bluuebunny/crossref_metadata_2025_split huggingface dataset:
Racial disparities in the treatment of aortic stenosis: Has transcatheter aortic valve replacement bridged the gap?
Authors: Erinne Ikenna , Sethi Ankur , Johannesen Justin , Kassotis John 
Published: February 2021

AbstractBackgroundRacial disparities in outcomes and utilization of surgical aortic valve replacement (SAVR) for the treatment of severe aortic stenosis (AS) is well known. While transcatheter aortic valve replacement (TAVR) has become more widespread, its impact on racial disparities remains unclear.ObjectivesOur goal was to assess the utilization of SAVR and TAVR and their clinical outcomes among various racial groups.MethodsThe National Inpatient database (2009–2015) was used to study the racial distribution of admissions for SAVR and TAVR, and their impact on inpatient outcomes. Survey estimation commands were used to determine weighted national estimates.ResultsThere were 3,445,267; 294,108; and 52,913 inpatient visits for AS, SAVR, and TAVR, respectively. SAVR visits were 86% White, 3.8% Black, 5.5% Hispanic, 1.2% Asian/Pacific Islander (A/PI), 0.4% Native American (NA), and 2.9%; TAVR were 87.7% White, 3.7% Black, 3.8% Hispanic, 1.0% A/PI, 0.2% NA, and 3.5% Other while AS visits were 83.7% White, 6.7% Black, 5.3% Hispanic, 1.7% A/PI, 0.4% NA, and 2.2% Other. Racial minorities generally had more co‐morbidities compared with Whites. After SAVR, Black patients had a higher unadjusted inpatient mortality than Whites, however, there was no difference after adjustment for other variables. A/PI were more likely to require a permanent pacemaker after SAVR. Need for blood transfusion was significantly higher among the minorities compared with Whites, except for NA, but there were no racial differences in stroke rates. There was no difference in inpatient mortality, pacemaker implantation, stroke, and bleeding after TAVR, but acute kidney injury occurred more often in Hispanics, A/PI, and “others” compared with Whites.ConclusionsRacial disparities in the treatment of AS continues in the contemporary era; however it was found that TAVR resulted in comparable inpatient outcomes, despite higher comorbidities, and adverse socioeconomic factors in minorities.
Clinical outcomes of patients with and without chronic kidney disease undergoing endovascular revascularization of infrainguinal peripheral artery disease: Insights from the XLPAD registry
Authors: Kabir Ryan , Vuppala Suchith , Liu Yulun , Tejani Ishita , Weideman Rick , Banerjee Avantika , Tsai Shirling , Huffman Lynn , Niazi Khusrow , Brilakis Emmanouil S. , Shishehbor Mehdi H. , Banerjee Subhash 
Published: February 2021

AbstractObjectivesThe purpose of the present study was to define clinical outcomes of chronic kidney disease (CKD) patients undergoing endovascular revascularization of infrainguinal peripheral artery disease (PAD).BackgroundCKD is an established predictor of advanced PAD. However, clinical outcomes for these patients following endovascular revascularization remain inadequately defined.MethodsUsing the ongoing multicenter Excellence in Peripheral Artery Disease (XLPAD) registry (NCT01904851), we analyzed all‐cause death, target limb amputation, and need for repeat revascularization for patients with and without CKD undergoing infrainguinal endovascular revascularization between the years 2005 and 2018.ResultsOf 3,699 patients, 15.1% (n = 559) had baseline CKD. CKD patients had significantly higher incidence of heavily calcified lesions (48.4% vs. 38.1%, p < .001) and diffuse disease (66.9% vs. 61.5%, p = .007). Kaplan–Meier analysis showed significant differences between CKD and non‐CKD patient outcomes at 12 months for freedom from target limb amputation (79.9% vs. 92.7%, p < .001) and all‐cause death (90.1% vs. 97.6%, p < .001). However, freedom from target vessel revascularization was similar between the groups. After adjusting for baseline comorbidities in the CKD and non‐CKD groups, the hazard ratios for target limb amputation and death at 12 months were 2.28 (95% confidence interval or CI 1.25–4.17, p < .001) and 4.38 (95% CI 2.58–7.45, p < .001), respectively.ConclusionsFollowing endovascular revascularization for infrainguinal PAD, CKD was an independent predictor of all‐cause death and target limb amputation at 12 months.
Virtual support for remote proctoring in TAVR during COVID‐19
Authors: Arslan Fatih , Gerckens Ulrich 
Published: February 2021

AbstractObjectivesThe current report describes a single operator's experience of the first use of smartglass technology as a facilitator of virtual support during TAVR proctoring.BackgroundRestricted gatherings and containment measures during the ongoing COVID‐19 pandemic have a major impact on daily clinical practice. Interaction between peers is crucial in science, clinical practice, and education. In addition, there is also a growing importance of proctoring in interventional cardiology for structural heart disease. Virtual support may facilitate the wide implementation of remote proctoring.MethodsA collaboration between a smartglass provider (Rods & Cones) and self‐expandable transcatheter aortic heart valve system (Medtronic) was initiated and tested extensively prior to TAVR procedures. Two cases were randomly selected for remote support. The light‐weight smartglass consisted of a full HD central camera, a 720p ×5 optical zoom camera, built‐in LED light, speaker and earphone jack, and an external visor to project data in a nonobstructive manner in the operators' view.ResultsPreprocedural detailed discussion of the cases between the proctor and the operator occurred via teleconferencing. Successful procedural virtual support was determined by the presence of a session coordinator, high quality of the central camera, high‐speed and stable wireless internet connection. Limitations were the relative discomfort of the earpieces, discordance between the central and zoom camera and the absence of visual fixation during head motions.ConclusionIn a highly complex and demanding context such as TAVR, remote proctoring by means of virtual support is feasible and efficacious.
Nickel‐Catalyzed Acyl Group Transfer of o‐Alkynylphenol Esters Accompanied by C−O Bond Fission for Synthesis of Benzo[b]furan
Authors: Doi Ryohei , Shimizu Koji , Ikemoto Yuma , Uchiyama Masashi , Koshiba Mikiko , Furukawa Atsushi , Maenaka Katsumi , Watanabe Satoshi , Sato Yoshihiro 
Published: February 2021

AbstractHerein, we report the nickel‐catalyzed cascade C−O bond cleavage/cyclization of ortho‐alkynylphenyl ester to construct a 3‐acylbenzo[b]furan skeleton. As a result of reaction condition screening, the Ni(0)/IAd (1,3‐Di(1‐adamantyl)imidazole‐2‐ylidene) system was found to be optimal for catalytic conversion. Interestingly, the reaction exclusively gives 3‐acylbenzo[b]furan instead of a decarbonylated product frequently observed in reactions mediated by acyl‐nickel species. The catalyst loadings could be reduced to 5–10 mol %. We demonstrated the synthesis of a variety of functionalized 3‐acylbenzofuran derivatives. We conducted stoichiometric study of nickel complexes as well as density functional theory (DFT) calculations to support a possible reaction mechanism.
A high voltage pulse generator using avalanche‐mode thyristors
Authors: Naito Takashi , Akemoto Mitsuo 
Published: February 2021

AbstractA high voltage and high current pulse switch using avalanche mode thyristor has been developed for the high voltage pulse generator. When the break‐over voltage is applied to a thyristor, the thyristor turns on without the gate input current. We call avalanche mode thyristor (AMT) which operates such a switch mode. AMT has many advantages, for example, turn on function without trigger input circuit in the series connection, high speed switching characteristics, etc. A magnetic switch (MS) using the saturation of the core is adopted for the high current pulse shaping. Twelve stages of AMTs generate 11 kV and 1.36 kA with 260 nanoseconds pulse width. A high voltage pulse has been produced up to 65 kV, 43A by using the AMT pulse generator and a pulse trans. The behavior of AMT and the performance of the circuit are discussed.
INTERVENE‐HF: feasibility study of individualized, risk stratification‐based, medication intervention in patients with heart failure with reduced ejection fraction
Authors: Zile Michael R. , Costanzo Maria Rosa R. , Ippolito Ekaterina M. , Zhang Yan , Stapleton Russell , Sadhu Ashish , Jimenez Javier , Hobbs Joe , Sharma Vinod , Warman Eduardo N. , Streeter Lindsay , Butler Javed 
Published: February 2021

AbstractAimsDetermine the feasibility of implementing a heart failure (HF) management strategy that (i) uses a device‐based, remote, dynamic, multimetric risk stratification model to predict the risk of HF events and (ii) uses a standardized, centrally administered, ambulatory medication intervention protocol to reproducibly and safely decrease elevated risk scores.Methods and resultsProspective, non‐randomized, single‐arm, multicenter feasibility study (Intervene‐HF) was conducted in HF patients implanted with a cardiac resynchronization therapy with implantable cardio defibrillator (CRT‐D) with TriageHF risk score feature. Certified HF nurses (CHFN) in the Medtronic Care Management Services Program implemented an ambulatory medication intervention strategy by following a standardized guided action pathway triggered by risk‐based alert. When CHFN received notification of increased risk score (HF care alert), they implemented a 3 day course of diuretic up‐titration (PRN) previously prescribed by a physician. Safety was monitored daily. Recovery after PRN was defined as ≥70% recovery of impedance toward baseline levels. Sixty‐six patients followed for 8.2 ± 3.9 months had 49 HF care alerts. Twenty‐three of 49 alerts did not receive PRN due to protocol‐mandated criteria. Twenty‐six of 49 alerts received PRN, 22 were completed, and 19 led to impedance recovery. Four interventions were stopped for safety without leading to an adverse event (AE). One of 26 PRNs was followed by a HF event. Eighty‐five per cent (22/26) of PRNs were completed without an AE; 69% (18/26) met the recovery criteria.ConclusionsThe Intervene‐HF study supports the feasibility of testing, in a large randomized clinical trial, an ambulatory medication intervention strategy that is physician‐directed, CHFN‐implemented, and based on individualized device risk stratification.
Numerical study of the vortex‐induced electroosmotic mixing of non‐Newtonian biofluids in a nonuniformly charged wavy microchannel: Effect of finite ion size
Authors: Mehta Sumit Kumar , Pati Sukumar , Mondal Pranab Kumar 
Published: February 2021

AbstractWe propose a micromixer for obtaining better efficiency of vortex induced electroosmotic mixing of non‐Newtonian bio‐fluids at a relatively higher flow rate, which finds relevance in many biomedical and biological applications. To represent the rheology of non‐Newtonian fluid, we consider the Carreau model in this study, while the applied electric field drives the constituent components in the micromixer. We show that the spatial variation of the applied field, triggered by the topological change of the bounding surfaces, upon interacting with the non‐uniform surface potential gives rise to efficient mixing as realized by the formation of vortices in the proposed micromixer. Also, we show that the phase‐lag between surface potential leads to the formation of asymmetric vortices. This behavior offers better mixing performance following the appearance of undulation on the flow pattern. Finally, we establish that the assumption of a point charge in the paradigm of electroosmotic mixing, which is not realistic as well, under‐predicts the mixing efficiency at higher amplitude of the non‐uniform zeta potential. The inferences of the present analysis may guide as a design tool for micromixer where rheological properties of the fluid and flow actuation parameters can be simultaneously tuned to obtain phenomenal enhancement in mixing efficiency.
Towards understanding organic matter fluxes and reactivity in surface waters: Filtering impact on DOC and POC degradation
Authors: Moody Catherine Sarah , Worrall Fred 
Published: February 2021

AbstractPeatlands cover a very small area of the Earth, but store globally significant quantities of carbon and export disproportionate quantities of fluvial organic carbon, especially when the peatlands are degraded or disturbed. Peatland headwater catchments with high concentrations of dissolved and particulate organic carbon (DOC and POC) provide an opportunity to investigate the possibility of competing effects that could lead to enhanced or diminished turnover of DOC in the presence of POC. Both POC and DOC can be degraded by light and microbes, producing smaller molecules and releasing CO2 and CH4 to the atmosphere, and POC can inhibit light penetration, stabilize DOC by providing adsorption sites and providing surfaces for microbes to interact with DOC. However, the majority of peatland fluvial carbon studies are conducted using filtered water samples, and measure only the DOC concentration, so the impact of the particulate organic matter (POM) on in‐stream processing of organic carbon is relatively unknown. It is therefore possible that studies have underestimated carbon transformations in rivers as they have not considered the interaction of the particulate material on the dissolved concentrations; there could be higher losses than previously estimated, increasing the contribution of peatland headwaters to GHG emissions. In this study, we assessed if the current approach of DOC degradation studies accurately represent the impact of POM on DOC degradation, by quantifying DOC production from POM, and therefore POC, over time in water with manipulated POM concentrations. Both filtered and unfiltered water lost 60% of the DOC over 70 hours, whereas the treatment with additional POM lost only 35%. The results showed that filtering does not significantly impact the DOC degradation rates; however, when the POC concentration was doubled, there was a significant reduction in DOC degradation, suggesting that filtering would still be necessary to get accurate rates of DOC transformations in waters with high POC concentrations.
Investigating the fluctuations of exchange rate based on monetary‐behaviour approach
Authors: Tajdini Saeid , Mehrara Mohsen , Taiebnia Ali 
Published: February 2021

AbstractThe purpose of this study is to investigate the excessive changes in the exchange rate in Iran during 2018 due to extreme speculation in the monetary and currency markets caused by numerous economic and political factors such as accumulated excessive liquidity, severe sanctions and foreign pressures. Based on purchasing power parity (PPP) theory, the foreign exchange rate has to be adjusted with the inflation rate. However, this study showed that in the critical situations the PPP theory, which adopts a long‐term and backward‐looking approach, no longer works, and instead the market tends to adopt a short‐term and prospective approach to exchange rates. In this study, the economic data of Iran and the United States were gathered from late 1978 to 21 September 2018, and by adding three other economic factors, including the difference of average annual growth rate of GDP per capita of 2% between the two countries, indicator of risk in low volatility period (1.16%) and high volatility one (1.49%), a new and risk‐based approach is presented based on the low and high volatility of the exchange rates to address the excessive changes not explained by conventional theories.
The impact of COVID‐19 pandemic on hospitality stock returns in China
Authors: Lee Chi‐Chuan , Lee Chien‐Chiang , Wu Yizhong 
Published: February 2021

AbstractCoronavirus disease (COVID‐19) has already devastated the world, and the economy becomes the most critical challenge for any country worldwide. The increasing uncertainty of the COVID‐19 outbreak has made stock markets in China more turbulent and less predictable. Under the current exceptional circumstances, the hospitality industry suffered the most due to the travel restrictions. This research thus assesses the dynamic relationship among the COVID‐19 outbreak, macroeconomic fluctuations and hospitality stock returns based on a structural VAR framework from 13 January to 11 May 2020, in China. Evidence reveals that macroeconomic fluctuations and hospitality stock returns are significantly affected by shocks from the COVID‐19 outbreak. An unanticipated positive change of the COVID‐19 explosion triggers an addition in exchange rates and causes a reduction in the stock market and hospitality industry returns. For the impacts of the exchange rate, findings reveal that a surprise increase in exchange rates (currency depreciation) exerts a significant negative influence on stock market returns. Additionally, a positive change of stock market returns is linked to a decline in exchange rates and a rise in hospitality industry returns. Therefore, knowledge of these relationships can enable policymakers to evaluate and implement effective policies to stabilize the stock markets and help investors to make appropriate investment strategies.
Spectrophotometric evaluation of hemolysis in plasma by quantification of free oxyhemoglobin, methemoglobin, and methemalbumin in presence of bilirubin
Authors: Heckl Christian , Lang Alexander , Rühm Adrian , Sroka Ronald , Duffield Thomas , Vogeser Michael , Paal Michael 
Published: February 2021

AbstractSevere intravascular hemolysis leads to the simultaneous presence of free heme pigments (oxyhemoglobin, methemoglobin, and methemalbumin) and bilirubin in human plasma. Standard spectrophotometric methods used to assess in vivo hemolysis inadequately address this complex analytical situation. Thus, we propose a novel quantification algorithm to ensure the highest analytical specificity. A corresponding second‐derivative fitting algorithm was validated according to the guideline of bioanalytical method validation from the European Medicines Agency using plasma specimens (n = 1759) spiked with different concentrations of oxyhemoglobin and methemoglobin. The results were compared to standard spectrophotometric quantification methods described by Harboe, Noe, and Fairbanks. Based on the second‐derivative method, simultaneous quantification of oxyhemoglobin and methemoglobin/methemalbumin in samples with total bilirubin concentrations ≤4.9 mg/dL (83.8 μmol/L) provided robust results (inaccuracy ≤20%, imprecision ≤16%). Analyzing UV/VIS spectra of plasma from patients with confirmed severe intravascular hemolysis evidenced an underestimation of up to 33% for the combined free heme pigment content. The employed second‐derivative algorithm allows for automated and highly specific quantification of the free heme pigment content in diluted human plasma, which cannot be realized with standard spectrophotometric evaluation methods. An Excel‐based tool readily applicable to clinical datasets accompanies this manuscript.
Forensic and reliability analyses of fixed dental prostheses
Authors: Mecholsky John J. , Hsu Shu‐Min , Jadaan Osama , Griggs Jason , Neal Daniel , Clark Arthur E. , Xia Xinyi , Esquivel‐Upshaw Josephine F. 
Published: February 2021

AbstractThis article describes the protocol for determining the cause of failure for retrieved failed implant supported fixed dental prostheses (FDPs) in a clinical study of three‐unit bridges. The results of loading of flexure bars of different veneer compositions at different stress rates were presented for two veneer materials (leucite reinforced and fluorapatite glass–ceramic veneers) and a Y‐TZP core zirconia ceramic used in the clinical study. From these results, the strengths of the fast loading conditions were used to determine the fracture toughness of these materials. Fractal dimension measurements of the flexure bars and selected FDPs of the same materials demonstrated that the values were the same for both the bars and the FDPs. This allowed the use of fracture toughness values from the flexure bars to determine the strengths of the FDPs. The failure analysis of clinically obtained FDP replicates to determine the size of the fracture initiating cracks was then performed. Using the information from the flexure bars and the size of the fracture initiating cracks for the failed FDPs, the strengths of the FDPs were determined. The clinical failures were determined to be most likely the result of repeated crack growth due to initial overload and continuous use after initial cracking.
Cellulose from oil palm empty fruit bunch fiber and its conversion to carboxymethylcellulose
Authors: Yimlamai Benyathip , Choorit Wanna , Chisti Yusuf , Prasertsan Poonsuk 
Published: February 2021

AbstractBACKGROUNDHigher‐value products, such as cellulose and carboxymethylcellulose (CMC), may be produced from lignocellulosic agroindustrial residues, such as oil palm empty fruit bunch (EFB) fibers that are presently underutilized or discarded. Recovery of cellulose from EFB and its conversion of CMC are discussed as methods of creating value and reducing the environmental impact of EFB.RESULTSCellulose was recovered from EFB fibers and converted to water soluble CMC. Cellulose isolation used a two‐step sequential treatment involving peracetic acid (PA) (50 g dry EFB L−1 PA, 35 °C, 9 h) for initial delignification, and then alkaline peroxide (AP) (50 g delignified‐EFB L−1 AP, 45 °C, 12 h). This treatment removed 91.5% of lignin in the original EFB fiber. The recovered solids, designated as cellulose‐EFB, were comprised of 83.7 ± 3.4% cellulose, 5.6 ± 0.3% hemicellulose, 1.7 ± 0.0% lignin, and 1.7 ± 0.1% ash. A two‐step process with an initial alkalization {3 g cellulose‐EFB in 99 mL solvent [10:1 by vol mixture of ethanol (95%) and 35% NaOH], 30 °C, 2 h} followed by etherification was used to convert cellulose‐EFB to CMC sodium salt. The conversion yield was 50% of the theoretical maximum.CONCLUSIONThe best conditions for preparing CMC from cellulose‐EFB were a 2 h treatment with 35% (wt/vol) NaOH during alkalization at 30 °C, followed by etherification at 55 °C. The CMC had a degree of substitution of 0.16 and a water solubility of 6.8 g L−1 at 30 °C. © 2021 Society of Chemical Industry
Brain tumor segmentation using K‐means clustering and deep learning with synthetic data augmentation for classification
Authors: Khan Amjad Rehman , Khan Siraj , Harouni Majid , Abbasi Rashid , Iqbal Sajid , Mehmood Zahid 
Published: February 2021

AbstractImage processing plays a major role in neurologists' clinical diagnosis in the medical field. Several types of imagery are used for diagnostics, tumor segmentation, and classification. Magnetic resonance imaging (MRI) is favored among all modalities due to its noninvasive nature and better representation of internal tumor information. Indeed, early diagnosis may increase the chances of being lifesaving. However, the manual dissection and classification of brain tumors based on MRI is vulnerable to error, time‐consuming, and formidable task. Consequently, this article presents a deep learning approach to classify brain tumors using an MRI data analysis to assist practitioners. The recommended method comprises three main phases: preprocessing, brain tumor segmentation using k‐means clustering, and finally, classify tumors into their respective categories (benign/malignant) using MRI data through a finetuned VGG19 (i.e., 19 layered Visual Geometric Group) model. Moreover, for better classification accuracy, the synthetic data augmentation concept i s introduced to increase available data size for classifier training. The proposed approach was evaluated on BraTS 2015 benchmarks data sets through rigorous experiments. The results endorse the effectiveness of the proposed strategy and it achieved better accuracy compared to the previously reported state of the art techniques.