bluuebunny/crossref_metadata_2025_split huggingface dataset:
Robust control under worst‐case uncertainty for unknown nonlinear systems using modified reinforcement learning
Authors: Perrusquía Adolfo , Yu Wen 
Published: February 2020

SummaryReinforcement learning (RL) is an effective method for the design of robust controllers of unknown nonlinear systems. Normal RLs for robust control, such as actor‐critic (AC) algorithms, depend on the estimation accuracy. Uncertainty in the worst case requires a large state‐action space, this causes overestimation and computational problems. In this article, the RL method is modified with the k‐nearest neighbor and the double Q‐learning algorithm. The modified RL does not need the neural estimator as AC and can stabilize the unknown nonlinear system under the worst‐case uncertainty. The convergence property of the proposed RL method is analyzed. The simulations and the experimental results show that our modified RLs are much more robust compared with the classic controllers, such as the proportional‐integral‐derivative, the sliding mode, and the optimal linear quadratic regulator controllers.
Cover Image
Authors: Lu Zhenyu , Huang Panfeng , Liu Zhengxiong 
Published: February 2020

SummaryThe cover image is based on the Research Article High‐gain nonlinear observer‐based impedance control for deformable object cooperative teleoperation with nonlinear contact model by Zhenyu Lu et al., https://doi.org/10.1002/rnc.4880.
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Advancements in the stability design of steel frames considering general non‐prismatic members
Authors: White Donald W. , Slein Ryan , Toğay Oğuzhan 
Published: February 2020

AbstractThis paper discusses an innovative approach to the design of planar steel frames composed of prismatic and/or non‐prismatic members. The method evaluates the member stability limit states using an inelastic eigenvalue buckling analysis configured with column, beam and beam‐column inelastic stiffness reduction factors derived from the ANSI/AISC 360‐16 Specification. The resulting procedure provides a relatively rigorous evaluation of all member strength limits accounting for moment and axial force variations along the member lengths, non‐prismatic geometry effects, general out‐of‐plane bracing conditions and beneficial end restraint from less‐critical adjacent, unbraced segments and/or from end conditions. The approach uses a geometric non‐linear pre‐buckling analysis based on the AISC direct analysis method to estimate the in‐plane internal forces. Given these forces, an eigenvalue buckling solution is conducted to evaluate the overall member stability. Other limit states are addressed through cross‐section strength checks using the internal forces determined from the geometric non‐linear load‐displacement analysis. Calculations using this approach are compared with results from recent experimental tests.
A verified and optimized Stream X‐Machine testing method, with application to cloud service certification
Authors: Simons Anthony J. H. , Lefticaru Raluca 
Published: February 2020

SummaryThe Stream X‐Machine (SXM) testing method provides strong and repeatable guarantees of functional correctness, up to a specification. These qualities make the method attractive for software certification, especially in the domain of brokered cloud services, where arbitrage seeks to substitute functionally equivalent services from alternative providers. However, practical obstacles include the difficulty in providing a correct specification, the translation of abstract paths into feasible concrete tests and the large size of generated test suites. We describe a novel SXM verification and testing method, which automatically checks specifications for completeness and determinism, prior to generating complete test suites with full grounding information. Three optimization steps achieve up to a 10‐fold reduction in the size of the test suite, removing infeasible and redundant tests. The method is backed by a set of tools to validate and verify the SXM specification, generate technology‐agnostic test suites and ground these in SOAP, REST or rich‐client service implementations. The method was initially validated using seven specifications, three cloud platforms and five grounding strategies.
Survival outcome in severe left‐sided congenital diaphragmatic hernia with and without fetal endoscopic tracheal occlusion in a country with suboptimal neonatal management
Authors: Cruz‐Martínez R. , Martínez‐Rodríguez M. , Gámez‐Varela A. , Nieto‐Castro B. , Luna‐García J. , Juárez‐Martínez I. , López‐Briones H. , Guadarrama‐Mora R. , Torres‐Torres J. , Coronel‐Cruz F. , Ibarra‐Rios D. , Ordorica‐Flores R. , Nieto‐Zermeño J. 
Published: February 2020

ABSTRACTObjectiveTo evaluate the impact of fetal endoscopic tracheal occlusion (FETO) on improving survival of fetuses with severe left‐sided congenital diaphragmatic hernia (CDH), as compared with contemporaneous cases managed expectantly during pregnancy, in a country with suboptimal neonatal management.MethodsIn this prospective cohort study, consecutive fetuses with isolated left‐sided CDH, normal karyotype and severe pulmonary hypoplasia (defined as liver herniation and observed/expected lung‐to‐head circumference ratio below 26%) were selected for FETO at less than 32 weeks of gestation in a single tertiary referral center in Queretaro, Mexico. Postnatal outcome (survival up to 28 days after birth) was compared between fetuses treated with FETO and contemporaneous cases with similar lung size managed expectantly during pregnancy.ResultsTwenty‐five fetuses with isolated severe left‐sided CDH treated with FETO were matched individually with 25 cases managed expectantly during pregnancy. Endotracheal placement of the balloon was performed successfully on the first attempt in all cases. The median gestational age (GA) at balloon placement was 29.1 (range, 25.6–31.8) weeks and 34.1 (range, 30.0–36.1) weeks at balloon removal. There were no technical problems with the introduction or removal of the balloon in any cases. The median GA at delivery was significantly lower in the group treated with FETO than in those managed expectantly (35.3 vs 37.7 weeks; P = 0.04). The survival rate was significantly higher in the group treated with FETO than in those without fetal intervention (32% vs 0%; P < 0.001).ConclusionIn settings with suboptimal neonatal management, FETO was associated with improved neonatal survival in fetuses with isolated left‐sided CDH and severe pulmonary hypoplasia. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.
A new dynamic inflow model for vertical‐axis wind turbines
Authors: De Tavernier Delphine , Ferreira Carlos S. 
Published: February 2020

AbstractThis paper presents a new dynamic inflow model for vertical‐axis wind turbines (VAWTs). The model uses the principle of Duhamel's integral. The indicial function of the inflow‐ and crossflow‐induction required to apply Duhamel's integral is represented by an exponential function depending on the thrust coefficient and the azimuthal position. The parameters of this approximation are calibrated using a free wake vortex model. The model is compared with the results of a vortex model and higher fidelity computational fluid dynamic (CFD) simulations for the response of an actuator cylinder to a step input of the thrust and to a cyclic thrust. It is found that the discrepancies of the dynamic inflow model increase with increasing reduced frequency and baseline thrust. However, the deviations remain small. Analysing the application of a finite‐bladed floating VAWT with non‐uniform loading and validating it against actuator line CFD results that intrinsically include dynamic inflow shows that the new dynamic inflow model significantly outperforms the Larsen and Madsen model (which is the current standard in fully coupled VAWT models) and enhances the modelling of VAWTs.
A review of mammographic region of interest classification
Authors: Yengec Tasdemir Sena B. , Tasdemir Kasim , Aydin Zafer 
Published: February 2020

AbstractEarly detection of breast cancer is important and highly valuable in clinical practice. X‐ray mammography is broadly used for prescreening the breast and is also attractive due to its noninvasive nature. However, experts can misdiagnose a significant proportion of the cases, which may either cause redundant examinations or cancer. In order to reduce false positive and negative rates of mammography screening, computer‐aided breast cancer detection has been studied for more than 30 years and many methods have been proposed by the researchers. In this review, region of interest (ROI) classification methods, which operate on a predefined or segmented ROIs with a focus on mass classification are surveyed. A total of 72 high quality journal and conference papers are selected from the Web of Science (WOS) database that meet several inclusion criteria. A comparative analysis is provided based on ROI extraction methods, data sets and machine learning techniques employed, the prediction accuracies, and usage frequency statistics. Based on the performances obtained on publicly available data sets, the ROI classification problem from mammogram images can be considered as approaching to be solved. Nonetheless, it can still be used as complementary information in breast cancer detection from the whole mammograms, which has room for improvement.This article is categorized under:
Application Areas > Science and Technology
Technologies > Machine Learning
Technologies > Classification
Bootstrapping inflationary correlators in Mellin space
Authors: Sleight Charlotte , Taronna Massimo 
Published: February 2020

Abstract
We develop a Mellin space approach to boundary correlation functions in anti-de Sitter (AdS) and de Sitter (dS) spaces. Using the Mellin-Barnes representation of correlators in Fourier space, we show that the analytic continuation between AdSd+1 and dSd+1 is encoded in a collection of simple relative phases. This allows us to determine the late-time tree-level three-point correlators of spinning fields in dSd+1 from known results for Witten diagrams in AdSd+1 by multiplication with a simple trigonometric factor. At four point level, we show that Conformal symmetry fixes exchange four-point functions both in AdSd+1 and dSd+1 in terms of the dual Conformal Partial Wave (which in Fourier space is a product of boundary three-point correlators) up to a factor which is determined by the boundary conditions. In this work we focus on late-time four-point correlators with external scalars and an exchanged field of integer spin-ℓ. The Mellin-Barnes representation makes manifest the analytic structure of boundary correlation functions, providing an analytic expression for the exchange four-point function which is valid for general d and generic scaling dimensions, in particular massive, light and (partially-)massless fields. It moreover naturally identifies boundary correlation functions for generic fields with multi-variable Meijer-G functions. When d = 3 we reproduce existing explicit results available in the literature for external conformally coupled and massless scalars. From these results, assuming the weak breaking of the de Sitter isometries, we extract the corresponding correction to the inflationary three-point function of general external scalars induced by a general spin- ℓ field at leading order in slow roll. These results provide a step towards a more systematic understanding of de Sitter observables at tree level and beyond using Mellin space methods.
Generation of vortices and stabilization of vortex lattices in holographic superfluids
Authors: Li Xin , Tian Yu , Zhang Hongbao 
Published: February 2020

Abstract
Within the simplest holographic superfluid model and without any ingredient put by hand, it is shown that vortices can be generated when the angular velocity of rotating superfluids exceeds certain critical values, which can be precisely determined by linear perturbation analyses (quasi-normal modes of the bulk AdS black brane). These vortices appear at the edge of the superfluid system first, and then automatically move into the bulk of the system, where they are eventually stabilized into certain vortex lattices. For the case of 18 vortices generated, we find (at least) five different patterns of the final lattices formed due to different initial perturbations, which can be compared to the known result for such lattices in weakly coupled Bose-Einstein condensates from free energy analyses.
Comprehensive chemical characterization of the aerosol generated by a heated tobacco product by untargeted screening
Authors: Bentley Mark C. , Almstetter Martin , Arndt Daniel , Knorr Arno , Martin Elyette , Pospisil Pavel , Maeder Serge 
Published: February 2020

AbstractA suite of untargeted methods has been applied for the characterization of aerosol from the Tobacco Heating System 2.2 (THS2.2), a heated tobacco product developed by Philip Morris Products S.A. and commercialized under the brand name IQOS®. A total of 529 chemical constituents, excluding water, glycerin, and nicotine, were present in the mainstream aerosol of THS2.2, generated by following the Health Canada intense smoking regimen, at concentrations ≥ 100 ng/item. The majority were present in the particulate phase (n = 402), representing more than 80% of the total mass determined by untargeted screening; a proportion were present in both particulate and gas-vapor phases (39 compounds). The identities for 80% of all chemical constituents (representing > 96% of the total determined mass) were confirmed by the use of authentic analytical reference materials. Despite the uncertainties that are recognized to be associated with aerosol-based untargeted approaches, the reported data remain indicative that the uncharacterized fraction of TPM generated by THS2.2 has been evaluated to the fullest practicable extent. To the best of our knowledge, this work represents the most comprehensive chemical characterization of a heated tobacco aerosol to date.
Buccal mucosal graft urethroplasty for radiation-induced urethral strictures: an evaluation using the extended Urethral Stricture Surgery Patient-Reported Outcome Measure (USS PROM)
Authors:   for the Trauma and Reconstructive Urology Working Party of the European Association of Urology Young Academic Urologists, Vetterlein Malte W. , Kluth Luis A. , Zumstein Valentin , Meyer Christian P. , Ludwig Tim A. , Soave Armin , Riechardt Silke , Engel Oliver , Dahlem Roland , Fisch Margit , Rosenbaum Clemens M. 
Published: February 2020

Abstract
Objectives
To evaluate objective treatment success and subjective patient-reported outcomes in patients with radiation-induced urethral strictures undergoing single-stage urethroplasty.

Patients and methods
Monocentric study of patients who underwent single-stage ventral onlay buccal mucosal graft urethroplasty for a radiation-induced stricture between January 2009 and December 2016. Patients were characterized by descriptive analyses. Kaplan–Meier estimates were employed to plot recurrence-free survival. Recurrence was defined as any subsequent urethral instrumentation (dilation, urethrotomy, urethroplasty). Patient-reported functional outcomes were evaluated using the validated German extension of the Urethral Stricture Surgery Patient-Reported Outcome Measure (USS PROM).

Results
Overall, 47 patients were available for final analyses. Median age was 70 (IQR 65–74). Except for two, all patients had undergone pelvic radiation therapy for prostate cancer. Predominant modality was external beam radiation therapy in 70% of patients. Stricture recurrence rate was 33% at a median follow-up of 44 months (IQR 28–68). In 37 patients with available USS PROM data, mean six-item LUTS score was 7.2 (SD 4.3). Mean ICIQ sum score was 9.8 (SD 5.4). Overall, 53% of patients reported daily leaking and of all, 26% patients underwent subsequent artificial urinary sphincter implantation. Mean IIEF-EF score was 4.4 (SD 7.1), indicating severe erectile dysfunction. In 38 patients with data regarding the generic health status and treatment satisfaction, mean EQ-5D index score and EQ VAS score was 0.91 (SD 0.15) and 65 (SD 21), respectively. Overall, 71% of patients were satisfied with the outcome.

Conclusion
The success rate and functional outcome after BMGU for radiation-induced strictures were reasonable. However, compared to existing long-term data on non-irradiated patients, the outcome is impaired and patients should be counseled accordingly.
Preoperative prediction of postoperative cerebellar mutism syndrome. Validation of existing MRI models and proposal of the new Rotterdam pCMS prediction model
Authors: BAE Dhaenens , MLC Van Veelen , Catsman-Berrevoets CE 
Published: February 2020

Abstract
Purpose
Postoperative cerebellar mutism syndrome (pCMS) is a complication that may occur after pediatric fossa posterior tumor surgery. Liu et al. developed an MRI-based prediction model to estimate pCMS risk preoperatively. The goal of this study was to validate the model of Liu et al. and if validation was not as sensitive in our group as previously described to develop an easy to use, reliable, and sensitive preoperative risk prediction model for pCMS.

Methods
In this study, 121children with a fossa posterior tumor who underwent surgery at ErasmusMC/Sophia Children’s Hospital, the Netherlands between 2004 and 2018 could be included. Twenty-six percent of them developed pCMS. Preoperative MRI were scored using the Liu et al. model.

Results
The Liu et al. model reached an accuracy of 78%, a sensitivity of 58%, and a specificity of 84% in our cohort. In a new risk model some of the variables of Liu et al. were included as well as some of the recently described preoperative MRI characteristics in pCMS patients by Zhang et al. The new model reached an accuracy of 87%, a sensitivity of 97%, and a specificity of 84% in our patient group.

Conclusion
Because the Liu et al. model did not provide an as accurate risk prediction in our cohort as was expected, we created a new risk prediction model that reached high model accuracy in our cohort that could assist neurosurgeons in determining their surgical tactics and help prepare high risk patients and their parents for this severe complication.
The possibility of endoscopic treatment of cN0 submucosal esophageal cancer: results from a surgical cohort
Authors: Ye Bo , Zhang Xiaobin , Su Yuchen , Hao Shuguang , Teng Haohua , Guo Xufeng , Yang Yu , Sun Yifeng , Mao Teng , Li Zhigang 
Published: February 2020

Abstract
Background
We analyzed the pathological characteristics and recurrence pattern of cN0 submucosal esophageal cancer after esophagectomy and conducted risk stratification to determine the feasibility of performing endoscopic resection for cN0pT1b esophageal squamous cell malignancies.

Methods
We retrospectively enrolled 167 patients who underwent right-sided transthoracic esophagectomy and extended thoracic/abdominal two-field lymphadenectomy. Patients with pathologically confirmed lymph node metastasis or tumor recurrence constituted the high-risk group for endoscopic submucosal resection, and the remainder were defined as low risk. Factors affecting lymphatic metastasis and long-term recurrence were identified by univariate and multivariate analyses.

Results
Postoperative pathology showed that five patients (5/167; 3%) had lymph node metastases. Follow-up ranged from 12–60 months, with a median of 29 months. A total of 17 patients (10.2%) had recurrences during follow-up, including three patients with pathologic nodal metastasis (pN +) found at surgery. Invasion depth, differentiation, and tumor size differed significantly in high-risk patients. Overall 3-year survival rates were 94.2% (low-risk) and 40.9% (high-risk) (p < 0.01). Twenty-one patients with sm1 cancer, high tumor differentiation, and tumor length < 2 cm had no lymph node metastasis or lymphovascular invasion, and none of these patients experienced recurrence.

Conclusions
Endoscopic submucosal resection alone may be feasible for patients with small (≤ 2 cm) clinically N0 submucosal esophageal squamous cell carcinoma with low invasion depth (sm1) and higher differentiation, but prospective studies are required for confirmation. Other patients require surgical resection with extended two-field thoracic/abdominal lymphadenectomy.
Laparoscopic common bile duct exploration in patients with previous abdominal biliary tract operations
Authors: Li Min , Tao Ying , Shen Sheng , Song Lujun , Suo Tao , Liu Han , Wang Yueqi , Zhang Dexiang , Ni Xiaoling , Liu Houbao 
Published: February 2020

Abstract
Background
A history of abdominal biliary tract surgery has been identified as a relative contraindication for laparoscopic common bile duct exploration (LCBDE), and there are very few reports about laparoscopic procedures in patients with a history of abdominal biliary tract surgery.

Methods
We retrospectively reviewed the clinical outcomes of 227 consecutive patients with previous abdominal biliary tract operations at our institution between December 2013 and June 2019. A total of 110 consecutive patients underwent LCBDE, and 117 consecutive patients underwent open common bile duct exploration (OCBDE). Patient demographics and perioperative variables were compared between the two groups.

Results
The LCBDE group performed significantly better than the OCBDE group with respect to estimated blood loss [30 (5–700) vs. 50 (10–1800) ml; p = 0.041], remnant common bile duct (CBD) stones (17 vs. 28%; p = 0.050), postoperative hospital stay [7 (3–78) vs. 8.5 (4.5–74) days; p = 0.041], and time to oral intake [2.5 (1–7) vs. 3 (2–24) days; p = 0.015]. There were no significant differences in the operation time [170 (60–480) vs. 180 (41–330) minutes; p = 0.067]. A total of 19 patients (17%) in the LCBDE group were converted to open surgery. According to Clavien’s classification of complications, the LCBDE group had significantly fewer postoperative complications than the OCBDE group (40 vs. 57; p = 0.045). There was no mortality in either group. Multiple previous operations (≥ 2 times), a history of open surgery, and previous biliary tract surgery (including bile duct or gallbladder + bile duct other than cholecystectomy alone) were risk factors for postoperative adhesion (p = 0.000, p = 0.000, and p = 0.000, respectively).

Conclusion
LCBDE is ultimately the least invasive, safest, and the most effective treatment option for patients with previous abdominal biliary tract operations and is especially suitable for those with a history of cholecystectomy, few previous operations (< 2 times), or a history of laparoscopic surgery.
Heart failure disease management programs in Austria 2019
Authors:   Heart Failure Working Group and the Working Group for Cardiological Assistance and Care Personnel of the Austrian Society for Cardiology, Poelzl Gerhard , Fetz Bettina , Altenberger Johann , Fritsch Margret , Auer Johann , Stachl Elfriede , Boehmer Armin , Frauendorfer Heinrich , Ebner Christian , Geyrhofer Friedrich , Pötz Stefan , Prim Annette , Alber Hannes , de Grandis Renate , Drack Christiane , Hülsmann Martin 
Published: February 2020

SummaryHeart failure (HF) is common and is associated with high morbidity, mortality and high health expenditure. A multidisciplinary disease management plan (DMP) can reduce morbidity and mortality, save costs and improve the quality of life. In Austria, three HF-specific DMPs are currently in a project phase and four established DMPs are active. Although programs are widely heterogeneous with respect to their intervention type, they pursue the same interventional goal by supporting seamless care between inpatient and community care settings with a multidisciplinary team. This survey presents a systematic survey of the HF-specific DMPs in Austria. Disparities between programs are highlighted and discussed. The nationwide establishment of HF-specific DMPs that integrate primary care and cardiology services including a regulation of the remuneration of stakeholders and program infrastructure is needed to decrease the burden of HF for both the individual and society.