bluuebunny/crossref_metadata_2025 huggingface dataset:
NGI works with UK firm to develop enhanced water filtration system based on graphene's unique properties
Authors: Atkinson Simon
Published: August 2019

In the UK, the National Graphene Institute at the University of Manchester is working with a manufacturer of portable and reusable water filtration systems on a project that again highlights the unique properties of graphene and the way in which this material can be used to enhance water filtration.
Limit theorems for some skew products with mixing base maps
Authors: HAFOUTA YEOR
Published: August 2019

We obtain a central limit theorem, local limit theorems and renewal theorems for stationary processes generated by skew product maps$T(\unicode[STIX]{x1D714},x)=(\unicode[STIX]{x1D703}\unicode[STIX]{x1D714},T_{\unicode[STIX]{x1D714}}x)$together with a$T$-invariant measure whose base map$\unicode[STIX]{x1D703}$satisfies certain topological and mixing conditions and the maps$T_{\unicode[STIX]{x1D714}}$on the fibers are certain non-singular distance-expanding maps. Our results hold true when$\unicode[STIX]{x1D703}$is either a sufficiently fast mixing Markov shift with positive transition densities or a (non-uniform) Young tower with at least one periodic point and polynomial tails. The proofs are based on the random complex Ruelle–Perron–Frobenius theorem from Hafouta and Kifer [Nonconventional Limit Theorems and Random Dynamics. World Scientific, Singapore, 2018] applied with appropriate random transfer operators generated by$T_{\unicode[STIX]{x1D714}}$, together with certain regularity assumptions (as functions of $\unicode[STIX]{x1D714}$) of these operators. Limit theorems for deterministic processes whose distributions on the fibers are generated by Markov chains with transition operators satisfying a random version of the Doeblin condition are also obtained. The main innovation in this paper is that the results hold true even though the spectral theory used in Aimino, Nicol and Vaienti [Annealed and quenched limit theorems for random expanding dynamical systems.Probab. Theory Related Fields162(2015), 233–274] does not seem to be applicable, and the dual of the Koopman operator of$T$(with respect to the invariant measure) does not seem to have a spectral gap.
Influence of measurement errors on networks: Estimating the robustness of centrality measures
Authors: Martin Christoph , Niemeyer Peter
Published: August 2019

Most network studies rely on a measured network that differs from the underlying network which is obfuscated by measurement errors. It is well known that such errors can have a severe impact on the reliability of network metrics, especially on centrality measures: a more central node in the observed network might be less central in the underlying network. Previous studies have dealt either with the general effects of measurement errors on centrality measures or with the treatment of erroneous network data. In this paper, we propose a method for estimating the impact of measurement errors on the reliability of a centrality measure, given the measured network and assumptions about the type and intensity of the measurement error. This method allows researchers to estimate the robustness of a centrality measure in a specific network and can, therefore, be used as a basis for decision-making. In our experiments, we apply this method to random graphs and real-world networks. We observe that our estimation is, in the vast majority of cases, a good approximation for the robustness of centrality measures. Beyond this, we propose a heuristic to decide whether the estimation procedure should be used. We analyze, for certain networks, why the eigenvector centrality is less robust than, among others, the pagerank. Finally, we give recommendations on how our findings can be applied to future network studies.
From Myths to Markets
Authors: Carter Elizabeth
Published: August 2019

This article posits that institutionalized mythologies can create comparative production advantages. Myths shape collective identity, mobilize actors, and fundamentally reshape production dynamics. Myths are institutionalized in market rules, regulations and structures, leading to the reification of the myth. The myth functions as if it is true, not because it is true, but because it shapes the rules of production. Yet without the initial myth, specific production incentives—and even their institutional comparative advantages—would not exist. My theory integrates approaches from modernist historians (“imagined communities”) and economic sociologists (“imagined futures”) to explain how myths (“imagined histories”) shape contemporary market outcomes, using the example of the French wine market. This argument contributes to the historical institutionalist approach, which focuses on the historical power dynamics between competing groups and the present-day social and market consequence of their institutionalized solutions.
The association of maternal dietary folate intake and folic acid supplementation with small-for-gestational-age births: a cross-sectional study in Northwest China
Authors: Li Shanshan , Liu Danmeng , Zhang Ruo , Lei Fangliang , Liu Xin , Cheng Yue , Li Chao , Xiao Mengyao , Guo Leqian , Li Minmin , Zhang Binyan , Zhu Zhonghai , Shi Guoshuai , Liu Yezhou , Dang Shaonong , Yan Hong
Published: August 2019

The effect of maternal folate intake on small-for-gestational-age (SGA) births remains inconclusive. The present study aimed to investigate the associations of maternal folate intake from diet and supplements with the risk of SGA births using data from a cross-sectional study in Shaanxi Province of Northwest China. A total of 7307 women who were within 12 months (median 3; 10th–90th percentile 0–7) after delivery were included. Two-level models were adopted to examine the associations of folate (dietary folate, supplemental folic acid and total folate) intake with the risk of SGA births and birth weight Z score, controlling for a minimum set of confounders that were identified in a directed acyclic graph. Results showed that a higher supplemental folic acid intake during the first trimester was negatively associated with the risk of SGA births (≤60 d v. non-use: OR 0·80; 95 % CI 0·66, 0·96; >60 d v. non-use: OR 0·78; 95 % CI 0·65, 0·94; Ptrend = 0·010; per 10-d increase: OR 0·97; 95 % CI 0·95, 0·99). A higher total folate intake during pregnancy was associated with a reduced risk of SGA births (highest tertile v. lowest tertile: OR 0·77; 95 % CI 0·64, 0·94; Ptrend = 0·010; per one-unit increase in the log-transformed value: OR 0·81; 95 % CI 0·69, 0·95). A similar pattern was observed for the birth weight Z score. Our study suggested that folic acid supplementation during the first trimester and a higher total folate intake during pregnancy were associated with a reduced risk of SGA births.
Engaging Youths across the Education Divide: Is There a Role for Social Capital?
Authors: Tossutti Livianna
Published: August 2019

This study draws on the 2013 General Social Survey to investigate whether social capital is positively associated with the political participation and engagement of 15- to 24-year-old Canadians. It also assesses whether social capital can help overcome the participation gap between youths with different educational qualifications. Trust in family was the only social tie that was positively associated with the turnout of eligible voters in federal and municipal elections. Associational involvements and generalized trust in strangers were more frequently related to informal political activism and an interest in politics. Online social connections were unrelated to any measure of participation and engagement. Some forms of social capital can help address the marginalization of youths from formal and informal politics, but tertiary education is most closely associated with voting.
Learning from the Confessional in the Later Thirteenth Century: Contributions to Human Sexuality, Daily Life, and a Science of Nature
Authors: Resnick Irven M.
Published: August 2019

Implementation of the canons of the Fourth Lateran Council dramatically expanded the practice of auricular confession among laypeople. Although the Council's canons also insist upon the seal of confession in order to keep the content of confessions secret, thirteenth-century authorities differ over the boundaries of the seal. As a result, the “secrets” of confession are often revealed in at least general terms in order to provide preachers with entertaining exempla for moral or doctrinal instruction. What is revealed from confession not only provides a window onto medieval private lives, but it also provided confessors with information about human activities—especially sexual practices—that might otherwise be unavailable to them. With such information, learned confessors not only encouraged moral reform but also defended claims of Aristotelian biology on human nature and sexuality.
Women and Consistorial Discipline: The Case of Courthézon in the Early Seventeenth Century
Authors: Meyer Judith P.
Published: August 2019

This study seeks to contribute to a more nuanced understanding of both the Reformed church consistory and women's experience of the Reformation by examining the interactions between the Reformed church consistory and women in the small French town of Courthézon. For the period from 1617 to 1631, it analyzes how the consistory treated women in its exercise of discipline and how women in turn treated the consistory. It examines in-depth a number of cases of women summoned by the consistory for various offenses, including quarreling, dancing, marital and sexual relations, and absence from services. The interactions were complex and suggest that both male patriarchy and female agency were at work. Yet the consistory also treated the two sexes similarly in certain instances. Women demonstrated a remarkable capacity to ignore, negotiate with, and on occasion defy the consistory. One extraordinary woman rejected the consistory's authority altogether when pressed to reconcile. The cases also indicate that the process of consistorial discipline aided women by providing opportunities for them to represent and act for themselves. The consistory was guided by a desire to keep its minority community intact: it showed remarkable patience, forbearance, and a willingness to compromise in its efforts, and it consequently was usually successful.
Religion, Revolution, and the Dangers of Demagogues: The Basel “Troubles” (Wirren) and the Politics of Protestantism, 1830–1833
Authors: Purvis Zachary
Published: August 2019

In 1833, the Swiss city-republic of Basel separated into two distinct cantons. During the three-year period known as the “Troubles” (Wirren), landowners in the countryside, inspired by the French July Revolution of 1830, rebelled against the city government. The roots of the division, however, run deeper in Basel's religious and theological culture and also reflect the outgrowth of the German Confederation's “persecution of demagogues.” This article examines these neglected aspects of the cantonal division, showing the importance of Christianity, and the complex politics of Protestantism, in Europe's revolutionary century.
Music and Society in Late Colonial India: A Study of Esraj in Gaya
Authors: Roy Tirthankar
Published: August 2019

In the late nineteenth and early twentieth centuries, Indian classical music was in transition. Most readings of the transition stress the choices of the professional musicians, as these musicians and the institutions in which they functioned were caught up in political and economic movements such as nationalism and commercialization. This article studies a different type of transition: when a small-town professional group with a strong associational culture became musicians. This second process, standing in contrast to the received narratives, suggests novel lessons in the history of urban cultures during a time of change.
Effects of stocking density during the dry period on dairy cow physiology, metabolism and behaviour
Authors: Fujiwara Mayumi , Haskell Marie , Macrae Alastair , Rutherford Kenny
Published: August 2019

The effects of high stocking density during the dry period on dairy cow physiology, behaviour and welfare were investigated. Holstein Friesian cows (n = 48, calving over a seven month period) were dried-off 60 ± 4 d before their expected calving date, and allocated to either high (H) or low (L) stocking density groups. Cows were housed in cubicles from dry-off to 21 d before calving and then moved to straw yards until calving. In cubicle pens, H and L cows had 0.5 vs. 1.0 feed yokes/cow and 1.0 vs. 1.5 cubicles/cow, respectively, and in straw yards, 0.3 m vs. 0.6 m linear feed-face space and 6 m2vs. 12 m2 lying space, respectively. Video observations of feeding behaviour during the 3 h after feed delivery (3 d/week) and agonistic interactions at the feed-face during peak feeding (2 d/week) were made. Daily lying proportion was measured using an accelerometer device throughout the dry period. Concentrations of faecal glucocorticoid metabolites (FGCM) at dry-off, d7 and d35 after dry-off and d21 and d7 before calving and the change in energy metabolites (glucose, NEFA, BHB) from dry-off to d7 before calving were measured. H cows were less likely to start feeding within 5 min of feed delivery and spent less time feeding compared to L cows, but they engaged in displacements more frequently and spent more time standing in the feed alley. Irrespective of the treatment groups, FGCM concentrations significantly increased from dry-off to d7 after dry-off and remained higher during the dry period. Stocking density did not affect daily lying proportion, energy metabolites during the dry period and milk yield during subsequent lactation. This study found that whilst high stocking density during the dry period increased competition at the feed-face and altered feeding behaviour, it did not affect stress responses, energy metabolism or subsequent milk yield.
Spatio-temporal variation in rate of carbonate deposition by encrusting organisms in different reef microhabitats from Eastern Pacific coral reefs
Authors: Alvarado-Rodríguez J. F. , Nava H. , Carballo J. L.
Published: August 2019

Reef encrusting calcifiers (non-scleractinian species) constitute assemblages that participate in the carbon cycle at coral reefs. Despite their apparent secondary role in building the reef framework, they contribute to the reef consolidation binding sediments and inducing larval recruitment from other epilithic invertebrates. The contribution of encrusting calcifiers on reef accretion was examined by the assessment of their rate of carbonate deposition on four different simulated reef microhabitats using calcification accretion units (CAUs) during 12 months at Playa Las Gatas and Islote Zacatoso, two coral communities from the coast of the Mexican Pacific. Encrusting calcifiers from Playa Las Gatas, the most impacted site, showed a rate of carbonate deposition (mean ± SD) four times higher than at Islote Zacatoso (10.02 ± 3.22 g CaCO3m−2d−1vs2.48 ± 1.01 g CaCO3m−2d−1). Overall, the rate of carbonate deposition on surfaces protected from sedimentation and light was up to 1.8 times higher than on exposed ones (11.40 ± 4.35 g CaCO3m−2d−1vs6.18 ± 3.13 g CaCO3m−2d−1). Carbonate deposition by calcareous algae was higher on the well-lit exposed surfaces while filter-feeding invertebrates showed the major contribution on the shaded cryptic surfaces. Although rate of carbonate deposition by encrusting calcifiers seems to be lower than hermatypic corals, it seems to be relevant on coral reefs affected by anthropogenic impacts where coral calcification is low. Under global demise of coral reefs by environmental degradation and climate change, encrusting calcifiers may become relevant for the process of carbonate deposition.
Doctoring the Body and Exciting the Soul: Drugs and consumer culture in medieval and early modern Iran
Authors: KAZEMI RANIN
Published: August 2019

This article focuses on the development of early modern consumerism in a part of the Middle East that historians of consumer culture are yet to fully explore. Making use of a wide variety of unexplored and underexplored original sources, the article contends that early modern consumer culture in Iran was grounded deeply in the ever-widening patterns of exchange and use that had developed slowly over the course of the previous centuries. The discussion below takes the growing popular interest in a few key psychoactive substances as a useful barometer of the dynamics of mass consumption, and chronicles how the slow and ever-expanding use of alcohol, opium, and cannabis (or a cannabis-like product) in the medieval period led to the popularity of coffee, tobacco, older drugs, and still other commodities in the sixteenth and seventeenth centuries. The aim here is to use the history of drug culture as an entry point to scrutinize the emergence of early modern consumerism among the elites and the non-elites in both urban and rural areas of the Middle East. In doing so, this article reconstructs the cultural and social history of recreational drugs prior to and during the early modern period, and elucidates the socio-economic context that helped bring about a ‘psychoactive revolution’ in the Safavid state (1501–1736).
Corporate governance and democratic accountability: local state-owned enterprises in Norway
Authors: Klausen Jan Erling , Winsvold Marte
Published: August 2019

Transferring public service provision to state-owned enterprises (SOEs) raises concerns over accountability deficits. We argue that the governance of SOEs requires reconciliation of the accountability relations found in traditional models of public administration, and the normative structures of control and accountability developed in the world of private enterprises, commonly referred to as corporate governance. To this end, we propose a model for structuring accountability relations between SOEs and governmental owners. The model prescribes a distinction between the roles of elected representatives and top managers as “forums” for accountability concerning the governmental owner’s mission-related and non-mission-related preferences towards the SOE. The model’s relevance is tested empirically using data from a study of SOEs in Norway’s local government sector. The analysis indicates that accountability practices in line with the prescriptions of the model were associated with a heightened sense of control over the SOEs.
Grid Governance in China's Urban Middle-class Neighbourhoods
Authors: Tang Beibei
Published: August 2019

This article examines the so-called “grid governance” scheme, a widely used grassroots governance strategy implemented in urban China in recent years. Drawing on data collected in multiple cities from 2011 to 2016, it analyses in what ways, and to what extent, the state employs the grid governance scheme to resolve neighbourhood conflicts and reinforce governance in Chinese urban middle-class neighbourhoods. The findings highlight complex interactions under the scheme among the residents, the state and market actors in neighbourhood governance, including the resident volunteers, residents’ social groups, residents’ committees and property management companies. By coopting middle-class resident volunteers, maximizing the existing political influence of the retired urban elites, and establishing Party organizations in middle-class residential communities, the grid governance scheme has become a major vehicle for resident mobilization and conflict resolution, and a key governance mechanism to reinforce the Party's leadership in middle-class neighbourhoods.
PreDICT: a graphical user interface to the DICVOL14 indexing software program for powder diffraction data
Authors: Blanton Justin R. , Papoular Robert J. , Louër Daniel
Published: August 2019

A straightforward intuitive user-friendly compact graphical interface, PreDICT (Premier DICVOL Tool) has been developed to take full advantage of the new capabilities of the most recent version of the DICVOL14 Indexing Software. The latter, an updated version of DICVOL04, includes optimizations, e.g. for monoclinic and triclinic cases, a detailed review of the input data from the indexing solutions, cell centering tests, as well as the handling of a moderate number of impurity peaks. Among the most salient features of PreDICT, one can mention the ability (1) to use 2θnon-equistepped input 1D X-ray powder diffraction patterns as can be obtained from 2D detectors, (2) to strip laboratory data from itsKα2contribution when present, (3) to generate 2θequistepped output 1D X-ray powder diffraction patterns in both the “.XY” and “.GSA” formats. In addition, PreDICT allows for the following features: (1) full access to the native DICVOL14 input/output ASCII file system is retained, (2) for any selection of a DICVOL14 suggested unit cell, all predicted Bragg peaks up to a certain 2θMAXvalue are clearly displayed and indicated, thereby emphasizing the contribution of the unaccounted peaks (if any) to the 1D X-ray powder diffraction pattern under current investigation.
Do we know how scabies outbreaks in residential and nursing care homes for the elderly should be managed? A systematic review of interventions using a novel approach to assess evidence quality
Authors: Morrison E. J. , Middleton J. , Lanza S. , Cowen J. E. , Hewitt K. , Walker S. L. , Nicholls M. , Rajan-Iyer J. , Fletcher J. , Cassell J. A.
Published: August 2019

Currently no national guidelines exist for the management of scabies outbreaks in residential or nursing care homes for the elderly in the United Kingdom. In this setting, diagnosis and treatment of scabies outbreaks is often delayed and optimal drug treatment, environmental control measures and even outcome measures are unclear. We undertook a systematic review to establish the efficacy of outbreak management interventions and determine evidence-based recommendations. Four electronic databases were searched for relevant studies, which were assessed using a quality assessment tool drawing on STROBE guidelines to describe the quality of observational data. Nineteen outbreak reports were identified, describing both drug treatment and environmental management measures. The quality of data was poor; none reported all outcome measures and only four described symptom relief measures. We were unable to make definitive evidence-based recommendations. We draw on the results to propose a framework for data collection in future observational studies of scabies outbreaks. While high-quality randomised controlled trials are needed to determine optimal drug treatment, evidence on environmental measures will need augmentation through other literature studies. The quality assessment tool designed is a useful resource for reporting of outcome measures including patient-reported measures in future outbreaks.
Moral Risk and Humane Farming
Authors: Fuentes López Fayna
Published: August 2019

Humane farming, that is, a husbandry system where animals do not suffer, either during their lives, or at the time of their killing, has been advertised as an ethical alternative to the horrors of factory farming. Although it could be argued that such a system does not currently exist, we ought to determine whether this is a morally desirable end to strive for. My objective is to assess one of the utilitarian arguments used in the debate about humane farming. In particular, I am interested in whether we have risk-related reasons to argue against the implementation of this practice. I will argue, against de Lazari-Radek and Singer, that considerations of moral risk should lead us to reject the practice of humane farming. In doing so, I will engage with arguments dealing with both the badness of animal death and the value of coming into existence.
Transition from intravenous treprostinil to enteral selexipag in an infant with pulmonary arterial hypertension
Authors: Koo Rachel , Lo Jennifer , Bock Matthew J.
Published: August 2019

Selexipag is an enteral, selective prostacyclin IP receptor agonist approved for pulmonary hypertension in adults. There are few reports of its use in children and none in infants. We report the first transition of an infant (11.5 months, 8.6 kg) from intravenous treprostinil (40 ng/kg/minute) to enteral selexipag (400 mcg twice daily) with a good response and no adverse effects.
Sudden cardiac arrest in the field in an 18-year-old male athlete with Noonan syndrome: case presentation and 5-year follow-up
Authors: Petrin Ziva , Soffer Benjamin , Daniels Steven J.
Published: August 2019

We present a case of sudden cardiac arrest in the field with complete neurological recovery in an 18-year-old athlete with phenotypic Noonan syndrome. Evaluation revealed interventricular septal thickness of 18 mm without left ventricular outflow tract obstruction and no other identifiable structural, electrophysiologic, or genetic abnormality except isolated heterozygous variant for desmoplakin DSP variant p.Lys2103Glu, with unknown clinical significance.
CHIP-Family intervention to improve the psychosocial well-being of young children with congenital heart disease and their families: results of a randomised controlled trial
Authors: van der Mheen Malindi , Meentken Maya G. , van Beynum Ingrid M. , van der Ende Jan , van Galen Eugène , Zirar Anne , Aendekerk Elisabeth W.C. , van den Adel Tabitha P.L. , Bogers Ad J.J.C. , McCusker Christopher G. , Hillegers Manon H.J. , Helbing Willem A. , Utens Elisabeth M.W.J.
Published: August 2019

Objective:

Children with congenital heart disease and their families are at risk of psychosocial problems. Emotional and behavioural problems, impaired school functioning, and reduced exercise capacity often occur. To prevent and decrease these problems, we modified and extended the previously established Congenital Heart Disease Intervention Program (CHIP)–School, thereby creating CHIP-Family. CHIP-Family is the first psychosocial intervention with a module for children with congenital heart disease. Through a randomised controlled trial, we examined the effectiveness of CHIP-Family.

Methods:

Ninety-three children with congenital heart disease (age M = 5.34 years, SD = 1.27) were randomised to CHIP-Family (n = 49) or care as usual (no psychosocial care; n = 44). CHIP-Family consisted of a 1-day group workshop for parents, children, and siblings and an individual follow-up session for parents. CHIP-Family was delivered by psychologists, paediatric cardiologists, and physiotherapists. At baseline and 6-month follow-up, mothers, fathers, teachers, and the child completed questionnaires to assess psychosocial problems, school functioning, and sports enjoyment. Moreover, at 6-month follow-up, parents completed program satisfaction assessments.

Results:

Although small improvements in child outcomes were observed in the CHIP-Family group, no statistically significant differences were found between outcomes of the CHIP-Family and care-as-usual group. Mean parent satisfaction ratings ranged from 7.4 to 8.1 (range 0–10).

Conclusions:

CHIP-Family yielded high program acceptability ratings. However, compared to care as usual, CHIP-Family did not find the same extent of statistically significant outcomes as CHIP-School. Replication of promising psychological interventions, and examination of when different outcomes are found, is recommended for refining interventions in the future.

Trial registry

Dutch Trial Registry number NTR6063, https://www.trialregister.nl/trial/5780.
Ventricular tachycardia and chest pain due to foreign body in the pericardium caused by self-injurious behaviour
Authors: Yamamoto Hidenori , Fukasawa Yoshie , Kato Taichi
Published: August 2019

A 14-year-old girl suddenly developed ventricular tachycardia and severe chest pain during hospitalisation for trauma surgery. CT revealed a needle in the pericardium. Careful interview elicited that she had inserted the needle by herself, and Munchausen syndrome was diagnosed. This is the first report of ventricular tachycardia caused by a foreign body in a patient with Munchausen syndrome.
Recharge: a preliminary evaluation of an emotion regulation enhanced CBT-i intervention for insomnia in early adolescence
Authors: Byrne Luka , Donovan Caroline , Shiels Amy
Published: August 2019

Background:

Insomnia disorder in adolescence is prevalent, persistent and associated with adverse outcomes, including reduced quality of life. Cognitive behavioural therapy for insomnia (CBT-i) has shown promise as an effective treatment for adolescents. Recent research has highlighted the role of emotion regulation in insomnia, suggesting that the inclusion of emotion regulation techniques may enhance CBT-i.

Aims:

To evaluate the feasibility and preliminary effectiveness of a CBT-i treatment program for insomnia in early adolescence, augmented with emotion regulation strategies, using a case-series design.

Method:

Three participants (mean 11.67 years) completed the program that consisted of seven, weekly individual therapy sessions and parental participation. Participants monitored their sleep daily during the intervention, and insomnia diagnostic status and severity, use of emotion regulation strategies and quality of life were assessed at baseline, post-intervention and at 6-week follow-up.

Results:

At post-treatment, none of the participants met criteria for insomnia and all reported statistically reliable reductions in symptoms. Improvements were maintained at follow-up for two participants. Sleep onset latency was reduced and improvements in quality of life were evident. There were no changes in the use of emotion regulation strategies following treatment. Adolescents and parents reported high program satisfaction.

Conclusions:

This preliminary evaluation provides support for the effectiveness of the CBT-i program tested. However, given that emotion regulation did not change and yet improvements in sleep were evident, the usefulness of augmenting the program with emotion regulation strategies requires further evaluation.
Interhemispheric Meridional Circulation During Sudden Stratospheric Warming
Authors: Laskar Fazlul I. , McCormack John P. , Chau Jorge L. , Pallamraju Duggirala , Hoffmann Peter , Singh Ravindra P.
Published: August 2019

Although sudden stratospheric warming (SSW) is mainly a northern high‐latitude phenomena, there are several reports of a concomitant global dynamical response throughout the mesosphere and lower thermosphere. Published reports based on model simulations so far attributed such variabilities to changes in global circulation; however, there is no clear explanation of how all these regions are physically connected during SSW events. The present investigation uses wind observations from two ground‐based specular meteor radars over northern high latitudes and midlatitudes and global winds from a high‐altitude meteorological analysis system to characterize global mesospheric circulation anomalies for major SSW events during 2010 and 2013. During these events radar observations and the reanalysis winds exhibited strong southward winds over the two northern midlatitude and high‐latitude stations. By removing seasonal variability from the high‐altitude meteorological analyses, we show that these southward wind anomalies are indeed part of a larger global‐scale circulation, which gets set up during SSW and extend from the Northern pole to low‐latitude regions of Southern Hemisphere in the mesosphere and lower thermosphere altitudes. These results also offer a possible explanation of how low‐latitude ionospheric electrodynamics are influenced by the changes in the circulation set in during SSW at high latitudes.
Multipoint Field‐Aligned Current Estimates With Swarm
Authors: Blagau A. , Vogt J.
Published: August 2019

Field‐aligned currents (FACs) are a key component of the magnetosphere‐ionosphere system, providing the transfer of energy and momentum between the distant collision‐free magnetospheric plasma and the collisional ionosphere. The European Space Agency's Swarm mission offers a unique opportunity to explore the FACs low‐altitude end by a broad range of single‐spacecraft and multispacecraft techniques. The present technical report demonstrates the application of dual‐ and three‐satellite FAC estimation methods based on the least squares approach, with the goal to enhance the use of Swarm data in exploring the high‐latitude current structures, beyond the official FAC product presently available to the end user. The dual‐satellite method presents some clear advantages since it provides stabler solutions, can be applied on a more general spacecraft configuration, and offers a robust error estimation scheme. Consequently, the method provides significantly more data near the singularity where the satellites' orbits intersect, allows FAC estimation with configurations that involves the upper Swarm satellite, or to fine tune the constellation geometry to the problem at hand. Similarly, the three‐satellite method, meant to be applied when Swarm forms a close configuration, brings additional valuable information, associated to a different (larger) scale. Moreover, it can estimate the FAC density with high time resolution when instantaneous measurements are used. The performance of the methods are thoroughly analyzed both on Swarm events and on simulated data, and the results are compared with other available methods. Particular emphasis is put on how different FAC estimation methods complement each other and provide consistent results.
Slow Slip Event On the Southern San Andreas Fault Triggered by the 2017 Mw8.2 Chiapas (Mexico) Earthquake
Authors: Tymofyeyeva Ekaterina , Fialko Yuri , Jiang Junle , Xu Xiaohua , Sandwell David , Bilham Roger , Rockwell Thomas K. , Blanton Chelsea , Burkett Faith , Gontz Allen , Moafipoor Shahram
Published: August 2019

Observations of shallow fault creep reveal increasingly complex time‐dependent slip histories that include quasi‐steady creep and triggered as well as spontaneous accelerated slip events. Here we report a recent slow slip event on the southern San Andreas fault triggered by the 2017 Mw8.2 Chiapas (Mexico) earthquake that occurred 3,000 km away. Geodetic and geologic observations indicate that surface slip on the order of 10 mm occurred on a 40‐km‐long section of the southern San Andreas fault between the Mecca Hills and Bombay Beach, starting minutes after the Chiapas earthquake and continuing for more than a year. Both the magnitude and the depth extent of creep vary along strike. We derive a high‐resolution map of surface displacements by combining Sentinel‐1 Interferometric Synthetic Aperture Radar acquisitions from different lines of sight. Interferometric Synthetic Aperture Radar‐derived displacements are in good agreement with the creepmeter data and field mapping of surface offsets. Inversions of surface displacement data using dislocation models indicate that the highest amplitudes of surface slip are associated with shallow (<1 km) transient slip. We performed 2‐D simulations of shallow creep on a strike‐slip fault obeying rate‐and‐state friction to constrain frictional properties of the top few kilometers of the upper crust that can produce the observed behavior.
Southern Hemisphere Atmospheric Blocking in CMIP5 and Future Changes in the Australia‐New Zealand Sector
Authors: Patterson Matthew , Bracegirdle Thomas , Woollings Tim
Published: August 2019

Many general circulation models fail to capture the observed frequency of atmospheric blocking events in the Northern Hemisphere; however, few studies have examined models in the Southern Hemisphere and those studies that have, have often been based on only a few models. To provide a comprehensive view of how the current generation of coupled general circulation models performs in the Southern Hemisphere and how blocking frequency changes under enhanced greenhouse gas forcing, we examine the output of 23 models from the Coupled Model Intercomparison Project Phase 5 (CMIP5). We find that models have differing biases during winter, when blocking occurrence is highest, though models underestimate blocking frequency south of Australia during summer. We show that models generally have a reduction in blocking frequency with future anthropogenic forcing, particularly in the Australia‐New Zealand sector with the number of winter blocked days reduced by about one third by the end of the 21st century.
Infragravity Wave Generation by Wind Gusts
Authors: Vrećica T. , Soffer R. , Toledo Y.
Published: August 2019

Through the analysis of propagation times of infragravity wave packets along ray paths, reanalysis data, and our field measurements in the East Mediterranean, we find evidence of deep water infragravity wave generation by offshore storms. We confirmed the results also using deep water pressure cell measurements in the Pacific. The known nearshore generation mechanism showed large discrepancies with the observed infragravity energy near Aogashima, Japan, during winter. A new model of deep water infragravity wave generation is developed, based on nonlinear interactions of wind wave triads with submesoscale wind oscillations. The observed underprediction of infragravity waves is resolved using this new gustiness‐based model. The new source term is found to be of importance during strong storms in the open ocean and underlines the importance of accounting for submesoscale wind oscillations in wind wave models.
Longitudinal Versus Lateral Estuarine Dynamics and Their Role in Tidal Stratification Patterns in Lower South San Francisco Bay
Authors: Hoang Olivia , Stacey Mark , Senn David , Holleman Rusty , MacVean Lissa
Published: August 2019

The dynamics of shoal‐channel estuaries require consideration of lateral gradients and transport, which can create significant intratidal variability in stratification and circulation. When the shoal‐channel system is strongly coupled by tidal exchange with mudflats, marshes, or other habitats, the gradients driving intratidal stratification variations are expected to intensify. To examine this dynamic, hydrodynamic data were collected from 27 January 2017 to 10 February 2017 in Lower South San Francisco Bay, a small subembayment fringed by extensive shallow vegetated habitats. During this deployment, salinity variations were captured through instrumentation of six stations (arrayed longitudinally and laterally) allowing for mechanisms of stratification creation and destruction to be calculated directly and compared with observed time variability of stratification at the central station. We present observation‐based calculations of longitudinal straining, longitudinal advection, lateral straining, and lateral advection. The time dependence of stratification was observed directly and calculated by summing measured longitudinal and lateral mechanisms. We found that the stratification dynamics switch between being longitudinally dominated during the middle of ebb and flood tides to being laterally dominated during the tidal transitions. This variability is driven by the interplay between tidally variable lateral density gradients and turbulent mixing. Relatively constant along‐estuary density gradients are differentially advected during flood and ebb tides, resulting in maximal lateral density gradients around tidal transitions. Simultaneous decrease in turbulent mixing at slack tides allows lateral density‐driven exchange to stratify the estuary channel at the slack after flood. At the end of ebb, barotropic forcing drives negatively buoyant shoal waters toward the channel.
Sensitivity of Coarse‐Scale Snow‐Free Land Surface Shortwave Albedo to Topography
Authors: Hao Dalei , Wen Jianguang , Xiao Qing , Lin Xingwen , You Dongqin , Tang Yong , Liu Qiang , Zhang Sisi
Published: August 2019

As a widespread landscape, rugged terrain significantly distorts the land surface albedo. Simply neglecting the topographic effects in the land surface albedo modeling and retrievals can lead to large biases and uncertainties over rugged terrain. In spite of gradually increasing research about the topographic effects on the albedo, the albedo sensitivities over rugged terrain to different variables remain unclear. In this paper, the sensitivities of coarse‐scale snow‐free albedo to topography were quantitatively investigated using the Moderate Resolution Imaging Spectroradiometer (MODIS) land surface albedo data and the variance‐based global sensitivity analysis based on a well‐established mechanistically‐based land surface albedo parameterized model over rugged terrain. The results based on the MODIS data revealed that MODIS land surface albedo over the Tibetan Plateau was highly sensitive to the topographic distribution, and the differences of the spatially averaged snow‐free black‐sky albedos over grasslands induced by different terrain could reach up to 0.10 in winter. The topographic effects on MODIS albedo are tightly relevant to the land cover type, solar illumination geometries, and vegetation characteristics. The global sensitivity analysis results underscored that topography was an important driving factor of the snow‐free albedo, and it accounted for more than 30% of the total variance, respectively. These results highlight the necessities for the topographic consideration in the land surface albedo modeling and retrievals even though the terrain is gentle (10–20°) and advance our understanding of the albedo sensitivities to different variables over rugged terrain, which will facilitate the improvement of land surface albedo parameterization in the land surface models.
Global change-driven use of onshore habitat impacts polar bear faecal microbiota
Authors: Watson Sophie E , Hauffe Heidi C , Bull Matthew J , Atwood Todd C , McKinney Melissa A , Pindo Massimo , Perkins Sarah E
Published: August 2019

The gut microbiota plays a critical role in host health, yet remains poorly studied in wild species. Polar bears (Ursus maritimus), key indicators of Arctic ecosystem health and environmental change, are currently affected by rapid shifts in habitat that may alter gut homeostasis. Declining sea ice has led to a divide in the southern Beaufort Sea polar bear subpopulation such that an increasing proportion of individuals now inhabit onshore coastal regions during the open-water period (‘onshore bears’) while others continue to exhibit their typical behaviour of remaining on the ice (‘offshore bears’). We propose that bears that have altered their habitat selection in response to climate change will exhibit a distinct gut microbiota diversity and composition, which may ultimately have important consequences for their health. Here, we perform the first assessment of abundance and diversity in the faecal microbiota of wild polar bears using 16S rRNA Illumina technology. We find that bacterial diversity is significantly higher in onshore bears compared to offshore bears. The most enriched OTU abundance in onshore bears belonged to the phylum Proteobacteria, while the most depleted OTU abundance within onshore bears was seen in the phylum Firmicutes. We conclude that climate-driven changes in polar bear land use are associated with distinct microbial communities. In doing so, we present the first case of global change mediated alterations in the gut microbiota of a free-roaming wild animal.
Tundra microbial community taxa and traits predict decomposition parameters of stable, old soil organic carbon
Authors: Hale Lauren , Feng Wenting , Yin Huaqun , Guo Xue , Zhou Xishu , Bracho Rosvel , Pegoraro Elaine , Penton C Ryan , Wu Liyou , Cole James , Konstantinidis Konstantinos T , Luo Yiqi , Tiedje James M , Schuur Edward A G , Zhou Jizhong
Published: August 2019

The susceptibility of soil organic carbon (SOC) in tundra to microbial decomposition under warmer climate scenarios potentially threatens a massive positive feedback to climate change, but the underlying mechanisms of stable SOC decomposition remain elusive. Herein, Alaskan tundra soils from three depths (a fibric O horizon with litter and course roots, an O horizon with decomposing litter and roots, and a mineral-organic mix, laying just above the permafrost) were incubated. Resulting respiration data were assimilated into a 3-pool model to derive decomposition kinetic parameters for fast, slow, and passive SOC pools. Bacterial, archaeal, and fungal taxa and microbial functional genes were profiled throughout the 3-year incubation. Correlation analyses and a Random Forest approach revealed associations between model parameters and microbial community profiles, taxa, and traits. There were more associations between the microbial community data and the SOC decomposition parameters of slow and passive SOC pools than those of the fast SOC pool. Also, microbial community profiles were better predictors of model parameters in deeper soils, which had higher mineral contents and relatively greater quantities of old SOC than in surface soils. Overall, our analyses revealed the functional potential of microbial communities to decompose tundra SOC through a suite of specialized genes and taxa. These results portray divergent strategies by which microbial communities access SOC pools across varying depths, lending mechanistic insights into the vulnerability of what is considered stable SOC in tundra regions.
Recurrent stress across life may improve cognitive performance in individual rats, suggesting the induction of resilience
Authors: Hadar Ravit , Edemann-Callesen Henriette , Hlusicka Elizabeth Barroeta , Wieske Franziska , Vogel Martin , Günther Lydia , Vollmayr Barbara , Hellweg Rainer , Heinz Andreas , Garthe Alexander , Winter Christine
Published: August 2019

Depressive symptoms are often accompanied by cognitive impairments and recurrent depressive episodes are discussed as a potential risk for dementia. Especially, stressful life events are considered a potent risk factor for depression. Here, we induced recurrent stress-induced depressive episodes over the life span of rats, followed by cognitive assessment in the symptom-free period. Rats exposed to stress-induced depressive episodes learned faster than control rats. A high degree of stress-induced depressive-like behavior early in the paradigm was a predictor of improved cognitive performance, suggesting induction of resilience. Subsequently, exposure to lorazepam prior to stress-induced depressive episodes and cognitive testing in a nonaversive environment prevented the positive effect. This indicates a beneficial effect of the stress-associated situation, with the existence of individual coping abilities. Altogether, stress may in some have a beneficial effect, yet for those individuals unable to tackle these aversive events, consecutive unpleasant episodes may lead to worse cognitive performance later in life.
Fecal microbiota transplantation alleviated Alzheimer’s disease-like pathogenesis in APP/PS1 transgenic mice
Authors: Sun Jing , Xu Jingxuan , Ling Yi , Wang Fangyan , Gong Tianyu , Yang Changwei , Ye Shiqing , Ye Keyue , Wei Dianhui , Song Ziqing , Chen Danna , Liu Jiaming
Published: August 2019

Alzheimer’s disease (AD) is the most common dementia in the elderly. Treatment for AD is still a difficult task in clinic. AD is associated with abnormal gut microbiota. However, little is known about the role of fecal microbiota transplantation (FMT) in AD. Here, we evaluated the efficacy of FMT for the treatment of AD. We used an APPswe/PS1dE9 transgenic (Tg) mouse model. Cognitive deficits, brain deposits of amyloid-β (Aβ) and phosphorylation of tau, synaptic plasticity as well as neuroinflammation were assessed. Gut microbiota and its metabolites short-chain fatty acids (SCFAs) were analyzed by 16S rRNA sequencing and1H nuclear magnetic resonance (NMR). Our results showed that FMT treatment could improve cognitive deficits and reduce the brain deposition of amyloid-β (Aβ) in APPswe/PS1dE9 transgenic (Tg) mice. These improvements were accompanied by decreased phosphorylation of tau protein and the levels of Aβ40 and Aβ42. We observed an increases in synaptic plasticity in the Tg mice, showing that postsynaptic density protein 95 (PSD-95) and synapsin I expression were increased after FMT. We also observed the decrease of COX-2 and CD11b levels in Tg mice after FMT. We also found that FMT treatment reversed the changes of gut microbiota and SCFAs. Thus, FMT may be a potential therapeutic strategy for AD.