bluuebunny/crossref_metadata_2025 huggingface dataset:
The introduction of the European Caucasotachea vindobonensis (Gastropoda: Helicidae) in North America, its origin and its potential range
Authors: Hausdorf Bernhard , Parr Matt , Shappell Laura J. , Oldeland Jens , Robinson David G.
Published: June 2021

We report the introduction of the central and eastern European helicid land snail Caucasotachea vindobonensis in North America. It was first recorded from Rensselaer County in the state of New York in 2015 by a community scientist. From 2016 to 2020, 14 additional occurrences in Rensselaer County, neighbouring Albany County and an imprecisely localized site in the Adirondack Mountains were recorded by community scientists. In 2020, the species was newly recorded at two sites in Schoharie County, NY, and at three sites in Québec, one of them approximately 700 km to the north of the initial record. Partial mitochondrial cox1 sequences from Rensselaer differ from an eastern Ukrainian haplotype only in a single substitution. Therefore, a Ukrainian origin for this introduction is likely, although not certain: the Rensselaer haplotype also differs in only two substitutions from a more widespread haplotype known from Ukraine, Hungary, Slovakia, Czechia, Serbia, and Bulgaria. An environmental niche model of the species based on occurrence data from central and eastern Europe indicated that a large region from the northern east coast to the midwestern United States is suitable for C. vindobonensis. The Canadian occurrences may indicate that the North American lineage is able to survive colder winters than predicted by the environmental niche model. Caucasotachea vindobonensis is not listed as a pest in Europe and it is unlikely to become an agricultural pest in North America as it prefers rotting plant material over living parts of plants, but its impact on native organisms can hardly be predicted.
Evapotranspiration and water availability response to climate change in the Middle East and North Africa
Authors: Ajjur Salah Basem , Al-Ghamdi Sami G.
Published: June 2021

Quantifying the impact of climate change on evapotranspiration is necessary for devising accurate water and energy budgets in light of global warming. Nevertheless, in the Middle East and North Africa (MENA), little has been done to bridge this gap. This study, then, implements Penman and Budyko approaches to climatic data retrieved from the sixth phase of the Coupled Model Intercomparison Project (CMIP6) to assess evapotranspiration and water availability evolutions through the twenty-first century. Outcomes reveal that the MENA region is indeed vulnerable to a surge in temperature, which can increase evapotranspiration losses and decrease water availability. Under the shared socioeconomic pathway (SSP2-4.5), the potential evapotranspiration (PET) has been projected to increase throughout the MENA region by up to 0.37 mm per year during the middle of the twenty-first century (2021–2050) and by up to 0.51 mm per year during the end of the twenty-first century (2071–2100). Meanwhile, the actual evapotranspiration (AET) has been projected to increase by up to 0.3 (~0.2) mm per year before 2050 (2100). The trends in both projections (PET and AET) are exaggerated under SSP5-8.5. The analysis predicted a shortage of water availability (precipitation—AET), which is alarming for most MENA regions. Relative to the reference period (1981–2010), the decline in annual water availability would reach 26 (62) mm by 2100 under SSP2-4.5 (SSP5-8.5). The rise in temperatures appears to be the principal reason for MENA and water availability responses. This study’s outcomes can facilitate accurate and realistic predictions related to evapotranspiration and water availability, which are key elements in not only managing water resources but also in devising effective climate change mitigation and adaptation plans.
Receptivity of inviscid modes in supersonic boundary layers to wall perturbations
Authors: Liu Yinhui , Dong Ming , Wu Xuesong
Published: June 2021

The present paper investigates the receptivity of inviscid first and second modes in a supersonic boundary layer to time-periodic wall disturbances in the form of local blowing/suction, streamwise velocity perturbation and temperature perturbation, all introduced via a small forcing slot on the flat plate. The receptivity is studied using direct numerical simulations (DNS), finite- and high-Reynolds-number approaches, which complement each other. The finite-Reynolds-number formulation predicts the receptivity as accurately as DNS, but does not give much insight to the detailed excitation process, nor can it explain the significantly weaker receptivity efficiency of the streamwise velocity and temperature perturbations relative to the blowing/suction. In order to shed light on these issues, an asymptotic analysis was performed in the limit of large Reynolds number. It shows that the receptivity to all three forms of wall perturbations is reduced to the same mathematical form: the Rayleigh equation subject to an equivalent suction/blowing velocity, which can be expressed explicitly in terms of the physical wall perturbations. Estimates of the magnitude of the excited eigenmode can be made a priori for each case. Furthermore, the receptivity efficiencies for the streamwise velocity and temperature perturbations are quantitatively related to that for the blowing/suction by simple ratios, which are of $$O(R^{-1/2})$$

O
(

R

-
1
/
2

)

and have simple expressions, where R is the Reynolds number based on the boundary-layer thickness at the centre of the forcing slot. The simple leading-order asymptotic theory predicts the instability and receptivity characteristics accurately for sufficiently large Reynolds numbers (about $$10^4$$

10
4

), but appreciable error exists for moderate Reynolds numbers. An improved asymptotic theory is developed by using the appropriate impedance condition that accounts for the $$O(R^{-1/2})$$

O
(

R

-
1
/
2

)

transverse velocity induced by the viscous motion in the Stokes layer adjacent to the wall. The improved theory predicts both the instability and receptivity at moderate Reynolds numbers ($$R=O(10^3)$$

R
=
O
(

10
3

)

) with satisfactory accuracy. In particular, it captures well the finite-Reynolds-number effects, including the Reynolds-number dependence of the receptivity and the strong excitation occurring near the so-called synchronisation point.
A brief radiological survey and associated occupational exposure to radiation in an open pit slate mine in Kashan, Iran
Authors: Shahrokhi Amin , Adelikhah Mohammademad , Imani Morteza , Kovács Tibor
Published: June 2021

A comprehensive radiological survey was carried out in an open-cut slate stone quarry. The activity of 226Ra, 228Ra and 40 K in the ore samples were measured as 38 ± 5, 41 ± 6 and 869 ± 52 Bq kg1, respectively. Outdoor radon and indoor radon concentrations were measured from 37 ± 7 to 193 ± 11 Bq m−3 (77 ± 8 Bq m−3), and 49 ± 6 to 253 ± 23 Bq m−3 (131 ± 13 Bq m−3), respectively. The average indoor and outdoor gamma dose were measured as 116 and 84 nSv h− 1, respectively. The annual effective doses were estimated between 1.0 ± 0.1 and 3.3 ± 0.3 mSv year−1. The annual lung cancer risks were calculated in the range of 3.3 × 10−2 to 13.12 × 10−2 % (7.72 × 10−2%).
Controlling the Friction of Gels by Regulating Interfacial Oxygen During Polymerization
Authors: Simič Rok , Spencer Nicholas D.
Published: June 2021

Hydrogel surfaces are of great interest in applications ranging from cell scaffolds and transdermal drug-delivery patches to catheter coatings and contact lenses. In this work, we propose a method to control the surface structure of hydrogels, thereby tailoring their frictional properties. The method is based on oxygen inhibition of the free-radical polymerization reaction during synthesis and enables (i) control of friction over more than an order in magnitude and (ii) spatial control of friction as either a continuous gradient or a distinct pattern. The presented method has successfully been applied to acrylamide-, diacrylate- and methacrylate-based gels, illustrating the universality of the presented method, and its potential use in the above-mentioned applications.

Graphical Abstract
Correction to: Experimental research in management accounting
Authors: Knauer Thorsten , Küpper Hans-Ulrich , Schreck Philipp , Sommer Friedrich , Wöhrmann Arnt
Published: June 2021

A correction to this paper has been published: https://doi.org/10.1007/s11573-021-01041-0
SCOPE 2021: a new scorecard for osteoporosis in Europe
Authors: Kanis John A. , Norton Nicholas , Harvey Nicholas C. , Jacobson Trolle , Johansson Helena , Lorentzon Mattias , McCloskey Eugene V. , Willers Carl , Borgström Fredrik
Published: June 2021

Summary

This scorecard summarises key indicators of the burden of osteoporosis and its management in the 27 member states of the European Union, as well as the UK and Switzerland. The resulting scorecard elements, assembled on a single sheet, provide a unique overview of osteoporosis in Europe.

Introduction

The scorecard for osteoporosis in Europe (SCOPE) is a project of the International Osteoporosis Foundation (IOF) that seeks to raise awareness of osteoporosis care in Europe. The aim of this project was to develop a scorecard and background documents to draw attention to gaps and inequalities in the provision of primary and secondary prevention of fractures due to osteoporosis.

Methods

The SCOPE panel reviewed the information available on osteoporosis and the resulting fractures for each of the 27 countries of the European Union plus the UK and Switzerland (termed EU27+2). The information obtained covered four domains: background information (e.g. the burden of osteoporosis and fractures), policy framework, service provision and service uptake, e.g. the proportion of men and women at high risk that do not receive treatment (the treatment gap).

Results

There was a marked difference in fracture risk among the EU27+2 countries. Of concern was the marked heterogeneity in the policy framework, service provision and service uptake for osteoporotic fracture that bore little relation to the fracture burden. For example, despite the wide availability of treatments to prevent fractures, in the majority of the EU27+2, only a minority of patients at high risk receive treatment even after their first fracture. The elements of each domain in each country were scored and coded using a traffic light system (red, orange, green) and used to synthesise a scorecard. The resulting scorecard elements, assembled on a single sheet, provide a unique overview of osteoporosis in Europe.

Conclusions

The scorecard enables healthcare professionals and policy makers to assess their country’s general approach to the disease and provide indicators to inform the future provision of healthcare.
Mini-review: The Role of the Cerebellum in Visuomotor Adaptation
Authors: Tzvi Elinor , Loens Sebastian , Donchin Opher
Published: June 2021

The incredible capability of the brain to quickly alter performance in response to ever-changing environment is rooted in the process of adaptation. The core aspect of adaptation is to fit an existing motor program to altered conditions. Adaptation to a visuomotor rotation or an external force has been well established as tools to study the mechanisms underlying sensorimotor adaptation. In this mini-review, we summarize recent findings from the field of visuomotor adaptation. We focus on the idea that the cerebellum plays a central role in the process of visuomotor adaptation and that interactions with cortical structures, in particular, the premotor cortex and the parietal cortex, may be crucial for this process. To this end, we cover a range of methodologies used in the literature that link cerebellar functions and visuomotor adaptation; behavioral studies in cerebellar lesion patients, neuroimaging and non-invasive stimulation approaches. The mini-review is organized as follows: first, we provide evidence that sensory prediction errors (SPE) in visuomotor adaptation rely on the cerebellum based on behavioral studies in cerebellar patients. Second, we summarize structural and functional imaging studies that provide insight into spatial localization as well as visuomotor adaptation dynamics in the cerebellum. Third, we discuss premotor — cerebellar interactions and how these may underlie visuomotor adaptation. And finally, we provide evidence from transcranial direct current and magnetic stimulation studies that link cerebellar activity, beyond correlational relationships, to visuomotor adaptation .
First record of late Valanginian ammonites from the Mecsek Mountains (Hungary), and their importance for regional stratigraphy
Authors: Bujtor László , Gőgös Gergő
Published: June 2021

A fairly preserved ammonite of Early Cretaceous age from the Mecsek Mountains, southern Hungary is described.Tescheniceras subpachydicranumis the first record of late Valanginian ammonites from the Mecsek tectonic zone from a previously unknown locality indicating the uppermost Valanginian Criosarasinella furcillata Zone. This is the first ammonite-supported evidence for the presence of upper Valanginian strata in the Mecsek Mountains that stretches the time-span of the continuous basinal sedimentation from the beginning of the Berriasian till the Valanginian. The new finding raises the possibility for the presence of the Hauterivian strata too, which was never recognised by ammonites.
Development of Custom Wall-Less Cardiovascular Flow Phantoms with Tissue-Mimicking Gel
Authors: Laughlin Megan E. , Stephens Sam E. , Hestekin Jamie A. , Jensen Morten O.
Published: June 2021

Purpose

Flow phantoms are used in experimental settings to aid in the simulation of blood flow. Custom geometries are available, but current phantom materials present issues with degradability and/or mimicking the mechanical properties of human tissue. In this study, a method of fabricating custom wall-less flow phantoms from a tissue-mimicking gel using 3D printed inserts is developed.

Methods

A 3D blood vessel geometry example of a bifurcated artery model was 3D printed in polyvinyl alcohol, embedded in tissue-mimicking gel, and subsequently dissolved to create a phantom. Uniaxial compression testing was performed to determine the Young’s moduli of the five gel types. Angle-independent, ultrasound-based imaging modalities, Vector Flow Imaging (VFI) and Blood Speckle Imaging (BSI), were utilized for flow visualization of a straight channel phantom.

Results

A wall-less phantom of the bifurcated artery was fabricated with minimal bubbles and continuous flow demonstrated. Additionally, flow was visualized through a straight channel phantom by VFI and BSI. The available gel types are suitable for mimicking a variety of tissue types, including cardiac tissue and blood vessels.

Conclusion

Custom, tissue-mimicking flow phantoms can be fabricated using the developed methodology and have potential for use in a variety of applications, including ultrasound-based imaging methods. This is the first reported use of BSI with an in vitro flow phantom.
The Coupling Effect of Flood Discharge and Storm Surge on Extreme Flood Stages: A Case Study in the Pearl River Delta, South China
Authors: Wang Xianwei , Guo Yu , Ren Jie
Published: June 2021

The low-lying Pearl River Delta in South China is subject to severe flood threats due to watershed floods, sea level rise, and storm surges. It is still unknown to what extent and how far inland storm surges and sea level rise impact the extreme flood stages. This study investigated the coupling effect of flood discharge and storm surge on the extreme flood stages in the Pearl River Delta by using on site observations and simulations generated by the Hydrologic Engineering Center-River Analysis System model. The results show that flood discharges dominated the flood stages in the middle and upper Pearl River Delta, while the storm surges had maximum impact near the river mouth. The storm surges and flood stages showed a significant increase after 2002 in the Hengmen waterway. The design flood stages for the post-2002 period were 0.23–0.89 m higher than the pre-2002 ones at Hengmen at the six return periods from 5 to 200 years examined in this study. Their difference declined toward the upper waterway and reduced to zero about 23 km away from the Hengmen outlet. The coincidence of extreme flood discharges and storm surges further escalates the extreme flood stages in the lower 30 km of estuarine waterways. Our results quantify the severe threats due to sea level rise and intensified storm surges in the lower Pearl River Delta, and are significant for urban planning and designing and managing flood control facilities in the Pearl River Delta and in other coastal fluvial deltas.
Middle English Romance and the Craft of Memory
Authors: McKinstry Jamie
Published: June 2021

In Middle English romances many memories are created, stored, forgotten, and rediscovered by both the characters and audience; such memory work is not, however, either simple or obvious. This study examines the ways in which recollection is achieved and sustained through physical, cognitive, and interpretative challenges. It uses examples such as Sir Gawain and the Green Knight, Sir Orfeo,and Emaré, alongside romances by Chaucer and Malory, to investigate the genre's reliance on individual and collective memorial processes. The author argues that a tale's objects, places, dreams, discoveries, disguises, prophecies, and dramatic ironies influence that romance's essential memory work, which relies as much on creativity as it does accuracy. He also explores the imaginative crafts of memory that are employed by romances themselves. Dr Jamie McKinstry teaches in the Department of English Studies at Durham University, where he is a member of the Institute of Medieval and Early Modern Studies.
The Livery Collar in Late Medieval England and Wales
Authors: Ward Matthew
Published: June 2021

The livery collar had a pervasive presence in late-medieval England. Worn about the neck to denote service to a lord, references to the collar abound in government records, contemporary chronicles andcorrespondence, and many depictions of the collar can be found in illuminated manuscripts and on church monuments. From the fifteenth century the collar was regarded as a powerful symbol of royal power, the artefact associating the recipient with the king; it also played a significant function in the construction and articulation of political and other group identities during the period. This first book-length study of the livery collar examines its cultural and political significance from the late fourteenth to the early sixteenth centuries, in particular between 1450 and 1500, the period associated with the Wars of the Roses. It explores the principal meanings bestowed on the collar, considers the item in its various political contexts, and places the collar within the sphere of medieval identity construction. It also investigates the motives which lay behind its distribution, shedding new light on the nature and understanding of royal power at the time. Matthew Ward teaches medieval history at the University of Nottingham.
Muslim Fula Business Elites and Politics in Sierra Leone
Authors: Jalloh Alusine
Published: June 2021

The first comprehensive book on the participation of Muslim Fula business elites in the post-independence politics of Sierra Leone.
Nikolay Myaskovsky
Authors: Zuk Patrick
Published: June 2021

Drawing on a wealth of unexplored sources, this biography offers the first comprehensive critical reappraisal of the life and works of Nikolay Myaskovsky. Zuk's account is far removed from Cold War clichés of the regimented Sovietartist or sentimental stereotypes of persecuted genius.
Bizet in Italy
Authors: Macdonald Hugh
Published: June 2021

The first English translation of Bizet's letters and journals from his stay in Italy, with explanatory texts from one of the leading authorities on the composer's life and music.
Musical Analyses and Musical Exegesis
Authors: Nattiez Jean-Jacques , Huguet Joan Campbell
Published: June 2021

Here translated for the first time, Jean-Jacques Nattiez's widely hailed comparative guide to the techniques of music analysis focuses on a single vivid passage from Wagner's Tristan and Isolde.
Partisan media effects beyond one-shot experimental designs
Authors: Searles Kathleen , Darr Joshua P. , Sui Mingxiao , Kalmoe Nathan , Pingree Raymond , Watson Brian
Published: June 2021

Previous study demonstrates that partisans perceive in-party news outlets as fair, and out-party news outlets as unfair. However, much of this study relies on one-shot designs. We create an ecologically valid design that randomly assigns participants to news feeds within a week-long online news portal where the balance of in-party and out-party news outlets has been manipulated. We find that sustained exposure to a feed that features out-party news media attenuates Democrats' beliefs that Fox News is unfair, but the same is not true for Republican's perceptions of MSNBC's fairness. Unexpectedly, repeated exposure to in-party news did increase Republicans' beliefs that Fox News is unfair. This study updates our understanding of partisan news effects in a fragmented online news environment.
Top-down causation in psychiatric disorders: a clinical-philosophical inquiry
Authors: Kendler Kenneth S. , Woodward James
Published: June 2021

Psychiatry has long debated whether the causes of mental illness can be better explained by reductionist or pluralistic accounts. Although the former relies on commonsense scientific bottom-up causal models, the latter (which typically include environmental, psychological, and/or socio-cultural risk factors) requires top-down causal processes often viewed with skepticism, especially by neuroscientists. We begin with four clinical vignettes which illustrate self-interventions wherein high-order psychological processes (e.g. religious beliefs or deep interpersonal commitments) appear to causally impact the risk for or the course of psychiatric/behavioral disorders. We then propose a model for how to understand this sort of top-down self-causation. Our model relies centrally on the concept of a control variable which, like a radio tuning dial, can implement a series of typically unknown physical processes to obtain the desired ends. We set this control variable in the context of an interventionist account of causation that assumes that a cause (C) produces an effect (E) when intervening on C (by manipulating it) is associated with a change in E. We extend this framework by arguing that certain psychological changes can result from individuals intervening on their own mental states and/or selection of environments. This in turn requires a conception of the self that contains mental capacities that are at least partially independent of one another. Although human beings cannot directly intervene on the neurobiological systems which instantiate risk for psychiatric illness, they can, via control variables at the psychological level, and/or by self-selection into protective environments, substantially alter their own risk.
Changes in depression and suicidal ideation under severe lockdown restrictions during the first wave of the COVID-19 pandemic in Spain: a longitudinal study in the general population
Authors: Ayuso-Mateos J. L. , Morillo D. , Haro J. M. , Olaya B. , Lara E. , Miret M.
Published: June 2021

Aims

To assess whether there is a change in the prevalence of depression and suicidal ideation after the strict lockdown measures due to the first wave of the COVID-19 pandemic in Spain; and to assess which are the factors associated with the incidence of a depressive episode or suicidal ideation during the lockdown.

Methods

Data from a longitudinal adult population-based cohort from the provinces of Madrid and Barcelona were analysed (n= 1103). Structured face-to-face home-based interviews (pre-pandemic) and telephone interviews were performed. Both depression and suicidal ideation were assessed through an adaptation of the Composite International Diagnostic Interview (CIDI 3.0). A variety of validated instruments and sociodemographic variables including age, sex, educational level, occupational status, home quietness, screen time, resilience, loneliness, social support, physical activity, disability, economic situation and COVID-19-related information were also considered. Population prevalence estimates and multivariable logistic regressions were computed.

Results

Overall, prevalence rates of depression and suicidal ideation did not change significantly from before to after the COVID-19 outbreak. However, the rates of depression among individuals aged 50+ years showed a significant decrease compared to before the pandemic (from 8.48 to 6.41%;p= 0.01). Younger individuals (odds ratio (OR) = 0.97 per year older; 95% confidence interval (CI) = 0.95–0.99) and those feeling loneliness (OR = 1.96; 95% CI = 1.42–2.70) during the lockdown were at an increased risk of developing depression during the confinement. Resilience showed a protective effect against the risk of depression (OR = 0.46; 95% CI = 0.32–0.66) and suicidal ideation (OR = 0.33; 95% CI = 0.16–0.68), whereas individuals perceiving social support were at a lower risk of developing suicidal thoughts (OR = 0.35; 95% CI = 0.18–0.69).

Conclusions

Continuous reinforcement of mental health preventive and intervening measures during and in the aftermath of the crisis is of global importance, particularly among vulnerable groups who are experiencing the most distress. Future research should strive to evaluate the long-term effects of the COVID-19 crisis on mental health.
Transnationalizing Intrapreneurs and Entrepreneurial Values: Case Studies of Chinese Companies in Chiang Mai, Thailand
Authors: Siriphon Aranya , Li Jiangyu
Published: June 2021

This article explores recent waves of Chinese mobility demonstrated by new Chinese emigrants working for private Chinese companies conducting transnational business in Thailand in general and Chiang Mai Province in particular. We use two case studies of international education centres and real estate for senior care businesses in Chiang Mai to discuss the flexibility of Chinese capitalism and argue that deploying intrapreneurs and cultivating entrepreneurial value for employees, professionals and co-partners in pursuit of transnational business are some of the more flexible strategies that China's private companies have employed in response to their new business lines and emerging market demand from both China and other parts of the globe. However, while the Chinese and Thai states have played an important role in facilitating and regulating business conducted in Thailand, transnational business is in an early stage, as demonstrated by the two case studies explored, and may not always proceed as expected.
Tropical Stratospheric Circulation and Ozone Coupled to Pacific Multi‐Decadal Variability
Authors: Iglesias‐Suarez Fernando , Wild Oliver , Kinnison Douglas E. , Garcia Rolando R. , Marsh Daniel R. , Lamarque Jean‐François , Ryan Edmund M. , Davis Sean M. , Eichinger Roland , Saiz‐Lopez Alfonso , Young Paul J.
Published: June 2021

Observational and modeling evidence suggest a recent acceleration of the stratospheric Brewer‐Dobson circulation (BDC), driven by climate change and stratospheric ozone depletion. However, slowly varying natural variability can compromise our ability to detect such forced changes over the relatively short observational record. Using observations and chemistry‐climate model simulations, we demonstrate a link between multi‐decadal variability in the strength of the BDC and the Interdecadal Pacific Oscillation (IPO), with knock‐on impacts for composition in the stratosphere. After accounting for the IPO‐like variability in the BDC, the modeled trend is approximately 7%–10% dec−1 over 1979–2010. Furthermore, we find that sea surface temperatures explain up to 50% of the simulated decadal variability in tropical mid‐stratospheric ozone. Our findings demonstrate strong links between low‐frequency variability in the oceans, troposphere and stratosphere, as well as their potential importance in detecting structural changes in the BDC and future ozone recovery.
Observations of SST‐Induced Wind Perturbations in the Leeuwin Current
Authors: Wang Sen , Feng Ming , Dong Changming , Zhu Weijun
Published: June 2021

Sea surface temperature (SST) perturbations modify low‐level winds through the influence of air‐sea heat flux across the marine atmospheric boundary layer, mostly observable in the major western boundary current systems. In this study, we investigate the effects of SST on surface winds in a poleward‐flowing eastern boundary current system, the Leeuwin Current (LC), using the Advanced Very High‐Resolution Radiometer (AVHRR) SST and wind data from Cross‐Calibrated Multi‐Platform (CCMP) during 2009–2018. There exist robust linear relationships between perturbation SST and perturbation wind speed and their derivatives in the LC. The regression slopes between SST perturbations and wind perturbations appear to be higher in austral summer when the alongshore northward winds are strongly opposing the LC, however, the relationships in winter are statistically more robust when the LC and associated cross‐shore SST fronts are the strongest. Consistent with previous studies in the western boundary currents, crosswind perturbation wind speed gradient is the largest for the winds 80° (−100°) to the right (left) of the SST gradient in the LC region. The perturbation wind stress curl induced by the SST signature of the LC causes positive wind stress curl anomalies on the offshore edge of the LC, driving anomalous downwelling and would reduce surface chlorophyll a concentrations along the LC SST front as observed in satellite data, which may have implications in regional biogeochemistry.
The Dynamics of Diachronous Extinction Associated With Climatic Deterioration Near the Neogene/Quaternary Boundary
Authors: Brombacher Anieke , Wilson Paul A. , Bailey Ian , Ezard Thomas H. G.
Published: June 2021

To predict extinction, we must understand the processes leading to terminal population decline. Once a critical threshold of population size is reached, small environmental perturbations can push a species over the cliff‐edge to extinction, so the main drivers of extinction are the factors that cause the initial reduction in population size. Most studies of population decline leading up to extinction focus on modern species in a human‐dominated world. The drivers of population decline leading to non‐human mediated extinctions are less well known but changes in climate are arguably the most widely invoked mechanism. Here, we report data on >16,000 individuals of the planktonic foraminifer Globoconella puncticulata from six sites in the Atlantic Ocean along an 83 degree‐long latitudinal transect, over a 600,000‐years interval leading up to the species’ global extinction during the late Pliocene‐earliest Pleistocene intensification of Northern Hemisphere glaciation. We show changes in geographic range, abundance, and body size. We find that populations do not follow a North‐to‐South sequence in extinction as Earth cooled and developed large ice sheets in the high latitudes of the Northern Hemisphere. Instead, our results suggest that (a) populations are differentially adapted to local environmental conditions such as nutrient availability, (b) population dynamics in core populations differ from those at the edge of their range, and (c) individual population responses to external pressures are essential to understanding the drivers of global extinction. Our study demonstrates the potential to transform our understanding of extinction dynamics through spatially replicated sampling of the highly resolved marine microfossil record.
Investigating Magma Ocean Solidification on Earth Through Laser‐Heated Diamond Anvil Cell Experiments
Authors: Nabiei Farhang , Badro James , Boukaré Charles‐Édouard , Hébert Cécile , Cantoni Marco , Borensztajn Stephan , Wehr Nicolas , Gillet Philippe
Published: June 2021

We carried out a series of silicate fractional crystallization experiments at lower mantle pressures using the laser‐heated diamond anvil cell. Phase relations and the compositional evolution of the cotectic melt and equilibrium solids along the liquid line of descent were determined and used to assemble the melting phase diagram. In a pyrolitic magma ocean, the first mineral to crystallize in the deep mantle is iron‐depleted calcium‐bearing bridgmanite. From the phase diagram, we estimate that the initial 33%–36% of the magma ocean will crystallize to form such a buoyant bridgmanite. Substantial calcium solubility in bridgmanite is observed up to 129 GPa, and significantly delays the crystallization of the calcium silicate perovskite phase during magma ocean solidification. Residual melts are strongly iron‐enriched as crystallization proceeds, making them denser than any of the coexisting solids at deep mantle conditions, thus supporting the terrestrial basal magma ocean hypothesis (Labrosse et al., 2007).
Frictional Origin of Slip Events of the Whillans Ice Stream, Antarctica
Authors: Guerin Gauthier , Mordret Aurélien , Rivet Diane , Lipovsky Bradley P. , Minchew Brent M.
Published: June 2021

Ice sheet evolution depends on subglacial conditions, with the ice‐bed interface's strength exerting an outsized role on the ice dynamics. Along fast‐flowing glaciers, this strength is often controlled by the deformation of subglacial till, making quantification of spatial variations of till strength essential for understanding ice‐sheet contribution to sea‐level. This task remains challenging due to a lack of in situ observations. We analyze continuous seismic data from the Whillans Ice Plain (WIP), West Antarctica, to uncover spatio‐temporal patterns in subglacial conditions. We exploit tidally modulated stick‐slip events as a natural source of sliding variability. We observe a significant reduction of the till seismic wave‐speed between the WIP sticky‐spots. These observations are consistent with a poroelastic model where the bed experiences relative porosity and effective pressure increases of >11% during stick‐slips. We conclude that dilatant strengthening appears to be an essential mechanism in stabilizing the rapid motion of fast‐flowing ice streams.
Devils Hole Calcite Was Precipitated at ±1°C Stable Aquifer Temperatures During the Last Half Million Years
Authors: Bajnai David , Coplen Tyler B. , Methner Katharina , Löffler Niklas , Krsnik Emilija , Fiebig Jens
Published: June 2021

Subaqueous carbonates from the Devils Hole caves (southwestern USA) provide a continuous Holocene to Pleistocene North American paleoclimate record. The accuracy of this record relies on two assumptions: That carbonates precipitated close to isotope equilibrium and that groundwater temperature did not change significantly in the last 570 thousand years. Here, we investigate these assumptions using dual clumped isotope thermometry. This method relies on simultaneous analyses of carbonate ∆47 and ∆48 values and provides information on the existence and extent of kinetic isotope fractionation. Our results confirm the hypothesis that calcite precipitation occurred close to oxygen and clumped isotope equilibrium during the last half million years in Devils Hole. In addition, we provide evidence that aquifer temperatures varied by less than ±1°C during this interval. Thus, the Devils Hole calcite δ18O time series exclusively represents changes in groundwater δ18O values.
Injection Parameters That Promote Branching of Hydraulic Cracks
Authors: Li Wenfeng , Frash Luke P. , Carey J. William , Welch Nathan J. , Meng Meng , Nguyen Hoang , Viswanathan Hari S. , Rougier Esteban , Lei Zhou , Rahimi‐Aghdam Saeed , Bažant Zdenek P.
Published: June 2021

Fluid injection into rock formations can either produce complex branched hydraulic fractures, create simple planar fractures, or be dominated by porous diffusion. Currently, the optimum injection parameters to create branched fractures are unknown. We conducted repeatable hydraulic fracturing experiments using analog‐rock samples with controlled heterogeneity to quantify the fluid parameters that promote fracture branching. A large range of injection rates and fluid viscosities were used to investigate their effects on induced fracture patterns. Paired with a simple analytical model, our results identify the threshold at which fracture transitions from an isolated planar crack to branched cracks when closed natural fractures exist. These results demonstrate that this transition can be controlled by injection rate and fluid viscosity. In relation to the field practices, the present model predicts slickwater and lower viscosity fluid injections promote fracture branching, with the Marcellus shale used as an example.
Wormholing in Anisotropic Media: Pore‐Scale Effect on Large‐Scale Patterns
Authors: Roded R. , Szymczak P. , Holtzman R.
Published: June 2021

The formation of dissolution conduits by focused reactive flow (i.e., wormholing) in anisotropic media is studied using a pore network model. Simulations reveal a significant effect of anisotropy on wormholing dynamics and medium permeability evolution. Particularly, anisotropy controls wormhole competition and their characteristic spacing. It also affects the flow through the individual wormholes and their shapes, and consequently, shifts the optimum injection rate at which breakthrough is achieved at a minimal expense of reactant. For anisotropic media with low transverse pore conductivities, wormhole distribution ceases to be scale‐invariant and pronounced side‐branches develop. Wormholing is further compared to viscous fingering in an anisotropic network, and other unstable growth processes of similar underlying dynamics. Despite several similarities, few important differences are identified. Our findings contribute to the understanding of wormholing in geological media and demonstrate how pore‐scale features can fundamentally affect the emergence of large‐scale morphologies.
Mid‐Latitude Thermosphere‐Ionosphere Na (TINa) Layers Observed With High‐Sensitivity Na Doppler Lidar Over Boulder (40.13°N, 105.24°W)
Authors: Chu Xinzhao , Chen Yingfei , Cullens Chihoko Y. , Yu Zhibin , Xu Zhonghua , Zhang Shun‐Rong , Huang Wentao , Jandreau Jackson , Immel Thomas J. , Richmond Arthur D.
Published: June 2021

We report the first lidar observations of regular occurrence of mid‐latitude thermosphere‐ionosphere Na (TINa) layers over Boulder (40.13°N, 105.24°W), Colorado. Detection of tenuous Na layers (∼0.1–1 cm−3 from 150 to 130 km) was enabled by high‐sensitivity Na Doppler lidar. TINa layers occur regularly in various months and years, descending from ∼125 km after dusk and from ∼150 km before dawn. The downward‐progression phase speeds are ∼3 m/s above 120 km and ∼1 m/s below 115 km, consistent with semidiurnal tidal phase speeds. One or more layers sometimes occur across local midnight. Elevated volume mixing ratios above the turning point (∼105–110 km) of Na density slope suggest in situ production of the dawn/dusk layers via neutralization of converged Na+ layers. Vertical drift velocity of TINa+ calculated with the Ionospheric Connection Explorer Hough Mode Extension tidal winds shows convergent ion flow phases aligned well with TINa, supporting this formation hypothesis.
Human Influence on the Increasing Drought Risk Over Southeast Asian Monsoon Region
Authors: Zhang Lixia , Chen Ziming , Zhou Tianjun
Published: June 2021

Southeast Asian monsoon region is regularly stricken by drought, but less attention is paid due to its slow‐onset and less visual impact. This study investigated the observed drought changes over Southeast Asian monsoon region and impacts of anthropogenic forcing using the Coupled Model Intercomparison Project Phase 6 models. We revealed an increasing drought risk for 1951–2018 due to more frequent and wide‐spread droughts. The influence of anthropogenic forcing is successfully detected, which has increased the likelihood of the extreme droughts in historical simulation by reducing precipitation and enhancing evapotranspiration. The time of emergence of anthropogenic forcing in extreme drought occurrence and affected area occurs around the 1960s. The future projected severe and extreme drought risks are still beyond natural only forced changes under all scenarios. Our findings demonstrate a robust impact of anthropogenic forcing on drought risk over Southeast Asia, and highlight the importance of future pathway choice.
Nuclear scaffold protein p54nrb/NONO facilitates the hypoxia-enhanced progression of hepatocellular carcinoma
Authors: Shen Mengqin , Zhang Ruixue , Jia Wenzhi , Zhu Zongping , Zhao Xiaoping , Zhao Li , Huang Gang , Liu Jianjun
Published: June 2021

Hypoxia and related oxidative stress are closely related to the development and treatment of hepatocellular carcinoma (HCC). However, the mechanism mediated by hypoxia in HCC has not yet been elucidated. Here, we found multifunction scaffold protein p54nrb/NONO exerted pleiotropic effects to regulate hypoxia transcription signals, thereby enhancing the progression of liver cancer. Extensive analysis of clinical data demonstrated that NONO was significantly upregulated and represented as a poor prognostic indicator of HCC. The crucial role of NONO in driving angiogenesis and glycolysis, two well-known cancer phenotypes mediated by hypoxia, was examined in vitro an in vivo. Mechanistically, NONO interacted with and stabilized both HIF-1 and HIF-2 complexes thus activating the transcription of hypoxia-induced genes. Besides, NONO bound pre-mRNA and subsequent mRNA of these genes to facilitate them splicing and mRNA stability, respectively. Thus, NONO knockout seriously disrupted the expression of a cluster of HIF-1/2 targets and impeded hypoxia-enhanced progression in HCC. In conclusion, NONO functioned as a multipurpose scaffold that interacted with HIF-1/2 complex and their downstream transcripts to facilitate the expression of hypoxia-induced genes, allowing malignant proliferation, indicating that NONO might be a potential therapeutic target for HCC.
Comparison of two Borg exertion scales for monitoring exercise intensity in able-bodied participants, and those with paraplegia and tetraplegia
Authors: Hutchinson Michael J. , Kouwijzer Ingrid , de Groot Sonja , Goosey-Tolfrey Victoria L.
Published: June 2021

Study design

Cross-sectional cohort study.

Objectives

To compare ratings of perceived exertion (RPE) on Borg’s 6–20 RPE scale and Category Ratio 10 (CR10) in able-bodied (AB) participants during upper and lower body exercise, and recreationally active participants with paraplegia (PARA) and athletes with tetraplegia (TETRA) during upper body exercise only.

Setting

University and rehabilitation centre-based laboratories in UK and Netherlands.

Methods

Twenty-four participants were equally split between AB, PARA, and TETRA. AB performed maximal tests using cycle (AB-CYC) and handcycle (AB-HC) ergometry. PARA and TETRA performed maximal handcycle and wheelchair propulsion tests, respectively. Oxygen uptake (V̇O2) and blood lactate concentration were monitored throughout. RPE was rated each stage on Borg’s RPE scale and CR10. Thresholds were identified according to log-V̇O2 plotted against log-blood lactate (LT1), and 1.5 mmol L−1 greater than LT1 (LT2).

Results

RPE from both scales were best fit against each other using a quadratic model, with high goodness of fit between scales that was independent of exercise mode and participant group (range R2: 0.965–0.970, P < 0.005). Though percentage peak V̇O2 was significantly greater in TETRA (P < 0.005), there was no difference in RPE at LT1 or LT2 between groups on Borg’s RPE scale or CR10.

Conclusion

Strong association between Borg’s RPE scale and CR10 suggests they can be used interchangeably. RPE at lactate thresholds were independent of mode of exercise and level of spinal cord injury. However, inter-individual variation precludes from making firm recommendations about using RPE for prescribing homogenous exercise intensity.
Short lifespan of syngeneic transplanted MSC is a consequence of in vivo apoptosis and immune cell recruitment in mice
Authors: Preda Mihai Bogdan , Neculachi Carmen Alexandra , Fenyo Ioana Madalina , Vacaru Ana-Maria , Publik Mihai Alin , Simionescu Maya , Burlacu Alexandrina
Published: June 2021

Mesenchymal stromal cells (MSC) are attractive tools for cell-based therapy, yet the mechanisms underlying their migration and survival post-transplantation are unclear. Accumulating evidence indicates that MSC apoptosis modulates both innate and adaptive immune responses which impact on MSC therapeutic effects. Using a dual tracking system, namely the Luciferase expression and VivoTrack680 labelling, and in vivo optical imaging, we investigated the survival and migration of MSC transplanted by various routes (intravenous, subcutaneous, intrapancreatic and intrasplenic) in order to identify the best delivery approach that provides an accumulation of therapeutic cells to the injured pancreas in the non-obese diabetic (NOD) mouse. The results showed that transplanted MSC had limited migration capacity, irrespective of the administration route, and were short-lived with almost total disappearance at 7 days after transplantation. Within one day after transplantation, cells activated hypoxia signalling pathways, followed by Caspase 3-mediated apoptosis. These were subsequently followed by local recruitment of immune cells at the transplantation site, and the engulfment of apoptotic MSC by macrophages. Our results argue for a “hit and die” mechanism of transplanted MSC. Further investigations will elucidate the molecular crosstalk between the inoculated and the host-immune cells.
Author Correction: Dissecting the cell to nucleus, perinucleus and cytosol
Authors: Shaiken Tattym E. , Opekun Antone R.
Published: June 2021

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Safety and efficacy of laparoscopic repeat liver resection and re-operation for liver tumor
Authors: Takase Koki , Sakamoto Takuya , Takeda Yutaka , Ohmura Yoshiaki , Katsura Yoshiteru , Shinke Go , Kawai Kenji , Murakami Kohei , Kagawa Yoshinori , Masuzawa Toru , Takeno Atsushi , Hata Taishi , Murata Kohei
Published: June 2021

Laparoscopic liver resection (LLR) has been reported as a safe, minimally invasive, and effective surgery for the management of liver tumor. However, the efficacy and safety of laparoscopic repeat liver resection (LRLR) for recurrent liver tumor are unclear. Here, we analyzed the surgical results of LRLR. From June 2010 to May 2019, we performed 575 LLR surgeries in our department, and 454 of them underwent pure LLR for the single tumor. We classified the patients who received pure LLR for the single tumor into three groups: LRLR (n = 80), laparoscopic re-operation after previous abdominal surgery (LReOp; n = 136), and laparoscopic primary liver resection (LPLR; n = 238). We compared patient characteristics and surgical results between patients undergoing LRLR, LReOp and LPLR. We found no significant differences between LRLR and LPLR in the conversion rate to laparotomy (p = 0.8033), intraoperative bleeding (63.0 vs. 152.4 ml; p = 0.0911), or postoperative bile leakage rate (2.50 vs. 3.78%; p = 0.7367). We also found no significant difference in the surgical results between LReOp and LPLR. However, the number of patients undergoing the Pringle maneuver was lower in the LRLR group than the LPLR group (61.3 vs. 81.5%; p = 0.0004). This finding was more pronounced after open liver resection than laparoscopic liver resection (38.9 vs. 67.7%; p = 0.0270). The operative time was significantly longer in patients with proximity to previous cut surface than patients with no proximity to previous cut surface (307.4 vs. 235.7 min; p = 0.0201). LRLR can safely be performed with useful surgical results compared to LPLR.