bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of discharge energy and nano Al2O3on μED milling of Inconel 718
Authors: B Elumalai , S Gowri , P Hariharan , KV Arun Pillai 
Published: October 2021

AbstractMicro EDM is a well-recognized machining process for complex and precise three-dimensional micro features. However, the disadvantages are high machining time, poor surface finish, and a thick recast layer that restricts the wide establishments. Powder mixed EDM (PMEDM) is a recent advancement in the EDM process that enhances the sparking frequency and inter-electrode gap. This paper presents the effect of Al2O3nanopowder on micro ED milling of Inconel 718 at chosen levels of discharge energy (3.2μJ to 7.2μJ, 32μJ to 72μJ and 320μJ to 720μJ). To understand the dynamics of the process, comprehensive experimental research was carried out using a full factorial design with 60 experiments. Material removal rate, tool wear rate, and surface finish were evaluated. The surface topography and material migration to the machined surface was also studied. The results showed significant improvement of 157%, 20%, and 21% in MRR, TWR, and surface roughness respectively in nanopowder mixed micro-EDM when compared with conventional micro-EDM. The addition of Al2O3nanopowder reduced crater size in all three discharge energy ranges and reduced carbon deposition on the machined surface.
Generative adversarial networks improve interior computed tomography angiography reconstruction
Authors: Ketola Juuso H J , Heino Helinä , Juntunen Mikael A K , Nieminen Miika T , Siltanen Samuli , Inkinen Satu I 
Published: October 2021

Abstract
In interior computed tomography (CT), the x-ray beam is collimated to a limited field-of-view (FOV) (e.g. the volume of the heart) to decrease exposure to adjacent organs, but the resulting image has a severe truncation artifact when reconstructed with traditional filtered back-projection (FBP) type algorithms. In some examinations, such as cardiac or dentomaxillofacial imaging, interior CT could be used to achieve further dose reductions. In this work, we describe a deep learning (DL) method to obtain artifact-free images from interior CT angiography. Our method employs the Pix2Pix generative adversarial network (GAN) in a two-stage process: (1) An extended sinogram is computed from a truncated sinogram with one GAN model, and (2) the FBP reconstruction obtained from that extended sinogram is used as an input to another GAN model that improves the quality of the interior reconstruction. Our double GAN (DGAN) model was trained with 10 000 truncated sinograms simulated from real computed tomography angiography slice images. Truncated sinograms (input) were used with original slice images (target) in training to yield an improved reconstruction (output). DGAN performance was compared with the adaptive de-truncation method, total variation regularization, and two reference DL methods: FBPConvNet, and U-Net-based sinogram extension (ES-UNet). Our DGAN method and ES-UNet yielded the best root-mean-squared error (RMSE) (0.03 ± 0.01), and structural similarity index (SSIM) (0.92 ± 0.02) values, and reference DL methods also yielded good results. Furthermore, we performed an extended FOV analysis by increasing the reconstruction area by 10% and 20%. In both cases, the DGAN approach yielded best results at RMSE (0.03 ± 0.01 and 0.04 ± 0.01 for the 10% and 20% cases, respectively), peak signal-to-noise ratio (PSNR) (30.5 ± 2.6 dB and 28.6 ± 2.6 dB), and SSIM (0.90 ± 0.02 and 0.87 ± 0.02). In conclusion, our method was able to not only reconstruct the interior region with improved image quality, but also extend the reconstructed FOV by 20%.
Computer simulation of key structural parameters for enhanced infrared absorption with Au nano-array
Authors: Mitobe Daichi , Ohshima Taku , Suzuki Yushi 
Published: October 2021

Abstract
The optical constants of thin films with nanoscale structures, such as metamaterials and nanostructured films used in surface enhanced infrared absorption (SEIRA), are represented by effective medium approximation (EMA). In a representative EMA, the effective permittivity is determined by parameters such as the volume filling factor (F). In a metal square column array modeled on an evaporated film, the effective permittivity is determined by the gap size/particle size ratio (f). However, f is also expressed as a function of F. For this study, we simulated the SEIRA spectrum using a model in which f and F were varied independently to investigate which was the most important parameter in the square column array. The results showed all the simulations performed, results showed that the gap size/particle size ratio (f) is an important parameter for the increase in SEIRA in the square column array. This study has led to new discoveries that support elucidation of the SEIRA enhancement mechanism.
The Postliberal Aesthetic; or, How Can Literary Criticism Help Unsettle America’s Polarization?
Authors: Voelz Johannes 
Published: October 2021

Abstract
This essay interprets the present moment as marked by democratic crisis and assigns to American literary criticism the task of responding to it. While American democracy faces multiple crises, the essay contends that current levels of polarization make it impossible to effectively address any of them. In this situation, literary studies confronts a dual challenge: it must, first, come to terms with its own contribution to the dynamics of polarization and, second, consider whether it can help undo it. Adopting a cultural–sociological perspective, the essay identifies literary studies as an institution that consolidates the politico-cultural identity of the “new middle class” and contributes to the culturalization of politics underlying contemporary polarization. However, the essay contends, American literary studies has the capacity to help revive democratic culture if it nurtures reading practices that unsettle fixed identities. To that end, the essay singles out various recent theories of reading whose democratic potential is grounded in their shared premise that literature is a communicative act. In interpreting these models of criticism as a potential way out of the malaise of polarization, the essay makes a call to revisit, reevaluate, and reformulate the tradition of liberalism.
Prognostic factors in patients with acute myocardial infarction underwent extracorporeal membrane oxygenation in hospital or out-of-hospital cardiac arrest
Authors: Morimoto R , Kida H , Tachibana K , Watanabe T , Yamada T 
Published: October 2021

Abstract

Background
Patients with acute myocardial infarction (AMI) who require extracorporeal membrane oxygenation (ECMO) have worse outcomes than those who do not, and patients with AMI with out-of-hospital cardiac arrest (OHCA) also have worse outcomes than those without OHCA. However, there have been still unclear points regarding the prognostic factors of AMI patients who underwent ECMO with or without OHCA. The aim of this study was to investigate the prognostic factors of AMI patients who underwent ECMO with and without OHCA, respectively.

Methods/Results
Ninety-eight consecutive patients (age:67±11 years, male:83.7%) who underwent ECMO for AMI were enrolled from November 2008 to December 2020. The primary endpoint was in-hospital mortality within 30-day, and we investigated the risk factors associated with 30-day mortality in AMI patients underwent ECMO with or without OHCA, respectively. In the group with OHCA (n=47), 30-day death occurred in 22 patients (47%). BMI, lactate and serum creatinine levels after the introduction of ECMO were significantly greater in patients with than without 30-day death (27.0±5.2 vs 21.0±2.9 kg/m2, p&lt;0.001, 12.1±4.3 vs 7.5±3.6 mmol/L, p&lt;0.001, 1.68±1.24 vs 1.41±1.07 mg/dL, p=0.039, respectively). The multivariate regression analysis showed that lactate level was independently associated with the poor outcome (Odds ratio: 1.32, 95% CI: 1.11–1.57, p&lt;0.001). ROC curve analysis showed that the cut-off values: 7.8mmol/L of lactate had moderate accuracy to predict 30-day mortality (sensitivity:76%, specificity:86%, AUC:0.81). In the group without OHCA (n=51), 30-day death occurred in 20 patients (39%). The frequency of ventricular tachycardia / fibrillation (VT/VF) at initiation of ECMO was significantly higher (61.3% vs 25.0%, p=0.021), the frequency of mechanical complication was significantly lower (6.5% vs 30.0%, p=0.045) in patients without 30-day death than with 30-day death. The multivariate regression analysis showed that VT/VF at initiation of ECMO was independently associated with good outcome (Odds ratio: 0.21, 95% CI: 0.06–0.73, p=0.01).

Conclusions
With OHCA, increased lactate was the risk factor that was significantly associated with poor outcome in AMI patients underwent ECMO. Without OHCA, AMI patients who underwent ECMO due to rhythm trouble such as VT/VF had a good outcome. ECMO patients with AMI may have different prognostic factors with or without OHCA.

Funding Acknowledgement
Type of funding sources: None. Patient characteristics
Frailty assessment in an unselected population admitted to an intensive cardiac care unit
Authors: Campanile A , Procaccini C , Dell' Aquila F , Tedeschi M , Rispoli A , Sorrentino R , Ravera A 
Published: October 2021

Abstract

Background
Although interest in frailty has expanded among cardiology experts over the past 2 decades, its integration, as part of cardiovascular disease management, is still lacking, above all in the acute cardiac care setting. The Clinical Frailty Scale (CFS) is a brief guided tool to assess frailty in hospital settings without specialist equipment.

Purpose
Our objective was to test the performance of the CFS in an older, unselected population, admitted to an Intensive Cardiac Care Unit (ICCU) during the year 2019.

Methods
The study sample included 431 patients ≥65 years old, admitted to an ICCU of a tertiary cardiac center in Italy. The CFS ranged from “very fit: 1” to “terminally ill: 9”, but it was considered present at a score ≥5. Our primary endpoint was defined by a combination of severe complications requiring critical care and in-hospital death. The data were collected from the hospital discharge summary and the electronic chart records.

Results
158 patients (36.7%) were frail. These individuals had greater comorbidity and higher in-hospital mortality (Table 1). After a multivariable logistic regression analysis, 4 predictors were identified: signs of congestive heart failure (OR: 8.51, 95% Confidence Interval-CI: 4.63–14.6; p&lt;0,001), systolic blood pressure (OR per 1 mmHg increasing: 0.98, 95% CI: 0.97–0.99; p&lt;0,001), smoking habit (OR: 0.49, 95% CI: 0.22–1.11; p=0.09) and the CFS ≥5 (OR: 1.86, 95% CI: 1.08–3.23: p=0,026).

Conclusions
The CFS is a simple guided frailty tool that may enhance outcome prediction in the acute cardiac care setting. These findings merit evaluation in larger cohorts of unselected patients.

Funding Acknowledgement
Type of funding sources: None.
Role of conduit volume as a compensatory mechanism to left atrial dysfunction in severe aortic stenosis
Authors: Migliore R A , Adaniya M E , Barranco M A , Miramont G 
Published: October 2021

Abstract

Background
Left atrial (LA) function has a central role in maintaining optimal cardiac output despite impaired left ventricular (LV) diastolic function through atrial reservoir, conduit and contractile functions. In normal subjects, the contribution of LA volume (conduit and contractile) to LV filling volume is approximately 60–70% and the rest is completed by the conduit volume (CV) defined as the blood flow from pulmonary veins to LV during passive emptying that does not produce change in atrial volume. As LV filling pressures progressively increase, the limits of preload reserve are reached and LA serves predominantly as a conduit with increase in CV. Severe aortic stenosis is characterized by diastolic dysfunction (DD) in early stages of the disease and LA dysfunction in more advanced stages.

Purpose
The aim of the study was to analyze the role of CV as a compensatory mechanism to complete LV filling volume in presence of atrial dysfunction.

Methods
210 patients (p) (age 69±11 years, 48% female) with severe aortic stenosis (aortic valve area index 0.37±0.12 cm2/m2) were studied with Doppler echocardiography. LA function were evaluated by LA (total) emptying fraction (LAEF) as the difference between maximum (Mx) (include conduit and contractile phases) and minimum (Mn) volumes/Mx volume x 100 and peak LA strain. The contribution of CV to SV was estimated as a percentage of SV (CV%): SV − (LA Mx − Mn volume)/SV x 100. LA volumes, SV and left ventricular ejection fraction (LVEF) were calculated by Simpson method. Grade of DD was classified according to ASE/EACVI recommendation and p were divided in 3 groups: DD grade I (98 p), DD grade II (74 p) and DD grade III (38 p).

Results
CV% were negatively related to LAEF (r=−0.57, p&lt;0.0001) and peak LA strain (r=−0.38, p&lt;0.001) and directly to the grade of DD (r=0.35, p&lt;0.001). LVEF correlated with LAEF (r=0.57, p&lt;0.0001) and CV% (r=−033, p&lt;0.001). In group DD grade III SV was maintained by increase in CV% despite significant decrease in LAEF and peak LA strain.

Conclusion
LA dysfunction expressed as a decreased in LAEF and LA strain correlated with an increase in contribution of CV to SV (CV%). In patients with AS, as the DD progress, SV is maintained by increase in CV as a compensatory mechanism to LA dysfunction.

Funding Acknowledgement
Type of funding sources: None. Table
Evaluation of functional mitral regurgitation profile in a real-world cohort of heart failure patients and the referral rate of these patients
Authors: Presume J , Lopes P , Albuquerque F , Freitas P , Trabulo M , Joao Andrade M , Mendes M , Ribeiras R 
Published: October 2021

Abstract

Introduction
Patients with heart failure and reduced ejection fraction (HFrEF) frequently have significant functional mitral regurgitation (FMR), which carries important prognostic impact. Randomized clinical trials on transcatheter mitral-valve repair have shown conflicting results, and their representativeness in real-world populations are unclear.

Purpose
This real-world study sought to identify the proportion of patients who would be eligible for mitral valve intervention and describe the current referral patterns at an academic center.

Methods
We conducted a single center cross-sectional study enrolling consecutive patients with HFrEF and FMR under guideline directed medical therapy from January 2010 to December 2018. Moderate FMR was defined as the presence of an effective regurgitant orifice area (EROA) of ≥20mm2 or a regurgitant volume (Regvol) of ≥30mL/beat, according to American Society of Echocardiography guidelines. Demographic, clinical, echocardiographic and treatment data were assessed. Main MITRA-FR and COAPT Trial eligibility criteria (NYHA class, left ventricular ejection fraction (LVEF), left ventricle end-systolic diameter, pulmonary artery systolic pressure, and right ventricle dysfunction) were applied according to trial protocols. Patterns of referral for mitral valve intervention were assessed by pre-procedural transesophageal echocardiography for mitral regurgitation evaluation.

Results
A total of 175 patients with at least moderate FMR were included in the analysis (mean age 70±12 years, 80% male, mean LVEF 32% ±9).
After applying the main eligibility criteria for each study, 73.7% (n=129) of patients would have been enrolled in MITRA-FR trial, whereas only 27.4% (n=48) patients would have met criteria for COAPT trial (Figure 1). Patients with MITRA-FR profile had a mean EROA 25±8 mm2; mean Regvol 36±9 mL/beat; mean LVEDV 205±72 mL; EROA/LVEDV ratio 0.13±0.04. “COAPT-like” patients had a mean EROA 33±10 mm2; mean Regvol 48±13 mL/beat; mean LVEDV 203±65 mL; mean EROA/LVEDV ratio 0.17±0.05.
Only 13.1% (n=23) were referred for transesophageal echocardiography in order to establish the criteria of feasibility for mitral intervention. A total of 16 patients (9.1%) were submitted to mitral valve intervention during follow-up.

Conclusion
In a real-world population of HFrEF patients with significant FMR, more than one fourth of patients had a “COAPT-like” profile and could have benefited from percutaneous mitral valve intervention. The referral rate for evaluation for a potential intervention was low, which precludes patients from benefiting from this type of treatment.

Funding Acknowledgement
Type of funding sources: None.
Regurgitant volume to left ventricular end-diastolic volume ratio: the quest to identify Disproportionate MR is not over
Authors: Albuquerque F , M Lopes P , Freitas P , M Ferreira A , Abecasis J , Trabulo M , Canada M , Ribeiras R , Mendes M , Joao Andrade M 
Published: October 2021

Abstract

Background
Quantification of secondary mitral valve regurgitation (SMR) remains challenging. Proportionate and Disproportionate SMR provides a conceptual framework that relates the degree of SMR to left ventricular dilatation and dysfunction. In line with this concept, regurgitant volume to LV end-diastolic volume ratio (Rvol/LVEDV) was recently proposed as a possible strategy to identify patients with Disproportionate SMR. The aim of this study was to validate this approach in a Portuguese cohort.

Methods
In a single center cohort of patients with heart failure and reduced left ventricular ejection fraction (HFrEF &lt;50%) under optimal guideline-directed medical therapy (GDMT), we retrospectively identified those with at least moderate SMR. According to the published literature, we divided the study population into 2 risk groups: those with a Rvol/LVEDV ratio ≥20% (greater MR/smaller LVEDV) and those with a ratio &lt;20% (smaller MR/ larger EDV). Cox regression and Kaplan-Meier survival analysis were used to assess the association between Rvol/LVEDV ratio and all-cause mortality.

Results
A total of 154 patients (mean age 69±12 years; 81% male) were included. Mean LVEF was 31±8% and median LVEDV was 193 mL (IQR: 155 to 236 mL). There were 74 patients (48.1%) with a Rvol/LVEDV ratio &lt;20% and 80 patients (51.9%) Rvol/LVEDV ratio ≥20%. Regarding GDMT, 141 (91.6%) received beta-blockers, 139 (90.3%) angiotensin converting–enzyme inhibitors/angiotensin receptor blockers and 77 (50.0%) were under mineralocorticoid therapy. Also, there were patients 49 (31.8%) under cardiac resynchronization therapy and 40 patients (26.0%) had an implantable cardioverter defibrillator. During a median follow-up of 2.1 years (IQR 0.7 to 3.8 years), 92 (59.7%) patients died. Cox regression and survival analysis showed no mortality difference between patients with a Rvol/LVEDV ratio &lt;20% and those with a ratio ≥20% (HR: 1.04; 95% CI 0.69–1.57; P=0.854; Log-rank P=0.967) – see also figure.

Conclusion
In a Portuguese cohort of HFrEF patients under optimized GDMT and with at least moderate SMR, the Rvol/LVEDV ratio was not associated with an increased risk of all-cause mortality. As such, the Rvol/LVEDV ratio does not seem to be a reliable surrogate of Disproportionate SMR, possibly because it does not account for the degree of LV dysfunction.

Funding Acknowledgement
Type of funding sources: None.
Impact of gender on long-term prognosis after transcatheter edge-to-edge repair for mitral regurgitation
Authors: Geyer M , Keller K , Born S , Bachmann K , Hell M M , Tamm A R , Ruf T F , Kreidel F , Petrescu A , Schnitzler K , Schmitt V H , Da Rocha E Silva J G , Schulz E , Munzel T , Von Bardeleben R S 
Published: October 2021

Abstract

Background
A symptomatic and prognostic benefit by Transcatheter edge-to-edge repair (TEER) for mitral regurgitation (MR) has been proven. A variety of individual factors including female sex has been suggested to be associated with adverse outcome in cardio-surgical procedures.

Purpose
While gender is factored in common risk factor models for adverse outcome, evidence on sex-specific differences in long-term outcome after TEER for MR is limited. We aimed to investigate the impact of gender on prognosis in a large monocentric cohort with long-term follow-up.

Methods
We analyzed survival stratified for gender after successful isolated edge-to-edge repair of MR in the period between 06/2010 and 03/2018 (exclusion of combined forms of TMVR) in a monocentric retrospective cohort by performing survival analyses and cox regression analyses.

Results
Consecutively, 627 patients (47.0% females, 57.4% functional MR; survival status was available in 96.7%) entered the study and were followed for a median follow-up period of 462 days [IQR 142–945 days]. Survival rates were 97.6% at discharge, 75.7% after 1, 54.5% after 3, 37.6% after 5 and 21.7% after 7 years. Risk score as calculated by the Logistic Euroscore I did not differ significantly between females and males (at baseline: 25.0 [IQR 18.0/34.8] vs. 27.0 [18.4/40.1]%, p=0.093) and no relevant differences were found for in-hospital (2.0 vs. 2.7%, p=0.613), 30 days (4.8 vs. 6.5%, p=0.473) and 1-year mortality (27.0 vs. 25.3%, p=0.675). At the time of procedure, women were older (79.9 [IQR 75.6/84.4] vs. 78.3 [72.9/83.4] years, p&lt;0.001), were less often affected by coronary artery disease (53.1% vs. 75.0% p&lt;0.001), diabetes mellitus (23.7% vs. 31.3%, p=0.040) and impaired left ventricular function (44.5±12.9% vs. 38.9±13.4%, p&lt;0.001). Regarding long-term survival, women had a better prognosis after MR-therapy, especially in functional etiology: e.g., 4-year survival in FMR 65.7 vs. 35.7%, p=0.006 (Figure 1). Remarkably, female sex was associated with a lower risk for long-term mortality in the Cox-regression models, especially in the FMR subgroup (total cohort: univariate HR 0.81 [0.62–1.04], p=0.101; FMR: univariate HR 0.68 [0.49–0.96], p=0.028).

Conclusion
In our cohort of patients undergoing TEER for MR, we found no evidence for an impaired short- and mid-term prognosis for female patients. In contrary and not as indicated by Logistic Euroscore, female sex was associated with better long-term survival in comparison to men despite higher median age, which might be partly explained by a slightly more favorable cardiovascular risk profile.

Funding Acknowledgement
Type of funding sources: None. Figure 1