bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigating Viscoelastic Properties of Myofibrils Isolated From hiPSC-CMs Using Atomic Force Microscopy and Quasi-Linear Viscoelastic Model
Authors: Jannati Shayan , Maaref Yasaman , Tibbits Glen F. , Chiao Mu 
Published: August 2023

Abstract
Knowing the mechanical properties of cardiac myofibrils isolated from human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) can provide valuable insight into the structure and function of the heart muscle. Previous studies focused mostly on studying myofibrillar stiffness using simplified elastic models. In this study, the mechanical properties of myofibrils isolated from hiPSC-CMs were measured using atomic force microscopy (AFM). The quasi-linear viscoelastic (QLV) model was used to interpret the elastic and viscous properties of myofibrils. Since there have been no previous studies on the viscoelastic properties of myofibrils extracted from hiPSC-CMs, myofibrils extracted from porcine left-ventricular (LV) tissue were used to compare and verify experimental processes and QLV model parameters. The elastic modulus of myofibrils extracted from porcine LV tissue was determined to be 8.82 ± 6.09 kPa which is consistent with previous studies which reported that porcine LV tissue is less stiff on average than mouse and rat cardiac myofibrils. The elastic modulus of myofibrils extracted from hiPSC-CMs was found to be 9.78 ± 5.80 kPa, which is consistent with the range of 5–20 kPa reported for myofibrils extracted from the adult human heart. We found that myofibrils isolated from hiPSC-CMs relax slower than myofibrils extracted from porcine LV tissue, particularly in the first 0.25 s after the peak stress in the stress relaxation test. These findings provide important insights into the mechanical behavior of hiPSC-CMs and have implications for the development of treatments for heart diseases.
Analysis of Flexoelectric Solids With a Cylindrical Cavity
Authors: Xie Jinchen , Linder Christian 
Published: August 2023

Abstract
Flexoelectricity, a remarkable size-dependent effect, means that strain gradients can give rise to electric polarization. This effect is particularly pronounced near defects within flexoelectric solids, where large strain gradients exist. A thorough understanding of the internal defects of flexoelectric devices and their surrounding multiphysics fields is crucial to comprehend their damage and failure mechanisms. Motivated by this, strain gradient elasticity theory is utilized to investigate the mechanical and electrical behaviors of flexoelectric solids with cylindrical cavities under biaxial tension. Closed-form solutions are obtained under the assumptions of plane strain and electrically impermeable defects. In particular, this study extends the Kirsch problem of classical elasticity theory to the theoretical framework of higher-order electroelasticity for the first time. Our research reveals that different length scale parameters of the strain gradient and bidirectional loading ratios significantly affect the hoop stress field, radial electric polarization field, and electric potential field near the inner cylindrical cavity of the flexoelectric solid. Furthermore, we validate our analytical solution by numerical verification using mixed finite elements. The congruence between the two methods confirms our analytical solution’s accuracy. The findings presented in this paper provide deeper insights into the internal defects of flexoelectric materials and can serve as a foundation for studying more complex defects in flexoelectric solids.
An Incremental Self-Excitation Method for Effectively Identifying Low-Frequency Frequency Response Function of Milling Robots
Authors: Wu Jiawei , Tang Xiaowei , Xin Shihao , Wang Chenyang , Peng Fangyu , Yan Rong , Mao Xinyong 
Published: August 2023

Abstract
Robotic machining efficiency and accuracy are constrained by milling vibrations and chatter. The dynamic characteristics of robots are highly influenced by their poses. Consequently, it is crucial to obtain the robot’s dynamic characteristics in any given pose to mitigate vibrations and prevent chatter during large-range machining. This paper proposes an incremental self-excitation method for effectively identifying low-frequency frequency response functions (FRF) of milling robots. By attaching a mass block at the robot’s end, a fully knowable and controllable excitation increment can be achieved, overcoming the shortcoming of traditional self-excitation methods in capturing the dynamic compliance magnitude. By employing suitable trajectory programming, this method can be executed automatically in the desired poses without the need for manual operations. First, the impulse (moment) of the incremental self-excitation is modeled based on momentum theorem, and the association model of the pulse response increment with the incremental self-excitation is established. To address the issue of sensitivity to noise in the FRF calculation process, the incremental self-excitation is assumed to be a Gaussian pulse, and its identification method is provided. Subsequently, the dimensionality requirement for identifying the nine-item (direct and cross) FRFs is effectively reduced using the modal directionality of milling robots, and the corresponding FRF calculation method is proposed. The rationality of the simplifications and assumptions employed in this method is validated through experiments and calculations. The experimental results in several robot poses show that the proposed method can effectively identify all the direct and cross FRFs in the low-frequency band.
An Investigation of the Thermal Performance of a Tropical Greenhouse Constructed With an Earth Air Heat Exchanger
Authors: Singhal Samar , Yadav Ashwini Kumar , Prakash Ravi 
Published: August 2023

Abstract
To maintain optimum plant growth temperature (i.e., 25–35 °C), the thermal performance of an earth air tunnel heat exchanger (EATHE)-integrated single-span saw-tooth greenhouse (GH) was assessed in peak summer. With the side and roof vents opened, natural ventilation due to wind and stack effect controlled the air movement and temperature inside the GH. In this configuration, the average temperature inside the GH remained higher than the ambient temperature by 1.5 °C for the entire period of the experiment. For EATHE (installed at a depth of 3.2 m) assisted GH with polyethylene (PE) cover, the air from the EATHE outlet entered inside the GH at 33 °C, and the average temperature within the GH was maintained at 4 °C lower than the ambient temperature. When the shading net was installed over the PE cover with the EATHE, the transmitted radiations into the GH were reduced from the roof, and the inside temperature was maintained 7 °C below the average ambient temperature (i.e., 45 °C). The measured temperatures along the length of the EATHE were compared with the indigenously developed code named PEAT (performance analysis of earth–air tunnel) and found to be in good agreement within ±4.5% deviation. The temperature distribution inside the GH was predicted using a computational fluid dynamics (CFD) model in ansys fluent with ±5% deviation from experimental results. With parametric analysis from the PEAT code and CFD model, the desired depth of the EATHE and the mass flowrate of air required to bring down the GH indoor temperatures to the optimum plant growth range were determined.
Analysis and Optimization of a 6-DoF 3-

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P

S Parallel Mechanism for Robot-Assisted Long-Bone Fracture Surgery
Authors: Clancy Michael , Alruwaili Fayez , Saeedi-Hosseiny Marzieh S. , McMillan Sean , Iordachita Iulian I. , Abedin-Nasab Mohammad H. 
Published: August 2023

Abstract
Robot-assisted femur repair has been of increased interest in recent literature due to the success of robot-assisted surgeries and current reoperation rates for femur fracture surgeries. The current limitation of robot-assisted femur fracture surgery is the lack of large force generation and sufficient workspace size in traditional mechanisms. To address these challenges, our group has created a 3-RRPS parallel mechanism, Robossis, which maintains the strength of parallel mechanisms while improving the translational and rotational workspace volume. In this paper, an optimal design methodology of parallel mechanisms for application to robot-assisted femur fracture surgery using a single-objective genetic algorithm is proposed. The genetic algorithm will use a single-objective function to evaluate the various configurations based on the clinical and mechanical design criteria for femur fracture surgery as well as the global conditioning index. The objective function is composed of the desired translational and rotational workspaces based on the design criteria, dynamic load-carrying capacity, and the homogeneous Jacobian global conditioning index. Lastly, experimental results of Robossis were obtained to validate the kinematic solution and the mechanism itself; Robossis had an average error of 0.31 mm during experimental force testing.
Deep spatial profiling of Venezuelan equine encephalitis virus reveals increased genetic diversity amidst neuroinflammation and cell death during brain infection
Authors: Williams Evan P. , Xue Yi , Lee Jasper , Fitzpatrick Elizabeth A. , Kong Ying , Reichard Walter , Writt Haley , Jonsson Colleen B. 
Published: August 2023

ABSTRACT
Venezuelan equine encephalitis virus (VEEV) causes a febrile illness that can progress to neurological disease with the possibility of death in human cases. The evaluation and optimization of therapeutics that target brain infections demands knowledge of the host’s response to VEEV, the dynamics of infection, and the potential for within-host evolution of the virus. We hypothesized that selective pressures during infection of the brain may differ temporally and spatially and so we investigated the dynamics of the host response, viral transcript levels, and genetic variation of VEEV TC-83 in eight areas of the brain in mice over 7 days post-infection (dpi). Viral replication increased throughout the brain until 5–6 dpi and decreased thereafter with neurons as the main site of viral replication. Low levels of genetic diversity were noted on 1 dpi and were followed by an expansion in the genetic diversity of VEEV and nonsynonymous (Ns) mutations that peaked by 5 dpi. The pro-inflammatory response and the influx of immune cells mirrored the levels of virus and correlated with substantial damage to neurons by 5 dpi and increased activation of microglial cells and astrocytes. The prevalence and dynamics of Ns mutations suggest that the VEEV is under selection within the brain and that progressive neuroinflammation may play a role in acting as a selective pressure.

IMPORTANCE
Treatment of encephalitis in humans caused by Venezuelan equine encephalitis virus (VEEV) from natural or aerosol exposure is not available, and hence, there is a great interest to address this gap. In contrast to natural infections, therapeutic treatment of infections from aerosol exposure will require fast-acting drugs that rapidly penetrate the blood-brain barrier, engage sites of infection in the brain and mitigate the emergence of drug resistance. Therefore, it is important to understand not only VEEV pathogenesis, but the trafficking of the viral population within the brain, the potential for within-host evolution of the virus, and how VEEV might evolve resistance.
Construction and Modification of Debris-Flow Alluvial Fans as Captured in the Geomorphic and Sedimentary Record: Examples from the Western Sangre de Cristo Mountains, South-Central Colorado
Authors: Nicovich* Sylvia R. , Schmitt James G. , Gray Harrison J. , Klinger Ralph E. , Mahan Shannon A. 
Published: August 2023

ABSTRACTDebris-flow alluvial fans are iconic features of dynamic landscapes and are hypothesized to record tectonic and climatic change. Here, we highlight their complex formation and evolution through an exemplary suite of Quaternary debris-flow alluvial fans emanating from the western range front of the Sangre de Cristo Mountains in south-central Colorado, USA. To evaluate the constructive and modifying processes that produce fan form and the associated sedimentary signatures, we applied a combined geomorphologic and sedimentologic approach using sedimentary facies analysis, soils mapping, high-resolution topographic data, and luminescence geochronology to document timing of fan construction and modification. We explored two subsets of fans in the study area: a southern set sourced from the extensively glaciated drainages of the Blanca Peak massif, and a northern set from the unglaciated drainages south of Great Sand Dunes National Park. Both sets of fans have: (1) active and successively abandoned surfaces that show evolving degradation of primary features through modification by secondary processes, (2) associated facies that display distinct characteristics representative of primary depositional and secondary modifying sedimentary processes, and (3) evidence of primary debris flow with subsequent modification by secondary processes. We found that surface geomorphology and facies assemblages in exposed alluvial-fan deposits represent sediment transport processes on both active and abandoned lobes. The link between fan surface morphologies and the sedimentary facies of their deposits provides a basis for an evolutionary process–based interpretation of debris-flow alluvial-fan geomorphology and provides a better understanding of complexities in buried paleosurfaces (intraformational progressive unconformities), surficial deformation, and landform development as recorded in debris-flow fan deposits in the sedimentary record.
Predictive performance of the STarT Back tool for poor outcomes in patients with low back pain: protocol for a systematic review and meta-analysis
Authors: Fang Yunhua , Chen Jie , Lin Shengmei , Cai Yangfan , Huang Lian-Hong 
Published: August 2023

IntroductionSubgroups for Targeted Treatment Back Tool (SBT) is a brief multiple-construct risk prediction tool for patients with low back pain (LBP). Thus far, the predictive ability of this tool has been inconsistent. Therefore, we aim to conduct a literature review on the predictive ability of the SBT to determine the outcomes of patients with LBP. The results of this review should improve the ability of the SBT to predict poor outcomes in patients with LBP.Methods and analysisDatabases including PubMed, EMBASE, Cochrane Central, Web of Science, Chinese National Knowledge Infrastructure Databases, Chinese Science and Technology Journal Database, and Wanfang will be searched for studies on SBT and LBP from their inception until 31 March 2023. Longitudinal studies investigating the association between SBT subgroups and LBP outcomes, including pain, disability and quality of life, will be included. The identified studies will be independently screened for eligibility by two reviewers. A standardised sheet will be used to extract data. The Newcastle-Ottawa Scale will be used to assess the methodological quality of the included studies. Heterogeneity will be evaluated by the χ2test with Cochran’s Q statistic and quantified by the I2statistic. The results will be synthesised qualitatively and presented as pooled risk ratios or beta coefficients quantitatively. The results will also be presented using their 95% confidence limits. Publication bias will be assessed using the method proposed by Egger and by visual inspection of funnel plots.Ethics and disseminationThis study is a secondary analysis of original studies that received ethics approval. Therefore, prior ethical approval is not required for this study. The findings will be submitted to relevant peer-reviewed journals for publication and presented at profession-specific conferences.Trial registration numberPROSPERO registration numberCRD42022309189.
Recruiting and retaining bachelor qualified nurses in German hospitals (BSN4Hospital): protocol of a mixed-methods design
Authors: Maier Claudia B , Köppen Julia , Kleine Joan , McHugh Matthew D , Sermeus Walter , Aiken Linda H 
Published: August 2023

IntroductionMany countries in Europe are facing a shortage of nurses and seek effective recruitment and retention strategies. The nursing workforce is increasingly diverse in its educational background, ranging from 3-year vocational training (diploma) to bachelor and master educated nurses. This study analyses recruitment and retention strategies for academically educated nurses (minimum bachelor), including intention to leave, job satisfaction and work engagement compared with diploma nurses in innovative German hospitals; it explores recruitment and retention challenges and opportunities, and identifies lessons on recruitment and retention taking an international perspective.Methods and analysisThe study will apply a convergent mixed-methods design, including qualitative and quantitative methods. The qualitative study will include semistructured interviews among hospital managers, nurses, students and stakeholders in Germany. In addition, expert interviews will be conducted internationally in countries with a higher proportion of bachelor/master nurses in hospitals. The quantitative, cross-sectional study will consist of a survey among professional nurses (bachelor/master, diploma nurses) in German hospitals. Study settings are hospitals with a higher-than-average proportion of bachelor nurses or relevant recruitment, work environment or retention strategies in place. Analyses will be conducted in several phases, first in parallel, then combined via triangulation: the parallel analysis technique will analyse the qualitative and quantitative data separately via content analyses (interviews) and descriptive, bivariate and multivariate analyses (survey). Subsequently, data sources will be collectively analysed via a triangulation matrix focusing on developing thematic exploratory clusters at three systemic levels: microlevel, mesolevel and macrolevel. The analyses will be relevant for generating lessons for clinical nursing, management and policy in Germany and internationally.Ethics and disseminationEthics approval was obtained by the Charité Ethics Committee.Several dissemination channels will be used, including publications and presentations, for the scientific community, nursing management, clinical nurses and the wider public in Germany and internationally.
Improving survival in alcohol-related hepatitis: what's new?
Authors: Shearer Jessica , Johnson Amy , Masson Steven 
Published: August 2023

Alcohol-related hepatitis (AH) is the most florid presentation of alcohol-related liver disease and carries a high short-term and long-term mortality rate. Specific treatment options remain inadequate. The current management approach for AH focuses on early identification, careful screening and treatment of infection, as well as identification of those patients who may benefit from corticosteroid therapy based on validated prognostic scoring systems.In recent years, there has been growing interest in exploring novel therapies for AH, which may offer alternative treatment options beyond the traditional approaches. Additionally, early liver transplantation (LT) has emerged as a promising option in selected cases with growing evidence supporting its role. In this review, we will discuss the current evidence base for the assessment and treatment of AH, and how these advances are shaping practice to improve outcomes in the UK.
Disease-modifying interactions between chronic kidney disease and osteoarthritis: a new comorbid mouse model
Authors: Julovi Sohel M , Dao Aiken , Trinh Katie , O’Donohue Alexandra K , Shu Cindy , Smith Susan , Shingde Meena , Schindeler Aaron , Rogers Natasha M , Little Christopher B 
Published: August 2023

ObjectiveThe prevalence of comorbid chronic kidney disease (CKD) and osteoarthritis (OA) is increasing globally. While sharing common risk factors, the mechanism and consequences of concurrent CKD-OA are unclear. The aims of the study were to develop a preclinical comorbid model, and to investigate the disease-modifying interactions.MethodsSeventy (70) male 8–10 week-old C57BL/6 mice were subjected to 5/6 nephrectomy (5/6Nx)±destabilisation of medial meniscus (DMM) or sham surgery. OA pathology and CKD were assessed 12 weeks postinduction by blinded histology scoring, micro-CT, immunohistochemistry for osteoclast and matrix metalloproteinase (MMP)-13 activity, and serum analysis of bone metabolic markers.ResultsThe 5/6Nx model recapitulated characteristic features of CKD, with renal fibrosis and deranged serum alkaline phosphatase, calcium and phosphate. There was no histological evidence of cartilage pathology induced by 5/6Nx alone, however, synovial MMP-13 expression and subchondral bone osteoclastic activity were increased (p<0.05), with accompanying reductions (p<0.05) in subchondral trabecular bone, bone volume and mineral density. DMM significantly (p<0.05) increased tibiofemoral cartilage damage, subchondral bone sclerosis, marginal osteophytes and synovitis, in association with increased cartilage and synovial MMP-13. DMM alone induced (p<0.05) renal fibrosis, proteinuria and increased (p<0.05) 5/6Nx-induced serum urea. However, DMM in 5/6Nx-mice resulted in significantly reduced (p<0.05) cartilage pathology and marginal osteophyte development, in association with reduced subchondral bone volume and density, and inhibition of 5/6Nx-induced subchondral bone osteoclast activation.ConclusionThis study assessed a world-first preclinical comorbid CKD-OA model. Our findings demonstrate significant bidirectional disease-modifying interaction between CKD and OA.
Pair production of the open superstrings from the parallel-dressed D3-branes in the compact spacetime
Authors: Barghi-Janyar Niloufar , Kamani Davoud 
Published: August 2023

AbstractWe employ the boundary state formalism to compute the pair creation rate of the open superstrings from the interaction of two parallel D3-branes. The branes live in the partially compact spacetime. In addition, they have been dressed with the internal gauge potentials and the Kalb–Ramond field.
How to Build a Fire: The Genetics of Autoinflammatory Diseases
Authors: Zhang Jiahui , Lee Pui Y. , Aksentijevich Ivona , Zhou Qing 
Published: August 2023

Systemic autoinflammatory diseases (SAIDs) are a heterogeneous group of disorders caused by excess activation of the innate immune system in an antigen-independent manner. Starting with the discovery of the causal gene for familial Mediterranean fever, more than 50 monogenic SAIDs have been described. These discoveries, paired with advances in immunology and genomics, have allowed our understanding of these diseases to improve drastically in the last decade. The genetic causes of SAIDs are complex and include both germline and somatic pathogenic variants that affect various inflammatory signaling pathways. We provide an overview of the acquired SAIDs from a genetic perspective and summarize the clinical phenotypes and mechanism(s) of inflammation, aiming to provide a comprehensive understanding of the pathogenesis of autoinflammatory diseases.