bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hemodynamics in pig‐to‐baboon heterotopic thoracic cardiac xenotransplantation: Recovery from perioperative cardiac xenograft dysfunction and impairment by cardiac overgrowth
Authors: Bender Martin , Panelli Alessandro , Reichart Bruno , Radan Julia , Mokelke Maren , Neumann Elisabeth , Buttgereit Ines , Michel Sebastian , Bauer Andreas , Fresch Ann Kathrin , Mayr Tanja , Werner Fabian , Egerer Stefanie , Bähr Andrea , Kessler Barbara , Klymiuk Nikolai , Ayares David , Wolf Eckhard , Hagl Christian , Brenner Paolo , Längin Matthias , Abicht Jan‐Michael 
Published: January 2024

AbstractIntroductionOrthotopic cardiac xenotransplantation has seen notable improvement, leading to the first compassionate use in 2022. However, it remains challenging to define the clinical application of cardiac xenotransplantation, including the back‐up strategy in case of xenograft failure. In this regard, the heterotopic thoracic technique could be an alternative to the orthotopic procedure. We present hemodynamic data of heterotopic thoracic pig‐to‐baboon transplantation experiments, focusing on perioperative xenograft dysfunction and xenograft overgrowth.MethodsWe used 17 genetically modified piglets as donors for heterotopic thoracic xenogeneic cardiac transplantation into captive‐bred baboons. In all animals, pressure probes were implanted in the graft's left ventricle and the recipient's ascending aorta and hemodynamic data (graft pressure, aortic pressure and recipient's heart rate) were recorded continuously.ResultsAortic pressures and heart rates of the recipients’ hearts were postoperatively stable in all experiments. After reperfusion, three grafts presented with low left ventricular pressure indicating perioperative cardiac dysfunction (PCXD). These animals recovered from PCXD within 48 h under support of the recipient's heart and there was no difference in survival compared to the other 14 ones. After 48 h, graft pressure increased up to 200 mmHg in all 17 animals with two different time‐patterns. This led to a progressive gradient between graft and aortic pressure. With increasing gradient, the grafts stopped contributing to cardiac output. Grafts showed a marked weight increase from implantation to explantation.ConclusionThe heterotopic thoracic cardiac xenotransplantation technique is a possible method to overcome PCXD in early clinical trials and an experimental tool to get a better understanding of PCXD. The peculiar hemodynamic situation of increasing graft pressure but missing graft's output indicates outflow tract obstruction due to cardiac overgrowth. The heterotopic thoracic technique should be successful when using current strategies of immunosuppression, organ preservation and donor pigs with smaller body and organ size.
Refueling the Engine
Authors: Blumreiter Julie 
Published: January 2024

Abstract
Diesel engine fuels cause unsustainable greenhouse gas impacts due to the fossil fuel diesel uses, rather than the engine design. Free the diesel engine from petroleum-derived fuels—or even from fuels that are required to be chemically similar to diesel—so that it can operate on any fuel and it can meet its essential economic functions while greenhouse gas emissions are reduced.
Flow Rate and Wall Shear Stress Characterization of a Biomimetic Aerosol Exposure System
Authors: Emma Sarles S. , Hensel Edward C. , Terry Janessa , Nuss Caleb , Robinson Risa J. 
Published: January 2024

Abstract
Current in vitro emissions and exposure systems lack biomimicry, use unrealistic flow conditions, produce unrealistic dose, and provide inaccurate biomechanical cues to cell cultures, limiting ability to correlate in vitro outcomes with in vivo health effects. A biomimetic in vitro system capable of puffing aerosol and clean air inhalation may empower researchers to investigate complex questions related to lung injury and disease. A biomimetic aerosol exposure system (BAES), including an electronic cigarette adapter, oral cavity module (OCM), and bifurcated exposure chamber (BEC) was designed and manufactured. The fraction of aerosol deposited in transit to a filter pad or lost as volatiles was 0.116±0.021 in a traditional emissions setup versus 0.098 ± 0.015 with the adapter. The observed flowrate was within 5% of programed flowrate for puffing (25 mL/s), puff-associated respiration (450 mL/s), and tidal inhalation (350 mL/s). The maximum flowrate observed in the fabricated BAES was 450 mL/s, exceeding the lower target nominal wall shear stress of 0.025 Pa upstream of the bifurcation and fell below the target of 0.02 Pa downstream. This in vitro system addresses several gaps observed in commercially available systems and may be used to study many inhaled aerosols. The current work illustrates how in silico models may be used to correlate results of an in vitro study to in vivo conditions, rather than attempting to design an in vitro system that performs exactly as the human respiratory tract.
The Presence of Chaos in a Viscoelastic Harmonically Forced Von Mises Truss
Authors: Ghoshal Pritam , Gibert James M. , Bajaj Anil K. 
Published: January 2024

Abstract
This work investigates how viscoelasticity affects the dynamic behavior of a lumped-parameter model of a bistable von Mises truss. The system is controlled by a linear first-order equation and a second-order nonlinear Duffing equation with a quadratic nonlinearity that governs mechanical behavior. The second-order equation controls mechanical oscillations, while the linear first-order equation controls viscoelastic force evolution. Combined, the two equations form a third-order jerk equation that controls system dynamics. Viscoelasticity adds time scales and degrees-of-freedom to material behavior, distinguishing it from viscosity-only systems. Due to harmonic excitation, the system exhibits varied dynamic responses, from periodic to quasi-periodic to chaotic. We explore the dynamics of a harmonically forced von Mises truss with viscous damping to address this purpose. We demonstrate this system's rich dynamic behavior due to driving amplitude changes. This helps explain viscoelastic system behavior. A viscoelastic unit replaces the viscous damper, and we show that, although viscous damping merely changes how fast the trajectory decays to an attractor, viscoelasticity modifies both the energy landscape and the rate of decay. In a conventional linear solid model, three viscoelastic parameters control the system's behavior instead of one, as in pure viscous damping. This adds degrees-of-freedom that affect system dynamics. We present the parameter space for chaotic behavior and the shift from regular to irregular motion. Finally, Melnikov's criteria identify the regular-chaotic threshold. The system's viscous and elastic components affect the chaotic threshold amplitude
Numerical Analysis of Unsteady Phenomena in a Contra-Rotating Stage Based on the Reduction of Local Entropy Production
Authors: Jia Xingyu , Zhang Xi , Yan Qiushuang , Zhao Zicheng 
Published: January 2024

Abstract
The primary purpose of this study is the reduction of local entropy production in a contra-rotating stage. As such, the unsteady flow phenomena and the impact of radial load distribution on these phenomena and local entropy production need to be clarified. In this study, the stress-blended eddy simulation (SBES) turbulence model is utilized to capture the vortices in the flow separation zone, and the γ-Reθ transition model is employed to predict the transition phenomenon within the boundary layer. Entropy production rate models suitable for different turbulence models are constructed separately to calculate local entropy production. Vortex visualization is achieved according to the λci criterion, and the relative vorticity change rate is used to analyze the components of the tip clearance vortices. The transition phenomenon is analyzed from the perspectives of both the Euler and the Lagrange descriptions. The primary findings can be summarized as follows: the transition begins earlier and progresses more rapidly in the rear rotor. Wake propagation, occurring at double the frequency, entropy production rate within the boundary layer changes in synchrony with the wall shear stress at the same frequency. Additionally, an investigation of the tip clearance vortices concludes that the main structure of the tip clearance vortices coincides with the flow pattern of the high entropy production rate region, and the flow structure related to the high divergence area is essential for considering subsequent optimization with the aim of reducing the entropy production rate.
Equilibrium Mechanical Properties of the Nonhuman Primate Cervix
Authors: Fang Shuyang , Shi Lei , Vink Joy-Sarah Y. , Feltovich Helen , Hall Timothy J. , Myers Kristin M. 
Published: January 2024

Abstract
Cervical remodeling is critical for a healthy pregnancy. Premature tissue changes can lead to preterm birth (PTB), and the absence of remodeling can lead to post-term birth, causing significant morbidity. Comprehensive characterization of cervical material properties is necessary to uncover the mechanisms behind abnormal cervical softening. Quantifying cervical material properties during gestation is challenging in humans. Thus, a nonhuman primate (NHP) model is employed for this study. In this study, cervical tissue samples were collected from Rhesus macaques before pregnancy and at three gestational time points. Indentation and tension mechanical tests were conducted, coupled with digital image correlation (DIC), constitutive material modeling, and inverse finite element analysis (IFEA) to characterize the equilibrium material response of the macaque cervix during pregnancy. Results show, as gestation progresses: (1) the cervical fiber network becomes more extensible (nonpregnant versus pregnant locking stretch: 2.03 ± 1.09 versus 2.99 ± 1.39) and less stiff (nonpregnant versus pregnant initial stiffness: 272 ± 252 kPa versus 43 ± 43 kPa); (2) the ground substance compressibility does not change much (nonpregnant versus pregnant bulk modulus: 1.37 ± 0.82 kPa versus 2.81 ± 2.81 kPa); (3) fiber network dispersion increases, moving from aligned to randomly oriented (nonpregnant versus pregnant concentration coefficient: 1.03 ± 0.46 versus 0.50 ± 0.20); and (4) the largest change in fiber stiffness and dispersion happen during the second trimester. These results, for the first time, reveal the remodeling process of a nonhuman primate cervix and its distinct regimes throughout the entire pregnancy.
The Influence of a Booster Seat on the Motion of the Reclined Small Female Anthropomorphic Test Device in Low-Acceleration Far-Side Lateral Oblique Impacts
Authors: Graci Valentina , Burns John , Duong Andrew , Griffith Madeline , Seacrist Thomas 
Published: January 2024

Abstract
Belt-positioning booster (BPB) seats may prevent submarining in reclined child occupants in frontal impacts. BPB-seated child volunteers showed reduced lateral displacement in reclined seating in low-acceleration lateral-oblique impacts. As submarining was particularly evident in reclined small adult female occupants, we examined if a booster seat could provide similar effects on the kinematics of the small female occupant to the ones found on the reclined child volunteers in low-acceleration far-side lateral oblique impacts. The THOR-AV-5F was seated on a vehicle seat on a sled simulating a far-side lateral-oblique impact (80 deg from frontal, maximum acceleration ∼2 g, duration ∼170 ms). Lateral and forward head and trunk displacements, trunk rotation, knee-head distance, seatbelt loads, and head acceleration were recorded. Three seatback angles (25 deg, 45 deg, 60 deg) and two booster conditions were examined. Lateral peak head and trunk displacements decreased in more severe reclined seatback angles (25–36 mm decrease compared to nominal). Forward peak head, trunk displacements, and knee-head distance were greater with the seatback reclined and no BPB. Knee-head distance increased in the severe reclined angle also with the booster seat (&gt;40 mm compared to nominal). Seat belt peak loads increased with increased recline angle with the booster, but not without the booster seat. Booster-like solutions may be beneficial for reclined small female adult occupants to reduce head and trunk displacements in far-side lateral-oblique impacts, and knee-head distance and motion variability in severe reclined seatback angles.
Singularity Analysis of Actuation Coordination and New Indices for Optimal Design of Redundantly Actuated Parallel Manipulators
Authors: Liu Xiaofei , Wan Bo , Liu Yu , Wang Yu , Zhao Yongsheng 
Published: January 2024

Abstract
This paper focuses on the singularity of actuation coordination of redundantly actuated parallel manipulators and proposes a series of novel indices to evaluate the actuation coordination. The singularity is analyzed based on the coordinated dynamics model and divided into two categories: input singularity and output singularity. Influences of the singularity on the control performance of redundantly actuated parallel manipulators are studied with mechanisms 2RPU + 2UPR + RPR and 3RPR. Local and global performance indices of redundantly actuated parallel manipulators with actuation coordination are put forward, and the dimension optimization method considering the proposed indices is studied based on mechanism 6RPS. The research of this article possesses good reference significance for the performance analysis and control application of redundantly actuated parallel manipulators.
Identification of Real and Complex Solution Varieties and Their Singularities Defined by Loop Constraints of Linkages Using the Kinematic Tangent Cone
Authors: Müller Andreas , Li Zijia 
Published: January 2024

Abstract
The configuration space (c-space) of a mechanism is the real-solution variety of a set of loop closure constraints, which is therefore the chief object in kinematic analysis. Singularities of this variety (referred to as c-space singularities) are singular configurations of the mechanism. In addition, a mechanism may exhibit other kinematic singularities that are not visible from the differential geometry of the c-space (referred to as hidden singularities). Such situations were analyzed by investigating the local geometry of the c-space and its corank stratification. It has been shown recently that hidden singularities and shakiness can be attributed to the fact that complex solution branches intersect with the c-space, i.e., with real-solution branches. This paper employs the kinematic tangent cone to identify local solution branches. While the kinematic tangent cone is an established generally applicable concept, which gives rise to a computational (numeric and symbolic) algorithm, it has yet only been applied to analyzing the real-solution set. Application of the method is shown for several examples. Further, the algebraic aspects are briefly elaborated.
Thermal Performance of Double Walls With Polystyrene Bead Insufflation
Authors: Al Fakhoury Joelle , Sassine Emilio , Cherif Yassine , Dgheim Joseph , Antczak Emmanuel , Chartier Thierry 
Published: January 2024

Abstract
The improvement of the thermal and energy efficiency of buildings, regardless of their geographical location, is an objective that needs to be achieved quickly. The objective of this work is to develop a method to evaluate the thermal performance of a hollow block masonry double wall under controlled and pseudo-random experimental conditions. First, the thickness of the air space separating the two walls was varied to see the influence of the gap on this type of wall. Then, this technology was filled with polystyrene beads to improve the thermal performance at the wall scale. Finally, each case studied at wall scale was modeled and simulated numerically in 3D using COMSOL Multiphysics under the same conditions, properties, and dimensions as the one tested experimentally. The conclusions confirm that the double wall filled with polystyrene has excellent thermal behavior compared to the one without the addition of polystyrene beads and that the comparison between numerical and experimental results gave very satisfactory results.
Numerical Investigation on Thermal Performance of Nanofluid-Assisted Wickless Heat Pipes for Electronic Thermal Management
Authors: Jose Jobin , Hotta Tapano Kumar 
Published: January 2024

Abstract
Heat pipes are passive heat transfer systems and serve as an effective thermal management solution for electronic devices. The adaptability of heat pipes makes these suited for a wide application range, especially in the field of electronic thermal management. The current study highlights the transient numerical analysis of wickless heat pipes (thermosyphons) for the thermal management of electronic devices. The thermal performance of the thermosyphon is analyzed using both copper oxide (CuO) and aluminum oxide (Al2O3) nanofluids with their concentrations at 1% and 5%. Deionized (DI) water is employed as a reference case for comparison. The study is carried out for variable heat inputs to the thermosyphon ranging 10–50 W for a time interval of 30 s. The idea is to analyze the effect of the evaporator heat input and the nanoparticles concentration on the temperature, heat transfer coefficient, thermal resistance, and effective thermal conductivity of the heat pipe. The results indicate that CuO nanoparticles at a 5% concentration lead to a maximum thermal resistance reduction of 4.31% at 50 W, while alumina nanoparticles at the same concentration lead to a more substantial reduction of 6.66% at the same heat load. The evaporator temperature varies between 377.52 K to 374.99 K using deionized water, and 376.95 K to 374.29 K using CuO nanofluid (at 1% concentration). The heat pipe's evaporator attains its highest convective heat transfer coefficient (437.91 W/m2K) by using alumina nanofluid with 1% nanoparticle concentration at 50 W. Moreover, the effective thermal conductivity of the heat pipe is enhanced by 5% and 7% for copper oxide and aluminum oxide nanofluids (with 5% concentration), respectively, at 50 W. Thus, the nanofluids play a significant role in improving the efficiency and reliability of electronic components. These findings demonstrate the potential of using the nanofluids in thermosyphons to enhance their thermal performance in electronic cooling applications.
Human metapneumovirus infection of organoid-derived human bronchial epithelium represents cell tropism and cytopathology as observed in
in vivo
models
Authors: Ribó-Molina Pau , van Nieuwkoop Stefan , Mykytyn Anna Z. , van Run Peter , Lamers Mart M. , Haagmans Bart L. , Fouchier Ron A. M. , van den Hoogen Bernadette G. 
Published: January 2024

ABSTRACT

Human metapneumovirus (HMPV), a member of the
Pneumoviridae
family, causes upper and lower respiratory tract infections in humans.
In vitro
studies with HMPV have mostly been performed in monolayers of undifferentiated epithelial cells.
In vivo
studies in cynomolgus macaques and cotton rats have shown that ciliated epithelial cells are the main target of HMPV infection, but these observations cannot be studied in monolayer systems. Here, we established an organoid-derived bronchial culture model that allows physiologically relevant studies on HMPV. Inoculation with multiple prototype HMPV viruses and recent clinical virus isolates led to differences in replication among HMPV isolates. Prolific HMPV replication in this model caused damage to the ciliary layer, including cilia loss at advanced stages post-infection. These cytopathic effects correlated with those observed in previous
in vivo
studies with cynomolgus macaques. The assessment of the innate immune responses in three donors upon HMPV and RSV inoculation highlighted the importance of incorporating multiple donors to account for donor-dependent variation. In conclusion, these data indicate that the organoid-derived bronchial cell culture model resembles
in vivo
findings and is therefore a suitable and robust model for future HMPV studies.

IMPORTANCE

Human metapneumovirus (HMPV) is one of the leading causative agents of respiratory disease in humans, with no treatment or vaccine available yet. The use of primary epithelial cultures that recapitulate the tissue morphology and biochemistry of the human airways could aid in defining more relevant targets to prevent HMPV infection. For this purpose, this study established the first primary organoid-derived bronchial culture model suitable for a broad range of HMPV isolates. These bronchial cultures were assessed for HMPV replication, cellular tropism, cytopathology, and innate immune responses, where the observations were linked to previous
in vivo
studies with HMPV. This study exposed an important gap in the HMPV field since extensively cell-passaged prototype HMPV B viruses did not replicate in the bronchial cultures, underpinning the need to use recently isolated viruses with a controlled passage history. These results were reproducible in three different donors, supporting this model to be suitable to study HMPV infection.
Dietary supplementation with probiotics promotes weight loss by reshaping the gut microbiome and energy metabolism in obese dogs
Authors: Kang Anna , Kwak Min-Jin , Lee Daniel Junpyo , Lee Jeong Jae , Kim Min Kyu , Song Minho , Lee Minjee , Yang Jungwoo , Oh Sangnam , Kim Younghoon 
Published: January 2024

ABSTRACT

Obesity and overweight among companion animals are significant concerns, paralleling the issues observed in human populations. Recent research has highlighted the potential benefits of various probiotics in addressing weight-related changes, obesity, and associated pathologies. In this study, we delved into the beneficial probiotic mechanisms in high-fat-induced obese canines, revealing that
Enterococcus faecium
IDCC 2102 (IDCC 2102) and
Bifidobacterium lactis
IDCC 4301 (IDCC 4301) have the capacity to mitigate the increase in body weight and lipid accumulation in obese canines subjected to a high-fat diet and hyperlipidemic
Caenorhabditis elegans
(
C. elegans
) strain VS29. Both IDCC 2102 and IDCC 4301 demonstrated the ability to reduce systemic inflammation and hormonal disruptions induced by obesity. Notably, these probiotics induced modifications in the microbiota by promoting lactic acid bacteria, including
Lactobacillaceae
,
Ruminococcaceae
, and
S24-7
, with concomitant activation of pyruvate metabolism. IDCC 4301, through the generation of bacterial short-chain fatty acids and carboxylic acids, facilitated glycolysis and contributed to ATP synthesis. Meanwhile, IDCC 2102 produced bacterial metabolites such as acetic acid and butyric acid, exhibiting a particular ability to stimulate dopamine synthesis in a canine model. This stimulation led to the restoration of eating behavior and improvements in glucose and insulin tolerance. In summary, we propose novel probiotics for the treatment of obese animals based on the modifications induced by IDCC 2102 and IDCC 4301. These probiotics enhanced systemic energy utilization in response to high caloric intake, thereby preventing lipid accumulation and restoring stability to the fecal microbiota. Consequently, this intervention resulted in a reduction in systemic inflammation caused by the high-fat diet.

IMPORTANCE
Probiotic supplementation affected commensal bacterial proliferation, and administering probiotics increased glycolysis and activated pyruvate metabolism in the body, which is related to propanate metabolism as a result of pyruvate metabolism activation boosting bacterial fatty acid production via dopamine and carboxylic acid specialized pathways, hence contributing to increased ATP synthesis and energy metabolism activity.