bluuebunny/crossref_metadata_2025 huggingface dataset:
Aerodynamic benefits for a cyclist by drafting behind a motorcycle
Authors: Blocken Bert , Malizia Fabio , van Druenen Thijs , Gillmeier Stefanie
Published: September 2020

Motorcycles are present in cycling races for reasons including television broadcasting. During parts of the race, these motorcycles ride in front of individual or groups of cyclists. Concerns have been expressed in the professional cycling community that these motorcycles can provide aerodynamic benefits in terms of drag reduction for the cyclists drafting behind them. However, to the best of our knowledge, no information about the extent of these benefits is present in the scientific literature. Therefore, this paper analyses the potential drag reduction for a cyclist by drafting behind a motorcycle. Wind tunnel measurements and numerical simulations with computational fluid dynamics were performed. It was shown that drafting at separation distances d = 2.64, 10, 30 and 50 m can reduce the drag of the cyclist down to 52, 77, 88 and 93% of that of an isolated cyclist, respectively. A cyclist power model is used to convert these drag reductions into potential time gains. For a non-drafting cyclist at a speed of 54 km/h on level road in calm weather, the time gains by drafting at d = 2.64, 10, 30 and 50 m are 12.7, 5.4, 2.7 and 1.6 s per km, respectively. These time differences can influence the outcome of cycling races. The current rules of the International Cycling Union do not prevent these aerodynamic benefits from occurring in races.
Effect of starting materials and sintering temperature on microstructure and optical properties of Y2O3:Yb3+ 5 at% transparent ceramics
Authors: Yavetskiy R. P. , Balabanov A. E. , Parkhomenko S. V. , Kryzhanovska O. S. , Doroshenko A. G. , Mateychenko P. V. , Tolmachev A. V. , Li Jiang , Jiang Nan , Gheorghe L. , Enculescu M.
Published: September 2020

Y2O3:Yb3+ 5 at% ceramics have been synthesized by the reactive sintering method using different commercial yttria powders (Alfa-Micro, Alfa-Nano, and ITO-V) as raw materials. It has been shown that all Y2O3 starting powders consist from agglomerates up to 5–7 µm in size which are formed from 25–60 nm primary particles. High-energy ball milling allows to significantly decreasing the median particle size D50 below 500 nm regardless of the commercial powders used. Sintering experiments indicate that powder mixtures fabricated from Alfa-Nano yttria powders have the highest sintering activity, while (Y0.86La0.09Yb0.05)2O3 ceramics sintered at 1750 °C for 10 h are characterized by the highest transmittance of about 45%. Y2O3:Yb3+ ceramics have been obtained by the reactive sintering at 1750–1825°C using Alfa-Nano Y2O3 powders and La2O3+ZrO2 as a complex sintering aid. The effects of the sintering temperature on densification processes, microstructure, and optical properties of Y2O3:Yb3+ 5 at% ceramics have been studied. It has been shown that Zr4+ ions decrease the grain growth of Y2O3:Yb3+ ceramics for sintering temperatures 1750–1775 °C. Further increasing the sintering temperature was accompanied by a sharp increase of the average grain size of ceramics referred to changes of structure and chemical composition of grain boundaries, as well as their mobility. It has been determined that the optimal sintering temperature to produce high-dense yttria ceramics with transmittance of 79%–83% and average grain size of 8 µm is 1800 °C. Finally, laser emission at ∼1030.7 nm with a slope efficiency of 10% was obtained with the most transparent Y2O3:Yb3+ 5 at% ceramics sintered.
A comprehensive study on Li4Si1−xTixO4 ceramics for advanced tritium breeders
Authors: Gong Yichao , Liu Lin , Qi Jianqi , Yang Mao , Li Junjie , Wang Hailiang , Guo Hao , Zhang Guojun , Lu Tiecheng
Published: September 2020

Hetero-element doped lithium orthosilicates have been considered as advanced tritium breeders due to the superior performances. In this work, Li4Si1−xTixO4 ceramics were prepared by proprietary hydrothermal process and multistage reactive sintering. The reaction mechanism of Li4Si1−xTixO4 was put forward. XRD and SEM analyses indicate that insertion of Ti leads to lattice expansion, which promotes the grain growth and changes the fracture mode. The compressive tests show that the crush load increases almost four times by increasing x from 0 to 0.2. However, the thermal conductivity and ionic conductivity are the best when x = 0.05 and x = 0.1, respectively. Thermal cycling stability of Li4Si1−xTixO4 pebbles was further appraised through investigating the changes of microstructure and crush load. After undergoing thermal cycling, the Li4Si1−xTixO4 still show higher crush load compared with Li4SiO4, despite Ti segregation in some samples. The x = 0.05 sample exhibits excellent thermal cycling stability. In summary, proper amount of Ti doping can improve the crush load, thermal and ionic conductivity, and thermal cycling stability of Li4SiO4.
Precise Formation-Flying Telescope in Target-Centric Orbit: the Solar Case
Authors: Saint-Hilaire Pascal , Marchese Jeffrey E.
Published: September 2020

We present the general concept of a telescope with optics and detectors mounted on two separate spacecrafts, in orbit around the telescope’s target (scopocentric or target-centric orbit), and using propulsion to maintain the Target-Optics-Detector alignment and Optics-Detector distance. Specifically, we study the case of such a telescope with the Sun as the target, orbiting at $\sim $
∼
1 AU. We present a simple differential acceleration budget for maintaining Target-Optics-Detector alignment and Optics-Detector distance, backed by simulations of the orbital dynamics, including solar radiation pressure and influence of the planets. Of prime interest are heliocentric orbits (such as Earth-trailing/leading orbits or Distant Retrograde Orbits), where thrust requirement to maintain formation is primarily in a single direction (either sunward or anti-sunward), can be quite minuscule (a few m/s/year), and preferably met by constant-thrust engines such as solar electric propulsion or even by solar sailing via simple extendable and/or orientable flaps or rudders.
Geometry to Build Models, Models to Visualize Geometry
Authors: Cumino Caterina , Pavignano Martino , Spreafico Maria L. , Zich Ursula
Published: September 2020

In the seventeenth century, Guarino Guarini, mathematician and architect, affirmed that architecture, a discipline that primarily deals with measures, relies on geometry: therefore, the architect needs to know at least its basic principles. On behalf of Guarini’s words, we designed a set of interdisciplinary teaching experiences, between mathematics (via a calculus course) and drawing (via our Architectural Drawing and Survey Laboratory courses) that we proposed to first-year under graduate students studying for an Architecture degree. The tasks concern mathematical and representational issues about vaulted roofing systems and are based on the use of physical models in conjunction with digital tools, in order to make the cognitive geometric process more effective, thus following a consolidated tradition of both disciplines.
Prognosis in colorectal cancer beyond TNM
Authors: Neves Ana Lídia Ferreira , Barbosa Laura Elisabete Ribeiro , Teixeira João Paulo Meireles de Araújo
Published: September 2020

Introduction Colorectal cancer is one of the neoplasms with the greatest social impact. Given the great molecular heterogeneity and diversity of pathophysiological mechanisms, it is difficult to define prognostic factors that could guide therapy.

Objectives To identify the molecular prognostic factors that may be of interest in clinical practice and to synthesize the existing evidence.

Material and methods The search for the articles was carried out using the PubMed platform and the keywords “sporadic colorectal cancer and prognosis”, for articles published between 2014 and 2019. We selected all articles published on studies in humans and written in English or Portuguese. Of the 215 articles found, 35 articles were selected to perform this review.

Results Current evidence supports the use of four molecular markers in clinical practice − KRAS, NRAS and BRAF (EGFR signalling pathway) and the mismatch repair status.

Conclusion The use of molecular biomarkers in clinical practice to define prognosis is still little supported by the existent evidence. The studies are slightly contradictory, so new projects and international collaborations must be carried out in this area to obtain more robust evidence.
A Pragmatic Approach to the Perioperative Management of Parkinson’s Disease
Authors: Lenka Abhishek , Mittal Shivam Om , Lamotte Guillaume , Pagan Fernando Luis
Published: September 2020

Patients with Parkinson’s disease (PD) may undergo several elective and emergency surgeries. Motor fluctuations, the presence of a wide range of non-motor symptoms (NMS), and the use of several medications, often not limited to dopaminergic agents, make the perioperative management of PD challenging. However, the literature on perioperative management of PD is sparse. In this descriptive review article, we comprehensively discuss the issues in the pre-, intra-, and postoperative phases which may negatively affect the PD patients and discuss the approach to their prevention and management. The major preoperative challenges include accurate medication reconciliation and administration of the dopaminergic medications during thenil per os(NPO) state. While the former can be addressed with staff education and PD-specific admission protocols, knowledge of non-oral formulations of dopaminergic agents (apomorphine, inhalational levodopa, and rotigotine transdermal patch) is the key to the management of the Parkinsonian symptoms in NPO state. Deep brain stimulation (DBS) devices should be turned off to avert potential electromagnetic interference with surgical appliances. Choosing the appropriate anesthesia and avoiding and managing respiratory issues and dysautonomia are the major intraoperative challenges. Timely reinitiation of dopaminergic medications, adequate management of pain, nausea, and vomiting, and prevention of postoperative infections and delirium are the postoperative challenges. Overall, a multidisciplinary approach is pivotal to prevent and manage the perioperative complications in PD. Administration of anti-Parkinson medications during NPO state, prevention of anesthesia-related complications, and timely rehabilitation remain the key to healthy surgical outcomes.
Punishment and Retribution Within the Bail Process: An Analysis of the Public Confidence in the Administration of Justice Ground for Pre-Trial Detention
Authors: Manikis Marie , De Santi Jess
Published: September 2020

This paper argues that lower courts have used their discretionary powers provided within legislation and St-Cloud to infuse a predominantly retributive interpretation into the public confidence in the administration of justice ground of pre-trial detention. This is illustrated notably by their choice of and weight afforded to the various aggravating and mitigating factors, the circumstances that relate to the commission of the offence, as well as their analysis of the length of imprisonment. This transfer of sentencing rationales, and to a greater extent, retributivism, into the third ground of pre-trial detention is used, in part, to justify pre-trial detention and can partially explain the rates of pre-trial detention. Finally, the underlying sentencing logic within the bail process can be understood within a sociological perspective, which examines the wider social functions of institutions and suggests that the bail process is an extension of punishment that serves to reinstate social order and public confidence.
Atopidae (Trilobita) in the upper Marianian (Cambrian Series 2, Stage 4) of Iberia
Authors: Collantes Luis , Mayoral Eduardo , Liñán Eladio , Gozalo Rodolfo
Published: September 2020

New atopid trilobites are described from the early Cambrian Cumbres beds and Herrerías shale of northern Huelva Province (Andalusia, Spain) and are dated as middle–late Marianian (Cambrian Series 2, Stage 4). New specimens ofAtops calanusRichter and Richter, 1941 are described and the Laurentian speciesPseudatops reticulatus(Walcott, 1890b) is recognized for the first time in the Mediterranean subprovince. The associated trilobite assemblage studied herein suggests an age close to the base of Cambrian Stage 4.
Walk or Run to Quit: a 3-year evaluation of a physical activity-based smoking cessation intervention
Authors: Priebe Carly S. , Wunderlich Kelly , Atkinson John , Faulkner Guy
Published: September 2020

Introduction

Walk or Run to Quit was a national program targeting smoking cessation through group-based running clinics. Increasing physical activity may facilitate smoking cessation as well as lead to additional health benefits beyond cessation.

Aim

To evaluate the impact of Walk or Run to Quit over 3 years.

Methods

Adult male and female participants (N = 745) looking to quit smoking took part in 156 running-based cessation clinics in 79 locations across Canada. Using a pre-post design, participants completed questionnaires assessing physical activity, running frequency and smoking at the beginning and end of the 10-week program and at 6-months follow-up. Carbon monoxide testing pre- and post- provided an objective indicator of smoking status and coach logs assessed implementation.

Results

55.0% of program completers achieved 7-day point prevalence (intent-to-treat = 22.1%) and carbon monoxide significantly decreased from weeks 1 to 10 (P < 0.001). There was an increase in physical activity and running from baseline to end-of-program (P's<0.001). At 6-month follow-up, 28.9% of participants contacted self-reported prolonged 6-month abstinence (intent-to-treat = 11.4%) and 35.6% were still running regularly.

Conclusions

Although attrition was a concern, Walk or Run to Quit demonstrated potential as a scalable behaviour change intervention that targets both cessation and physical activity.
Fundraising for Stigmatized Groups: A Text Message Donation Experiment
Authors: LINOS KATERINA , JAKLI LAURA , CARLSON MELISSA
Published: September 2020

As government welfare programming contracts and NGOs increasingly assume core aid functions, they must address a long-standing challenge—that people in need often belong to stigmatized groups. To study other-regarding behavior, we fielded an experiment through a text-to-give campaign in Greece. Donations did not increase with an appeal to the in-group (Greek child) relative to a control (child), but they were halved with reference to a stigmatized out-group (Roma child). An appeal to fundamental rights, a common advocacy strategy, did not reduce the generosity gap. Donations to all groups were lower near Roma communities and declined disproportionately for the Roma appeal. Qualitative research in 12 communities complements our experiment. We conclude that NGO fundraising strategies that narrowly emphasize either in-groups or out-groups, or fundamental rights language, may not be as effective as broader appeals, and we discuss implications for public goods provision in an era of growing nationalism.
Magnetic resonance imaging in dogs with neuroangiostrongyliasis (rat lungworm disease)
Authors: Wun Matthew K. , Malik Richard , Yu Jane , Chow Kathleen E. , Lau Michelle , Podadera Juan M. , Webster Natalie , Lee Rogan , Šlapeta Jan , Davies Sarah
Published: September 2020

The magnetic resonance imaging (MRI) appearance of the brain and spinal cord in humans with neuroangiostrongyliasis (NA) due to Angiostrongylus cantonensis infection has been well reported. Equivalent studies in animals are lacking. This case series describes clinical and MRI findings in 11 dogs with presumptively or definitively diagnosed NA. MRI of the brain and/or spinal cord was performed using high-field (1.5 T) or low-field (0.25 T) scanners using various combinations of transverse, sagittal, dorsal and three-dimensional (3D) T1-weighted (T1W), transverse, sagittal and dorsal T2-weighted (T2W), T2W fluid-attenuated inversion recovery (FLAIR) and T2*-weighted (T2*W) gradient echo (GRE), dorsal T2W short tau inversion recovery (STIR) and post-gadolinium transverse, sagittal, dorsal and 3D T1W and transverse T2W FLAIR sequences. In 4/6 cases where the brain was imaged, changes consistent with diffuse meningoencephalitis were observed. Evidence of meningeal involvement was evident even when not clinically apparent. The spinal cord was imaged in 9 dogs, with evidence of meningitis and myelitis detected in regions consistent with the observed neuroanatomical localization. Pathognomonic changes of neural larva migrans, as described in some human patients with NA, were not detected. NA should be considered in the differential diagnosis of dogs with MRI evidence of focal or diffuse meningitis, myelitis and/or encephalitis, especially in areas where A. cantonensis is endemic. If not precluded by imaging findings suggestive of brain herniation, cerebrospinal fluid (CSF) collection for cytology, fluid analysis, real-time polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay (ELISA) testing should be considered mandatory in such cases after the MRI studies.
The incorporation of Traditional Ecological Knowledge in the Arctic Council: Lip service?
Authors: Sidorova Evgeniia (Jen)
Published: September 2020

The utilization of Traditional Ecological Knowledge (TEK) in wildlife management has been a prominent topic for several decades. Since its establishment, Arctic Council (AC) has emphasized the importance of TEK and its utilization in its work. Yet, the process of knowledge coproduction in the AC has never been assessed. To what extent has TEK been meaningfully incorporated into the AC? The research uses qualitative content analysis to analyze the AC working groups’ meeting minutes, reports, scientific reports and assessments as well as reports released by Permanent Participants in order to investigate how the TEK has been incorporated into the AC. The study investigates that the process of knowledge coproduction in the AC turned into lip service, and suggests the set of recommendations that could potentially guide the TEK projects in the process of knowledge co-production. These recommendations, including the use of participatory methodology, the use of Indigenous methods, a recognition that TEK is local, application to policy, and better cross-cultural communication, could result in the more meaningful integration of TEK into scientific projects as well as wildlife management policies.
Transdisciplinary science for improved conservation outcomes
Authors: Margules Chris , Boedhihartono Agni K , Langston James D , Riggs Rebecca A , Sari Dwi Amalia , Sarkar Sahotra , Sayer Jeffrey A , Supriatna Jatna , Winarni Nurul L
Published: September 2020

Major advances in biology and ecology have sharpened our understanding of what the goals of biodiversity conservation might be, but less progress has been made on how to achieve conservation in the complex, multi-sectoral world of human affairs. The failure to deliver conservation outcomes is especially severe in the rapidly changing landscapes of tropical low-income countries. We describe five techniques we have used to complement and strengthen long-term attempts to achieve conservation outcomes in the landscapes and seascapes of such regions; these are complex social-ecological systems shaped by interactions between biological, ecological and physical features mediated by the actions of people. Conservation outcomes occur as a result of human decisions and the governance arrangements that guide change. However, much conservation science in these countries is not rooted in a deep understanding of how these social-ecological systems work and what really determines the behaviour of the people whose decisions shape the future of landscapes. We describe five scientific practices that we have found to be effective in building relationships with actors in landscapes and influencing their behaviour in ways that reconcile conservation and development. We have used open-ended inductive enquiry, theories of change, simulation models, network analysis and multi-criteria analysis. These techniques are all widely known and well tested, but seldom figure in externally funded conservation projects. We have used these techniques to complement and strengthen existing interventions of international conservation agencies. These five techniques have proven effective in achieving deeper understanding of context, engagement with all stakeholders, negotiation of shared goals and continuous learning and adaptation.
Effects of mobile-supported task-based language teaching on EFL students’ linguistic achievement and conversational interaction
Authors: Fang Wei-Chieh , Yeh Hui-Chin , Luo Bo-Ru , Chen Nian-Shing
Published: September 2020

To address the challenges of limited language proficiency and provide necessary feedback in the implementation of task-based language teaching (TBLT), a mobile-supported TBLT application was developed to provide linguistic and task scaffolding. Sixty-six English as a foreign language (EFL) university learners participated in a three-week experiment as part of a general English course. They were assigned to either an experimental group (mobile-supported TBLT), which received TBLT with scaffolds built into the application, or a control group (traditional TBLT), which received traditional paper-based TBLT without the scaffolds. At the end of the experiment, an English achievement test of vocabulary, grammar, and conversation comprehension was administered to determine if the technological scaffolds enhanced the learning outcomes for the course. Students’ self-perceived use of oral communication strategies was also measured to explore how these scaffolds affected the conversational interaction essential for task performance. Results showed that the mobile-supported TBLT group outperformed the traditional TBLT group on the vocabulary and conversation comprehension tests but not so much on the grammar test. Also, the mobile-supported TBLT group reported greater awareness of fluency- and accuracy-oriented strategies for speaking than the traditional TBLT group. Implications for designing mobile learning to enhance TBLT in an EFL setting are drawn.
WHAT’S GOING ON?
Authors: Stephens Pamela , Pastor Manuel
Published: September 2020

Once nearly eighty percent Black, South LA is now two-thirds Latino. The demographic change was due to many factors, including a Black exodus driven by economic precarity, fear of crime, and experiences of over-policing and a Latino influx initially spurred by an immigration surge that could not be accommodated in traditional entry neighborhoods. While earlier research often focused on the conflicts between groups, time has passed and our new work points to contemporary quotidian accommodations between residents. We also document an emerging style of Black-Brown community organizing that seeks to both acknowledge the nuance of differenceandcreate a shared sense of place identity. This article lifts up the Black experience in that transition of space and politics and notes how a sense of loss can result from such a dramatic change in a place that was once an iconic and literal home for much of Black Los Angeles. We suggest that that sense of loss is exacerbated by a legacy of racist asset-stripping and a deep worry about Black erasure due to current displacement pressures from gentrification. We close by discussing how organizers and political leaders need to take these dynamics into account when both building coalitions and ensuring Black futures in what is now a Black-Brown political and social space.
Uncertainties in Drought From Index and Data Selection
Authors: Hoffmann David , Gallant Ailie J. E. , Arblaster Julie M.
Published: September 2020

This study compares various drought indices, the Palmer Drought Severity Index (PDSI), the Standardized Precipitation Evapotranspiration Index (SPEI), and the Standardized Precipitation Index (SPI), and the uncertainties in each to the input data from which they are derived. The abilities of the PDSI, SPEI, and SPI to capture drought periods are assessed through a comparison with soil moisture estimates from two generations of the Global Land Data Assimilation System (GLDAS). This comparison shows that the skill with which a drought index represents variations in soil moisture does not necessarily improve when evapotranspiration is included (i.e., PDSI/SPEI rather than SPI), though this depends on location and the time scale of the drought. The differences in the abilities of the drought indices to represent soil moisture are also compared to the magnitude of the uncertainty in each index arising from the choice of input data. In many cases, the uncertainties in the variations of the PDSI, SPEI, and SPI to the choice of input data are larger in magnitude than the differences between the indices themselves, particularly when considering the dry tails of the distribution. The results show that no one drought index outperforms the others during drought conditions.
Lightning Interferometry Uncertainty, Beam Steering Interferometry, and Evidence of Lightning Being Ignited by a Cosmic Ray Shower
Authors: Shao Xuan‐Min , Ho Cheng , Bowers Gregory , Blaine William , Dingus Brenda
Published: September 2020

We present an uncertainty analysis on correlation‐based time delay estimate, the basis for broadband lightning interferometry. A normal interferometry would yield much higher uncertainties than the theoretically predicted lower bound due to finite correlation window lengths. However, if the signals are aligned in time, the uncertainties approach the lower bound and can be used to indicate the interferometric uncertainties. Based on this, we introduce a beam steering interferometry technique. It first estimates a direction centroid for the lightning sources with a normal interferometry and computes the time delays among the signals. It then shifts the raw data with the time delays to align the signals roughly in time and reprocess the aligned signals. It finally pushes the reprocessed results to their correct positions, based on the time delays estimated in the first step. We apply this technique on a fast positive breakdown (FPB) process that started a normal intracloud lightning. The FPB process is shown to have a much more complex structure and development than a normal interferometry would provide. More importantly, from both interferometric and polarization analyses, the FPB appears to be ignited by a cosmic ray shower (CRS). We estimate the radio frequency strength and frequency content related to a presumed CRS in a thunderstorm electric field and find that they are in agreement with the observations. We examine the electric field effect of the CRS front and find that it could raise the field above the threshold for positive breakdown and is capable of igniting the FPB (and the lightning).
The Impact of a Six‐Year Climate Anomaly on the “Spanish Flu” Pandemic and WWI
Authors: More Alexander F. , Loveluck Christopher P. , Clifford Heather , Handley Michael J. , Korotkikh Elena V. , Kurbatov Andrei V. , McCormick Michael , Mayewski Paul A.
Published: September 2020

The H1N1 “Spanish influenza” pandemic of 1918–1919 caused the highest known number of deaths recorded for a single pandemic in human history. Several theories have been offered to explain the virulence and spread of the disease, but the environmental context remains underexamined. In this study, we present a new environmental record from a European, Alpine ice core, showing a significant climate anomaly that affected the continent from 1914 to 1919. Incessant torrential rain and declining temperatures increased casualties in the battlefields of World War I (WWI), setting the stage for the spread of the pandemic at the end of the conflict. Multiple independent records of temperature, precipitation, and mortality corroborate these findings.
Changes in Crater Geometry Revealed by Inversion of Harmonic Infrasound Observations: 24 December 2018 Eruption of Mount Etna, Italy
Authors: Watson Leighton M. , Johnson Jeffrey B. , Sciotto Mariangela , Cannata Andrea
Published: September 2020

In December 2018, Mount Etna (Italy) experienced a period of increased eruptive activity that culminated in a fissure eruption on the southeast flank. After the onset of the flank eruption, the peak frequency of the summit infrasound signals decreased while resonance increased. We invert infrasound observations for crater geometry and show that crater depth and radius increased during the eruption, which suggests that the flank eruption drained magma from the summit and that eruptive activity led to erosion of the crater wall. By inverting the entire infrasound amplitude spectra rather than just the peak frequency, we are able to place additional constraints on the crater geometry and invert for, rather than assume, the crater shape. This work illustrates how harmonic infrasound observations can be used to obtain high‐temporal‐resolution information about crater geometry and can place constraints on complex processes occurring in the inaccessible crater region during eruptive activity.
Evolution of Aerosol Under Moist and Fog Conditions in a Rural Forest Environment: Insights From High‐Resolution Aerosol Mass Spectrometry
Authors: Zhang Jie , Lance Sara , Marto Joseph , Sun Yele , Ninneman Matthew , Crandall Brian A. , Wang Junfeng , Zhang Qi , Schwab James J.
Published: September 2020

The effect of foggy/moist conditions on the characteristics of secondary organic aerosol (SOA) was studied. Analysis of the high‐resolution time‐of‐flight aerosol mass spectrometer measurements identified two fresh biogenic SOA factors (BSOA: BSOA‐1 and BSOA‐2), hypothesized to be formed through the nighttime reaction of biogenic volatile organic compounds with nitrate radical. During foggy periods, the more oxidized oxygenated OA (MO‐OOA) was scavenged most efficiently (86% removal), followed by the less oxidized OOA (LO‐OOA) (55%), SO4 (53%), and BSOA (25%). Aerosol mass increased during fog events, and the post‐fog aerosol mass was higher (11%) than during the prefog period, with a reduction for MO‐OOA and an enhancement for LO‐OOA and BSOA. The high positive correlation observed between aerosol liquid water (ALW) and BSOA suggests the importance of aqueous‐phase processing on the BSOA formation, and an increase in log10(ALW) of 1 corresponded to an average increase of about 0.9 μg m−3 in BSOA.
Thermocline Warming Induced Extreme Indian Ocean Dipole in 2019
Authors: Du Yan , Zhang Yuhong , Zhang Lian‐Yi , Tozuka Tomoki , Ng Benjamin , Cai Wenju
Published: September 2020

The 2019 positive Indian Ocean Dipole (IOD) was the strongest event since the 1960s which developed independently without coinciding El Niño. The dynamics is not fully understood. Here we show that in March–May, westward propagating oceanic Rossby waves, a remnant consequence of the weak 2018 Pacific warm condition, led to anomalous sea surface temperature warming in the southwest tropical Indian Ocean (TIO), inducing deep convection and anomalous easterly winds along the equator, which triggered the initial cooling in the east. In June–August, the easterly wind anomalies continued to evolve through ocean‐atmosphere coupling involving Bjerknes feedback and equatorial nonlinear ocean advection, until its maturity in September–November. This study clarifies the contribution of oceanic Rossby waves in the south TIO in different dynamic settings and reveals a new triggering mechanism for extreme IOD events that will help to understand IOD diversity.
Influence of Fluid‐Assisted Healing on Fault Permeability Structure
Authors: Yehya Alissar , Rice James R.
Published: September 2020

Microcracks in fault damage zones can heal under thermally controlled processes. If a flow communication exists between a fluid source and the fault damage zone, warm fluids can migrate into it, change its thermal conditions, and assist healing. The crack life span depends on the local temperature and is, thus, modified by the infiltration of warm fluids. The features of the initial fault architecture govern how the fluids will propagate within the fault damage zones. This affects the rate of healing and the rate of permeability reduction. The region infiltrated by fluids will then show a significant decrease in its permeability, as seen in many field examples like the Alpine Fault. Conventionally, the damage zones immediately near the fault core have a high permeability that decays as we go further away. However, the region adjacent to the fault core, in the Alpine Fault, New Zealand, has the lowest permeability in the current interseismic period. As shown by our simulations, this can be due to healing and sealing, favored by the localized high geothermal gradients (confirmed by the drilling data) and the upward fluid migration through the fault relay structure, which accelerated mass diffusion and minerals precipitation.
Residual Sediment Transport in Tidally Energetic Estuarine Channels With Lateral Bathymetric Variation
Authors: Zhou Jian , Stacey Mark T.
Published: September 2020

The residual sediment transport in tidally energetic estuarine channels is investigated by means of idealized cross‐sectional modeling. The lateral bathymetric variation follows a Gaussian profile, assuming longitudinal uniformity. The total along‐channel residual sediment flux is decomposed into contributions from an advective flux and a tidal pumping flux. Two important mechanisms are found to modify the tidal covariance between sediment concentration and current velocity, thereby contributing to the tidal pumping of sediment. First, longitudinal and lateral straining of salinity leads to tidal asymmetries in stratification and thus sediment resuspension. Second, lateral circulations directly redistribute suspended sediments within the cross section, which are then differentially transported by the along‐channel tidal currents. A general relationship between the phasing of the lateral circulations and the resulting lateral‐advection‐driven tidal pumping is proposed. Reduced‐physics experiments with lateral sediment advection turned off provide the first evidence that lateral‐advection‐driven tidal pumping plays a leading role in sediment transport for tidally energetic estuaries with nonnegligible lateral depth gradients. Additionally, a temporal decomposition breaks down the cross‐sectionally averaged tidal pumping flux into individual contributions from different tidal phases (early tide, peak tide, and late tide), providing a new perspective on tidal asymmetry in sediment resuspension and settling. The direction and strength of tidal pumping (both stratification‐driven and lateral‐advection‐driven) are shown to depend on lateral bathymetry, sediment grain size, and longitudinal buoyancy gradient forcing.
Intracrater Sediment Trapping and Transport in Arabia Terra, Mars
Authors: Dorn Taylor , Day Mackenzie
Published: September 2020

Craters are the most prevalent basins and potential depocenters of sediment on Mars. Within these craters and extending from them, terminal dune fields and wind streaks are abundant, indicating active sediment transport and providing a way to study how wind and sediment interact with crater topography. Here we explore the role of craters as both sources and sinks in the modern Martian sedimentary cycle. Our results show that craters with low albedo wind streaks (indicative of sediment transport out of a crater and downwind dust removal) have lower crater wall slopes (9.4° ± 5.5°) compared to craters without wind streaks (17° ± 5.8°). We interpret that crater wall slopes play a dominant role in whether sediment is transported out of a crater basin and infer, from measurements of craters on Mars, that a crater transitions from being a net sediment sink to a net sediment source when crater wall slopes decrease to ~15°. This threshold value is consistent with limits of bedform climb observed on Earth and elsewhere on Mars.
Where Have All the Nutrients Gone? Long‐Term Decoupling of Inputs and Outputs in the Willamette River Watershed, Oregon, United States
Authors: Metson Genevieve S. , Lin Jiajia , Harrison John A. , Compton Jana E.
Published: September 2020

Better documentation and understanding of long‐term temporal dynamics of nitrogen (N) and phosphorus (P) in watersheds is necessary to support effective water quality management, in part because studies have identified time lags between terrestrial nutrient balances and water quality. We present annual time series data from 1969 to 2012 for terrestrial N and P sources and monthly data from 1972 to 2013 for river N and P for the Willamette River Basin, Oregon, United States. Inputs to the watershed increased by factors of 3 for N and 1.2 for P. Synthetic fertilizer inputs increased in total and relative importance over time, while sewage inputs decreased. For N, increased fertilizer application was not matched by a proportionate increase in crop harvest; N use efficiency decreased from 69% to 38%. P use efficiency increased from 52% to 67%. As nutrient inputs to terrestrial systems increased, river concentrations and loads of total N, total P, and dissolved inorganic P decreased, and annual nutrient loads were strongly related to discharge. The N:P ratio of both sewage and fertilizer doubled over time but there was no similar trend in riverine export; river N:P concentrations declined dramatically during storms. River nutrient export over time was related to hydrology and waste discharge, with relatively little influence of watershed balances, suggesting that accumulation within soils or groundwater over time is mediating watershed export. Simply managing yearly nutrient balances is unlikely to improve water quality; rather, many factors must be considered, including soil and groundwater storage capacity, and gaseous loss pathways.
Stormflows Drive Stream Carbon Concentration, Speciation, and Dissolved Organic Matter Composition in Coastal Temperate Rainforest Watersheds
Authors: Fellman Jason B. , Hood Eran , Behnke Megan I. , Welker Jeffrey M. , Spencer Robert G. M.
Published: September 2020

Stream water carbon concentrations can be highly dynamic on the time scales of both individual storm events and seasonal hydroclimatic shifts. We collected stream water daily over a 6‐day storm from three headwater subcatchments of varying landcover (poor fen, forested wetland, and upland forest) and the catchment outlet to evaluate how precipitation events impact the concentration and speciation of carbon (organic vs. inorganic) as well as the composition of dissolved organic matter (DOM) exported laterally from coastal temperate rainforest catchments. Dissolved and particulate organic carbon concentrations increased during the storm at all sites, while dissolved inorganic carbon concentrations were diluted during peak flows. These results highlight the importance of quantifying all forms of lateral carbon export when evaluating the role of storms in catchment‐scale carbon cycling. Isotopic hydrograph separation using stream water δ18O showed that percent new water was significantly related to carbon concentration and form providing a clear link between stream water sources (i.e., recent event water) and soil carbon source areas that become connected to surface water during storms. Furthermore, ultrahigh‐resolution mass spectrometry showed that stream water DOM exported from the upland forest contained the greatest molecular diversity of the three landscape types and had the largest changes in composition over the storm suggesting that the wetland‐dominated subcatchments were less compositionally diverse with regard to soil DOM pools active during the storm. Overall, this study provides insight into hydro‐biogeochemical drivers that control lateral carbon export from forested catchments in a region where an increasing fraction of precipitation is falling as rain.
Standards of care in mesothelioma treatment
Authors: Harden Susan V. , Darlison Liz , Beckett Paul , Bibby Anna C.
Published: September 2020

The UK has the highest incidence of mesothelioma in the world, but services vary across the country partly due to uneven geographical distribution of cases. The Mesothelioma UK-funded national organisational audit has highlighted challenges in accessing diagnostic procedures such as thoracoscopy, as well as identifying examples of best practice, including access to clinical trials and specialist therapeutic procedures. To ensure equitable and optimal patient care, cancer alliances should have established referral pathways to specialist multidisciplinary team (MDT) services for discussion of all mesothelioma patients.
India’s potential for integrating solar and on- and offshore wind power into its energy system
Authors: Lu Tianguang , Sherman Peter , Chen Xinyu , Chen Shi , Lu Xi , McElroy Michael
Published: September 2020

This paper considers options for a future Indian power economy in which renewables, wind and solar, could meet 80% of anticipated 2040 power demand supplanting the country’s current reliance on coal. Using a cost optimization model, here we show that renewables could provide a source of power cheaper or at least competitive with what could be supplied using fossil-based alternatives. The ancillary advantage would be a significant reduction in India’s future power sector related emissions of CO2. Using a model in which prices for wind turbines and solar PV systems are assumed to continue their current decreasing trend, we conclude that an investment in renewables at a level consistent with meeting 80% of projected 2040 power demand could result in a reduction of 85% in emissions of CO2 relative to what might be expected if the power sector were to continue its current coal dominated trajectory.
Oxygen vacancy-driven orbital multichannel Kondo effect in Dirac nodal line metals IrO2 and RuO2
Authors: Yeh Sheng-Shiuan , Su Ta-Kang , Lien An-Shao , Zamani Farzaneh , Kroha Johann , Liao Chao-Ching , Kirchner Stefan , Lin Juhn-Jong
Published: September 2020

Strong electron correlations have long been recognized as driving the emergence of novel phases of matter. A well recognized example is high-temperature superconductivity which cannot be understood in terms of the standard weak-coupling theory. The exotic properties that accompany the formation of the two-channel Kondo (2CK) effect, including the emergence of an unconventional metallic state in the low-energy limit, also originate from strong electron interactions. Despite its paradigmatic role for the formation of non-standard metal behavior, the stringent conditions required for its emergence have made the observation of the nonmagnetic, orbital 2CK effect in real quantum materials difficult, if not impossible. We report the observation of orbital one- and two-channel Kondo physics in the symmetry-enforced Dirac nodal line (DNL) metals IrO2 and RuO2 nanowires and show that the symmetries that enforce the existence of DNLs also promote the formation of nonmagnetic Kondo correlations. Rutile oxide nanostructures thus form a versatile quantum matter platform to engineer and explore intrinsic, interacting topological states of matter.
Regulation of cellular sterol homeostasis by the oxygen responsive noncoding RNA lincNORS
Authors: Wu Xue , Niculite Cristina M. , Preda Mihai Bogdan , Rossi Annalisa , Tebaldi Toma , Butoi Elena , White Mattie K. , Tudoran Oana M. , Petrusca Daniela N. , Jannasch Amber S. , Bone William P. , Zong Xingyue , Fang Fang , Burlacu Alexandrina , Paulsen Michelle T. , Hancock Brad A. , Sandusky George E. , Mitra Sumegha , Fishel Melissa L. , Buechlein Aaron , Ivan Cristina , Oikonomopoulos Spyros , Gorospe Myriam , Mosley Amber , Radovich Milan , Davé Utpal P. , Ragoussis Jiannis , Nephew Kenneth P. , Mari Bernard , McIntyre Alan , Konig Heiko , Ljungman Mats , Cousminer Diana L. , Macchi Paolo , Ivan Mircea
Published: September 2020

We hereby provide the initial portrait of lincNORS, a spliced lincRNA generated by the MIR193BHG locus, entirely distinct from the previously described miR-193b-365a tandem. While inducible by low O2 in a variety of cells and associated with hypoxia in vivo, our studies show that lincNORS is subject to multiple regulatory inputs, including estrogen signals. Biochemically, this lincRNA fine-tunes cellular sterol/steroid biosynthesis by repressing the expression of multiple pathway components. Mechanistically, the function of lincNORS requires the presence of RALY, an RNA-binding protein recently found to be implicated in cholesterol homeostasis. We also noticed the proximity between this locus and naturally occurring genetic variations highly significant for sterol/steroid-related phenotypes, in particular the age of sexual maturation. An integrative analysis of these variants provided a more formal link between these phenotypes and lincNORS, further strengthening the case for its biological relevance.
Rational programming of history-dependent logic in cellular populations
Authors: Zúñiga Ana , Guiziou Sarah , Mayonove Pauline , Meriem Zachary Ben , Camacho Miguel , Moreau Violaine , Ciandrini Luca , Hersen Pascal , Bonnet Jerome
Published: September 2020

Genetic programs operating in a history-dependent fashion are ubiquitous in nature and govern sophisticated processes such as development and differentiation. The ability to systematically and predictably encode such programs would advance the engineering of synthetic organisms and ecosystems with rich signal processing abilities. Here we implement robust, scalable history-dependent programs by distributing the computational labor across a cellular population. Our design is based on standardized recombinase-driven DNA scaffolds expressing different genes according to the order of occurrence of inputs. These multicellular computing systems are highly modular, do not require cell-cell communication channels, and any program can be built by differential composition of strains containing well-characterized logic scaffolds. We developed automated workflows that researchers can use to streamline program design and optimization. We anticipate that the history-dependent programs presented here will support many applications using cellular populations for material engineering, biomanufacturing and healthcare.
GPR101 drives growth hormone hypersecretion and gigantism in mice via constitutive activation of Gs and Gq/11
Authors: Abboud Dayana , Daly Adrian F. , Dupuis Nadine , Bahri Mohamed Ali , Inoue Asuka , Chevigné Andy , Ectors Fabien , Plenevaux Alain , Pirotte Bernard , Beckers Albert , Hanson Julien
Published: September 2020

Growth hormone (GH) is a key modulator of growth and GH over-secretion can lead to gigantism. One form is X-linked acrogigantism (X-LAG), in which infants develop GH-secreting pituitary tumors over-expressing the orphan G-protein coupled receptor, GPR101. The role of GPR101 in GH secretion remains obscure. We studied GPR101 signaling pathways and their effects in HEK293 and rat pituitary GH3 cell lines, human tumors and in transgenic mice with elevated somatotrope Gpr101 expression driven by the rat Ghrhr promoter (GhrhrGpr101). Here, we report that Gpr101 causes elevated GH/prolactin secretion in transgenic GhrhrGpr101 mice but without hyperplasia/tumorigenesis. We show that GPR101 constitutively activates not only Gs, but also Gq/11 and G12/13, which leads to GH secretion but not proliferation. These signatures of GPR101 signaling, notably PKC activation, are also present in human pituitary tumors with high GPR101 expression. These results underline a role for GPR101 in the regulation of somatotrope axis function.