bluuebunny/crossref_metadata_2025 huggingface dataset:
Effective acoustic metamaterial homogenization based on Hamilton's principle with a multiple scales approximation
Authors: Muhlestein Michael B.
Published: May 2020

This paper derives and demonstrates a one-dimensional acoustic metamaterial homogenization method. The homogenization method uses a multiple-scales approximation with Hamilton's principle, a weak-form representation of the dynamic equation. While the multiple-scales approximation makes the predicted effective material properties of this method inexact, the method is shown to be highly versatile. Analytical and numerical examples are given showing the ability of the homogenization method to account for viscosity and finite-amplitude effects.
Social Media Use Among Olympians and Sport Journalists in Hungary
Authors: Kovacs Agnes , Doczi Tamas , Antunovic Dunja
Published: May 2020

The Olympic Games are among the most followed events in the world, so athletes who participate there are exceptionally interesting for the media. This research investigated Olympians’ social media use, sport journalists’ attitudes about Olympians’ social media use, and the role of social media in the relationship between Olympians and sport journalists in Hungary. The findings suggest that most Hungarian Olympians do not think that being on social media is an exceptionally key issue in their life, and a significant portion of them do not have public social media pages. However, sport journalists would like to see more information about athletes on social media platforms. The Hungarian case offers not only a general understanding of the athlete–journalist relationship, and the role of social media in it, but also insight into the specific features of the phenomenon in a state-supported, hybrid sport economy.
Practitioner Perspectives on the Barriers Associated With Youth-to-Senior Transition in Elite Youth Soccer Academy Players
Authors: Mitchell Tom , Gledhill Adam , Nesti Mark , Richardson Dave , Littlewood Martin
Published: May 2020

There are concerns surrounding the lack of players making the transition from youth to professional status within English professional soccer. Stakeholders, such as coaches, have been largely overlooked by researchers often focussing on player experiences. The authors aimed to explore soccer practitioner perceptions of the debilitating factors associated with youth-to-senior progression. Practitioners were chosen as they inform the working practices and are the cultural architects of the environment in which players operate. Interviews were conducted with 18 soccer practitioners (male = 17 and female = 1). These included coaches (n = 6), academy managers (n = 8), and staff involved with education and welfare (n = 4). The data were thematically analysed, and four themes were identified (cultural climate, working practices, occupational hazards, and social challenges). The analysis provided a clear picture of the transition landscape faced by players seeking to make the youth-to-senior transition through the eyes of soccer practitioners. The findings present a novel viewpoint to facilitate reflection around their own practice when managing youth-to-senior transitions. Further research is needed to triangulate player experiences and operational aspects of facilitating transitions, which could lead to the creation of best practice guidance.
Clustering of Domain-Specific Sedentary Behaviors and Their Association With Physical Function Among Community-Dwelling Older Adults
Authors: Mitsutake Seigo , Shibata Ai , Ishii Kaori , Amagasa Shiho , Kikuchi Hiroyuki , Fukushima Noritoshi , Inoue Shigeru , Oka Koichiro
Published: May 2020

Background: The present study examined the cluster of domain-specific sedentary behaviors (SBs) and their associations with physical function among community-dwelling older adults to identify the target groups that require intervention for SBs. Methods: A total of 314 older adults who participated in a population-based cross-sectional survey and an on-site functional assessment in Matsudo City in Chiba participated in this study. Participants were asked to report the daily average of 6 domain-specific SBs. To identify the cluster of domain-specific SBs, hierarchical cluster analysis was performed using the Ward method. Analysis of covariance adjusted for sociodemographic factors, exercise habit, chronic disease, and total SB time was performed to examine the associations between each cluster and physical functional status. Results: The average age of the participants was 74.5 (5.2) years. The 4 clusters identified were leisure cluster, low cluster, work and personal computer use cluster, and television viewing cluster. The analysis of covariance adjusted for covariates showed that grip strength (P = .01), maximum walking speed (P = .03), and 1-leg standing time (P = .03) were significantly poorer in the television viewing cluster than other clusters. Conclusions: It has been concluded that the television viewing group identified as a high-risk group of physical functional decline; therefore, interventions targeting this group are needed to prevent physical functional decline.
Long-Term Nutrient Enrichment of an Oligotroph-Dominated Wetland Increases Bacterial Diversity in Bulk Soils and Plant Rhizospheres
Authors: Bledsoe Regina B. , Goodwillie Carol , Peralta Ariane L.
Published: May 2020

Over the last century, humans have substantially altered nitrogen and phosphorus cycling. Use of synthetic fertilizer and burning of fossil fuels and biomass have increased nitrogen and phosphorus deposition, which results in unintended fertilization of historically low-nutrient ecosystems. With increased nutrient availability, plant biodiversity is expected to decline, and the abundance of copiotrophic taxa is anticipated to increase in bacterial communities. Here, we address how bacterial communities associated with different plant functional types (forb, grass) shift due to long-term nutrient enrichment. Unlike other studies, results revealed an increase in bacterial diversity, particularly of oligotrophic bacteria in fertilized plots. We observed that nutrient addition strongly determines forb and grass rhizosphere composition, which could indicate different metabolic preferences in the bacterial communities. This study highlights how long-term fertilization of oligotroph-dominated wetlands could alter diversity and metabolism of rhizosphere bacterial communities in unexpected ways.
HIV Is Associated with Modified Humoral Immune Responses in the Setting of HIV/TB Coinfection
Authors: van Woudenbergh Esther , Irvine Edward B. , Davies Leela , de Kock Marwou , Hanekom Willem A. , Day Cheryl L. , Fortune Sarah , Alter Galit
Published: May 2020

TB is the leading cause of death from a single infectious agent globally, followed by HIV. Furthermore, TB represents the leading cause of death among people with HIV. HIV is known to cause severe defects in T cell immunity, rendering HIV/TB-coinfected individuals more susceptible to TB disease progression and complicating accurate TB disease diagnosis. Here, we demonstrate that HIV infection is additionally associated with severely compromised antibody responses, particularly in individuals with active TB. Moreover, despite the influence of HIV infection, antibody profiles still allow accurate classification of individuals with active versus latent TB. These findings reveal novel immunologic challenges associated with HIV/TB coinfection and additionally provide a basis with which to leverage the key antibody features identified to potentially combat TB globally via next-generation therapeutic or diagnostic design.
Genomewide Stabilization of mRNA during a “Feast-to-Famine” Growth Transition in Escherichia coli
Authors: Morin Manon , Enjalbert Brice , Ropers Delphine , Girbal Laurence , Cocaign-Bousquet Muriel
Published: May 2020

The ability to rapidly respond to changing nutrients is crucial for
E. coli
to survive in many environments, including the gut. Reorganization of gene expression is the first step used by bacteria to adjust their metabolism accordingly. It involves fine-tuning of both transcription (transcriptional regulation) and mRNA stability (posttranscriptional regulation). While the forms of transcriptional regulation have been extensively studied, the role of mRNA stability during a metabolic switch is poorly understood. Investigating
E. coli
genomewide transcriptome and mRNA stability during metabolic transitions representative of the carbon source fluctuations in many environments, we have documented the role of mRNA stability in the response to nutrient changes. mRNAs are globally stabilized during carbon depletion. For a few genes, this leads directly to expression upregulation. As these genes are regulators of stress responses and metabolism, our work sheds new light on the likely importance of posttranscriptional regulations in response to environmental stress.
Extreme Viral Partitioning in a Marine-Derived High Arctic Lake
Authors: Labbé Myriam , Girard Catherine , Vincent Warwick F. , Culley Alexander I.
Published: May 2020

The Arctic is warming at an accelerating pace, and the rise in temperature has increasing impacts on the Arctic biome. Lakes are integrators of their surroundings and thus excellent sentinels of environmental change. Despite their importance in the regulation of key microbial processes, viruses remain largely uncharacterized in Arctic lacustrine environments. We sampled a highly stratified meromictic lake near the northern limit of the Canadian High Arctic, a region in rapid transition due to climate change. We found that the different layers of the lake harbored viral communities that were strikingly dissimilar and highly divergent from known viruses. Viruses were more abundant in the deepest part of the lake containing ancient Arctic Ocean seawater that was trapped during glacial retreat and were genomically unlike any viruses previously described. This research demonstrates the complexity and novelty of viral communities in an environment that is vulnerable to ongoing perturbation.
Rapid cooling of the Rustenburg Layered Suite of the Bushveld Complex (South Africa): Insights from biotite 40Ar/39Ar geochronology
Authors: Setera Jacob B. , VanTongeren Jill A. , Turrin Brent D. , Swisher Carl C.
Published: May 2020

Despite their importance to understanding magma chamber processes and the formation of economically viable precious metal deposits, the cooling histories of layered mafic intrusions remain enigmatic due to limited geochronologic constraints. We provide a comprehensive 40Ar/39Ar study of biotite throughout the Rustenburg Layered Suite (RLS) of the Bushveld Complex, South Africa. Analyses of individual biotite grains from 10 samples, encompassing ∼5.5 km of RLS stratigraphy, yielded weighted mean plateau ages that all overlap at 2σ (α-95% confidence level) and range from 2056.3 ± 3.2 Ma to 2052.0 ± 7.6 Ma (2σ). A weighted mean of all biotite plateau ages yielded an age of 2054.47 ± 0.84 Ma (2σ, n = 30, mean square of weighted deviates = 0.23, P = 1.00; ±21 Ma fully propagated). The overlap between our 40Ar/39Ar biotite and published U-Pb zircon ages suggests that the RLS cooled rapidly to the closure temperature of biotite, with cooling rates on the order of 1000 °C m.y.–1 throughout the stratigraphy. Thermal modeling requires enhanced heat loss, due to the hydrothermal system associated with the emplacement of the RLS, to produce the inferred rapid cooling rates. Previously reported young 40Ar/39Ar biotite ages from the UG-2 and MG-1 chromitite seams and the Merensky Reef are likely a product of localized late-stage circulation of hydrothermal fluids. The lack of similarly young 40Ar/39Ar biotite ages from the remainder of the stratigraphy suggests that late-stage hydrothermal events were potentially localized to chromitites and the Merensky Reef.
Uplift and exhumation in Haida Gwaii driven by terrane translation and transpression along the southern Queen Charlotte fault, Canada
Authors: Schoettle-Greene Philip , Duvall Alison R. , Blythe Ann , Morley Eric , Matthews William , LaHusen Sean R.
Published: May 2020

The mountainous archipelago of Haida Gwaii abuts the transpressive Pacific–North American plate margin north of the Cascadia subduction zone (northwestern North America). Topography on Haida Gwaii has been attributed to either dynamic uplift supported by subduction initiation or crustal shortening driven by shear adjacent the plate-bounding Queen Charlotte fault. In order to resolve how intraplate strain is accommodated, we obtained thermochronometry data from 20 bedrock samples on Haida Gwaii, including zircon (U-Th)/He, apatite (U-Th-Sm)/He, and apatite fission-track dates. With dates ranging from 5 to 60 Ma, we interpret exhumation rates increasing in proximity to the Queen Charlotte fault and leading to a maximum of 6 km of exhumation since 20 Ma. The onset of exhumation significantly predates the purported initiation of subduction, precluding a direct relationship between subduction initiation and the development of topography in the archipelago. Instead, exhumation onset correlates with passage of the Yakutat terrane, suggesting that North America was deformed and Haida Gwaii uplifted during terrane translation. Steady or slightly decreasing exhumation rate since the Miocene is at odds with estimated increases to intraplate convergence over this time, ruling out crustal shortening in Haida Gwaii as the only response to transpression between North America and the Pacific. From this, we conclude that plate convergence is accommodated through basin inversion and internal shortening in the North American and Pacific plates as well as potential underthrusting of the Pacific plate beneath North America.
Effects of yoga on depressive symptoms in people with mental disorders: a systematic review and meta-analysis
Authors: Brinsley Jacinta , Schuch Felipe , Lederman Oscar , Girard Danielle , Smout Matthew , Immink Maarten A , Stubbs Brendon , Firth Joseph , Davison Kade , Rosenbaum Simon
Published: May 2020

Objective

To assess whether physically active yoga is superior to waitlist control, treatment as usual and attention control in alleviating depressive symptoms in people with a diagnosed mental disorder recognised by the Diagnostic and Statistical Manual of Mental Disorders (DSM).

Design

Systematic review and meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

Data sources

Data were obtained from online databases (MEDLINE, EMBASE, PsychINFO, CENTRAL, EMCARE, PEDro). The search and collection of eligible studies was conducted up to 14 May 2019 (PROSPERO registration No CRD42018090441).

Eligibility criteria for selecting studies

We included randomised controlled trials with a yoga intervention comprising ≥50% physical activity in adults with a recognised diagnosed mental disorder according to DSM-3, 4 or 5.

Results

19 studies were included in the review (1080 participants) and 13 studies were included in the meta-analysis (632 participants). Disorders of depression, post-traumatic stress, schizophrenia, anxiety, alcohol dependence and bipolar were included. Yoga showed greater reductions in depressive symptoms than waitlist, treatment as usual and attention control (standardised mean difference=0.41; 95% CI −0.65 to −0.17; p<0.001). Greater reductions in depressive symptoms were associated with higher frequency of yoga sessions per week (β=−0.44, p<0.01).
Association of dairy consumption with metabolic syndrome, hypertension and diabetes in 147 812 individuals from 21 countries
Authors: Bhavadharini Balaji , Dehghan Mahshid , Mente Andrew , Rangarajan Sumathy , Sheridan Patrick , Mohan Viswanathan , Iqbal Romaina , Gupta Rajeev , Lear Scott , Wentzel-Viljoen Edelweiss , Avezum Alvaro , Lopez-Jaramillo Patricio , Mony Prem , Varma Ravi Prasad , Kumar Rajesh , Chifamba Jephat , Alhabib Khalid F , Mohammadifard Noushin , Oguz Aytekin , Lanas Fernando , Rozanska Dorota , Bengtsson Bostrom Kristina , Yusoff Khalid , Tsolkile Lungiswa P , Dans Antonio , Yusufali Afzalhussein , Orlandini Andres , Poirier Paul , Khatib Rasha , Hu Bo , Wei Li , Yin Lu , Deeraili Ai , Yeates Karen , Yusuf Rita , Ismail Noorhassim , Mozaffarian Dariush , Teo Koon , Anand Sonia S , Yusuf Salim
Published: May 2020

Objective

Our aims were to assess the association of dairy intake with prevalence of metabolic syndrome (MetS) (cross-sectionally) and with incident hypertension and incident diabetes (prospectively) in a large multinational cohort study.

Methods

The Prospective Urban Rural Epidemiology (PURE) study is a prospective epidemiological study of individuals aged 35 and 70 years from 21 countries on five continents, with a median follow-up of 9.1 years. In thecross-sectional analyses, we assessed the association of dairy intake with prevalent MetS and its components among individuals with information on the five MetS components (n=112 922). Forthe prospective analyses, we examined the association of dairy with incident hypertension (in 57 547 individuals free of hypertension) and diabetes (in 131 481 individuals free of diabetes).

Results

In cross-sectional analysis, higher intake of total dairy (at least two servings/day compared with zero intake; OR 0.76, 95% CI 0.71 to 0.80, p-trend<0.0001) was associated with a lower prevalence of MetS after multivariable adjustment. Higher intakes of whole fat dairy consumed alone (OR 0.72, 95% CI 0.66 to 0.78, p-trend<0.0001), or consumed jointly with low fat dairy (OR 0.89, 95% CI 0.80 to 0.98, p-trend=0.0005), were associated with a lower MetS prevalence. Low fat dairy consumed alone was not associated with MetS (OR 1.03, 95% CI 0.77 to 1.38, p-trend=0.13). In prospective analysis, 13 640 people with incident hypertension and 5351 people with incident diabetes were recorded. Higher intake of total dairy (at least two servings/day vs zero serving/day) was associated with a lower incidence of hypertension (HR 0.89, 95% CI 0.82 to 0.97, p-trend=0.02) and diabetes (HR 0.88, 95% CI 0.76 to 1.02, p-trend=0.01). Directionally similar associations were found for whole fat dairy versus each outcome.

Conclusions

Higher intake of whole fat (but not low fat) dairy was associated with alower prevalenceof MetS and most of its component factors, and with alower incidenceof hypertension and diabetes. Our findings should be evaluated in large randomized trials of the effects of whole fat dairy on the risks of MetS, hypertension, and diabetes.
Developing a typology of the roles public contributors undertake to establish legitimacy: a longitudinal case study of patient and public involvement in a health network
Authors: Barker Jacqueline , Moule Pam , Evans David , Phillips Wendy , Leggett Nick
Published: May 2020

Objective

To identify how public contributors established their legitimacy in the functioning of a patient and public involvement programme at a health network.

Design

A longitudinal case study with three embedded units (projects) involving public contributors. Interviews (n=24), observations (n=27) and documentary data collection occurred over 16 months.

Setting

The West of England Academic Health Science Network (WEAHSN), 1 of 15 regional AHSNs in England.

Participants

Interviews were conducted with public contributors (n=5) and professionals (n=19) who were staff from the WEAHSN, its member organisations and its partners.

Results

Public contributors established their legitimacy by using nine distinct roles: (1) lived experience, as a patient or carer; (2) occupational knowledge, offering job-related expertise; (3) occupational skills, offering aptitude developed through employment; (4) patient advocate, promoting the interests of patients; (5) keeper of the public purse, encouraging wise spending; (6) intuitive public, piloting materials suitable for the general public; (7) fresh-eyed reviewer, critiquing materials; (8) critical friend, critiquing progress and proposing new initiatives and (9) boundary spanner, urging professionals to work across organisations. Individual public contributors occupied many, but not all, of the roles.

Conclusions

Lived experience is only one of nine distinct public contributor roles. The WEAHSN provided a benign context for the study because in a health network public contributors are one of many parties seeking to establish legitimacy through finding valuable roles. The nine roles can be organised into a typology according to whether the basis for legitimacy lies in: the public contributor’s knowledge, skills and experience; citizenship through the aspiration to achieve a broad public good; or being an outsider. The typology shows how public contributors can be involved in work where lived experience appears to lack relevance: strategic decision making; research unconnected to particular conditions; or acute service delivery.
Changes in performance during repeated in-situ simulations with different
cases
Authors: Berg Helen , Båtnes Ronald , Steinsbekk Aslak
Published: May 2020

Introduction

The aim was to describe changes in the performance of clinical actions,
during repeated in-situ simulations with different cases, by teams of
healthcare professionals with different experiences of the systematic clinical
observation of deteriorating patients, after an introduction to the Airways,
Breathing, Circulation, Disability, Environment/Exposure (ABCDE)
approach.

Methods

A descriptive observational study was conducted of repeated in-situ
simulations using a patient simulator (SimMan 3G), carried out by teams in a
public nursing home (NH, least experienced), an out-of-hours general practice
(OOH-GP) service and a hospital emergency department (ED, most experienced).
The cases had similar clinical presentations but different underlying diagnoses
unknown to the teams. Four blinded clinical experts independently assessed the
simulations on the basis of transcripts, providing comments, an overall score
and scores for the clinical actions.

Results

The assessors commented on the overall lack of a systematic ABCDE approach
in the NH and OOH-GP in all simulations, while the comments for the ED
concerned the choice of treatment. Across the teams, the overall score was
highest in the first simulation and second highest in the third simulation. The
team in the NH received low overall scores for all simulations, but the last
simulation received markedly better scores on the clinical actions. The teams
in the OOH-GP and ED had no such clear pattern in the scores for clinical
actions and thus no indications of improvement with repeated
simulations.

Conclusion

The observation in this study was that the overall assessment by the
blinded assessors showed no consistent improvement in clinical actions from
repeated in-situ simulations, and the teams did not seem to adhere to the ABCDE
approach throughout the simulations. This indicates that the teams were not
able to apply their newly acquired experiences of using the ABCDE approach from
one case to another, different case.
Myelin oligodendrocyte glycoprotein-associated disorders are associated with HLA subtypes in a Chinese paediatric-onset cohort
Authors: Sun Xiaobo , Qiu Wei , Wang Jingqi , Wang Shisi , Wang Yuge , Zhong Xiaonan , Liu Chunxin , Cui Chunping , Hong Hai , Yang Hui , Li Xiao-Jing , Lu Zhengqi , Hu Xueqiang , Kermode Allan G , Peng Lisheng
Published: May 2020

Objective

Myelin oligodendrocyte glycoprotein-associated disorders (MOGADs) are a rare new neurological autoimmune disease with unclear pathogenesis. Since a linkage of the disease to the human leucocyte antigen (HLA) has not been shown, we here investigated whether MOGAD is associated with the HLA locus.

Methods

HLA genotypes of 95 patients with MOGADs, assessed between 2016 and 2018 from three academic centres, were compared with 481 healthy Chinese Han individuals. Patients with MOGADs included 51 paediatric-onset and 44 adult-onset cases. All patients were seropositive for IgG targeting the myelin oligodendrocyte glycoprotein (MOG).

Results

Paediatric-onset MOGAD was associated with theDQB1*05:02–DRB1*16:02alleles (OR=2.43; OR=3.28) or haplotype (OR=2.84) ofHLAclass II genes. The prevalence of these genotypes in patients with paediatric-onset MOGAD was significantly higher than healthy controls (padj=0.0154; padj=0.0221; padj=0.0331). By contrast, adult-onset MOGAD was not associated with any HLA genotype. Clinically, patients with theDQB1*05:02–DRB1*16:02haplotype exhibited significantly higher expanded disability status scale scores at onset (p=0.004) and were more likely to undergo a disease relapse (p=0.030). HLA–peptide binding prediction algorithms and computational docking analysis provided supporting evidence for the close relationship between the MOG peptide subunit andDQB1*05:02allele. In vitro results indicated that site-specific mutations of the predicted target sequence reduced the antigen–antibody binding, especially in the paediatric-onset group withDQB1*05:02allele.

Conclusions

This study demonstrates a possible association between specificHLAclass II alleles and paediatric-onset MOGAD, providing evidence for the conjecture that different aetiology and pathogenesis likely underlie paediatric-onset and adult-onset cases of MOGAD.
Incidental COVID-19 related lung apical findings on stroke CTA during the COVID-19 pandemic
Authors: Kihira Shingo , Schefflein Javin , Chung Michael , Mahmoudi Keon , Rigney Brian , Delman Bradley N , Mocco J , Doshi Amish , Belani Puneet
Published: May 2020

Background

Authors have noticed an increase in lung apex abnormalities on CT angiography (CTA) of the head and neck performed for stroke workup during the coronavirus disease 2019 (COVID-19) pandemic.

Objective

To evaluate the incidence of these CTA findings and their relation to COVID-19 infection.

Methods

In this retrospective multicenter institutional review board-approved study, assessment was made of CTA findings of code patients who had a stroke between March 16 and April 5, 2020 at six hospitals across New York City. Demographic data, comorbidities, COVID-19 status, and neurological findings were collected. Assessment of COVID-19 related lung findings on CTA was made blinded to COVID-19 status. Incidence rates of COVID-19 related apical findings were assessed in all code patients who had a stroke and in patients with a stroke confirmed by imaging.

Results

The cohort consisted of a total of 118 patients with mean±SD age of 64.9±15.7 years and 57.6% (68/118) were male. Among all code patients who had a stroke, 28% (33/118) had COVID-19 related lung findings. RT-PCR was positive for COVID-19 in 93.9% (31/33) of these patients with apical CTA findings.

Among patients who had a stroke confirmed by imaging, 37.5% (18/48) had COVID-19 related apical findings. RT-PCR was positive for COVID-19 in all (18/18) of these patients with apical findings.

Conclusion

The incidence of COVID-19 related lung findings in stroke CTA scans was 28% in all code patients who had a stroke and 37.5% in patients with a stroke confirmed by imaging. Stroke teams should closely assess the lung apices during this COVID-19 pandemic as CTA findings may be the first indicator of COVID-19 infection.
Conformal and kinetic couplings as two Jordan frames of the same theory
Authors: Gal’tsov D. V.
Published: May 2020

Certain scalar-tensor (ST) theories with non-minimal coupling of the scalar field to curvature may admit an Einstein frame representation, where gravity is described by the Einstein–Hilbert action plus the scalar sector. Between them, some theories exactly coincide in their respective Einstein frames. If transformations between Jordan and Einstein frames are invertible, these theories can be associated with two Jordan frames of the unique theory. Such successive dualities can connect theories with non-derivative coupling, like $$R\phi ^2$$Rϕ2, with derivatively coupled theories, like Horndeski and DHOST. In absence of matter, these are equivalent, though looking very different. We show the existence of a successive duality between the $$R\phi ^2$$Rϕ2 theory and a recently found Palatini kinetically coupled theory, which both look in their Einstein frames as Einstein theory minimally coupled to scalar. Transforming singular exact solutions of the latter to Jordan frames, we compare desingularization properties of the above two theories which both violate the null energy condition. It is found that kinetically coupled theory has stronger desingularization features, exhibiting possibility of Genesis-type behavior of the homogeneous and isotropic cosmological solutions.
Lagrangian formulation of Omori’s law and analogy with the cosmic Big Rip
Authors: Faraoni Valerio
Published: May 2020

A recent model predicting Omori’s law giving the number of aftershocks per unit time following an earthquake involves a differential equation analogous to the Friedmann equation of cosmology. The beforeshock phase is analogous to an accelerating universe approaching a Big Rip, the main shock to the Big Rip singularity, and the aftershock to a contracting universe. The analogy provides some physical intuition and Lagrangian and Hamiltonian formulations for Omori’s law and its generalizations.
The Parallel Seeding Algorithm for k-Means Problem with Penalties
Authors: Li Min , Xu Dachuan , Yue Jun , Zhang Dongmei
Published: May 2020

As a classic NP-hard problem in machine learning and computational geometry, the [Formula: see text]-means problem aims to partition a data point set into [Formula: see text] clusters such that the sum of the squared distance from each point to its nearest center is minimized. The [Formula: see text]-means problem with penalties, denoted by [Formula: see text]-MPWP, generalizing the [Formula: see text]-means problem, allows that some points can be paid some penalties instead of being clustered. In this paper, we study the seeding algorithm of [Formula: see text]-MPWP and propose a parallel seeding algorithm for [Formula: see text]-MPWP along with the corresponding theoretical analysis.
Critical Multipliers in Semidefinite Programming
Authors: Zhang Tianyu , Zhang Liwei
Published: May 2020

It was proved in Izmailov and Solodov (2014). Newton-Type Methods for Optimization and Variational Problems, Springer] that the existence of a noncritical multiplier for a (smooth) nonlinear programming problem is equivalent to an error bound condition for the Karush–Kuhn–Thcker (KKT) system without any assumptions. This paper investigates whether this result still holds true for a (smooth) nonlinear semidefinite programming (SDP) problem. The answer is negative: the existence of noncritical multiplier does not imply the error bound condition for the KKT system without additional conditions, which is illustrated by an example. In this paper, we obtain characterizations, in terms of the problem data, the critical and noncritical multipliers for a SDP problem. We prove that, for the SDP problem, the noncriticality property can be derived from the error bound condition for the KKT system without any assumptions, and we give an example to show that the noncriticality does not imply the error bound for the KKT system. We propose a set of assumptions under which the error bound condition for the KKT system can be derived from the noncriticality property. a Finally, we establish a new error bound for [Formula: see text]-part, which is expressed by both perturbation and the multiplier estimation.
Cosmological constant in coherent quantum gravity
Authors: Hogan Craig
Published: May 2020

It is argued that quantum states of geometry, like those of particles, should be coherent on light cones of any size. An exact classical solution, the gravitational shock wave of a relativistic point particle, is used to estimate gravitational drag from coherent energy flows, and the expected gravitational effect of virtual transverse vacuum energy fluctuations on surfaces of causal diamonds. It is proposed that the appropriately spacetime-averaged gravitational effect of the Standard Model vacuum state leads to the observed small nonzero value of the cosmological constant, dominated by gravitational drag of virtual gluonic strings at the strong interaction scale.
NUMERICAL INVESTIGATION ON INFLUENCE OF VASCULAR STENOSIS RATE AND CURVATURE RADIUS ON PLAQUE VULNERABILITY IN STENTED VESSELS
Authors: JIANG XUDONG , LI PENGFEI , LIU ZHENG , TENG XIAOYAN
Published: May 2020

The high stresses on plaque wall experienced by stent implantation into a stenotic artery can go beyond the material strength of plaque tissue, potentially leading to plaque rupture. Two non-commercial stents with different link structures called S-type and N-type were taken into account, respectively. A non-linear finite element model was developed to investigate the influence of the stenosis level (i.e., 24%, 40%, and 50%) and arterial curvature radius (i.e., 6, 10, and 20[Formula: see text]mm) on the stress induced within the plaque tissue during stent expansion. The numerical results indicated that the severer stenosis level and more tortuous artery caused the higher stress on plaque wall. The maximal stresses on the plaque wall were in the fracture level of 1.79[Formula: see text]MPa for N-type stent, and 1.82[Formula: see text]MPa for S-type stent under the 50% stenosis rate and 6[Formula: see text]mm curvature radius. Due to smaller compliance mismatch to the curved vessel, the N-type stent was founded to induce less stress gradient on the plaque wall than that by the S-type stent. This suggests a lower risk of the plaque rupture for the N-type stent. This study showed how the arterial curvature radius and stenosis level were correlated with the plaque vulnerability. Therefore, it is possible to choose a suitable stent in terms of arterial stenosis geometry and thereby optimize the outcome of stenting procedure.
THE MODELING OF THE TEMPERATURE CHANGES AND DISTRIBUTION IN THE MYOCARDIUM
Authors: SHLYKOV VLADYSLAV , KOTOVSKYI VITALII , VIŠNIAKOV NIKOLAJ , ŠEŠOK ANDŽELA
Published: May 2020

This paper investigates the opportunities of applying the methods of noninvasive contactless diagnostics and numerical modeling for assessing the temperature gradient on the surface of the myocardium. These changes are observed on the surface of myocardium during hypo and hyperthermal processes, precisely during cardiopulmonary bypass (CPB). The 3D model of heat exchange in the myocardium is developed in the system MSC Sinda. Results of the performed measurements in the heart show that a noninvasive monitoring of the heart temperature using a thermographic camera in (CPB) conditions enables reliable measuring of the temperature of the myocardium during hypo and hyperthermal processes. The gradient of temperature on the surface of the heart may be usable as a diagnostic criterion for establishing ischemic zones on the surface of the myocardium.
A COMPARATIVE ANALYSIS OF THE EFFECTS OF TWO AUGMENTERS ON THE SENSITIVITY OF VERTEBRAL BIOMECHANICAL BEHAVIOR IN VERTEBROPLASTY
Authors: YUEWAN SUN , DONGMEI WANG , JINGCHUAN SUN , ANMIN LIU , JIANGANG SHI
Published: May 2020

The treatment of osteoporotic vertebral compression fractures (OVCFS) by transvertebral bone graft and augmentation (TBGA) has achieved satisfactory clinical results, but its biomechanical effects are not clear. The purpose of this study was to investigate the biomechanical effects of TBGA and compare the biomechanical sensitivity of the augmenter used in TBGA — a cylindrical enhancement device (CED) with bone cement. The finite element (FE) model of healthy segments T11-L3 (M1) was built, and two other models with L1 augmentation (M2, M3) were established to simulate CED and bone cement treatment, respectively. The stress and displacement distribution of the three models under five physiological loads were calculated and analyzed by the FE method. Based on the results, the sensitivities of biomechanical parameters to the degree of osteoporosis (DO) and loads were analyzed by linear fitting method using dummy variables. With the increase of DO, the CED is superior to bone cement in preventing the fractures of the augmented vertebral and the adjacent vertebral under the set loading conditions. Simulating TBGA method, the model 2 with L1 reconstructed was closer to the normal T11-L3 model in terms of sensitivity of stress and displacement under different loading conditions.
Fluorous phthalocyanines and subphthalocyanines
Authors: Yoshinaga Kosuke , Delage-Laurin Leo , Swager Timothy M.
Published: May 2020

Incorporating fluorine atoms into a molecule can endow it with various unique properties that enable materials applications. Selective solubility in fluorous solvents is achieved by a high fluorine content and selective partitioning into perfluorinated liquids over organic and aqueous phases provides orthogonal opportunities for chemistry and materials assembly. Although there is a growing number of partially fluorinated molecules, there are insufficient structural design principles to produce diverse fluorous soluble dyes. Herein, we report the synthesis of six fluorous phthalocyanine and subphthalocyanine dyes, and study their properties in the fluorous phase. Phthalocyanines generally display limited solubility and we also observed apparent aggregation in the fluorous phase. However, the nonplanar subphthalocyanines showed greater solubility. Subphthalocyanines also displayed fluorescence in selected solvents, and their emissive properties were investigated. The materials described expand the library of fluorous dyes and provide insights for the design of new molecules with fluorous solubility.
Multiple big q-Jacobi polynomials
Authors: Bouzeffour Fethi , Garayev Mubariz
Published: May 2020

Here, we investigate type II multiple big [Formula: see text]-Jacobi orthogonal polynomials. We provide their explicit formulae in terms of basic hypergeometric series, raising and lowering operators, Rodrigues formulae, third-order [Formula: see text]-difference equation, and we obtain recurrence relations.
OPTICS
Authors: Winkler Daniel A. , Carreira-Perpiñán Miguel Á. , Cerpa Alberto E.
Published: May 2020

Lawns, also known as turf, cover an estimated 128,000 km
2
in North America alone, with landscape requirements representing 30% of freshwater consumed in the residential domain. With this consumption comes a large amount of environmental, economic, and social incentive to make turf irrigation systems as efficient as possible. Recent work introduced the concept of distributed control in irrigation systems, but existing control strategies either do not take advantage of the distributed control, or do not revise the strategy over time in response to collected data. In this work, we introduce OPTICS, a data-driven control strategy that self-improves over time, adapts to the local specific conditions and weather changes, and requires virtually no human input in both setup and maintenance providing a
plug-and-play
system that requires minimal pre-deployment efforts. In addition to substantial improvements in ease-of-use, we find across 4 weeks of large-scale irrigation system deployment that OPTICS improves system efficiency by 12.0% in comparison to industry best and 3.3% in comparison to academic state of the art. Despite using less water, OPTICS also was found to improve quality of service by a factor of 4.0× compared to industry best and 2.5× compared to academic state of the art.
SCRIPT
Authors: Nahiyan Adib , Park Jungmin , He Miao , Iskander Yousef , Farahmandi Farimah , Forte Domenic , Tehranipoor Mark
Published: May 2020

Power side-channel attacks (SCAs) have been proven to be effective at extracting secret keys from hardware implementations of cryptographic algorithms. Ideally, the power side-channel leakage (PSCL) of hardware designs of a cryptographic algorithm should be evaluated as early as the pre-silicon stage (e.g., gate level). However, there has been little effort in developing computer-aided design (CAD) tools to accomplish this. In this article, we propose an automated CAD framework called
SCRIPT
to evaluate information leakage through side-channel analysis. SCRIPT starts by defining the underlying properties of the hardware implementation that can be exploited by side-channel attacks. It then utilizes information flow tracking (IFT) to identify registers that exhibit those properties and, therefore, leak information through the side-channel. Here, we develop an IFT-based side-channel vulnerability metric (
SCV
) that is utilized by SCRIPT for PSCL assessment. SCV is conceptually similar to the traditionally used signal-to-noise ratio (SNR) metric. However, unlike SNR, which requires thousands of traces from silicon measurements, SCRIPT utilizes formal methods to generate SCV-guided patterns/plaintexts, allowing us to derive SCV using only a few patterns (ideally as low as two) at gate level. SCV estimates PSCL vulnerability at pre-silicon stage based on the number of plaintexts required to attain a specific SCA success rate. The integration of IFT and pattern generation makes SCRIPT efficient, accurate, and generic to be applied to any hardware design. We validate the efficacy of the SCRIPT framework by demonstrating that it can effectively and accurately determine SCA success rates for different AES designs at pre-silicon stage. SCRIPT is orders of magnitude more efficient than traditional pre-silicon PSCL assessment (SNR-based), with an average evaluation time of 15 minutes; whereas, traditional PSCL assessment at pre-silicon stage would require more than a month. We also analyze the PSCL characteristic of the multiplication unit of RISC processor using SCRIPT to demonstrate SCRIPT’s applicability.
Time-efficient Missing Tag Identification in an Open RFID System
Authors: Wang Yanyan , Liu Jia , Wang Xia , Chen Xingyu , Yan Yingli , Chen Lijun
Published: May 2020

Radio Frequency IDentification (RFID) technology has been widely used in missing tag identification to reduce the economic loss caused by theft. Although many advanced works have been proposed, they cannot work properly in an open RFID system with unexpected tags. That is because the unexpected tags may reply to the reader when it is the missing tags’ turn, such that the replies are mistakenly treated as the missing tags’, leading to failure to detect the missing tags. To solve the problem, this article proposes an order-based missing tag identification protocol (OMTI) that efficiently identifies all missing tags even with the presence of unexpected tags. The key of OMTI is that we dynamically assign each tag an exclusive slot rather than use random hashes in traditional design. Namely, OMTI off-line serializes all known tags in advance by assigning each of them a unique and continuous slot, on-line identifies missing tags by checking tags’ responses in each slot, and dynamically updates the slot assignment to ensure the high efficiency of the next execution. Besides, we enhance OMTI to make it embrace newly added tags and spread to the multi-reader case from the single one. The simulation results demonstrate that OMTI can significantly reduce the identification time compared to the state-of-the-art.
Algorithmic Fault Detection for RRAM-based Matrix Operations
Authors: Liu Mengyun , Xia Lixue , Wang Yu , Chakrabarty Krishnendu
Published: May 2020

An RRAM-based computing system (RCS) provides an energy-efficient hardware implementation of vector-matrix multiplication for machine-learning hardware. However, it is vulnerable to faults due to the immature RRAM fabrication process. We propose an efficient fault tolerance method for RCS; the proposed method, referred to as extended-ABFT (X-ABFT), is inspired by algorithm-based fault tolerance (ABFT). We utilize row checksums and test-input vectors to extract signatures for fault detection and error correction. We present a solution to alleviate the overflow problem caused by the limited number of voltage levels for the test-input signals. Simulation results show that for a Hopfield classifier with faults in 5% of its RRAM cells, X-ABFT allows us to achieve nearly the same classification accuracy as in the fault-free case.
Approximate Counting CSP Seen from the Other Side
Authors: Bulatov Andrei A. , Živný Stanislav
Published: May 2020

In this article, we study the complexity of counting Constraint Satisfaction Problems (CSPs) of the form #CSP(
C
, -), in which the goal is, given a relational structure
A
from a class
C
of structures and an arbitrary structure
B
, to find the number of homomorphisms from
A
to
B
. Flum and Grohe showed that #CSP(
C
, -) is solvable in polynomial time if
C
has bounded treewidth [FOCS’02]. Building on the work of Grohe [JACM’07] on decision CSPs, Dalmau and Jonsson then showed that if
C
is a recursively enumerable class of relational structures of bounded arity, then, assuming FPT≠ #W[1], there are no other cases of #CSP(
C
, -) solvable exactly in polynomial time (or even fixed-parameter time) [TCS’04].

We show that, assuming FPT ≠ W[1] (under randomised parameterised reductions) and for
C
satisfying certain general conditions, #CSP(
C
,-) is not solvable even
approximately
for
C
of unbounded treewidth; that is, there is no fixed parameter tractable (and thus also not fully polynomial) randomised approximation scheme for #CSP(
C
, -). In particular, our condition generalises the case when
C
is closed undertaking minors.
Study on Varying Characteristics of Temperature Field and Moisture Field of Shallow Loess in the Freeze‐Thaw Period
Authors: Zhang Hui , Zhi Bin , Liu Enlong , Wang Tiehang
Published: May 2020

The moisture and the temperature variation of shallow loess during the freeze‐thaw process have tremendous influences on the freeze‐thaw disease and agricultural development. The present paper, based on the field test of the temperature and water content of the shallow loess in the seasonal frozen region, probes into the variation of the temperature and moisture fields of shallow loess in the freeze‐thaw period. Field test shows that the daily variation of surface temperature reaches the maximum with the peak temperature appearing around 14:00, and the time when the peak temperature appears gradually postpones as the depth increases. Moreover, the daily variation of soil temperature decreases with the increase of temperature, and the variation can be ignored given the depth of more than 30 cm. In addition, there is an obvious variation of moisture content in shallow soil under the action of freeze‐thaw cycles. In this regard, the coupled calculation model is proposed in this paper to simulate the dynamic variation of temperature and moisture in shallow soil in Bin County located in Western China under natural conditions, compare the calculation value with the measurement value, and further verify the rationality of the numerical calculation method and parameter selection. Furthermore, the variation law of the maximum frozen depth with the air temperature is obtained through the simulation of extreme cold climate conditions.
Group Recommender Systems Based on Members’ Preference for Trusted Social Networks
Authors: Wang Xiangshi , Su Lei , Zhou Qihang , Wu Liping
Published: May 2020

With the development of the Internet of Things (IoT), the group recommender system has also been extended to the field of IoT. The entities in the IoT are linked through social networks, which constitute massive amounts of data. In group activities such as group purchases and group tours, user groups often exhibit common interests and hobbies, and it is necessary to make recommendations for certain user groups. This idea constitutes the group recommender system. However, group members’ preferences are not fully considered in group recommendations, and how to use trusted social networks based on their preferences remains unclear. The focus of this paper is group recommendation based on an average strategy, where group members have preferential differences and use trusted social networks to correct for their preferences. Thus, the accuracy of the group recommender system in the IoT and big data environment is improved.