bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of the density of extruded pellets on starch digestion kinetics, rumen fermentation, fiber digestibility and enteric methane production in dairy cows
Authors: Khan Ghulam Q. , Prestløkken Egil , Lund Peter , Hellwing Anne L. F. , Larsen Mogens 
Published: November 2022

AbstractDynamics of starch digestion in dairy cows fed extruded pellets differing in physical functional properties were investigated by measuring starch digestibility, post‐prandial rumen fermentation patterns, and post‐prandial duodenal starch appearance. Additionally, starch digestion effects on neutral detergent fiber (NDF) digestibility and methane (CH4) emission were studied. Pure barley was extruded to produce three treatments having pellets of either low‐density (LD), medium‐density (MD) or high‐density (HD). The experiment was conducted in a 3 × 3 Latin square design using three lactating Danish Holstein cows fitted with ruminal, duodenal and ileal cannulas. After the allocation of experimental concentrate directly into the rumen through the rumen cannula, cows were fed a basal diet low in starch. Eight samples were collected on equal time intervals (9 h) from duodenal digesta, ileal digesta and feces (grab sample) to determine digestibility. For post‐prandial rumen fermentation patterns, four sample sets of rumen dorsal, medial and ventral fluid were taken from each cow, whereas for post‐prandial duodenal starch appearance, 14 samples of duodenal chyme were obtained from each cow relative to morning feeding of experimental concentrate at 07:00 h. Ruminal, small intestinal, hindgut and total tract digestibility of starch did not differ among treatments. Similarly, NDF digestibility and CH4 emission also remained unaffected by treatments. However, compared with the LD and MD treatments, the HD treatment showed higher acetate: propionate ratio at all positions in the rumen and a higher post‐prandial duodenal starch appearance. This indicates lower ruminal starch degradation (RSD) and higher starch flow into the small intestine for HD treatment. In conclusion, the current study indicates that pellets' physical properties can manipulate RSD, where pellets with high density and fluid stability can partly shift starch digestion from the rumen to the small intestine. Indeed, further investigations are needed.
Hyperammonaemia disrupts daily rhythms reversibly by elevating glutamate in the central circadian pacemaker
Authors: Granados‐Fuentes Daniel , Cho Kevin , Patti Gary J. , Costa Rodolfo , Herzog Erik D. , Montagnese Sara 
Published: November 2022

AbstractPatients with cirrhosis exhibit features of circadian disruption. Hyperammonaemia has been suggested to impair both homeostatic and circadian sleep regulation. Here, we tested if hyperammonaemia directly disrupts circadian rhythm generation in the central pacemaker, the suprachiasmatic nuclei (SCN) of the hypothalamus. Wheel‐running activity was recorded from mice fed with a hyperammonaemic or normal diet for ~35 days in a 12:12 light–dark (LD) cycle followed by ~15 days in constant darkness (DD). The expression of the clock protein PERIOD2 (PER2) was recorded from SCN explants before, during and after ammonia exposure, ±glutamate receptor antagonists. In LD, hyperammonaemic mice advanced their daily activity onset time by ~1 h (16.8 ± 0.3 vs. 18.1 ± 0.04 h, p = .009) and decreased their total activity, concentrating it during the first half of the night. In DD, hyperammonaemia reduced the amplitude of daily activity (551.5 ± 27.7 vs. 724.9 ± 59 counts, p = .007), with no changes in circadian period. Ammonia (≥0.01 mM) rapidly and significantly reduced PER2 amplitude, and slightly increased circadian period. The decrease in PER2 amplitude correlated with decreased synchrony among circadian cells in the SCN and increased extracellular glutamate, which was rescued by AMPA glutamate receptor antagonists. These data suggest that hyperammonaemia affects circadian regulation of rest‐activity behaviour by increasing extracellular glutamate in the SCN.
The impact of xylem geometry on olive cultivar resistance to Xylella fastidiosa: An image‐based study
Authors: Walker Nancy C. , White Steven M. , McKay Fletcher Dan , Ruiz Siul A. , Rankin Kathryn E. , De Stradis Angelo , Saponari Maria , Williams Katherine A. , Petroselli Chiara , Roose Tiina 
Published: November 2022

AbstractXylella fastidiosa is a xylem‐limited plant pathogen infecting many crops globally and is the cause of the recent olive disease epidemic in Italy. One strategy proposed to mitigate losses is to replant susceptible crops with resistant varieties. Several genetic, biochemical and biophysical traits are associated to X. fastidiosa disease resistance. However, mechanisms underpinning resistance are poorly understood. We hypothesize that the susceptibility of olive cultivars to infection will correlate to xylem vessel diameters, with narrower vessels being resistant to air embolisms and having slower flow rates limiting pathogen spread. To test this, we scanned stems from four olive cultivars of varying susceptibility to X. fastidiosa using X‐ray computed tomography. Scans were processed by a bespoke methodology that segmented vessels, facilitating diameter measurements. Though significant differences were not found comparing stem‐average vessel section diameters among cultivars, they were found when comparing diameter distributions. Moreover, the measurements indicated that although vessel diameter distributions may play a role regarding the resistance of Leccino, it is unlikely they do for FS17. Considering Young–Laplace and Hagen–Poiseuille equations, we inferred differences in embolism susceptibility and hydraulic conductivity of the vasculature. Our results suggest susceptible cultivars, having a greater proportion of larger vessels, are more vulnerable to air embolisms. In addition, results suggest that under certain pressure conditions, functional vasculature in susceptible cultivars could be subject to greater stresses than in resistant cultivars. These results support investigation into xylem morphological screening to help inform olive replanting. Furthermore, our framework could test the relevance of xylem geometry to disease resistance in other crops.
Utilizing deep learning for dermal matrix quality assessment on in vivo line‐field confocal optical coherence tomography images
Authors: Breugnot Josselin , Rouaud‐Tinguely Pauline , Gilardeau Sophie , Rondeau Delphine , Bordes Sylvie , Aymard Elodie , Closs Brigitte 
Published: November 2022

AbstractBackgroundLine‐field confocal optical coherence tomography (LC‐OCT) is an imaging technique providing non‐invasive “optical biopsies” with an isotropic spatial resolution of ∼1  μm and deep penetration until the dermis. Analysis of obtained images is classically performed by experts, thus requiring long and fastidious training and giving operator‐dependent results. In this study, the objective was to develop a new automated method to score the quality of the dermal matrix precisely, quickly, and directly from in vivo LC‐OCT images. Once validated, this new automated method was applied to assess photo‐aging‐related changes in the quality of the dermal matrix.Materials and methodsLC‐OCT measurements were conducted on the face of 57 healthy Caucasian volunteers. The quality of the dermal matrix was scored by experts trained to evaluate the fibers’ state according to four grades. In parallel, these images were used to develop the deep learning model by adapting a MobileNetv3‐Small architecture. Once validated, this model was applied to the study of dermal matrix changes on a panel of 36 healthy Caucasian females, divided into three groups according to their age and photo‐exposition.ResultsThe deep learning model was trained and tested on a set of 15 993 images. Calculated on the test data set, the accuracy score was 0.83. As expected, when applied to different volunteer groups, the model shows greater and deeper alteration of the dermal matrix for old and photoexposed subjects.ConclusionsIn conclusion, we have developed a new method that automatically scores the quality of the dermal matrix on in vivo LC‐OCT images. This accurate model could be used for further investigations, both in the dermatological and cosmetic fields.
Blood shifts between body compartments during submaximal exercise with induced expiratory flow limitation in healthy humans
Authors: Stucky Frédéric , Uva Barbara , Kayser Bengt , Aliverti Andrea 
Published: November 2022

AbstractExternal expiratory flow limitation (EFLe) can be applied in healthy subjects to mimic the effects of chronic obstructive pulmonary disease during exercise. At maximal exercise intensity, EFLe leads to exercise intolerance owing to respiratory pump dysfunction limiting venous return. We quantified blood shifts between body compartments to determine whether such effects can be observed during submaximal exercise, when the load on the respiratory system is milder. Ten healthy men (25.2 ± 3.2 years of age, 177.3 ± 5.4 cm in height and weighing 67.4 ± 5.8 kg) exercised at 100 W (∼40% of maximal oxygen uptake) while breathing spontaneously (CTRL) or with EFLe. We measured respiratory dynamics with optoelectronic plethysmography, oesophageal (Pes) and gastric (Pga) pressures with balloon catheters, and blood shifting between body compartments with double body plethysmography. During exercise, EFLe resulted in the following changes: (i) greater intrabreath blood shifts between the trunk and the extremities [518 ± 221 (EFLe) vs. 224 ± 60 ml (CTRL); P < 0.001] associated with lower Pes during inspiration (r = 0.53, P < 0.001) and higher Pga during expiration (r = 0.29, P < 0.024); and (ii) a progressive pooling of blood in the trunk over time (∼700 ml after 3 min of exercise; P < 0.05), explained by a predominant effect of lower inspiratory Pes (r = 0.54, P < 0.001) over that of increased Pga. It follows that during submaximal exercise, EFLe amplifies the respiratory pump mechanism, with a prevailing contribution from lower inspiratory Pes over increased expiratory Pga, drawing blood into the trunk. Whether these results can be replicated in chronic obstructive pulmonary disease patients remains to be determined.
imageKey points
External expiratory flow limitation (EFLe) can be applied in healthy subjects to mimic the effects of chronic obstructive pulmonary disease and safely study the mechanisms of exercise intolerance associated with the disease.
At maximal exercise intensity with EFLe, exercise intolerance results from high expiratory pressures altering the respiratory pump mechanism and limiting venous return.
We used double body plethysmography to quantify blood shifting between the trunk and the extremities and to examine whether the same effects occur with EFLe at submaximal exercise intensity, where the increase in expiratory pressures is milder.
Our data show that during submaximal exercise, EFLe amplifies the respiratory pump mechanism, each breath producing greater blood displacements between the trunk and the extremities, with a prevailing effect from lower inspiratory intrathoracic pressure progressively drawing blood into the trunk.
These results help us to understand the haemodynamic effects of respiratory pressures during submaximal exercise with expiratory flow restriction.
Numerical Study of Radiation and Fuel–Air Unmixedness on the Performance of a Dry Low NOx Combustor
Authors: Wiranegara Raditya Yudha , Igie Uyioghosa , Ghali Pierre , Zhao Rang , Abbott David , Hamilton Richard 
Published: November 2022

Abstract
The development of gas turbine combustors is expected to consider the effects of radiation heat transfer in modeling. However, this is not always the case in many studies that neglect this for adiabatic conditions. The effect of radiation is substantiated here, concerning the impact on the performance, mainly the emissions. Also, the fuel–air unmixedness (mixing quality) influenced by the combustor design and operational settings has been investigated with regard to the emissions. The work was conducted with a Mitsubishi-type dry low NOx combustor developed and validated against experimental data. This 3D computational fluid dynamics study was implemented using Reynolds-averaged Navier Stokes simulation and the radiative transfer equation model. It shows that NO, CO, and combustor outlet temperature reduce when the radiative effect is considered. The reductions are 17.6% and below 1% for the others, respectively. Thus, indicating a significant effect on NO. For unmixedness across the combustor in a non-reacting simulation, the mixing quality shows a direct relationship with the turbulence kinetic energy (TKE) in the reacting case. The most significant improvements in unmixedness are shown around the main burner. Also, the baseload shows better mixing, higher TKE, and lower emissions (particularly NO) at the combustor outlet, compared to part-load.
Synthesis of Recursive Control Barrier Functions
Authors: de Castro Ricardo , Feng Shuang 
Published: November 2022

Abstract
This paper deals with the enforcement of safety constraints using control barrier functions (CBFs). We focus on dynamic systems that have high relative degree and where the output needs to be differentiated multiple times to obtain an explicit dependence on the control input. As the system approaches operating points that are close to the safety boundary, the CBF shrinks the allowed control action space. To quantify this shrinkage, we propose practical proxy metrics to capture the volume of the CBFs action space. We exploit these proxy metrics to derive sum-of-squares optimization formulations that synthesize CBFs with high-order degree, in particular their extended class K functions. We apply this tuning technique to synthesize CBFs that avoid vehicle collisions in an adaptive cruise control problem. Simulation results demonstrate the ability of our tuning approach to reduce loss of control performance when the system operates close to the safety boundary.
Research on the Mechanism of Cathode Failure of Lead-Acid Battery Under Extreme Conditions
Authors: Li Yaowei , Lyu Nawei , Jin Yang 
Published: November 2022

Abstract
Lead-acid batteries have the advantages of wide temperature adaptability, large discharge power, and high safety factor. It is still widely used in electrochemical energy storage systems. In order to ensure the application of batteries under extreme working conditions, it is necessary to explore the degradation mechanism. In this study, the experimental battery is the same type of 2 V-500 Ah lead-acid battery produced by different manufacturers. First, the three batteries were subjected to the same high temperature and high current cycle thermal shock test (50 °C, 0.2 C current) combined with quantitative analysis of plate active material and microscopic morphology observation. In addition, numerical studies are used to simulate the distribution of electrical parameters on the positive plate and grid. The above three parts are combined to study the causes of accelerated battery decay under high temperature and high current conditions. The results showed that the extreme conditions aggravated the non-uniformity of the potential distribution of the positive plate and the grid, which increased by 10.62% and 51.59%, respectively. The battery with higher remaining capacity has more α-PbO2 in the active material, and has a considerable amount of β-PbO2. The battery with the smallest remaining capacity has the largest volume of active material. The volume of the material affects the electrochemical reaction surface area. The larger the volume of the material, the higher the resistance of that part, which will lead to an increase in the overall impedance of the battery.
Influence Mechanism of Trimming Impeller Diameter in a Centrifugal Pump by Computational Fluid Dynamics Investigation
Authors: Han Yong , Li Hui , Tiganik Taavi , Wang Yuqiang , Zhou Ling 
Published: November 2022

Abstract
Trimming the impeller diameter of a centrifugal pump is the easiest and most economical way to adjust its efficient operating range based on its original performance. Three impellers obtained by trimming the diameter are investigated. Energy performance, internal flow field, and entropy production analysis have been discussed in different cases. The results show that trimming the impeller diameter causes a great change in the energy performance of centrifugal pumps. The turbulent kinetic energy (TKE) distribution and entropy production also change significantly. The best efficiency point (BEP) shifts to low flowrate with trimming impeller diameter. The BEP shift rate was 6.67% and 20% for trimming amounts of 5.15% and 10.29%, respectively. As the impeller diameter decreases, the backflow phenomenon that occurs at the diffuser inlet at low flowrate improves. The ratio of mechanical energy to kinetic energy and pressure energy is not constant for pumps with different impeller diameters. The energy performance changes are mainly caused by flow changes inside the impeller, chamber, and diffuser. The results could be referred to as the design and selection of centrifugal pumps.
Effect of Wrapping Force on the Effective Elastic Behavior of Packed Cylinders
Authors: Yin Huiming , Cui Junhe , Teka Linda G. , Zadshir Mehdi 
Published: November 2022

Abstract
When cylinders are packed and wrapped by the bands around the surface, the effective elastic behavior in the cross section of the assembly, which is of significance to its stability and integrity, can be controlled by the wrapping force in the band. The wrapping force is transferred to the cylinders through the Hertz contact between each pair of neighboring cylinders, which is validated by the experiments. The Singum model is introduced to study the mechanical behaviors of the packed cylinders with two-dimensional (2D) packing lattices, in which an inner cylinder is simulated by a continuum particle of Singum and the inter-cylinder force is governed by the Hertz contact model so as to derive the effective stress-strain relationship. The wrapping force will produce configurational forces given a displacement variation, which significantly changes the effective stiffness of the packed cylinders. The hexagonal packing exhibits isotropic elasticity whereas the square packing is anisotropic. The efficacy of our model is demonstrated by comparing the closed form elasticity against the numerical simulation and the previous models. The explicit form of elasticity can be used for packing design and quality control of cable construction and installation.
Onset of Flow Separation Phenomenon in a Low-Specific Speed Centrifugal Pump Impeller
Authors: Liu Xiao-Dong , Farhat Mohamed , Li Yao-Jun , Liu Zhu-Qing , Yang Wei 
Published: November 2022

AbstractThe efficiency of centrifugal pumps drops sharply when the flowrate is reduced below a threshold value. This is due to a profound change in the flow structure, characterized by a large of portion flow separation near the impeller blades and the formation of energy-intensive recirculation zones. So far, it is not clear how such flow separation may initiate and develop. This study combines state-of-the-art experiments and numerical simulations to explore the onset of flow separation in centrifugal impellers. In particular, a high-frequency particle image velocimetry (PIV) system is used to visualize the velocity field in impeller channels. The continuous relative velocity value and deviation angle relative to the blade surface are displayed before the stall inception conditions. Meanwhile, the validated numerical simulation method is used to compute the flow at similar experimental conditions. The results clearly show a cylindrical vortex band exists near the impeller shroud. As the flowrate decreases, the vortex grows gradually stronger, while moving to the junction between the impeller shroud and blade suction side, and then toward impeller hub along the blade suction side. This growing and moving vortex is the main cause of the flow separation near blade suction side observed in our experiments. Interestingly, the impeller head remains insensitive to this vortex until it causes the flowrate in the adjacent impeller channels to be redistributed. This led us to believe that stalled flow can be detected before it affects the hydrodynamic performances.
Metric-Based Meta-Learning for Cross-Domain Few-Shot Identification of Welding Defect
Authors: Xie Tingli , Huang Xufeng , Choi Seung-Kyum 
Published: November 2022

Abstract
With the development of deep learning and information technologies, intelligent welding systems have been further developed, which achieve satisfactory identification of defective welds. However, the lack of labeled samples and complex working conditions can hinder the improvement of identification models. This paper explores a novel method based on metric-based meta-learning for the classification of welding defects with cross-domain few-shot (CDFS) problems. First, an embedding module using convolutional neural network (CNN) is applied to perform feature extraction and generate prototypes. The embedding module only contains one input layer, multiple convolutions, max-pooling operators, and batch normalization layers, which has the advantages of low computational cost and high generalization of images. Then the prototypical module using a prototypical network (PN) is proposed to reduce the influence of domain-shift caused by different materials or measurements using the representations in embedding space, which can improve the performance of few-shot welding defects identification. The proposed approach is verified on real welding defects under different welding conditions from the Camera-Welds dataset. For the K-shot classification on different tasks, the proposed method achieves the highest average testing accuracy compared to the existing methods. The results show the proposed method outperforms the model-based meta-learning (MAML) and transfer-learning method.
Systematic Generation of 5-Axis Manufacturing Machines
Authors: Jetton Cole , Rudd Liam , Campbell Matthew I. 
Published: November 2022

Abstract
Additive and subtractive machines that exhibit five and six degrees of freedom are on the cutting edge of manufacturing technology. The workspace for these machines can be determined by the joint types and orientations chosen during the design process. Thus, many joint configurations should be considered during the design. This paper presents a method for exhaustively generating and evaluating serial mechanisms using computer algebra systems and investigates four machines as case studies. The position and angle of the end point of the mechanism was computed as a function of joint actuation allowing a configuration to be evaluated in a variety of metrics including volume, tool angle range, and singularities (where the machine loses a degree of freedom). The exhaustive search generated and tested joint configurations to determine which had five axis control within their workspace. The case studies looked at four machines in detail, using both convex hull and alpha shape to calculate the workspace volume, their ability to maintain five axis control, and compared the viability of each configuration. The application of this method led to several different, but viable configurations. One can then narrow down further based on situational requirements of the target environment.