bluuebunny/crossref_metadata_2025 huggingface dataset:
SoftMax Neural Best Approximation
Authors: Almurieb Hawraa A , Bhaya Eman S
Published: June 2020

Neural networks have a great place in approximating nonlinear functions, especially those Lebesgue integrable functions that are approximated by FNNs with one hidden layer and sigmoidal functions. Various operators of neural networks have been defined and achieved to get good rates of approximation depending on the modulus of smoothness. Here we define a new neural network operator with a generalized sigmoidal function (SoftMax) to improve the rate of approximation of a Lebesgue integrable function Lp
, with p < 1, to be estimated using modulus of smoothness of order k. The importance of choosing SoftMax function as an activation function is its flexible properties and various applications.
Gamma Comultiplication and Full Stability
Authors: Abbas Mehdi S. , Hamad Balsam M.
Published: June 2020

Let be a Γ-ring with identity (not necessarily commutative), and M a left RΓ-module. Then M is called fully stable if θ(N) ⊆ N for each RΓ-submodule N of M and RΓ-homomorphism θ from N into M. Equivalently, for each element m in M we have

Rα

0

m
=

ϒ
M

α
0

(

ℓ
R

α
0

(

Rα

0

m
)
)

, in other words, each α0-cyclic RΓ-submodule Rα0
m satisfies the double annihilator condition.

In this paper we will introduce and study the notion of RΓ-modules in which every RΓ-submodule satisfies the double annihilator condition. Many properties and characterizations of this class of RΓ-modules are considering, and obtain some relatied results, as well as, their relationship with full stability.
Intuitionistic fuzzy Q-filters of Q-algebra
Authors: Abdullah H. K. , Naji R. S.
Published: June 2020

Our work aimed to focus on some types of intuitionistic fuzzy filters, which are known as intuitionistic fuzzy Q-filter and intuitionistic fuzzy complete Q-filter, in addition we aimed to find out the relationships among these types of filters and other characteristics of Q-algebra.
Operational characteristics of disc and spherical cathode electrodes in dc plasma discharge
Authors: Abd-Alwahed Estbrq A , Yahya Khalid A
Published: June 2020

In this work, the effective of shapes for disc and spherical cathode electrodes on the operational conditions of dc discharge has been studied. Paschen curve was studied of the two cathode shapes electrodes at the discharge voltage (0- 450 V) at 38 mm distance between the electrodes. Theoretically, the distributions of equipotential line and electric field before the minimum discharge voltage between the electrodes were estimated by using SIMION software. The study showed the effect of the geometry of the cathode electrode on the operational conditions where the discharge voltages require for the spherical shape was greater than the disc at minimum values in Paschen curve. The results showed a diagnostics of plasma using a single Langmuir probe that electron temperature and ion density for spherical cathode shape was higher than the disc by, 20% and 17.9% respectively.
Quality of medical microscope Image at different lighting condition
Authors: Abd-Alameer Shahad Ahmed , Daway Hazim G , Rashid Hayfa G.
Published: June 2020

A no- reference quality metrics is one of the challenging fields in image quality assessment. The aim of the research is measuring the quality of the microscope medical image such as blood smear and sample texture, at different lightness conditions by using two types of light sources are Tungsten and LED. To find the best light level at imaging, the no- reference quality metrics are calculated by using the histogram in a HL component in the wavelet transform. This measure is Compare with the other no-reference algorithms as entropy and average gradient by calculating the correlation coefficient between the subjective and objective methods. The results show that the proposed algorithm is a good measure of the quality of the medical microscope images at different lighting condition.
Antibacterial activity and Electrical properties of Prepared Graphene Oxide GO Hybrid Cupper Phthalocyanine (CuPc)
Authors: Jassim Saad A. , Kadhim Raheem G.
Published: June 2020

GO samples were prepared by Hummer‘s method. The Electrical properties of polymer composite Go-CuPc (graphene oxide-cupper phthalocyanines) prepared by spin coating technique were studied. Three different ratio of the prepared graphene oxide added to the pure cupper phthalocyanines (10%, 15%, 20%). It was found that there was a clear increasing in the concentration of carriers and a decreasing in the values of mobility at room temperature with increasing of doping ratio, the electrical conductivity increased with the increase of the concentration of GO, the value of activation energy decreased for all (GO/CuPc) thin films with adding concentration of GO. The antimicrobial properties of Graphene Oxide Modified Cupper Phthalocyanine were evaluated against Staphylococcus aureus, Gram-positive bacterium and sydomonus, Gram-negative one. Bacteriological tests were performed in Muller Hinton solid agar plates with different concentrations of graphene oxide particles. The inhibition zones as a function of added graphene oxide where studied, the results show that as the concentration of graphene oxide increased the inhibition zone increased also against both types of bacteria. When the ratio of added graphene oxide was (15%) maximum inhibitionzone has been calculated.
Investigation of strengths distributions of Gamow-Teller in sd and fp shell nuclei
Authors: Obaid Sarah M. , Tawfeek Huda M.
Published: June 2020

The strength distribution of Gamow-Teller (GT) in the 26Si→26Al, 28Si→28P, 42Sc→42Ca and 44Sc→44Ca transitions are calculated by using shell model with full basis which assume the valence nucleons in the sd and fp shells. The calculation of the shell model were conducted in the sd and fp shells without any restriction by using USDB and USDA interactions for sd shell and GXFP1A, KB3G and FPD6 effective interactions for fp shell. Our theoretical results of shell model calculations compared with the data obtained from (3He, t) and (p, n) charge-exchange reactions. Calculated B(GT) strength distributions agree well with the recently available experimental data and with the summed transition strengths B(GT).
Study of the Structural and Optical Properties of Ni-doped Co3O4 Thin Films Using Chemical Spray Pyrolysis Technique
Authors: Farhan Marwan M. , Khodair Ziad T. , Ibrahim Buthainah A.
Published: June 2020

Undoped and Ni-doped Cobalt oxide thin films (Co3O4:Ni) with doping percentage (3, 6, and 9%) have been prepared by chemical spray pyrolysis technique on glass substrates at (400 °C). The structural, surface morphology and optical properties were studied. XRD results showed that all the films were polycrystalline and had a cubic structure with preferred orientation (111) plane for all doping. The AFM images appear to be smooth and homogenous films. The optical properties showed that the transmittance decreased by increasing the percentage of Ni, and the direct optical band gap decreased from (2.53 eV) to (2.32 eV) for undoped Co3O4 with increasing the doping percentage to (9%).
The physical separation between the LET associated with the ultimate relative biological effect (RBE) and the maximum LET in a proton or ion beam
Authors: Jones Bleddyn , Hill Mark A
Published: June 2020

Purpose: To identify the relative positions of the ultimate RBE, at a LET value of LETU (where the LET-RBE turnover point occurs independently of dose), and of the maximum LET (LETM) for a range of ions from protons to Iron ions. Methods: For a range of relativistic velocities (β), the kinetic energies, LET values and ranges for each ion are obtained using SRIM software. For protons and helium ions, the LET changes with β are plotted and LETM is compared with LETU. For all the ions studied the residual ranges of particles at LETU and LETM are subtracted to provide the physical separation (S) between LETU and LETM. Results: Graphical methods are used to show the above parameters for protons and helium ions. For all the ions studied, LETU occurs at kinetic energies which are higher than those at LETM, so the ultimate maximal RBE occurs proximal to the Bragg peak for individual particles and not beyond it, as is commonly supposed. The distance S, between LETU and LETM, appears to increase linearly with the atomic charge value Z. Conclusions: For the lighter elements, from protons to carbon ions, S is sufficiently small (less than the tolerance/accuracy of radiation treatments) and so will probably not influence therapeutic decisions or outcomes. For higher Z numbers such as Argon and Iron, larger S values of several centimetres occur, which may have implications not only in any proposed therapeutic beams but also at very low doses encountered in radiation protection where the few cells that are irradiated will typically be traversed by a single particle.
Minimum hardware requirements for hybrid quantum–classical DMFT
Authors: Jaderberg B , Agarwal A , Leonhardt K , Kiffner M , Jaksch D
Published: June 2020

We numerically emulate noisy intermediate-scale quantum (NISQ) devices and determine the minimal hardware requirements for two-site hybrid quantum–classical dynamical mean-field theory (DMFT). We develop a circuit recompilation algorithm which significantly reduces the number of quantum gates of the DMFT algorithm and find that the quantum–classical algorithm converges if the two-qubit gate fidelities are larger than 99%. The converged results agree with the exact solution within 10%, and perfect agreement within noise-induced error margins can be obtained for two-qubit gate fidelities exceeding 99.9%. By comparison, the quantum–classical algorithm without circuit recompilation requires a two-qubit gate fidelity of at least 99.999% to achieve perfect agreement with the exact solution. We thus find quantum–classical DMFT calculations can be run on the next generation of NISQ devices if combined with the recompilation techniques developed in this work.
A Dictionary of Film Studies
Authors: Kuhn Annette , Westwell Guy
Published: June 2020

Over 550 entries

This dictionary covers all aspects of its discipline as it is currently taught at undergraduate level. Offering exhaustive and authoritative coverage, this A-Z is written by experts in the field and covers terms, concepts, debates, and movements in film theory and criticism; national, international, and transnational cinemas; film history, movements, and genres; film industry organizations and practices; and key technical terms and concepts.

Since its first publication in 2012, the dictionary has been updated to incorporate over 40 new entries, including computer games and film, disability, ecocinema, identity, portmanteau film, Practice as Research, and film in Vietnam. Moreover, numerous revisions have been made to existing entries to account for developments in the discipline, and changes to film institutions more generally.
Research with older people in a world with COVID-19: identification of current and future priorities, challenges and opportunities
Authors: Richardson Sarah J , Carroll Camille B , Close Jacqueline , Gordon Adam L , O’Brien John , Quinn Terence J , Rochester Lynn , Sayer Avan A , Shenkin Susan D , van der Velde Nathalie , Woo Jean , Witham Miles D
Published: June 2020

Older people are disproportionately affected by the COVID-19 pandemic, which has had a profound impact on research as well as clinical service delivery. This commentary identifies key challenges and opportunities in continuing to conduct research with and for older people, both during and after the current pandemic. It shares opinions from responders to an international survey, a range of academic authors and opinions from specialist societies. Priorities in COVID-19 research include its specific presentation in older people, consequences for physical, cognitive and psychological health, treatments and vaccines, rehabilitation, supporting care homes more effectively, the impact of social distancing, lockdown policies and system reconfiguration to provide best health and social care for older people. COVID-19 research needs to be inclusive, particularly involving older people living with frailty, cognitive impairment or multimorbidity, and those living in care homes. Non-COVID-19 related research for older people remains of critical importance and must not be neglected in the rush to study the pandemic. Profound changes are required in the way that we design and deliver research for older people in a world where movement and face-to-face contact are restricted, but we also highlight new opportunities such as the ability to collaborate more widely and to design and deliver research efficiently at scale and speed.
Field Study of the Possible Effect of Parental Irradiation on the Germline of Children Born to Cleanup Workers and Evacuees of the Chornobyl Nuclear Accident
Authors: Bazyka Dimitry , Hatch Maureen , Gudzenko Natalia , Cahoon Elizabeth K , Drozdovitch Vladimir , Little Mark P , Chumak Vadim , Bakhanova Elena , Belyi David , Kryuchkov Victor , Golovanov Ivan , Mabuchi Kiyohiko , Illienko Iryna , Belayev Yuri , Bodelon Clara , Machiela Mitchell J , Hutchinson Amy , Yeager Meredith , de Gonzalez Amy Berrington , Chanock Stephen J
Published: June 2020

Although transgenerational effects of exposure to ionizing radiation have long been a concern, human research to date has been confined to studies of disease phenotypes in groups exposed to high doses and high dose rates, such as the Japanese atomic bomb survivors. Transgenerational effects of parental irradiation can be addressed using powerful new genomic technologies. In collaboration with the Ukrainian National Research Center for Radiation Medicine, the US National Cancer Institute, in 2014–2018, initiated a genomic alterations study among children born in selected regions of Ukraine to cleanup workers and/or evacuees exposed to low–dose-rate radiation after the 1986 Chornobyl (Chernobyl) nuclear accident. To investigate whether parental radiation exposure is associated with germline mutations and genomic alterations in the offspring, we are collecting biospecimens from father-mother-offspring constellations to study de novo mutations, minisatellite mutations, copy-number changes, structural variants, genomic insertions and deletions, methylation profiles, and telomere length. Genomic alterations are being examined in relation to parental gonadal dose, reconstructed using questionnaire and measurement data. Subjects are being recruited in exposure categories that will allow examination of parental origin, duration, and timing of exposure in relation to conception. Here we describe the study methodology and recruitment results and provide descriptive information on the first 150 families (mother-father-child(ren)) enrolled.
Archaeosporites rhyniensis gen. et sp. nov. (Glomeromycota, Archaeosporaceae) from the Lower Devonian Rhynie chert: a fungal lineage morphologically unchanged for more than 400 million years
Authors: Harper Carla J , Walker Christopher , Schwendemann Andrew B , Kerp Hans , Krings Michael
Published: June 2020

Background and Aims

Structurally preserved arbuscular mycorrhizas from the Lower Devonian Rhynie chert represent core fossil evidence of the evolutionary history of mycorrhizal systems. Moreover, Rhynie chert fossils of glomeromycotan propagules suggest that this lineage of arbuscular fungi was morphologically diverse by the Early Devonian; however, only a small fraction of this diversity has been formally described and critically evaluated.

Methods

Thin sections, previously prepared by grinding wafers of chert from the Rhynie beds, were studied by transmitted light microscopy. Fossils corresponding to the description of Archaeospora spp. occurred in 29 slides, and were measured, photographed and compared with modern-day species in that genus.

Key Results

Sessile propagules <85 µm in diameter, some still attached to a sporiferous saccule, were found in early land plant axes and the chert matrix; they developed, in a similar manner to extant Archaeospora, laterally or centrally within the saccule neck. Microscopic examination and comparison with extant fungi showed that, morphologically, the fossils share the characters used to circumscribe the genus Archaeospora (Glomeromycota; Archaeosporales; Archaeosporaceae).

Conclusions

The fossils can be assigned with confidence to the extant family Archaeosporaceae, but because molecular analysis is necessary to place organisms in these taxa to present-day genera and species, they are placed in a newly proposed fossil taxon, Archaeosporites rhyniensis.
Functional dissection of HGGT and HPT in barley vitamin E biosynthesis via CRISPR/Cas9-enabled genome editing
Authors: Zeng Zhanghui , Han Ning , Liu Cuicui , Buerte B , Zhou Chenlu , Chen Jianshu , Wang Mengyao , Zhang Yuhong , Tang Yawei , Zhu Muyuan , Wang Junhui , Yang Yinong , Bian Hongwu
Published: June 2020

Background and Aims

Vitamin E (tocochromanol) is a lipid-soluble antioxidant and an essential nutrient for human health. Among cereal crops, barley (Hordeum vulgare) contains a high level of vitamin E, which includes both tocopherols and tocotrienols. Although the vitamin E biosynthetic pathway has been characterized in dicots, such as Arabidopsis, which only accumulate tocopherols, knowledge regarding vitamin E biosynthesis in monocots is limited because of the lack of functional mutants. This study aimed to obtain gene knockout mutants to elucidate the genetic control of vitamin E composition in barley.

Methods

Targeted knockout mutations of HvHPT and HvHGGT in barley were created with CRISPR/Cas9-enabled genome editing. High-performance liquid chromatography (HPLC) was performed to analyse the content of tocochromanol isomers in transgene-free homozygous Hvhpt and Hvhggt mutants.

Key Results

Mutagenesis efficiency among T0 regenerated plantlets was 50–65 % as a result of two simultaneously expressed guide RNAs targeting each gene; most of the mutations were stably inherited by the next generation. The transgene-free homozygous mutants of Hvhpt and Hvhggt exhibited decreased grain size and weight, and the HvHGGT mutation led to a shrunken phenotype and significantly lower total starch content in grains. HPLC analysis revealed that targeted mutation of HvHPT significantly reduced the content of both tocopherols and tocotrienols, whereas mutations in HvHGGT completely blocked tocotrienol biosynthesis in barley grains. Transient overexpression of an HvHPT homologue in tobacco leaves significantly increased the production of γ- and δ-tocopherols, which may partly explain why targeted mutation of HvHPT in barley grains did not eliminate tocopherol production.

Conclusions

Our results functionally validated that HvHGGT is the only committed gene for the production of tocotrienols, whereas HvHPT is partly responsible for tocopherol biosynthesis in barley.
Specific mycorrhizal associations involving the same fungal taxa in common and threatened Caladenia (Orchidaceae): implications for conservation
Authors: Reiter Noushka , Phillips Ryan D , Swarts Nigel D , Wright Magali , Holmes Gareth , Sussmilch Frances C , Davis Belinda J , Whitehead Michael R , Linde Celeste C
Published: June 2020

Background and Aims

In orchid conservation, quantifying the specificity of mycorrhizal associations, and establishing which orchid species use the same fungal taxa, is important for sourcing suitable fungi for symbiotic propagation and selecting sites for conservation translocation. For Caladenia subgenus Calonema (Orchidaceae), which contains 58 threatened species, we ask the following questions. (1) How many taxa of Serendipita mycorrhizal fungi do threatened species of Caladenia associate with? (2) Do threatened Caladenia share orchid mycorrhizal fungi with common Caladenia? (3) How geographically widespread are mycorrhizal fungi associated with Caladenia?

Methods

Fungi were isolated from 127 Caladenia species followed by DNA sequencing of the internal transcibed spacer (ITS) sequence locus. We used a 4.1–6 % sequence divergence cut-off range to delimit Serendipita operational taxonomic units (OTUs). We conducted trials testing the ability of fungal isolates to support germination and plant growth. A total of 597 Serendipita isolates from Caladenia, collected from across the Australian continent, were used to estimate the geographic range of OTUs.

Key Results

Across the genus, Caladenia associated with ten OTUs of Serendipita (Serendipitaceae) mycorrhizal fungi. Specificity was high, with 19 of the 23 threatened Caladenia species sampled in detail associating solely with OTU A, which supported plants from germination to adulthood. The majority of populations of Caladenia associated with one OTU per site. Fungal sharing was extensive, with 62 of the 79 Caladenia sampled in subgenus Calonema associating with OTU A. Most Serendipita OTUs were geographically widespread.

Conclusions

Mycorrhizal fungi can be isolated from related common species to propagate threatened Caladenia. Because of high specificity of most Caladenia species, only small numbers of OTUs typically need to be considered for conservation translocation. When selecting translocation sites, the geographic range of the fungi is not a limiting factor, and using related Caladenia species to infer the presence of suitable fungal OTUs may be feasible.
Impairments of auditory scene analysis in posterior cortical atrophy
Authors: Hardy Chris J D , Yong Keir X X , Goll Johanna C , Crutch Sebastian J , Warren Jason D
Published: June 2020

Although posterior cortical atrophy is often regarded as the canonical ‘visual dementia’, auditory symptoms may also be salient in this disorder. Patients often report particular difficulty hearing in busy environments; however, the core cognitive process—parsing of the auditory environment (‘auditory scene analysis’)—has been poorly characterized. In this cross-sectional study, we used customized perceptual tasks to assess two generic cognitive operations underpinning auditory scene analysis—sound source segregation and sound event grouping—in a cohort of 21 patients with posterior cortical atrophy, referenced to 15 healthy age-matched individuals and 21 patients with typical Alzheimer’s disease. After adjusting for peripheral hearing function and performance on control tasks assessing perceptual and executive response demands, patients with posterior cortical atrophy performed significantly worse on both auditory scene analysis tasks relative to healthy controls and patients with typical Alzheimer’s disease (all P < 0.05). Our findings provide further evidence of central auditory dysfunction in posterior cortical atrophy, with implications for our pathophysiological understanding of Alzheimer syndromes as well as clinical diagnosis and management.
Genetic Deletion of TrpV1 and TrpA1 Does Not Alter Avoidance of or Patterns of Brainstem Activation to Citric Acid in Mice
Authors: Yu Tian , Wilson Courtney E , Stratford Jennifer M , Finger Thomas E
Published: June 2020

Exposure of the oral cavity to acidic solutions evokes not only a sensation of sour, but also of sharp or tangy. Acidic substances potentially stimulate both taste buds and acid-sensitive mucosal free nerve endings. Mice lacking taste function (P2X2/P2X3 double-KO mice) refuse acidic solutions similar to wildtype (WT) mice and intraoral infusion of acidic solutions in these KO animals evokes substantial c-Fos activity within orosensory trigeminal nuclei as well as of the nucleus of the solitary tract (nTS) (Stratford, Thompson, et al. 2017). This residual acid-evoked, non-taste activity includes areas that receive inputs from trigeminal and glossopharyngeal peptidergic (CGRP-containing) nerve fibers that express TrpA1 and TrpV1 both of which are activated by low pH. We compared avoidance responses in WT and TrpA1/V1 double-KO (TRPA1/V1Dbl−/−) mice in brief-access behavioral assay (lickometer) to 1, 3, 10, and 30 mM citric acid, along with 100 µM SC45647 and H2O. Both WT and TRPA1/V1Dbl−/− show similar avoidance, including to higher concentrations of citric acid (10 and 30 mM; pH 2.62 and pH 2.36, respectively), indicating that neither TrpA1 nor TrpV1 is necessary for the acid-avoidance behavior in animals with an intact taste system. Similarly, induction of c-Fos in the nTS and dorsomedial spinal trigeminal nucleus was similar in the WT and TRPA1/V1Dbl−/− animals. Taken together these results suggest non-TrpV1 and non-TrpA1 receptors underlie the residual responses to acids in mice lacking taste function.
Single-cell RNA sequencing reveals cell type- and artery type-specific vascular remodelling in male spontaneously hypertensive rats
Authors: Cheng Jun , Gu Wenduo , Lan Ting , Deng Jiacheng , Ni Zhichao , Zhang Zhongyi , Hu Yanhua , Sun Xiaolei , Yang Yan , Xu Qingbo
Published: June 2020

Aims

Hypertension is a major risk factor for cardiovascular diseases. However, vascular remodelling, a hallmark of hypertension, has not been systematically characterized yet. We described systematic vascular remodelling, especially the artery type- and cell type-specific changes, in hypertension using spontaneously hypertensive rats (SHRs).

Methods and results

Single-cell RNA sequencing was used to depict the cell atlas of mesenteric artery (MA) and aortic artery (AA) from SHRs. More than 20 000 cells were included in the analysis. The number of immune cells more than doubled in aortic aorta in SHRs compared to Wistar Kyoto controls, whereas an expansion of MA mesenchymal stromal cells (MSCs) was observed in SHRs. Comparison of corresponding artery types and cell types identified in integrated datasets unravels dysregulated genes specific for artery types and cell types. Intersection of dysregulated genes with curated gene sets including cytokines, growth factors, extracellular matrix (ECM), receptors, etc. revealed vascular remodelling events involving cell–cell interaction and ECM re-organization. Particularly, AA remodelling encompasses upregulated cytokine genes in smooth muscle cells, endothelial cells, and especially MSCs, whereas in MA, change of genes involving the contractile machinery and downregulation of ECM-related genes were more prominent. Macrophages and T cells within the aorta demonstrated significant dysregulation of cellular interaction with vascular cells.

Conclusion

Our findings provide the first cell landscape of resistant and conductive arteries in hypertensive animal models. Moreover, it also offers a systematic characterization of the dysregulated gene profiles with unbiased, artery type-specific and cell type-specific manners during hypertensive vascular remodelling.
Social Status Concerns and the Political Economy of Publicly Provided Private Goods
Authors: Friedrichsen Jana , König Tobias , Lausen Tobias
Published: June 2020

We analyse the political economy of the public provision of private goods when individuals care about their social status. Status concerns motivate richer individuals to vote for the public provision of goods they themselves buy in markets: a higher provision level attracts more individuals to the public sector, enhancing the social exclusivity of market purchases. Majority voting may lead to a public provision that only a minority of citizens use. Users in the public sector may enjoy better provision than users in the private system. We characterise the coalitions that can prevail in a political equilibrium.
P518Inappropriate shocks in atrial fibrillation patients: are they really deleterious?
Authors: Marinheiro R , Parreira L , Amador P , Mesquita D , Farinha J , Fonseca M , Esteves A , Ferreira J , Lopes C , Caria R
Published: June 2020

Introduction

Data suggest inappropriate defibrillator shocks are associated with a higher risk of all-cause mortality, particularly those delivered for atrial fibrillation (AF). However, the impact of inappropriate shocks has not been studied specifically in a population with AF.

Aims

to determine if AF-triggered inappropriate shocks are associated with long- term mortality in patients with AF and defibrillators implanted for primary prevention.

Methods

Retrospective single-center study. We analyzed all patients with defibrillators implanted for primary prevention in whom AF was diagnosed until the end of 2017. The cause of inappropriate shocks was evaluated by analysis of the stored intracardiac electrogram. Basal characteristics, cardiovascular risk factors, left ventricle ejection fraction, heart failure etiology (ischemic and non-ischemic), kidney function (creatinine) and medication were evaluated. Death was assessed during the follow-up.

Results

We studied 177 patients [median age 66 years (IQR 59-71); 82% male], with defibrillators and AF. AF was diagnosed before defibrillator implantation in 131 patients (74%) and after the implantation in the remaining 46 (26%). Inappropriate shocks occurred in 31 patients and 24 (14%) were caused by AF with rapid ventricular response: 13 patients with previously diagnosed AF and 11 with new-onset AF. During a median follow-up of 65 (IQR: 36-104) months, 74 patients died. Multivariate Cox-regression analysis demonstrated inappropriate shocks caused by AF were not independently related with death (adjusted HR 0.53; CI 0.23-1.23, p = 0.14). Kaplan-Meier survival curve demonstrated patients with AF-triggered inappropriate shocks had a better survival comparing to those with AF but without inappropriate shocks (logrank, p = 0.03) (figure).

Conclusions

In this group of AF patients, inappropriate shocks caused by AF did not increase the risk of death. Instead, these patients had a better survival comparing to those with AF but no shocks, probably due to a re-evaluation of the patient´s status and subsequent closer medical monitoring, strictly control of symptoms and optimization of drug treatment. These results demonstrate that inappropriate shocks are probably not deleterious per si through a direct mechanism.

Abstract Figure. Kaplan-Meier survival curve
P543Cardiac resynchronization therapy in left ventricular non-compaction: long-term results in a series of 40 patients
Authors: Radu D A , Iorgulescu C N , Bogdan S N , Deaconu A I , Badiul A , Cojocaru C , Vatasescu R G
Published: June 2020

Background

Left ventricular non-compaction (LVNC) is a structural cardiomyopathy (SC) with a high probability of LV systolic dysfunction. Left bundle branch block (LBBB) frequently occurs in SCs.

Purpose

We sought to analyse the evolution of LVNC-CRT (LC) patients in general and compare it with the non-LVNC-CRT group (nLC).

Methods

We analysed 40 patients with contrast-MRI documented LVNC (concomitant positive Petersen and Jacquier criteria) implanted with CRT devices in CEHB. The follow-up included 7 hospital visits for each patient (between baseline and 3 years). Demographics, risk factors, usual serum levels, pre-procedural planning factors, clinical, ECG, TTE and biochemical markers were recorded. Statistical analysis was performed using software. Notable differences were reported as either p-values from crosstabs (discrete) or mean differences, p-values and confidence intervals from t-tests (continuous). A p-value of .05 was chosen for statistical significance (SS).

Results

Subjects in LC were younger (-7.52 ys; <.000; (-3.617;-11.440)), with no sex predominance, more obese (45.9 vs. 28.3%; <0.24) and had less ischaemic disease (17.9 vs. 39.7%; <.007). LC implants were usually CRT-Ds (91 vs. 49.5%; <.000) and more frequently MPP-ready (35.8 vs. 8.4%; <.000). At baseline, sinus rhythm was predominant in LC (97.4 vs. 79.8%; <.007) and permitted frequent use of optimal fusion CRT (75.5 vs. 46.6%; <.002). Although initial LVEFs were similar, LCs had much larger EDVs (+48.91 ml; <.020; (+7.705;+90.124)) and ESVs (+34.91; <.05; (+1.657;+71.478)). After an initial encouraging ⁓ 1 year evolution the LC-CRT group crashed its performance in terms of both LVEF and volumes. Thus, at 1 year follow-up, when compared to nLCs, LVEFs were far lower (-22.02%; <.000; (-32.29;-11.76)) while EDVs and ESVs much higher – (+70.8 ml; <.037; (+49.27;+ 189.65)) and (+100.13; <.039; (+5.25;+195)) respectively – in LCs in spite of similarly corrected dyssynchrony. The mean mitral regurgitation (MR) degree at 1 year was much higher in LCs (+1.8 classes; <.002; (+0.69;+2.97)) certainly contributing to the poor results. The cumulated super-responder/responder (SR/R) rates were constantly lower and decreasing at both 1 year (37.5 vs. 72.4; <.040) and 2 years of follow-up (10.1 vs. 80%; NS).

Conclusions

CRT candidates with LVNC are significantly more severe at the time of implant. After an initial short-term improvement (probably due to acute correction of dyssynchrony) most patients fail to respond in the long term. Severe dilation with important secondary MR probably plays an important role.
P1004Atrial fibrillation during acute myocardial infarction : a prospective multicenter study
Authors: Grigoryan S , Hazarapetyan L G , Ter-Markaryan A A , Drampyan M F
Published: June 2020

New-onset atrial fibrillation (AF) frequently complicates acute myocardial infarction (AMI) and is associated with higher in-hospital and 1-year mortality, particularly in patients with ST-segment elevation AMI. In this clinical setting the occurrence of AF is of particular importance since irregular ventricular rates during AF may cause further impairment of the coronary circulation and left ventricular function in addition to the adverse consequences of neuro-hormonal activation. However, incidence and risk factors contributing to the occurrence of AF in AMI are still not well-known. The purpose of this study is to evaluate prospectively some risk factors contributing the incidence of AF in the setting of AMI.

Methods

This was a three-center prospective study, conducted in the coronary care unit of our medical center during the period of January 2017 to June 2018. This study included 976 patients with acute MI of different localization. AF was found in 82 patients of whom 68 experienced this arrhythmia anew. Onset, duration and mode of termination of AF, clinical and risk factors associated with its presentation and its relation with patient outcome were evaluated. Anamnesis, clinical and functional state of the heart (according to the results of instrumental and laboratory data) was studied in all patients. The data was analyzed for statistical significance using multivariate analyses by SPSS 16.

Results

  The obtained results showed that in acute MI AF was registered in 9.4% of patients, among which new episodes of AF have been identified in 82.9% of patients. All the patients who developed AF after AMI were more than 60 years of age. Moreover, 68% of patients with AF have arterial hypertension, 27% - diabetes mellitus and 67% patients have higher heart rate. There is a relationship between developed AF and other supraventricular arrhythmias in the past history.  In 62% of patients with AF, anterior MI was detected and accompanied by more severe hemodynamic disorders. Multivariate analyses showed that AF correlated weakly with age (r = 0.249) and strongly with left atrial diameter (r = 0.478) and left ventricular dysfunction (r = 0.419) especially with higher Killip class.

Conclusions

The results of the present study revealed that in the presence of identified certain risk factors in patients with acute MI, AF may develop. There is the link between identified risk factors and the occurrence of AF
63Effects of exercise-based cardiac rehabilitation and detraining on exercise capacity and cardiac function in patients with atrial fibrillation: a randomized controlled trial with 1-year follow-up
Authors: Kim S , Han D , Lee S , Wee S , Oh M , Jeong I
Published: June 2020

Introduction

We aimed to determine whether maximal exercise capacity, left ventricular function, and quality of life (QoL) scores are sustained in patients with atrial fibrillation (AF) after termination of training following exercise-based cardiac rehabilitation (ECR).

Methods

In a prospective study, 58 patients with AF (age, 62 ± 7 years) were randomized into an exercise training group for 12 months (ECR, n = 13), a group with 6-month detraining after a 6-month exercise training (DT, n = 15), and a medical treatment only group (MT, n = 30). For exercise training, cycling on a bicycle ergometer was performed in the DT and ECR groups 3 times a week for 6 and 12 months, respectively. Each session started with a 10-minute warm-up at 60%–70% of the maximal heart rate (HRpeak), followed by four 4-minute intervals at 80%–90% of the HRpeak, with 3 minutes of active recovery at 60%–70% of the HRpeak between intervals, ending with a 5-minute cool-down period. Peak exercise oxygen consumption (Vo2), left ventricular function, plasma lipid level, N-terminal pro B-type natriuretic peptide level, and QoL score were measured at baseline, after 6 months of training, and after additional 6 months of continuous training or detraining follow-up assessments.

Results

Six months of exercise training increased the peak Vo2 (ECR: 28.2 ± 7.0 ml/[kg·min] and DT: 28.0 ± 8.3 ml/[kg·min] vs. MT: 23.0 ± 5.2 ml/[kg·min], p= 0.047) and QoL scores (36-Item Short-form Health Survey) and decreased the total cholesterol level (ECR: 146.8 ± 43.8 mg/dl and DT: 140.6 ± 22.4 vs. MT: 182 ± 44.2 mg/dl, p = 0.008). Detraining resulted in an increase in QoL score and a decrease in total cholesterol level (ECR: 142.8 ± 21.4 mg/dl and DT: 151.8 ± 39.8 vs. MT: 176.8 ± 34.2 mg/dl, p = 0.017). However, the exercise training-induced increase in peak Vo2 reverted to the baseline level after detraining (ECR: 27.1 ± 5.1 ml/kg/min vs. DT: 24.4 ± 7.2 ml/[kg·min] and MT: 21.5 ± 4.86 ml/[kg·min], p = 0.017). The resting left ventricular systolic and diastolic functions were not significantly different, with no inter-group difference after 6 months of training and 6 months of continuous training or detraining.

Conclusions

As the QoL scores are maintained despite peak Vo2 being lowered by detraining after an exercise training period in patients with AF, physicians should encourage patients’ participation in a continuous exercise program to sustain the improvement in both the QoL score and peak Vo2 with exercise training. Further studies with larger sample sizes are needed to observe the long-term effects of exercise training and detraining.
P425Single procedure pace and ablate. evaluation of efficacy and safety comparing three different vascular routes
Authors: Abbas M , Whittaker L , Chapman M , Thornley A R , Towmey D , James S , Bates M
Published: June 2020

Funding Acknowledgements

No financial support for this study

Introduction

Permanent pacemaker implantation combined with AVN ablation is a well-established treatment for rate control in patients with atrial fibrillation refractory to medical therapy. At the same sitting, this has been achieved in a single procedure via the subclavian vein (SCV) for both pacemaker implantation and AVN ablation, by pacemaker implantation via the SCV with femoral access for AVN ablation or by using the femoral vein (FV) for leadless pacemaker implantation and AVN ablation with a coaxial single-puncture technique.

We evaluated all combined procedures (pacemaker implantation and AVN ablation at the same sitting) performed in a single centre over 9 years comparing clinical outcomes, complications rates and procedure times.

Statistical methods: 

Continuous variables are described as mean ± standard deviation (SD), and statistical differences between groups were evaluated by one-way ANOVA. A X2 test was used for categorical variables, with Fisher’s exact test for any field where the expected frequency was ≤5 with pvalue < 0.05 considered as statistically significant. The statistical analysis was performed using SPSS software package. 

Results

 

141 patients underwent AVN ablation at our institution as part of a ‘pace and ablate’ single procedure strategy between 14/2/11 and 10/6/19. 61 patients had a combined procedure via the SCV, 66 patients had pacemaker implanted via the SCV and AVN ablation via the FV in the same sitting and 14 patients had leadless pacemaker (Micra) implantation and AVN ablation via the FV. Our findings suggest that the fluoroscopy time as well as the total catheter laboratory time were much less in the Micra group compared to the other groups. In the conventional pacemaker groups (group 1 and 2), the fluoroscopy time was not statistically different between the two. There was a trend towards acute procedural failure, switching to another access as well as a higher complication rate in the SCV group, however this has not reached statistical significance. 

Conclusion

 

Our early data suggests that pacemaker implantation and AVN ablation with a coaxial single femoral vein puncture technique is safe and takes less fluoroscopy time as well as total laboratory time.

Procedural outcomes All (n = 141) Group 1: SCV (n = 61) Group 2: FV (n = 66) Group 3: Micra (n = 14) P-value Total cath-lab time (mins) 113.1 ± 40.4 106.2 ± 37.2 125.7 ± 42.5 86.9 ± 23.1 0.001 Total fluoroscopy time (mins) 8.8 ± 7.6 11 ± 7.8 7.7 ± 7.6 4.5 ± 3 0.0001 Acute procedural failure, n (%) 9 (6.4) 7 (11.5) 2 (3) 0 (0) **0.6 Complications, n (%) 7 (4.9) 5 (8.2) 2 (3) 0 (0) **0.62 **Fisher"s exact test applied to analysis of Micra VS Other methods
P1080Magnetic resonance imaging after electrical cardioversion of recent-onset atrial fibrillation in anticoagulant-naive patients - a study exploring clinically silent cerebral lesions
Authors: Arvanitis P , Johansson A K , Frick M , Malmborg H , Larsson E M , Blomstrom Lundqvist C
Published: June 2020

Funding Acknowledgements

Unrestricted grants from the Swedish Heart-Lung Foundation, the Swedish Research Council, Correvio International Sárl (CH) and Selanders stiftelse

Background

Patients with atrial fibrillation (AF) have a high incidence of cognitive impairment, which may be related to clinically silent microembolism causing cerebral infarctions.

Purpose

To explore the occurrence and timing of silent brain lesions following electrical cardioversion (CV) of recent onset AF in anticoagulant-naïve patients and to further study related effects on cognitive function and biomarkers of cerebral damage, S100b.

Methods

Patients with AF duration < 48 hours were prospectively included. Brain magnetic resonance imaging (MRI) and S100b, were obtained prior, after and 7-10 days following CV. Trail making tests (TMT-A and TMT-B) and their difference, ΔΤΜΤ, were assessed prior to CV, 7-10 days and 30 days after CV.

Results

Forty-three patients (84% males) with mean CHA2DS2-VASc score 0.6 ± 0.7 were included. Sequential MRI, including diffusion weighted scans, showed no new brain lesions after CV.

Chronic white matter hyperintensities (WMH) were present at baseline in 21/43 (49%) patients. By partitioning the study population into four major groups according to the extend of WMH (Fazekas score 0 or ≥ 1) and the presence or absence of TE risk factors (CHA2DS2-VASc score 0 or ≥ 1), the TE risk as defined by CHA2DS2-VASc score ≥ 1, was associated with a higher incidence of WMH, Pearson χ2(1,N = 43)=3.95, p = 0.047.

The S100b (µg/l) levels increased significantly from baseline, (mean ± SD) 0.0472 ± 0.0182 to 0.0551 ± 0.0185 after CV, p = 0.001 and then decreased 7-10 days after CV to 0.0450 ± 0.0186, p < 0.001. Subgroup analysis according to the presence of at least one TE risk factor as defined by CHA2DS2-VASc score showed that statistical significance of repeated measures ANOVA was maintained; for patients with no risk factors F (2,30)=12.59, p < 0.001 and for patients with CHA2DS2-VASc score ≥1 F(2,36)=4.43, p < 0.019.

Consecutive TMT scores improved successively after CV, being statistically and clinically significant for TMT-B (p < 0.01) and ΔΤΜΤ (p = 0.005) between 7-10 days and 30 days after CV (Reliable Change Index >1.96).

Conclusion

New brain lesions could not be detected on MRI after CV, but the high incidence of white matter hyperintensities and the transient increase in S100b may indicate transient or minor brain damage undetectable by MRI thus heightening the need to reevaluate thromboembolic risk prior to CV even in low risk patients.

Abstract Figure. S100b_TMT
Examining Senior Drivers’ Attitudes Toward Advanced Driver Assistance Systems After Naturalistic Exposure
Authors: Liang Dan , Lau Nathan , Baker Stephanie A , Antin Jonathan F
Published: June 2020

Background and Objectives

The increasing number of senior drivers may introduce new road risks due to age-related declines in physical and cognitive abilities. Advanced driver assistance systems (ADAS) have been proposed as solutions to minimize age-related declines, thereby increasing both senior safety and mobility. This study examined factors that influence seniors’ attitudes toward adopting ADAS after significant exposure to the technology in naturalistic settings.

Research Design and Methods

This study recruited 18 senior drivers aged 70–79 to drive vehicles equipped with ADAS for 6 weeks in their own environments. Afterward, each participant was enrolled in 1 of the 3 focus group sessions to discuss their changes in attitude toward ADAS based on their driving experiences. We applied structural topic modeling (STM) on the focus group transcripts to reveal key topics deemed important to seniors.

Results

STM revealed 5 topics of importance for seniors. In order of prevalence, these were (i) safety, (ii) confidence concerning ADAS, (iii) ADAS functionality, (iv) user interface/usability, and (v) non-ADAS–related features. Based on topics and associated keywords, seniors perceived safety improvement with ADAS but expressed concerns about its limitations in coping with adverse driving conditions. Experience and training were suggested for improving seniors’ confidence in ADAS. Blind spot alert and adaptive cruise control received the most discussion regarding perceived safety and comfort.

Discussion and Implications

This study indicated that promoting road safety for senior drivers through ADAS is feasible. Acceptance and appropriate use of ADAS may be supported through intuitive and senior-friendly user interfaces, in-depth training programs, and owner’s manuals specifically designed and tested for senior drivers.
Short-term outcome of the intuity rapid deployment prosthesis: a systematic review and meta-analysis
Authors: Klop Idserd David Gérard , Kougioumtzoglou Athiná M , Kloppenburg Geoffrey T L , van Putte Bart P , Sprangers Mirjam A G , Klein Patrick , Nieuwkerk Pythia T
Published: June 2020

OBJECTIVES

Limited access aortic valve replacement is an alternative approach for the treatment of calcified aortic valve disease. To facilitate limited access aortic valve replacement, rapid deployment valve prostheses have been developed aiming to reduce surgical impact. This systematic review gives an overview of current literature regarding the INTUITY or INTUITY Elite rapid deployment biological valve prosthesis.

Methods

Cochrane, Embase and MEDLINE were searched to identify relevant studies. All studies reporting on patients who underwent isolated or combined surgical aortic valve replacement with the INTUITY or INTUITY Elite valve prosthesis were considered eligible. Primary end points were technical success rate, 30-day mortality, cerebrovascular accident, paravalvular leak and permanent pacemaker implantation. Secondary end points included procedural data such as aortic cross-clamping time, cardiopulmonary bypass time and procedural approach.

Results

A total of 16 articles fulfilled the inclusion and exclusion criteria and comprised 4.184 patients. Thirty-day mortality was 2.7% (1.9–3.7%), cerebrovascular accident 2.6% (1.4–4.7%), permanent pacemaker implantation 7.9% (6.6–9.5%) and severe postoperative paravalvular leak requiring a reintervention 3.3% (1.7–6.1%). Technical success rate varied between 93.9% and 100%. Conventional median sternotomy was most commonly performed, ranging from 21.7% to 89.6%. Upper hemi-sternotomy was performed more often than anterior right thoracotomy, ranging from 10.4% to 63.3% and 2.2% to 26.1%. The mean transvalvular pressure gradient ranged between 9.0 and 10.3 mmHg at 1 year postoperatively.

Conclusions

This review demonstrates that the technical success rate of the INTUITY or INTUITY Elite rapid deployment valve system is high, also in limited access aortic valve replacement. Mortality and cerebrovascular accident rates are low, but the need for postoperative permanent pacemaker implantation and reintervention rate for paravalvular leakage is increased.