bluuebunny/crossref_metadata_2025 huggingface dataset:
Catsnap: a user‐friendly algorithm for determining the conservation of protein variants reveals extensive parallelisms in the evolution of alternative splicing
Authors: Timofeyenko Ksenia , Kanavalau Dzmitry , Alexiou Panagiotis , Kalyna Maria , Růžička Kamil
Published: February 2023

Understanding the evolutionary conservation of complex eukaryotic transcriptomes significantly illuminates the physiological relevance of alternative splicing (AS). Examining the evolutionary depth of a given AS event with ordinary homology searches is generally challenging and time‐consuming.

Here, we present Catsnap, an algorithmic pipeline for assessing the conservation of putative protein isoforms generated by AS. It employs a machine learning approach following a database search with the provided pair of protein sequences.

We used the Catsnap algorithm for analyzing the conservation of emerging experimentally characterized alternative proteins from plants and animals. Indeed, most of them are conserved among other species. Catsnap can detect the conserved functional protein isoforms regardless of the AS type by which they are generated. Notably, we found that while the primary amino acid sequence is maintained, the type of AS determining the inclusion or exclusion of protein regions varies throughout plant phylogenetic lineages in these proteins. We also document that this phenomenon is less seen among animals.

In sum, our algorithm highlights the presence of unexpectedly frequent hotspots where protein isoforms recurrently arise to carry physiologically relevant functions. The user web interface is available at https://catsnap.cesnet.cz/.
Plant water use theory should incorporate hypotheses about extreme environments, population ecology, and community ecology
Authors: Blonder Benjamin Wong , Aparecido Luiza Maria Teophilo , Hultine Kevin R. , Lombardozzi Danica , Michaletz Sean T. , Posch Bradley C. , Slot Martijn , Winter Klaus
Published: February 2023

Plant water use theory has largely been developed within a plant‐performance paradigm that conceptualizes water use in terms of value for carbon gain and that sits within a neoclassical economic framework. This theory works very well in many contexts but does not consider other values of water to plants that could impact their fitness. Here, we survey a range of alternative hypotheses for drivers of water use and stomatal regulation. These hypotheses are organized around relevance to extreme environments, population ecology, and community ecology. Most of these hypotheses are not yet empirically tested and some are controversial (e.g. requiring more agency and behavior than is commonly believed possible for plants). Some hypotheses, especially those focused around using water to avoid thermal stress, using water to promote reproduction instead of growth, and using water to hoard it, may be useful to incorporate into theory or to implement in Earth System Models.
Comparison of Long‐Term Clinical and Radiographical Outcomes between the Anterior and Combined Anterior and Posterior Approaches for Treating Lumbosacral Tuberculosis
Authors: Zhang Zhuang , Hu Bo‐wen , Wang Lin‐nan , Li Tao , Yang Hui‐liang , Liu Li‐min , Song Yue‐ming , Zhou Zhong‐jie
Published: February 2023

Objective

Both anterior and combined anterior and posterior approaches have been used to treat lumbosacral tuberculosis. However, long‐term follow‐up studies of each approach have not been conducted. We aimed to compare the long‐term clinical and radiographical outcomes between the two approaches.

Methods

In this retrospective cohort study, we included 49 patients with a minimum 6‐year follow‐up between January 2008 and March 2012. Twenty‐four patients underwent the anterior approach (anterior group), and 25 underwent the combined anterior and posterior approach (anterior–posterior group). Student's t test, Mann–Whitney U test, and Pearson's chi‐square test were used to compare the two groups regarding clinical data, such as visual analogue scale scores, Oswestry disability index scores and neurological status, and radiographical data, such as lumbosacral angle, lumbar lordosis, and L5‐S1 height. Furthermore, operative time, length of stay, and intraoperative and postoperative blood loss (IBL, PBL) were recorded.

Results

Both groups had satisfactory clinical and radiographical outcomes until the final follow‐up. All patients achieved bony fusion, and no group differences were found in any of the clinical indices. Both groups corrected and maintained the lumbosacral angle, lumbar lordosis, and L5‐S1 height. However, the operative time, length of stay, maximum Hb drop, IBL, and PBL of the anterior group (140.63 ± 24.73 min, 12.58 ± 2.45 days, 28.33 ± 9.70 g/L, 257.08 ± 110.47 ml, and 430.60 ± 158.27 ml, respectively) were significantly lower than those of the anterior–posterior group (423.60 ± 82.81 min, P < 0.001; 21.32 ± 3.40 days, P < 0.001; 38.48 ± 8.03 g/L, P < 0.001; 571.60 ± 111.04 ml, P < 0.001; and 907.01 ± 231.99 ml, P < 0.001).

Conclusion

This retrospective study demonstrated long‐term efficacy of the anterior approach with a single screw fixation, which was as effective as that of the combined anterior and posterior approach, with the advantage of less trauma.
Clinical outcomes of subcutaneous implantable cardiac defibrillator implantation – Iran SICD registry
Authors: Mehdinejadshani Mahdiye , Fallah Hamidreza , Kamali Farzad , Alizadeh‐Diz Abolfath , Eslami Masoud , Golabchi Allahyar , Taherpour Mehdi , Shahabi Javad , Mollazadeh Reza , Madadi Shabnam , Azhari Amir , Sodagar Abdolhossein , Eftekharzadeh Mahmoud , Oraii Saeed , Fazelifar Amirfarjam , Kazemisaeed Ali , Ghorbanisharif Alireza , Dalili Mohammad , Khorgami Mohammadrafie , Heidari‐Bakavoli Alireaza , Jorat Mohammadvahid , Nikoo Hossein , Kheirkhah Jalal , Saravi Mehrdad , Khodaparast Morteza , Mirzaali Mansour , Emkanjoo Zahra , Mirmasoumi Mehrdad , Sadeghian Saeed , Mokhtari Meisam , Hedayati‐Goudarzi Mohammadtaghi , Haghjoo Majid
Published: February 2023

Background

The subcutaneous implantable‐defibrillator (S‐ICD) is a relatively new alternative to the transvenous ICD system to minimize intravascular lead‐related complications. This paper presents outcome of SICD implantation in patients enrolled in Iran S‐ICD registry.

Methods

Between October 2015 and June 2022, this prospective multicenter national registry included 223 patients with a standard indication for an ICD, who neither required bradycardia pacing nor needed cardiac resynchronization to evaluate the early post‐implant complications and long‐term follow‐up results of the S‐ICD system.

Results

The mean age of the patients was 45 ± 17 years. The majority (79.4%) were male. Ischemic cardiomyopathy (39.5%) was the most common underlying disorder among patients selected for S‐ICD implant. Most study patients (68.6%) had ICD for primary prevention of sudden cardiac death. Seven patients (3.1%) were found to have suboptimal lead positions. Six patients (2.7%) developed a pocket hematoma; all were managed medically. During a mean follow‐up of 2 years, the appropriate therapy was recorded in 13% of the patients and inappropriate ICD intervention mainly due to supraventricular tachycardia in 8.9%. Pocket infection was observed in four patients (1.8%) and five patients (2.2%) died mainly due to heart failure.

Conclusion

S‐ICDs were effective at detecting and treating both induced and spontaneous ventricular arrhythmias. Major clinical complications were rare.
A novel R2R3‐MYB transcription factor FaMYB5 positively regulates anthocyanin and proanthocyanidin biosynthesis in cultivated strawberries (Fragaria × ananassa)
Authors: Jiang Leiyu , Yue Maolan , Liu Yongqiang , Zhang Nating , Lin Yuanxiu , Zhang Yunting , Wang Yan , Li Mengyao , Luo Ya , Zhang Yong , Wang Xiaorong , Chen Qing , Tang Haoru
Published: February 2023

Flavonoids have a major contribution to the fruit quality in cultivated strawberries and are regulated by MYB, bHLH and WD40 transcriptional factors. We reported here the identification of the FaMYB5, an R2R3‐MYB transcription factor, which positively regulated the accumulation of anthocyanins and proanthocyanidins through the trans‐activation of the F3'H and LAR. The strawberry FaEGL3 and FaLWD1/FaLWD1‐like interact with the R2R3‐FaMYB5 to form an MYB‐bHLH‐WD40 complex (MBW), enhancing the regulatory efficiency. The R2R3‐FaMYB5 was constitutively expressed in various tissues and in fruits of different developmental stages, which was strikingly contrasting to the fruit‐specific expression patterns of FaMYB10. Meanwhile, R2R3‐FaMYB5 failed to promote a stable accumulation of anthocyanin glycosides in the mature fruits of the myb10 mutant, mainly due to the suppressed expression of TT19. The R2R3‐FaMYB5 was regulated by an antisense long noncoding RNA lncRNA‐myb5. Additionally, the R2R3‐FaMYB5 protein could interact with FaBT2 and was degraded through the ubiquitin/26 S proteasome pathway. Transcriptome and metabolome data showed that R2R3‐FaMYB5 enhanced the gene expression and the metabolite accumulation involved in the flavonoid, phenylpropanoid and lignin biosynthesis pathways. Collectively, we conclude that the FaMYB5 is an R2R3‐MYB activator involved in the composition of MBW, which positively regulates the biosynthesis of anthocyanin and proanthocyanidin. These findings provided new insights into the molecular mechanisms that regulate flavonoids in strawberry fruits.
Temporal trends in primary payers in pediatric heart transplant and association with long‐term survival
Authors: Restaino Kathryn , Zhang Xuemei , Faerber Jennifer A. , Rossano Joseph W. , Burstein Danielle , Wittlieb‐Weber Carol A. , Lin Kimberly Yee , Edelson Jonathan B. , Edwards Jonathan J. , O'Connor Matthew J.
Published: February 2023

Background

Pediatric heart transplantation (HT) is resource intensive. In adults, there has been an increase in the proportion of HTs funded by public insurance, with post‐HT outcomes inferior to those funded by private sources. Trends in the funding of pediatric HT and outcomes in children have not been described.

Methods

We queried the United Network for Organ Sharing (UNOS) database for children (<18 years) listed for and undergoing HT between 2004 and 2021. We identified the primary payer at listing, HT, 1 year, and 1–5 years following HT. Trends were analyzed using generalized logit models. Multivariable‐extended Cox regression models were used to test the relationship between insurance type at the time of transplant and time to death or re‐transplant.

Results

There were 6382 pediatric patients who underwent transplants and had either public or private insurance at the time of transplant. The percentage of patients with public insurance at the time of HT increased over time. Public insurance at the time of HT was associated with an increased risk of death or re‐transplant beyond 2 months after HT (adjusted HR at 6 months = 1.43, 95% CI: 1.13–1.81, p = .003; adjusted HR at 9 months = 1.67, 95% CI: 1.17–2.37, p = .004).

Conclusion

There has been a statistically significant trend toward increasing public insurance for children awaiting, at the time of, and after HT. Black patients and those with public insurance at HT have worse long‐term outcomes. This study highlights ongoing disparities in pediatric HT and the need to focus efforts on achieving equitable outcomes.
Misconceptions, Misinformation, and Misperceptions: A Case for Removing the “Mis‐” When Discussing Contraceptive Beliefs
Authors: Stevens Rose , Machiyama Kazuyo , Mavodza Constancia Vimbayi , Doyle Aoife M.
Published: February 2023

Beliefs about contraception are commonly conceptualized as playing an important role in contraceptive decision‐making. Interventions designed to address beliefs typically include counseling to dispel any “myths” or “misconceptions.” These interventions currently show little evidence for impact in reducing beliefs. This commentary delves into the problems associated with using implicitly negative terminology to refer to contraceptive beliefs, which come laden with assumptions as to their validity. By conceptualizing women as getting it wrong or their beliefs as invalid, it sets the scene for dubious treatment of women's concerns and hampers the design of fruitful interventions to address them. To replace the multitude of terms used, we suggest using “belief” going forward to maintain value‐free curiosity and remove any implicit assumptions about the origin or validity of a belief. We provide recommendations for measuring beliefs to help researchers understand the drivers and impacts of the belief they are measuring. Finally, we discuss implications for intervention design once different types of belief are better understood. We argue that tailored interventions by belief type would help address the root causes of beliefs and better meet women's broader contraceptive needs, such as the need for contraceptive autonomy and satisfaction.
The incidence rate of ACL injuries and ankle sprains in basketball players: A systematic review and meta‐analysis
Authors: Stojanović Emilija , Faude Oliver , Nikić Miloš , Scanlan Aaron T. , Radovanović Dragan , Jakovljević Vladimir
Published: February 2023

Objective

To quantify the incidence rate of anterior cruciate ligament (ACL) injuries and ankle sprains according to player sex, playing level, and exposure setting (training vs. games) in basketball players.

Methods

PubMed, MEDLINE, Google Scholar, and ScienceDirect were searched. Only studies reporting the number of ACL injuries and/or ankle sprains alongside the number of athlete‐exposures (training sessions and/or games) in basketball players were included.

Results

Thirty studies (17 reporting ACL injuries and 16 reporting ankle sprains) were included in the meta‐analysis. Higher (p < 0.05) ACL injury incidence rates per 1000 athlete‐exposures were recorded in females (female: 0.20 95% confidence intervals [0.16–0.25]; male: 0.07 [0.05–0.08]; female‐to‐male ratio: 3.33 [3.10–3.57]), in players competing at higher playing levels (amateur: 0.06 [0.04–0.09]; intermediate: 0.16 [0.13–0.20]; elite: 0.25 [0.14–0.64]), and in games (games: female, 0.27 [0.21–0.32]; male, 0.06 [0.03–0.08]; training: female, 0.03 [0.02–0.05]; male: 0.01 [0.00–0.02]; game‐to‐training ratio: 7.90 [4.88–12.91]). Higher (p < 0.05) ankle sprain incidence rates per 1000 athlete‐exposures were observed in males (female: 0.82 [0.61–1.03]; male: 0.90 [0.61–1.19]; female‐to‐male ratio: 0.91 [0.83–0.99]), in players competing at higher playing levels (amateur: 0.54 [0.51–0.57]; intermediate: 1.12 [1.00–1.24]; elite: 1.87 [1.29–2.46]), and in games (games: 2.51 [1.85–3.16]; training: 0.80 [0.52–0.80]; game‐to‐training ratio: 2.77 [2.35–3.26]).

Conclusion

According to player sex, ACL injury incidence rate is higher in females, while ankle sprain incidence rate is greater in males. ACL injury and ankle sprain incidence rates are greater in players competing at higher playing levels and during games compared to training.
Characterization of the novel HLA‐DRB1*11:283 allele
Authors: Dong Lina , Li Ying , Chen Nanying , Zhang Wei , Zhu Faming
Published: February 2023

HLA‐DRB1*11:283 differs from HLA‐DRB1*11:266 by two nucleotide substitutions in exon 2.
Cooperative role of AtRsmD and AtRimM proteins in modification and maturation of 16S rRNA in plastids
Authors: Liu Kaiwei , Lee Keun Pyo , Duan Jianli , Kim Eun Yu , Singh Rahul Mohan , Di Minghui , Meng Zhuoling , Kim Chanhong
Published: February 2023

Chloroplast pre‐ribosomal RNA (rRNA) undergoes maturation, which is critical for ribosome assembly. While the central and auxiliary factors in rRNA maturation have been elucidated in bacteria, their mode of action remains largely unexplored in chloroplasts. We now reveal chloroplast‐specific factors involved in 16S rRNA maturation, Arabidopsis thaliana orthologs of bacterial RsmD methyltransferase (AtRsmD) and ribosome maturation factor RimM (AtRimM). A forward genetic screen aimed to find suppressors of the Arabidopsis yellow variegated 2 (var2) mutant defective in photosystem II quality control found a causal nonsense mutation in AtRsmD. The substantially impaired 16S rRNA maturation and translation due to the mutation rescued the leaf variegation phenotype by lowering the levels of chloroplast‐encoded proteins, including photosystem II core proteins, in var2. The subsequent co‐immunoprecipitation coupled with mass spectrometry analyses and bimolecular fluorescence complementation assay found that AtRsmD interacts with AtRimM. Consistent with their interaction, loss of AtRimM also considerably impairs 16S rRNA maturation with decelerated m2G915 modification in 16S rRNA catalyzed by AtRsmD. The atrimM mutation also rescued var2 mutant phenotypes, corroborating the functional interplay between AtRsmD and AtRimM towards modification and maturation of 16S rRNA and chloroplast proteostasis. The maturation and post‐transcriptional modifications of rRNA are critical to assembling ribosomes responsible for protein translation. Here, we revealed that the cooperative regulation of 16S rRNA m2G915 modifications by AtRsmD methyltransferase and ribosome assembly factor AtRimM contributes to 16S rRNA maturation, ribosome assembly, and proteostasis in chloroplasts.
Reducing perioperative red blood cell unit issue orders, returns, and waste using failure modes and effects analysis
Authors: Lou Sunny S. , Dewey Megan M. , Bollini Mara L. , Harford Derek R. , Ingold Cindy , Wildes Troy S. , Stevens Tracey W. , Martin Jackie L. , Grossman Brenda J. , Kangrga Ivan
Published: February 2023

Background

Surgical transfusion has an outsized impact on hospital‐based transfusion services, leading to blood product waste and unnecessary costs. The objective of this study was to design and implement a streamlined, reliable process for perioperative blood issue ordering and delivery to reduce waste.

Study Design and Methods

To address the high rates of surgical blood issue requests and red blood cell (RBC) unit waste at a large academic medical center, a failure modes and effects analysis was used to systematically examine perioperative blood management practices. Based on identified failure modes (e.g., miscommunication, knowledge gaps), a multi‐component action plan was devised involving process changes, education, electronic clinical decision support, audit, and feedback. Changes in RBC unit issue requests, returns, waste, labor, and cost were measured pre‐ and post‐intervention.

Results

The number of perioperative RBC unit issue requests decreased from 358 per month (SD 24) pre‐intervention to 282 per month (SD 16) post‐intervention (p < .001), resulting in an estimated savings of 8.9 h per month in blood bank staff labor. The issue‐to‐transfusion ratio decreased from 2.7 to 2.1 (p < .001). Perioperative RBC unit waste decreased from 4.5% of units issued pre‐intervention to 0.8% of units issued post‐intervention (p < .001), saving an estimated $148,543 in RBC unit acquisition costs and $546,093 in overhead costs per year.

Discussion

Our intervention, designed based on a structured failure modes analysis, achieved sustained reductions in perioperative RBC unit issue orders, returns, and waste, with associated benefits for blood conservation and transfusion program costs.
On the Effects of Optimal Implementation of Variable Rotor Speed and Power Management on Hybrid-Electric Rotorcraft
Authors: Saias Chana Anna , Goulos Ioannis , Pachidis Vassilios , Bacic Marko
Published: February 2023

The concept of variable rotor speed (VRS) has been recognized as an efficient means to improve rotorcraft operational performance and environmental impact, with electrification being a potential technology to further contribute to that. This paper explores the impact of optimal implementation and scheduling of VRS and power management strategy for conventional and hybrid-electric rotorcraft on energy, fuel, and emissions footprint. A multidisciplinary simulation framework for rotorcraft performance combined with models for engine performance and gaseous emissions estimation is deployed. A holistic optimization approach is developed for the derivation of globally optimal schedules for combined rotor speed and power split targeting minimum energy consumption. Application of the derived optimal schedules at mission level resulted to a 6% improvement in range capability for the VRS tilt-rotor relative to its conventional counterpart. For the hybrid-electric tilt-rotor, combined optimization of VRS and power management leads to an increase in range to 18.4% at 40% and 25% reduced payload for current (250 Wh/kg) and future (450 Wh/kg) battery technology, respectively. For representative urban air mobility (UAM) scenarios, it is demonstrated that the VRS concept resulted in up to 10% and 14% reductions in fuel burn and NOx relative to the nominal rotor speed case, respectively. The utilization of the combined optimum VRS and power split schedules can boost performance with reductions of the order of 20% and 25% in mission fuel/CO2 and NOx at a reduced payload relative to the conventional tilt-rotor.
Numerical Simulation for Generalized Time-Fractional Burgers' Equation With Three Distinct Linearization Schemes
Authors: Chawla Reetika , Deswal Komal , Kumar Devendra , Baleanu Dumitru
Published: February 2023

In the present study, we examined the effectiveness of three linearization approaches for solving the time-fractional generalized Burgers' equation using a modified version of the fractional derivative by adopting the Atangana-Baleanu Caputo derivative. A stability analysis of the linearized time-fractional Burgers' difference equation was also presented. All linearization strategies used to solve the proposed nonlinear problem are unconditionally stable. To support the theory, two numerical examples are considered. Furthermore, numerical results demonstrate the comparison of linearization strategies and manifest the effectiveness of the proposed numerical scheme in three distinct ways.
Optimal Design and Experiment of Cable-Driven Puncturing Surgery Robot for Soft Needle
Authors: Li Jihua , Jiang Qi
Published: February 2023

In this paper, a cable-driven puncturing surgery robot named cable-driven puncturing surgery robot (CPSR) is proposed for soft needle. The cable-driven mechanism has lower mass, smaller dimension and smooth transmission. The motor driving the rotational joints is separated using cable, which strengthens the dynamic performance of the robot. A decoupling mechanism based on movable pulley is also proposed to eliminate the cable coupling error. Transmission error of cable-driven mechanism is also analyzed to improve the control accuracy. The simulation of transmission error is completed to optimize the design parameters of cable-driven mechanism. In experiments, the feasibility of the cable decoupling mechanism is validated. Also the insertion error less than 0.7 mm and repeatability less than 2.5 mm are achieved. Finally the reasons limiting the accuracy and corresponding solutions are discussed. In the future research, the shape sensor will be fabricated using optic fiber and mounted on the slim needle which are helpful to complete automated operations with higher accuracy.
Cable Tension Optimization for an Epicardial Parallel Wire Robot
Authors: Ladak Aman , Hajjar Roger J. , Murali Srinivas , Michalek Jeremy J. , Riviere Cameron N.
Published: February 2023

HeartPrinter is a novel under-constrained 3-cable parallel wire robot designed for minimally invasive epicardial interventions. The robot adheres to the beating heart using vacuum suction at its anchor points, with a central injector head that operates within the triangular workspace formed by the anchors, and is actuated by cables for multipoint direct gene therapy injections. Minimizing cable tensions can reduce forces on the heart at the anchor points while supporting rapid delivery of accurate injections and minimizing procedure time, risk of damage to the robot, and strain to the heart. However, cable tensions must be sufficient to hold the injector head's position as the heart moves and to prevent excessive cable slack. We pose a linear optimization problem to minimize the sum of cable tension magnitudes for HeartPrinter while ensuring the injector head is held in static equilibrium and the tensions are constrained within a feasible range. We use Karush-Kuhn-Tucker optimality conditions to derive conditional algebraic expressions for optimal cable tensions as a function of injector head position and workspace geometry, and we identify regions of injector head positions where particular combinations of cable tensions are optimally at minimum allowable tensions. The approach can rapidly solve for the minimum set of cable tensions for any robot workspace geometry and injector head position and determine whether an injection site is attainable.
Diffusivity of Human Cartilage Endplates in Healthy and Degenerated Intervertebral Disks
Authors: Ren Pengling , Chen Peng , Reeves Russell A. , Buchweitz Nathan , Niu Haijun , Gong He , Mercuri Jeremy , Reitman Charles A. , Yao Hai , Wu Yongren
Published: February 2023

The cartilage endplates (CEPs) on the superior and inferior surfaces of the intervertebral disk (IVD), are the primary nutrient transport pathways between the disk and the vertebral body. Passive diffusion is responsible for transporting small nutrient and metabolite molecules through the avascular CEPs. The baseline solute diffusivities in healthy CEPs have been previously studied, however alterations in CEP diffusion associated with IVD degeneration remain unclear. This study aimed to quantitatively compare the solute diffusion in healthy and degenerated human CEPs using a fluorescence recovery after photobleaching (FRAP) approach. Seven healthy CEPs and 22 degenerated CEPs were collected from five fresh-frozen human cadaveric spines and 17 patients undergoing spine fusion surgery, respectively. The sodium fluorescein diffusivities in CEP radial and vertical directions were measured using the FRAP method. The CEP calcification level was evaluated by measuring the average X-ray attenuation. No difference was found in solute diffusivities between radial and axial directions in healthy and degenerated CEPs. Compared to healthy CEPs, the average solute diffusivity was 44% lower in degenerated CEPs (Healthy: 29.07 μm2/s (CI: 23.96–33.62 μm2/s); degenerated: 16.32 μm2/s (CI: 13.84–18.84 μm2/s), p < 0.001). The average solute diffusivity had an inverse relationship with the degree of CEP calcification as determined by the normalized X-ray attenuation values (ß = −22.19, R2 = 0.633; p < 0.001). This study suggests that solute diffusion through the disk and vertebral body interface is significantly hindered by CEP calcification, providing clues to help further understand the mechanism of IVD degeneration.
Skin Cooling of Turbine Airfoils by Single Wall Effusion: Part I—Reduced Order Modeling
Authors: Lange Yair , Kırmızıgöl S. Fatih , Acarer Sercan , Cukurel Beni
Published: February 2023

A quasi-1D conjugate reduced order model (ROM) is developed to capture aero-thermal physics of effusion cooling in turbine airfoils. This framework explicitly considers the coolant supply from the leading edge and its distribution to both suction and pressure sides, the internal boundary layer flow between the shell and the inner core, the hole flow, the conduction on the solid walls, as well as the external film coverage. The solid temperature is allowed to vary both in metal shell thickness and the streamwise directions. Empirical correlations are employed to model pressure loss and heat transfer in the internal sections. Compound effect of multiple effusion cooling rows are utilized to capture cooling effectiveness and the heat load. Influence of mainstream static pressure, varying blowing ratios, hole’s diameter, hole’s pitch, coolant total pressure, and total temperature distributions along streamwise direction are taken into account. In Part I, the development and validation of the model is presented, which is shown to be capable of capturing complex internal aero-thermal physics of a turbine airfoil. Film coverage capability is separately validated successfully against available flat plate experimental data, with one case including internal channel and metal conduction. In Part II of this work, effusion cooling configuration is applied over an entire micro turbine vane and an exemplary optimization is carried out in the design space to minimize coolant flow while retaining metal temperature and its gradient below some limits. It is shown in the two-part work that the developed model is suitable for parametric studies of single-wall effusion turbine cooling such that comparative accuracy is obtained at a computational time 105 times lower than computational fluid dynamics (CFD) on a whole turbine vane/blade. Together, these two papers are intended to present, validate, and optimize the ROM for skin cooling in turbine airfoils by single-wall effusion.
Quality Control Study on 3D Printed Parts
Authors: Jackson Brandon , Fouladi Kamran , Eslami Babak
Published: February 2023

During the past several decades, additive manufacturing (i.e., 3D printing) has attracted attention from different fields such as design, manufacturing, aerospace, robotics, construction, biomedical, or even the food industry. As 3D printing is transitioning from being just a prototyping capability in the product development process to a final product fabrication capability, there is a need to increase the knowledge of both regular and professional 3D printing users to enhance printing quality. This work has focused on understanding the effect of printing conditions on the final quality of 3D printed parts from both visual and strength aspects. Specifically, we have focused on print deposition angle, the number of shell walls, and retraction speed. Additionally, a micro-scale characterization is performed to better understand the behavior of 3D printing polymers under different relative humidities. It is found that the number of walls does not show any conclusive pattern on the quality and strength of the parts. However, if selected properly, retraction speed and deposition angle could improve the final quality. The most optimum printing condition with maximum ultimate tensile strength is to be with two shell walls, a retraction speed of 75 mm/s and 0 degrees angle of deposition. Additionally, it is found the lower relative humidity during the prints can enhance the strength of filament bonding.
The Optimal Geometric Arrangement of Heat Pipes in Computer CPU Coolers
Authors: Das Shuva , Molki Majid
Published: February 2023

A computer central processing unit (CPU) cooler keeps the CPU at a safe operating temperature. Specifically, this study investigates an air-cooled CPU cooler. Heat pipes carry the CPU’s heat to an array of plate fins which eventually transfer the thermal energy to the outside air. Convective heat transfer in the inter-fin air gaps and conduction within the fins make this cooling a conjugate heat transfer process. Thus, the selected geometry’s conjugate heat transfer solution provides a Nusselt number correlation. The location of the heat pipe is a subtle and significant factor that affects the heat rate at those boundaries and is rarely available in the literature. Depending on the location of heat pipes for a certain Reynolds number, the heat rate could be as high as 3.75% more than the heat rate due to their original locations. A high heat rate indicates an increase in heat transfer for a heat pipe location relative to another. Ultimately, this investigation predicts an optimal geometric arrangement for the location of the heat pipes. The optimal layout of heat pipes is essential to designing thermally efficient CPU coolers.
Analysis of Inequality Constraints Without Using Lagrange Multipliers With Applications to Classical Dynamical Systems
Authors: McCann Brennan S. , Nazari Morad , Udwadia Firdaus
Published: February 2023

The fundamental equation of mechanics (FEM) for constrained motion analysis provides a way to obtain control accelerations necessary to satisfy some set of holonomic or non-holonomic constraints. The methodology provides the control necessary to either perfectly satisfy or minimize the error in all the constraints and does not require computation of Lagrange multipliers. Furthermore, this framework is capable of addressing various types of constraints, and can treat systems that are under-, fully-, or over-constrained, conveniently. The FEM formulation has most commonly been applied to a variety of classes of equality constraints. Some attempts at extending this approach to inequality constraints have been presented in the literature, including applying slack variables to provide freedom in the constraint and diffeomorphisms to map equality constraints to bounded spaces. However, these approaches have different associated advantages and drawbacks. In order to bridge the benefits of both methodologies and mitigate their issues, this work proposes a treatment of holonomic inequality constraints within the framework of the FEM wherea class of functions built on the error and Gaussian distribution functions is leveraged to treat inequality constraints on several classical dynamical case studies. The proposed technique is applied to several classes of holonomic, solitary or one-sided inequalities, and bounding inequalities for a spring-mass-damper, an inverted pendulum, and an inverted pendulum on a cart, illustrating this approach’s broad applicability to mechanical systems.
Analyzing the Process of Seaweed Drying in a Drying Cabinet
Authors: Nazemi Mohiodin , Unnþórsson Rúnar , Richter Christiaan
Published: February 2023

Seaweed is a promising organic fuel source due to its rapid growth rates, efficiency as a carbon sink, and pH resistance. It is a potential renewable fuel source since it can be transformed into high-value fuel by using either thermochemical processes such as gasification, or anaerobic digestion. However, drying the seaweed is necessary to combust, pyrolyze, or gasify seaweed. In this study, we focus on the drying process. To address this, a biomass drying cabinet was designed, constructed, tested, and experimentally evaluated. During drying runs, the temperature inside the cabinet and the moisture content of seaweed were measured. The goal of this design was to reduce the moisture content of seaweed to the optimal range for gasification-between 15% to 20%. We demonstrate the drying of fresh seaweed with an initial moisture content of around 80% to as low as 12% after 22 hours. Bladderwrack is the type of seaweed that is used in this study. Based on the results of the tests, around 19 hours of drying is needed to reduce the moisture content of seaweed to the target range (15%–20%). In conclusion, moisture reduction in Bladderwrack seaweed was analyzed and the design of the seaweed drying cabinet was evaluated. Based on our results modifications to achieve more homogeneous drying throughout the cabinet are proposed.
Unified Constitutive Modeling of Haynes 230 for Thermomechanical Fatigue-Creep and Creep Behavior
Authors: Cao Wenyu , Zhang Hualiang
Published: February 2023

Research on the macroscopic phenomenological constitutive model of Haynes 230, which is frequently used as an aero engine combustor liner material, still has important engineering significance. Based on a proposed model for isothermal fatigue and fatigue-creep, a constitutive model is developed which can simulate the thermomechanical fatigue-creep and pure creep behaviors. The results of simulation and experiment are in good agreement with each other under thermomechanical fatigue-creep loads for the hysteresis loops at half-life, the stress amplitude and the mean stress evolution, or the stress relaxation during dwell time. Good results are also obtained in the case of pure creep. Meanwhile, the simulation of isothermal fatigue and fatigue-creep also maintains high accuracy. The main contribution of this paper is to propose a robust unified constitutive model that has the adaptability to a wide range of temperature variations and is suitable for various types of fatigue-creep interaction loads.
On Fabrication of Patterned Form-Tools Using the Chemically Etched-Tool Electrode
Authors: Tiwari Tanmay , Dvivedi Akshay , Kumar Pradeep
Published: February 2023

Miniaturization of the products is a field of interest that includes several conventional to advanced micro-manufacturing processes. Micro-forming is one of the processes among the other micro-manufacturing process, which is a well-suited technology capable of producing small metallic parts with better material properties. However, several limitations are required to be addressed. Present research work is focused on addressing the limitation of tool design for the tools used in forming process. In current work, a patterned tool is used to fabricate form-tools, using an Electric discharge machining process, which can be used in the micro-forming process. Machining involves the thermal energy transfer, which in turn alters the surface characteristics; therefore, surface roughness obtained after the machining process has been analyzed using the OFAT approach. Gap voltage (Gv), peak current (Pk), pulse-on (Ton), and pulse-off time (Toff) are considered for the analysis over the response, i.e. average surface roughness (Ra). Different patterns viz. Diamond and circular shapes were considered for study along with the design of the Tesla T45A single valve to analyze the applicability of the developed process to fabricate form tools with desired geometry. All the patterns were successfully obtained over the Inconel 718 alloy work material used in the present work.
A Methodology for Digital Twins of Product Lifecycle Supported by Digital Thread
Authors: Monnier Laetitia V. , Shao Guodong , Foufou Sebti
Published: February 2023

Technological advancements have led to the transition of manufacturing industries to Smart Manufacturing and Industry 4.0. Promising concepts such as Digital Twin and Digital Thread could help speed up the transition. One benefit of using digital twins is to enable continuity of lifecycle information. However, currently, most digital-twin implementations focus on modeling a particular lifecycle stage of a physical element in “silos”. This makes companies missing out on up to 65% of possible value of digital twin investments. This also results in it challenging to incorporate diverse data streams from different lifecycle stages. Digital thread has been used to represent information flow along the product lifecycle. Using information across product lifecycle stages will facilitate interoperability and reusability of digital twins. Because data from each lifecycle stage could be accessed and managed systematically, this will ensure the value and the credibility of the digital twin. A lot of confusion still remains in industry about what are digital twin and digital thread as well as their relationships. Using lifecycle data from a digital thread for digital twin implementation is complex because of the heterogeneity of standards and technologies involved. In this paper, we provide definitions of both digital twin and digital thread; we highlight the benefit of using them for interoperability and reusability of a digital twin for product lifecycle management and analysis; we propose a methodology for implementing digital twins using lifecycle data supported by a digital thread. Finally, we showcase the proposed methodology by providing an example of integrating digital twins with a digital thread.
Uncertainty Quantification in Material Properties of Additively Manufactured Materials for Application in Topology Optimization
Authors: Kazemi Zahra , Steeves Craig A.
Published: February 2023

This research presents an approach to measuring the inherent randomness in properties of materials fabricated by the fused filament fabrication (FFF) method. Defects associated with the layer-by-layer process introduce significant variability in the elastic modulus field of materials printed. To describe the random distribution in Young’s modulus fields, statistical properties of mean, variance, and correlation length must be estimated for bulk regions (the printed filaments) and fusion regions (the thin regions connecting printed filaments). The goal is to estimate the random properties from the surface strain fields calculated by digital image correlation (DIC) analysis. A machine learning algorithm is developed that can estimate the spatial variations in the elastic modulus. The model is trained on a dataset of simulated two-dimensional strain fields with known random distributions in the corresponding elastic modulus fields generated by finite element (FE) simulations. On the test data, we achieved the R2 score of 0.93 and 0.95 for the mean in the bulk and fusion Young’s modulus fields, respectively. Also, for the variance in bulk and fusion areas, the R2 score of 0.74 and 0.83 are achieved, respectively. The results demonstrate the feasibility of the proposed approach in measuring the randomness in material properties of FFF-based printed materials.
Development of a Compliant Gripper Driven by 3 DOF Soft Robot
Authors: Ramirez Ricardo , Tran Pt Angel , Price Derek , Amiri Moghadam Amir Ali , Tekes Ayse
Published: February 2023

This study presents the design, development, and experimental testing of a single piece designed compliant gripper manipulated by a 3 DOF soft robot. The manipulator consists of two soft links. While the bottom arm is 2 DOF and is tendon driven by two servo motors, the SDOF upper arm is also tendon driven by a servo motor. The two-finger-designed compliant gripper is also actuated by a servo motor. The base of the robot holds the motors and the soft manipulator. The MATLAB Simscape model of the robot is created to perform deformation and motion analysis of the gripper and soft manipulator. The cad model of the robot is imported, and the manipulator parts are converted into soft links using discrete beam elements. The large deflecting hinges on the compliant grippers are also transformed to mimic the physical gripper. Since the soft manipulator and the compliant gripper were designed monolithically, the robot was 3D printed as a single piece using thermoplastic polyurethane (TPU). The gripper is tested for its grasping and lifting performance while recording the applied forces by the gripper using a Flex sensor. Using the opencv tool for image processing and object analysis, we used a dual-camera setup with a known environment to add intelligence to the robot. Since the manipulator is designed as soft, the gripper can reach any position within its working space with any orientation.
An Inflatable Soft Crawling Robot With Nondestructive Testing Capability for Overhead Power Line Inspection
Authors: Mendoza Nicolás , Nemati Hamidreza , Haghshenas-Jaryani Mahdi , Dehghan-Niri Ehsan
Published: February 2023

This paper presents designing and prototyping of an inflatable soft crawling robot equipped with nondestructive testing (NDT) sensing capability for inspection and diagnosis of potential mechanical faults in overhead power cables. The soft robot is comprised of two gripping modules with radial expansion/contraction, one at the proximal and the other one at the distal end, and a longitudinal contractile-expandable driving module in-between for providing a bi-directional crawling movement. The robot and its soft actuators are made of fabrics and can be wrapped around the power line cables for navigation. The main novelty of the current robotic inspection platform is to integrate the mobility component with an NDT sensing system. Conceptual designs and CAD models of the robot parts, textile-based inflatable structures, and the pneumatic driving mechanisms were developed. The mechanical parts were fabricated using advanced and conventional manufacturing techniques. An Arduino-based electropneumatic control board was developed including proper pneumatic circuits, pumps, sensors, and batteries. The fabricated parts were assembled to create the initial prototype of the soft robot. Control algorithms were developed for the operation of the robot. The prototyped mechanism was tested in a laboratory setting while the collected data were used for modifying the designs, and controlling software and hardware. The feasibility of the proposed robot for cable crawling and multimodal NDT sensing was successfully demonstrated.
Investigations Into Uncertain Control Co-Design Implementations for Stochastic in Expectation and Worst-Case Robust
Authors: Azad Saeed , Herber Daniel R.
Published: February 2023

As uncertainty considerations become increasingly important aspects of concurrent plant and control optimization, it is imperative to identify and compare the impact of uncertain control co-design (UCCD) formulations on their associated solutions. While previous work has developed the theory for various UCCD formulations, their implementation, along with an in-depth discussion of the structure of UCCD problems, implicit assumptions, method-dependent considerations, and practical insights, is currently missing from the literature. Therefore, in this study, we address some of these limitations by proposing two optimal control structures for UCCD problems that we refer to as the open-loop single-control (OLSC) and open-loop multiple-control (OLMC). Next, we implement the stochastic in expectation UCCD (SE-UCCD) and worst-case robust UCCD (WCR-UCCD) for a simplified strain-actuated solar array (SASA) case study. For the implementation of SE-UCCD, we use generalized Polynomial Chaos expansion and benchmark the results against Monte Carlo Simulation. Next, we solve a simple SASA WCR-UCCD through OLSC and OLMC structures. Insights from such implementations indicate that constructing, implementing, and solving a UCCD problem requires an in-depth understanding of the problem at hand, formulations, and solution strategies to best address the underlying co-design under uncertainty questions.
Development of a Novel 3-Universal-Spherical-Revolote Soft Parallel Robot
Authors: Abidoye Cecil , Grace Devin , Contreras-Esquen Andrea , Edwards Aden , Ashuri Turaj , Tekes Ayse , Amiri Moghadam Amir Ali
Published: February 2023

Soft parallel robots are among the latest advancements in the field of soft robotics with wide range of applications. Most of the existing soft robotic systems comprise from serial soft arms which can provide high degrees of freedom (DOF), but suffer from low stiffness, and limited payload due to their soft structure. To address these issues recently researchers have introduced soft parallel robots. Similar to their rigid counterparts, soft parallel robot will have higher blocking force, stiffness, and accuracy. We have previously introduced two, and three DOF soft parallel robots and in the current work we will introduce a novel six DOF robot named 3-universal-spherical-revolute (3USR) soft parallel robot. This robotic system is consisted of three closed-loop kinematic chains. Each chain includes a soft active arm with two DOF which is connected to a compliant passive link through soft joints. This configuration provides six DOF for the soft robot (x, y, z, roll, pitch, yaw). The prototype of the robot is 3D printed using NINJA flex, thermoplastic polyurethane (TPU), and polylactic acid (PLA). Each soft active arm consists of a two DOF tendon driven soft actuator which is 3D printed using NINJA flex and are actuated using two servo motors. Two types of soft joints are used namely soft spherical and revolute joints. The shape and size of the soft joints are optimized so that the robot will achieve six DOF. MATLAB Simscape model is used to simulate the dynamical response of the mechanism for various inputs.