bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of cryogenic mixed-refrigerant cooled current leads in combination with peltier elements
Authors: Shabagin E , Raczka K , Grohmann S 
Published: June 2020

Abstract
Current leads supply electrical energy from a room-temperature power supply to a superconducting application, representing thus a major thermal load. State-of-the-art cooling solutions use either open (vapor cooled) or multi-stage closed cycle systems. The multi-stage concept can be integrated in one cryogenic mixed refrigerant cycle (CMRC), where a wide-boiling fluid mixture absorbs the heat load continuously along the current lead. In this paper, we study the combination of CMRC cooling with Peltier elements at the warm end of DC current leads. The Peltier cooling may cause a temperature drop on the order of 80 K. This allows an optimization of the CMRC mixture composition towards lower temperatures, avoiding the use of high-boilers that risk to freeze out at low temperatures. Our studies suggest that Peltier and CMRC cooling can reduce the thermal load at the cold end by 30 to 45% compared to conventional conduction-cooled current leads.
Commissioning of the Cryogenic Phase Equilibria Test Stand CryoPHAEQTS
Authors: Tamson J , Blanck P , Grohmann S 
Published: June 2020

Abstract
Medium-sized cryogenic applications such as local hydrogen liquefaction or HTS power applications require temperatures below 77 K at some kW cooling power. These conditions are efficiently reached by cryogenic mixed refrigerant cycles (CMRC). The CMRC development relies on physical property data of cryogenic fluid mixtures that is not available for most binary and multi-component systems. The cryogenic phase equilibria test stand CryoPHAEQTS provides precise physical property data of cryogenic fluid mixtures at temperatures from 15 K to 300 K and at pressures up to 150 bar. It also allows flammable mixtures (e.g. containing hydrogen) or oxidizing mixtures (e.g. containing oxygen). Vapor-liquid equilibria (VLE), vapor-liquid-liquid equilibria (VLLE) and the liquidus line of solid-liquid equilibria (SLE) are obtained by direct sampling from the equilibrium cell and analysis by gas chromatography. The equilibrium cell offers optical access by 4 windows to identify the coexisting phases. The cell temperature is set by a pulse-tube cryocooler and a counter-heater. As a unique feature, the specific heat capacity of the vapor phase in equilibrium is measured by the combination of a novel thermal and a Coriolis type flow meter. Having measured both caloric and thermal properties of the mixtures, we can develop new equations of state that cover all thermodynamic state variables. In this talk, we report on the progress in the construction and commissioning of CryoPHAEQTS. Validation of the measurement accuracy is presented by comparison of pure substances measurements against literature data.
Performance of MLI Seams between 293 K and 20 K
Authors: Johnson W L , Chato D J 
Published: June 2020

Abstract
The performance of multilayer insulation systems (MLI) are often determined not by the bulk acreage insulation but rather by the design details that allow the insulation to be attached to the hardware it is insulating. To help understand the impacts of multiple different types of seams on blanket performance, calorimeter testing was performed at Glenn Research Center. Seams investigated included interleaved seams, butt seams, and overlapped seams; the latter two types of seams with multiple sub-blanket offsets built into the seam. Results showed that the interleaved seam had the best performance, and butt seams outperformed overlapped seams. Furthermore, if overlap seams are used, the sub-blankets should be overlapped by less than two inches.
Effect of layer thickness on structural, morphological and superconducting properties of Nb3Sn films fabricated by multilayer sequential sputtering
Authors: Sayeed M N , Pudasaini U , Reece C E , Eremeev G V , Elsayed-Ali H E 
Published: June 2020

Abstract
Superconducting Nb3Sn films can be synthesized by controlling the atomic concentration of Sn. Multilayer sequential sputtering of Nb and Sn thin films followed by high temperature annealing is considered as a method to fabricate Nb3Sn films, where the Sn composition of the deposited films can be controlled by the thickness of alternating Nb and Sn layers. We report on the structural, morphological and superconducting properties of Nb3Sn films fabricated by multilayer sequential sputtering of Nb and Sn films on sapphire substrates followed by annealing at 950 °C for 3 h. We have investigated the effect of Nb and Sn layer thickness and Nb:Sn ratio on the properties of the Nb3Sn films. The crystal structure, surface morphology, surface topography, and film composition were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and energy dispersive X-ray spectroscopy (EDS). The results showed Sn loss from the surface due to evaporation during annealing. Superconducting Nb3Sn films of critical temperature up to 17.93 K were fabricated.
Quantum effects in graphitic materials: Colossal magnetoresistance, Andreev reflections, ferromagnetism, and granular superconductivity
Authors: Gheorghiu N , Ebbing CR , Pierce BT , Haugan TJ 
Published: June 2020

Abstract
Unlike the more common local conductance spectroscopy, nonlocal conductance can differentiate between nontopological zero-energy modes localized around inhomogeneities, and true Majorana edge modes in the topological phase. In particular, negative nonlocal conductance is dominated by the crossed Andreev reflection. Fundamentally, the effect reflects the system’s topology. In graphene, the Andreev reflection and the inter-band Klein tunneling couple electronlike and hole-like states through the action of either a superconducting pair potential or an electrostatic potential. We are here probing quantum phenomena in modified graphitic samples. Four-point contact transport measurements at cryogenic to room temperatures were conducted using a Quantum Design Physical Property Measurement System. The observed negative nonlocal differential conductance Gdiff
probes the Andreev reflection at the walls of the superconducting grains coupled by Josephson effect through the semiconducting matrix. In addition, Gdiff
shows the butterfly shape that is characteristic to resistive random-access memory devices. In a magnetic field, the Andreev reflection counters the effect of the otherwise lowered conduction. At low temperatures, the magnetoresistance shows irreversible yet strong giant oscillations that are known to be quantum in nature. In addition, we have found evidence for seemingly granular superconductivity. Thus, graphitic materials show potential for quantum electronics applications, including rectification and topological states.
Methodology to define an integration process between frameworks SCRUM, Django REST framework y Vue.js, implemented for software development, from quality management approach and agility
Authors: Arévalo J G , Viecco L , Arévalo L 
Published: June 2020

Abstract
At present, the industry has great challenges for the construction and maintenance of software, in terms of quality, costs and time, for this it is significant to have a methodological framework, which allows the possibility of having effective and practical methods, applying programming techniques from an agile approach, which guarantees the construction of quality code from the beginning of software development. This study analyzes the integration between frameworks SCRUM [1], Django REST framework [2] and Vue.js [3], which are commonly implemented in isolation for the execution of software development projects, and components are also incorporated of the IEEE 830 standard defined for the specification of software requirements [4], and of the ISO 25000 standard for software quality assessment [5]. Likewise, the characteristics of each study framework within the software architecture are analyzed, establishing of traceability between them and obtaining as a result a methodology for the definition of a process map; where each framework is integrated and it is described the procedure for structuring the planning, development and delivery phases. Thus providing a guide for the application of programming techniques from the concept of agility and quality management, from the process of integration of the frameworks analyzed in this study.
Energy performance analysis between two air conditioning systems used in an educational Building in warm-climate
Authors: Balbis-Morejón M , Silva-Ortega J I , Castro-Peña J 
Published: June 2020

Abstract
Energy saving measures, in the design air conditioning systems, are crucial in the development of energy schemes with rational energy consumption. Traditionally, integrated buildings systems have been assessed individually to optimize the energy performance, however they have different parameters that affect energy performance that demands the use of detailed analysis using dynamic simulation. This paper is focused on compare an air conditioning system to be implemented in educational buildings in warm-climate, considering energy schemes provide for a constant air volume (CAV) flow system with a water chiller, while the other integrates a variable refrigerant flow (VRF) system. Adding in each case dedicated outdoor air System (DOAS) units. Energy consumption achieved by each AC system is obtained considering the configuration achieving energy savings of 40% of the annual electricity demand for cooling. Finally, the use of DOAS represents an increase of 20% of total electricity consumption.
Ultrasonic signal acquisition system for TOFD imaging
Authors: Casagua J , Rodríguez J , Segura D 
Published: June 2020

Abstract
This article describes the development of an application to capture and process ultrasonic signals that will lead to the formation of flight time diffraction images, TOFD. In this way the theoretical basis of operation of this technique is presented establishing concepts such as type A and type D scanning. In addition, the ultrasonic waveforms that are used in this technique are presented. Application development is carried out through layered programming, which consists of three modules: information capture, information storage and finally data processing and graphing. However, the ultrasonic signal acquisition system designed and implemented in the laboratories of the Santo Tomás University of Bogotá D.C is presented as an alternate ultrasound system. For the verification of the system an exploration is carried out on a steel specimen that intentionally contains a hole inside it and the system determines its existence. In addition, a scan is performed on a steel sample with a weld bead and defects within the bead are verified.
Location of Quality Parameters in Small Smart Grid: Off-Grid Case Using Wavelet Transform
Authors: Rojas L. , Rojas C. , Pacheco C. , Caballero E. , Molina M. 
Published: June 2020

Abstract
In the following work the analysis made to an electrical signal by means of wavelet toolbox will be shown. The analysis will be done contemplating the use of the Discrete Wavelet Transform (DWT). This will show the multilevel decomposition taking into account different orders of daubechies. Taking into account the different levels it is expected to show the variants in terms of energetic quality such as sag, swell and harmonic detection. The final work will link the work of digital signal processing with previous work where the construction of a prototype solar system will be explained to obtain the electrical signals of voltage, current and power consumed. In this introductory stage will show the step-by-step development that was taken into account to carry out the design and construction of smart grid scale prototype with AC and DC load control through the HMI interface with LabVIEW software. The design process of the off-grid solar system was carried out through 7 stages that framed the scale of the solar installation. Once the design of the sizing was finished, programming was carried out in Human Machine Interface (HMI) graphics environment with LabVIEW software for optimal control of AC and DC variable loads. This control was established through current relays from 5 volts to 110 volts AC and 5 volts to 12 volts DC. The control interface was made through an embedded board with NI-VISA communication. It is important to note that the smart grid control prototype “Smart Grid” shows optimal results in its operation; denoting this that from the optics of the programming done in the graphics environment, the control of loads dependent on control canter’s; act at disposition. Redundant this in improvements for the energy consumption derived from the storage system under the autonomy designed for three days.
Risk factors for myocardial injury and death in patients with COVID-19: insights from a cohort study with chest computed tomography
Authors: Ferrante Giuseppe , Fazzari Fabio , Cozzi Ottavia , Maurina Matteo , Bragato Renato , D’Orazio Federico , Torrisi Chiara , Lanza Ezio , Indolfi Eleonora , Donghi Valeria , Mantovani Riccardo , Liccardo Gaetano , Voza Antonio , Azzolini Elena , Balzarini Luca , Reimers Bernhard , Stefanini Giulio G , Condorelli Gianluigi , Monti Lorenzo 
Published: June 2020

Abstract

Aims
Whether pulmonary artery (PA) dimension and coronary artery calcium (CAC) score, as assessed by chest computed tomography (CT), are associated with myocardial injury in patients with coronavirus disease 2019 (COVID-19) is not known. The aim of this study was to explore the risk factors for myocardial injury and death and to investigate whether myocardial injury has an independent association with all-cause mortality in patients with COVID-19.

Methods and Results
This is a single-centre cohort study including consecutive patients with laboratory-confirmed COVID-19 undergoing chest CT on admission. Myocardial injury was defined as high-sensitivity troponin I &gt;20 ng/L on admission. A total of 332 patients with a median follow-up of 12 days were included. There were 68 (20.5%) deaths; 123 (37%) patients had myocardial injury. PA diameter was higher in patients with myocardial injury compared with patients without myocardial injury [29.0 (25th–75th percentile, 27–32) mm vs. 27.7 (25–30) mm, P &lt; 0.001). PA diameter was independently associated with an increased risk of myocardial injury [adjusted odds ratio 1.10, 95% confidence interval (CI) 1.02–1.19, P = 0.01] and death [adjusted hazard ratio (HR) 1.09, 95% CI 1.02–1.17, P = 0.01]. Compared with patients without myocardial injury, patients with myocardial injury had a lower prevalence of a CAC score of zero (25% vs. 55%, P &lt; 0.001); however, the CAC score did not emerge as a predictor of myocardial injury by multivariable logistic regression. Myocardial injury was independently associated with an increased risk of death by multivariable Cox regression (adjusted HR 2.25, 95% CI 1.27–3.96, P = 0.005). Older age, lower estimated glomerular filtration rate, and lower PaO2/FiO2 ratio on admission were other independent predictors for both myocardial injury and death.

Conclusions
An increased PA diameter, as assessed by chest CT, is an independent risk factor for myocardial injury and mortality in patients with COVID-19. Myocardial injury is independently associated with an approximately two-fold increased risk of death.
Rape, Victimization, and Agency in Fang Siqi’s Paradise of First Love
Authors: Shen Lisa Chu 
Published: June 2020

Abstract
This article undertakes a feminist analysis of rape in the semi-autobiographical novel Fang Siqi’s Paradise of First Love (“房思琪的初恋乐园” / “Fang Siqi de chulian leyuan”) by Taiwanese author Lin Yihan (林奕含). For Siqi, the traumatic experience of rape intertwines with a discourse of love, interpreted as an effort to disavow victimization and claim agency. A major strength of the novel is the way depictions of personal tragedies are accompanied by lucid exposures of rape as a decidedly social act, which shifts the conventional focus of rape narratives from victims to perpetrators and, in so doing, interrogates the victim-blaming culture and places the responsibility on both social factors and individual perpetrators. In the end, the novel identifies women’s bonding and collective resistance as an effective site for hope and agency.
What drives competition on the farmland market? A case study in Brittany (France)
Authors: Piet Laurent , Melot Romain , Diop Soukeyna 
Published: June 2020

AbstractWe investigate factors which may drive the number of agents who compete for a specific piece of farmland in the French region of Brittany by fitting count models to data originating from a local committee, the CDOA, which is responsible for guidance in delivering the necessary “authorisations to farm”. Results are analysed in the light of a conceptual framework which provides an explanation why the subset of farmers who actually apply for an authorisation to farm may differ from the whole set of potential applicants. Several results reflect the impact of an informal mediation by local farmer unions, which aims to lower potential conflicts and hence competition.
The Effects of Premature Tooth Extraction and Damage on Replacement Timing in the Green Iguana
Authors: Brink Kirstin S , Wu Ping , Chuong Cheng-Ming , Richman Joy M 
Published: June 2020

Synopsis
Reptiles with continuous tooth replacement, or polyphyodonty, replace their teeth in predictable, well-timed waves in alternating tooth positions around the mouth. This process is thought to occur irrespective of tooth wear or breakage. In this study, we aimed to determine if damage to teeth and premature tooth extraction affects tooth replacement timing long-term in juvenile green iguanas (Iguana iguana). First, we examined normal tooth development histologically using a BrdU pulse-chase analysis to detect label-retaining cells in replacement teeth and dental tissues. Next, we performed tooth extraction experiments for characterization of dental tissues after functional tooth (FT) extraction, including proliferation and β-Catenin expression, for up to 12 weeks. We then compared these results to a newly analyzed historical dataset of X-rays collected up to 7 months after FT damage and extraction in the green iguana. Results show that proliferation in the dental and successional lamina (SL) does not change after extraction of the FT, and proliferation occurs in the SL only when a tooth differentiates. Damage to an FT crown does not affect the timing of the tooth replacement cycle, however, complete extraction shifts the replacement cycle ahead by 4 weeks by removing the need for resorption of the FT. These results suggest that traumatic FT loss affects the timing of the replacement cycle at that one position, which may have implications for tooth replacement patterning around the entire mouth.
Optimal rate of convergence for two classes of schemes to stochastic differential equations driven by fractional Brownian motions
Authors: Hong Jialin , Huang Chuying , Wang Xu 
Published: June 2020

Abstract
This paper investigates numerical schemes for stochastic differential equations driven by multi-dimensional fractional Brownian motions (fBms) with Hurst parameter $H\in (\frac 12,1)$. Based on the continuous dependence of numerical solutions on the driving noises, we propose the order conditions of Runge–Kutta methods for the strong convergence rate $2H-\frac 12$, which is the optimal strong convergence rate for approximating the Lévy area of fBms. We provide an alternative way to analyse the convergence rate of explicit schemes by adding ‘stage values’ such that the schemes are interpreted as Runge–Kutta methods. Taking advantage of this technique the strong convergence rate of simplified step-$N$ Euler schemes is obtained, which gives an answer to a conjecture in Deya et al. (2012) when $H\in (\frac 12,1)$. Numerical experiments verify the theoretical convergence rate.
The care and keeping of clinicians in quality improvement
Authors: Shaikh Ulfat , Lachman Peter , Padovani Andrew J , McCarthy SiobhÁn E 
Published: June 2020

Abstract

Objective
Although frontline clinicians are crucial in implementing and spreading innovations, their engagement in quality improvement remains suboptimal. Our goal was to identify facilitators and barriers to the development and engagement of clinicians in quality improvement.

Design
A 25-item questionnaire informed by theoretical frameworks was developed, tested and disseminated by email.

Settings
Members and fellows of the International Society for Quality in Healthcare.

Participants
1010 eligible participants (380 fellows and 647 members).

Interventions
None.

Main Outcome Measures
Self-efficacy and effectiveness in conducting and leading quality improvement activities.

Results
We received 212 responses from 50 countries, a response rate of 21%. Dedicated time for quality improvement, mentorship and coaching and a professional quality improvement network were significantly related to higher self-efficacy. Factors enhancing effectiveness were dedicated time for quality improvement, multidisciplinary improvement teams, professional development in quality improvement, ability to select areas for improvement and organizational values and culture. Inadequate time, mentorship, organizational support and access to professional development resources were key barriers. Personal strengths contributing to effectiveness were the ability to identify problems that need to be fixed, reflecting on and learning from experiences and facilitating sharing of ideas. Key quality improvement implementation challenges were adopting new payment models, demonstrating the business case for quality and safety and building a culture of accountability and transparency.

Conclusions
Our findings highlight areas that organizations and professional development programs should focus on to promote clinician development and engagement in quality improvement. Barriers related to training, time, mentorship, organizational support and implementation must be concurrently addressed to augment the effectiveness of other approaches.
Diversity, abundance, and life histories of littoral chydorids (Cladocera: Chydoridae) in a subarctic European lake
Authors: Klemetsen Anders , Aase Berit M , Amundsen Per-Arne 
Published: June 2020

Abstract
Littoral chydorids were sampled with a bottom sledge in Takvatn, a 15 km2 north Norwegian oligotrophic lake with poor vegetation. Three out of eight recorded species of chydorids were common, with abundance minima in late summer and maxima in autumn. Eurycercus lamellatus (O.F. Müller, 1776) and Acroperus harpae (Baird, 1835) were monocyclic, whereas Chydorus sphaericus (O.F. Müller, 1776) was seemingly acyclic. Females of E. lamellatus appeared in early June and grew to maximum sizes of 2–2.5 mm in early August. Parthenogenesis started in late July and two summer generations could be distinguished by size distributions. Gamogenesis took place in September. Acroperus harpae females appeared in early June and grew to maximum sizes of around 0.7 mm in early August. Parthenogenesis started in early July and gamogenesis took place in September and October. Parthenogenetic females of C. sphaericus appeared already at ice-break and had constant sizes of around 0.4 mm through the entire season. Males or ephippial females were not observed. The acyclic life history may be an adaptation to the challenging environment of this subarctic lake. Summer generations could not be distinguished in the two small-sized species, but both populations reached high abundances in autumn. The abundance of E. lamellatus increased from August, but then decreased, possibly as a result of fish predation. We argue that the present results are typical for large oligotrophic lakes in subarctic Europe.