to inform decisions about the suitability of the rotor blades designs for specific applications. In particular, when comparing blades of advanced planforms, direct torque and thrust comparisons are better than the commonly used lift to drag ratio and figure of merit.
Parenting style, coping efficacy, and risk-taking behavior in Chinese young adults
Authors: Ju Chengting , Wu Rina , Zhang Baoshan , You Xuqun , Luo Yun
Published: January 2020

The goal of this study was to examine the relationship between three parenting styles (warmth, rejection, and overprotection), coping efficacy and risk-taking behavior in Chinese young adults. A total of 719 subjects completed three instruments: the Egna Minneu av Bardndosnauppforstran, the Coping Efficacy Questionnaire and the Adolescent Risk-Taking Questionnaire. Structural equation modeling results showed that maternal warmth (negatively) and rejection (positively), but not overprotection, correlated with risk-taking behavior via coping efficacy, whereas paternal rejection and overprotection (positively), but not warmth, correlated with risk-taking behavior via coping efficacy. These results suggest that parenting styles indirectly associate with risk-taking behavior through coping efficacy in young adults.
New constraints from U–Pb dating of detrital zircons on the palaeogeographic origin of metasediments in the Talea Ori, central Crete
Authors: Seybold Lina , Dörr Wolfgang , Trepmann Claudia A. , Krahl Jochen
Published: January 2020

High-pressure low-temperature metamorphic sediments of the Phyllite–Quartzite unitsensu strictoand the Talea Ori group are investigated in the field, microstructurally and by U–Pb dating of detrital zircons to shed light on their palaeogeographic origin. Zircon age spectra with ages >450 Ma of the Phyllite–Quartzite unitsensu strictoindicate a palaeogeographic origin at the northern margin of East Gondwana. In contrast, the lower stratigraphic, siliciclastic formations of the Talea Ori group show a high number of well-rounded Cambrian to Early Carboniferous aged zircons and a Neoproterozoic zircon age spectrum with East Gondwana affinity. Based on the comparison of zircon age data, a possible distal sediment source is the Sakarya Zone at the southern active margin of Eurasia. To reconcile the zircon data with the geological observations we propose different alternative models, or a combination of these, including sediment transport from the Sakarya Zone and/or a westerly source towards the northern margin of Gondwana as well as terrane-displacement of the Sakarya Zone. Also, a palaeogeographic origin of the Talea Ori group at the southern active margin of Eurasia cannot be excluded. This alternative, however, would not be consistent with the usually assumed association of the Talea Ori group with the Plattenkalk unit characterized by a palaeogeographic origin at the northern margin of Gondwana.
Financial Flexibility: At What Cost?
Authors: Garmaise Mark J. , Natividad Gabriel
Published: January 2020

Firms strategically borrow in different locations. Approximately one-quarter of Peruvian companies with operations in multiple areas source their financing from more than one province. Mining windfalls generate finance supply shocks, leading to the provision of more credit at lower average rates, and we show that firms exploit geographic financial flexibility by concentrating their borrowing in booming locations. Firms are less likely to initiate borrowing in new markets when their current borrowing provinces are thriving. The pursuit of flexibility in borrowing markets, however, degrades a firm’s relationships with its existing lenders, thereby heightening its risk of future financial distress.
Differential forms for plasma physics
Authors: MacKay R. S.
Published: January 2020

Differential forms provide a coordinate-free way to express many quantities and relations in mathematical physics. In particular, they are useful in plasma physics. This tutorial gives a guide so that you can read the plasma physics literature that uses them and apply them yourself.
Anti-gambling policies: framing morality policy in Italy
Authors: Bassoli Matteo , Marzulli Michele , Pedroni Marco
Published: January 2020

Recent research on morality policy has focused on policy change, morality framing and the presence of favourable cultural opportunity structures (COSs). The resulting literature describing various aspects of morality policy has failed to discuss the impact of multilevel dynamic in this field. This contribution examines gambling policy in Italy, applying a multilevel approach to detect the presence of favourable COSs, and whether policymakers frame policies morally. Italy offers a particularly fertile field for the study of morality policy, featuring a liberal national approach versus local restrictive policy. By applying a methodology based on semistructured interviews and secondary sources, we examine the national and local political spheres, demonstrating that morality framing, when detected, is more likely to be found at the local level where the influence of experts and interest groups on legislators may result in the transformation of a health policy based on paternalistic considerations.
Revisiting Leighton’s theorem with the Haar measure
Authors: WOODHOUSE DANIEL J.
Published: January 2020

Leighton’s graph covering theorem states that a pair of finite graphs with isomorphic universal covers have a common finite cover. We provide a new proof of Leighton’s theorem that allows generalisations; we prove the corresponding result for graphs with fins. As a corollary we obtain pattern rigidity for free groups with line patterns, building on the work of Cashen–Macura and Hagen–Touikan. To illustrate the potential for future applications, we give a quasi-isometric rigidity result for a family of cyclic doubles of free groups.
FACTORIZING MULTILINEAR KERNEL OPERATORS THROUGH SPACES OF VECTOR MEASURES
Authors: GALDAMES-BRAVO ORLANDO
Published: January 2020

We consider a multilinear kernel operator between Banach function spaces over finite measures and suitable order continuity properties, namely $T:X_{1}(\,\unicode[STIX]{x1D707}_{1})\times \cdots \times X_{n}(\,\unicode[STIX]{x1D707}_{n})\rightarrow Y(\,\unicode[STIX]{x1D707}_{0})$. Then we define, via duality, a class of linear operators associated to the $j$-transpose operators. We show that, under certain conditions of $p$th power factorability of such operators, there exist vector measures $m_{j}$ for $j=0,1,\ldots ,n$ so that $T$ factors through a multilinear operator $\widetilde{T}:L^{p_{1}}(m_{1})\times \cdots \times L^{p_{n}}(m_{n})\rightarrow L^{p_{0}^{\prime }}(m_{0})^{\ast }$, provided that $1/p_{0}=1/p_{1}+\cdots +1/p_{n}$. We apply this scheme to the study of the class of multilinear Calderón–Zygmund operators and provide some concrete examples for the homogeneous polynomial and multilinear Volterra and Laplace operators.
Unified Picture of Chemical Differentiation in Disk-Forming Regions of Low-Mass Protostellar Sources
Authors: Oya Yoko
Published: January 2020

Young low-mass protostellar sources are known to show significant chemical diversity in their envelopes at a few 1000s au scale; two distinct cases are hot corino chemistry and warm carbon-chain chemistry (WCCC). It is of great interest how the chemical diversity is inherited to chemistry of disk-forming regions. With the recent ALMA observations, we found that the chemical diversity in envelopes is indeed delivered into the disk-forming regions at a 100 au scale. Moreover, the chemical composition changes drastically from envelopes to disks. We also found sources with the hybrid chemical characteristics; both hot corino chemistry and WCCC occur in spatially separated parts of a single source. This hybrid case may be a common occurrence, while hot corinos and WCCC sources are regarded as distinct cases. This unified view of chemistry in disk-forming regions will be an important clue to tracing the chemical evolution from protostellar cores to protoplanetary disks.
Star Clusters Triggered by GS242-03+37
Authors: Palouš Jan , Ehlerová Soňa
Published: January 2020

We explore the Milky Way supershell GS242-03+37. We argue that the observed HI distribution can be explained as an expanding structure about 100 Myr old powered with a modest energy released by an OB association. The formation of star clusters has been triggered less than 30 Myr ago when the ISM density in the supershell increased due to the galactic differential rotation. The observed age sequence of young star clusters is related to the evolution of the column density during the supershell expansion.
Star formation in cloud cores — simulations and observations of dense molecular cores and the formation of solar mass stars
Authors: Federrath C.
Published: January 2020

Star formation is inefficient. Recent advances in numerical simulations and theoretical models of molecular clouds show that the combined effects of interstellar turbulence, magnetic fields and stellar feedback can explain the low efficiency of star formation. The star formation rate is highly sensitive to the driving mode of the turbulence. Solenoidal driving may be more important in the Central Molecular Zone, compared to more compressive driving agents in spiral-am clouds. Both theoretical and observational efforts are underway to determine the dominant driving mode of turbulence in different Galactic environments. New observations with ALMA, combined with other instruments such as CARMA, JCMT and the SMA begin to reveal the magnetic field structure of dense cores and protostellar disks, showing highly complex field geometries with ordered and turbulent field components. Such complex magnetic fields can give rise to a range of stellar masses and jet/outflow efficiencies in dense cores and protostellar accretion disks.
3D radiation MHD simulations of gas and dust in protoplanetary disks
Authors: Flock Mario
Published: January 2020

3D global radiation MHD simulations of gas and dust in protoplanetary disks allow us to understand the dynamical and thermal evolution of protoplanetary disks. At the same time, recent observations in the mm-dust emission by the Atacama Large Millimeter Array (ALMA) allow us to resolve structures at scales of the disk scale height.

From our recent simulation results by Flock et al. (2015) and Flock et al. (2017) we are able to directly compare for the first time detailed observational constraints from high-resolution observations by ALMA with the gas and dust dynamics obtain in 3D state-of-art simulations of protoplanetary disks. Especially measurements of the dust scale height obtained from the disk around the young system HL Tau allow us to compare for different gas disk instability models. Further we use Monte Carlo radiation transfer models of the dusty disk to compare our results of the dust scale height in 3D radiation HD and MHD simulations. Our findings are that magnetized models fit perfectly the observational constraints, showing a strongly settled disk, while hydrodynamical turbulence leads to a dust uplifting which is larger than expected. These results open a new window to compare future multi-wavelength observations to simulations.
Chemical modeling of FU Ori protoplanetary disks
Authors: Molyarova Tamara , Akimkin Vitaly , Semenov Dmitry , Ábrahám Péter , Henning Thomas , Kóspál Ágnes , Vorobyov Eduard , Wiebe Dmitri
Published: January 2020

Luminosity outbursts of the FU Ori type stars, which have a magnitude of ∼ 100 L⊙ and last for decades, may affect chemical composition of the surrounding protoplanetary disk. Using astrochemical modelling we analyse the changes induced by the outburst and search for species sensitive to the luminosity rise. Some changes in the disk molecular composition appear not only during the outburst itself but can also retain for decades after the end of the outburst. We analyse main chemical processes responsible for these effects and assess timescales at which chemically inert species return to the pre-outburst abundances.
Formation and Evolution of Protoplanetary Disks: Observations and Modeling of Jets, Disks, and Disk Substructures
Authors: Pérez Laura M.
Published: January 2020

Planet formation takes place in the gaseous and dusty disks that surround young stars, known as protoplanetary disks. With the advent of sensitive observations and together with developments in theory, our field is making rapid progress in understanding how the evolution of protoplanetary disks takes place, from its inception to the end result of a fully-formed planetary system. In this review, I discuss how observations that trace both the dust and gas components of these systems inform us about their evolution, mass budget, and chemistry. Particularly, the process of disk evolution and planet formation will leave an imprint on the distribution of solid particles at different locations in a protoplanetary disk, and I focus on recent observational results at high angular resolution in the sub-millimeter regime, which have revealed a variety of substructures present in these objects.
Distance to health services and treatment-seeking for depressive symptoms in rural India: a repeated cross-sectional study
Authors: Roberts T. , Shiode S. , Grundy C. , Patel V. , Shidhaye R. , Rathod S. D.
Published: January 2020

Aims

Research from high-income countries has implicated travel distance to mental health services as an important factor influencing treatment-seeking for mental disorders. This study aimed to test the extent to which travel distance to the nearest depression treatment provider is associated with treatment-seeking for depression in rural India.

Methods

We used data from a population-based survey of adults with probable depression (n = 568), and calculated travel distance from households to the nearest public depression treatment provider with network analysis using Geographic Information Systems (GIS). We tested the association between travel distance to the nearest public depression treatment provider and 12 month self-reported use of services for depression.

Results

We found no association between travel distance and the probability of seeking treatment for depression (OR 1.00, 95% CI 0.98–1.02, p = 0.78). Those living in the immediate vicinity of public depression treatment providers were just as unlikely to seek treatment as those living 20 km or more away by road. There was evidence of interaction effects by caste, employment status and perceived need for health care, but these effect sizes were generally small.

Conclusions

Geographic accessibility – as measured by travel distance – is not the primary barrier to seeking treatment for depression in rural India. Reducing travel distance to public mental health services will not of itself reduce the depression treatment gap for depression, at least in this setting, and decisions about the best platform to deliver mental health services should not be made on this basis.
Cover crop response to residual herbicides in peanut-cotton rotation
Authors: Price Katilyn J. , Li Xiao , Price Andrew
Published: January 2020

Cover crops can provide many benefits to peanut and cotton crops planted in rotation including suppressing weeds, conserving soil moisture after termination, increasing soil organic matter, and reducing soil erosion. However, herbicide carryover can affect cover crop establishment. The objective of this study was to investigate the responses of 6 cover crops (daikon radish, cereal rye, oat, crimson clover, winter wheat, and common vetch) to 12 soil residual herbicides. A multiyear (2016–2018), multilocation study was conducted in Macon and Henry counties, Alabama. Herbicide treatments included S-metolachlor, acetochlor, pyroxasulfone, diclosulam, imazapic, chlorimuron-ethyl, bentazon plus acifluorfen, pyrithiobac-sodium, trifloxysulfuron-sodium, diuron, prometryn, and flumioxazin, each applied at 10% of the full-labeled rate. At 42 to 52 and 145 to 149 d after planting (DAP), cover crop plant heights and stand counts were evaluated, as was biomass at 145 to 149 DAP. Treatments varied from year to year but not locations. In 2016, significant stand reductions (P ≤ 0.10) of 36% to 43% in rye and 44% to 75% in wheat were observed at 48 to 52 DAP for S-metolachlor, acetochlor, pyroxasulfone, imazapic, and bentazon plus acifluorfen compared with nontreated plants. Vetch had stand reductions ranging from 14% to 80% for all treatments 50 DAP except for plants treated with prometryn. S-metolachlor, pyroxasulfone, and acetochlor reduced stands of rye, wheat, and vetch more than any other herbicides. In 2017, at 147 to 149 DAP, clover stands were reduced by 29% with diclosulam and by 38% with trifloxysulfuron-sodium. Similarly, radish stands were reduced by 64% with diclosulam treatment. No significant biomass reductions were observed for any cover crop species either year. Oat showed the most tolerance with no treatments reducing any growth parameters either year. Although initial injury and stunting may occur, biomass at termination of cover crops were not affected by herbicide residues evaluated in this study.
Differences in efficacy, resistance mechanism and target protein interaction between two PPO inhibitors in Palmer amaranth (Amaranthus palmeri)
Authors: Wu Chenxi , Goldsmith Michael-Rock , Pawlak John , Feng Paul , Smith Stacie , Navarro Santiago , Perez-Jones Alejandro
Published: January 2020

A weed survey was conducted on 134 Palmer amaranth (Amaranthus palmeri S. Watson) populations from Mississippi and Arkansas in 2017 to investigate the spread of resistance to protoporphyrinogen oxidase (PPO) inhibitors using fomesafen as a proxy. Fomesafen resistance was found in 42% of the A. palmeri populations. To investigate the resistance basis of different PPO inhibitors, we further characterized 10 representative populations by in planta bioassay in a controlled environment and molecular characterizations (DNA sequencing and TaqMan® gene expression assay). A total of 160 plants were sprayed with a labeled field rate (1X) of fomesafen or salfufenacil and screened for the presence of three known resistance-endowing mutations in the mitochondrial PPX2 gene (ΔGly-210, Arg-128-Gly, Gly-399-Ala). To compare the potencies of fomesafen and saflufenacil, dose–response studies were conducted on two highly resistant and one sensitive populations. The interaction of the two herbicides with the target protein harboring known PPX2 mutations was also analyzed. Our results showed that: (1) 90% of the fomesafen- or saflufenacil-resistant plants have at least one of the three known PPX2 mutations, with ΔGly-210 being the most prevalent; (2) saflufenacil is more potent than fomesafen, with five to nine times lower resistance/susceptible (R/S) ratios; (3) fomesafen selects for more diverse mutations, and computational inhibitor/target modeling of fomesafen suggest a weaker binding affinity in addition to a smaller interaction volume and volume overlap with the substrate protoporphyrinogen IX than saflufenacil. As a result, saflufenacil shows reduced sensitivity to PPX2 target-site mutations. Results from current study can help pave the way for designing weed management strategies to delay resistance development and maintain the efficacy of PPO inhibitors.
New Approaches to Identifying and Reducing the Global Burden of Disease From Pollution
Authors: Filippelli Gabriel , Anenberg Susan , Taylor Mark , van Geen Alexander , Khreis Haneen
Published: January 2020

Pollution from multiple sources causes significant disease and death worldwide. Some sources are legacy, such as heavy metals accumulated in soils, and some are current, such as particulate matter. Because the global burden of disease from pollution is so high, it is important to identify legacy and current sources and to develop and implement effective techniques to reduce human exposure. But many limitations exist in our understanding of the distribution and transport processes of pollutants themselves, as well as the complicated overprint of human behavior and susceptibility.

New approaches are being developed to identify and eliminate pollution in multiple environments. Community‐scale detection of geogenic arsenic and fluoride in Bangladesh is helping to map the distribution of these harmful elements in drinking water. Biosensors such as bees and their honey are being used to measure heavy metal contamination in cities such as Vancouver and Sydney. Drone‐based remote sensors are being used to map metal hot spots in soils from former mining regions in Zambia and Mozambique. The explosion of low‐cost air monitors has allowed researchers to build dense air quality sensing networks to capture ephemeral and local releases of harmful materials, building on other developments in personal exposure sensing. And citizen science is helping communities without adequate resources measure their own environments and in this way gain agency in controlling local pollution exposure sources and/or alerting authorities to environmental hazards. The future of GeoHealth will depend on building on these developments and others to protect a growing population from multiple pollution exposure risks.
Testing Models of Cenozoic Exhumation in the Western Greater Caucasus
Authors: Vincent Stephen J. , Somin Mark L. , Carter Andrew , Vezzoli Giovanni , Fox Matthew , Vautravers Benoit
Published: January 2020

The Greater Caucasus form the northernmost deformation front of the Arabia‐Eurasia collision zone. Earlier thermochronometric studies on the crystalline core of the western Greater Caucasus highlighted an abrupt along‐strike increase in cooling ages to the west of Mt. Elbrus. Twenty‐eight thermochronometric analyses conducted as part of this study confirm this pattern. Overall Cenozoic exhumation was restricted to less than 5–7 km, with slow to moderate punctuated Oligo‐Miocene cooling. Cooling rates increased during the Late Miocene to Pliocene. These are most rapid east of Mt. Elbrus, where they probably increased later than farther west (at c. 5 Ma rather than 10–8 Ma). Differential cooling rates do not appear to be driven by lateral variations in tectonic shortening. The region undergoing rapid young cooling does coincide, however, with an area of mantle‐sourced Late Miocene and younger magmatism. Thermal relaxation or overprinting is ruled out because geomorphic and modern sediment flux data mirror the thermochronometric trends. The buoyancy effects of demonstrable mantle upwelling are capable of causing the magnitude of exhumation‐related cooling recorded in this study, but typically act over wavelengths of several 100 km. We suggest that lithospheric heterogeneities are responsible for modulating the shorter wavelength differences in exhumation rate documented here. These heterogeneities may include the continuation of the same structures responsible for the eastern margin of the Stavropol High to the north of the Caucasus, although further work is required. Similar abrupt variations in mantle‐supported uplift and exhumation modulated by crustal structure may occur in other mountain belts worldwide.
Transport of Pseudomonas aeruginosa in Porous Media Mediated by Low‐Concentration Surfactants: The Critical Role of Surfactant to Change Cell Surface Hydrophobicity
Authors: Liu Guansheng , Fang Zhendong , Zhong Hua , Shi Liangsheng , Yang Xin , Liu Zhifeng
Published: January 2020

Transport of P. aeruginosa ATCC 9027 in quartz sands mediated by low‐concentration surfactants of sodium dodecyl benzene sulfonate (SDBS) or Triton X‐100 was investigated with column experiments. P. aeruginosa ATCC 9027 was cultured with glucose and hexadecane to produce cells with different initial cell surface hydrophobicity (CSH). Transport behavior of cells was characterized by breakthrough curves (BTCs) and deposition rate coefficients (kd) values were estimated by fitting the BTCs using colloid transport models. Relations between kd and CSH represented by bacterial‐adsorption‐to‐hydrocarbon fraction (BATH fraction) and between kd and cell surface charge represented by zeta potential were analyzed to quantitatively describe the effect of surfactants on cell transport. Results showed that at low concentrations the ionic SDBS increased cell surface charge while the nonionic Triton X‐100 had no effect, while both of them caused significant differentiation of CSH. The kinetic attachment‐detachment model with blocking was the best among the five models tested to fit BTCs and low‐concentration SDBS and Triton X‐100 caused remarkable change of kd. A good linear relation between kd and cell BATH fraction was observed (R2 = 0.82), whereas the linearity between kd and total zeta potential of cell and sand was poor (R2 = 0.11). The data reconstructed from our previous studies showed that the linearity between kd and cell BATH fraction also presented in sands and glass beads for low‐concentration rhamnolipid biosurfactant. In all, these results showed that CSH plays a critical role in cell transport in porous media and changing CSH is a common mechanism for low‐concentration surfactants to mediate the transport, which implies the potential of using low‐concentration surfactants to regulate bacterial transport for bioaugmentation.
Adverse birth outcomes in adolescent and young adult female cancer survivors: a nationwide population-based study
Authors: Kao Wei-Heng , Kuo Chang-Fu , Chiou Meng-Jiun , Liu Yu-Cheng , Wang Chun-Chieh , Hong Ji-Hong , Hsu Jun-Te , Chiang Yu-Jung , Chuang Yi-Fang
Published: January 2020

Background

For female adolescent and young adult (AYA), cancer with treatments may affect their children’s health. Our aim was to determine reliable risk estimates of adverse birth outcomes in AYA cancer survivors and the differential effects of treatments.

Methods

The study population of 4547 births in the AYA cancer survivor group and 45,463 in the comparison group were identified from two national databases between 2004 and 2014. Detailed maternal health conditions, such as maternal comorbidities, medication use during pregnancy and lifestyles, were adjusted in the statistical analyses. The outcomes included low birth weight, preterm labour, stillbirth, small or large for gestational age, a 5-min Apgar score <7, congenital malformation and foetal distress.

Results

The AYA cancer survivor group had a 9% higher risk of overall adverse birth outcomes (adjusted odds ratio, 1.09; 95% confidence interval, 1.02–1.16), especially low birth weight and preterm labour than the comparison group. The radiotherapy-only group additionally had a higher risk of foetal distress, and a 5-min Apgar score <7.

Conclusion

AYA cancer survivors, especially those who have received radiotherapy, still have higher risks of adverse birth outcomes after adjusting for detailed maternal health conditions. Preconception counselling and additional surveillance may be warranted in this population.
Inhibition of thyroid hormone signaling protects retinal pigment epithelium and photoreceptors from cell death in a mouse model of age-related macular degeneration
Authors: Ma Hongwei , Yang Fan , Ding Xi-Qin
Published: January 2020

Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly. Dry AMD is characterized by a progressive macular degeneration of the retinal pigment epithelium (RPE) and photoreceptors, and the RPE oxidative damage/dystrophy is at the core of the disease. Recent population/patients-based studies have shown an association of high free serum thyroid hormone (TH) levels with increased risk of AMD. This work investigated the effects of TH signaling inhibition on RPE and photoreceptor damage/cell death in an oxidative stress-induced mouse model of AMD. TH signaling inhibition was achieved by anti-thyroid drug treatment and oxidative stress was induced by sodium iodate (NaIO3) administration. Mice treated with NaIO3 showed severe RPE and photoreceptor cell death/necroptosis, destruction, oxidative damage, retinal stress, and reduced retinal function. Treatment with anti-thyroid drug protected RPE and photoreceptors from damage/cell death induced by NaIO3, reduced oxidative damage of RPE and photoreceptors, and preserved retinal function. Gene expression analysis showed that the NaIO3-induced RPE/photoreceptor damage/cell death involves multiple mechanisms, including cellular oxidative stress responses, activation of necroptosis/apoptosis signaling, and inflammatory responses. Treatment with anti-thyroid drug abolished these cellular stress/death responses. The findings of this study demonstrate a role of TH signaling in RPE and photoreceptor cell death after oxidative stress challenge, and support a role of TH signaling in the pathogenesis of AMD.
Sestrin prevents atrophy of disused and aging muscles by integrating anabolic and catabolic signals
Authors: Segalés Jessica , Perdiguero Eusebio , Serrano Antonio L. , Sousa-Victor Pedro , Ortet Laura , Jardí Mercè , Budanov Andrei V. , Garcia-Prat Laura , Sandri Marco , Thomson David M. , Karin Michael , Hee Lee Jun , Muñoz-Cánoves Pura
Published: January 2020

A unique property of skeletal muscle is its ability to adapt its mass to changes in activity. Inactivity, as in disuse or aging, causes atrophy, the loss of muscle mass and strength, leading to physical incapacity and poor quality of life. Here, through a combination of transcriptomics and transgenesis, we identify sestrins, a family of stress-inducible metabolic regulators, as protective factors against muscle wasting. Sestrin expression decreases during inactivity and its genetic deficiency exacerbates muscle wasting; conversely, sestrin overexpression suffices to prevent atrophy. This protection occurs through mTORC1 inhibition, which upregulates autophagy, and AKT activation, which in turn inhibits FoxO-regulated ubiquitin–proteasome-mediated proteolysis. This study reveals sestrin as a central integrator of anabolic and degradative pathways preventing muscle wasting. Since sestrin also protected muscles against aging-induced atrophy, our findings have implications for sarcopenia.