bluuebunny/crossref_metadata_2025 huggingface dataset:
A Relaxation of Üresin and Dubois’ Asynchronous Fixed-Point Theory in Agda
Authors: Daggitt Matthew L. , Zmigrod Ran , Griffin Timothy G.
Published: December 2019

Üresin and Dubois’ paper “Parallel Asynchronous Algorithms for Discrete Data” shows how a class of synchronous iterative algorithms may be transformed into asynchronous iterative algorithms. They then prove that the correctness of the resulting asynchronous algorithm can be guaranteed by reasoning about the synchronous algorithm alone. These results have been used to prove the correctness of various distributed algorithms, including in the fields of routing, numerical analysis and peer-to-peer protocols. In this paper we demonstrate several ways in which the assumptions that underlie this theory may be relaxed. Amongst others, we (i) expand the set of schedules for which the asynchronous iterative algorithm is known to converge and (ii) weaken the conditions that users must prove to hold to guarantee convergence. Furthermore, we demonstrate that two of the auxiliary results in the original paper are incorrect, and explicitly construct a counter-example. Finally, we also relax the alternative convergence conditions proposed by Gurney based on ultrametrics. Many of these relaxations and errors were uncovered after formalising the work in the proof assistant Agda. This paper describes the Agda code and the library that has resulted from this work. It is hoped that the library will be of use to others wishing to formally verify the correctness of asynchronous iterative algorithms.
Multimodal Imaging Techniques Show Differences in Homing Capacity Between Mesenchymal Stromal Cells and Macrophages in Mouse Renal Injury Models
Authors: Taylor Arthur , Sharkey Jack , Harwood Rachel , Scarfe Lauren , Barrow Michael , Rosseinsky Matthew J. , Adams Dave J. , Wilm Bettina , Murray Patricia
Published: December 2019

Purpose

The question of whether mesenchymal stromal cells (MSCs) home to injured kidneys remains a contested issue. To try and understand the basis for contradictory findings reported in the literature, our purpose here was to investigate whether MSC homing capacity is influenced by administration route, the type of injury model used, and/or the presence of exogenous macrophages.

Procedures

To assess the viability, whole-body biodistribution, and intra-renal biodistribution of MSCs, we used a multimodal imaging strategy comprising bioluminescence and magnetic resonance imaging. The effect of administration route (venous or arterial) on the ability of MSCs to home to injured renal tissue, and persist there, was assessed in a glomerular injury model (induced by the nephrotoxicant, Adriamycin) and a tubular injury model induced by ischaemia-reperfusion injury (IRI). Exogenous macrophages were used as a positive control because these cells are known to home to injured mouse kidneys. To assess whether the homing capacity of MSCs can be influenced by the presence of exogenous macrophages, we used a dual-bioluminescence strategy that allowed the whole-body biodistribution of the two cell types to be monitored simultaneously in individual animals.

Results

Following intravenous administration, no MSCs were detected in the kidneys, irrespective of whether the mice had been subjected to renal injury. After arterial administrationviathe left cardiac ventricle, MSCs transiently populated the kidneys, but no preferential homing or persistence was observed in injured renal tissue after unilateral IRI. An exception was when MSCs were co-administered with exogenous macrophages; here, we observed some homing of MSCs to the injured kidney.

Conclusions

Our findings strongly suggest that MSCs do not home to injured kidneys.
Power Analysis and Sample Size Planning in ANCOVA Designs
Authors: Shieh Gwowen
Published: December 2019

The analysis of covariance (ANCOVA) has notably proven to be an effective tool in a broad range of scientific applications. Despite the well-documented literature about its principal uses and statistical properties, the corresponding power analysis for the general linear hypothesis tests of treatment differences remains a less discussed issue. The frequently recommended procedure is a direct application of the ANOVA formula in combination with a reduced degrees of freedom and a correlation-adjusted variance. This article aims to explicate the conceptual problems and practical limitations of the common method. An exact approach is proposed for power and sample size calculations in ANCOVA with random assignment and multinormal covariates. Both theoretical examination and numerical simulation are presented to justify the advantages of the suggested technique over the current formula. The improved solution is illustrated with an example regarding the comparative effectiveness of interventions. In order to facilitate the application of the described power and sample size calculations, accompanying computer programs are also presented.
Mercury dynamics in macroinvertebrates in relation to environmental factors in a highly impacted tropical estuary: Buenaventura Bay, Colombian Pacific
Authors: Gamboa-García Diego Esteban , Duque Guillermo , Cogua Pilar , Marrugo-Negrete José Luis
Published: December 2019

The environmental health of Buenaventura Bay, a highly impacted tropical estuary, is influenced by numerous human activities, including mining upstream. Large- and small-scale fishing plays an important role in the local economy, so we investigated the dynamic processes of bioaccumulation of mercury at basal trophic levels. Four samples were taken at each of the four locations in Buenaventura Bay during each of the four seasons of 2015. We measured the total mercury content (T-Hg, dry weight) in sediments and in muscle tissue across 17 macroinvertebrate species. The most abundant were the blue crab (C. arcuatus) and the mantis shrimp (S. aculeata aculeata). Blue crab showed an average muscle T-Hg value ​​exceeding the limit of 0.2 g·g-1, which is the maximum T-Hg level suggested for food consumption by vulnerable humans and populations: pregnant women, children, and the community that feeds from this source of protein on a daily basis. It was found that, 6.22% of individuals exceeded the 0.5 g·g-1level, which is the maximum T-Hg level suggested for food consumption by the general population: the population that consumes it sporadically. Significantly high values ​​of T-Hg in blue crab and mantis shrimp occurred during low salinity conditions in the estuary, suggesting that Hg mainly originates from river runoff during the rainy season. Nevertheless, the biota-sediment accumulation factor (BSAF) was favored in high salinity, which could mean greater availability of Hg for higher levels of the estuarine food web in the dry season and in marine waters. In general, the T-Hg levels in some samples exceeded 0.2 g·g−1. Therefore this pollutant must be monitored due to its biomagnification potential and as a threat to human health, especially that for the local population of fishermen and their families.
A randomised comparison of the effect of haemodynamic monitoring with CardioMEMS in addition to standard care on quality of life and hospitalisations in patients with chronic heart failure
Authors: Brugts J. J. , Veenis J. F. , Radhoe S. P. , Linssen G. C. M. , van Gent M. , Borleffs C. J. W. , van Ramshorst J. , van Pol P. , Tukkie R. , Spee R. F. , Emans M. E. , Kok W. , van Halm V. , Handoko L. , Beeres S. L. M. A. , Post M. C. , Boersma E. , Lenzen M. J. , Manintveld O. C. , Koffijberg H. , van Baal P. , Versteegh M. , Smilde T. D. , van Heerebeek L. , Rienstra M. , Mosterd A. , Delnoy P. P. H. , Asselbergs F. W. , Brunner-La Rocca H. P. , de Boer R. A.
Published: December 2019

Background

Assessing haemodynamic congestion based on filling pressures instead of clinical congestion can be a way to further improve quality of life (QoL) and clinical outcome by intervening before symptoms or weight gain occur in heart failure (HF) patients. The clinical efficacy of remote monitoring of pulmonary artery (PA) pressures (CardioMEMS; Abbott Inc., Atlanta, GA, USA) has been demonstrated in the USA. Currently, the PA sensor is not reimbursed in the European Union as its benefit when applied in addition to standard HF care is unknown in Western European countries, including the Netherlands.

Aims

To demonstrate the efficacy and cost-effectiveness of haemodynamic PA monitoring in addition to contemporary standard HF care in a high-quality Western European health care system.

Methods

The current study is a prospective, multi-centre, randomised clinical trial in 340 patients with chronic HF (New York Heart Association functional class III) randomised to HF care including remote monitoring with the CardioMEMS PA sensor or standard HF care alone. Eligible patients have at least one hospitalisation for HF in 12 months before enrolment and will be randomised in a 1:1 ratio. Minimum follow-up will be 1 year. The primary endpoint is the change in QoL as measured by the Kansas City Cardiomyopathy Questionnaire (KCCQ). Secondary endpoints are the number of HF hospital admissions and changes in health status assessed by EQ-5D-5L questionnaire including health care utilisation and formal cost-effectiveness analysis.

Conclusion

The MONITOR HF trial will evaluate the efficacy and cost-effectiveness of haemodynamic monitoring by CardioMEMS in addition to standard HF care in patients with chronic HF. Clinical Trial Registration number NTR7672.
The Myth of McMindfulness
Authors: Anālayo Bhikkhu
Published: December 2019

This article examines to what extent the teaching of mindfulness-based stress reduction (MBSR) can accurately be referred to by the term “McMindfulness.” The application of this term appears to rest on the expectation that teachers of MBSR and similar mindfulness programs, in order to be true to their Buddhist heritage, should inculcate political awareness in their patients, motivating them to resist the neoliberal capitalist system. Moreover, another assumption seems to be that present-moment awareness, viewed as another departure from ancient Indian Buddhism, prevents critical thinking and thereby supports obedient submission to exploitative conditions. Closer examination shows that expecting mindfulness teachers to stimulate political activism is not in keeping with relevant Buddhist antecedents. The relevant sources even testify to the employment of mindfulness for mere health benefits already in ancient India. Besides, the same textual sources show that mindfulness of the present moment is not a later innovation. The belief that such mindful presence disables critical thinking appears to mistake the goal of the cultivation of mindfulness for the mere absence of thoughts. At least as far as MBSR and related programs in healthcare are concerned, the term “McMindfulness” is not justified and its recent indiscriminate application to any contemporary mindfulness practice appears to have turned it into a myth. Rather than being merely a tool to ensure subservience to the neoliberal capitalist system, in view of the impending climate catastrophe, mindfulness can offer an important resource to face the ravages caused by unbridled exploitation of the environment.
Experimental Phenomenology in Mindfulness Research
Authors: Lundh Lars-Gunnar
Published: December 2019

The present paper argues that experimental phenomenology has an important role to play in research on mindfulness. Experimental phenomenology is defined as a subcategory of phenomenology (defined as the science of our subjective experience of being in the world), which explores the effects of intentional variations of subjective experiencing (direction of attention and choice of attitude) on subsequent experience. To count as experimental phenomenology, both the independent and dependent variable have to be phenomenological. Because mindfulness involves paying attention to present experience with a specific attitude, it is well suited for experimental-phenomenological research. What makes experimental phenomenology into a scientific endeavor is the intersubjective nature of this kind of study: potential effects described by one person can be subjected to replication both by the same person, and by other persons. Also, conclusions drawn on the basis of this kind of study are hypothetical and provisional, and may be modified or specified on the basis of further study. In this paper, the principles of experimental phenomenology are illustrated by (a) variations of a given mindfulness practice (the body scan), and (b) the construction of a personalized mindfulness practice (mindful driving). Finally, three varieties of experimental phenomenology in research on mindfulness are discussed: (1) the use of qualitative methods to analyze mindfulness practices and their potential effects, (2) idiographic research with the use of single-subject designs and experience sampling, and (3) randomized controlled studies of the effects of mindfulness practices on present experience.
TiN Paper for Ultrafast-Charging Supercapacitors
Authors: Yao Bin , Li Mingyang , Zhang Jing , Zhang Lei , Song Yu , Xiao Wang , Cruz Andrea , Tong Yexiang , Li Yat
Published: December 2019

Ultrafast-charging energy storage devices are attractive for powering personal electronics and electric vehicles. Most ultrafast-charging devices are made of carbonaceous materials such as chemically converted graphene and carbon nanotubes. Yet, their relatively low electrical conductivity may restrict their performance at ultrahigh charging rate. Here, we report the fabrication of a porous titanium nitride (TiN) paper as an alternative electrode material for ultrafast-charging devices. The TiN paper shows an excellent conductivity of 3.67 × 104 S m−1, which is considerably higher than most carbon-based electrodes. The paper-like structure also contains a combination of large pores between interconnected nanobelts and mesopores within the nanobelts. This unique electrode enables fast charging by simultaneously providing efficient ion diffusion and electron transport. The supercapacitors (SCs) made of TiN paper enable charging/discharging at an ultrahigh scan rate of 100 V s−1 in a wide voltage window of 1.5 V in Na2SO4 neutral electrolyte. It has an outstanding response time with a characteristic time constant of 4 ms. Significantly, the TiN paper-based SCs also show zero capacitance loss after 200,000 cycles, which is much better than the stability performance reported for other metal nitride SCs. Furthermore, the device shows great promise in scalability. The filtration method enables good control of the thickness and mass loading of TiN electrodes and devices.
Geographic distribution of cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations in Saudi Arabia
Authors: Banjar Hanaa , Al-Mogarri Ibrahim , Nizami Imran , Al-Haider Sami , AlMaghamsi Talal , Alkaf Sara , Al-Enazi Abdulaziz , Moghrabi Nabil
Published: December 2019

Introduction:

Cystic fibrosis (CF) has been reported before in Saudi Arabia and the Gulf area. It has been found that screening for 10 most common cystic fibrosis transmembrane conductance regulator (CFTR) mutations can detect 80% of positive CFTR cases.

Objectives:

To determine the geographic distribution of the most common CFTR variants in 5 regions of Saudi Arabia.

Methodology:

A retrospective chart review of all CFTR variants conducted from January 1, 1992 to December 1, 2017.

Results:

The ten most common CFTR mutations in the Saudi population were as follows: p.Gly473GlufsX54 (17%), p.Phe508del (12%), p.Ile1234Val (12%), 3120+1G > A (11%), 711+1G > T (9%), p.His139Leu (6%), p.Gln637Hisfs (5%), p.Ser549Arg (3%), p.N1303K (3%), and delExon19-21 (2%) along with other variants 79 (20%). In terms of the highest frequency, the c.2988+1G > A (3120+1G > A) variant was found in the eastern province (7.3%) of Saudi Arabia, the c.1418delG (p.Gly473GlufsX54) variant in the northern province (6.8%), the c.579+1G > T (711+1G > T) variant in the southern province (4.8%), the c.3700A > G (p.Ile1234Val) variant in the central province (4.8%), and c.1521_1523delCTT (p.Phe508del) variant in the western province (4.3%).

Conclusion:

The eastern and the northern provinces have the highest prevalence of CF, with the c.2988+1G > A (3120+1G > A) and c.1418delG (p.Gly473GlufsX54) variants showing the highest distribution in the Saudi CF population, which may reflect the effect of consanguinity within the same tribe. Proper family screening and counseling should be emphasized.
Augmentation Phalloplasty for Acquired Penile Shortening: A Systematic Review of Techniques, Outcomes, Patient Satisfaction, and Limitations
Authors: Abu-Ghname Amjed , Banuelos Joseph , Davis Matthew J. , Kreutz-Rodrigues Lucas , Morrison Shane D. , Vyas Krishna S.
Published: December 2019

Introduction

Although an infrequent cause of small penile size in adult men, acquired penile shortening represents a particular reconstructive challenge due to preexisting penile anatomic deformities.

Aim

With numerous techniques being performed, the purpose of our study is to assess available literature on length enhancement procedures used for acquired penile shortening deformities.

Methods

A systematic review was performed using the guidelines outlined in the Preferred Reporting Items for Systematic reviews and Meta-analyses. Medline/PubMed, Scopus, and Cochrane Databases were used to identify papers on augmentation Phalloplasty in non-transgender males with acquired penile shortening from 1990 to 2018.

Main Outcome Measure

Outcomes, complications, and patient-reported satisfaction were analyzed.

Results

12 articles, involving 931 patients and 8 primary procedures, met our inclusion criteria. The majority of articles had level of evidence of 4 (83%) and Newcastle Ottawa Scale score of 6 (92%, moderate risk of bias). All studies reported mean penile length gain; however, inconsistent methodology was used when measuring penile dimensions. Mean length gain ranged from 0.6 to 6.4 cm. Overall, the mean complication rate for all techniques ranged from 0% to 50%. Post-operative satisfaction was reported in 10 (83%) studies, 7 of which used a validated scale. Patients were generally satisfied, with reported satisfaction rates ranging from 77% to 100%.

Clinical Implications

While numerous procedures have been described, the significant limitations in the available data preclude identifying a single superior procedure.

Strengths & Limitations

The significant heterogeneity in the reported literature is a limitation of this study and highlights the need for standardized reporting. However, this study is the first to analyze augmentation phalloplasty literature in the setting of acquired penile shortening.

Conclusion

Augmentation phalloplasty techniques for acquired penile shortening are evolving and are continuously being modified; best-practice guidelines are crucial to achieve safe and satisfactory outcomes in this population.
Investigation on Actuation Performance of Continuous Fiber Reinforced Piezoelectric Composite Actuator
Authors: Ma X. , Zhou B. , Xue S. F.
Published: December 2019

In this paper, a novel continuous fiber reinforced piezoelectric composite (CFRPC) actuator is proposed to improve the stability and reliability of piezoelectric actuators. A piezoelectric driving structure composed of a cantilever beam and the CFRPC actuator is utilized to research the actuation performance of the CFRPC actuator. The expression of the equivalent moment for the CFRPC actuator is obtained using the equivalent load method and electro-mechanical coupling theory. Based on Euler-Bernoulli beam theory, the analytical expression of the deflection for the cantilever beam is derived. The accuracy of the obtained analytical expressions is demonstrated by finite element simulation as well as published experimental results. The actuation performance of the CFRPC actuator is investigated through the analytical expressions of the equivalent moment and deflection. The results show that the key parameters such as driving voltage, fiber volume fraction, cantilever beam height, actuator height, actuator length and actuator position have great influence on the actuation performance of the CFRPC actuator. The CFRPC actuator has good mechanical and electrical properties, and has a wide application prospect in the field of structural shape control.
New approach to simplifying and optimising acute malnutrition treatment in children aged 6–59 months: the OptiMA single-arm proof-of-concept trial in Burkina Faso
Authors: Daures Maguy , Phelan Kevin , Issoufou Mariama , Kouanda Séni , Sawadogo Ousmane , Issaley Kader , Cazes Cecile , Séri Benjamin , Ouaro Bertine , Akpakpo Bruno , Mendiboure Vincent , Shepherd Susan , Becquet Renaud
Published: December 2019

The Optimising treatment for acute MAlnutrition (OptiMA) strategy trains mothers to use mid upper arm circumference (MUAC) bracelets for screening and targets treatment to children with MUAC < 125 mm or oedema with one therapeutic food at a gradually reduced dose. This study seeks to determine whether OptiMA conforms to SPHERE standards (recovery rate > 75 %). A single-arm proof-of-concept trial was conducted in 2017 in Yako district, Burkina Faso including children aged 6–59 months in outpatient health centres with MUAC < 125 mm or oedema. Outcomes were stratified by MUAC category at admission. Multivariate survival analysis was carried out to identify variables predictive of recovery. Among 4958 children included, 824 (16·6 %) were admitted with MUAC < 115 mm or oedema, 1070 (21·6 %) with MUAC 115–119 mm and 3064 (61·8 %) with MUAC 120–124 mm. The new dosage was correctly implemented at all visits for 75·9 % of children. Global recovery was 86·3 (95 % CI 85·4, 87·2) % and 70·5 (95 % CI 67·5, 73·5) % for children admitted with MUAC < 115 mm or oedema. Average therapeutic food consumption was 60·8 sachets per child treated. Recovery was positively associated with mothers trained to use MUAC prior to child’s admission (adjusted hazard ratio 1·09; 95 % CI 1·01, 1·19). OptiMA was successfully implemented at the scale of an entire district under ‘real-life’ conditions. Programme outcomes exceeded SPHERE standards, but further study is needed to determine if increasing therapeutic food dosages for the most severely malnourished will improve recovery.
Evaluation of the Dreicer runaway generation rate in the presence of high- impurities using a neural network
Authors: Hesslow L. , Unnerfelt L. , Vallhagen O. , Embreus O. , Hoppe M. , Papp G. , Fülöp T.
Published: December 2019

Integrated modelling of electron runaway requires computationally expensive kinetic models that are self-consistently coupled to the evolution of the background plasma parameters. The computational expense can be reduced by using parameterized runaway generation rates rather than solving the full kinetic problem. However, currently available generation rates neglect several important effects; in particular, they are not valid in the presence of partially ionized impurities. In this work, we construct a multilayer neural network for the Dreicer runaway generation rate which is trained on data obtained from kinetic simulations performed for a wide range of plasma parameters and impurities. The neural network accurately reproduces the Dreicer runaway generation rate obtained by the kinetic solver. By implementing it in a fluid runaway-electron modelling tool, we show that the improved generation rates lead to significant differences in the self-consistent runaway dynamics as compared to the results using the previously available formulas for the runaway generation rate.
Use of information sources regarding medicine side effects among the general population: a cross-sectional survey
Authors: O’Donovan Bernadine , Rodgers Ruth M. , Cox Anthony R. , Krska Janet
Published: December 2019

Aim:

To determine the use and perceived value of different information sources that patients may use to support identification of medicine side effects; to explore associations between coping styles and use of information sources.

Background:

Side effects from medicines can have considerable negative impact on peoples’ daily lives. As a result of an ageing UK population and attendant multi-morbidity, an increasing number of medicines are being prescribed for patients, leading to increased risk of unintended side effects.

Methods:

A cross-sectional survey of patients who use medicine, recruited from community pharmacies. The survey sought views on attributes of various information sources, their predicted and actual use, incorporating a shortened Side Effects Coping Questionnaire (SECope) scale and the abbreviated Miller Behavioural Style Scale (MBSS).

Findings:

Of 935 questionnaires distributed, 230 (25.0%) were returned, 61.3% from females; 44.7% were retired and 84.6% used at least one medicine regularly. 69.6% had experienced a side effect, resulting in 57.5% of these stopping the medicine. Patient information leaflets (PILs) and GPs were both predicted and actually most widely used sources, despite GPs being judged as relatively less accessible and PILs less trustworthy, particularly by regular medicine users. Pharmacists, considered both easy to access and trustworthy, were used by few in practice, while the internet was considered easy to access, but less trustworthy and was also little used. SECope sub-scales for non-adherence and information seeking showed positive associations with stopping a medicine and seeking information from a health professional. More high monitors than low monitors stopped a medicine themselves, but there were no differences in use of information sources. Information seeking following a side effect is a common strategy, potentially predicted by the SECope, but not the MBSS. Limited GP accessibility could contribute to high internet use. Further research could determine how the trustworthiness of PILs can be improved.
Future Evolution of Greenland's Marine‐Terminating Outlet Glaciers
Authors: Catania G. A. , Stearns L. A. , Moon T. A. , Enderlin E. M. , Jackson R. H.
Published: December 2019

Mass loss from the Greenland ice sheet (GrIS) has increased over the last two decades in response to changes in global climate, motivating the scientific community to question how the GrIS will contribute to sea‐level rise on timescales that are relevant to coastal communities. Observations also indicate that the impact of a melting GrIS extends beyond sea‐level rise, including changes to ocean properties and circulation, nutrient and sediment cycling, and ecosystem function. Unfortunately, despite the rapid growth of interest in GrIS mass loss and its impacts, we still lack the ability to confidently predict the rate of future mass loss and the full impacts of this mass loss on the globe. Uncertainty in GrIS mass loss projections in part stems from the nonlinear response of the ice sheet to climate forcing, with many processes at play that influence how mass is lost. This is particularly true for outlet glaciers in Greenland that terminate in the ocean because their flow is strongly controlled by multiple processes that alter their boundary conditions at the ice‐atmosphere, ice‐ocean, and ice‐bed interfaces. Many of these processes change on a range of overlapping timescales and are challenging to observe, making them difficult to understand and thus missing in prognostic ice sheet/climate models. For example, recent (beginning in the late 1990s) mass loss via outlet glaciers has been attributed primarily to changing ice‐ocean interactions, driven by both oceanic and atmospheric warming, but the exact mechanisms controlling the onset of glacier retreat and the processes that regulate the amount of retreat remain uncertain. Here we review the progress in understanding GrIS outlet glacier sensitivity to climate change, how mass loss has changed over time, and how our understanding has evolved as observational capacity expanded. Although many processes are far better understood than they were even a decade ago, fundamental gaps in our understanding of certain processes remain. These gaps impede our ability to understand past changes in dynamics and to make more accurate mass loss projections under future climate change. As such, there is a pressing need for (1) improved, long‐term observations at the ice‐ocean and ice‐bed boundaries, (2) more observationally constrained numerical ice flow models that are coupled to atmosphere and ocean models, and (3) continued development of a collaborative and interdisciplinary scientific community.
Widespread Shallow Water Ice on Mars at High Latitudesand Midlatitudes
Authors: Piqueux Sylvain , Buz Jennifer , Edwards Christopher S. , Bandfield Joshua L. , Kleinböhl Armin , Kass David M. , Hayne Paul O. ,   The MCS,   THEMIS Teams
Published: December 2019

We derive the depth of the water ice table on Mars by fitting seasonal surface temperature trends acquired by the Mars Climate Sounder and Thermal Emission Imaging System with a two‐layer regolith model assuming frozen H2O as the lower material. Our results are consistent with widespread water ice at latitudes as low as 35°N/45°S buried sometimes a few centimeters below sand‐like material, with high lateral ice depth variability, and correlated with periglacial features. While several investigations have already predicted, identified, and characterized some properties of near‐surface ice on Mars, our results constitute a significant advance in the context of the upcoming crewed exploration because (1) they focus on very shallow depths accessible with limited equipment, (2) they provide continuous regional coverage including the midlatitudes, and (3) they yield moderate spatial resolution maps (3 ppd) relevant to landing site selection studies.
Drainage and Sedimentary Responses to Dynamic Topography
Authors: Ding Xuesong , Salles Tristan , Flament Nicolas , Mallard Claire , Rey Patrice F.
Published: December 2019

Dynamic topography due to mantle flow contributes to shaping Earth's evolving landscapes by affecting sediment routing, which has rarely been explored in source‐to‐sink contexts. Here we design a generic model to investigate the impact of dynamic topography on both landscape evolution and stratigraphic formations. An imposed wave of dynamic topography propagates laterally under a fixed continent, exerting transient surface uplift and subsidence. We find that a migrating dynamic topography can induce significant drainage reorganizations and affect sediment routing from source to sink. Variations in sediment supply driven by the lateral migrating dynamic topography contribute to the formation of diachronous unconformities along the margin. The predicted sediment flux histories are then put into perspective with the Cretaceous sedimentary records along the Southern African margins. Finally, we demonstrate that correlating offshore depositional hiatuses and unconformities has the potential to constrain the spatiotemporal evolution of past dynamic topography events.
Post‐Collapse Gravity Increase at the Summit of Kīlauea Volcano, Hawaiʻi
Authors: Poland Michael P. , de Zeeuw‐van Dalfsen Elske , Bagnardi Marco , Johanson Ingrid A.
Published: December 2019

We conducted gravity surveys of the summit area of Kīlauea Volcano, Hawaiʻi, in November 2018 and March 2019, with the goal of determining whether there was any mass change at depth following the volcano's May–August 2018 caldera collapse. Surface deformation between the two surveys was minimal, but we measured a gravity increase (maximum 44 μGal) centered on the caldera that can be modeled as mass accumulation in a region ~1 km beneath the surface. We interpret this mass increase to be mostly magma accumulation in void space that was created during the summit collapse. Caldera uplift was evident by April 2019, indicating that the magma volume had reached a point where pressurization could be sustained. Modeled gravity change suggests a maximum magma storage rate at Kīlauea's summit during November 2018 to March 2019 that is much less than the pre‐2018 magma supply rate to the volcano.
No Cookie for Climate Change
Authors: Voigt A. , Albern N.
Published: December 2019

Climate change leads to changes in cloud‐radiative heating, which previous work showed have a substantial impact on the response of the atmospheric circulation to climate change. We here compare to what extent this cloud‐radiative impact in models can be diagnosed by the locking method and the Cookie method. We show that the locking method reliably diagnoses the cloud‐radiative impact. In contrast, the Cookie method, which is easier to use and valuable for studying how the presence of clouds affects the present‐day circulation, is inadequate in the context of climate change. It misdiagnoses the cloud‐radiative impact and misses robust aspects of it, including the poleward circulation expansion. We argue that this is related to strong changes in the control climate and water vapor that arise from making clouds transparent to radiation. Our results highlight the need for dedicated locking simulations in the context of climate change.
Physics‐Constrained Machine Learning of Evapotranspiration
Authors: Zhao Wen Li , Gentine Pierre , Reichstein Markus , Zhang Yao , Zhou Sha , Wen Yeqiang , Lin Changjie , Li Xi , Qiu Guo Yu
Published: December 2019

Estimating ecosystem evapotranspiration (ET) is important to understanding the global water cycle and to study land‐atmosphere interactions. We developed a physics constrained machine learning (ML) model (hybrid model) to estimate latent heat flux (LE), which conserves the surface energy budget. By comparing model predictions with observations at 82 eddy covariance tower sites, our hybrid model shows similar performance to the pure ML model in terms of mean metrics (e.g., mean absolute percent errors) but, importantly, the hybrid model conserves the surface energy balance, while the pure ML model does not. A second key result is that the hybrid model extrapolates much better than the pure ML model, emphasizing the benefits of combining physics with ML for increased generalizations. The hybrid model allows inferring the structural dependence of ET and surface resistance (rs), and we find that vegetation height and soil moisture are the main regulators of ET and rs.
Heterogeneous Permeability Changes along a Fault Zone Caused by the Xingwen M5.7 Earthquake in SW China
Authors: Sun Xiaolong , Xiang Yang
Published: December 2019

Earthquakes can change permeability. Continuous monitoring of the response of water level to solid Earth tides or changes in barometric pressure provides an opportunity to document how earthquakes influence permeability. Here we document spatial variations in changes in a fault zone in SW China. The response of the water level to barometric pressure and the Earth tide in four observation wells was used to calculate the relative changes in permeability at different locations on the fault before and after the Xingwen M5.7 earthquake. The results revealed that the earthquake resulted in a spatial heterogeneity in permeability changes along the Huarongshan fault. Moreover, permeability changes in the horizontal and vertical directions differed from one another at the same well location; that is, there was anisotropy at each location. These findings will help to enhance the understanding of earthquake‐induced changes of permeable fault structure and fault segment deformation.
A Comparative Study of Typhoon Hato (2017) and Typhoon Mangkhut (2018)—Their Impacts on Coastal Inundation in Macau
Authors: Yang Jie , Li Linlin , Zhao Kuifeng , Wang Peitao , Wang Dong , Sou In Mei , Yang Zhengtong , Hu Jie , Tang Xiaochun , Mok Kai Meng , Liu Philip Li‐Fan
Published: December 2019

Typhoons Hato (2017) and Typhoon Mangkhut (2018) struck the Pearl River Delta, China, in two consecutive years, causing intense flooding and severe damage along the coast, especially in Macau. These two typhoons are extreme events because of their record‐breaking storm tides, and they are typical typhoons in terms of their track forward directions, which affect the coast of Guangdong Province, China. This paper analyzes and compares the physical processes of these two major typhoons. We first report the results of our posttyphoon surveys in Macau and the constructed inundation maps for both typhoon events. The inundation maps in conjunction with measured wind, atmospheric pressure, and wave data are used to validate a package of numerical models that simulate fully coupled tide‐surge‐wave fields during a typhoon. We quantify storm surges and wave heights in the Pearl River Delta. The surge around Macau was mainly affected by wind, while atmosphere pressure and ocean waves played a secondary role. In additional to inundation depth, we also investigate inundation durations and flow velocities. Typhoon Mangkhut made its landfall at much lower tidal level than that of Typhoon Hato. However, Typhoon Mangkhut generated much larger storm surge with larger affected areas and significantly longer inundation durations. We attribute the causes mainly to Typhoon Mangkhut's storm size, which was almost three times larger than that of Typhoon Hato.
Time‐Varying Emulator for Short and Long‐Term Analysis of Coastal Flood Hazard Potential
Authors: Anderson D. , Rueda A. , Cagigal L. , Antolinez J. A. A. , Mendez F. J. , Ruggiero P.
Published: December 2019

Rising seas coupled with ever increasing coastal populations present the potential for significant social and economic loss in the 21st century. Relatively short records of the full multidimensional space contributing to total water level coastal flooding events (astronomic tides, sea level anomalies, storm surges, wave run‐up, etc.) result in historical observations of only a small fraction of the possible range of conditions that could produce severe flooding. The Time‐varying Emulator for Short‐ and Long‐Term analysis of coastal flood hazard potential is presented here as a methodology capable of producing new iterations of the sea‐state parameters associated with the present‐day Pacific Ocean climate to simulate many synthetic extreme compound events. The emulator utilizes weather typing of fundamental climate drivers (sea surface temperatures, sea level pressures, etc.) to reduce complexity and produces new daily synoptic weather chronologies with an auto‐regressive logistic model accounting for conditional dependencies on the El Niño Southern Oscillation, the Madden‐Julian Oscillation, seasonality, and the prior two days of weather progression. Joint probabilities of sea‐state parameters unique to simulated weather patterns are used to create new time series of the hypothetical components contributing to synthetic total water levels (swells from multiple directions coupled with water levels due to wind setup, temperature anomalies, and tides). The Time‐varying Emulator for Short‐ and Long‐Term analysis of coastal flood hazard potential reveals the importance of considering the multivariate nature of extreme coastal flooding, while progressing the ability to incorporate large‐scale climate variability into site specific studies assessing hazards within the context of predicted climate change in the 21st century.
Deoxygenation and Its Controls in a Semienclosed Shelf Ecosystem, Northern Yellow Sea
Authors: Wei Qinsheng , Yao Qingzhen , Wang Baodong , Xue Liang , Fu Mingzhu , Sun Junchuan , Liu Xuehai , Yu Zhigang
Published: December 2019

Deoxygenation is a global problem in open oceans and coastal regions and has led to the expansion of oxygen minimum zones and coastal hypoxia. Here, using time series observations in the northern Yellow Sea, we illustrate the seasonality of deoxygenation and associated mechanisms in this semienclosed shelf ecosystem and explore the linkage of dissolved oxygen (DO) declines with seawater warming and anthropogenic eutrophication. Our results show that the DO concentration displayed a decreasing trend in winter, with rates of ~0.76 and ~0.78 μmol kg−1 yr−1 in the surface and bottom waters, respectively. The rapid decline in DO was also observed in the bottom water in summer, with a decreasing rate of ~1.43 μmol kg−1 yr−1. In winter, when the water column is vertically homogeneous, the near saturation of DO indicates that physical mixing overwhelmed biological activities, and the estimated results and a linear correlation between DO concentration and temperature suggest that ocean warming is the most plausible driver of deoxygenation in this region in winter. In the stratified water column during summer, increased nutrient availability at the surface and consequently enhanced productivity are responsible for the drawdown of DO in the bottom layer, and the stoichiometric pattern between DO and nitrate also suggests a cascading linkage between the exacerbation of eutrophic conditions and bottom deoxygenation. Our results provide strong evidence that a rapid, semienclosed shelf‐scale decline in DO is underway and highlight the necessity of nutrient reduction strategies in the future.
Do Strong Winds Impact Water Mass, Nutrient, and Phytoplankton Distributions in the Ice‐Free Canada Basin in the Fall?
Authors: Nishino Shigeto , Kawaguchi Yusuke , Inoue Jun , Yamamoto‐Kawai Michiyo , Aoyama Michio , Harada Naomi , Kikuchi Takashi
Published: December 2019

In general, strong wind events can enhance ocean turbulent mixing, followed by episodic nutrient supply to the euphotic zone and phytoplankton blooms. However, it is unclear whether such responses to strong winds occur in the ice‐free Canada Basin, where the seasonal pycnocline is strong and the nutricline is deep. In the present study, we monitored a fixed‐point observation (FPO) station in the Canada Basin for about 3 weeks in the fall of 2014 to examine the oceanic and biological responses to strong winds. At the FPO site, oceanic microstructure measurements, hydrographic surveys, and water sampling were performed with high temporal resolution, recording internal wave propagation, eddy passage, and water mass changes. Strong winds and internal wave propagation significantly enhanced the mixing above and at the seasonal pycnocline, but their effects were diminished at the nutricline, which was much deeper than the seasonal pycnocline. Therefore, wind‐induced mixing did not increase the upward nutrient supply from the nutricline and did not impact phytoplankton (chlorophyll a) distribution in the surface layer of the FPO site. The temporal evolution of the chlorophyll a concentration was most closely related to water mass changes. We also observed prominent subsurface chlorophyll a maxima with abundant large‐sized phytoplankton that were likely carried by warm‐core eddies to the FPO site. Phytoplankton biomass may have been sustained by the high concentration of ammonium within the eddy and ammonium regeneration at the seasonal pycnocline, where particulate organic matter likely accumulated.
Climate Forcing and Trends of Organic Aerosols in the Community Earth System Model (CESM2)
Authors: Tilmes S. , Hodzic A. , Emmons L. K. , Mills M. J. , Gettelman A. , Kinnison D. E. , Park M. , Lamarque J.‐F. , Vitt F. , Shrivastava M. , Campuzano‐Jost P. , Jimenez J. L. , Liu X.
Published: December 2019

The Community Earth System Model version 2 (CESM2) includes three main atmospheric configurations: the Community Atmosphere Model version 6 (CAM6) with simplified chemistry and a simplified organic aerosol (OA) scheme, CAM6 with comprehensive tropospheric and stratospheric chemistry representation (CAM6‐chem), and the Whole Atmosphere Community Climate Model version 6 (WACCM6). Both, CAM6‐chem and WACCM6 include a more comprehensive secondary organic aerosols (SOA) approach using the Volatility Basis Set (VBS) scheme and prognostic stratospheric aerosols. This paper describes the different OA schemes available in the different atmospheric configurations of CESM2 and discusses differences in aerosol burden and resulting climate forcings. Derived OA burden and trends differ due to differences in OA formation using the different approaches. Regional differences in Aerosol Optical Depth with larger values using the comprehensive approach occur over SOA source regions. Stronger increasing SOA trends between 1960 and 2015 in WACCM6 compared to CAM6 are due to increasing biogenic emissions aligned with increasing surface temperatures. Using the comprehensive SOA approach further leads to improved comparisons to aircraft observations and SOA formation of ≈143 Tg/yr. We further use WACCM6 to identify source contributions of OA from biogenic, fossil fuel, and biomass burning emissions, to quantify SOA amounts and trends from these sources. Increasing SOA trends between 1960 and 2015 are the result of increasing biogenic emissions aligned with increasing surface temperatures. Biogenic emissions are at least two thirds of the total SOA burden. In addition, SOA source contributions from fossil fuel emissions become more important, with largest values over Southeast Asia. The estimated total anthropogenic forcing of OA in WACCM6 for 1995–2010 conditions is −0.43 W/m2, mostly from the aerosol direct effect.
Reconstructing 800 Years of Carbonate Ion Concentration in the Cariaco Basin Using the Area Density of Planktonic Foraminifera Shells
Authors: Davis A. N. , Davis C. V. , Thunell R. C. , Osborne E. B. , Black D. E. , Benitez‐Nelson C. R.
Published: December 2019

Anthropogenically mediated ocean acidification (OA) has negative impacts on many marine organisms, especially calcifiers. However, systematic measurements of OA have only been made over the past four decades. In order to improve future predictions and understand how ongoing OA compares to natural variability on longer timescales, it is critical to extend records beyond observational time series. In the Cariaco Basin, located in the tropical Atlantic, near‐surface dissolved inorganic carbon reflects atmospheric carbon dioxide concentrations (CO2) since the Industrial Revolution, making it an ideal site for examining longer‐term variability. We extend the record of Cariaco Basin near‐surface [CO32−] back to 1240 CE, using the area density (shell weight (μg)/shell area (μm2)) of the planktonic foraminifer Globigerinoides ruber (pink). Multidecadal variability is observed throughout the record. Since the Industrial Revolution (1760–2007 CE), [CO32−] has declined by 0.22 μmol kg−1 year−1, in agreement with the magnitude and direction of change captured in the shorter instrumental time series. During the Little Ice Age (1500–1760 CE), a period marked by regional drought, substantial variability but no long‐term trend is observed, while a decrease in [CO32−] of 0.11 μmol kg−1 y−1 occurs at the end of the Medieval Climate Anomaly (MCA) (1240 – 1500 CE). Both the MCA and Little Ice Age contain substantial natural variability in near surface [CO32−] that we attribute to changes in regional upwelling and atmospheric CO2. However, the decline in [CO32−] occurring in the Post‐Industrial Period is anomalous against a backdrop of 800 years of natural variability, reflecting OA associated with anthropogenic increases in atmospheric CO2.