bluuebunny/crossref_metadata_2025_split huggingface dataset:
Age‐related changes in interstitial fibrosis and germ cell degeneration of the canine testis
Authors: Bhanmeechao Cholayuth , Srisuwatanasagul Sayamon , Ponglowhapan Suppawiwat 
Published: November 2018

ContentsFifty‐five healthy medium‐sized dogs were divided into four groups; young (1–3 years old, n = 14), adult (>3 to 6 years old, n = 12), old (>6 to 9 years old, n = 14) and senile (>9 years old, n = 15). After routine orchiectomy, testes were collected, and the degree of white streak areas on cut surfaces was subjectively assessed. Later, testicular tissue sections were stained with haematoxylin and eosin and Masson's trichrome for evaluation of germ cell degeneration and the proportion of interstitial connective tissue, respectively. Semiquantitative severity scoring of germ cell degeneration and quantitative analysis of spermatogenic cells for spermatic index (SI) and Sertoli cell index (SEI) was performed. The score of white streak on cut surface area of the testes increased with age, being higher (p < 0.05) in senile dogs than other age groups; no difference was found between adult and old dogs. The proportion of testicular interstitial fibrosis was highest (p < 0.05) in senile dogs. Positive correlations between age and white streak area (rho = 0.77, p < 0.01) as well as age and interstitial fibrosis (rho = 0.63, p < 0.01) were observed. The severity of germ cell degeneration gradually increased with age and differed among age groups (p < 0.05). Age positively correlated with atrophy of seminiferous tubules (rho = 0.93, p < 0.01). The SI was lower (p < 0.05) in senile dogs compared to other age groups, and SI was not different among young, adult and old dogs. Conversely, SEI was significantly higher in senile dogs compared to young, adult and old dogs. A negative correlation between age and SI (rho = −0.69) and a positive correlation between age and SEI (rho = 0.68) were significant (p < 0.01). In conclusion, influence of age on testicular interstitial fibrosis and germ cell degeneration/depletion were pronounced in dogs over 9 years old.
Manipulation of the oestrous cycle of the bitch—what works… for now
Authors: Maenhoudt Cindy , Santos Natalia R. , Fontbonne Alain 
Published: November 2018

ContentsManipulation of the oestrous cycle of the bitch is a common request of pet owners for different reasons. On one side, clients may be interested in temporally preventing oestrus until the bitch has finished the performance career, or to manage the kennel in the presence of a stud dog and to avoid undesirable breeding. Additionally, clients with no interest to use their animal for breeding, may, for ethical reasons, prefer to avoid elective surgery such as ovariectomy, to control reproduction. On the other side, clients may want to induce oestrus to better control the time of birth, to use a male with limited availability during a specific time, or to reduce the duration of the interoestrous interval in bitches with a long oestrous cycle (>8 months). Both these options for oestrous manipulation are based on hormonal treatments. For oestrous prevention, synthetic progesterone has been used since the 1960s. Induction of oestrus has been established with reliable results using dopamine agonists in the late 1980s and more recently using GnRHagonists. This review is focusing on the current and recently available treatments to manipulate the oestrous cycle in the bitch.
Treating hepatitis C virus in dialysis patients: How, when, and why?
Authors: Pagan Javier , Ladino Marco , Roth David 
Published: November 2018

AbstractThe identification of hepatitis C virus (HCV) occurred in 1989, and soon thereafter, it was recognized that there was a higher prevalence of anti‐HCV seropositivity in patients with end‐stage renal disease (ESRD) when compared to the general population. Multiple extrahepatic manifestations have been associated with HCV infection in patients with ESRD; these include an increased prevalence and risk of cardiovascular complications, insulin resistance, diabetes mellitus, and lymphoproliferative disorders. Infection with HCV has also been associated with an increased relative risk of mortality in the ESRD patient when contrasted to those patients without infection. The availability of second‐generation direct‐acting antiviral agents has revolutionized the treatment of HCV in both the general population as well as those patients with advanced chronic kidney disease and receiving dialysis. These new treatment protocols are very well tolerated with limited side effects and manageable drug‐drug interactions while achieving remarkable sustained viral response rates. It is important that nephrologists become familiar with the differing strategies available for HCV‐infected ESRD patients so that the appropriate decision of when and who to treat can be made for each patient.
Measuring Away the Importance of Institutions: The Case of Seigneurial Tenure and Agricultural Output in Canada East, 1851*
Authors: Geloso Vincent 
Published: November 2018

AbstractThis article argues that the 1851 census of Canada East (the modern‐day province of Quebec) requires a set of important corrections. Using corrections based on ethnic origin composition, I demonstrate how significantly wheat and oat yields were underestimated in Canada East. More importantly, I argue that the measurement errors are not randomly distributed and that they are biased against attempts to test the role of institutions. I show how the new method of correcting the data change our interpretation of agricultural efficiency in Lower Canada in the mid‐19th century. While this correction may seem minor, it shows that in the past, the data took a form that was biased against numerous hypotheses concerning land tenure institutions.
Risky Business: Institutional Logics and Risk Taking at Large U.S. Commercial Banks*
Authors: LaBriola Joe 
Published: November 2018

ObjectiveThis article aims to answer whether increased securitization and/or increased shareholder value pressures at commercial banks have led to higher levels of risk.MethodsUsing data on large U.S. commercial banks from several sources, I estimate linear partial‐adjustment models to predict the effects of securitization, as well as CEO incentives to increase shareholder value, on leverage.ResultsThese models provide evidence that increases in the relative size of trading securities at a commercial bank are significantly associated with increases in leverage. Meanwhile, the relative size of total securities and CEO incentives to increase shareholder value do not appear to affect leverage.ConclusionThese findings suggest that limiting commercial bank speculation in securities markets may reduce the likelihood that commercial banks face large losses or become insolvent in financial downturns.
How to…analyse qualitative data in different ways
Authors: Bennett Dierdre , Barrett Aileen , Helmich Esther 
Published: November 2018

SummaryIn this paper, the fifth in a series on qualitative research in medical education, we discuss approaches to analysing qualitative data. We focus primarily on analysing transcribed interview and focus group data. We also touch on the analysis of visual data, a potentially fruitful alternative approach.
Qualitative topological relations between interval type‐2 fuzzy spatial objects
Authors: Guo Jifa , Shao Xiaodong , Mo Xunqiang 
Published: November 2018

AbstractThe topological relations between fuzzy objects are crucial in geographical spatial analysis. A qualitative topological relationship analysis method for interval type‐2 fuzzy spatial objects (IT2 FSOs) is proposed in this article. Similarities between the interval type‐2 fuzzy topological relation matrices and the corresponding crisp topological relation matrices are calculated using Jaccard's similarity measure and sorted to identify the two major relations. Next, the proximity degrees and quantifiers that correspond to these two major relations can be determined. Thus, two methods can be used to describe the relation between two IT2 FSOs; the method proposed in this article conforms to human cognitive habits and meets the requirements of a variety of applications in geographical information systems (GIS). Users can select different boundary definitions, intersection matrix types, and calculation functions for each cell in the intersection matrix, as well as different description methods according to the requirements of different GIS applications.
Investigating Electrostatic Flow Charging Using a Small Scale Test Bench
Authors: Weishaar Philipp C. , Görres Alexander , Murrenhoff Hubertus , Schmitz Katharina 
Published: November 2018

Common examples for electrostatic discharges can be encountered in everyday life. When approaching a grounded surface after walking on insulating flooring material or while riding an escalator one might experience an electrostatic discharge first hand. These discharges generally do not pose a problem but when translated to various fields of engineering, such as in hydraulics, discharges can be the root cause for system failures. The pioneering fields of engineering for electrostatic charging in systems are petro-chemistry and electrical engineering. Researchers in both fields attempted to formulate models to calculate the electrostatic charging a priori. These models provide some indication regarding the magnitude of charge but are currently not suited for the application in hydraulic systems. This is due to the lack of necessary fluid and material parameters for the application of either one of the models. [1, 2]
Previous work in the pioneering fields focused on fluids and materials typical for their respective applications. This paper seeks to take the first step to remedy this situation by developing and commissioning a test bench for investigating a wide variety of hydraulic fluid-material combinations. The fluids pending investigation range from a typical hydraulic fluid based on a group I base oil to a pure polyalphaolefine of group IV. Common materials for hydraulic systems are investigated with a small scale test bench as well, such as steel and brass common to hydraulic applications as well as plastics and rubbers. In order to conduct these investigations a Searle viscometer is presented in this paper. In a Searle viscometer the cylinder is rotating while the cup or pipe remains stationary.
Initially this paper gives the necessity for a small scale test bench using experimental results of an existing large scale test rig. Subsequently, the design of a small scale test bench, the Searle viscometer, will be presented along with a method for measuring the charge density. The small scale test bench is based on the work of Washabaugh and is able to generate the necessary information required for using the chemical reaction-based model [3, 4]. The main feature of the chemical reaction based model is the consideration for different material and fluid influences, beyond the scope of viscosity and system geometry.
Symmetric Single Rod Cylinders With Variable Piston Area? A Comprehensive Approach to the Right Solution
Authors: Kolks Giacomo , Weber Jürgen 
Published: November 2018

In contrast to rotational hydraulic displacement units, such as pumps or motors, conventional hydraulic cylinder actuators do not allow a continuous variation of their displacement quantity: the piston area is regarded constant. In order to adapt to varying load and velocity requirements in a load cycle under torque restrictions of the driving motor, cylinder drives often implement pumps with variable displacement.
In this paper, cylinders with discretely variable effective piston area by means of variable circuitry of multi-chamber cylinders are discussed. Hydraulic symmetry or constant asymmetry of the hydraulic cylinder are traits of the cylinder that are required to fit the cylinder to pump structures for closed-circuit displacement control, as given in electro-hydrostatic compact drives (ECD). A methodology to generate all possible solutions of variable area cylinders under the constraint of ECD requirements is proposed.
A comprehensive description of the solution space is given, based on combinatorics and solution of equation systems. The methodology dealing with abstract cylinder areas is backed up by a general approach to describe the mechanical cylinder design space to combine multiple cylinder areas in one structural unit. Examples for design of three and four area cylinders are given and results are discussed. The paper concludes with the development of a demonstrator design to allow experimental validation in a subsequent step.
Determination of the Dynamic Characteristics of a Hydraulic Reservoir for its Air Release Efficiency Using Multiphase CFD Model
Authors: Mostafavi Rahelehsadat , Tiffin Dominic , Schmitz Katharina 
Published: November 2018

Undissolved air in oil causes various problems for hydraulic systems and strongly decreases the efficiency of the system. In this respect, the hydraulic reservoir as the only component that performs the function of releasing the accumulated air from the system is relevant. In recent years, the air release efficiency in hydraulic reservoirs has been studied both experimentally and in simulation. However, in none of the according studies dynamically changing flow conditions have been considered.
In this paper, the air release behaviour of a hydraulic reservoir is investigated through simulation, considering the dynamics of the system. The developed multiphase CFD model utilizes the open-source CFD tool, OpenFOAM®, based on a Lagrangian Particle Tracking (LPT) within an Eulerian phase. The simulations have been conducted varying the key variables such as oil flow rate and air load at the inlet of the reservoir and yield the air content at the outlet.
A Survey of Industrial Internet of Things in the Field of Fluid Power: Basic Concept and Requirements for Plug-and-Produce
Authors: Alt Raphael , Malzahn Justus , Murrenhoff Hubertus , Schmitz Katharina 
Published: November 2018

Driving aspects in the developments of the Industrial Internet of Things (IIoT) are based on markets demanding a highly flexible production on the one hand and, on the other hand, by the production industry looking for new business models. This is enabled by interconnecting intelligent devices and aggregating and analyzing huge amounts of data. In the section of field devices, targeted new developments are dealing with intelligent systems which support users in each stage of the product life cycle. During installation and commissioning of a new machine, the concept of Plug-and-Produce has been created in the production industry. It is relating to the analogy of Plug-and-Play in the field of information technology which makes it possible to recognize and use devices without additional effort across several platforms. Industrial production systems differ in some aspects from Plug-and-Play computer devices that these methods are not applicable without adjustments and more advanced considerations.
Solutions to support the commissioning process are scope of this contribution and analyzed theoretically by the example of the integration of an electro-hydraulic actuator.
Two results are highlighted in this contribution. Different IIoT related concepts and technologies (i.e. OPC-UA, Cyber-physical systems, semantics) are presented and merged to realize Plug-and-Produce as an holistic business process. Furthermore, the draft combines the domain of fluid power with the abstract and generalized concepts and models and gives an understanding of future requirements for fluid power field devices in the context of IIoT.
Modelling of the Lateral Lubricating Interfaces in External Gear Machines Considering the Effects of Cavitation
Authors: Thiagarajan Divya , Vacca Andrea 
Published: November 2018

This work presents an approach for evaluating the cavitating conditions encountered in the lateral lubricating interfaces which exist between floating lateral bushings and gears in external gear machines (EGMs). Previous work in the authors’ research team had resulted in the development of a full fluid-structure-interaction (FSI)-EHD lubricating model for the lateral lubricating gaps, which was also validated against experiments. However, such a model uses a very simplified and approximate approach to consider aeration or cavitating conditions in the lubricating gap, where the pressures are simply saturated to a constant minimum value during their solution whenever they cross a minimum threshold. This subsequently results in numerically unstable predictions of pressure when substantial cavitating regions are encountered while also violating mass conservation laws.
To overcome these issues, this paper presents a stable mass conserving cavitation algorithm by implementing the universal Reynolds equation in the existing FSI-EHD model which is applicable for both full film and cavitating conditions and has been found to be applicable in several other tribological interfaces. Such a method offers to predict the onset and shape of the cavitating regions without the need for considering complex bubble dynamics. After outlining the formulation and implementation of the new cavitation algorithm, this paper also presents simulations of a commercially available EGM, where using this cavitation algorithm was found to predict realistic pressure distributions in the lubricating interface while also maintaining the stability of such a complex lubricating gap model for EGMs.
Synthetic Esters and Dynamics of Pressure Compensated Proportional Directional Control Valves
Authors: Jakobsen J. H. , Hansen M. R. 
Published: November 2018

The purpose of this paper is to help reduce the uncertainty in behavior introduced when changing hydraulic oil from mineral oil (HLP) to biodegradable oil (synthetic esters - HEES) by comparing the behavior of proportional valves with HLP and with HEES at various temperatures.
The focus of this article is on classic proportional valves used in the industry. The study is based on tests and modelling with characterization of dynamic behavior in mind. The characterization is based on tests of two pressure compensated proportional valves, one with closed loop control of the spool position, and one without. The two ester types tested are one based on a saturated, fully synthetic ester and a regular fully synthetic ester.
The tests consist of steps and frequency responses. Both valves are tested at oil temperatures 20°C, 40°C and 60°C.
The adopted models are based on a third order linear model with parameters identified using frequency responses from actual valve tests.
The variation of amplitude and bias has some influence on the resulting frequency response especially at lower temperatures. But the general tendencies are unaffected by amplitude and bias.
As expected a clear tendency for both valves of increasing dampening at decreasing temperatures is seen regardless of oil type, but the increase in dampening is similar for all oil types.
The saturated ester leads to less bandwidth at lower temperatures for both valves, but the overall variations between all oil types stay within 1.66Hz of each other when tested with the same test parameters.
The investigation indicates that the difference in dynamic characteristics at 20°C caused by the different oil types can not be explained with variations in any single one of the classic liquid properties density and viscosity and more investigations are needed to identify the cause.
Brittle Fracture Prediction Using Code_Aster: Review of Available Models and Focus on the GP Energy Approach
Authors: Jules Samuel , Métais Thomas , Lorentz Eric , Géniaut Samuel 
Published: November 2018

With the life extension of NPPs world-wide, new challenges have emerged in engineering calculations. These challenges often stem from the difficulty to demonstrate an adequate margin for some key components, which have gradually been ageing during the operation of the plant. In particular, the Reactor Pressure Vessel (RPV) is impacted by the irradiation, and the risk of brittle fracture under severe cold shocks must be assessed.
Over the past decades, the RSE-M code [1], which is used in France and internationally for in-service inspection, has been developing methods using a conventional approach to brittle fracture. Analyses are typically performed either using tabulated indices to evaluate analytically the stress intensity factor, or using more advanced approaches which require more complex and time-consuming FEA calculations. Recently, the ongoing trend has been to rely on the latter to demonstrate an adequate margin on the RPV for potential operation beyond 40 years: the question today is whether these existing methods will still provide adequate margins after 50 or 60 years of operation.
In parallel to the conventional approach, a significant amount work has been performed over the past 20 years in France to adapt the historic Griffith energy release-rate approach [2] to engineering space. The work was initiated by Francfort and Marigo [3] who set up a new elastic fracture theory, extended from the Griffith approach.
Within EDF R&D, Lorentz et al. [4] and Wadier et al. [5] have then relied on some of their ideas and applied them to the easier case of the propagation onset of a preexisting crack along a given crack path. Several ingredients are involved in this reduced formulation: the application of an energy minimization principle, the definition of a specific damage model and the use of a notch to represent the crack.
Among other advantages, the Gp method has been developed as a true engineering approach, i.e. not relying on difficult and time-consuming models to set up. It is hence easy to implement in a FE software as a postprocessing of a mechanical calculation. The method has also been applied to various test cases and has shown the potential to increase margins. The drawbacks are that the method is likely restricted to 2D cases for practical reasons.
The paper also provides an overview of the methods implemented in the EDF open source tool code_aster with a specific focus on the Gp approach.
Fast Reactor Cores: Seismic Excitation in the Vertical Direction — Numerical Methods
Authors: Broc Daniel , Artini Gianluca , Cardolaccia Jérome , Martin Laurent 
Published: November 2018

In the frame of the GEN IV Forum and of the ASTRID Project, a program is in progress in the CEA (France) for the development and the validation of numerical tools for the simulation of the dynamic mechanical behavior of the Fast Reactor cores, with both experimental and numerical parts.
The cores are constituted of Fuel Assemblies (or FA) and Neutronic Shields (or NS) immersed in the primary coolant (sodium), which circulates inside the Fuel Assemblies. The FA and the NS are slender structures, inserted in a grid plate, which may be considered as beams form a mechanical point of view. The dynamic behavior of this system has to be understood, for design and safety studies.
This dynamic behavior of the core is strongly influenced by the sodium and by contacts between the beams at the pads level and at the top. The fluid leads to complex interactions between the structures in the whole core. The contacts between the beams limit the relative displacements.
Two main movements have been considered so far: global horizontal movements under a seismic excitation, and opening of the core.
Physical and numerical methods and tools have been developed to describe and simulate the dynamic behavior. These methods are integrated in CAST3M, general computer code developed at the CEA Saclay. The assemblies are modeled as beams. The impacts at the pads between the assemblies are taken into account by using a nonlinear model. The Fluid Structure Interaction is taken into account by using homogenization methods.
This paper is devoted to the improvement of these methods to take into account the vertical component of a seismic excitation. The key points are:
- the fluid structure coupling in the vertical direction,
- the modification of the description of the impacts to take into account the vertical displacements of the assemblies,
- the modification of the boundary condition at the foot of the assembly, in order to take into account the uplift with a nonlinear model.