bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of the informed health choices secondary school intervention on the ability of students in Kenya to think critically about health choices: A cluster‐randomized trial
Authors: Chesire Faith , Kaseje Margaret , Ochieng Marlyn , Ngatia Benson , Mugisha Michael , Ssenyonga Ronald , Oxman Matt , Nsangi Allen , Semakula Daniel , Rose Christopher James , Nyirazinyoye Laetitia , Dahlgren Astrid , Lewin Simon , Sewankambo Nelson K , Rosenbaum Sarah , Oxman Andrew D
Published: September 2023

Aim

There is an overabundance of claims about the advantages and disadvantages of health interventions. People need to be able to appraise the reliability of these claims. The aim of this two‐arm cluster‐randomized trial was to evaluate the Informed Health Choices secondary school intervention designed to teach students to assess claims about the effects of health actions and make informed decisions.

Methods

We conducted the trial among students from 80 secondary schools in five subcounties in Kenya. We used stratified randomization to allocate schools to the intervention or control arm. The intervention included a 2‐day teacher training workshop and 10 lessons that addressed nine prioritized key concepts for assessing claims about treatment effects. We did not intervene in the control schools. The primary outcome was the proportion of students with a passing score (≥ 9/18 correct answers) on the Critical Thinking about Health test, which included two multiple‐choice questions for each concept.

Results

Between May 11, 2022, and July 8, 2022, we recruited 3362 students and 80 teachers. We allocated 1863 students and 40 teachers to the intervention and 1499 students and 40 teachers to the control arm. In the intervention schools, 1149/1863 (61.7%) of students achieved a passing score compared to 511/1499 (34.1%) in the control schools (odds ratio 3.6 (95% CI 2.5–5.2),p < 0.0001).

Conclusions

The intervention had a large effect on students’ ability to think critically about health interventions. It is possible to integrate the learning of critical thinking about health within Kenya secondary school curriculum.
Quadriceps muscle contraction causes medial patellofemoral ligament elongation by intermeshed fibers of vastus medialis oblique muscle
Authors: Mostowy Marcin , Puzio Tomasz , Matera Katarzyna , Kozieł Michał , Stanek Jakub , Bawor Michalina , Grzelak Piotr , Domżalski Marcin E.
Published: September 2023

The first aim of this study was to compare the medial patellofemoral length between contracted and relaxed quadriceps muscle and second to assess the importance of the intermeshed vastus medialis oblique fibers. After a priori power analysis (α = 0.05, power [1−β] = 0.95), 35 healthy males aged 18–30 were prospectively examined with a 3.0‐T magnetic resonance imaging (MRI) scanner in 10–15° of knee flexion. Two axial MRI sequences (25 s each) were made with relaxed and contracted quadriceps. Two blinded, independent raters measured twice medial patellofemoral ligament length (curved line) and attachment‐to‐attachment length (straight line). Mean medial patellofemoral ligament length and attachment‐to‐attachment length with relaxed quadriceps was: 65.5 mm (SD = 3.7), 59.7 mm (SD = 3.6), and after contraction, it increased to 68.7 mm (SD = 5.3), 61.2 mm (SD = 4.7); p < 0.01 and <0.001, respectively. Intraclass correlation coefficients for intra‐ and inter‐rater reliabilities ranged from 0.55 (moderate) to 0.97 (excellent). Mean medial patellofemoral ligament length elongation after quadriceps contraction was significantly greater (3.2 mm, SD = 3.9) than mean attachment‐to‐attachment length elongation (1.6 mm, SD = 2.8); p < 0.001. Contraction of quadriceps muscle causes elongation of the medial patellofemoral ligament to the extent greater than the elongation of distance between its attachments. This confirms that medial patellofemoral ligament elongation after quadriceps contraction results not only from movement of its patellar attachment but also directly from intermeshed vastus medialis oblique fibers pulling medial patellofemoral ligament in a different direction creating a bow‐like construct in agreement with the “pull‐and‐guide mechanism” proposed in the literature.
Efficacy and safety of laser‐related therapy for melasma: A systematic review and network meta‐analysis
Authors: Ma Wenyi , Gao Qian , Liu Jinghua , Zhong Xiaojing , Xu Tongtong , Wu Qinyao , Cheng Zilin , Luo Nana , Hao Pingsheng
Published: September 2023

Background

Melasma is a prevalent, persistent hyperpigmentation disorder that negatively affects the psychological health of patients. However, the treatment outcome remains unsatisfactory due to the complexity of pathogenesis, recurrence characteristics, and relatively high morbidity.

Objectives

To compare the performance of laser‐related therapies in improving the melasma area severity index (MASI) score of melasma and the occurrence of adverse effects by network meta‐analysis (NMA).

Methods

From the inception to November 2022, eligible randomized controlled trials were identified. Two investigators independently searched relevant studies from PUBMED, EMBASE, and the Cochrane Library database.

Results

A total of 39 clinical studies with 1394 participants were eligible for enrollment. For efficacy, the NMA demonstrated that Q‐switched Nd: YAG laser + topical medications (QSND+TM) was superior to Q‐switched Nd:YAG laser (QSND) [MD = −4.21 (−6.80, −1.63)], Er: YAG laser + topical medications (ERYL+TM) [MD = ‐3.52 (−6.84, −0.19)], and picosecond laser + topical medications (PICO+TM) [MD = −4.80 (−9.33, −0.27)]. The microneedling + topical medications (MN+TM) was superior to picosecond laser (PICO) [MD = −5.26 (−10.44, −0.08)] and topical medications (TM) [MD = −5.22 (−9.20, −1.23)]. The top five of the surface under the cumulative ranking curve value (SUCRA) are Q‐switched Nd:YAG laser + topical medications (QSND+TM 85.9%), oral tranexamic acid (oTA 80.1%), microneedling + topical medications (MN+TM 79.7%), Q‐switched Nd:YAG laser + intense pulse light (QSND+IPL 78.9%), and fractional carbon dioxide laser + topical medications (FCDL+TM 70.5%).

Conclusions

In conclusion, the Qs‐Nd:YAG laser with topical medications is the first choice for treating melasma according to the SUCRA value. Among the three treatment modalities, namely MN + TM, PICO, and TM, our recommendation favors MN+TM as the superior choice for enhancing the curative efficacy in melasma. However, the actual clinical choice should also take into account the adverse effects, the skin type of the patient, the duration of the disease, and other relevant factors.
BRCA1 expression, its correlation with clinicopathological features, and response to neoadjuvant chemotherapy in high‐grade serous ovarian cancer
Authors: Patil Akkamahadevi , Patil Sharada , Anupama C. E. , Rajarajan Savitha , Nimbalkar Vidya P. , Amirtham Usha , Champaka G. , Suma M. N. , Patil Geetha V. , Nargund Ashwini , Pallavi V. R. , Jacob Linu , Premalatha C. S. , Prabhu Jyothi S.
Published: September 2023

Aim

In high‐grade serous ovarian cancers (HG‐SOC), BRCA1 mutation is one of the predominant mutations reported by various studies. However, the non‐mutational mechanisms of BRCA pathway inactivation in HG‐SOC are unclear. We evaluated BRCA1 inactivation by estimating its expression with its repressor, ID4, in primary and neoadjuvant chemotherapy (NACT)‐treated HG‐SOC tumors with known therapeutic responses.

Methods

We evaluated the expression pattern of BRCA1 protein by immunohistochemistry in 119 cases of HG‐SOC from a hospital cohort consisting of primary (N = 69) and NACT‐treated (N = 50) tumors. Histological patterns (SET), stromal infiltration by lymphocytes (sTILs), and chemotherapy response score (CRS) were estimated by microscopic examination. Gene expression levels of BRCA1, and its repressor ID4, were estimated by qPCR. The association of BRCA1 protein and mRNA with clinicopathological features was studied. The relevance of the BRCA1/ID4 ratio was evaluated in tumors with different CRS.

Results

BRCA1 protein expression was observed in 12% of primary and 19% of NACT‐treated HG‐SOC tumors. We observed moderate concordance between BRCA1 protein and mRNA expression (AUC = 0.677). High BRCA1 mRNA expression was significantly associated with a more frequent SET pattern (p = 0.024), higher sTILs density (p = 0.042), and increased mitosis (p = 0.028). BRCA1‐negative tumors showed higher expression of ID4 though not statistically significant. A higher BRCA1/ID4 ratio was associated with high sTILs density in primary (p = 0.042) and NACT‐treated tumors (p = 0.040).

Conclusion

Our findings show the utility of the BRCA1/ID4 ratio in predicting neoadjuvant therapy response, which needs further evaluation in larger cohorts with long‐term outcomes.
Remembrances of Lauren B. Edelman both personal and professional
Authors: Stryker Robin
Published: September 2023

Well, that's a fine pickle! I really want to write this essay to honor Lauren B. Edelman (Laurie to me and many others). But, I alsodon'twant to write it because writing it means acknowledging that Laurie has died—way, WAY too early. I haven't really wanted to acknowledge this incredibly distressing reality. I shall miss Laurie in perpetuity as one of my closest intellectual interlocutors and colleagues and also as one of my dearest friends.
Learning from Laurie Edelman
Authors: Albiston Catherine R. , Obasogie Osagie K. , Morrill Calvin
Published: September 2023

Faculty members, students, policymakers, practitioners, and laypersons will learn from Laurie Edelman's brilliant scholarship for generations to come. She developed not only a new theory and a conceptual vocabulary for understanding the interplay of law and organizations—think, “legal endogeneity,” “managerialization of law,” or “symbolic structures” (Edelman, 2016)—but also a more precise account of the mutual influence between law and society. In this essay, we hold her scholarly contributions aside for a moment to explore what the three of us learned from Laurie in two of her most cherished professional roles as mentor and research collaborator. In many ways, she seemed happiest in these roles, whether advising students and early-career faculty (especially those most likely to be marginalized in academic circles, such as persons identifying as women and/or LGBTQ+, persons of color, persons with disabilities, or first-generation scholars) or working with scholars of diverse expertise and statuses on large, empirical projects.
Petrogenesis of Chang'E‐5 young mare low‐Ti basalts
Authors: Li Linxi , Hui Hejiu , Hu Sen , Wang Hao , Yang Wei , Chen Yi , Wu Shitou , Gu Lixin , Jia Lihui , Wu Fuyuan
Published: September 2023

The regolith samples returned by the Chang'E‐5 mission (CE‐5) contain the youngest radiometrically dated mare basaltic clasts, which provide an opportunity to elucidate the magmatic activities on the Moon during the late Eratosthenian. In this study, detailed petrographic observations and comprehensive geochemical analyses were performed on the CE‐5 basaltic clasts. The major element concentrations in individual plagioclase grain of the CE‐5 basalts may vary slightly from core to rim, whereas pyroxene has clear chemical zonation. The crystallization sequence of the CE‐5 mare basalts was determined using petrographic and geochemical relations in the basaltic clasts. In addition, both fractional crystallization (FC) and assimilation and fractional crystallization models were applied to simulate the chemical evolution of melt equilibrated with plagioclase in CE‐5 basalts. Our results reveal that the melt had a TiO2 content of ~3 wt% and an Mg# of ~45 at the onset of plagioclase crystallization, suggesting a low‐Ti parental melt of the CE‐5 basalts. The relatively high FeO content (>14.5 wt%) in melt equilibrated with plagioclase could have resulted in extensive crystallization of ilmenite, unlike in Apollo low‐Ti basalts. Furthermore, our calculations showed that the geochemical evolution of CE‐5 basaltic melt could not have occurred in a closed system. On the contrary, the CE‐5 basalts could have assimilated mineral, rock, and glass fragments that have higher concentrations of KREEP elements (potassium, rare earth elements, and phosphorus) in the regolith during magma flow on the Moon's surface. The presence of the KREEP signature in the CE‐5 basalts is consistent with literature remote sensing data obtained from the CE‐5 landing site. These KREEP‐bearing fragments could originate from KREEP basaltic melts that may have been emplaced at the landing site earlier than the CE‐5 basalts.
Characterization of the Arn lipopolysaccharide modification system essential for zeamine resistance unveils its new roles in Dickeya oryzae physiology and virulence
Authors: Liang Zhibin , Huang Luhao , Liu Huidi , Zheng Ying , Feng Jiani , Shi Zurong , Chen Yufan , Lv Mingfa , Zhou Jianuan , Zhang Lian‐Hui , Chen Shaohua
Published: September 2023

The zeamines produced by Dickeya oryzae are potent polyamine antibiotics and phytotoxins that are essential for bacterial virulence. We recently showed that the RND efflux pump DesABC in D. oryzae confers partial resistance to zeamines. To fully elucidate the bacterial self‐protection mechanisms, in this study we used transposon mutagenesis to identify the genes encoding proteins involved in zeamine resistance in D. oryzae EC1. This led to the identification of a seven‐gene operon, arnEC1, that encodes enzyme homologues associated with lipopolysaccharide modification. Deletion of the arnEC1 genes in strain EC1 compromised its zeamine resistance 8‐ to 16‐fold. Further deletion of the des gene in the arnEC1 mutant background reduced zeamine resistance to a level similar to that of the zeamine‐sensitive Escherichia coli DH5α. Intriguingly, the arnEC1 mutants showed varied bacterial virulence on rice, potato, and Chinese cabbage. Further analyses demonstrated that ArnBCATEC1 are involved in maintenance of the bacterial nonmucoid morphotype by repressing the expression of capsular polysaccharide genes and that ArnBEC1 is a bacterial virulence determinant, influencing transcriptional expression of over 650 genes and playing a key role in modulating bacterial motility and virulence. Taken together, these findings decipher a novel zeamine resistance mechanism in D. oryzae and document new roles of the Arn enzymes in modulation of bacterial physiology and virulence.
The potential of arbuscular mycorrhizal fungi to enhance metallic micronutrient uptake and mitigate food contamination in agriculture: prospects and challenges
Authors: Moreno Jiménez Eduardo , Ferrol Nuria , Corradi Nicolas , Peñalosa Jesús M. , Rillig Matthias C.
Published: September 2023

Optimizing agroecosystems and crops for micronutrient uptake while reducing issues with inorganic contaminants (metal(loid)s) is a challenging task. One promising approach is to use arbuscular mycorrhizal fungi (AMF) and investigate the physiological, molecular and epigenetic changes that occur in their presence and that lead to changes in plant metal(loid) concentration (biofortification of micronutrients or mitigation of contaminants). Moreover, it is important to understand these mechanisms in the context of the soil microbiome, particularly those interactions of AMF with other soil microbes that can further shape crop nutrition. To address these challenges, a two‐pronged approach is recommended: exploring molecular mechanisms and investigating microbiome management and engineering. Combining both approaches can lead to benefits in human health by balancing nutrition and contamination caused by metal(loid)s in the agro‐ecosystem.
A look‐back from the future: Anthropogenic crisis and memory in N. K. Jemisin's Broken Earth trilogy
Authors: Borowska‐Szerszun Sylwia
Published: September 2023

Referring to recent discussions on the challenges the concept of the Anthropocene poses for humanities and literary representation, this article investigates N. K. Jemisin's Broken Earth trilogy as a narrative that addresses the crisis of imagination, in particular with respect to memory. Examining the tensions between individual, collective, and planetary memory, I read Jemisin's novels as an attempt to direct attention to the systemic exploitation of both marginalized minorities and the environment as a key ethical problem of the Anthropocene, which necessitates rethinking the relationship between humanity, climate change, and the planet in the face of the forthcoming crisis.
In or out? Citizenship outcomes of working sexual and gender minority people of Canada
Authors: Dilmaghani Maryam , Dias Jeremy
Published: September 2023

Despite the greater visibility of sexual and gender minorities, due to data limitations, the quantitative literature on their citizenship outcomes is very limited. Using a large original survey of Canadian sexual and gender minorities and the Canadian General Social Survey, this article first examines the extent of political inclusion of sexual and gender minorities, as measured by sense of belonging to Canada and the province of residence, likelihood of voting, and confidence in the police and the justice system. Sexual and gender minorities are generally found to have a markedly weaker sense of belonging to Canada and confidence in its institutions. Next, these patterns are re‐examined accounting for the degree of outness. The results indicate considerable discrepancies across sexual and gender minorities in how outness affects their citizenship outcomes. In particular, it seems that the sociopolitical profile of these groups plays an important mediating role in the effects of outness on their citizenship outcomes.

Related Articles

Burnett, Craig M., and Aaron S. King. 2015. “The Personal Politics of Same‐Sex Marriage.” Politics & Policy 43(4): 586–610. https://doi.org/10.1111/polp.12126.

Lewis, Gregory B., Marc A. Rogers, and Kenneth Sherrill. 2011. “Lesbian, Gay, and Bisexual Voters in the 2000 US Presidential Election.” Politics & Policy 39(5): 655–77. https://doi.org/10.1111/j.1747‐1346.2011.00315.x.

Winburn, Jonathan, and Amanda Winburn. 2020. “The Role of Political Ideology in Public Opinion toward Enumerated Antibullying Policies in Public Schools.” Politics & Policy 48(3): 442–63. https://doi.org/10.1111/polp.12355.
Applied biostatistics in clinical trials for 15‐year‐old pupils
Authors: Lora David
Published: September 2023

It is important for young people to be aware of job profiles and activities in the professional world. Bringing the education system closer to the professional world is vital for them to make decisions about their academic and professional futures. Programs developed to connect 15‐year‐old students who in Spain are in year 4 of their Compulsory Secondary Education, and Research Support Units within the Health Research Institutes of the Hospitals and the Clinical Research Support Platforms of the Carlos III Institute of Health are a good opportunity to highlight the role of biostatistics in clinical trials. The aim of this article is to share the outcomes of and learnings from an interactive workshop for 15‐year‐old students on biostatistics and clinical trials conducted within the 4°ESO + Empresa program and directed by the Scientific Support Unit of the Health Research Institute of Hospital 12 de Octubre in Madrid, Spain.
Functional allele of a MATE gene selected during domestication modulates seed color in chickpea
Authors: Thakro Virevol , Varshney Nidhi , Malik Naveen , Daware Anurag , Srivastava Rishi , Mohanty Jitendra K. , Basu Udita , Narnoliya Laxmi , Jha Uday Chand , Tripathi Shailesh , Tyagi Akhilesh K. , Parida Swarup K.
Published: September 2023

Seed color is one of the key target traits of domestication and artificial selection in chickpeas due to its implications on consumer preference and market value. The complex seed color trait has been well dissected in several crop species; however, the genetic mechanism underlying seed color variation in chickpea remains poorly understood. Here, we employed an integrated genomics strategy involving QTL mapping, high‐density mapping, map‐based cloning, association analysis, and molecular haplotyping in an inter‐specific RIL mapping population, association panel, wild accessions, and introgression lines (ILs) of Cicer gene pool. This delineated a MATE gene, CaMATE23, encoding a Transparent Testa (TT) and its natural allele (8‐bp insertion) and haplotype underlying a major QTL governing seed color on chickpea chromosome 4. Signatures of selective sweep and a strong purifying selection reflected that CaMATE23, especially its 8‐bp insertion natural allelic variant, underwent selection during chickpea domestication. Functional investigations revealed that the 8‐bp insertion containing the third cis‐regulatory RY‐motif element in the CaMATE23 promoter is critical for enhanced binding of CaFUSCA3 transcription factor, a key regulator of seed development and flavonoid biosynthesis, thereby affecting CaMATE23 expression and proanthocyanidin (PA) accumulation in the seed coat to impart varied seed color in chickpea. Consequently, overexpression of CaMATE23 in Arabidopsis tt12 mutant partially restored the seed color phenotype to brown pigmentation, ascertaining its functional role in PA accumulation in the seed coat. These findings shed new light on the seed color regulation and evolutionary history, and highlight the transcriptional regulation of CaMATE23 by CaFUSCA3 in modulating seed color in chickpea. The functionally relevant InDel variation, natural allele, and haplotype from CaMATE23 are vital for translational genomic research, including marker‐assisted breeding, for developing chickpea cultivars with desirable seed color that appeal to consumers and meet global market demand.
Consequences of group III/IV afferent feedback and respiratory muscle work on exercise tolerance in heart failure with reduced ejection fraction
Authors: Smith Joshua R. , Senefeld Jonathon W. , Larson Kathryn F. , Joyner Michael J.
Published: September 2023

Exercise intolerance and exertional dyspnoea are the cardinal symptoms of heart failure with reduced ejection fraction (HFrEF). In HFrEF, abnormal autonomic and cardiopulmonary responses arising from locomotor muscle group III/IV afferent feedback is one of the primary mechanisms contributing to exercise intolerance. HFrEF patients also have pulmonary system and respiratory muscle abnormalities that impair exercise tolerance. Thus, the primary impetus for this review was to describe the mechanistic consequences of locomotor muscle group III/IV afferent feedback and respiratory muscle work in HFrEF. To address this, we first discuss the abnormal autonomic and cardiopulmonary responses mediated by locomotor muscle afferent feedback in HFrEF. Next, we outline how respiratory muscle work impairs exercise tolerance in HFrEF through its effects on locomotor muscle O2 delivery. We then discuss the direct and indirect evidence supporting an interaction between locomotor muscle group III/IV afferent feedback and respiratory muscle work during exercise in HFrEF. Last, we outline future research directions related to locomotor and respiratory muscle abnormalities to progress the field forward in understanding the pathophysiology of exercise intolerance in HFrEF.
Rate-Limited and Energy-Efficient Feedforward Control for Multi-Fuel Unmanned Aircraft Systems Engine
Authors: Govind Raju Sathya Aswath , Cornelius Andrew , Sun Zongxuan , Kim Kenneth , Kweon Chol-Bum Mike
Published: September 2023

Surrogate-model or data-driven model-based control frameworks are becoming increasingly popular in recent years due to their ease of model development and enhanced computational power, making them suitable for real-time use. However, when it comes to modeling aspects related to time, difficulties arise as many of the models deal with quasi-static systems. In this paper, we propose a method to model time-dependent actuator constraints in a surrogate-model-based control framework for controlling the combustion phasing in a multi-fuel UAS engine. Along with this, a conducive method for designing an energy-efficient ignition assistant control is discussed. The developed methods are then tested on a diesel engine, and the results show a more robust and energy-efficient combustion phasing control as the fuel property varies in real-time.
Safe Operating Limits of Vehicle Dynamics Under Parameter Uncertainty Using Koopman Spectrum
Authors: Kumar Alok , Umathe Bhagyashree , Vaidya Umesh , Kelkar Atul
Published: September 2023

Ground vehicles operate under different driving conditions, which require the analysis of varying parameter values. It is essential to ensure the vehicle’s safe operation under all these conditions of the parameter variation. In this paper, we investigate the safe operating limits of a ground vehicle by performing the reachability analysis for varying parameters using the Koopman spectrum approach. The reachable set is computed using the Koopman principal eigenfunctions obtained from a convex optimization formulation for different values of the parameter. We consider the two degrees-of-freedom nonlinear quarter-car model to simulate the vehicle’s dynamics. Based on the obtained reachable sets, we provide the mean and variance computation framework with parametric uncertainty. The results show that the reachable set for each value provides valuable information regarding the safe operating limits of the vehicle and can assist in developing safe driving strategies.
A Recursive System Identification With Non-Uniform Temporal Feedback Under Coprime Collaborative Sensing
Authors: Ouyang Jinhua , Chen Xu
Published: September 2023

We present a system identification method based on recursive least-squares (RLS) and coprime collaborative sensing, which can recover system dynamics from non-uniform temporal data. Focusing on systems with fast input sampling and slow output sampling, we use a polynomial transformation to reparameterize the system model and create an auxiliary model that can be identified from the non-uniform data. We show the identifiability of the auxiliary model using a Diophantine equation approach. Numerical examples demonstrate successful system reconstruction and the ability to capture fast system response with limited temporal feedback.
Computational Fluid Dynamics Modeling Analysis of a Martian Rotorcraft With Individual Blade Control
Authors: Schulman Paul , Berndt Samuel-Hunter , Roman Christiahn , Tan Xiaobo
Published: September 2023

Computational fluid dynamics (CFD) analysis was conducted on a proposed blade root-actuated individual blade control (IBC) system for future Martian rotorcraft. IBC offers many potential benefits to rotary-winged exploration of Mars, including precision control of rotor blade forces. This study seeks to provide an estimate of rotor blade force and system power as a basis for concept feasibility analysis and experimental prototyping. ansys fluent was used to compute blade pitching moment, lift, and drag under various feathering waveforms, amplitudes, biases, and frequencies. It is determined that the rapid feathering characteristic of IBC has a non-negligible impact on blade forces. It is also found that actuators with power ratings on the order of 101 W are likely sufficient for blade actuation on Martian rotorcraft.
Lattice Boltzmann Simulations of Non-Homogeneous Li–O2 Battery Cathode: The Effect of Spatial and Temporal Porosity Variations
Authors: Mohan T. Ajeesh , Jithin M. , Das Malay K.
Published: September 2023

The porosity of the cathode in a lithium–oxygen battery is a crucial parameter that influences oxygen transport and active surface area availability. This study explores various cathode models with different initial porosity distributions and analyzes the porosity evolution during discharge. The objective is to maximize the active surface area utilization of the cathode and increase the battery’s discharge capacity. The simulations employ a recently developed lattice Boltzmann method (LBM) model proposed by Chen et al. (2017, “Simulation of Double Diffusive Convection in Fluid-Saturated Porous Media by Lattice Boltzmann Method,” Int. J. Heat Mass Transfer, 108, pp. 1501–1510), which is capable of handling spatial and temporal variations in diffusion coefficient values. The results demonstrate that a hierarchical porous cathode provides a better specific capacity than a uniform porous cathode with the same average initial porosity. The specific capacity increases as the magnitude of initial porosity variation in the domain increases. Furthermore, incorporating oxygen channels improves oxygen transport in the cathode and offers a better specific capacity than the hierarchical porous cathode. A combination of hierarchical porous media and oxygen channels delivers the best specific capacity among all the other cathode models, as it efficiently balances oxygen transport and active surface area.
Mechanical and Economic Analysis of Conventional Aluminum Photovoltaic Module Frames, Frames With Side Holes, and Open-Source Downward-Fastened Frames for Non-Traditional Racking
Authors: Sadat Seyyed Ali , Vandewetering Nicholas , Pearce Joshua M.
Published: September 2023

Using bolts through the back of a solar photovoltaic (PV) module frames to attach them to racking is time consuming and awkward, so commercial PV installations use clamping technologies on the front. Conventional and proprietary clamps are costly and demand access to supply chains for uncommon mechanical components that limit deployment velocity. To overcome these challenges, this study presents new open-source downward-fastened and side-fastened aluminum (Al) framing designs, which are easy to install and compatible with metal and wood racks. The proposed parametric open-source designs are analyzed through finite element method (FEM) simulations and economic analysis is performed to compare to conventional PV frame at both the module and system levels. The FEM results showed all the frames have acceptable mechanical reliability and stability to pass IEC 61215 standards. The results show the new frame (with a bottom width of 29 mm and thickness of 1.5 mm) has about a 2% land use efficiency penalty, but has better mechanical stability (lower stress and deflections), is easier to install, and has reduced material economic costs compared to conventional frames. The results are promising for the use of the new PV frame designs for distributed manufacturing targeted at specific applications.
Digital Twin for Autonomous Surface Vessels to Generate Situational Awareness
Authors: Menges Daniel , Sætre Simon Mork , Rasheed Adil
Published: September 2023

Multiple studies show that humans are the leading cause of maritime accidents. Therefore, the interest in introducing autonomous surface vessels, particularly in the commercial sector, is receiving increasing attention. Digital twins, virtual representations of physics assets or processes enabled through data and models for real-time control, optimization, monitoring, and informed decision-making, are seen as key enablers for autonomy. Based on their capability, a digital twin is generally categorized on a scale from 0–5 (0-standalone, 1-descriptive, 2-diagnostic, 3-predictive, 4-prescriptive, 5-autonomous). The current work aims at concretizing the categorization in the context of autonomous vessels. It demonstrates some capability levels by introducing the development of an extendable digital twin framework created in the Unity game engine using physics-based models and real-time data. For this purpose, real-time weather and automatic identification system (AIS) data is streamed. While computer-aided design (CAD) and a three-dimensional (3D) height map build the foundation of a standalone digital twin, real-time data, physics-based models, and synthetic sensors set the basis of descriptive representations. Finally, an environmental disturbance observer enables the first diagnostic abilities, while a reinforcement learning algorithm pushes towards autonomous capabilities. It is argued that the work will improve the overall situational awareness for safe sea operations.
Estimation of Viscous Damping Force and Nonlinear Wave Force Acting on a Floating Offshore Wind Turbine Using Computational Fluid Dynamics (CFD)
Authors: Yoshimoto Haruki , Amaya Ichiro , Kamizawa Ken , Nishimura Shunsuke , Sato Norikazu
Published: September 2023

Japan Marine United Corporation (JMU) are currently developing substructures for floating offshore wind turbines (FOWT). The structure of the FOWT substructure must have sufficient strength against all environmental external forces during the mooring lifetime. Accurately estimating environmental external forces is therefore a very important factor in reducing project uncertainty.

Environmental forces acting on FOWT can be separated into components such as waves, winds, and tidal currents, and wave loads are often the dominant environmental forces acting on substructures. The wave loading on the FOWT can be divided into a linear component that is proportional to wave height and a nonlinear component that is not proportional to wave height. It is well known that the linear component can be estimated with high accuracy, and the estimation method is well established. However, the nonlinear component often depends on the individual shape of the floating body, and special consideration needs to be given to each floating body. Among the nonlinear phenomena related to waves, the influence of viscous damping force is particularly famous, and it is known that it has a great influence on the dynamic response of floating bodies in waves.

In this paper, we focus on estimating the viscous damping force acting on the floating body by using computational fluid dynamics (CFD) and clarifying its accuracy by comparing with the results of the tank test. In addition, by comparing the dynamic wave pressure acting on the floating body by both CFD and potential theory, the influence of nonlinearity in wave loading is evaluated. The floating body is assumed to be a cross-shaped semi-sub type floating body that JMU is developing, and CFD assumes multiple cases such as free decay and regular waves. The tank test refers to the results of the 1/64 scale test conducted in JMU’s own tank.
LIDAR-Assisted Feedforward Pitch Control of 15 MW Floating Offshore Wind Turbines
Authors: Russell Andrew , Collu Maurizio , McDonald Alasdair , Thies Philipp , Mortimer Alan , Quayle Alexander
Published: September 2023

Nacelle-mounted, forward-facing Light Detection and Ranging (LIDAR) technology is able to measure the wind field as it approaches a wind turbine. Knowledge of the incoming wind can be used for feedforward turbine control, enabling torque, pitch or yaw systems in advance of the wind’s impact. This can enhance turbine performance through improved rotor speed regulation and power capture, while reducing structural loads. LIDAR has previously exhibited its most significant benefits for turbine performance when assisting with blade pitch control in above-rated wind speed conditions. The impact of feedforward pitch control implementation in floating offshore wind turbines is expected to vary for different substructures due to their differing natural frequencies of motion and rates of feedback pitch control actuation, as a consequence of modified controller gains required to overcome negative damping. This computational study outlines the LIDAR-assisted feedforward pitch control implementation approach, and compares its impacts on two floating substructures supporting the IEA 15 MW reference turbine: the UMaine VolturnUS-S Semi-Submersible and the WindCrete Spar. Under turbulent wind conditions and by using a LIDAR simulator to capture the incoming wind field, both floating turbine configurations benefitted from LIDAR-assisted feedforward pitch control, through improved rotor speed regulation by up to 33%, reduced loads by up to 17% and platform motions by up to 19%. These performance improvements can lead to reduced component failure rates, maintenance, and, ultimately, reduced lifetime operations and maintenance expenditure.
Using CFD to Assess the Wind Loads on the Topside of a Self-Propelled Wind Turbine Installation Jack-Up – A Comparative Study of Simplified With Detailed Topside Structures at Model-Scale and Full-Scale
Authors: Sulaiman Zana
Published: September 2023

This paper presents the results of wind loads computational fluid dynamics (CFD) calculations performed on the topside structures of a typical GustoMSC designed self-propelled wind turbine installation jack-up. To investigate the effect of geometrical simplifications on the overall wind loads acting on the jack-up, the CFD calculations were performed for the detailed as well as simplified topside structures. An atmospheric boundary layer profile was applied. The full range of heading angles was considered. The CFD results were validated through comparison with the wind tunnel tests which were carried out at the German-Dutch wind tunnels (DNW) in Marknesse, The Netherlands. Moreover, a comparison is presented between the simplified and detailed topside structures at model-scale as well as at full-scale. Based on the results of the CFD calculations at model-scale and full-scale, this paper discusses the scale effects of the wind loads acting on a self-propelled wind turbine installation jack-up. Furthermore, the effects of topside simplifications on the wind loads and advantages of the applied approach are highlighted.
Experimental Quantification of Collapse Enhancement From Light Thermal Treatment
Authors: Timms Chris , DeGeer Duane , Chandler Bruce , Liu Ping , Swanek Doug , Chen Qishi
Published: September 2023

Over thirty years ago, as conventional oil and gas prospects began migrating into ultra-deepwater, new engineering, construction, and installation challenges arose, demanding robust solutions to ensure reliable project delivery. Many of these deepwater developments required large-diameter export pipelines, or long-distance transmission lines, with sufficient wall thickness to resist unprecedentedly high external pressures. Pipeline design standards at the time had little or no history of successful ultra-deepwater pipeline design, and questions were raised as to the adequacy of the collapse equations (and lack of supporting collapse test results) for such water depths, as well as the manufacturing limitations associated with the UOE and JCOE linepipe required for these large-diameter pipelines. Innovative solutions were needed.

In the 1990s, C-FER Technologies (1999) Inc. (“C-FER”) and Intecsea Inc. (“Intecsea”) pioneered the development of design methodologies aimed at optimizing pipeline wall thickness design and incorporating collapse enhancement techniques into the successful delivery of ultra-deepwater pipeline projects around the world. Quantifying the strength recovery gained from a light thermal treatment (LTT) process, such as that obtained from a fusion bonded epoxy (FBE) or three-layer coating process, has been the focal point of these techniques. The methods developed at the time have produced, time and again on various projects, highly reliable wall thickness designs, and leading pipeline-design standards have permitted such methods, establishing their acceptance in pipeline wall thickness design.

This paper presents a summary of some of the leading engineering work achieved over approximately thirty years and some of the projects that have implemented these innovative design techniques, including the challenging tests successfully performed, the design results achieved, and the benefits realized.
Surface Corrosion Fatigue Crack Growth Test in Accelerating Environment Where General Surface Corrosion Proceed in Parallel
Authors: Hayashibara Hitoshi , Fueki Ryutaro , Yamamoto Norio , Sugimoto Tomohiro , Ando Takahiro , Tsumura Shuichi , Anai Yosuke , Murakami Chikahisa , Niwa Toshio , Iwata Toshiaki , Ishibashi Kinya
Published: September 2023

Corrosion fatigue behavior in dilute sulfuric acid solution was examined with high tensile steel. Crack growth tests were conducted to obtain the parameters in Paris law while specimens with a semi elliptical slit were immersed in solution to evaluate the change of crack size during no cyclic load condition. The immersion test revealed that a simulated crack depth was shortened in the test solution due to the difference of corrosion rate between a slit tip and a surface, meaning crack depth will actually decrease under the specific low stress range (or no cyclic load) condition where the competitive phenomenon become significant. Quantitative parameters from these tests were included in the crack growth analysis to improve the previous calculated results. Surface crack growth behavior was also examined in the same corrosive environment by using the tensile specimen with a semi-elliptical pre crack. Two different loading conditions were employed to evaluate the competitive phenomenon. Some test was carried out in a continuous cyclic loading, others were conducted in a combination of continuous cyclic load and no load (applied stress was maintained as zero). It was observed that the crack growth was suppressed in low stress range and high surface corrosion rate conditions.
Offloading Operability of Near-Shore FLNG With Side-by-Side Moored LNG Carrier in Shallow Water Depth
Authors: Kim Mun Sung , Lim Jae Hwan , Yuck Rae Hyoung , Kim Hyun Joe , Heo Jae Kyung
Published: September 2023

Recently, the FLNG projects have been developed for the LNG production near shore field with shallow water depth. In this field, FLNG is permanently moored by jetty system or special structures such as Yoke mooring for the liquefaction of feed gas by pipeline in land side. Like FLNGs which operated in deep water, ship-to-ship (STS) offloading operation is considered in near shore FLNG for the transfer of LNG cargo to shuttle LNG carrier through marine loading arm (MLA) with side-by-side (SBS) mooring arrangement.

However, unlike FLNGs which operated in deep water depth, near shore FLNG has relatively short length due to the use of electric and accommodation from the land side. Also, the environmental conditions are quite differing in near shore as well as finite water depth. This meaning that the need of the special consideration of near shore FLNG for side-by-side (SBS) mooring arrangement.

In this paper, a numerical motion analysis for the side-by-side moored FLNG and LNG carrier in near shore field is carried out in frequency-domain and time-domain. In order to assess the offloading operability of near shore FLNG during operation, dynamic loads acting on the mooring lines and fenders as well as relative motion are calculated for several SBS mooring arrangements.

Throughout the study, it is found that the important of numerical accuracy of hydrodynamic analysis in shallow water depth and environmental conditions such as wind, wave and current. Also, the offloading operability is affected by the side-by-side mooring arrangement.
Development of Ice-Load Algorithm for Real-Time Feedback During Simulator Training
Authors: Miller Logan P. , Quinton Bruce , Soper Jonathan , Veitch Brian
Published: September 2023

The use of simulator training for ice navigation is becoming increasingly widespread, in part due to the difficulty, risk, and expense of providing training on vessels in ice-covered waters. Simulator training offers the opportunity for comparatively inexpensive and low risk training for novices in ice-covered conditions. For effective ship operation, it is important to use a vessel to its capacity in ice, without exceeding this capacity and causing damage to the structure. To this end, an algorithm was developed that detects ship-ice collisions, calculates the ice-loads on the structure, and provides the operator with feedback in terms of how close the load is to exceeding the safe capacity of the structure. At present, the algorithm is ship specific in that its development uses finite element analysis for a specific ship to assess the ship’s structural response for a given ice thickness, strength, and contact geometry, to determine the maximum energy at which a safe collision can occur. This safe collision energy limit can then be implemented into simulator training to give real-time feedback to participants about the safety of ship-ice collisions as they occur. An experimental campaign to test the effect of the feedback for simulator training, as well as its utility as an aid onboard the bridge of ships, is proposed.
Experimental Investigation of Annular Displacement With Fluids of Different Density
Authors: Lund Bjørnar , Ytrehus Jan David , Taghipour Ali , Saasen Arild
Published: September 2023

High inclination and horizontal well sections are common in modern well construction. In mature areas like the North Sea region, practically all producers or injector wells will have highly deviated sections. Adequate displacement during the cementing operation is important to ensure annular barrier integrity and zonal isolation of wells. Since all wells must be permanently plugged before abandonment, annular barriers should be made with a long-term perspective and not only to minimize construction time and cost. Controlled laboratory environments with various fluid compositions and flow parameters are important to develop, validate and improve models and practices, both for cementing and other fluid displacement operations such as casing cleaning.

In this paper we present results from laboratory experiments in a 10 meters long test section using water-based model fluids at horizontal and highly deviated angles. The wellbore and casing are represented by 6.5” ID and 5” OD transparent pipes, respectively.

Water and viscosified water, respectively, were displaced by a potassium formate brine (1.3–1.4 sg) at low and high flow rates, without and with string rotation and with concentric and partially eccentric inner pipe (casing). The displacement was monitored using conductivity probes and video camera recordings. The results show that the density difference between the displaced and displacing fluid totally dominates the displacement process. Thus, neither inclination, string rotation, eccentricity or wellbore inclination were found to have significant impact on the displacement process.
Cuttings-Bed Erosion in Horizontal Wells: Biopolymers Impact and its Rheological Dependence
Authors: Pedrosa Camilo , Baynabaj Mohsen , Paso Kristofer , Saasen Arild
Published: September 2023

Efficient wellbore cleaning in highly deviated and horizontal wells is a challenge, as there are large areas where the cuttings tend to be deposited. Insufficient wellbore cleaning could cause major operational problems and vastly increase drilling costs.

Effective removal of the deposited cuttings-bed is mainly driven by flow rate, flow rheology and drill-pipe rotation, nevertheless in cases where it’s not possible to have drill-pipe rotation the challenge should be accomplished by tailoring the fluid rheology to achieve turbulent flow within the maximum flow rate possible. As a common practice water-based drilling fluids are formulated with biopolymers as viscosity modifiers, such as xanthan gum and polyanionic cellulose (PAC) to adjust the drilling fluid rheology. The viscosity profile that each of these biopolymers imparts is very different, as xanthan gum produces a shear-thinning effect, the PAC behaves as a Newtonian fluid.

This paper shows how the different flow behavior of the fluids composed of biopolymers can influence the cuttings-bed erosion, in a bench-scale lab setup without drill-pipe movement. The simulated cuttings-bed is a 75cm long deposited sand bed in a horizontal section, in addition, two different types of biopolymer-based fluids with similar viscosities at a specific shear rate range are being used to compare how non-Newtonian fluids and Newtonian fluids interact with the deposited cuttings for cleaning efficiency.