bluuebunny/crossref_metadata_2025 huggingface dataset:
Development and validation of a delirium risk assessment tool in older patients admitted to the Emergency Department Observation Unit
Authors: Zucchelli A. , Apuzzo R. , Paolillo C. , Prestipino V. , De Bianchi S. , Romanelli G. , Padovani A. , Marengoni A. , Bellelli G.
Published: February 2021

Background

Delirium is frequent though undetected in older patients admitted to the Emergency Department (ED).

Aims

To develop and validate a delirium risk assessment tool for older persons admitted to the ED Observation Unit (OU).

Methods

We used data from two samples of 65 + year-old patients, one admitted to the ED of Brescia Hospital (n = 257) and one to the ED of Desio Hospital (n = 107), Italy. Data from Brescia were used as training sample, those collected in Desio as testing one. Delirium was assessed using the 4AT and patients’ characteristic were retrieved from medical charts. Variables found to be associated with delirium in the training sample were tested for the creation of a delirium risk assessment tool. The resulting tool’s performances were assessed in the testing subsample.

Results

Of all possible scores tested, the combination with the highest discriminative ability in the training sample included: age ≥ 75 years, dementia diagnosis, chronic use of neuroleptics, and hearing impairment. The delirium score exhibited an AUC of 0.874 and 0.893 in the training and testing samples, respectively. For a 1-point increase in the score, the odds of delirium increased more than twice in both samples.

Discussion

We propose a delirium risk assessing tool that includes variables that can be easily collected at ED admission and that can be calculated rapidly.

Conclusion

A risk assessment tool could help improving delirium detection in older persons referring to ED.
Tamped Richtmyer–Meshkov Instability Experiments to Probe High-Pressure Material Strength
Authors: Vogler T. J. , Hudspeth M. C.
Published: February 2021

Dynamic interface instabilities such as Rayleigh–Taylor, Kelvin–Helmholtz, and Richtmyer–Meshkov are important in a number of physical phenomena. Besides meriting study because of their role in natural events and man-made applications, they can also be used to study constitutive properties of materials in extreme conditions. Both RTI and RMI configurations have been used to study the strength of solids at high strain rates, though RMI has largely been limited to zero or ambient pressure. Recently, advances in imaging have allowed tamped RMI experiments to be performed in which the pressure is maintained above ambient. In this study, we examine the tamped RMI for determining material strength. Through simulation, we explore the behavior of the jetting material and examine the sensitivity of jetting to material properties. We identify simple scaling laws that relate the key physical parameters controlling jetting, which are compared to previous results from the literature. We use these scaling law and other considerations to examine issues associated with tamped RMI experiments.
Modulation spaces as a smooth structure in noncommutative geometry
Authors: Austad Are , Luef Franz
Published: February 2021

We demonstrate how to construct spectral triples for twisted group$$C^*$$C∗-algebras of lattices in phase space of a second-countable locally compact abelian group using a class of weights appearing in time–frequency analysis. This yields a way of constructing quantum$$C^k$$Ck-structures on Heisenberg modules, and we show how to obtain such structures using Gabor analysis and certain weighted analogues of Feichtinger’s algebra. We treat the standard spectral triple for noncommutative 2-tori as a special case, and as another example we define a spectral triple on noncommutative solenoids and a quantum$$C^k$$Ck-structure on the associated Heisenberg modules.
Vector mesons in medium
Authors: Lee Su Houng
Published: February 2021

After decades-long attempts to measure the mass shift and understand the origin of hadron mass, it became clear that one has to analyze hadrons with small vacuum width. Also, to identify the effect of chiral symmetry breaking, one has to start by looking at chiral partners. Such considerations inevitably points to studying K∗ and K1 in matter. The masses of both particles can potentially be measured from nuclear target based experiments and/or heavy ion collisions. Once the masses and mass difference of K∗ and K1 mesons are measured, we will be closer to understanding the origin of hadron mass and the effects of chiral symmetry breaking. We will review the topic using the operator product expansion (OPE) perspective.
All the Sonnets of Shakespeare
Authors: Shakespeare William
Published: February 2021

How can we look afresh at Shakespeare as a writer of sonnets? What new light might they shed on his career, personality, and sexuality? Shakespeare wrote sonnets for at least thirty years, not only for himself, for professional reasons, and for those he loved, but also in his plays, as prologues, as epilogues, and as part of their poetic texture. This ground-breaking book assembles all of Shakespeare's sonnets in their probable order of composition. An inspiring introduction debunks long-established biographical myths about Shakespeare's sonnets and proposes new insights about how and why he wrote them. Explanatory notes and modern English paraphrases of every poem and dramatic extract illuminate the meaning of these sometimes challenging but always deeply rewarding witnesses to Shakespeare's inner life and professional expertise. Beautifully printed and elegantly presented, this volume will be treasured by students, scholars, and every Shakespeare enthusiast.
Incidence and Costs of Personal and Property Crimes in the USA, 2017
Authors: Miller Ted R. , Cohen Mark A. , Swedler David I. , Ali Bina , Hendrie Delia V.
Published: February 2021

Total cost estimates for crime in the USA are both out-of-date and incomplete. We estimated incidence and costs of personal crimes (both violent and non-violent) and property crimes in 2017. Incidence came from national arrest data, multi-state estimates of police-reported crimes per arrest, national victimization and road crash surveys, and police underreporting studies. We updated and expanded upon published unit costs. Estimated crime costs totaled $2.6 trillion ($620 billion in monetary costs plus quality of life losses valued at $1.95 trillion; 95 % uncertainty interval $2.2–$3.0 trillion). Violent crime accounted for 85 % of costs. Principal contributors to the 10.9 million quality-adjusted life years lost were sexual violence, physical assault/robbery, and child maltreatment. Monetary expenditures caused by criminal victimization represent 3 % of Gross Domestic Product – equivalent to the amount spent on national defense. These estimates exclude the additional costs of preventing and avoiding crime such as enhanced lighting and burglar alarms. They also exclude crimes against businesses and most white-collar and corporate offenses.
Training Package for Emergency Medical Teams Deployed to Disaster Stricken Areas: Has ‘TEAMS’ Achieved its Goals?
Authors: Bodas Moran , Peleg Kobi , Adini Bruria , Ragazzoni Luca
Published: February 2021

In spite of their good intentions, Emergency Medical Teams (EMTs) were relatively disorganized for many years. To enhance the efficient provision of EMT’s field team work, the Training for Emergency Medical Teams and European Medical Corps (TEAMS) project was established. The purpose of this study was to assess the effectiveness and quality of the TEAMS training package in 2 pilot training programs in Germany and Turkey. A total of 19 German and 29 Turkish participants completed the TEAMS training package. Participants were asked to complete a set of questionnaires designed to assess self-efficacy, team work, and quality of training. The results suggest an improvement for both teams’ self-efficacy and team work. The self-efficacy scale improved from 3.912 (± 0.655 SD) prior to training to 4.580 (± 0.369 SD) after training (out of 5). Team work improved from 3.085 (± 0.591 SD) to 3.556 (± 0.339 SD) (out of 4). The overall mean score of the quality of the training scale was 4.443 (± 0.671 SD) (out of 5). In conclusion, The TEAMS Training Package for Emergency Medical Teams has been demonstrated to be effective in promoting EMT team work capacities, and it is considered by its users to be a useful and appropriate tool for addressing their perceived needs.
Up conversion and excited state absorption analysis in the Tm:YAG disk laser multi-pass pumped by 1 μm laser
Authors: Song Enmao , Zhu Guangzhi , Wang Hailin , Chen Hantian , Qian Yefeng , Aleksei Kozlov , Zhu Xiao
Published: February 2021

We present a 2 μm Tm:YAG disk laser multi-pass pumped by a 1 μm laser. The transitions in competition of up conversion (UC) and excited state absorption (ESA) are analyzed in detail based on a numerical model that considers stimulated emission, fluorescence, non-radiative decay, UC, andESA, showing good agreement with experiments. The proportions and fractional thermal loads of all transitions are derived quantitatively. The results show that UC and ESA are critical in Tm:YAG disk lasers, resulting in a decrease in the absorbed pump power and temperature after lasing for two different disk thicknesses. In addition, although the absorbed pump power of the 0.5 mm disk is lower than in the 1 mm case, its relatively weak UC and ESA and low total fractional thermal load can improve laser performance. A 0.5 mm Tm:YAG disk laser thus delivered the maximum output power of1.05 W with beam quality of Mx2 = 2.02 and My2 = 2.03.
The cyclicity of the period annulus of a reversible quadratic system
Authors: Liu Changjian , Li Chengzhi , Llibre Jaume
Published: February 2021

We prove that perturbing the periodic annulus of the reversible quadratic polynomial differential system $\dot x=y+ax^2$, $\dot y=-x$ with a ≠ 0 inside the class of all quadratic polynomial differential systems we can obtain at most two limit cycles, including their multiplicities. Since the first integral of the unperturbed system contains an exponential function, the traditional methods cannot be applied, except in Figuerasa, Tucker and Villadelprat (2013, J. Diff. Equ., 254, 3647–3663) a computer-assisted method was used. In this paper, we provide a method for studying the problem. This is also the first purely mathematical proof of the conjecture formulated by Dumortier and Roussarie (2009, Discrete Contin. Dyn. Syst., 2, 723–781) for q ⩽ 2. The method may be used in other problems.
Living Together, Voting Together: Voters Moving in Together Before an Election Have Higher Turnout
Authors: Dahlgaard Jens Olav , Bhatti Yosef , Hansen Jonas Hedegaard , Hansen Kasper M.
Published: February 2021

Scholars have long noted that couples are more likely to vote compared to individuals who live alone, and that partners' turnout behavior is strongly correlated. This study examines a large administrative dataset containing detailed information about validated turnout and the timing of individuals moving in together, and finds evidence of a substantial and robust increase in turnout after cohabitation. The study exploits the fact that two-voter households moving in together right before an election are comparable to those moving in together right after the election. Depending on the model specification, turnout increases by 3.5 to 10.6 percentage points in the months after taking up cohabitation. Voters are mobilized regardless of their own and their cohabitant's turnout behavior in a previous election. The results are robust to several robustness checks, including benchmarking with singles who move to mitigate the cost of moving in the analysis. The results highlight the importance of social norms and the household's essential role as a proximate social network that increases turnout.
Petrological and geochemical characterization of the arc-related Suru–Thasgam ophiolitic slice along the Indus Suture Zone, Ladakh Himalaya
Authors: Bhat I.M. , Ahmad T. , Rao D.V. Subba , Rao N.V. Chalapathi
Published: February 2021

The Ladakh Himalayan ophiolites preserve remnants of the eastern part of the Neo-Tethyan Ocean, in the form of Dras, Suru Valley, Shergol, Spongtang and Nidar ophiolitic sequences. In Kohistan region of Pakistan, Muslim Bagh, Zhob and Bela ophiolites are considered to be equivalents of Ladakh ophiolites. In western Ladakh, the Suru–Thasgam ophiolitic slice is highly dismembered and consists of peridotites, pyroxenites and gabbros, emplaced as imbricate blocks thrust over the Mesozoic Dras arc complex along the Indus Suture Zone. The Thasgam peridotites are partially serpentinized with relict olivine, orthopyroxene and minor clinopyroxene, as well as serpentine and iron oxide as secondary mineral assemblage. The pyroxenites are dominated by clinopyroxene followed by orthopyroxene with subordinate olivine and spinel. Gabbros are composed of plagioclase and pyroxene (mostly replaced by amphiboles), describing an ophitic to sub-ophitic textural relationship. Geochemically, the studied rock types show sub-alkaline tholeiitic characteristics. The peridotites display nearly flat chondrite-normalized rare earth element (REE) patterns ((La/Yb)N = 0.6–1.5), while fractionated patterns were observed for pyroxenites and gabbros. Multi-element spidergrams for peridotites, pyroxenites and gabbros display subduction-related geochemical characteristics such as enriched large-ion lithophile element (LILE) and depleted high-field-strength element (HFSE) concentrations. In peridotites and pyroxenites, highly magnesian olivine (Fo88.5-89.3 and Fo87.8-89.9, respectively) and clinopyroxene (Mg no. of 93–98 and 90–97, respectively) indicate supra-subduction zone (SSZ) tectonic affinity. Our study suggests that the peridotites epitomize the refractory nature of their protoliths and were later evolved in a subduction environment. Pyroxenites and gabbros appear to be related to the base of the modern intra-oceanic island-arc tholeiitic sequence.
A historical review of the evolution of nasal lavage systems
Authors: Fandino A , Douglas R
Published: February 2021

Background

Nasal lavage is an ancient practice that still has a fundamental role in the management of sinonasal conditions. The history related to these devices is extensive and remarkable. By reviewing it, it is hoped that a broader view can be achieved on what is currently possible with nasal lavage and how advances may be made in the future.

Methods

A careful review of different sources, such as ancient manuscripts, registered patents and scientific papers, was conducted to achieve a thorough examination of the history related to nasal rinsing devices.

Conclusion

Nasal lavage has evolved significantly since first considered for medical use and has always played a central role in the treatment of patients with sinonasal conditions. Further innovation is still necessary to surmount the shortcomings of current nasal lavage systems.
Variation in size distribution of juvenile pink shrimps Farfantepenaeus brasiliensis and F. paulensis in the estuarine-adjacent ocean area of Cananéia, south-eastern coast of Brazil
Authors: Salvati Dalilla da Silva , Perroca Júlia Fernandes , Simões Sabrina Morilhas , Castilho Antonio Leão , Costa Rogerio Caetano da
Published: February 2021

The study characterized the structure of juveniles and sub-adults of Farfantepenaeus brasiliensis and F. paulensis in the Cananéia-Iguape estuarine lagoon system and its adjacent coastal area by evaluating the period of juvenile recruitment, sex ratio, growth, longevity, natural mortality, and development time until the late juvenile phase. Samples were collected from July 2012 to June 2014. Shrimps were identified by species and sex, and measured (carapace length – CL mm); 889 individuals of F. brasiliensis and 848 of F. paulensis were analysed. Females were more abundant than males for both species. The growth parameters of F. brasiliensis were: CL∞ = 45.5 mm, k = 1.8 year−1 for males and CL∞ = 55.2 mm, k = 1.6 year−1 for females; longevity of 2.52 years (males) and 2.88 years (females); and natural mortality of 1.71 (males) and 1.55 (females). For F. paulensis, the following values were observed: CL∞ = 40.7 mm, k = 2.3 year−1 for males and CL∞ = 56.5 mm, k = 1.9 year−1 for females; longevity of 2.04 years (males) and 2.37 years (females); and natural mortality of 2.39 (males) and 2.05 (females). The juvenile recruitment of both species peaked in January 2014. The development time until late juvenile phase was ~7 months (F. brasiliensis) and ~5 months (F. paulensis). Even though the highest abundance of juveniles did not occur in the closed season, fishing is forbidden in the estuarine area and the migration towards the adult population occurred close to or even during the closed season.
Symptoms and laboratory manifestations of mild COVID-19 in a repatriated cruise ship cohort
Authors: Bailie C. R. , Franklin L. , Nicholson S. , Mordant F. , Alpren C. , Stewart T. , Barnes C. , Fox A. , Druce J. , Subbarao K. , Catton M. , van Diemen A. , Sullivan S. G.
Published: February 2021

Much of our current understanding about novel coronavirus disease 2019 (COVID-19) comes from hospitalised patients. However, the spectrum of mild and subclinical disease has implications for population-level screening and control. Forty-nine participants were recruited from a group of 99 adults repatriated from a cruise ship with a high incidence of COVID-19. Respiratory and rectal swabs were tested by polymerase chain reaction (PCR) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Sera were tested for anti-SARS-CoV-2 antibodies by enzyme-linked immunosorbent assay (ELISA) and microneutralisation assay. Symptoms, viral shedding and antibody response were examined. Forty-five participants (92%) were considered cases based on either positive PCR or positive ELISA for immunoglobulin G. Forty-two percent of cases were asymptomatic. Only 15% of symptomatic cases reported fever. Serial respiratory and rectal swabs were positive for 10% and 5% of participants respectively about 3 weeks after median symptom onset. Cycle threshold values were high (range 31–45). Attempts to isolate live virus were unsuccessful. The presence of symptoms was not associated with demographics, comorbidities or antibody response. In closed settings, incidence of COVID-19 could be almost double that suggested by symptom-based screening. Serology may be useful in diagnosis of mild disease and in aiding public health investigations.
Coronary compression testing by balloon interrogation during pulmonary valve implantation: room for doubt?
Authors: Morgan Gareth J. , Rodriguez Salvador A. , Leahy Ryan , Zablah Jenny E.
Published: February 2021

Objective:

To evaluate the reliability of balloon coronary compression testing during percutaneous pulmonary valve implantation.

Background:

Despite the widespread use of the ‘balloon coronary test’ as the preferable method to rule out the risk of coronary compression, this adverse event has been described after pulmonary valve implantation where coronary balloon test suggested no risk or low risk, calling into question the accuracy of the test.

Methods:

We performed a retrospective chart review of 84 patients who underwent pulmonary valve implantation between January 2018 and December 2019 and selected 36 patients whose archived imaging was suitable to perform quantitative analysis of the ‘balloon coronary test’. We focused on the spatial disparity between the right ventricular outflow tract position defined by the inflated testing balloon and the eventual implanted valve position, to classify the test as inaccurate or accurate.

Results:

In total, 36.1% of cases were classified as having an inaccurate coronary balloon test. Among the baseline characteristics, right ventricular outflow tract substrate was identified as a significant predictor of test accuracy. Related to this characteristic, the type of testing balloon used and the size of the eventually implanted valve were found to be associated with test accuracy.

Conclusions:

Based on our findings, balloon coronary testing is not an accurate method of predicting final valve position with respect to fixed structures in the thorax. This may translate to a high false positive rate for the likelihood of coronary compression in pulmonary valve implantation.
Disparate Associations of Years of Football Participation and a Metric of Head Impact Exposure with Neurobehavioral Outcomes in Former Collegiate Football Players
Authors: Brett Benjamin L. , Nader Amy M. , Kerr Zachary Y. , Chandran Avinash , Walton Samuel R. , DeFreese J. D. , Guskiewicz Kevin M. , McCrea Michael
Published: February 2021

Objectives:

Years of sport participation (YoP) is conventionally used to estimate cumulative repetitive head impacts (RHI) experienced by contact sport athletes. The relationship of this measure to other estimates of head impact exposure and the potential associations of these measures with neurobehavioral functioning are unknown. We investigated the association between YoP and the Head Impact Exposure Estimate (HIEE), and whether associations between the two estimates of exposure and neurobehavioral functioning varied.

Methods:

Former American football players (N = 58; age = 37.9 ± 1.5 years) completed in-person evaluations approximately 15 years following sport discontinuation. Assessments consisted of neuropsychological assessment and structured interviews of head impact history (i.e., HIEE). General linear models were fit to test the association between YoP and the HIEE, and their associations with neurobehavioral outcomes.

Results:

YoP was weakly correlated with the HIEE, p = .005, R2 = .13. Higher YoP was associated with worse performance on the Symbol Digit Modalities Test, p = .004, R2 = .14, and Trail Making Test-B, p = .001, R2 = .18. The HIEE was associated with worse performance on the Delayed Recall trial of the Hopkins Verbal Learning Test-Revised, p = .020, R2 = .09, self-reported cognitive difficulties (Neuro-QoL Cognitive Function), p = .011, R2 = .10, psychological distress (Brief Symptom Inventory-18), p = .018, R2 = .10, and behavioral regulation (Behavior Rating Inventory of Executive Function for Adults), p = .017, R2 = .10.

Conclusions:

YoP was marginally associated with the HIEE, a comprehensive estimate of head impacts sustained over a career. Associations between each exposure estimate and neurobehavioral functioning outcomes differed. Findings have meaningful implications for efforts to accurately quantify the risk of adverse long-term neurobehavioral outcomes potentially associated with RHI.
Validation and reproducibility of a FFQ focused on pregnant women living in Northeastern Brazil
Authors: Tenório Micaely Cristina dos Santos , Wanderley Thiago Marques , Macedo Isadora Albuquerque , Vanderlei Alanna Lira Ataide , Souza Bianca Gomes de , Ataide-Silva Thays , de Oliveira Alane Cabral Menezes
Published: February 2021

Objective:

The aim of the current study is to assess the validity and reproducibility of a FFQ focused on pregnant women living in Northeastern Brazil.

Design:

Three 24-hour-dietary recalls (24 hR) and two FFQ were applied at 15-d intervals between research stages in order to confirm the validity and reproducibility of the FFQ. Validity assessment was based on Pearson’s correlation coefficient (PCC) or Spearman’s correlation coefficient (SCC) between FFQ and the mean of three 24 hR (the 24 hR was used as reference standard), whereas reproducibility assessment was based on the intraclass correlation coefficient (ICC) among FFQ, and P < 0·05 was set as significance level.

Setting:

Public health network of a capital city in Northeastern Brazil.

Participants:

Overall, 100 pregnant women were included in the study.

Results:

The PCC or SCC adopted in the validity analysis recorded the recommended values (from 0·4 and 0·7) for energy (0·44; P < 0·001), carbohydrate (0·40; P < 0·001), vitamins B2 (0·40; P < 0·001), B5 (0·40; P < 0·001), E (0·47; P < 0·001), B12 (0·48; P < 0·001), phosphorus (0·92; P < 0·001), Mg (0·81; P < 0·001), Se (0·70; P < 0·001), cholesterol (0·64; P < 0·001), saturated (0·76; P < 0·001), polyunsaturated (0·73; P < 0·001) and monounsaturated fats (0·87; P < 0·001) and fibres (0·77; P < 0·001). Mg (0·72; P < 0·001), Fe (0·65; P < 0·001), lipid (0·56; P < 0·001) and energy (0·55; P < 0·001) presented ICC within the recommended reproducibility values.

Conclusions:

The FFQ developed in the current study is a useful tool to assess the usual food intake of pregnant women.
Celebrity Suicide of a Pre-World War I Spy
Authors: Arendt Florian , Mestas Manina
Published: February 2021

Abstract. Background: Alfred Redl, a colonel in the Imperial and Royal General Staff and Deputy Director of Military Intelligence for the Austro-Hungarian Empire, was a leading figure of pre-World War I spying. The "spy of the century," as he has been called, died by suicide in Vienna on May 25, 1913. It was a big news story based on espionage, sex, and betrayal. Aim: We aimed to test whether this celebrity suicide elicited an increase in suicides – a phenomenon consistent with the "Werther effect." Method: Given daily suicide numbers were not available, we conducted archival research. Civil death registers for the city of Vienna were used to identify suicides before and after Redl's suicide. Results: The analysis indicated that more people died by suicide in the immediate aftermath and that the quantity of news reporting on Colonel Redl predicted the number of suicides per day – a pattern that is consistent with the Werther effect. Limitations: Causal interpretations are limited. Conclusion: Given the fact that the "Redl affair" is relevant for many scientific disciplines, we discuss multiple contributions to suicide research, history, media research, and research on intelligence and counter-intelligence.
Clarifying the Definition of Nonsuicidal Self-Injury
Authors: Lengel Gregory J. , Ammerman Brooke A. , Washburn Jason J.
Published: February 2021

Abstract. Background: Challenges and inconsistencies in defining nonsuicidal self-injury (NSSI) have persisted for decades, which significantly impact NSSI conceptualization and assessment in clinical and research settings and impede the field's progress. Aims: The present study aimed to solicit opinions from individuals with NSSI expertise so as to improve the operational definition and conceptualization of NSSI. Method: We asked researchers, clinicians, and graduate students with varying NSSI expertise to provide opinions on six NSSI definitional components (e.g., whether pain should be a required outcome), as well as to review 118 behaviors and indicate whether each is NSSI. Results: Responses ( N = 159) revealed good agreement on specific NSSI definitional aspects and the classification of oft-cited NSSI behaviors. However, findings also demonstrated potential discrepancies in how clinicians and researchers define NSSI when compared with specific behaviors that might be classified as NSSI. Limitations: The opinions of the study's sample may not reflect the wider NSSI field. Conclusion: Findings suggest that there is an increased need for a clear and consistent definition of NSSI and specific NSSI behaviors. There is also a need to develop new assessment measures that capture the range of NSSI behaviors that received good-to-excellent agreement among self-injury experts.
Finding SEIS North on Mars: Comparisons Between SEIS Sundial, Inertial and Imaging Measurements and Consequences for Seismic Analysis
Authors: Savoie D. , Richard A. , Goutaudier M. , Lognonné P. , Hurst K. J. , Maki J. N. , Golombek M. P. , van Driel M. , Clinton J. , Stutzmann E. , Mimoun D. , Banerdt W. B. , Williams N. R.
Published: February 2021

In this paper, we present the results obtained in the determination of the true north direction on Mars by using a gnomon on the InSight mission and compare the measurements with either the North determination from the Inertial Measurement Unit and imaging analysis. The obtained measurement has been used to populate the SEIS orientation information in the archived SEIS data. Images taken during December 2018 and January 2019 allow to determine the gnomon shadow position and length over a target. By calculating the Sun local coordinates using planetary ephemeris VSOP87, the images are used to estimate the true North direction on the landing site. By using eight different images selected, we obtain the true North direction with an accuracy up to 2.5°, which is confirmed by the IMU and imaging analysis. The true North direction is also confirmed by an image taken near local noon, when the sun crosses the meridian. The North determination precision is then discussed in view of the seismic determination of the back azimuth.
Period‐Multiplying Cycles at the Transition Between Stick‐Slip and Stable Sliding and Implications for the Parkfield Period‐Doubling Tremors
Authors: Mei Cheng , Barbot Sylvain , Wu Wei
Published: February 2021

The recurrence patterns of the Parkfield tremors with period‐multiplying slow and fast ruptures provide new insights on the physics of earthquake cycles. However, the mechanisms behind the peculiar recurrence pattern and the coupling between slow‐slip events and seismic radiations are still unclear. Here, we conduct direct‐shear experiments on polycarbonate and granite fractures under varying stress conditions to investigate the variations of rupture properties near the stability transition. Laboratory slow and fast ruptures sequences produce slip‐predictable period‐multiplying cycles with correlative acoustic energy release, stress drop, event duration, and recurrence intervals. However, gouge accumulation by damage of the granite fracture provokes changes in stiffness and stress drops ratios over multiple cycles, affecting the recurrence intervals and energy release of consecutive slip events. These findings confirm the link between low‐frequency earthquakes and underlying slow‐slip events, with period‐multiplying cycles naturally occurring near the stability transition.
The Summer Heat Balance of the Oregon Inner Shelf Over 2 Decades: Intraseasonal Variability
Authors: Lemagie E. , Kirincich A. , Lentz S.
Published: February 2021

This study examines the heat balance of the inner shelf along the US West Coast using 14 years of summer temperature and velocity observations in 15 m water depth. Previous work at this site found no year‐to‐year variability in the observed mean summer temperature change despite significant warming due to surface heat flux and variable cooling due to across‐shelf heat flux. Here, the processes that affect coastal water temperatures over time scales of days and months are investigated. Synoptic temperature variability (on time scales of several days) was predominantly due to the across‐shelf heat flux, as there was little synoptic variability in the surface heating and no evidence that an along‐shelf heat flux would close the two‐dimensional heat budget when the residual was large. The analyses suggest the across‐shelf heat flux was influenced by multiple mechanisms in addition to Ekman transport by along‐shelf winds. For example, there was a three‐layer vertical across‐shelf velocity structure 40% ± 10% of the time and during downwelling‐favorable winds there was an upwelling circulation 80% of the time. The across‐shelf heat flux was generally highest near the surface and bottom boundaries, where the velocity observations were most limited. The heat budget residual was positive most of the time, likely resulting from uncertainty due to the observational limitations. An improved understanding of the processes that control the across‐shelf heat flux and buffer temperature variability in the coastal ocean has the potential to improve predictions of coastal temperatures under climate change scenarios.
Evaluating the Relationship Between Lightning and the Large‐Scale Environment and its Use for Lightning Prediction in Global Climate Models
Authors: Etten‐Bohm Montana , Yang Junho , Schumacher Courtney , Jun Mikyoung
Published: February 2021

The objective of this study is to determine the relationship between lightning observed by the Tropical Rainfall Measuring Mission (TRMM) Lightning Imaging Sensor (LIS) and seven large‐scale environmental variables obtained from the 3‐hourly Modern‐Era Retrospective analysis for Research and Application version 2 (MERRA‐2) reanalysis in the tropics and subtropics. The large‐scale environmental variables used are: convective available potential energy (CAPE), normalized CAPE (nCAPE), lifting condensation level (LCL), column saturation fraction (r), 700‐hPa omega, low‐level wind shear (LS) from 900 to 700 hPa, and deep wind shear (DS) from 900 to 300 hPa. All environmental variables show a significant shift toward larger values when lightning is present except for shear. DS decreases when lightning is present, while LS shows little mean change. However, strong geographical differences exist in the relationship between the environmental variables and lightning occurrence, particularly between land and ocean and the tropics and subtropics. Using a logistic regression, a lightning parameterization for global climate models (GCMs) is created using the above environmental variables as predictors while also adding geographic indicators (coast, slope, and latitude) and terms representing interactions between the predictors. The logistic regression predicts lightning occurrence accurately up to 86% of the time and is further applied to MERRA‐2. While there are regions of overprediction and underprediction, the lightning parameterization performance shows promising potential for use in GCMs.
Numerical Simulation of Lunar Seismic Wave Propagation: Investigation of Subsurface Scattering Properties Near Apollo 12 Landing Site
Authors: Onodera K. , Kawamura T. , Tanaka S. , Ishihara Y. , Maeda T.
Published: February 2021

One of the most critical issues associated with the analysis of lunar seismic data is the intense scattering, which prevents precise seismic phase identifications, thereby resulting in poor constraints on the internal structure of the Moon. Although some studies estimated subsurface scattering properties from analyses of the Apollo seismic data, the properties have large uncertainties and are still open issues to be resolved to improve the inner structure model of the Moon. While the previous studies tried to constrain the scattering features within the lunar crust mainly from data analysis, this study estimated them from a numerical approach. We constrained the scattering properties near Apollo 12 landing site by conducting seismic wave propagation simulations under various parameter settings and comparing the synthetics with the data. As a result, we succeeded in reproducing seismic signals excited by the Apollo artificial impacts. This led to a constraint on the scattering properties, such as typical scale and thickness of heterogeneity, around the Apollo 12 landing site. The derived structure suggests that the intense scattering structure exists down to 20 km at the northern portion of the region of the Apollo 12 landing site, and to 10 km at the southern region from the landing site. In addition, our model requires a smaller P‐ and S‐wave velocity ratio (1.2–1.4) compared with those conventionally considered (>1.73). This implies a dry and porous environment consistent with laboratory measurements of terrestrial samples and reasonable with the generalized lunar environment.
Time, Hydrologic Landscape, and the Long‐Term Storage of Peatland Carbon in Sedimentary Basins
Authors: Large David J. , Marshall Chris , Jochmann Malte , Jensen Maria , Spiro Baruch F. , Olaussen Snorre
Published: February 2021

Peatland carbon may enter long‐term storage in sedimentary basins preserved as either coal or lignite. The time required to account for the carbon in 1–10 m thick coal seams must represent 105–106 years, an order of magnitude more than previously assumed. To understand the process by which this happens requires extrapolation of our understanding of peatland carbon accumulation over timescales that greatly exceed those of Holocene peat. We analyze the consequences of extrapolating peat growth to periods of 106 years. We deduce that that key to sustained peat growth are hydrologic landscapes that can maintain a saturated peat body above the level of clastic deposition. Contrary to current stratigraphic frameworks, we conclude that the generation of accommodation space at low rates of 0.1–0.2 mm/yr can adequately accommodate thick peat accumulation over periods >105 years. However, generation of accommodation space at rates >0.5 mm/yr cannot. The low rates that permit accommodation of thick peat are typical of the rates of subsidence in specific tectonic settings, particularly foreland basins, and this has implications for our understanding of the links between terrestrial carbon burial, tectonics and the carbon cycle. The long‐term stability of extensive peatland required to form coal also requires sediment bypass, modifying basin wide sediment transport and deposition. Limits to peatland growth under very low accommodation rates must exist but the relative importance of the limiting process is not understood. Finally, we discuss the consequences of these factors for predicting the future of the peatland carbon reservoir.
Evolution of Coseismic and Post‐seismic Landsliding After the 2015 Mw 7.8 Gorkha Earthquake, Nepal
Authors: Kincey Mark E. , Rosser Nick J. , Robinson Tom R. , Densmore Alexander L. , Shrestha Ram , Pujara Dammar Singh , Oven Katie J. , Williams Jack G. , Swirad Zuzanna M.
Published: February 2021

Coseismic landslides are a major hazard associated with large earthquakes in mountainous regions. Despite growing evidence for their widespread impacts and persistence, current understanding of the evolution of landsliding over time after large earthquakes, the hazard that these landslides pose, and their role in the mountain sediment cascade remains limited. To address this, we present the first systematic multi‐temporal landslide inventory to span the full rupture area of a large continental earthquake across the pre‐, co‐ and post‐seismic periods. We focus on the 3.5 years after the 2015 Mw 7.8 Gorkha earthquake in Nepal and show that throughout this period both the number and area of mapped landslides have remained higher than on the day of the earthquake itself. We document systematic upslope and northward shifts in the density of landsliding through time. Areas where landslides have persisted tend to cluster in space, but those areas that have returned to pre‐earthquake conditions are more dispersed. While both pre‐ and coseismic landslide locations tend to persist within mapped post‐earthquake inventories, a wider population of newly activated but spatially dispersed landslides has developed after the earthquake. This is particularly important for post‐earthquake recovery plans that are typically based on hazard assessments conducted immediately after the earthquake and thus do not consider the evolving landslide hazard. We show that recovery back to pre‐earthquake landsliding rates is fundamentally dependent on how that recovery is defined and measured. Clarity around this definition is particularly important for informing a comprehensive approach to post‐earthquake landslide hazard and risk.
The Impacts of a Subglacial Discharge Plume on Calving, Submarine Melting, and Mélange Mass Loss at Helheim Glacier, South East Greenland
Authors: Everett Alistair , Murray Tavi , Selmes Nick , Holland David , Reeve Dominic E.
Published: February 2021

Almost half of the Greenland ice sheet's mass loss occurs through iceberg calving at marine terminating glaciers. The presence of buoyant subglacial discharge plumes at these marine termini are thought to increase mass loss both through submarine melting and by undercutting that consequently increases calving rates. Plume models are used to predict submarine melting and undercutting. However, there are few observations that allow these relationships to be tested. Here, we use airborne lidar from the terminus of Helheim Glacier, SE Greenland to measure the bulge induced at the surface by the upwelling plume. We use these measurements to estimate plume discharge rates using a high‐resolution, three‐dimensional plume model. Multiyear observations of the plume are compared to a record of calving from camera and icequake data. We find no evidence to suggest that the presence of a plume, determined by its visibility at the surface, increases the frequency of major calving events and also show that mass loss at the terminus driven directly by plume discharge is significantly less than mass loss from major calving events. The results suggest that the contribution of direct plume‐driven mass loss at deep marine‐terminating glaciers may be less than at shallower termini.
Validation of the SMOS Mission for Space Weather Operations: The Potential of Near Real‐Time Solar Observation at 1.4 GHz
Authors: Flores‐Soriano M. , Cid C. , Crapolicchio R.
Published: February 2021

Soil Moisture and Ocean Salinity (SMOS) is an ESA mission observing Earth at 1.4 GHz with full polarimetry. SMOS images are affected by a noise of solar origin produced by the Sun appearing in the antenna's field of view. In this paper, we study whether this solar signal is of any use for scientific and space weather observations. We analyze the response of the SMOS Sun brightness temperature (BT) to thermal and nonthermal solar emissions, and compare them with observations from ground radio telescopes, GOES X‐ray flares, and CMEs from SOHO/LASCO. We find that the SMOS Sun BT can detect weak variations in the solar emission such as the progress of the 11‐year activity cycle, the solar rotation, and the thermal emission from flares. Solar radio bursts detected by the SMOS Sun BT are generally observed during flares from the visible hemisphere of the Sun that are associated with a CME. We also find a correlation between the amount of solar flux released at 1.4 GHz and the speed, angular width, and kinetic energy of the CMEs. We conclude that the unique capability of the SMOS mission to perform 24 h near real‐time observation of the Sun with full polarimetry makes it a promising instrument for monitoring solar interferences affecting GNSS, radar, and L‐band wireless communications, as well as for early assessment of flares geoeffectiveness. Nevertheless, the current limitations of the solar data as byproduct of the SMOS data reduction pipeline make it necessary to create a dedicated product for solar observations.
A Physically Based Model for Preferential Water Flow and Solute Transport in Drained Agricultural Fields
Authors: Holbak M. , Abrahamsen P. , Hansen S. , Diamantopoulos E.
Published: February 2021

Preferential water flow and associated solute transport in agricultural soils may influence the quality of groundwater and surface waters like streams and lakes. This is due to the rapid transport of agrochemicals, immediately after application, through subsurface drainpipes and surface water. Multiple field experiments attribute this to the occurrence of continuously connected pathways, called here biopores, connecting the soil surface directly with the drainpipes. We developed a physically based model describing preferential flow and transport in biopores directly connecting the upper soil layers with the drainpipes or deeper layers of the soil matrix. Based on field investigations, biopores with specific characteristics can be parameterized as classes with different vertical and horizontal distributions. Water flow and solute transport in biopores are described with a simple mass balance approach assuming instantaneous movement. The model was tested against experimental data from a column experiment with an artificial biopore and showed good results in simulating biopore flow initiation dynamics. However, further field and laboratory experiments are needed to validate the model across the soil profile. We illustrate the performance of the new approach, by conducting five theoretical simulations assuming a two‐dimensional simulation domain with different biopore parametrizations, from none to several different classes. The simulation results agreed with experimental observations reported in the literature, indicating rapid transport from the soil to the drainpipes. Furthermore, the different biopore parametrizations resulted in distinctly different leaching patterns, raising the expectation that biopore properties could be estimated or constrained based on observed leaching data and direct measurements.
Quantifying Shallow Overland Flow Patterns Under Laboratory Simulations Using Thermal and LiDAR Imagery
Authors: Danino Din , Svoray Tal , Thompson Sally , Cohen Ariel , Crompton Octavia , Volk Elazar , Argaman Eli , Levi Asher , Cohen Yafit , Narkis Kfir , Assouline Shmuel
Published: February 2021

Desertification processes pose a global environmental threat, impacting 61 × 106 km2 of the terrestrial land area. Changes in overland flow patterns and consequent rainwater redistribution in drylands present a potential pathway to desertification, because vegetation often relies on water inputs from runoff to sustain growth under insufficient rainfall conditions. Of particular importance are the very shallow overland flows that redistribute water, nutrients, and biological matter within arid landscapes. However, characterizing overland flow patterns remains challenging, due to their very shallow depths, their distributed nature, and the poor understanding of how these flows interact with the underlying rough soil surface. This paper describes how coupling thermal images of shallow overland flows with light detection and ranging (LiDAR) scanning of the underlying soil surface in 1 m2 experimental trays allows spatial patterns of shallow overland flow to be quantified. Laboratory experiments were used to explore the behaviors of shallow overland flow as mean slope gradients and soil roughness were varied. The results show that these imaging techniques are able to capture differences in flow patterns arising across soil surfaces with varying slope, roughness, and spatial variation in infiltration properties. Several spatial indices characterizing overland flow patterns were found to correlate with runoff volume. The presence of high permeability soil patches substantially regulated overland flow. A next logical step would be to apply the thermal and LiDAR measurement techniques to the hillslope scale.
The Alkalinity Trap at the Bottom of the World
Authors: Thompson Elizabeth
Published: February 2021

Tiny microorganisms in the Southern Ocean affect the way the rest of the world’s seas respond to carbon dioxide.