bluuebunny/crossref_metadata_2025 huggingface dataset:
Symbolic dynamics for one dimensional maps with nonuniform expansion
Authors: Lima Yuri
Published: November 2019

Given a piecewise

C^{1 + \beta }

map of the interval, possibly with critical points and discontinuities, we construct a symbolic model for invariant probability measures with nonuniform expansion that do not approach the critical points and discontinuities exponentially fast almost surely. More specifically, for each

\chi > 0

we construct a finite-to-one Hölder continuous map from a countable topological Markov shift to the natural extension of the interval map, that codes the lifts of all invariant probability measures as above with Lyapunov exponent greater than
χ
almost everywhere.
Aggregation-diffusion to constrained interaction: Minimizers & gradient flows in the slow diffusion limit
Authors: Craig Katy , Topaloglu Ihsan
Published: November 2019

Inspired by recent work on minimizers and gradient flows of constrained interaction energies, we prove that these energies arise as the slow diffusion limit of well-known aggregation-diffusion energies. We show that minimizers of aggregation-diffusion energies converge to a minimizer of the constrained interaction energy and gradient flows converge to a gradient flow. Our results apply to a range of interaction potentials, including singular attractive and repulsive-attractive power-law potentials. In the process of obtaining the slow diffusion limit, we also extend the well-posedness theory for aggregation-diffusion equations and Wasserstein gradient flows to admit a wide range of nonconvex interaction potentials. We conclude by applying our results to develop a numerical method for constrained interaction energies, which we use to investigate open questions on set valued minimizers.
The Role of Inflammation after Surgery for Elders (RISE) study: Study design, procedures, and cohort profile
Authors: Hshieh Tammy T. , Vasunilashorn Sarinnapha M. , D'Aquila Madeline L. , Arnold Steven E. , Dickerson Bradford C. , Fong Tamara G. , Jones Richard N. , Marcantonio Edward R. , Schmitt Eva M. , Xu Guoquan , Gou Yun , Chen Fan , Kunze Lisa J. , Vlassakov Kamen V. , Abdeen Ayesha R. , Lange Jeffrey K. , Earp Brandon E. , Touroutoglou Alexandra , Carlyle Becky C. , Kivisakk‐Webb Pia , Travison Thomas G. , Dillon Simon T. , Libermann Towia A. , Inouye Sharon K. ,   RISE Study Group, Inouye Sharon K. , Arnold Steven , Dickerson Bradford , Fong Tamara , Jones Richard , Libermann Towia A. , Marcantonio Edward R. , Travison Thomas , Carlyle Becky C. , Cavallari Michele , Dillon Simon T. , Hooker Jacob , Hshieh Tammy , Kandigian Savannah , Kivisakk‐Webb Pia , Ngo Long , Otu Hasan , Schmitt Eva M. , Touroutoglou Alexandra , Trombetta Bianca , Vasunilashorn Sarinnapha , Abdeen Ayesha , Ayres Douglas , Earp Brandon , Lange Jeffrey , Brick Gregory , Chen Antonia , Davis Robert , Drew Jacob , Iorio Richard , Kornack Fulton , Weaver Michael , Webber Anthony , Wilk Richard , Kunze Lisa , Shaff David , Vlassakov Kamen , Armstrong Brett , Banda Angelee , Bertrand Sylvie , D'Aquila Madeline , Gallagher Jacqueline , Hightower Baileigh , Malloy Shannon , Nee Jacqueline , Nobuhara Chloe , Overstreet Abigail , Racine Annie , Urick David , Xu Guoquan , Arabasz Grae , Brickhouse Michael , Butterfield Regan , Hsu Shirley , Makaretz Sara , Sore Judit , Chen Fan , Gou Yun , Tommet Douglas , Carretie Sabrina , Gruen Ted , Tasker Katherine
Published: November 2019

Introduction

The Role of Inflammation after Surgery for Elders study correlates novel inflammatory markers measured in blood, cerebrospinal fluid (CSF) assays, and [11C]‐PBR28 positron‐emission tomography imaging.

Methods

This study involved a prospective cohort design with patients who underwent elective hip and knee arthroplasty under spinal anesthesia. Sixty‐five adults participated with their family members. Inflammatory biomarker assays were measured preoperatively on day 1 and postoperatively at one month.

Results

On average, participants were 75 years old, and 72% were female. 54% underwent total knee arthroplasty, and 46% underwent total hip arthroplasty. The mean Modified Mini‐Mental State (3MS) Examination score was 89.3; four patients (6%) scored ≤77 points. Plasma assays were completed in 63 (97%) participants, cerebrospinal fluid assays in 61 (94%), and PET imaging in 44 (68%).

Discussion

This complex study presents an innovative effort to correlate peripheral and central inflammatory biomarkers before and after major surgery in older adults. Strengths include collecting concurrent blood, cerebrospinal fluid, and positron‐emission tomography with detailed clinical characterization of delirium, cognition, and functional status.
Episodic Prenatal Exposure To Ethanol Affects Postnatal Neurogenesis In The Macaque Dentate Gyrus And Visual Recognition Memory
Authors: Fedorchak Alexis V. , Miller Michael W.
Published: November 2019

Fetal alcohol syndrome (FAS) is a prime cause of cognitive dysfunction. The present study tested the hypotheses (a) that gestational ethanol exposure results in deficits in hippocampal‐related behaviors and associated neurogenesis and (b) that the period of gastrulation is a time of vulnerability. Pregnant macaques were intubated with ethanol or saline once per week for 3, 6, or 24 weeks. Exposures included or omitted the period of gastrulation. Offspring were given behavioral tests including a Visual‐Paired Comparison (VPC), a hippocampal‐associated memory task, and euthanized as adolescents. Their dentate gyri were processed for immunohistochemical identification of cells passing through the cell cycle (Ki‐67 and proliferating cell nuclear antigen), exiting the cell cycle (p21), or passing through early stages of neuronal morphogenesis (Tuj1). Performance in neurobehavioral tasks was unaffected by ethanol exposure, the notable exception being performance in the VPC that was poorer for macaques exposed to ethanol including gastrulation. Anatomical studies show that the expression of Ki‐67 was greater and ratio of p21‐positive cells to the ratio of Ki‐67‐expressing cells was lower in animals in which the ethanol exposure included gastrulation. On the other hand, no ethanol‐induced differences in TuJ1 expression were detected. Thus, the dentate gyrus is a bellwether of long‐term consequences of gestational ethanol exposure. Targeted effects of ethanol on early neural generation (cell cycle and cycle exit) correlate with the timing‐dependent degradation in VPC performance and exposure during gastrulation results in notable deficits. These changes evidence a pattern of fetal programming underlying FAS.
Making steel powders for PM and AM
Authors: Capus Joseph
Published: November 2019

The production and properties of steel powders for PM, MIM, and AM were discussed by leading producers in a Special Interest Program of oral presentations at the POWDERMET2019 and AMPM conferences in Phoenix.
Linking the low‐density lipoprotein receptor‐binding segment enables the therapeutic 5‐YHEDA peptide to cross the blood‐brain barrier and scavenge excess iron and radicals in the brain of senescent mice
Authors: Zou Zhenyou , Shao Shengxi , Zou Ruyi , Qi Jini , Chen Liguan , Zhang Hui , Shen Qiqiong , Yang Yue , Ma Liman , Guo Ruzeng , Li Hongwen , Tian Haibo , Li Pengxin , Yu Mingfang , Wang Lu , Kong Wenjuan , Li Caiyu , Yu Zhenhai , Huang Yuping , Chen Li , Shao Qi , Gao Xinyan , Chen Xiaolin , Zhang Zhengbo , Yan Jianguo , Shao Xiaoyun , Pan Ru , Xu Lu , Fang Jing , Zhao Lei , Huang Yaohui , Li Anqi , Zhang Yuchong , Huang Wenkao , Tian Kechun , Hu Minxin , Xie Linchao , Wu Lingbin , Wu Yu , Luo Zhen , Xiao Wenxin , Ma Shanshan , Wang Jianan , Huang Kaixin , He Siyuan , Yang Fan , Zhou Shuni , Jia Mo , Zhang Hui , Lu Hongsheng , Wang Xinjuan , Tan Jie
Published: November 2019

Introduction

Iron accumulates in the brain during aging, which catalyzes radical formation, causing neuronal impairment, and is thus considered a pathogenic factor in Alzheimer's disease (AD). To scavenge excess iron‐catalyzed radicals and thereby protect the brain and decrease the incidence of AD, we synthesized a soluble pro‐iron 5‐YHEDA peptide. However, the blood‐brain barrier (BBB) blocks large drug molecules from entering the brain and thus strongly reduces their therapeutic effects. However, alternative receptor‐ or transporter‐mediated approaches are possible.

Methods

A low‐density lipoprotein receptor (LDLR)‐binding segment of Apolipoprotein B‐100 was linked to the 5‐YHEDA peptide (bs‐5‐YHEDA) and intracardially injected into senescent (SN) mice that displayed symptoms of cognitive impairment similar to those of people with AD.

Results

We successfully delivered 5‐YHEDA across the BBB into the brains of the SN mice via vascular epithelium LDLR‐mediated endocytosis. The data showed that excess brain iron and radical‐induced neuronal necrosis were reduced after the bs‐5‐YHEDA treatment, together with cognitive amelioration in the SN mouse, and that the senescence‐associated ferritin and transferrin increase, anemia and inflammation reversed without kidney or liver injury.

Discussion

bs‐5‐YHEDA may be a mild and safe iron remover that can cross the BBB and enter the brain to relieve excessive iron‐ and radical‐induced cognitive disorders.
Family Medicine Patient and Physician Attitudes Toward Climate Change and Health in Wisconsin
Authors: Boland Taylor M. , Temte Jonathan L.
Published: November 2019

Introduction

Climate change is an increasingly relevant public health issue attracting increasing amounts of attention. Despite family medicine being at the front line for public health, no recent studies have assessed the opinions of physicians and patients regarding climate change and health in the family medicine setting.

Methods

Surveys were distributed to adult patients in the waiting rooms of 4 University of Wisconsin Department of Family Medicine and Community Health clinics. Four hundred three patient surveys were collected, for an 86% response rate. An online survey was distributed to all University of Wisconsin Department of Family Medicine and Community Health physicians. Fifty-eight surveys were collected for a 32% response rate.

Results

Forty-four percent of patients believe climate change is currently affecting their community’s health. Patients have high trust in their physician regarding environmental issues (median=4 out of 5), and 6% of patients ranked their physician as a top source of information on this topic. Sixty-four percent of physicians believe climate change is affecting their patients’ health, and 17% are comfortable counseling patients about climate change and health. Although 71% of physicians believe climate change is relevant to primary care, 31% believe that physicians should have an active role in discussing climate change with patients.

Conclusions

Patients and physicians are concerned about climate change and its health implications. Patient data reveals that physicians are highly trusted but underutilized sources. However, physicians are unsure of their role in addressing this topic. Thus, a large opportunity exists for family physicians to educate patients on the emerging issue of climate change and health.
Effect of microramps on flare-induced shock – boundary-layer interaction
Authors: Nilavarasan T. , Joshi G. N. , Misra A.
Published: November 2019

The ability of microramps to control shock - boundary layer interaction at the vicinity of an axisymmetric compression corner was investigated computationally in a Mach 4 flow. A cylinder/flare model with a flare angle of 25° was chosen for this study. Height (h) of the microramp device was 22% of the undisturbed boundary layer thickness (δ) obtained at the compression corner location. A single array of these microramps with an inter-device spacing of 7.5h was placed at three different streamwise locations viz. 5δ, 10δ and 15δ (22.7h, 45.41h and 68.12h in terms of the device height) upstream of the corner and the variations in the flowfield characteristics were observed. These devices modified the separation bubble structure noticeably by producing alternate upwash and downwash regions in the boundary layer. Variations in the separation bubble’s length and height were observed along the spanwise (circumferential) direction due to these devices.
Do demographic changes affect house prices?
Authors: Gevorgyan Kristine
Published: November 2019

The paper tests the idea that major demographic shifts can affect housing prices. We first build an overlapping generation model and analytically solve for the equilibrium price of the asset. The model predicts that economies with a higher fraction of old people in the overall population have lower house prices. We empirically test this hypothesis using data on house prices and demographic variables from the Organization for Economic Co-operation and Development (OECD). We find that if population growth increases by one percentage point, house price growth increases by 1.4 percentage points.
Using fMRI to deepen our understanding of design fixation
Authors: Fu Katherine K. , Sylcott Brian , Das Kaustav
Published: November 2019

Design fixation refers to blind adherence to a set of ideas, which can limit the output of conceptual design. Engineering designers tend to fixate on features of pre-existing solutions and consequently generate designs with similar features. The objective of this study is to leverage functional magnetic resonance imaging (fMRI) to study the brain activity of engineering designers during conceptual design in order to understand whether/where design fixation can be detected in a person’s brain when solving design problems. Design solutions indicated that fixation effects were detectable at a statistically significant level. fMRI results show increased activation in areas associated with visuospatial processing when comparing ideation activities using an Example solution to No Example solution. Activation was found in the right inferior temporal gyrus, left middle occipital gyrus, and right superior parietal lobule regions. The left lingual and superior frontal gyri were found to be less active in the example condition; these gyri are close in proximity to the prefrontal cortex, associated with creative output. The spatial patterns of activation provide evidence that a shift in mental resources can occur when a designer becomes fixated. For designers, the timing of ideation relative to the timing of benchmarking existing solutions should be considered.
Teaching Citizenship: Race and the Behavioral Effects of American Civic Education
Authors: Nelsen Matthew D.
Published: November 2019

Political scientists have identified how resources, attitudes, and mobilization impact political participation across racial groups. However, the role of civic education has largely been overlooked in shaping these trends. I develop a theory that suggests exposure to civics curricula yields heterogeneous effects on the political participation of youth across racial groups. I test my hypotheses with data from the Black Youth Project's 2005 Youth Culture Survey, supplemented by two original data collections from 2017–2018. I find that civic education courses are associated with higher rates of external efficacy among white youth, but not for black and Latinx youth. Contrastingly, civic education courses appear to increase acts of public voice among black and Latinx respondents, but not for their white peers. Rather than viewing civic education courses as a panacea for low rates of youth political participation, scholars and policymakers should pay closer attention to the ways in which the content of civic education courses contributes to heterogeneous effects across racial and ethnic groups.
Petrogenesis and metallogenic potential of the Wulanba granite, southern Great Xing’an Range, NE China: constraints from whole-rock and apatite geochemistry
Authors: Liu Yuan , Jiang Si-Hong , Bagas Leon , Chen Chun-Liang , Han Ning , Wan Yun-Yang
Published: November 2019

The Wulanba granite, consisting of biotite monzogranite and syenogranite, is located in the southern part of the Great Xing’an Range, NE China. Whole-rock major- and trace-element geochemistry suggests the Wulanba granite is a high-K–shoshonitic, slightly peraluminous and highly differentiated I-type granite. The Sr–Nd–Hf isotopes indicate that it originated from partial melting of juvenile crust derived from the depleted mantle with a minor input of old crust. The relatively young T2DM and tDM2 ages indicate it was most likely derived from a Late Neoproterozoic to Early Palaeozoic source. We have demonstrated that the biotite monzogranite is the ore-related intrusion of the Haobugao Zn–Fe mineralization based on the following geological, geochronological and geochemical evidence: (1) the chalcopyrite/pyrite in the biotite monzogranite and the continuous mineralization of drill core ZK2508; (2) the consistence of the emplacement age of the biotite monzogranite (~141–140/138 Ma) with the skarn mineralization age (~142 Ma); and (3) the presence of rich ore-forming elements (Fe–Zn–Cu) in the biotite monzogranite, and the similar Pb compositions of the sulfides from the Haobugao deposit and the biotite monzogranite. Compared to the barren syenogranite, the fertile biotite monzogranite is more oxidized, while the edges of the apatite grains in the biotite monzogranite are more oxidized than the centres. The average F/Cl ratio of the fertile biotite monzogranite (~123.45) is much higher than that of the barren syenogranite (~73.98). We conclude that these differences reflect unique geochemical signatures, and the geochemical composition of the apatite can be used to infer the economic potential of granites.
Addressing the ‘Tower of Babel’ of pesticide regulations: an ontology for supporting pest-control decisions
Authors: Goldstein A. , Fink L. , Raphaeli O. , Hetzroni A. , Ravid G.
Published: November 2019

Farmers, who have to decide which pesticide to use against a particular crop-damaging pest, need to take into account country-specific regulations (e.g. permitted levels of pesticide residues), application instructions and financial considerations. The fact that these data are stored in different locations, sometimes using different terminology or different languages, makes it difficult to gather these data and requires that farmers are familiar with the variety of terms used, which consequently hampers the efficiency and effectiveness of the decision process. To overcome these challenges, a Web application for pest control is proposed to facilitate the integration of information coming from different Internet sources and representing different terminologies by using an ontology. The application is based on a pest-control ontology (formal representations of domain knowledge that can be interpreted by computers) that accounts for various pesticide regulations of different countries to which the crop is exported. In recent years, ontologies have become a major tool for domain knowledge representation and a core component of many knowledge management systems, decision support systems and other intelligent systems, inter alia, in the context of agriculture. The pest-control ontology developed in the current research includes pest-control concepts that have yet to be covered by existing ontologies. It is demonstrated in the specific case of pepper in Israel. The ontology is expressed using Web Ontology Language (OWL) and thus can be shared on the Web and reused by other ontologies and systems. In addition, a comprehensive method for developing and evaluating agricultural ontologies is presented.
Energy-Optimal Motion Trajectory of an Omni-Directional Mecanum-Wheeled Robot via Polynomial Functions
Authors: Xie Li , Stol Karl , Xu Weiliang
Published: November 2019

The Mecanum wheel is one of the practical omni-directional wheel designs in industry, especially for heavy-duty tasks in a confined floor. An issue with Mecanum-wheeled robots is inefficient use of energy. In this study, the robotic motion trajectories are optimized to minimize the energy consumption, where a robotic path is expressed in polynomial functions passing through a given set of via points, and a genetic algorithm is used to find the polynomial’s coefficients being decision variables. To attempt a further reduction in the energy consumption, the via points are also taken as decision variables for the optimization. Both simulations and experiments are conducted, and the results show that the optimized trajectories result in a significant reduction in energy consumption, which can be further lowered when the via points become decision variables. It is also found that the higher the order of the polynomials the larger the reduction in the energy consumption.
Three Typological Differences Between the North and the West Germanic DPs
Authors: Roehrs Dorian
Published: November 2019

This paper discusses three typological differences between the North Germanic DP and the West Germanic DP. While North Germanic has suffixal definite articles leading to cases of double definiteness, weak adjective endings regulated by definiteness, and doubly-filled definite DPs, West Germanic does not. These three properties cluster together in that they all have to do with definiteness. It is claimed that they can be subsumed under one more general difference. Assuming various subcomponents of definiteness, it is proposed that these components originate low in the structure. North Germanic arranges these components into several individual feature bundles. Some of these bundles move to D, while others remain lower in the structure. Consequently, definiteness components are spelled out separately in different positions. In contrast, West Germanic involves one complex feature bundle containing all definiteness components. In this language family, all of the components move to D as one bundle and, as a consequence, they are all spelled out as one determiner.
SLS/BIALL Academic Law Library Survey 2017/2018
Authors: Gee David
Published: November 2019

This is the latest report analysing the results of the annual Academic Law Library Survey that is jointly sponsored by the Society of Legal Scholars (SLS) and the British and Irish Association of Law Librarians (BIALL). It has been compiled and written by David Gee, Librarian at the Institute of Advanced Legal Studies, a part of the School of Advanced Study at the University of London.
Climate Litigation in Financial Markets: A Typology
Authors: Solana Javier
Published: November 2019

Over the past few years, the number of climate cases being filed against corporations and public authorities around the world has been on the rise. Aware of the central role of finance in economic development, the financial sector has remained vigilant. Traditionally, climate litigation in financial markets had been rare, but that seems to be changing: in 2018 there were more cases filed than in any previous year. The development of existing and forthcoming private and public sector initiatives with the aim of promoting sustainable finance may usher in even greater numbers in the next few years. This article provides the first systematic overview of climate cases in financial markets and introduces a typology to classify this type of climate case. This classification reveals common issues across different financial systems and raises questions for further enquiry that define a new research area within the emerging literature on climate litigation.
Lessons from the Terror: Soviet Prosecutors and Police Violence in Molotov Province, 1942 to 1949
Authors: Rebitschek Immo
Published: November 2019

This paper examines the role of state prosecutors in the Stalinist dictatorship by analyzing the conflict between the Procuracy and the police in the Molotov region in the 1940s. This regional case study exemplifies how a Soviet prosecutor, by professional conviction and motivated by personal experience from the Great Terror, engaged in a daily struggle against arbitrariness, imprecise legal work, and police brutality, pressuring police authorities to prosecute their own officials. The paper demonstrates how since 1938 the procuracy articulated and defended (sometimes successfully) the principle of a justice system based on rules, even though these rules were used for the purpose of repression. This eventually enabled post-Stalinist transformation.
Die Advanced Practice Nurse (APN) in der gynäkologischen Onkologie
Authors: Kobleder Andrea , Mayer Hanna , Senn Beate
Published: November 2019

Zusammenfassung. Hintergrund: Die Advanced Practice Nurse (APN) kann für Frauen mit einer gynäkologischen Krebserkrankung eine bedeutsame Unterstützung im Behandlungsprozess darstellen. In Österreich und der Schweiz steht die APN-Entwicklung allerdings erst am Anfang und es fehlt an systematisch entwickelten Konzepten. Fragestellung: Welche Merkmale sollte ein auf wissenschaftlichen Erkenntnissen basierendes APN-Konzept in der gynäkologischen Onkologie im Versorgungskontext Österreich und Schweiz beinhalten? Methode: Die Entwicklung des Konzepts erfolgte mit Hilfe einer Matrix, die basierend auf dem PEPPA plus-Framework entstand, Inhalte des Nursing Role Effectiveness Models (NREM) enthielt und Daten aus vier vorangegangenen Einzelstudien zusammenführte. Dreizehn Expertinnen und Experten aus Pflege und Medizin waren an der Vernehmlassung des Konzepts beteiligt. Ergebnisse: Unterteilt in Struktur-, Prozess- und Outcome-Kriterien beschreibt das Konzept zentrale Inhalte der APN-Rolle in der gynäkologischen Onkologie im Versorgungskontext Österreich und Schweiz. Zusätzlich werden die Beziehungen zwischen Struktur-Prozess, Struktur-Outcome und Prozess-Outcome dargestellt. Schlussfolgerungen: Das in dieser Studie entwickelte Konzept bietet eine Grundlage zur (1) weiteren Ausgestaltung einer APN-Rollenbeschreibung in der gynäkologischen Onkologie auf institutioneller Ebene sowie (2) curricularen Entwicklung entsprechender Studiengänge. Durch die gemeinsame Basis kann eine Harmonisierung der APN-Rolle im Versorgungskontext Österreich und Schweiz gefördert werden.
Evolution of the Thermohaline Structure of One Agulhas Ring Reconstructed from Satellite Altimetry and Argo Floats
Authors: Laxenaire R. , Speich S. , Stegner A.
Published: November 2019

The transfer of Indian Ocean thermocline and intermediate waters into the South Atlantic via the Agulhas leakage is generally believed to be primarily accomplished through mesoscale eddy processes, essentially anticyclones known as Agulhas Rings. Here we take advantage of a recent eddy tracking algorithm and Argo float profiles to study the evolution and the thermohaline structure of one of these eddies over the course of 1.5 years (May 2013–November 2014). We found that during this period the ring evolved according to two different phases: During the first one, taking place in winter, the mixing layer in the eddy deepened significantly. During the second phase, the eddy subsided below the upper warmer layer of the South Atlantic subtropical gyre while propagating west. The separation of this eddy from the sea surface could explain the decrease in its surface signature in satellite altimetry maps, suggesting that such changes are not due to eddy dissipation processes. It is a very large eddy (7.1×1013 m3 in volume), extending, after subduction, from a depth of 200–1,200 m and characterized by two mode water cores. The two mode water cores represent the largest eddy heat and salt anomalies when compared with the surrounding. In terms of its impact over 1 year, the north‐westward propagation of this long‐lived anticyclone induces a transport of 2.2 Sv of water, 0.008 PW of heat, and 2.2×105 kg s−1 of salt. These results confirm that Agulhas Rings play a very important role in the Indo‐Atlantic interocean exchange of heat and salt.
Paleomagnetic Evidence for 25–15 Ma Crust Fragmentation of North Indochina (23–26°N): Consequence of Collision With Greater India NE Corner?
Authors: Speranza Fabio , Pellegrino Alessandra G. , Zhang Bo , Maniscalco Rosanna , Chen Siyu , Hernandez‐Moreno Catalina
Published: November 2019

The Cenozoic deformation of SE Asia is classically related to India‐Asia collision and Tibet Plateau rise, supposedly resulting in the southeastward drift of lithospheric blocks bounded by strike‐slip faults with displacements in the order of 1,000 km. Here we report on the paleomagnetism of 44 Triassic‐Cretaceous red bed sites from the northern Simao, Chuandian, and Lanping “blocks,” along both sides of the Ailao Shan‐Red River shear zone (north Indochina). In the Simao domain, remagnetization predates folding and subsequent 48–70° clockwise rotation of three 2–5 km wide subblocks separated by two unrotated blocks. A primary magnetization component from the Lanping domain center suggests variably clockwise rotated (up to 95° ± 24°) sites, interrupted by a 2–6 km wide block that is rotated counterclockwise by 27° ± 6°. Thus, the Lanping and Simao “blocks” are far from being rigid, being made of a mosaic of independently deforming subblocks, whose kinematics and association with documented tectonics are speculative. It is unclear whether both folding and widespread remagnetization were synchronous or diachronous across north Indochina, but (considering previously published results) strike‐slip activity along major shear zones, remagnetization, rotations, and crustal shortening overlapped within the 32–15 Ma time window, thus were likely genetically related. As opposed to previous models, we suggest that in early to mid‐Cenozoic times, north Indochina was under the influence of oblique Neo‐Tethys subduction. Collision between the NE corner of Greater India and Indochina at ~30 Ma yielded ENE‐WSW shortening and strike‐slip reactivation of preexisting faults, in turn fragmenting the crust into small, independently rotating, blocks.
Secular Variation of the Intensity of the Geomagnetic Field in Mexico During the First Millennium BCE
Authors: Hervé Gwenaël , Perrin Mireille , Alva‐Valdivia Luis M. , Rodríguez‐Trejo Alejandro , Hernández‐Cardona Arnaldo , Córdova Tello Mario , Meza Rodriguez Carolina
Published: November 2019

In Western Eurasia, the first millennium BCE is characterized by the fastest secular variation of the Earth Magnetic Field observed over the last millennia and by a geomagnetic anomaly centered on the Middle East. On the global scale, the variation of the dipolar field during this period remains poorly constrained because of the lack of data in other geographical areas. Here, we presented 23 new mean archaeointensity data on ceramic sherds dated between 1500 BCE and 200 CE from Chalcatzingo archaeological site in Central Mexico. Archaeointensities were determined using the classical Thellier‐Thellier protocol with corrections for TRM anisotropy and cooling rate effects. Our work doubles the number of high‐quality archaeointensity data in Mexico during the considered period. Using a Bayesian approach, a new secular variation curve was calculated at Mexico City between 1500 BCE and 200 CE after selection of Mexican archaeointensity data. After a period of oscillations of the intensity between 20 and 40 μT from 1500 to 300 BCE, the curve shows a large maximum `~65 μT in the second century BCE. The corresponding VADM varied between ~4.0 and ~11.0 × 1022 Am2, which highlights further that the intensity of the geomagnetic field could vary at regional scale over a larger range as previously thought. However, this amplitude variation may be overestimated, as it does not take into account the fast directional variation observed at this time.
Thank You to Our 2018 Peer Reviewers
Authors: Rajaram Harihar , Diffenbaugh Noah , Camargo Suzana , Cardenas M. Bayani , Carey Rebecca , Cobb Kim , Cory Rose , Cronin Meghan , Dombard Andrew , Donohue Kathleen , Flesch Lucy , Giannini Alessandra , Hayes Gavin , Hogg Andrew , Ilyina Tatiana , Ivanov Valeriy , Jacobsen Steven , Korte Monika , Lu Gang , Morlighem Mathieu , Magnusdottir Gudrun , Newman Andrew , Opher Merav , Passalacqua Paola , Patricola Christina , Ritsema Jeroen , Sprintall Janet , Su Hui , Thornton Joel , Williams Paul , Yau Andrew
Published: November 2019

On behalf of the journal, AGU, and the scientific community, the Editors would like to sincerely thank those who reviewed manuscripts for Geophysical Research Letters in 2018. The hours reading and commenting on manuscripts not only improves the manuscripts but also increases the scientific rigor of future research in the field. We particularly appreciate the timely reviews, in light of the demands imposed by the rapid review process at Geophysical Research Letters. With the revival of the “major revisions” decisions, we appreciate the reviewers' efforts on multiple versions of some manuscripts. Many of those listed below went beyond and reviewed three or more manuscripts for our journal, and those are indicated in italics. In total, 4,484 referees contributed to 7,557 individual reviews in journal. Thank you again. We look forward to the coming year of exciting advances in the field and communicating those advances to our community and to the broader public.
Delayed and Sustained Remote Triggering of Small Earthquakes in the San Jacinto Fault Region by the 2014 Mw 7.2 Papanoa, Mexico Earthquake
Authors: Li Bo , Ghosh Abhijit , Mendoza Manuel M.
Published: November 2019

We apply a move max matched‐filter method to detect heightened seismicity triggered in the San Jacinto fault (SJF) zone, by the 2014 Mw 7.2 Papanoa, Mexico earthquake. The move max matched filter detects 5.4 and 1.7 times the number of earthquakes in the Southern California Seismic Network catalog and those detected by the matched‐filter method, respectively. The seismicity rate increases significantly ~3.5 hr after the passage of the teleseismic waves and persists above the background level for about 1 week. This observation of delayed triggering may imply that dynamic stresses had initiated a time‐dependent advance to failure or a secondary process. A highly active triggered patch is located ~10 km west of the SJF near Anza, on a previously unmapped fault. Focal mechanisms and a best fit plane suggest a normal fault perpendicular to the SJF. The unmapped fault may indicate higher seismic hazard in the surrounding areas if a large earthquake nucleated around the Anza seismic gap.
Acceleration of Ocean Acidification in the Western North Pacific
Authors: Ono Hisashi , Kosugi Naohiro , Toyama Katsuya , Tsujino Hiroyuki , Kojima Atsushi , Enyo Kazutaka , Iida Yosuke , Nakano Toshiya , Ishii Masao
Published: November 2019

Because annual anthropogenic CO2 emissions have grown rapidly over the past decades, there is a concern that anthropogenic CO2 invasion into the ocean may also have caused the rate of ocean acidification to increase. Here, we report the decadal and longer‐term variability in the rates of change of inorganic carbon variables since the early 1980s in surface seawaters of various oceanic regions along the 137°E repeat line in the western North Pacific. In the subtropical frontal zone, we found that the mean rate of acidification tracked the acceleration of the atmospheric CO2 increase; during 2008–2017, the rate of acidification was 30% faster than during 1983–2017. In the Kuroshio Recirculation and tropical zone, acidification trends were clear, but the trends were modulated by decadal variability associated with temporal variability in regional ocean circulation.
Lower Crustal Heterogeneity Beneath the Northern Tibetan Plateau Constrained by GPS Measurements Following the 2001 Mw7.8 Kokoxili Earthquake
Authors: Liu Shaozhuo , Xu Xiwei , Klinger Yann , Nocquet Jean‐Mathieu , Chen Guihua , Yu Guihua , Jónsson Sigurjón
Published: November 2019

We use GPS measurements across the Xidatan segment of the Kunlun fault in the Tibetan Plateau to investigate the surface deformation following the 2001 Mw 7.8 Kokoxili earthquake. We find significant postseismic deformation during the period 2007–2015, characterized by an asymmetric shear across the 2001 rupture, with average velocities reaching ~10 mm/year about 30–45 km south of the coseismic rupture. We also find that the postseismic transients diffused away from the coseismic rupture through time, with a shift of the maximum transient rates from ~20–30 km south of the rupture in 2001–2002 to ~30–45 km in 2007–2015. Viscoelastic relaxation is the dominant physical process during the period 2007–2015. The estimated effective viscosity of the lower crust beneath the Songpan‐Ganzi terrane is 2 × 1018–3 × 1018Pa s from the 2001–2002 data, and it has increased to ~2 × 1019Pa s for the period 6 to 14 years after the event. The large asymmetry in the postseismic deformation field indicates a laterally heterogeneous lower crust beneath the northern Tibetan Plateau. Viscoelastic relaxation models show that the viscosity of the lower crust beneath the Qaidam basin is ~2 and ~4 times larger than the viscosity of the lower crust beneath the Songpan‐Ganzi terrane in 2001–2002 and 2007–2015, respectively. Based on these data and results from previous studies, we postulate that the Kunlun fault itself is not the unique rheological boundary and that additional domains with viscosity increasing from the Qiangtang terrane to the Qaidam basin appear to be required.
Prolonged Fluvial Activity From Channel‐Fan Systems on Mars
Authors: Stucky de Quay Gaia , Kite Edwin S , Mayer David P.
Published: November 2019

Alluvial fans on Mars, which are primarily sourced from erosional alcoves incised into crater rims, record a period of increased surface runoff which ended >1 Ga. However, we lack quantitative constraints on the frequency and duration of river‐forming processes and the climatic conditions that accompanied these long‐term habitable episodes. Here we use bedrock erosion and sediment transport models to show that the cumulative time span of wet activity (i.e., nonzero erosion and deposition) was between 100 years to 1 Myr excluding dry years. We use Context Camera (CTX) digital elevation models to compile a data set of >200 channels upstream of depositional fans and determine key fluvial geometry metrics. Results from calculating Mars stream power parameters are compared to great escarpment channels and globally distributed bedrock rivers on Earth. Although Martian channel profile morphologies fall within the range of those on Earth, they are slightly less concave‐up (concavity index,
) and steeper for a given drainage area (reference steepness index,
, for reference drainage area, Ar = 1 ×107 m2). Timescales depend strongly on poorly constrained variables such as erodability and grain size. Channel morphologies, intermittencies, spatial distributions, and orientations collectively suggest an arid climate and a source from snowmelt on steep crater rims, possibly from obliquity‐paced insolation variations or orographic accumulation. Derived timescales are consistent with erosion rates and intermittencies observed in arid environments on Earth and do not support short‐lived or catastrophic triggers for the warm climate conditions (such as impacts or individual volcanic eruptions).
Through the Thick and Thin: New Constraints on Mars Paleopressure History 3.8 – 4 Ga from Small Exhumed Craters
Authors: Warren A. O. , Kite E. S. , Williams J.‐P. , Horgan B.
Published: November 2019

Mars' climate history depends in part on its atmospheric pressure evolution, but most existing constraints on atmospheric pressure are indirect. Thin atmospheres allow small objects to reach the surface and form impact craters; therefore, ancient impact craters can constrain past atmospheric pressure. To identify ancient craters preserved in sedimentary rocks and exhumed by wind erosion, we use HiRISE orthoimages, anaglyphs, and digital terrain models (DTMs). We compare measured crater populations from two sites to predictions from an atmosphere‐impactor interaction model for atmospheres of different pressures. Our upper limits on continuous atmospheric pressure are 1.9±0.1 bar around 4 Ga and 1.5±0.1 bar at 3.8±0.2 Ga. We demonstrate that atmospheric pressure cannot have been continuously above these upper limits. During the interval 3.8±0.2 Ga, our crater counts require that atmospheric pressure was less than 5% of Earth's modern pressure for at least 104 yrs, or at higher pressure for a correspondingly longer duration of time (at least 105−106 years at 1.5 bar for our Mawrth phyllosilicates and Meridiani Planum data, respectively). Therefore, atmospheric pressure around 4 Ga was either continuously 1.9±0.1 bar or varied between higher (>1.9 bar) and lower (<1.9 bar) pressures. Similarly, atmospheric pressure at 3.8±0.2 Ga was either continuously 1.5±0.1 bar, or varied between higher (>1.5 bar) and lower (<1.5 bar) pressures. Finally, we synthesize all available paleopressure estimates for early Mars to constrain a 2‐component model of Mars' long‐term atmospheric pressure evolution. In our model, atmospheric pressures <1 bar early in Mars' history best fit existing paleopressure constraints.
The Development of an Atmospheric Aerosol/Chemistry‐Climate Model, BCC_AGCM_CUACE2.0, and Simulated Effective Radiative Forcing of Nitrate Aerosols
Authors: An Qi , Zhang Hua , Wang Zhili , Liu Yi , Xie Bing , Liu Qianxia , Wang Zaizhi , Gong Sunling
Published: November 2019

This study developed a next‐generation atmospheric aerosol/chemistry‐climate model, the BCC_AGCM_CUACE2.0. Then, the performance of the model for nitrate was evaluated, and the nitrate direct radiative forcing (DRF) and effective radiative forcing (ERF) due to aerosol‐radiation interactions were simulated for the present day (2010), near‐term future (2030), and middle‐term future (2050) under the Representative Concentration Pathway 4.5, 6.0, and 8.5 scenarios relative to the preindustrial era (1850). The model reproduced the distributions and seasonal changes in nitrate loading well, and simulated surface concentrations matched observations in Europe, North America, and China. Current global mean annual loading of nitrates was predicted to increase by 1.50 mg m−2relative to 1850, with the largest increases occurring in East Asia (9.44 mg m−2), Europe (4.36 mg m−2), and South Asia (3.09 mg m−2). The current global mean annual ERF of nitrates was −0.28 W m−2relative to 1850. Due to global reductions in pollutant emissions, the nitrate ERF values were predicted to decrease to −0.17, −0.20, and −0.24 W m−2in 2030 and −0.07, −0.18, and −0.19 W m−2in 2050 for Representative Concentration Pathway 4.5, 6.0, and 8.5 relative to 1850, respectively. Although global mean nitrate values showed a declining trend, future nitrate loading remained high in East Asia and South Asia.
A Steady‐State Model for the Relationship Between Humidity, Instability, and Precipitation in the Tropics
Authors: Singh Martin S. , Warren Robert A. , Jakob Christian
Published: November 2019

A simple steady‐state model for the thermodynamic structure of a convecting atmosphere under the influence of large‐scale dynamics is derived based on a bulk‐plume representation of convection. Given profiles of the large‐scale vertical velocity and convective mass flux, the model predicts the steady‐state temperature and environmental relative humidity profiles as a function of the convective entrainment rate and a parameter representing the importance of condensate reevaporation. The bulk‐plume model determines the environmental relative humidity through a balance between the moistening effect of convective detrainment and the drying effect of subsidence in the cloud environment. As the convective mass flux is increased, the importance of detrainment moistening increases, leading to a higher environmental relative humidity. Since the precipitation rate also increases with the convective mass flux, this leads to a steady state in which the precipitation is a strongly increasing function of environmental relative humidity. The bulk‐plume model also predicts that the atmospheric stability increases with large‐scale upward motion, with the tropospheric lapse rate being most unstable under large‐scale descent, when the environmental relative humidity is low. The above relationships are reproduced in a set of simulations with a cloud‐system resolving model (CRM) run to equilibrium with imposed large‐scale vertical velocity profiles. The results provide insight to the steady‐state limit of the well‐known problem of determining the relationships between large‐scale conditions and the convective state of the atmosphere.
Evaluation of CNRM Earth System Model, CNRM‐ESM2‐1: Role of Earth System Processes in Present‐Day and Future Climate
Authors: Séférian Roland , Nabat Pierre , Michou Martine , Saint‐Martin David , Voldoire Aurore , Colin Jeanne , Decharme Bertrand , Delire Christine , Berthet Sarah , Chevallier Matthieu , Sénési Stephane , Franchisteguy Laurent , Vial Jessica , Mallet Marc , Joetzjer Emilie , Geoffroy Olivier , Guérémy Jean‐François , Moine Marie‐Pierre , Msadek Rym , Ribes Aurélien , Rocher Matthias , Roehrig Romain , Salas‐y‐Mélia David , Sanchez Emilia , Terray Laurent , Valcke Sophie , Waldman Robin , Aumont Olivier , Bopp Laurent , Deshayes Julie , Éthé Christian , Madec Gurvan
Published: November 2019

This study introduces CNRM‐ESM2‐1, the Earth system (ES) model of second generation developed by CNRM‐CERFACS for the sixth phase of the Coupled Model Intercomparison Project (CMIP6). CNRM‐ESM2‐1 offers a higher model complexity than the Atmosphere‐Ocean General Circulation Model CNRM‐CM6‐1 by adding interactive ES components such as carbon cycle, aerosols, and atmospheric chemistry. As both models share the same code, physical parameterizations, and grid resolution, they offer a fully traceable framework to investigate how far the represented ES processes impact the model performance over present‐day, response to external forcing and future climate projections. Using a large variety of CMIP6 experiments, we show that represented ES processes impact more prominently the model response to external forcing than the model performance over present‐day. Both models display comparable performance at replicating modern observations although the mean climate of CNRM‐ESM2‐1 is slightly warmer than that of CNRM‐CM6‐1. This difference arises from land cover‐aerosol interactions where the use of different soil vegetation distributions between both models impacts the rate of dust emissions. This interaction results in a smaller aerosol burden in CNRM‐ESM2‐1 than in CNRM‐CM6‐1, leading to a different surface radiative budget and climate. Greater differences are found when comparing the model response to external forcing and future climate projections. Represented ES processes damp future warming by up to 10% in CNRM‐ESM2‐1 with respect to CNRM‐CM6‐1. The representation of land vegetation and the CO2‐water‐stomatal feedback between both models explain about 60% of this difference. The remainder is driven by other ES feedbacks such as the natural aerosol feedback.