bluuebunny/crossref_metadata_2025 huggingface dataset:
Metal composite T-junction terminals for MW-class aerospace electric power distribution
Authors: Kovacs C J , Haugan T J , Sumption M D
Published: July 2021

There is a recent surge in activity to develop high power electric (or hybrid electric) aircraft. Part of this development effort is the creation of lightweight and small volume high-performance motors and airborne power transmission cables. As part of the power transmission of a distributed propulsion aircraft will be T-terminals to extract power to individual motors from a “main” power cable. In this research, a standard pressed plate high purity Cu T-terminal, with cylindrical high-temperature superconducting cables (main cable current of 20 kA, branch cable current of 2.5 kA), were investigated using Multiphysics simulations. Then, a more geometrically optimized high purity Al-Cu composite T-terminal was simulated under similar conditions. Discussed are the influence of T-junction geometry, operating temperature (30 to 50 K), contact resistance, and magnetoresistance on joule losses of terminals with different masses. It is shown the Al-Cu terminal can greatly reduce joule losses/mass of the T-terminal while also having an intrinsic clamping force from thermal expansion of the Al shell of the composite structure.
Are cleaner cooking solutions clean enough? A systematic review and meta-analysis of particulate and carbon monoxide concentrations and exposures
Authors: Pope Daniel , Johnson Michael , Fleeman Nigel , Jagoe Kirstie , Duarte Rui , Maden Michelle , Ludolph Ramona , Bruce Nigel , Shupler Matthew , Adair-Rohani Heather , Lewis Jessica
Published: July 2021

Globally, approximately 3 billion primarily cook using inefficient and poorly vented combustion devices, leading to unsafe levels of household air pollution (HAP) in and around the home. Such exposures contribute to nearly 4 million deaths annually (WHO 2018a, 2018b ). Characterizing the effectiveness of interventions for reducing HAP concentration and exposure is critical for informing policy and programmatic decision-making on which cooking solutions yield the greatest health benefits. This review synthesizes evidence of in-field measurements from four cleaner cooking technologies and three clean fuels, using field studies aimed at reducing HAP concentration and personal exposure to health damaging pollutants (particulate matter (PM2.5) and carbon monoxide (CO)). Fifty studies from Africa, Asia, South and Latin America, provided 168 estimates synthesized through meta-analysis. For PM2.5 kitchen concentrations, burning biomass more cleanly through improved combustion stoves (ICS) with (n = 29; 63% reduction) or without (n = 12; 52%) venting (through flue or chimney) and through forced-draft combustion (n = 9; 50%) was less effective than cooking with clean fuels including ethanol (n = 4; 83%), liquefied petroleum gas (LPG) (n = 11; 83%) and electricity (n = 6; 86%). Only studies of clean fuels consistently achieved post-intervention kitchen PM2.5 levels at or below the health-based WHO interim target level 1 (WHO-IT1) of 35 μg m−3. None of the advanced combustion stoves (gasifiers) achieved WHO-IT1, although no evidence was available for pellet fuelled stoves. For personal exposure to PM2.5, none of the ICS (n = 11) were close to WHO-IT1 whereas 75% (n = 6 of 8) of LPG interventions were at or below WHO-IT1. Similar patterns were observed for CO, although most post-intervention levels achieved the WHO 24 h guideline level. While clean cooking fuel interventions (LPG, electric) significantly reduce kitchen concentrations and personal exposure to PM2.5 in household settings, stove stacking and background levels of ambient air pollution, have likely prevented most clean fuel interventions from approaching WHO-IT1. In order to maximize health gains, a wholistic approach jointly targeting ambient and HAP should be followed in lower-and-middle income countries.
Fair distributions of carbon dioxide removal obligations and implications for effective national net-zero targets
Authors: Lee Kaylin , Fyson Claire , Schleussner Carl-Friedrich
Published: July 2021

Achieving net-zero emissions at the global level, as required to limit warming to 1.5 °C, means both rapid emissions reductions across all sectors as well as a scaling-up of carbon dioxide removal (CDR). As a growing number of countries bring forward national net-zero targets, the questions of how much CDR each nation holds responsibility for, whether CDR transfers should be possible under the Paris Agreement market mechanisms, and how this might affect the years in which different countries should achieve net-zero, become increasingly important. Here we show that, depending on the normative assumptions underlying a CDR burden-sharing system, the adjusted net-zero date for big emitting countries could shift forward by up to 15 years (EU, based on gross domestic product) to 35 years (Russia, based on cumulative per capita emissions) compared with what is modeled domestically in global least-cost scenarios. This illustrates a challenge of using least-cost model scenarios as a basis for setting and evaluating net-zero targets. We also evaluate the potential risk of carbon loss associated with CDR transfers of such a magnitude, and consider how a discount factor could help address carbon loss risks and contribute to overall mitigation. Our results highlight the need for clear guidelines to ensure that international CDR transfers do not obscure urgently-needed domestic emission reductions efforts by big emitters, while promoting a fair and equitable distribution of the CDR burden inflicted by insufficient near-term mitigation. We find a separate mechanism or accounting for CDR obligations to be the most promising avenue to deliver on these objectives.
Assessing Customer Satisfaction of Airport Train Service: An Application of the Kano Model
Authors: Waly G Z , Miranda I E , Adelia D R , Oktavia W D , Aulia M A , Wibowo A T , Ulkhaq M M
Published: July 2021

Every service firm must find ways to attract new customers, retain existing customers, and remain competitive and profitable. As competition increases, pursuing customer satisfaction becomes more important in this particular global market competitiveness. Previously, traditional methods believe that customer satisfaction and quality attributes have a linear relationship. In other words, customers might feel satisfied when certain quality attribute can be provided by the service provider; yet they might not feel satisfied when the quality attribute is missing. Nevertheless, this relationship is not that linearly simple. In some quality attributes, indeed an improvement in performance of the service attribute can significantly improve customer satisfaction; while on the other case, the customers might still accept the absence of a quality attribute without being dissatisfied. This phenomenon has been identified by the Kano model which uses a different approach to treat the relationship between customer satisfaction and quality attributes as two-dimensional terms. This research aims to evaluate customer satisfaction of airport train service by utilizing the Kano model. Eighteen attributes were employed in a case study that exhibited the application of the Kano model to assess customer satisfaction. By implementing the Kano model, it is intended to provide a strategy for the service provider to improve customer satisfaction.
Spacecraft in ‘warp bubble’ could travel faster than light
Authors: Skuse Benjamin
Published: July 2021

Special relativity famously dictates that no known object can travel faster than the speed of light in a vacuum – making it unlikely that humans will ever send spacecraft to explore beyond our local area of the Milky Way. However, new research by Erik Lentz at the University of Göttingen suggests there could be a way beyond this limit.
Government scientific workforce ‘dangerously diminished’
Authors: Gwynne Peter
Published: July 2021

Recent staff reductions at US government agencies have been exacerbated by the Trump administration’s “open hostility towards federal scientists and the federal workforce”. That is according to a report by members of the Democratic majority on the House of Representatives Science Committee
Artificial intelligence
Authors: Commissariat Tushna
Published: July 2021

Explore the good, the bad and the ugly of the symbiotic relationship between AI and physics in this special issue
Climate basics
Authors: Dryburgh Peter
Published: July 2021

On the need for articles that explain the basics of climate modelling and how it predicts global warming, in addition to the many articles that talk about the predictions themselves.
The science in science fiction
Authors: Randall Ian
Published: July 2021

Ian Randall reviews Science Fiction by Sherryl Vint
Life satisfaction among older adults with impairment in activities of daily living
Authors: Boccaccio Dominic E , Cenzer Irena , Covinsky Kenneth E
Published: July 2021

Background

Many older adults experience decline in function, but maintain high levels of life satisfaction. The factors associated with high life satisfaction among those with functional impairment are not well understood.

Objective

Examine the proportion of older adults with functional impairment reporting high life satisfaction and the predictors of high life satisfaction.

Design

Cross-sectional cohort study.

Setting

Health and Retirement Study.

Subjects

A total of 7,287 community-dwelling participants, 65 years or older, who completed the leave-behind questionnaire in 2014 or 2016.

Methods

The main predictor was having difficulty or needing help in performing Activities of Daily Living (ADL). The primary outcome was reporting high life satisfaction, defined using a three-item Diener scale. Significant factors were identified using modified Poisson regression models adjusted for demographic characteristics.

Results

Those with no ADL impairment were more likely to report high levels of life satisfaction than those with ADL difficulty or ADL dependence (54.4 vs 38.6 vs 27.6%, P < 0.001). Among those with ADL dependence, we identified several factors associated with high life satisfaction, including: not being lonely (38.2 vs 23.2%, ARR = 1.6 (1.2, 2.2)), satisfied with family life (35.1 vs 12.8%, ARR = 2.7 (1.6, 4.4)), and satisfied with financial situation (40.8 vs 16.6%, ARR = 2.5 (1.8, 3.6)). Similar associations were present among those with ADL difficulty.

Conclusions

A substantial proportion of older adults with ADL impairment report high life satisfaction, and it is associated with social and economic well-being. Understanding the factors associated with high life satisfaction can lead to clinical practices and policy guidelines that promote life satisfaction in older adults.
Performance Characteristics of DOAC-Remove for Neutralization of the Effects of Apixaban and Rivaroxaban in Lupus Anticoagulant Assays
Authors: Skaugen John M , Sayre Christine , Hassett Andrea Cortese , Chibisov Irina , Bontempo Franklin , Meyer Michael P , Seheult Jansen N
Published: July 2021

Objectives

This study established the performance characteristics of DOAC-Remove for neutralization of the effects of rivaroxaban and apixaban in lupus anticoagulant (LAC) testing.

Methods

Normal donor, LAC control, and patient samples were spiked with rivaroxaban or apixaban to simulate their effects on the dilute Russell’s viper venom time (dRVVT), activated partial thromboplastin time (APTT), and dilute prothrombin time (dPT). Anti-Xa activity was measured after spiking and after DOAC-Remove neutralization. Accuracy, complex precision, and reference interval verification were evaluated.

Results

DOAC-Remove neutralized rivaroxaban and apixaban concentrations as high as 415 ng/mL and 333 ng/mL, respectively. Percentage positive and negative agreement between the baseline and postneutralization interpretations were 75% or higher for the dRVVT and APTT methods but not for the dPT method. Coefficients of variation (CVs) were 10% or less for all assays except the Staclot-LA delta, which had a standard deviation of 2.5 seconds or CV of 25% or less depending on the level. The laboratory’s reference intervals were verified for the dRVVT and APTT assays after DOAC-Remove treatment but not for the dPT assays.

Conclusions

DOAC-Remove appears to have acceptable performance characteristics for neutralizing the effects of rivaroxaban and apixaban in the dRVVT and APTT methods but not in the dPT method.
Dimensional Analysis of Atypical Functional Connectivity of Major Depression Disorder and Bipolar Disorder
Authors: Chen Heng , Lu Fengmei , Guo Xiaonan , Pang Yajing , He Changchun , Han Shaoqiang , Duan Xujun , Chen Huafu
Published: July 2021

Literatures have reported considerable heterogeneity with atypical functional connectivity (FC) pattern of psychiatric disorders. However, traditional statistical methods are hard to explore this heterogeneity pattern. We proposed a “brain dimension” method to describe the atypical FC patterns of major depressive disorder and bipolar disorder (BD). The approach was firstly applied to a simulation dataset. It was then utilized to a real resting-state functional magnetic resonance imaging dataset of 47 individuals with major depressive disorder, 32 individuals with BD, and 52 well matched health controls. Our method showed a better ability to extract the FC dimensions than traditional methods. The results of the real dataset revealed atypical FC dimensions for major depressive disorder and BD. Especially, an atypical FC dimension which exhibited decreased FC strength of thalamus and basal ganglia was found with higher severity level of individuals with BD than the ones with major depressive disorder. This study provided a novel “brain dimension” method to view the atypical FC patterns of major depressive disorder and BD and revealed shared and specific atypical FC patterns between major depressive disorder and BD.
Coronary embolism due to possible thrombosis of prosthetic aortic valve - the role of optical coherence tomography: case report
Authors: Kavaliauskaite Raminta , Otsuka Tatsuhiko , Ueki Yasushi , Räber Lorenz
Published: July 2021

Background

Coronary embolism is an important non-atherosclerotic cause of acute myocardial infarction (AMI) that requires an individualized diagnostic and therapeutic approach. Although certain angiographic criteria exist that render an embolic origin likely, uncertainty remains. Optical coherence tomography (OCT) is a high-resolution intracoronary imaging technology that enables visualization of thrombus and the underlying coronary vessel wall, which may be helpful to distinguish between an atherosclerotic and non-atherosclerotic origin of AMI.

Case summary 

A 50-year-old male was admitted with ongoing chest pain. Eleven years ago, he underwent implantation of a mechanical aortic valve prosthesis due to degenerated bicuspid valve with normal coronaries on preoperative angiography. The electrocardiogram showed anterior ST-segment elevation. Emergent angiography revealed total occlusion of the proximal left anterior descending artery (LAD). Thrombus was aspirated along with administration of intravenous glycoprotein IIbIIIa inhibitor. Except the apical part of the LAD showing distal embolization, coronary flow was completely re-established with no evidence of significant atherosclerosis. Stents were not implanted on the basis of the OCT finding, which demonstrated at the site of occlusion a normal vessel wall without atherosclerosis that could explain an erosion or plaque rupture event. Transoesophageal echocardiography confirmed a floating structure in the left ventricular outflow tract, suggesting that an embolus originating from the prosthetic aortic valve obstructed the LAD. The international normalized ratio 2 days prior to presentation measured 1.9.

Discussion 

This case illustrates the utility of OCT to rule out the atherosclerotic aetiology of myocardial infarction and to avoid unnecessary stenting.
First successful transcatheter valve-in-valve implantation into a failed mechanical prosthetic aortic valve facilitated by fracturing of the leaflets: a case report
Authors: Butter Christian , Kühnel Ralf-Uwe , Hölschermann Frank
Published: July 2021

Background

Degenerated and failed bioprosthetic cardiac valves can safely be treated with transcatheter valve-in-valve implantation in patients at high risk for reoperation. So far, non-functional mechanical valves must be treated with a surgical redo. Breaking the carbon leaflets before implanting a transcatheter valve into the remaining ring has never been described before.

Case summary

Here, we present the case of a 65-year-old male patient with severe heart failure, poor left ventricular function based on a fully immobile disc of his mechanical bileaflet aortic valve implanted 7 years ago. After the heart team declined to reoperate the patient due to his extremely high risk, we considered a transcatheter valve-in-valve implantation as the ultimate treatment approach. After successful interventional cracking of the leaflets in vitro, this approach, together with implanting a balloon-expandable transcatheter aortic valve replacement (TAVR) into the remaining ring, was performed under cerebral protection. The intervention resulted in a fully functional TAVR, improvement of heart function, and early discharge from the hospital.

Discussion

This case demonstrates the possibility to implant a transcatheter valve successfully into a non-functional mechanical bileaflet aortic prosthesis after fracturing the carbon discs while the brain is protected by a filter system. Critical steps of the procedure were identified. This new therapeutic approach might be offered to a limited patient cohort who is not eligible for a surgical redo.
Post-pubertal effects of the Alt-RAMEC/FM and RME/FM protocols for the early treatment of Class III malocclusion: a retrospective controlled study
Authors: Masucci Caterina , Franchi Lorenzo , Franceschi Debora , Pierleoni Felicita , Giuntini Veronica
Published: July 2021

Objective

To assess the stability of the effects of the modified Alt-RAMEC and facial mask (FM) protocol at a post-pubertal observation.

Methods

Twenty-one Class III patients (11 males and 10 females, 6.5 ± 0.7 years) treated consecutively with the Alt-RAMEC/FM approach and presenting with lateral cephalograms taken before treatment (T1), after treatment (T2), and at post-pubertal observations (T3) were compared with 22 Class III patients (9 males and 13 females, 6.9 ± 1.2 years) treated with the rapid maxillary expansion (RME) and FM protocol and with 15 Class III untreated subjects (7 males and 8 females, 6.2 ± 2.2 years). At T3, all patients showed a post-pubertal skeletal maturation stage (CS4–CS6). Descriptive statistics and statistical comparisons between the three groups at T1 and for the T3–T1, T2–T1, and T3–T2 changes were assessed by means of the ANOVA or Kruskal–Wallis test.

Results

During the overall observation period, Alt-RAMEC/FM and RME/FM protocols produced statistically significant favourable effects when compared with the Control group (ANB + 2.8° and +2.2°, respectively; Wits appraisal +4.4 mm and +2.7 mm, respectively). No statistically significant differences were found between the outcomes of the Alt-RAMEC/FM and RME/FM protocols neither at the post-pubertal or short-term observations.

Limitations

Retrospective study and the comparison with an historical control sample of subjects with untreated Class III malocclusion.

Conclusions

The Alt-RAMEC/FM protocol cannot be recommended as the approach of choice for the therapy of Class III dentoskeletal disharmony in very young subjects compared to the conventional RME/FM protocol.
The biological sex lens on early orthopaedic treatment duration and outcomes in Class III orthodontic patients: a systematic review
Authors: Arqub Sarah Abu , Al-Zubi Khadijeh , Iverson Marissa G , Ioannidou Effie , Uribe Flavio
Published: July 2021

Background

Treatment outcomes for Class III orthopaedic treatment are highly unpredictable and dependent on the timing of interception, age, and biological sex.

Objective

This systematic review aimed to assess the effects of sex dimorphism on outcomes and duration of orthopaedic treatment for Class III malocclusion in young children.

Search methods

Unrestricted search in six electronic databases until May 2021 was conducted. Supplemented by search in resources for published, unpublished literature, and ongoing trials.

Selection criteria

Randomized and non-randomized controlled trials reporting the use of Class III growth modification appliances, with baseline and outcome data for both sexes, were included.

Data collection and analysis

Study selection and data extraction were performed blindly and in duplicate by two reviewers. ROBINS-I, Cochrane Risk of Bias, and GRADE tools were used for certainty assessment.

Results

A total of 2429 records were screened. Four trials fulfilled the inclusion criteria, one was a randomized clinical trial (RCT) comparing facemask and facemask with mini-screw. Two clinical trials evaluated the effects of facemask appliance, one had a control group, another was prospective non-controlled. One compared the effects of the maxillary protraction bow appliance to a no treatment control. Two of the clinical trials were appraised as low and one was appraised as high risk of bias. The overall certainty of the available evidence was assessed as moderate. There was significant clinical heterogeneity in terms of methodology, type of intervention, and the measured outcomes, precluding a meta-analysis.

Conclusions

Minimal variations in sagittal, vertical, and dentoalveolar post-treatment cephalometric changes were reported between sexes. The available evidence is unclear to support these variations. Long-term-powered RCTs assessing cephalometric outcomes between sexes until the end of growth spurt and without pooling are not available, therefore, much needed.

Registration

PROSPERO database number CRD42020185797.
Effect of remote monitoring on clinical outcomes in European heart failure patients with an implantable cardioverter-defibrillator: secondary results of the REMOTE-CIED randomized trial
Authors: Chiu Cheyenne S L , Timmermans Ivy , Versteeg Henneke , Zitron Edgar , Mabo Philippe , Pedersen Susanne S , Meine Mathias ,   for the REMOTE-CIED Trial Investigators
Published: July 2021

Aims

Remote patient monitoring (RPM) systems offer a promising alternative to conventional In-Clinic check-ups, hereby reducing unnecessary clinic visits. Especially with the rise of the COVID-19 pandemic, this reduction is of paramount importance. Regarding the association between RPM and clinical outcomes, findings of previous studies have been inconsistent. The aim of this study is to elucidate the effect of partly substituting In-Clinic visits by RPM on clinical outcomes in implantable cardioverter-defibrillator (ICD) patients.

Methods and results

The study included 595 heart failure patients (LVEF ≤35%; NYHA Class II/III) implanted with an ICD compatible with the Boston Scientific LATITUDE™ system. Participants were randomized to RPM plus an annual In-Clinic visit or 3–6 months In-Clinic check-ups alone. The investigated endpoints after 2 years of follow-up included a composite of all-cause mortality and cardiac hospitalization, mortality and cardiac hospitalization as independent endpoints and ICD therapy. The incidence of mortality and hospitalization did not differ significantly as independent, nor as composite endpoint between the RPM and In-Clinic group (all Ps <0.05). The results were similar regarding ICD therapy, except for appropriate ICD therapy (odds ratio 0.50; 95% confidence interval 0.26–0.98; P = 0.04). Exploratory subgroup analyses indicated that the effect of RPM differs between patients with specific characteristics, i.e. ≥60 years and permanent atrial fibrillation (all Ps < 0.05).

Conclusion

RPM is non-inferior to conventional In-Clinic visits regarding clinical outcomes. Routine In-Clinic follow-up may partly be substituted by RPM without jeopardizing safety and efficiency, and thus reducing unnecessary In-Clinic visits.

ClinicalTrials.gov identifier

NCT01691586.
Simultaneous gravity measurements using two superconducting gravimeters to observe temporal gravity changes below the nm s−2 level: ocean tide loading differences at different distances from the coast
Authors: Goto Hiroki , Sugihara Mituhiko , Nishi Yuji , Ikeda Hiroshi
Published: July 2021

Gravity monitoring might require observation of temporal changes of gravity below the nanometre per second squared (nm s−2) level, which can be achieved by precise isolation of the signal of interest from all other disturbing effects. One method of signal isolation is elimination of disturbing effects by taking the difference between gravity changes measured simultaneously using two gravimeters installed close together. Herein, we describe differences in temporal gravity changes below the nm s−2 level in the tidal frequency bands as observed through simultaneous measurements taken with three superconducting gravimeters (SGs) located 80, 93 and 94 m from the coastline in Tomakomai, Hokkaido, northern Japan. Those changes are consistent with differences in ocean tide loading effects on gravity at the SG locations computed using the software package GOTIC2, which uses a highly accurate land–sea boundary and ocean tide model near our site. The observed ocean tide loading differences were found to result from Newtonian attraction of the ocean tide mass within an angular distance of 0.003° from the SG locations. This result suggests that coastal observations of differential tidal gravity variations at different distances from the coast help to validate ocean tide loading computation models in the immediate vicinity of the SG stations. This method enables observation of non-periodic gravity changes occurring below the nm s−2 level over a few hours. Its salient benefit is that rapid and simple observation can be achieved without long-term continuous measurements, which is necessary for observing that level of gravity change with only one SG.
Back-propagating rupture evolution within a curved slab during the 2019Mw 8.0 Peru intraslab earthquake
Authors: Hu Yaping , Yagi Yuji , Okuwaki Ryo , Shimizu Kousuke
Published: July 2021

The 26 May 2019 MW 8.0 Peru intraslab earthquake ruptured the subducting Nazca Plate where the dip angle of the slab increases sharply and the strike angle rotates clockwise from the epicentre to north. To obtain a detailed seismic source model of the 2019 Peru earthquake, including not only the rupture evolution but also the spatiotemporal distribution of focal mechanisms, we performed comprehensive seismic waveform analyses using both a newly developed flexible finite-fault teleseismic waveform inversion method and a back-projection method. The source model revealed a complex rupture process involving a back-propagating rupture. The initial rupture propagated downdip from the hypocentre, then unilaterally northward along the strike of the slab. Following a large slip occurring ∼50–100 km north of the hypocentre, the rupture propagated bilaterally both further northward and back southward. The spatial distribution of focal mechanisms shows that the direction of T-axis azimuth gradually rotated clockwise from the epicentre northward, corresponding to the clockwise rotation of the strike of the subducting Nazca Plate, and the large-slip area corresponds to the high-curvature area of the slab iso-depth lines. Our results show that the complex rupture process, including the focal-mechanism transition, of the Peru earthquake was related to the slab geometry of the subducting Nazca Plate.
Influential parameters on 3-D synthetic ground motions in a sedimentary basin derived from global sensitivity analysis
Authors: De Martin F , Chaljub E , Thierry P , Sochala P , Dupros F , Maufroy E , Hadri B , Benaichouche A , Hollender F
Published: July 2021

Which physical parameters are the most influential when predicting earthquake ground motions in a 3-D sedimentary basin? We answer quantitatively by doing a global sensitivity analysis of two quantities of interest: the peak ground motions (PGMs) and a time–frequency representation (the S transform) of ground motions resulting from the synthetic anelastic responses of the EUROSEISTEST. This domain of interest is modeled by two layers with uncertain depth-dependent mechanical properties and is illuminated by a plane S-wave propagating vertically upward in an uncertain homogeneous elastic bedrock. The global sensitivity analysis is conducted on 800+ physics-based simulations of the EUROSEISTEST requiring 8+ million core-hours (i.e. ≈ 900 yr of mono-core computation). The analysis of the PGMs at the free surface displays the spatial influence of the uncertain input parameters over the entire basin scale, while the analysis of the time–frequency representation shows their influence at a specific location inside the basin. The global sensitivity analysis done on the PGMs points out that their most influential parameter in the middle of the basin is the quality factor QS (it controls up to 80 per cent of the PGMs in certain locations where the sediments thickness is larger than 200 m). On the other hand, the geological layering configuration (here represented by the depth of a geological interface controlling the geological layering) strongly influences the PGMs close to the basin edges, up to 90 per cent. We also found that the shear wave velocity at the free surface of the basin and the one of the bedrock underlying the basin are to be considered on an equal footing, both influencing the PGMs in the middle of the basin and close to its edges. We highlight that the bedrock to basin amplification of the PGMs shows a clear increase with respect to the thickness of the sediments, but this amplification saturates from 200 m of sediments around the value of three and is frequency dependent. This PGMs amplification starts from about one tenth of the mean S-wavelength propagating in the basin. The global sensitivity analysis done on the S transform of the ground motions shows that (i) the own effect of the parameters fully controls the first S-wave train and mostly controls the direct arrival of the basin-induced surfaces waves, (ii) the quality factor QS controls 40–60 per cent of the decay of amplitude of coda waves, the remaining part being mainly controlled by interaction effects due to the coupling effect of several parameters and (iii) the interaction effects between the parameters increases with time, suggesting under the hypotheses of our study that the own effects control the ballistic wave propagation while the interaction effects control the diffusive wave propagation.
Optimal inspection policy for a second-hand product with a two-dimensional warranty
Authors: Heydari Majeed
Published: July 2021

This paper studies the situation in which a manufacturer acts as a dealer and buys a second-hand product from one customer and sells it with a two-dimensional warranty to another customer. The manufacturer plans to inspect the product during the warranty period to identify and remove hidden defects and hence prevent failure as well as their corresponding cost. We describe a two-dimensional delay time model in which the customer’s usage rate affects both the time to defect and delay time. This concept is then used to derive a new class of failure models, namely, the two-dimensional and two-stage failure model. The number and time of inspections are determined to minimize the service cost during the warranty period under periodic and sequential inspection policies. Our approach is illustrated using an example from the automobile industry. A sensitivity analysis evaluates the effect of changes in the parameters of the model. Results indicate that the proposed model can aid the decision-making of a manufacturer, particularly in relation to the effect of customers’ usage and the effect of inspection upon the service cost during the warranty period.
On the Asymptotic Behavior of Solutions to the Vlasov–Poisson System
Authors: Ionescu Alexandru D , Pausader Benoit , Wang Xuecheng , Widmayer Klaus
Published: July 2021

We prove small data modified scattering for the Vlasov–Poisson system in dimension $d=3$, using a method inspired from dispersive analysis. In particular, we identify a simple asymptotic dynamics related to the scattering mass.
Liberal Ideology and Foreign Opinion on China
Authors: Chu Jonathan A
Published: July 2021

Why do autocratic powers like China evoke negative attitudes from the citizens of some countries but not from others? Factors like economic and security threat are of course part of the answer, but this study finds that ideational factors exert a distinct effect. Drawing from social theories of the democratic peace and international relations more broadly, it observes that governments and their citizens form communities along ideological lines, which most prominently includes differences in liberal democracy. This argument implies that people within the liberal community tend to view authoritarian powers like China as having a harmful influence on the world. Furthermore, democratic citizens will evaluate China from the standpoint of liberal democratic norms. Because liberal norms are not just about having multiparty, electoral institutions, people's opinions on China could vary even if its single-party political system does not change. Three empirical studies drawing from cross-national observational data, two original survey experiment, and a difference-in-differences analysis of historical polls confirm that liberal democracy affects foreign perceptions about China. The findings advance debates about soft power, democracy and public opinion, and the role of ideology in international society.
ESBL-positive Escherichia coli and Klebsiella pneumoniae isolates from across Canada: CANWARD surveillance study, 2007–18
Authors: Karlowsky James A , Walkty Andrew , Golden Alyssa R , Baxter Melanie R , Denisuik Andrew J , McCracken Melissa , Mulvey Michael R , Adam Heather J , Zhanel George G
Published: July 2021

Objectives

ESBL-producing Escherichia coli and Klebsiella pneumoniae are pathogens of increasing importance in Canada and elsewhere in the world. The purpose of this study was to phenotypically and molecularly characterize ESBL-producing E. coli and K. pneumoniae clinical isolates obtained from patients attending Canadian hospitals over a 12 year period.

Methods

Isolates were collected between January 2007 and December 2018 as part of an ongoing national surveillance study (CANWARD). ESBL production was confirmed using the CLSI (M100) phenotypic method. Susceptibility testing was carried out using custom broth microdilution panels, and all isolates underwent WGS.

Results

In total, 671 E. coli and 141 K. pneumoniae were confirmed to be ESBL producers. The annual proportion of ESBL-producing isolates increased for both E. coli (from 3.3% in 2007 to 11.2% in 2018; P < 0.0001) and K. pneumoniae (from 1.3% in 2007 to 9.3% in 2018; P < 0.0001). The most frequent STs were ST131 for E. coli [62.4% (419/671) of isolates] and ST11 [7.8% (11/141)] and ST147 [7.8% (11/141)] for K. pneumoniae. Overall, 97.2% of ESBL-producing E. coli and K. pneumoniae isolates were MDR. blaCTX-M-15 predominated in both ESBL-producing E. coli (62.3% of isolates) and ESBL-producing K. pneumoniae (48.9% of isolates).

Conclusions

The proportion of ESBL-producing E. coli, especially ST131, and K. pneumoniae, especially ST11 and ST147, in Canada increased significantly from 2007 to 2018. Continued prospective surveillance of these evolving MDR and at times XDR pathogens is imperative.
Arbuscular mycorrhizal fungi enhance the growth of the exotic speciesAmbrosia artemisiifolia
Authors: Kong Lingjie , Chen Xue , Yerger Ellen Heininger , Li Qiao , Chen Fengxin , Xu Haiyun , Zhang Fengjuan
Published: July 2021

Arbuscular mycorrhizal fungi (AMF) can increase host plant nutrient uptake via their mycelium, thus promoting plant growth. AMF have always been associated with successful invasion of most exotic plant species. However, knowledge regarding how AMF affect the success of plant invasion remains limited. Exotic Ambrosia artemisiifolia is an invasive and mycorrhizal plant species. A long-term field experiment was conducted to examine the differences in AMF diversity and composition in the roots of A. artemisiifolia and Setaria viridis subjected to interspecific competition during growth. A greenhouse experiment was also performed to test the effect of Funneliformis mosseae on the growth of these two species. Ambrosia artemisiifolia invasion caused AMF diversity to change in native S. viridis roots. Meanwhile, the relative abundance of F. mosseae was significantly higher in the roots of A. artemisiifolia than in those of S. viridis. The higher AMF colonization rate in the exotic species (A. artemisiifolia) than in the native species (S. viridis) was found in both the field and greenhouse experiments. The greenhouse experiment possibly provided that AMF advantaged to the growth of A. artemisiifolia, by influencing its photosynthetic capacity as well as its phosphorus and potassium absorption. These observations highlight the important relationship of AMF with the successful invasion of A. artemisiifolia.
Small molecule inhibitors of mammalian GSK-3β promote in vitro plant cell reprogramming and somatic embryogenesis in crop and forest species
Authors: Berenguer Eduardo , Carneros Elena , Pérez-Pérez Yolanda , Gil Carmen , Martínez Ana , Testillano Pilar S
Published: July 2021

Plant in vitro regeneration systems, such as somatic embryogenesis, are essential in breeding; they permit propagation of elite genotypes, production of doubled-haploids, and regeneration of whole plants from gene editing or transformation events. However, in many crop and forest species, somatic embryogenesis is highly inefficient. We report a new strategy to improve in vitro embryogenesis using synthetic small molecule inhibitors of mammalian glycogen synthase kinase 3β (GSK-3β), never used in plants. These inhibitors increased in vitro embryo production in three different systems and species, microspore embryogenesis of Brassica napus and Hordeum vulgare, and somatic embryogenesis of Quercus suber. TDZD-8, a representative compound of the molecules tested, inhibited GSK-3 activity in microspore cultures, and increased expression of embryogenesis genes FUS3, LEC2, and AGL15. Plant GSK-3 kinase BIN2 is a master regulator of brassinosteroid (BR) signalling. During microspore embryogenesis, BR biosynthesis and signalling genes CPD, GSK-3-BIN2, BES1, and BZR1 were up-regulated and the BAS1 catabolic gene was repressed, indicating activation of the BR pathway. TDZD-8 increased expression of BR signalling elements, mimicking BR effects. The findings support that the small molecule inhibitors promoted somatic embryogenesis by activating the BR pathway, opening up the way for new strategies using GSK-3β inhibitors that could be extended to other species.
The B-type binaries characterization programme I. Orbital solutions for the 30 Doradus population
Authors: Villaseñor J I , Taylor W D , Evans C J , Ramírez-Agudelo O H , Sana H , Almeida L A , de Mink S E , Dufton P L , Langer N
Published: July 2021

We present results from the B-type binaries characterization (BBC) programme, a multi-epoch spectroscopic study of 88 early B-type binary candidates in the 30 Doradus region of the Large Magellanic Cloud (LMC). From radial-velocity analysis of 29 observational epochs, we confirm the binary status of 64 of our targets, comprising 50 SB1 and 14 SB2 B-type binaries. A further 20 systems (classified as SB1*) show clear signs of periodicity but with more tentative periods. Orbital solutions are presented for these 84 systems, providing the largest homogeneous sample to date of the binary properties of early B-type stars. Our derived orbital-period distribution is generally similar to those for samples of more massive (O-type) binaries in both the LMC and the Galaxy. This similarity with the properties of the more massive O-type binaries is important as early B-type stars are expected to account for the majority of core-collapse supernovae. Differences in the period distributions of the different samples start to increase above 4 d, and are also present between the earliest (B0-0.7) and later-type (B1-2.5) systems within the BBC sample, although further study is required to understand if this is an observational bias or a real physical effect. We have examined the semi-amplitude velocities and orbital periods of our sample to identify potential candidates that could hide compact companions. Comparing with probability distributions of finding black hole companions to OB-type stars from a recent theoretical study, we have found 16 binaries in the higher probability region that warrant further study.
Jupiter’s X-ray aurora during UV dawn storms and injections as observed byXMM–Newton, Hubble, andHisaki
Authors: Wibisono A D , Branduardi-Raymont G , Dunn W R , Kimura T , Coates A J , Grodent D , Yao Z H , Kita H , Rodriguez P , Gladstone G R , Bonfond B , Haythornthwaite R P
Published: July 2021

We present results from a multiwavelength observation of Jupiter’s northern aurorae, carried out simultaneously by XMM–Newton, the Hubble Space Telescope (HST), and the Hisaki satellite in 2019 September. HST images captured dawn storms and injection events in the far-ultraviolet aurora several times during the observation period. Magnetic reconnection occurring in the middle magnetosphere caused by internal drivers is thought to start the production of those features. The field lines then dipolarize, which injects hot magnetospheric plasma from the reconnection site to enter the inner magnetosphere. Hisaki observed an impulsive brightening in the dawnside Io plasma torus (IPT) during the final appearance of the dawn storms and injection events, which is evidence that a large-scale plasma injection penetrated the central IPT between 6 and 9RJ (Jupiter radii). The extreme ultraviolet aurora brightened and XMM–Newton detected an increase in the hard X-ray aurora count rate, suggesting an increase in electron precipitation. The dawn storms and injections did not change the brightness of the soft X-ray aurora and they did not ‘switch-on’ its commonly observed quasi-periodic pulsations. Spectral analysis of the X-ray aurora suggests that the precipitating ions responsible for the soft X-ray aurora were iogenic and that a power-law continuum was needed to fit the hard X-ray part of the spectra. The spectra coincident with the dawn storms and injections required two power-law continua to get good fits.
The H i angular momentum–mass relation
Authors: Kurapati Sushma , Chengalur Jayaram N , Verheijen Marc A W
Published: July 2021

We study the relationship between the H i specific angular momentum ($\rm j_{g}$) and the H i mass ($\rm M_{g}$) for a sample of galaxies with well-measured H i rotation curves. We find that the relation is well described by an unbroken power law $\rm j_{g}$ ∝ $\rm M_{g}$α over the entire mass range (107–1010.5 M⊙), with α = 0.89 ± 0.05 (scatter 0.18 dex). This is in reasonable agreement with models which assume that evolutionary processes maintain H i discs in a marginally stable state. The slope we observe is also significantly different from both the j ∝ M2/3 relation expected for dark matter haloes from tidal torquing models and the observed slope of the specific angular momentum–mass relation for the stellar component of disc galaxies. Our sample includes two H i-bearing ultra-diffuse galaxies, and we find that their angular momentum follows the same relation as other galaxies. The only discrepant galaxies in our sample are early-type galaxies with large rotating H i discs, which are found to have significantly higher angular momentum than expected from the power-law relation. The H i discs of all these early-type galaxies are misaligned or counter-rotating with respect to the stellar discs, consistent with the gas being recently accreted. We speculate that late-stage wet mergers, as well as cold flows play a dominant role in determining the kinematics of the baryonic component of galaxies as suggested by recent numerical simulations.
How does the shape of gamma-ray bursts’ pulses affect the duration distribution?
Authors: Tarnopolski Mariusz
Published: July 2021

Gamma-ray bursts (GRBs) come in two types, short and long. The distribution of logarithmic durations of long GRBs is asymmetric rather than Gaussian. Such an asymmetry, when modelled with a mixture of Gaussian distributions, requires an introduction of an additional component, often associated with another class of GRBs. However, when modelled with inherently asymmetric distributions, there is no need for such a component. The cosmological dilation was already ruled out as a source of the asymmetry, hence its origin resides in the progenitors. GRB light curves (LCs) are usually well described by a series of fast-rise-exponential-decay pulses. A statistical analysis of ensembles of simulated LCs shows that the asymmetry is a natural consequence of the pulse shape and the multi-pulse character of the LCs.
Interstellar objects outnumber Solar system objects in the Oort cloud
Authors: Siraj A , Loeb A
Published: July 2021

Here, we show that the detection of Borisov implies that interstellar objects outnumber Solar system objects in the Oort cloud, whereas the reverse is true near the Sun due to the stronger gravitational focusing of bound objects. This hypothesis can be tested with stellar occultation surveys of the Oort cloud. Furthermore, we demonstrate that $\sim 1 {{\ \rm per\ cent}}$ of carbon and oxygen in the Milky Way Galaxy may be locked in interstellar objects, implying a heavy element budget for interstellar objects comparable to the heavy element budget of the minimum mass Solar nebula model. There is still considerable uncertainty regarding the size distribution of the interstellar objects.
Evolutionary Sparse Learning for Phylogenomics
Authors: Kumar Sudhir , Sharma Sudip
Published: July 2021

We introduce a supervised machine learning approach with sparsity constraints for phylogenomics, referred to as evolutionary sparse learning (ESL). ESL builds models with genomic loci—such as genes, proteins, genomic segments, and positions—as parameters. Using the Least Absolute Shrinkage and Selection Operator, ESL selects only the most important genomic loci to explain a given phylogenetic hypothesis or presence/absence of a trait. ESL models do not directly involve conventional parameters such as rates of substitutions between nucleotides, rate variation among positions, and phylogeny branch lengths. Instead, ESL directly employs the concordance of variation across sequences in an alignment with the evolutionary hypothesis of interest. ESL provides a natural way to combine different molecular and nonmolecular data types and incorporate biological and functional annotations of genomic loci in model building. We propose positional, gene, function, and hypothesis sparsity scores, illustrate their use through an example, and suggest several applications of ESL. The ESL framework has the potential to drive the development of a new class of computational methods that will complement traditional approaches in evolutionary genomics, particularly for identifying influential loci and sequences given a phylogeny and building models to test hypotheses. ESL’s fast computational times and small memory footprint will also help democratize big data analytics and improve scientific rigor in phylogenomics.