bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulation of the structural behavior of a Francis runner in Deep Part Load Operation
Authors: von Locquenghien F , Wack J , Conrad P , Jester-Zürker R , Riedelbauch S 
Published: June 2021

Abstract
With the need for flexible operation, Francis runners are exposed to various operating conditions beyond the traditional operating range. These machines have to be designed for long time Part Load Operation in order to meet hydraulic and structural requirements. Deep Part Load Operation (DPL) mainly consists of stochastic loads on the blades. Whereas calculation methods for the dynamic stress at full load operation are well established, calculation of the dynamics during low load operation are in the focus of current research to increase the prediction accuracy. An unsteady flow simulation has been performed for a deep part load operating condition with the goal to derive the time-dependent pressure distribution in the runner. Based on the results, a FEA simulation with a 360° model is performed for multiple time steps to calculate the structural behavior. For a subsequent comparison to a strain gauge measurement, relevant characteristics with regard to material fatigue are identified. In addition, the calculation time in relation to the accuracy of the main characteristics of the flow induced stresses will be discussed.
Vortex rope mitigation with azimuthal perturbations: A numerical study
Authors: Holmström H , Sundström J , Cervantes M J 
Published: June 2021

Abstract
A novel method to mitigate the rotating vortex rope is investigated numerically on a propeller turbine using ANSYS CFX. Pulsating momentum is injected in a horizontal plane in the diffuser cone from four evenly spaced jets. Three mitigation strategies are tested; M1 in which the momentum is injected perpendicular to the axial flow direction, M2, which exhibit a 12 degree angle against the tangential velocity in the diffuser cone, and finally M3, which exhibit the same horizontal angle as M2 but at a 15 % higher flow rate. It is shown that mitigation attempts M1, M2 and M3 decrease the amplitude of the rotating mode by 51%,96% and 97%, respectively. The amplitude of the plunging mode, on the other hand, increase for all mitigation attempts. However, the amplitude of the plunging mode of the unperturbed RVR is an order of magnitude smaller than the rotating mode, and thus, the overall amplitude of the pressure fluctuations in the diffuser decreases significantly. The more efficient mitigation using attempt M2 and M3 are explained using velocity contour in the diffuser cone, which show that the RVR is significantly reduced downstream of the injection plane in between injections, which is not the case for attempt M1.
Dynamics of pressure pulsations in thin annular gap
Authors: Kůrečka Jan , Himr Daniel , Habán Vladimír 
Published: June 2021

Abstract
Fluid pulsations can significantly influence behavior of bearings or sealing parts of hydraulic machines and therefore their operation. In this contribution, an analytical approach to solve pressure pulsations dynamics is compared with a computational solution using acoustic simulation in ANSYS Mechanical FEM package. Studied problem is simplified to an annular gap and the pressure pulsations are excited either from one annulus end or excitation is made by a movement of an inner cylindrical surface perpendicularly to its axis. Excitation on an annulus surface can have angle dependent phase. This geometry allows a linearization of governing equations and so the equations are solvable analytically. Compressibility was incorporated to analytical and computational approach so the eigen frequencies for both methods were evaluated and compared. Also the added fluid effects were studied and evaluated.
Quantifying the Effect of Kaplan-Type Runner Blade Gaps on Fish-related Flow Conditions
Authors: Romero-Gomez Pedro , Colotelo Alison , Weissenberger Simon 
Published: June 2021

Abstract
In double-regulated Kaplan turbines, gaps form between the rotating blade and the hub as well as the discharge ring due to both the local geometry and the operational positioning of the runner blade. It is conventionally assumed that minimizing such gaps may decrease the likelihood of grinding and exposure of fish to high shear flows. Together with blunt leading edges of runner blades, minimum gap runners (MGR) are featured as the most effective measure to ameliorate the risks of mortal injury for fish passing through the turbine. However, the merits of such premise need yet to be quantified and made publicly accessible in the technical literature. This, in turn, will facilitate the evaluation of candidate MGR geometries in future designs.
In this work, we propose a metric to quantify the influence of the gaps features on the mortality risks for fish passing the turbine runner. Two main outcomes derived from the present research: (1) It informs the minimum set of hydraulic variables that may be considered as test conditions for laboratory experimentation on fish subjected to near gap-like flows and (2) it formulates a metric to be integrated into the modelling strategies currently in use for the biological performance assessment of new turbine geometries. This physics-based examination of the flow phenomena was conducted in two Kaplan-type units of very distinct features (one is a very low-head, mid-size unit of 1.8 MW-rating capacity and another is a large-size unit of 90 MW-rating capacity).
Numerical Simulation and Experimental Verification of Downstream Fish migration in a Kaplan turbine
Authors: Benigni H , Schneider J , Reckendorfer W , Jaberg H , Zenz G , Tuhtan J 
Published: June 2021

Abstract
Fish migrating downstream may face an increased risk of injury when passing through hydropower turbines. The overall influence on fish populations remains unknown. Still, it is undoubtedly linked to the damage potential of the turbines, the stage of maturity and the size of the migrating individuals as well as the proportion of migrating fish in relation to the total population. The sources of injury are usually the contact to the turbine blade and the rapid pressure drop in the turbine as well as shear forces, and large-scale turbulence. The authors investigated the conditions experienced by fish migrating through a 5-bladed vertical Kaplan turbine, each of the two units with a nominal power of 45 MW. Therefore, so-called “Barotrauma Detection Sensors (BDS)” were applied to determine the physical parameters during the turbine passages. Additionally, live fish, fitted externally with Barotrauma Detection Sensors, were introduced.
An experimental platform of variable speed pumped storage unit under wave disturbance: introduction and preliminary progress
Authors: Yang Weijia , Yang Jiandong , Zeng Wei , Zhao Zhigao , Zheng Guiqiao , Peng Tao , Huang Yifan , Hu Jinhong , Zeng Zhenyu , Yang Jiebin , Wang Xuewu , Chen Man 
Published: June 2021

Abstract
The importance of pumped storage plants (PSPs) is continuously increasing in power systems with more and more variable renewable energies. For the research and development of PSPs, variable speed technology and sea-water PSP are two important new orientations. In this paper, an experimental platform of variable speed pumped storage unit under wave disturbance is introduced. The purpose of the platform is to study the design and operation mechanism of variable speed PSP based on various common technical problems, especially for the four aspects: transient processes, variable speed unit, coordination control, wave disturbance. The platform adopts a Chinese sea-water PSP in feasibility stage as the prototype, and a model scale of 1:4 is applied. It consists of nine sub-systems, including waterway system, variable speed reversible model unit, circulating water system, speed governor system, AC excitation and electric protection, coordination control, monitoring system, intelligent AC load and measurement system. The model unit contains a reversible pump turbine, a doubly fed induction machine, etc. The speed variation range is ±8%, and the rated power is 78.13 kW. The model runner meets the IEC standard with a reference diameter of 284.3 mm. The upstream water tank is a closed pressure tank that can adjust the pressure and discharge. The downstream water tank is an open water tank that can simulate wave level fluctuation. Regarding the control system, it has four core parts: local control unit, speed governor, converter and coordination controller. The experimental study content contains three key aspects: (1) performance validation for variable speed unit; (2) operating stability under complex disturbances; (3) capability of variable speed PSP during transient processes. The experimental study based on the platform aims for laying a theoretical and technical foundation for the follow-up construction and operation of real sea-water PSPs with variable speed units.
Analysis of dynamic performance in a pump-turbine during the successive load rejection
Authors: Bi Huili , Chen Funan , Wang Chao , Wang Zhengwei , Fan Honggang , Luo Yongyao 
Published: June 2021

Abstract
Successive load rejection is one of the most crucial transient processes for calculating the maximum pressure in spiral case and maximum rotating speed of runner. One-dimensional mathematical models were established for a pump-storage power station and characteristics method was used to study the successive load rejection. The condition in which the maximum pressure occurs was chosen for three-dimensional unsteady calculation. The boundary conditions at spiral-casing inlet and draft tube outlet were determined by using the one-dimensional result. Based on numerical simulation, the axial hydraulic thrust and transient flow characteristic during the successive load rejection process were analysed. The axial hydraulic thrust during the successive load rejection process was mainly caused by the complex flow in the runner. The complex flow was affected both by hydraulic disturbance and the successive load rejection process.
DISMIR:

D

eep learning-based noninvasive cancer detection by

i

ntegrating DNA

s

equence and methylation information of

i

ndividual cell-free DNA

r

eads
Authors: Li Jiaqi , Wei Lei , Zhang Xianglin , Zhang Wei , Wang Haochen , Zhong Bixi , Xie Zhen , Lv Hairong , Wang Xiaowo 
Published: June 2021

Abstract
Detecting cancer signals in cell-free DNA (cfDNA) high-throughput sequencing data is emerging as a novel noninvasive cancer detection method. Due to the high cost of sequencing, it is crucial to make robust and precise predictions with low-depth cfDNA sequencing data. Here we propose a novel approach named DISMIR, which can provide ultrasensitive and robust cancer detection by integrating DNA sequence and methylation information in plasma cfDNA whole-genome bisulfite sequencing (WGBS) data. DISMIR introduces a new feature termed as ‘switching region’ to define cancer-specific differentially methylated regions, which can enrich the cancer-related signal at read-resolution. DISMIR applies a deep learning model to predict the source of every single read based on its DNA sequence and methylation state and then predicts the risk that the plasma donor is suffering from cancer. DISMIR exhibited high accuracy and robustness on hepatocellular carcinoma detection by plasma cfDNA WGBS data even at ultralow sequencing depths. Further analysis showed that DISMIR tends to be insensitive to alterations of single CpG sites’ methylation states, which suggests DISMIR could resist to technical noise of WGBS. All these results showed DISMIR with the potential to be a precise and robust method for low-cost early cancer detection.
Detecting copy number alterations in RNA-Seq using SuperFreq
Authors: Flensburg Christoffer , Oshlack Alicia , Majewski Ian J 
Published: June 2021

Abstract

Motivation
Calling copy number alterations (CNAs) from RNA sequencing (RNA-Seq) is challenging, because of the marked variability in coverage across genes and paucity of single nucleotide polymorphisms (SNPs). We have adapted SuperFreq to call absolute and allele sensitive CNAs from RNA-Seq. SuperFreq uses an error-propagation framework to combine and maximize information from read counts and B-allele frequencies.

Results
We used datasets from The Cancer Genome Atlas (TCGA) to assess the validity of CNA calls from RNA-Seq. When ploidy estimates were consistent, we found agreement with DNA SNP-arrays for over 98% of the genome for acute myeloid leukaemia (TCGA-AML, n = 116) and 87% for colorectal cancer (TCGA-CRC, n = 377). The sensitivity of CNA calling from RNA-Seq was dependent on gene density. Using RNA-Seq, SuperFreq detected 78% of CNA calls covering 100 or more genes with a precision of 94%. Recall dropped for focal events, but this also depended on signal intensity. For example, in the CRC cohort SuperFreq identified all cases (7/7) with high-level amplification of ERBB2, where the copy number was typically &gt;20, but identified only 6% of cases (1/17) with moderate amplification of IGF2, which occurs over a smaller interval. SuperFreq offers an integrated platform for identification of CNAs and point mutations. As evidence of how SuperFreq can be applied, we used it to reproduce the established relationship between somatic mutation load and CNA profile in CRC using RNA-Seq alone.

Availability and implementation
SuperFreq is implemented in R and the code is available through GitHub: https://github.com/ChristofferFlensburg/SuperFreq/. Data and code to reproduce the figures are available at: https://gitlab.wehi.edu.au/flensburg.c/SuperFreq_RNA_paper. Data from TCGA (phs000178) was accessed from GDC following completion of a data access request through the database of Genotypes and Phenotypes (dbGaP). Data from the Leucegene consortium was downloaded from GEO (AML samples: GSE67040; normal CD34+ cells: GSE48846).

Supplementary information
Supplementary data are available at Bioinformatics online.
Nestling behaviour predicts naris deformation in Darwin’s finches parasitized by the avian vampire fly
Authors: Katsis Andrew C , Colombelli-Négrel Diane , Common Lauren K , O’connor Jody A , Dudaniec Rachael Y , García-Loor Jefferson , Kleindorfer Sonia 
Published: June 2021

Abstract
Although in-nest parasitism can reduce the fitness of avian hosts, the severity of these effects may vary with host physiology and behaviour. If certain nestling behaviours are beneficial for resisting parasitism, then selection may favour some behavioural phenotypes over others. Here, we tested whether differences in nestling behaviour mediate the negative effects of parasitism, using small ground finches (Geospiza fuliginosa), on Floreana Island, that had been parasitized by the invasive avian vampire fly (Philornis downsi). We first established, using 4 years of breeding data (2005, 2006, 2010 and 2020), that nestlings exposed to more parasites had larger nares and, among older nestlings only, lower body mass. We then examined, using data from the 2020 season, whether each nestling’s behaviour (specifically, its response to human handling) predicted the severity of its naris deformation. When faced with high-intensity parasitism, more responsive nestlings (i.e. those that struggled more during handling) had larger nares compared to more docile nestlings. This suggests that more responsive nestlings suffer greater fitness costs due to parasitism, although we also discuss alternative explanations. Future work should consider the stability and heritability of these nestling behavioural differences and whether parasite-induced selection shapes behavioural variation at the population level.
Risk of Symptomatic Infection During a Second Coronavirus Disease 2019 Wave in Severe Acute Respiratory Syndrome Coronavirus 2–Seropositive Individuals
Authors: Manica Mattia , Pancheri Serena , Poletti Piero , Giovanazzi Giulia , Guzzetta Giorgio , Trentini Filippo , Marziano Valentina , Ajelli Marco , Grazia Zuccali Maria , Benetollo Pier Paolo , Merler Stefano , Ferro Antonio 
Published: June 2021

Abstract
We analyzed 221 coronavirus disease 2019 cases identified between June 2020 and January 2021 in 6074 individuals screened for immunoglobulin G antibodies in May 2020, representing 77% of residents of 5 Italian municipalities. The relative risk of developing symptomatic infection in seropositive participants was 0.055 (95% confidence interval, .014–.220).
Discovery of a first-in-class inhibitor of sulfide:quinone oxidoreductase that protects against adverse cardiac remodelling and heart failure
Authors: Jackson Michael R , Cox Kristie D , Baugh Simon D P , Wakeen Luke , Rashad Adel A , Lam Patrick Y S , Polyak Boris , Jorns Marilyn Schuman 
Published: June 2021

Abstract

Aims
Hydrogen sulfide (H2S) is a potent signalling molecule that activates diverse cardioprotective pathways by post-translational modification (persulfidation) of cysteine residues in upstream protein targets. Heart failure patients with reduced ejection fraction (HFrEF) exhibit low levels of H2S. Sulfide:quinone oxidoreductase (SQOR) catalyses the first irreversible step in the metabolism of H2S and plays a key role in regulating H2S-mediated signalling. Here, the aim of this study was to discover a first-in-class inhibitor of human SQOR and evaluate its cardioprotective effect in an animal model of HFrEF.

Methods and results
We identified a potent inhibitor of human SQOR (STI1, IC50 = 29 nM) by high-throughput screening of a small-molecule library, followed by focused medicinal chemistry optimization and structure-based design. STI1 is a competitive inhibitor that binds with high selectivity to the coenzyme Q-binding pocket in SQOR. STI1 exhibited very low cytotoxicity and attenuated the hypertrophic response of neonatal rat ventricular cardiomyocytes and H9c2 cells induced by neurohormonal stressors. A mouse HFrEF model was produced by transverse aortic constriction (TAC). Treatment of TAC mice with STI1 mitigated the development of cardiomegaly, pulmonary congestion, dilatation of the left ventricle, and cardiac fibrosis and decreased the pressure gradient across the aortic constriction. Moreover, STI1 dramatically improved survival, preserved cardiac function, and prevented the progression to HFrEF by impeding the transition from compensated to decompensated left ventricle hypertrophy.

Conclusion
We demonstrate that the coenzyme Q-binding pocket in human SQOR is a druggable target and establish proof of concept for the potential of SQOR inhibitors to provide a novel therapeutic approach for the treatment of HFrEF.
Simple View of Reading in Deaf and Hard-of-Hearing Adults
Authors: Wauters Loes , van Gelder Hille , Tijsseling Corrie 
Published: June 2021

Abstract
The present study investigated the relative contribution of the two components in the simple view of reading to the reading comprehension skills of deaf and hard-of-hearing (DHH) adults in the Netherlands. Eighty DHH adults, aged between 30 and 80 years old, were tested on word reading, reading fluency, vocabulary, and reading comprehension. Regression analyses showed that both decoding skills and vocabulary contributed to the reading comprehension skills of DHH adults, with vocabulary being the strongest predictor. For skilled decoders, the picture was somewhat different with only vocabulary being a predictor of reading comprehension. The results of this study show that the simple view of reading is applicable to DHH adults’ reading comprehension skills: both decoding skills and vocabulary contribute to reading comprehension. Also, as in previous studies on the simple view of reading, as readers become more skilled in the decoding process, vocabulary becomes the only predictor of reading comprehension.
Effect of Photoperiod on Longevity, Food Consumption, and Reproduction ofHolotrichia oblita(Coleoptera: Scarabaeidae)
Authors: Xie Ming-hui , Zhong Yong-zhi , Lin Lu-lu , Zhang Guang-ling , Su Wei-hua , Ni Wan-Li , Qu Ming-jing , Chen Hao-liang 
Published: June 2021

AbstractHolotrichia oblita (Faldermann) (Coleoptera: Scarabaeidae) is a major soil insect pest that damages forest trees, crops, and lawns. Adults of H. oblita fly, forage, and mate at night but remain underground during the day. We studied the effect of photoperiod on H. oblita reproduction. H. oblita females laid more eggs at 8:16 (L:D) h and 0:24 (L:D) h than other photoperiods. As the scotophase increased, the preoviposition period decreased and the oviposition period increased. Female longevity exceeded that of males at all photoperiods, and both males and females at 0:24 (L:D) h had the shortest longevity. The number of eggs laid per female increased with increasing food consumption. Females at 8:16 (L:D) h had the greatest food consumption and laid the most eggs, while females at 24:0 (L:D) h had the lowest food consumption and laid few eggs. The food intake of adults increased gradually and decreased slowly after reaching a peak. Females began to lay eggs when their food consumption reached a maximum. These results indicate that a scotophase is necessary for the reproduction of H. oblita. A long scotophase promotes greater oviposition. The effect of photoperiod on reproduction is affected by food intake.
Causes of hospitalization in the USA between 2005 and 2018
Authors: Salah Husam M , Minhas Abdul Mannan Khan , Khan Muhammad Shahzeb , Pandey Ambarish , Michos Erin D , Mentz Robert J , Fudim Marat 
Published: June 2021

Abstract
In this report, we identify the 10 most common causes of hospitalizations in the USA in 2005–2018 using the discharge data from the National Inpatient Sample database. We show that sepsis has been the leading cause of hospitalizations in the USA followed by heart failure, which has consistently been within the three most common causes of hospitalizations since 2005. In addition, we show a high burden of cardiovascular diseases as a cause of hospitalization over the study period with a consistent presence of cardiac arrhythmias as one of the top 10 causes of hospitalizations in the USA and emergence of acute myocardial infarction as one of the top 10 causes after 2014.
Implications of the Diversity of the Rules on the Use of Force for Change in the Law
Authors: Akande Dapo , Johnston Katie A 
Published: June 2021

Abstract
This article analyses the structural conditions within the jus ad bellum that affect whether and how that law changes. In particular, it examines how the diversity of the rules that form the law relating to the use of force affects the development of rules permitting the use of force to protect human rights. After noting some areas where it has been argued that aspects of the law relating to use of force have changed as a result of evolving state practice, it identifies a number of obstacles to accepting the argument that changes to customary international law can affect the law on the use of force in the UN Charter. It is argued that, unlike with self-defence, changes to customary international law would not automatically lead to changes in the Charter prohibition of the use of force. Since any rule permitting humanitarian intervention would create a new exception to the Charter prohibition of the use of force and to a norm of jus cogens, that change cannot occur on the basis of custom alone. Changes to interpretations of the UN Charter and to a jus cogens norm will be required, and such changes must occur in line with the rules regarding how such norms change. Finally, the article considers one concrete possibility for a change to the jus ad bellum that would allow humanitarian intervention without UN Security Council approval: approval of such a use of force by the UN General Assembly under the ‘Uniting for Peace’ Resolution of 1950. Leaving aside the political and practical challenges of achieving such change, the section explores the conceptual challenges that would need to be overcome.