bluuebunny/crossref_metadata_2025 huggingface dataset:
Flame Response of a Lean Premixed Swirl Flame to High Frequency Azimuthal Forcing
Authors: Mangold Tobias O. , Orchini Alessandro , Paschereit Christian Oliver , Moeck Jonas P. , Bohon Myles D.
Published: October 2022

This experimental study explores fundamental qualitative differences of the response of a lean-premixed turbulent swirl flame to azimuthal acoustic excitation in the low- (LF), medium- (MF), and high-frequency (HF) regime. An experimental test rig with a cylindrical combustion chamber is equipped with an array of azimuthally distributed acoustic driver outlets in the burner front plate, allowing for the excitation of the flame with a longitudinal wave, and different azimuthal wave types. Phase-averaged chemiluminescence images show that in the LF regime the flame responds to both longitudinal and azimuthal forcing schemes with hydrodynamically induced intensity fluctuation patterns at relatively small wavelength. Azimuthal forcing generates helical intensity patterns, at the same wavelengths but with lower intensities compared to longitudinal forcing. A fundamentally different flame response is observed in the HF regime: Longitudinal forcing generates only a very weak flame response, and the amplitude of the flame response to azimuthal forcing type depends on the forced azimuthal mode. No hydrodynamic structures are evident anymore, but the flame response now uniformly covers each of the flame sides, indicating a purely acoustic response.
The Road to a Digital Twin for Fan-Blade Off and Thermally Enabled Structural Analyses of Aero Engines
Authors: Keskin Akin , Fox Rob
Published: October 2022

Digital Twin is not a buzz word anymore and started to become reality in many industrial applications. The Digital Twin concept does allow design, analysis, test, manufacturing and service data to be merged more closely together to provide an additional value stream for the industry which can help in better product definition, reduced time-to-market, reduced development cost, understanding of in-service events and predictions of product behaviours based on service data. Over the last decade Rolls-Royce has been working to use high-fidelity simulations models together with test data to create models that can be used more in predictive modes to support expensive physical tests and ultimately replace those with cheaper and more flexible computer models.

The paper is going to discuss the journey taken to utilize a Digital Twin of an aero engine to support safety assessment of fan-blade off events but also how the same concept can be used to create a thermally enabled structural model to assess component movements under changing operating conditions with the aim to optimize design. Both Digital Twin models can be of much use in the design, certification but also services phase to understand behaviour and characteristics of the product and its individual sub-modules. The presented work will focus on the model creation aspect, the emphasis into the required accuracy of each modelling step and the link between test and design data for a more seamlessly integration of multiple disciplines. The paper will include a comparison of simulation and test data and will discuss areas of alignment and misalignment and the conclusion that need to be drawn.

Furthermore the paper will depict areas of research needed to improve simulation capability, the importance of close collaboration between industry, academia and authorities, and the significance in having a cross-functional team with experts from various disciplines to contribute to the model set up, run and post-processing to maximize the insight.
Gas Turbine Secondary Air Systems Modeling
Authors: Kocagul Mustafa , Arıkan A. Cihat , Uyav Omer , Ertas Avni , Bruns James , Jayanthi Aditya
Published: October 2022

Modern gas turbine engine designers are challenged with aggressive power, cycle efficiency and operational life requirements. Those targets are directly related with turbine inlet temperature, material selection and design choices. Increasing turbine inlet temperature, increases cycle efficiency and power output; however, operational life is adversely affected. To optimize these contradicting targets, cooling and sealing design choices must be carefully selected, which is the main responsibility of Secondary Air Systems design engineer.

Altair Flow Simulator© (FS) is an integrated one-dimensional flow, thermal, and combustion modeling software that can be used for conceptual as well as detailed design and analysis for any thermo-fluid system design application.

This paper reviews the FS modeling methods that are commonly used for SAS design. The methods to be reviewed include rotating orifice, rotor-stator cavity, and labyrinth seals. The component modeling results are validated by comparing literature test data, company owned test data, and Computational Fluid Dynamics (CFD) analysis. Discharge coefficients for orifices, swirl ratio for rotating cavities and leakage values for smooth-land labyrinth seals are investigated throughout the paper.
An internal expectation guides
Drosophila
egg-laying decisions
Authors: Vijayan Vikram , Wang Zikun , Chandra Vikram , Chakravorty Arun , Li Rufei , Sarbanes Stephanie L. , Akhlaghpour Hessameddin , Maimon Gaby
Published: October 2022

To better understand how animals make ethologically relevant decisions, we studied egg-laying substrate choice in
Drosophila
. We found that flies dynamically increase or decrease their egg-laying rates while exploring substrates so as to target eggs to the best, recently visited option. Visiting the best option typically yielded inhibition of egg laying on other substrates for many minutes. Our data support a model in which flies compare the current substrate’s value with an internally constructed expectation on the value of available options to regulate the likelihood of laying an egg. We show that dopamine neuron activity is critical for learning and/or expressing this expectation, similar to its role in certain tasks in vertebrates. Integrating sensory experiences over minutes to generate an estimate of the quality of available options allows flies to use a dynamic reference point for judging the current substrate and might be a general way in which decisions are made.
PABPN1 functions as a hub in the assembly of nuclear poly(A) domains that are essential for mouse oocyte development
Authors: Dai Xing-Xing , Pi Shuai-Bo , Zhao Long-Wen , Wu Yun-Wen , Shen Jing-Ling , Zhang Song-Ying , Sha Qian-Qian , Fan Heng-Yu
Published: October 2022

Growing oocytes store a large amount of maternal mRNA to support the subsequent “maternal-zygotic transition” process. At present, it is not clear how the growing oocytes store and process the newly transcribed mRNA under physiological conditions. In this study, we report non–membrane-bound compartments, nuclear poly(A) domains (NPADs), as the hub for newly transcribed mRNA, in developing mouse oocytes. The RNA binding protein PABPN1 promotes the formation of NPAD through its N-terminal disordered domain and RNA-recognized motif by means of liquid phase separation.Pabpn1-null growing oocytes cannot form NPAD normally in vivo and have defects in stability of oocyte growing–related transcripts and formation of long 3′ untranslated region isoform transcripts. Ultimately,Pabpn1fl/fl;Gdf9-Cremice are completely sterile with primary ovarian insufficiency. These results demonstrate that NPAD formed by the phase separation properties of PABPN1-mRNA are the hub of the newly transcribed mRNA and essential for the development of oocytes and female reproduction.
A satellite DNA array barcodes chromosome 7 and regulates totipotency via ZFP819
Authors: Fernandes Liane P. , Enriquez-Gasca Rocio , Gould Poppy A. , Holt James H. , Conde Lucia , Ecco Gabriela , Herrero Javier , Gifford Robert , Trono Didier , Kassiotis George , Rowe Helen M.
Published: October 2022

Mammalian genomes are a battleground for genetic conflict between repetitive elements and KRAB-zinc finger proteins (KZFPs). We asked whether KZFPs can regulate cell fate by using ZFP819, which targets a satellite DNA array, ZP3AR. ZP3AR coats megabase regions of chromosome 7 encompassing genes encoding ZSCAN4, a master transcription factor of totipotency. Depleting ZFP819 in mouse embryonic stem cells (mESCs) causes them to transition to a 2-cell (2C)–like state, whereby the ZP3AR array switches from a poised to an active enhancer state. This is accompanied by a global erosion of heterochromatin roadblocks, which we link to decreased SETDB1 stability. These events result in transcription of active LINE-1 elements and impaired differentiation. In summary, ZFP819 and TRIM28 partner up to close chromatin across
Zscan4
, to promote exit from totipotency. We propose that satellite DNAs may control developmental fate transitions by barcoding and switching off master transcription factor genes.
Unconventional superconductivity in topological Kramers nodal-line semimetals
Authors: Shang Tian , Zhao Jianzhou , Hu Lun-Hui , Ma Junzhang , Gawryluk Dariusz Jakub , Zhu Xiaoyan , Zhang Hui , Zhen Zhixuan , Yu Bocheng , Xu Yang , Zhan Qingfan , Pomjakushina Ekaterina , Shi Ming , Shiroka Toni
Published: October 2022

Crystalline symmetry is a defining factor of the electronic band topology in solids, where many-body interactions often induce a spontaneous breaking of symmetry. Superconductors lacking an inversion center are among the best systems to study such effects or even to achieve topological superconductivity. Here, we demonstrate that
T
RuSi materials (with
T
a transition metal) belong to this class. Their bulk normal states behave as three-dimensional Kramers nodal-line semimetals, characterized by large antisymmetric spin-orbit couplings and by hourglass-like dispersions. Our muon-spin spectroscopy measurements show that certain
T
RuSi compounds spontaneously break the time-reversal symmetry at the superconducting transition, while unexpectedly showing a fully gapped superconductivity. Their unconventional behavior is consistent with a unitary (
s
+
ip
) pairing, reflecting a mixture of spin singlets and spin triplets. By combining an intrinsic time-reversal symmetry-breaking superconductivity with nontrivial electronic bands,
T
RuSi compounds provide an ideal platform for investigating the rich interplay between unconventional superconductivity and the exotic properties of Kramers nodal-line/hourglass fermions.
Unlocking the in situ Li plating dynamics and evolution mediated by diverse metallic substrates in all-solid-state batteries
Authors: Cui Can , Yang Hui , Zeng Cheng , Gui Siwei , Liang Jianing , Xiao Ping , Wang Shuhao , Huang Guxin , Hu Mingtao , Zhai Tianyou , Li Huiqiao
Published: October 2022

The mechanisms of Li deposition behaviors, which overwhelmingly affect battery performances and safety, are far to be understood in solid-state batteries. Here, using in situ micro-nano electrochemical scanning electron microscopy (SEM) manipulation platform, dynamic Li plating behaviors on 10 metallic substrates have been tracked, and the underlying mechanisms for dendrite-free Li plating are elucidated. Distinct Li deposition behaviors on Cu, Ti, Ni, Bi, Cr, In, Ag, Au, Pd, and Al are revealed quantitatively in nucleation densities, growth rates, and anisotropic ratios. For Li alloyable metals, the dynamic Li alloying process before Li growth is visually captured. It is concluded that a good affinity for Li and appropriate lattice compatibility between the substrate and Li are needed to facilitate homogeneous Li plating. Our work not only uncovers the Li plating dynamics, shedding light on the design of solid-state batteries, but also provides a powerful integrated SEM platform for future in-depth investigation of solid-state batteries.
Paleoproterozoic Earth and the transition toward modern tectonic processes: A synopsis
Authors: Corrigan* D. , Van Rooyen D.
Published: October 2022

Many of the hallmarks of modern plate-tectonic processes first occurred in the Paleoproterozoic Era, indicating that the mechanical, thermal, and compositional parameters of Earth’s lithosphere had evolved to approximately modern ranges of values by that time. The core of Laurentia preserves widespread examples of both convergent and divergent tectonic processes in the time span from 2.2 to 1.7 Ga, particularly within the Trans-Hudson composite orogen. Large continental masses or supercontinents previously accreted during the Neoarchean Era began to break up between 2.4 and 2.0 Ga, leading to the deposition of widespread passive-margin sedimentary prisms and locally voluminous emplacement of mafic magma in radiating dike swarms. Further rifting and drifting led to the formation of incipient (e.g., Bravo Formation) to fully developed oceanic crust (e.g., Manikewan Ocean). Plate convergence beginning ca. 1.92 Ga heralded the demise of the Manikewan Ocean ~150 m.y. after its postulated opening. Protracted subduction of oceanic lithosphere over a period of ~90 m.y. produced a series of island arcs, some of which (Lynn Lake, Flin Flon, Snow Lake) host world-class volcanogenic massive sulfide (VMS) ± Au deposits. Plate convergence also led to progressive southeastward (present-day coordinates) accretion of microplates on a pre-amalgamated core consisting of the Slave craton and the Rae and Hearne “Provinces,” forming the Churchill plate. Following the formation of the Churchill plate collage ca. 1.86 Ga, subduction of oceanic lithosphere organized along an ~4000-km-long, north-dipping subduction zone along the southeastern edge of the Churchill plate, producing voluminous continental arc magmas in an Andean-type setting. The final phase of tectonic evolution involved collision of the Superior and North Atlantic cratons with the Churchill plate and intervening juvenile oceanic arc terranes. That phase was strongly influenced by the irregular shape of the indenting Superior craton, favoring the development of oroclines and leading to escape tectonics and lateral extrusion of continental microplates. For the most part, the Trans-Hudson was a hot but not necessarily thick orogen, perhaps reflecting a higher geothermal gradient during the Paleoproterozoic Era.
Changes in the growth of very preterm infants in England 2006–2018
Authors: Young Aneurin , Cole Tim J , Cheng Guo , Ennis Sarah , Beattie R Mark , Johnson Mark John
Published: October 2022

Objective

To compare weight gain from birth to term equivalent age in very preterm infants in England born during two eras (2006–2011 and 2014–2018); to assess demographic and care factors influencing weight gain.

Methods

Data for infants born before 32 weeks of gestation during 2014–2018 in England were obtained (29 687 infants). Weight gain modelled using SuperImposition by Translation And Rotation (SITAR), with infants grouped by gestational week. A cohort from 2006 to 2011 was used for comparison (3288 infants). Multiple linear regression was used to assess factors influencing change in weight SD score from birth to 36 weeks postmenstrual age.

Results

Weight gain velocity (termed ‘intensity’ in SITAR models) was greater in the more recent cohort for all gestation groups born before 30 weeks of gestation. After adjustment for gestation, birth weight and other perinatal factors, care elements associated with faster weight gain included delivery in a level 3 unit (0.09 SD less weight gain deficit, 95% CI: 0.07 to 0.10) and parenteral nutrition initiation during the first day of life (0.08 SD, 95% CI: 0.06 to 0.10). Factors associated with slower weight gain included early ventilation (−0.07 SD, 95% CI: −0.08 to −0.05) and less deprived neighbourhood (−0.012 SD per Index of Multiple Deprivation decile, 95% CI: −0.015 to −0.009).

Conclusions

Weight gain for extremely preterm infants was faster during 2014–2018 than during 2006–2011. Early initiation of parenteral nutrition and birth in a level 3 unit may contribute to faster weight gain.
Nasal high-flow therapy to Optimise Stability during Intubation: the NOSI pilot trial
Authors: Foran Jason , Moore Carmel Maria , Ni Chathasaigh Caitriona M , Moore Shirley , Purna Jyothsna R , Curley Anna
Published: October 2022

Objective

In adult patients with acute respiratory failure, nasal high-flow (NHF) therapy at the time of intubation can decrease the duration of hypoxia. The objective of this pilot study was to calculate duration of peripheral oxygen saturation below 75% during single and multiple intubation attempts in order to inform development of a larger definitive trial.

Design and setting

This double-blinded randomised controlled pilot trial was conducted at a single, tertiary neonatal centre from October 2020 to October 2021.

Participants

Infants undergoing oral intubation in neonatal intensive care were included. Infants with upper airway anomalies were excluded.

Interventions

Infants were randomly assigned (1:1) to have NHF 6 L/min, FiO21.0 or NHF 0 L/min (control) applied during intubation, stratified by gestational age (<34 weeks vs ≥34 weeks).

Main outcome measures

The primary outcome was duration of hypoxaemia of <75% up to the time of successful intubation,

Results

43 infants were enrolled (26 <34 weeks and 17 ≥34 weeks) with 50 intubation episodes. In infants <34 weeks’ gestation, median duration of SpO2of <75% was 29 s (0–126 s) vs 43 s (0–132 s) (p=0.78, intervention vs control). Median duration of SpO2 of<75% in babies ≥34 weeks’ gestation was 0 (0–32 s) vs 0 (0–20 s) (p=0.9, intervention vs control).

Conclusion

This pilot study showed that it is feasible to provide NHF during intubation attempts. No significant differences were noted in duration of oxygen saturation of <75% between groups; however, this trial was not powered to detect a difference. A larger, higher-powered blinded study is warranted.
Do adolescents with impaired vision have different intentions and ambitions for their education, career and social outcomes compared to their peers? Findings from the Millennium Cohort Study
Authors: Horvat-Gitsels Lisanne A , Cortina-Borja Mario , Rahi Jugnoo S
Published: October 2022

Background/aims

To investigate if impaired vision adversely impacts the intentions/ambitions of adolescents concerning their future education, careers and social outcomes.

Methods

Population-based birth cohort study in the UK comprising 9273 participants from the Millennium Cohort Study who were followed up to age 17 years. Children were classified as having normal vision or unilateral or bilateral impaired vision caused by significant eye conditions based on detailed parental-structured questionnaire data on sight problems and treatment coded by clinicians. Ten domains covering education, career and social outcomes by age 30 were investigated.

Results

Adjusted regression models showed few differences by vision status. Bilateral impaired vision was associated with increased odds of intending to remain in full-time education after statutory school age (adjusted OR (aOR) 2.00, 95% CI 1.08 to 3.68) and of home ownership at age 30 (aOR 1.83, 95% CI 1.01 to 3.32). Impaired vision was not associated with intending to attend university. A significantly higher proportion of parents of children with bilateral or unilateral impaired vision thought that their child would not get the exam grades required to go to university than parents of those with normal vision (29% or 26% vs 16%,p=0.026).

Conclusion

Adolescents with impaired vision have broadly the same intentions/ambitions regarding future education, careers and social outcomes as their peers with normal vision. The known significant gaps in attainment in these domains among young adults with vision impairment are therefore likely to be due to barriers that they face in achieving their ambitions. Improved implementation of existing interventions is necessary to ensure equality of opportunities.
Targeting cathepsin B by cycloastragenol enhances antitumor immunity of CD8 T cells via inhibiting MHC-I degradation
Authors: Deng Guoliang , Zhou Lisha , Wang Binglin , Sun Xiaofan , Zhang Qinchang , Chen Hongqi , Wan Ning , Ye Hui , Wu Xiaoqi , Sun Dongdong , Sun Yang , Cheng Haibo
Published: October 2022

Background

The loss of tumor antigens and depletion of CD8 T cells caused by the PD-1/PD-L1 pathway are important factors for tumor immune escape. In recent years, there has been increasing research on traditional Chinese medicine in tumor treatment. Cycloastragenol (CAG), an effective active molecule inAstragalus membranaceus, has been found to have antiviral, anti-aging, anti-inflammatory, and other functions. However, its antitumor effect and mechanism are not clear.

Methods

The antitumor effect of CAG was investigated in MC38 and CT26 mouse transplanted tumor models. The antitumor effect of CAG was further analyzed via single-cell multiomics sequencing. Target responsive accessibility profiling technology was used to find the target protein of CAG. Subsequently, the antitumor mechanism of CAG was explored using confocal microscopy, coimmunoprecipitation and transfection of mutant plasmids. Finally, the combined antitumor effect of CAG and PD-1 antibodies in mice or organoids were investigated.

Results

We found that CAG effectively inhibited tumor growth in vivo. Our single-cell multiomics atlas demonstrated that CAG promoted the presentation of tumor cell-surface antigens and was characterized by the enhanced killing function of CD8+T cells. Mechanistically, CAG bound to its target protein cathepsin B, which then inhibited the lysosomal degradation of major histocompatibility complex I (MHC-I) and promoted the aggregation of MHC-I to the cell membrane, boosting the presentation of the tumor antigen. Meanwhile, the combination of CAG with PD-1 antibody effectively enhanced the tumor killing ability of CD8+T cells in xenograft mice and colorectal cancer organoids.

Conclusion

Our data reported for the first time that cathepsin B downregulation confers antitumor immunity and explicates the antitumor mechanism of natural product CAG.
Territories within groups: the dynamic competition of drift-feeding juvenile Chinook salmon in 3-dimensional space
Authors: Neuswanger Jason R. , Rosenberger Amanda E. , Wipfli Mark S. , Hughes Nicholas F.
Published: October 2022

Salmonid populations are often regulated by territorial competition among juveniles for food and space. In the canonical view, salmonid territories are spaced horizontally across the river bottom in a two-dimensional mosaic. However, some juveniles instead feed in tight, three-dimensional (3-D) social groups. To investigate whether territoriality is possible within such groups, we applied a new concept—the momentary home range—to quantify the size, exclusivity, and temporal dynamics of 3-D space use by juvenile Chinook salmon ( Oncorhynchus tshawytscha) in the Chena River, AK. Individual strategies spanned a broad continuum of exclusivity and stationarity. However, some of the largest, most dominant fish in each group aggressively defended stationary, exclusive feeding spaces and thus were unambiguously territorial. Transient floaters entered and left the group quickly. A majority of fish were not aggressive but nevertheless occupied exclusive, stationary spaces that probably function as territories with regard to resource distribution and population regulation. The presence of territoriality within social groups, in a 3-D configuration, expands the known domain of this important behavior.
Increased endothelin-1 levels in coronary artery disease with diabetes mellitus in an Indonesian population
Authors: Inggriani Maria Patricia , Musthafa Ahmad , Puspitawati Ira , Fachiroh Jajah , Dewi Fatwa Sari Tetra , Hartopo Anggoro Budi
Published: October 2022

Diabetes mellitus (DM) increases risk of coronary artery disease (CAD). Endothelin-1 (ET-1) is a potential biomarker of endothelial dysfunction. This study aimed to evaluate ET-1 level in CAD patients and its relationship with DM. The cross-sectional design included subjects with angiographically proven CAD and controls among Indonesian. DM was defined by medical history and anti-diabetics use. Serum ET-1 level was measured in both subject groups. We recruited 305 subjects, 183 CAD patients and 122 controls. CAD subjects had higher percentage of males, DM, hypertension, dyslipidemia, smoking, family history of cardiovascular disease, and obesity. ET-1 level was significantly higher in CAD than in controls (2.44 ± 1.49 pg/mL vs. 1.76 ± 0.83 pg/mL; p < 0.001). Increased ET-1 level was significantly associated with DM and dyslipidemia. The highest ET-1 level was observed in CAD with DM, followed by CAD non-DM (2.79 ± 1.63 pg/mL vs. 2.29 ± 1.40 pg/mL; p = 0.023). Among controls, ET-1 level was the lowest in non-DM subjects. Female CAD had higher proportion of DM; however, ET-1 level was similar to male CAD with DM. In conclusion, an increased ET-1 level was significantly associated with DM in patients with CAD. Further research should investigate the potential role of ET-1 receptor antagonists in the secondary prevention of CAD with DM.
Effect of variable retention forestry on wood frogs (Lithobates sylvaticus) in early successional boreal mixedwood forests
Authors: Robinson Matthew , Nielsen Scott E. , Eaton Brian , Paszkowski Cynthia
Published: October 2022

Variable retention forest harvesting aims to reduce negative effects of harvesting on forest biodiversity, but knowledge gaps remain regarding its effects on some taxa over longer post-harvest time frames. To better understand effects of variable retention and environmental features on amphibians, we used pitfall traps to capture wood frogs ( Lithobates sylvaticus (LeConte, 1825)) across four levels of retention (clearcut (0%), 20%, 50%, and unharvested control (100%)), and two forest types (deciduous and coniferous), in 17-year post-harvest forests in northwest Alberta. We mapped breeding sites and used a LiDAR-based terrain moisture index (depth-to-water) to examine relationships between relative abundance, breeding site proximity, and soil moisture. Retention level alone had no effect on relative abundance of adult wood frogs, but in late summer (July and August), there was a significant interaction between retention level and forest type: capture rates decreased with retention level for deciduous forests, but increased with retention level in conifer forests. During late summer, capture rates were higher in conifer forests than deciduous forests, with soil moisture (lower depth-to-water) positively related to capture rates. Though timber retention may be beneficial to wood frogs in the short term, any impacts of forest harvesting on wood frog abundance were undetectable in stands 17 years post-harvest.
Groupoids and Hermitian Banach *-algebras
Authors: Austad A. , Ortega Eduard
Published: October 2022

We study when the twisted groupoid Banach *-algebra [Formula: see text] is Hermitian. In particular, we prove that Hermitian groupoids satisfy the weak containment property. Furthermore, we find that for [Formula: see text] to be Hermitian it is sufficient that [Formula: see text] is Hermitian. Moreover, if [Formula: see text] is ample, we find necessary conditions for [Formula: see text] to be Hermitian in terms of the fibers [Formula: see text].
Computational fluid dynamic investigating the reactive species transfer across the interface of a single rising bubble
Authors: Sattari Seyed Assadollah , Shahraki Farhad , Samkhaniani Nima , Atashi Hossein
Published: October 2022

This study implements a new solver (reactiveInterFoam) to simulate the component mass transfer alongside deformable gas–liquid interfaces. Mass transfer from the rising bubble in a quiescent Newtonian fluid is simulated. An effect of bubble hydrodynamics on the simultaneous diffusion reaction and selectivity of the cyclohexane oxidation process is investigated on a two-dimensional axisymmetric domain. The color function volume of fluid (CF-VoF) technique is applied to capture the deformable interface, and the continuous species transfer method is used to monitor the gas–liquid mass transfer behavior. Several simulations have been conducted to validate the model reliability to forecast component mass transfer from the bubble to the liquid phase, bubble shape, and flow field. Simulation findings approved that the rate of mass transfer is a function of boundary’s concentration, layer thickness, and bubble surface area. Furthermore, the selectivity increases by decreasing bubble diameter in both spherical and ellipsoidal regimes. The small bubbles with a lower Reynolds number have higher average selectivity. Comparing the simulated bubble shape and the grace chart indicates that the suggested numerical method can perfectly predict bubble regimes. The absolute average relative deviation (AARD%) of 14.59% has been observed between the terminal velocities predicted by the numerical simulation and six experimental measurements.
Casson fluid flow in a vertical annulus through porous medium with heat transfer characteristics and chemical reaction: An exact solution
Authors: Olkha Amala , Kumar Mukesh
Published: October 2022

This study explores heat and mass transport in natural convection of Casson fluid in a vertical annulus via porous medium. Impacts of thermal radiation, heat source and chemical reaction are taken into consideration. The equations representing the model reduced into nondimensional ordinary differential equations under adequate transformations are solved analytically. Closed form solutions are obtained for the problem in terms of Bessel’s functions. Influences of various arising parameters such as porous medium parameter, heat generation, thermal radiation, thermal Grashof number, solutal Grashof number, etc. on flow, temperature and concentration fields are exhibited by graphs and discussed. Also, we have solved the problem numerically on MATLAB software employing the bvp4c technique along with shooting technique. The exact and numerical solutions compared found a good match. Moreover, the effects of numerous parameters on quantities of physical importance such as skin-friction coefficient, Nusselt number and Sherwood number are also portrayed and discussed. Heat exchangers, energy storage systems such as batteries and inverters, thermal storage and thermal protection systems are some examples of applications of the study.
An Exact Solution Method for the Political Districting Problem
Authors: Chopra Sunil , Park Hyunwoo , Shim Sangho
Published: October 2022

Mehrotra, Johnson, and Nemhauser (1998) [Management Science 44, pp. 1100–1114] addressed a problem for political districting and developed an optimization based heuristic to find good districting plans which partition the population units into contiguous districts with equal populations. Their case study found a good South Carolina plan at a penalty cost of 68. This paper develops a strong integer programming model identifying the exact optimal solution. Our model identifies the optimal South Carolina plan at the minimum penalty of 64. Motivated by the 2019 lawsuit challenging the congressional plan as gerrymandering, we inspect the actual Maryland plan.
Construction Technique and Evaluation of High Performance t-bit Burst Error Correcting Codes for Protecting MCUs
Authors: Maity Raj Kumar , Samanta Jagannath , Bhaumik Jaydeb
Published: October 2022

The occurrences of Multiple Cell Upset (MCU) are more liable to arise in modern memory systems with the continuous upgradation of microelectronics technology from micron to deep submicron scales. These MCUs are mainly induced due to radiations in memory systems. Error Correcting Codes (ECCs) with lower design complexity are generally preferred for the mitigation of MCUs. The major drawback of the existing ECC is requiring higher overheads as error correction capability increases. In this paper, authors have proposed a new class of high performance [Formula: see text]-bit Burst Error Correcting (BEC) codes. Parity check matrices ([Formula: see text]) have been proposed for 3-bit and 4-bit BEC codes with word lengths of 16-bit, 32-bit and 64-bit. Also a simplified decoding scheme has been introduced for these codes. The proposed codecs have been designed and implemented in FPGA and ASIC platforms. The proposed codecs are compact in area, faster in speed and efficient in power compared to existing related schemes. But these lower design constrains are achieved at the cost of increase in redundancy. So, the proposed codecs can be employed in applications where redundancy is not the only constrain for correcting [Formula: see text]-bit burst errors caused by MCUs.
GOKA: A Network Partition and Cluster Fusion Algorithm for Controller Placement Problem in SDN
Authors: Xiao Changwei , Chen Jue , Qiu Xihe , He Dun , Yin Hanmin
Published: October 2022

Software Defined Networking (SDN) is a new promising network architecture, with the property of decoupling the data plane from the control plane and centralizing the network topology logically, making the network more agile than traditional networks. However, with the continuous expansion of network scales, the single-controller SDN architecture is unable to meet the performance requirements of the network. As a result, the logically centralized and physically separated SDN multi-controller architecture comes into being, and thereupon the Controller Placement Problem (CPP) is proposed. In order to minimize the propagation latency in Wide Area Network (WAN), we propose Greedy Optimized K-means Algorithm (GOKA) which combines K-means with greedy algorithm. The main thought is to divide the network into multiple clusters, merge them greedily and iteratively until the given number of controllers is satisfied, and place a controller in each cluster through the K-means algorithm. With the purpose of proving the effectiveness of GOKA, we conduct experiments to compare with Pareto Simulated Annealing (PSA), Adaptive Bacterial Foraging Optimization (ABFO), K-means and K-means[Formula: see text] on 6 real topologies from the Internet Topology Zoo and Internet2 OS3E. The results demonstrate that GOKA has a better and more stable solution than other four heuristic algorithms, and can decrease the propagation latency by up to [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] in contrast to PSA, ABFO, K-means and K-means[Formula: see text], respectively. Moreover, the error rate between GOKA and the best solution is always less than [Formula: see text], which promises the precision of our proposed algorithm.
The Effect of Environmental Metrics on Software Fault Prediction
Authors: Odabasi Merve , Gul Ensar
Published: October 2022

In this study, besides the software metrics, the environmental metrics such as experience of software engineer, similar project experience, size of the project, programming language, time spent on analysis and development are also explored to see whether they also affect the results of software fault prediction and what would be the success rates. The dataset for this study was generated from combining various data from 10 projects. A total of 36 metrics and 6676 test cases were evaluated. The errors occurred in the test cases are not just considered as an error, their priority and cases that cannot be tested are also taken into consideration. Nine fault levels are employed in models. Models are created with four different algorithms which have achieved a success rate of; 76% by the decision tree algorithm, 94% by the nearest neighbors algorithm, 90% by the random forests algorithm and 73% by the Adaboost Classifier Algorithm. It was observed that environmental metrics are indeed effective in software fault prediction and when applied with machine learning algorithms a high rate of success can be achieved.
Structures of homomorphisms induced by arc selection game and arc freeze selection game
Authors: Kinuno Rin
Published: October 2022

In this paper, we study the structures of homomorphisms induced from “Arc selection game” and “Arc freeze selection game” based on the knot theory. As a result, we give necessary and sufficient conditions for the games to be cleared, and show how many solutions exist. Also, we show that local moves on knot diagrams related with the games are unknotting operations.
The shadow of charged traversable wormholes
Authors: Neto Mário Raia , Perez Daniela , Pelle Joaquin
Published: October 2022

In this paper, we compute the shadow cast by a charged Morris–Thorne wormhole when the light source is a star located beyond the mouth which is opposite to the observer. First, we provide an extensive analysis of the geodesic properties of the spacetime, both for null and massive particles. The geometrical properties of this solution are such that independently of the viewing angle, some light rays always reach the observer. Additionally, the structure of the images is preserved among the different values of the charge and scales proportionally to the charge value.
Conformable fractional study of nuclear energy excitation by Bohr Hamiltonian with screened Kratzer potential for triaxial nuclei
Authors: Ndjobo J. P. , Likéné A. Atangana , Ahmadou K. , Tsila P. Mah , Ben-Bolie G. H.
Published: October 2022

In this work, we obtain new solutions of the Bohr Hamiltonian model appropriate for triaxial nuclei, with screened Kratzer potential in the framework of conformable fractional derivative. The analytical solutions for energy spectra are obtained using the conformable fractional Nikiforov–Uvarov method. We discuss the link between the present model and other relevant related models such as Z(5) model, classical screened Kratzer model and conformable fractional Kratzer model. The effect of the fractional-order parameter is investigated on the variations of the interaction potential. The normalized eigen-energies are calculated as well as normalized B(E2) transitions probabilities at different values of the fractional-order parameter. Our results reproduced well the experimental data for [Formula: see text]Xe, [Formula: see text]Xe, [Formula: see text]Xe, [Formula: see text]Pt, [Formula: see text]Pt and [Formula: see text]Pt atomic nuclei, and are found to be improved in comparison with other related theoretical models.
Generalized Plastic Hinge Method for Failure Analysis of Steel Framed Structures
Authors: Yang LuFeng , Bai DaLian , Ju J. Woody
Published: October 2022

For steel framed structures with small geometric nonlinearity, the conventional first-order plastic hinge method (FPHM) estimates rapidly the failure mode and ultimate strength of frames according to the proportionality property. However, it ignores the combined action of multiple internal forces on the development of plastic hinge, leading to mistakes in estimating the failure mode and ultimate strength of frames. Though the second-order plastic hinge method (SPHM) and the refined plastic hinge method (RPHM) overcome this problem, they lose the FPHM’s proportionality property and the high efficiency of computation as well. In this paper, the generalized plastic hinge method (GPHM) featuring proportionality property is proposed for steel framed structures to overcome the drawbacks of the conventional FPHM, the SPHM and the RPHM. Firstly, a linearly elastic analysis is performed on the steel framed structure between the formation of any two plastic hinges; then the strength reduction factor is developed by means of the generalized yield criterion (GYC) for modification of the sectional strength of frame component under multiple internal forces during loading process. Secondly, the element bearing ratio (EBR) is defined on the basis of the homogeneous generalized yield function and is in proportion to the loading, so that the position of generalized plastic hinge and the corresponding load increment are determined for each loading step according to this proportional property. Furthermore, the balance vector is developed by means of the GYC and the slope-deflection relation to modify the result of the calculated load increment. Finally, several examples are presented to validate the much higher computational efficiency and accuracy of the proposed method by comparing it with the plastic zone analysis (PZA), the SPHM and the conventional FPHM.
Cyclic Behavior and Modeling of Reinforced Concrete Shear Walls Based on Enhanced Bond-Based Peridynamics
Authors: Zhang Ning , Gu Quan , Yang T. Y. , Huang Surong
Published: October 2022

Peridynamics (PD) has gained increasing usage in simulating the nonlinear damage behavior of reinforced concrete (RC) structures due to its extraordinary capacity in solving discontinuous problems. This paper presents an enhanced bond-based peridynamic (BPD) modeling method for simulating the complex nonlinear behavior of RC shear walls, such as strength deterioration and cracking propagation, under cyclic loading conditions. In the proposed BPD method, a novel concrete bond model is presented that can consider the stiffness degradation, strength deterioration, and residual plastic deformation. A steel model and a coupled axial-shear model are adopted to simulate the nonlinear behavior of rebar and reinforcement-concrete interaction. The enhanced PD is implemented in an open-source finite element software framework, OpenSees, and can perform implicit or explicit, dynamic or static analyses in a parallel manner. Two RC shear walls under cyclic loading conditions are used as verification examples. The nonlinear damage behavior is studied in detail for the RC shear walls, e.g. the strength deterioration, pinch effect, and cracking behavior. The results demonstrate that the enhanced BPD modeling approach is capable of simulating the nonlinear damage behavior of RC shear walls under cyclic loading conditions.
The Krull dimension-dependent elements of a Noetherian commutative ring
Authors: Babaei S. , Sevim E. Sengelen
Published: October 2022

In this paper, we introduce the Krull dimension-dependent elements of a Noetherian commutative ring. Let [Formula: see text] be non-unit elements of a commutative ring [Formula: see text]. [Formula: see text] are called Krull dimension-dependent elements, whenever [Formula: see text] We investigate the elements of a ring according to this property. Among the many results, we characterize the rings that all elements of them are Krull dimension-dependent and we call them, closed under the Krull dimension. Moreover, we determine the structure of the rings with Krull dimension at most 1, that are closed under the Krull dimension.
Optimality of the rescaled pure greedy learning algorithms
Authors: Zhang Wenhui , Ye Peixin , Xing Shuo
Published: October 2022

We propose the Rescaled Pure Greedy Learning Algorithm (RPGLA) for solving the kernel-based regression problem. The computational complexity of the RPGLA is less than the Orthogonal Greedy Learning Algorithm (OGLA) and Relaxed Greedy Learning Algorithm (RGLA). We obtain the convergence rates of the RPGLA for continuous kernels. When the kernel is infinitely smooth, we derive a convergence rate that can be arbitrarily close to the best rate [Formula: see text] under a mild assumption of the regression function.
Fabrication of Silicon Dioxide (SiO2) Nanoparticles Using Wastes of Fruit’s Peel: Characterization and Biological Activities
Authors: Ajmal Noushin , Saraswat Keerti , Alharthi Abdurrahman I. , Alotaibi Mshari , Ansari Mohammed Javed , Ahsan Mohammed Jawed , Bakht Md. Afroz
Published: October 2022

Metal nanoparticles use a biocompatible, environmentally sustainable approach to be used as therapeutic nanomedicine. This study describes the use of rosaceous fruit peel waste extract (plum, kiwi, peach) as a tool for the synthesis of silicon nanoparticles. Visual color shift was used to identify biosynthesized SiO2NPs at first. Some characterization techniques, such as X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and SEM analysis, verified the existence of these metal nanoparticles. The presence of various functional groups from the extract secondary metabolites for nanoparticle synthesis is suggested by FT-IR spectroscopy. The existence of SiO2 nanoparticles, whether crystalline or amorphous, is hypothesized using XRD. The formation of SiO2 nanoparticles was confirmed by UV–Vis spectroscopy. The zeta potential shows the nanoparticles stability. Different fruits peels produced different shapes and sizes of SiO2NPs. Plum peels extract produced the smallest SiO2NPs, followed by kiwi and peach as determined by SEM analysis. Antibacterial and antioxidant activities were also tested on all of the synthesized SiO2NPs. Regardless of size; these nanoparticles have stronger antibacterial activity against gram-negative bacteria. All SiO2NPs’ antioxidant activity was measured in a size and dose-dependent manner. To summarize, the current environmentally friendly method for the synthesis of SiO2NPs nanoparticles is a simple and economical process with good antibacterial and antioxidant properties.
Enhanced Photoelectrochemical Performance of Co/TiO2Nanotubes Prepared by Electrodeposition
Authors: Wang Xueqin , Dai Man , Chen Qihui , Qiao Peng , Liu Ying , Wang Wenyi , Wang Yuanyuan , Song Hua
Published: October 2022

TiO2nanotube arrays (NTbs) have been widely used in the field of photocatalysis due to their large surface area, good controllability and superior electron transport properties. However, due to its wide bandgap (3.2[Formula: see text]eV), pure TiO2can only be excited by ultraviolet light ([Formula: see text][Formula: see text]nm), leading to low utilization of solar energy. Second, the high recombination rate of the photogenerated electrons and holes ([Formula: see text]/[Formula: see text] pair also reduces the quantum efficiency of TiO2. In order to realize the efficient photocatalytic activity of TiO2nanomaterials, it is necessary to design the TiO2nanomaterials to optimize the utilization of the solar spectrum. In this study, TiO2NTbs were obtained by the anodizing method using titanium foil, and a series of Co/TiO2NTbs were prepared by electrochemical deposition. The effects of the deposition voltage on the physical and photocatalytic properties of the Co/TiO2NTbs were investigated. Results found that the Co/TiO2NTbs had the highest photocurrent density 0.7[Formula: see text]mA/cm2at an electrodeposition time of 60[Formula: see text]s and a voltage of 1[Formula: see text]V, and the photoelectric conversion efficiency was 15.85%, which was approximately 2.8 times that of the pure TiO2NTbs. The degradation rate of Rhodamine B of the Co/TiO2NTbs in 120[Formula: see text]min was 76.3%, whereas that of the pure TiO2NTbs was only 48.7%. The forbidden bandwidth of the Co/TiO2NTbs was reduced to 3.02[Formula: see text]eV, whereas that of the pure TiO2NTbs was 3.2[Formula: see text]eV.
Star chromatic number of some graph products
Authors: Ghazi Ghazale , Rahbarnia Freydoon , Tavakoli Mostafa
Published: October 2022

A star coloring of a graph [Formula: see text] is a proper vertex coloring in which every path on four vertices uses at least three distinct colors. Equivalently, in a star coloring, the induced subgraphs formed by the vertices of any two colors have connected components that are star graphs. A graph [Formula: see text] is [Formula: see text]- star-colorable if there exists a star coloring of [Formula: see text] from a set of [Formula: see text] colors. The minimum positive integer [Formula: see text] for which [Formula: see text] is [Formula: see text]-star-colorable is the star chromatic number of [Formula: see text] and is denoted by [Formula: see text]. In this paper, upper and lower bounds are presented for the star chromatic number of the rooted product, hierarchical product, and lexicographic product.