bluuebunny/crossref_metadata_2025_split huggingface dataset:
PIV measurements on a Kaplan turbine and comparison with scale-adaptive numerical analysis
Authors: Beck Johannes , Jossberger Simon , Jester-Zürker Roland , Riedelbauch Stefan 
Published: December 2019

Abstract
Kaplan turbines build a mainstay of the hydro power generation as they offer best efficiency even for high flow conditions. A double regulating approach facilitates a high degree of flexibility but yields to be a sophisticated turbine type. Typical phenomena like gap flow and flow separation are challenges in simulation and complicate reliable predictions. To get a better understanding of flow physics elaborate numerical simulations by means of Computational fluid dynamics (CFD) are conducted as well as experimental flow investigation using the non-intrusive optical measurement technique Particle Image Velocimetry (PIV). Measurements are taken at the spiral case inlet, the draft tube cone and the diffuser giving instantaneous or phase-locked time averaged vector fields of flow velocity in a plane. Depending on the optical access it is possible to gather the in-plane velocity components or all three velocity components using Stereoscopic PIV. The obtained measurement results are then taken as reference on the one hand side for a definition of realistic inlet boundary condition and on the other hand side for assessment of the chosen numerical approach for predicting flow phenomena in Kaplan turbines. In this particular case the focus is on the interaction of runner and draft tube. Results of unsteady simulations with standard two equation and advanced hybrid RANS-LES turbulence models are compared to measurement data.
Numerical study on pressure fluctuation in a multiphase rotodynamic pump with different inlet gas void fractions
Authors: Zhang W W , Zhu B S , Yu Z Y 
Published: December 2019

Abstract
Pressure fluctuation in the single-phase pump has been widely discussed, while less attention was paid for that in the multiphase pump. Therefore, this study investigated the pressure fluctuation in a multiphase rotodynamic pump. Unsteady simulations based on Euler two-fluid model were done with ANSYS-CFX software when the inlet gas void fractions (IGVFs) were 0.0%, 3.0%, 9.0%, and 15.0%. Under pure water (IGVF=0.0%) and gas-liquid two-phase (IGVFs=3.0%, 9.0%, 15.0%) conditions, the reliability of numerical method was verified by comparison with the experimental data. The numerical results showed that the dominant frequency in the impeller and guide vane corresponded to the blade numbers of guide vane and impeller, respectively. This illustrated that the rotor-stator interaction was the main cause for the generation of fluctuation in such pump. Meanwhile, the maximum fluctuation amplitude appeared near the impeller outlet at IGVF=0.0%, while it appeared near the guide vane inlet under two-phase conditions. Furthermore, the maximum fluctuation amplitudes at IGVF=3.0%, 9.0%, 15.0% are 1.9, 2.9, and 3.3 times as large as that at IGVF=0.0%.
Experimental verification of the effect of gap geometry on the tip-leakage flow pattern and tip-clearance cavitation
Authors: Pervunin Konstantin S , Yu Nichik Mikhail , Timoshevskiy Mikhail V 
Published: December 2019

Abstract
Tip-clearance cavitation is one of the most aggressive and widespread forms of cavitation in hydraulic machinery that occurs due to liquid leaking through narrow gaps between tips or end faces of blades/vanes and a stator wall. The research is aimed at the study of a passive control of tip-leakage flow and tip-clearance cavitation by modifying the gap geometry. The test object was a NACA0022-34 hydrofoil with a 100 mm chord that was equipped with a double-sided axis of rotation. The gap geometry was changed by mounting side plates with different end surfaces (flat and grooved) to the hydrofoil end face. We used high-speed imaging to analyze the temporal and spatial cavity evolution simultaneously on the foil suction side and inside the clearance using three cameras. The implemented control method was shown to allow an effective management of the tip-leakage flow and tip-clearance cavitation, especially at higher angles of attack. The modified end plate makes the tip-leakage flow less prone to cavitation as compared to the original one, i.e. the tip-clearance cavitation inception and development appear to be hampered.
Raman modes and dielectric relaxation properties of epitaxial BaBiO3 thin films
Authors: Talha M , Lee Y W 
Published: December 2019

Abstract
Perovskite BaBiO3 films are grown on MgO (100) substrate and SrTiO3 (001) and (110) substrates using pulsed laser deposition. The thickness of the films ranges from ∼10 nm up to 200 nm. X-ray diffraction and reciprocal space mapping show that the thin films are grown epitaxially but relaxed considerably particularly for the films on SrTiO3. The topography of the film surfaces are obtained with AFM and found to be atomically flat with the step and terrace structure of unit cell step height. Raman spectroscopy is performed on the BaBiO3 films in the temperature range from 50 K to 300 K. The phonon modes related to octahedral breathing, bond bending, and bond stretching are detected in the Raman spectra, and the distinctive features are found in the phonon modes below and above a structural transition around 140 K. Out-of-plane dielectric measurements are also carried out from 10 K to 400 K for the films on SrTiO3 with different orientations. In particular, the dielectric measurements demonstrate frequency as well as orientation dependent anisotropic dielectric relaxation behaviors in BaBiO3 films.
Hygrothermal chamber aging effect on mechanical behavior and morphology of glass fiber-epoxy-nanoclay composites
Authors: Shettar Manjunath , Kini U Achutha , Sharma Sathyashankara , Hiremath Pavan , M C Gowrishankar 
Published: December 2019

Abstract
This work examines the impact of artificial aging on tensile and flexural behavior of epoxy-nanoclay composites (ENCs) and glass fiber-epoxy-nanoclay composites (GFENCs) in the hygrothermal chamber. Epoxy-nanoclay composites made by a general-casting technique, and GFENCs are made by hand layup technique. The specimens are aged in the hygrothermal chamber for 180 days at 40 °C with 60% RH. The results revealed that an increase in nanoclay and glass fiber weight percentage enhanced the mechanical behavior of GFENCs. The aging of the sample has a negative influence on the composite materials. But, the increase in nanoclay and glass fiber weight percentage has diminished the impact of aging on the mechanical behavior of composites. SEM micrographs revealed the reason for the failure and influence of aging conditions.
Oxidation study of CoCrCuFeNiSix high entropy alloys
Authors: Shajahan Shaik , Kumar Anil , Chopkar Manoj , Basu A 
Published: December 2019

Abstract
Oxidation studies of Co–Cr–Cu–Fe–Ni–SiX=(0,0.3,0.6,0.9) high entropy alloys (HEA) at 600, 700 and 800 °C for 30 h are performed in the present work. Isothermal oxidation confirmed that the oxidation resistance of Co–Cr–Cu–Fe–Ni–SiX=(0,0.3,0.6,0.9 ) high entropy alloy increases with Silicon (Si) content up to 0.6%, beyond that it decreases. Oxidation rate kinetics study of all the alloys at the three designated test temperature represented the typical cubic curve. X-ray diffraction (XRD) analysis revealed the evolution of Cu oxide (CuO) along with existing phases in all the HEA samples. Microstructural observation after oxidation test exhibited an increase in oxide formation with the oxidation temperature. To comprehend the kinetics of oxidation more clearly, Arrhenius plots were drawn for all the HEA samples and activation energies are calculated.
An absolute human stemness index associated with oncogenic dedifferentiation
Authors: Zheng Hailong , Song Kai , Fu Yelin , You Tianyi , Yang Jing , Guo Wenbing , Wang Kai , Jin Liangliang , Gu Yunyan , Qi Lishuang , Zhao Wenyuan 
Published: December 2019

Abstract
The progression of cancer is accompanied by the acquisition of stemness features. Many stemness evaluation methods based on transcriptional profiles have been presented to reveal the relationship between stemness and cancer. However, instead of absolute stemness index values—the values with certain range—these methods gave the values without range, which makes them unable to intuitively evaluate the stemness. Besides, these indices were based on the absolute expression values of genes, which were found to be seriously influenced by batch effects and the composition of samples in the dataset. Recently, we have showed that the signatures based on the relative expression orderings (REOs) of gene pairs within a sample were highly robust against these factors, which makes that the REO-based signatures have been stably applied in the evaluations of the continuous scores with certain range. Here, we provided an absolute REO-based stemness index to evaluate the stemness. We found that this stemness index had higher correlation with the culture time of the differentiated stem cells than the previous stemness index. When applied to the cancer and normal tissue samples, the stemness index showed its significant difference between cancers and normal tissues and its ability to reveal the intratumor heterogeneity at stemness level. Importantly, higher stemness index was associated with poorer prognosis and greater oncogenic dedifferentiation reflected by histological grade. All results showed the capability of the REO-based stemness index to assist the assignment of tumor grade and its potential therapeutic and diagnostic implications.
Causal network perturbations for instance-specific analysis of single cell and disease samples
Authors: Buschur Kristina L , Chikina Maria , Benos Panayiotis V 
Published: December 2019

Abstract

Motivation
Complex diseases involve perturbation in multiple pathways and a major challenge in clinical genomics is characterizing pathway perturbations in individual samples. This can lead to patient-specific identification of the underlying mechanism of disease thereby improving diagnosis and personalizing treatment. Existing methods rely on external databases to quantify pathway activity scores. This ignores the data dependencies and that pathways are incomplete or condition-specific.

Results
ssNPA is a new approach for subtyping samples based on deregulation of their gene networks. ssNPA learns a causal graph directly from control data. Sample-specific network neighborhood deregulation is quantified via the error incurred in predicting the expression of each gene from its Markov blanket. We evaluate the performance of ssNPA on liver development single-cell RNA-seq data, where the correct cell timing is recovered; and two TCGA datasets, where ssNPA patient clusters have significant survival differences. In all analyses ssNPA consistently outperforms alternative methods, highlighting the advantage of network-based approaches.

Availability and implementation
http://www.benoslab.pitt.edu/Software/ssnpa/.

Supplementary information
Supplementary data are available at Bioinformatics online.
The (negative) impact of supply-side labour market reforms on productivity: an overview of the evidence1
Authors: Kleinknecht Alfred 
Published: December 2019

AbstractIn spite of impressive stories about artificial intelligence or Industry 4.0, the USA, Japan and Western Europe experience a severe productivity crisis since about 2005. This article fills a gap in recent attempts at understanding the productivity crisis, arguing that there is a negative impact of supply-side labour market reforms on innovation and productivity. The negative impact of more flexible labour relations is significant in medium-high and high-tech sectors with a high ‘cumulativeness’ of knowledge, that is if the historical accumulation of firm-specific and often tacit knowledge is important for innovative competencies. In low-tech sectors as well as for high-tech entrepreneurship, where cumulativeness of knowledge is low, there is little or no effect.
Impact of Diet on Risk of IBD
Authors: Ananthakrishnan Ashwin N 
Published: December 2019

Abstract
Diet is an important factor influencing the pathogenesis of Crohn’s disease (CD) and ulcerative colitis (UC). Several recent prospective cohorts have suggested various dietary factors may play a role in modifying the risk of these diseases. These include an inverse association between dietary fiber, fruit or vegetable intake and risk of CD and n-3 polyunsaturated fatty acids and UC. In addition to macro-nutrients, dietary additives such as emulsifiers may also play a role.
Tax Policy, Foreign Direct Investment and Spillover Effects in Africa

1
Authors: Boly Amadou , Coulibaly Seydou , Kéré Eric N 
Published: December 2019

Abstract
Foreign direct investment (FDI) inflows are crucial for economic development. To attract them, countries have typically used reductions in corporate income tax (CIT) rates. This paper empirically assesses the impact of such CIT rate changes on FDI net inflows in Africa. Using a dynamic spatial Durbin model with fixed effects, our results show that cuts in CIT rates increase FDI net inflows in the host country and in the neighbouring countries in the short and long run. These results are robust to the use of alternative spatial weighting matrices as well as the inclusion of additional controls in the baseline specification. Furthermore, we find a strategic complementarity in FDI inflows between the countries in our sample, suggesting that an increase in FDI inflows in a host country is likely to stimulate FDI inflows of its neighbours.
Effect of low- and high-protein maternal diets during gestation on reproductive outcomes in the rat: a systematic review and meta-analysis
Authors: Ajuogu Peter K , Wolden Mitchell , McFarlane James R , Hart Robert A , Carlson Debra J , Van der Touw Tom , Smart Neil A 
Published: December 2019

AbstractStudies with animal models have consistently demonstrated adverse health outcomes in offspring born following nutritional manipulation during gestation. However, the effects of gestational dietary protein modification on reproductive outcomes at birth are less clear. We, therefore, conducted a systematic review and meta-analysis of controlled trials to determine whether high- or low-protein diets are associated with altered reproductive outcomes in a commonly studied species, the rat. Included studies were identified through a systematic search using electronic databases and manual literature review to identify randomized studies published between June 1972 and March 2019. Thirty-two studies were identified and used to analyze the effects of low- and high-protein gestational diets on litter size, litter weight, gestational weight gain, and gestational feed intake. The results indicate that low-protein diets significantly reduced litter weight (P &lt; 0.00001) and gestational weight gain (P &lt; 0.0006), but did not influence litter size (P = 0.62) or gestational feed intake (P = 0.25). In contrast, high-protein diets were found to reduce gestational feed intake (P = 0.004) but did not influence litter size (P = 0.56), litter weight (P = 0.22), or gestational weight gain (P = 0.35). The results suggest that low but not high-protein gestational diets alter reproductive outcomes at birth in rats.
Targeted Mutations in Xylella fastidiosa Affect Acquisition and Retention by the Glassy-Winged Sharpshooter, Homalodisca vitripennis (Hemiptera: Cicadellidae)
Authors: Sengoda Venkatesan G , Shi Xiangyang , Krugner Rodrigo , Backus Elaine A , Lin Hong 
Published: December 2019

Abstract
Xylella fastidiosa (Wells) is a xylem-limited bacterium that causes Pierce’s disease of grapevines. The bacterium is transmitted by insect vectors such as the glassy-winged sharpshooter (GWSS), Homalodisca vitripennis (Germar). Experiments were conducted to compare the role of selected X. fastidiosa genes on 1) bacterial acquisition and retention in GWSS foreguts, and 2) transmission to grapevines by GWSS. Bacterial genotypes used were: mutants Xf-ΔpilG, Xf-ΔpilH, Xf-ΔgacA, and Xf-ΔpopP; plus wild type (WT) as control. Results showed that Xf-ΔpilG had enhanced colonization rate and larger numbers in GWSS compared with WT. Yet, Xf-ΔpilG exhibited the same transmission efficiency as WT. The Xf-ΔpilH exhibited poor acquisition and retention. Although initial adhesion, multiplication, and retention of Xf-ΔpilH in GWSS were almost eliminated compared with WT, the mutation did not reduce transmission success in grapevines. Overall, Xf-ΔgacA showed colonization rates and numbers in foreguts similar to WT. The Xf-ΔgacA mutation did not affect initial adhesion, multiplication, and long-term retention compared with WT, and was not significantly diminished in transmission efficiency. In contrast, numbers of Xf-ΔpopP were variable over time, displaying greatest fluctuation from highest to lowest levels. Thus, Xf-ΔpopP had a strong, negative effect on initial adhesion, but adhered and slowly multiplied in the foregut. Again, transmission was not diminished compared to WT. Despite reductions in acquisition and retention by GWSS, transmission efficiency of genotypes to grapevines was not affected. Therefore, in order to stop the spread of X. fastidiosa by GWSS using gene-level targets, complete disruption of bacterial colonization mechanisms is required.
Performing Statehood through Crises: Citizens, Strangers, Territory
Authors: Neumann Iver B , Sending Ole Jacob 
Published: December 2019

AbstractThis article applies the growing International Relations literature on state performance and performativity to the question of how practitioners categorize different kinds of crises. The aim is to add value to the crisis literature by paying more attention to how performances are staged for multiple audiences, how statehood is produced as a collective (as opposed to an individual) body, and how and why one and the same state actor performs statehood in different ways. Drawing on interviews and participant observation, we discuss how one state apparatus, the Norwegian Ministry of Foreign Affairs (MFA), performs statehood during different types of crisis. The MFA has institutionalized crisis management in three very different ways, depending on whether it defines the crisis as a security crisis, a humanitarian crisis, or a civilian crisis. Different crises have different audiences, are performed in different repertoires, and produce three different aspects of the state that we name, respectively, caretaking, do-gooding, and sovereignty. Bringing the performativity literature to the study of crises gives us a better understanding of the statecraft that goes into using crises as opportunities to make visible and strengthen the state as a presence in national and global social life. Conversely, our focus on the specificity of various state performances highlights how the performance literature stands to gain from differentiating more clearly between the straightforward performing of practices, on the one hand, and the performing of state identity by means of the same practices, on the other.
Weak, Politicized, Absent: The Anti-Mercenary Norm in Italy and the United Kingdom, 1805–2017
Authors: Casiraghi Matteo C M 
Published: December 2019

Abstract
Addressing the anti-mercenary norm, this article offers an original empirical contribution and a new theoretical framework, where taboo talks, hide-or-justify strategies, and inconsistent behavior define the robustness of a norm. I code and analyze all references to mercenaries and private military companies in the Italian and British parliamentary debates from 1805 to 2017, and I demonstrate that the norm evolves through three critical moments. Between 1805 and 1945, an anti-mercenary moral norm is present to a relevant extent in politicians’ debates, though it does not consistently constrain states’ behavior. The norm is weak. Between 1945 and 1991, anti-mercenary sentiments start to decline, and all discussions about their operations are clearly distorted by Cold War dynamics. The norm is very weak and highly politicized. After 1991, the norm targets security contractors for a brief period, as negative references and moral attacks significantly decrease. The norm disappears.
Pseudoaneurysm of gastroduodenal artery and pulmonary embolism: rare co-incidence of two complications of pancreatitis
Authors: Sgantzou Ioanna Konstantina , Samara Athina A , Diamantis Alexandros , Karagiorgas Georgios P , Zacharoulis Dimitrios , Rountas Christos 
Published: December 2019

Abstract
Preventing and curing complications of acute and chronic pancreatitis, which may be local or systemic, remains a challenge. Pseudocysts and walled-off pancreatic necrosis are two local complications that most frequently require surgical intervention. Two rare complications of pancreatitis are pseudoaneurysms and pulmonary embolism. Angiographic embolization can be the treatment of choice for pseudoaneurysms, while for pulmonary embolism apart from anticoagulation treatment, the optional inferior vena cava filter placement could be useful. As far as we know, in literature, these complications of pancreatitis have never been reported simultaneously yet.
Solar activity cycle of ∼200 yr from mediaeval Korean records and reconstructions of cosmogenic radionuclides
Authors: Chol-jun Kim , Jik-su Kim 
Published: December 2019

ABSTRACTWe have investigated Korean records of naked-eye observations of sunspots and we have found evidence that implies a periodicity of about 200 yr. Adding Chinese records, we show that these historical naked-eye observations of sunspots have a similar periodicity. Recently, some authors have shown that there are no intrinsic periodicities except for the 11-yr cycle. We adopt a new approach called a samplogram to test the sampling stability of cycles in terms of power spectra and difference series. We show that the Suess/de Vries cycle of about 207 yr is a deterministic cycle of stochastic solar activity. Also, we show that occurrences of grand minima are not necessarily expected with the Suess/de Vries cycle and it is possible for double or multiple grand maxima to appear without a grand minimum within them.
Few SINEs of life: Alu elements have little evidence for biological relevance despite elevated translation
Authors: Martinez-Gomez Laura , Abascal Federico , Jungreis Irwin , Pozo Fernando , Kellis Manolis , Mudge Jonathan M , Tress Michael L 
Published: December 2019

Abstract
Transposable elements colonize genomes and with time may end up being incorporated into functional regions. SINE Alu elements, which appeared in the primate lineage, are ubiquitous in the human genome and more than a thousand overlap annotated coding exons. Although almost all Alu-derived coding exons appear to be in alternative transcripts, they have been incorporated into the main coding transcript in at least 11 genes. The extent to which Alu regions are incorporated into functional proteins is unclear, but we detected reliable peptide evidence to support the translation to protein of 33 Alu-derived exons. All but one of the Alu elements for which we detected peptides were frame-preserving and there was proportionally seven times more peptide evidence for Alu elements as for other primate exons. Despite this strong evidence for translation to protein we found no evidence of selection, either from cross species alignments or human population variation data, among these Alu-derived exons. Overall, our results confirm that SINE Alu elements have contributed to the expansion of the human proteome, and this contribution appears to be stronger than might be expected over such a relatively short evolutionary timeframe. Despite this, the biological relevance of these modifications remains open to question.