bluuebunny/crossref_metadata_2025 huggingface dataset:
Explainable artificial intelligence for cough-related quality of life impairment prediction in asthmatic patients
Authors: Narteni Sara , Baiardini Ilaria , Braido Fulvio , Mongelli Maurizio
Published: March 2024

Explainable Artificial Intelligence (XAI) is becoming a disruptive trend in healthcare, allowing for transparency and interpretability of autonomous decision-making. In this study, we present an innovative application of a rule-based classification model to identify the main causes of chronic cough-related quality of life (QoL) impairment in a cohort of asthmatic patients. The proposed approach first involves the design of a suitable symptoms questionnaire and the subsequent analyses via XAI. Specifically, feature ranking, derived from statistically validated decision rules, helped in automatically identifying the main factors influencing an impaired QoL: pharynx/larynx and upper airways when asthma is under control, and asthma itself and digestive trait when asthma is not controlled. Moreover, the obtained if-then rules identified specific thresholds on the symptoms associated to the impaired QoL. These results, by finding priorities among symptoms, may prove helpful in supporting physicians in the choice of the most adequate diagnostic/therapeutic plan.
Choline supplementation: Impact on broiler chicken performance, steatosis, and economic viability from from 1 to 42 days
Authors: Ramalho de Lima Matheus , Kaneko Isabelle Naemi , de Lima Adiel Vieira , de Melo Lucas Nunes , de Lima Mario Cesar , de Brito Anna Neusa Eduarda Ferreira , Costa Fernando Guilherme Perazzo , Boas Andreia D. C. Vilas , Toledo Ana Louise , Ferrer Sigfrido Lopez , Marimuthu Saravanakumar
Published: March 2024

This study was carried out to compare the impact of choline supplementation (available from two sources synthetic and natural) on various dosages in broilers. The mode of choline supplementation, via diet and additional sources, synthetic and natural, and the data of performance, carcass quality, blood parameters, and hepatic steatosis were compared. A total of 1050 day-old male Cobb 500 broiler chicks were randomly assigned to 10 treatments, using a completely randomized design model in a factorial scheme, with 6 replicates per treatment and 25 birds per replicate. Choline was supplemented using three sources: synthetic choline chloride 60% (CC), and two sources of natural choline A (NCA), and B (NCB). The Control treatment did not receive any choline supplementation. The diets were supplemented with low, intermediate and high doses of choline sources (400g/t, 800g/t, and 1200g/t of CC; 100g/t, 200g/t, and 300g/t of both NCA and NCB). Data analysis was performed using a factorial model to investigate the effects of choline supplementation (CC, NCA, NCB) and doses on the measured variables. Overall, the results indicated that the the performance of NCA was better than CC & NCB, specifically the dose of 100g/t of NCA outperformed MAR at 100g/t & CC at 400g/t, leading to a significant increase in body weight gain (85.66g & 168.84g respectively), and a noteworthy (9- & 12-point respectively) improvement in feed conversion ratio. Furthermore, NCA contributed to a reduction in steatosis when contrasted with various NCB & CC doses, likely due to the presence of curcumins and catechins in the natural choline source. These findings demonstrated that NCA supplementation yielded superior results compared to CC and NCB across both performance and liver health aspects in broilers aged 1 to 42 days. In conclusion, NCA can be used to replace the CC 60% without compromise on the zootechnical performance in broilers.
How COVID-19 affects voting for incumbents: Evidence from local elections in France
Authors: Morisi Davide , Cloléry Héloïse , Kon Kam King Guillaume , Schaub Max
Published: March 2024

How do voters react to an ongoing natural threat? Do voters sanction or reward incumbents even when incumbents cannot be held accountable because an unforeseeable natural disaster is unfolding? We address this question by investigating voters’ reactions to the early spread of COVID-19 in the 2020 French municipal elections. Using a novel, fine-grained measure of the circulation of the virus based on excess-mortality data, we find that support for incumbents increased in areas that were particularly hard hit by the virus. Incumbents from both left and right gained votes in areas more strongly affected by COVID-19. We provide suggestive evidence for two mechanisms that can explain our findings: an emotional channel related to feelings of fear and anxiety, and a prospective-voting channel, related to the ability of incumbents to act more swiftly against the diffusion of the virus than challengers.
Association between multiple sclerosis and cancer risk: A two-sample Mendelian randomization study
Authors: Liu Zeyu , Fan Teng , Mo Xiaoyan , Kan Jun , Zhang Bei
Published: March 2024

Multiple Sclerosis (MS) is an immune-related disease and the relationship between MS and cancer has raised attention. Previous studies of the relationship between MS and cancer have reached conflicting conclusions. In this study, the two-sample MR method is used to investigate whether MS has a causal correlation with cancers and offer scientific evidence for cancer prevention. Single nucleotide polymorphisms (SNPs) related to MS were obtained from the genome-wide association study (GWAS) based on International Multiple Sclerosis Genetics Consortium (IMSGC) and SNPs related to 15 types of cancers were obtained from the GWASs based on UK Biobank. Inverse variance weighted (IVW) method was mainly used to assess causal effects. Sensitivity analyses were conducted with Cochran’s Q-test, MR Egger intercept, leave-one-out test, and MR Steiger method. IVW analysis showed that MS was only associated with a marginal increased risk of cervical cancer (OR 1.0004, 95% CI 1.0002–1.0007, p = 0.0003). Sensitivity analyses showed that the results of MR analysis were robust and found no heterogeneity, no pleiotropy, and no reverse causation. In conclusion, this study finds no causal relationship between MS and 15 types of cancers except cervical cancer.
Research on distributionally robust energy storage capacity allocation for output fluctuations in high permeability wind and solar distribution networks
Authors: Wang Xin , Sun Bo , Ge Cheng , Liu Qian , Li Zhiwei , Huang Mengqi
Published: March 2024

This paper presents a novel approach to addressing the challenges associated with energy storage capacity allocation in high-permeability wind and solar distribution networks. The proposed method is a two-phase distributed robust energy storage capacity allocation method, which aims to regulate the stochasticity and volatility of net energy output. Firstly, an energy storage capacity allocation model is established, which considers energy storage’s investment and operation costs to minimize the total cost. Then, a two-stage distributed robust energy storage capacity allocation model is established with the confidence set of uncertainty probability distribution constrained by 1-norm and ∞-norm. Finally, a Column and Constraint Generation (C&CG) algorithm is used to solve the problem. The validity of the proposed energy storage capacity allocation model is confirmed by examining different wind and solar penetration levels. Furthermore, the model’s superiority is demonstrated by comparing it with deterministic and robust models.
Prevalence and genome features of lake sinai virus isolated from Apis mellifera in the Republic of Korea
Authors: Nguyen Thi-Thu , Yoo Mi-Sun , Truong A-Tai , Youn So Youn , Kim Dong-Ho , Lee Se-Ji , Yoon Soon-Seek , Cho Yun Sang
Published: March 2024

Lake Sinai Virus (LSV) is an emerging pathogen known to affect the honeybee (Apis mellifera). However, its prevalence and genomic characteristics in the Republic of Korea (ROK) remain unexplored. This study aimed to assess the prevalence of and analyze the LSVs by examining 266 honeybee samples from the ROK. Our findings revealed that LSV exhibited the highest infection rate among the pathogens observed in Korean apiaries, particularly during the reported period of severe winter loss (SWL) in A. mellifera apiaries in 2022. Three LSV genotypes– 2, 3, and 4 –were identified using RNA-dependent RNA polymerase gene analysis. Importantly, the infection rates of LSV2 (65.2%) and LSV3 (73.3%) were significantly higher in colonies experiencing SWL than in those experiencing normal winter loss (NWL) (p < 0.03). Furthermore, this study provides the first near-complete genome sequences of the Korean LSV2, LSV3, and LSV4 strains, comprising 5,759, 6,040, and 5,985 nt, respectively. Phylogenetic analysis based on these near-complete genome sequences demonstrated a close relationship between LSVs in the ROK and China. The high LSV infection rate in colonies experiencing a heightened mortality rate during winter suggests that this pathogen might contribute to SWL in ROK. Moreover, the genomic characteristic information on LSVs in this study holds immense potential for epidemiological information and the selection of specific genes suitable for preventing and treating LSV, including the promising utilization of RNA interference medicine in the future.
Short-term power load forecasting method based on Bagging-stochastic configuration networks
Authors: Pang Xinfu , Sun Wei , Li Haibo , Liu Wei , Luan Changfeng
Published: March 2024

Accurate short-term load forecasting is of great significance in improving the dispatching efficiency of power grids, ensuring the safe and reliable operation of power grids, and guiding power systems to formulate reasonable production plans and reduce waste of resources. However, the traditional short-term load forecasting method has limited nonlinear mapping ability and weak generalization ability to unknown data, and it is prone to the loss of time series information, further suggesting that its forecasting accuracy can still be improved. This study presents a short-term power load forecasting method based on Bagging-stochastic configuration networks (SCNs). First, the missing values in the original data are filled with the average values. Second, the influencing factors, such as the weather- and week-type data, are coded. Then, combined with the data of influencing factors after coding, the Bagging-SCNs integration algorithm is used to predict the short-term load. Finally, by taking the daily load data of Quanzhou City, Zhejiang Province as an example, the program of the abovementioned method is compiled in Python language and then compared with the long short-term memory neural network algorithm and the single-SCNs algorithm. Simulation results show that the proposed method for medium- and short-term load forecasting has a high forecasting accuracy and a significant effect on improving the accuracy of load forecasting.
The impact of aerobics on mental health and stress levels: A visualization analysis of the CiteSpace map
Authors: Zhao Jianxin , Bai Yabing , Yang Yongjing , Li Xiaolei
Published: March 2024

This study aims to integrate research in the field of aerobics and mental health through the visualization analysis method of the CiteSpace map, to clarify the impact of aerobics on mental health and stress levels. Firstly, based on the literature method, pieces of literature related to aerobics and mental health are searched and collected. Secondly, the visualization analysis method of the CiteSpace map is employed to summarize and analyze the contents of the literature, involving statistical analysis of the annual number of publications, analysis of author characteristics, and analysis of publishing institution characteristics. In addition, keyword co-occurrence analysis and keyword cluster analysis are also conducted in related research fields. Among them, the Log-Likelihood Ratio is used in keyword cluster analysis. Finally, the results are analyzed using the visualization analysis method of the CiteSpace map and the statistics-based comprehensive results. The results demonstrate that in the recent 20 years, the average annual number of articles in related fields exceeds 190. The high-yield authors are distributed in economically developed areas, and the cooperation among authors is scattered. In the keyword clustering results, a total of 77 cluster labels are obtained. The Q value of the clustering module is 0.89, and the average clustering profile silhouette (S) value is 0.92, indicating that the clustering structure is significant and the results are reasonable. The aerobics cluster contains the most closely related keywords, covering mental health and stress levels. Data analysis based on existing studies reveals that aerobics has a significant impact on mental health and stress levels. Individuals participating in aerobics show obvious improvement in mental health inventory (MHI) scores (t(100) = 4.32, p<0.05). Individuals participating in aerobics present a remarkable reduction in the questionnaire evaluation of stress levels (t(100) = -3.91, p<0.05). This study’s results support aerobics’ positive effects on mental health and stress levels.
Writing outward into the international world
Authors: Ihimaera Witi
Published: March 2024

This was written first as a keynote speech, which was given at the midway point of the 27th annual conference of the New Zealand Studies Association, held in Stockholm, Sweden, and Turku, Finland, 26–30 June 2023. It was originally entitled ‘The Māori anthologist’ and addressed the politics and aesthetics of my career as an editor of some sixteen anthologies of, mainly, Māori and New Zealand literature. But after listening to the papers that had been presented, which primarily covered the South Pacific, I decided to alter my presentation and offer a personal intervention on my career as a Pacific rather than a Māori writer, ranging from The Whale Rider (1987) through to Navigating the Stars: Māori Creation Myths (2020). Furthermore, the presentation now responded to themes of Pacific and Oceanic transnationality and transculturality, which had arisen from the conference. This article is both a consolidation and extension of thoughts and arguments that were given in that keynote speech, with identity and indigeneity key concerns.
Intermittent Patterns in Turbulence Produced by a Conventional Fractal Square Grid and a Spaced Fractal Square Grid
Authors: Ben Mahjoub O. , Ouadoud A.
Published: March 2024

Measurements of longitudinal velocity were conducted in an open-circuit suction wind tunnel at the Max-Planck Institute for Dynamics and Self-Organization in Gottingen. A hot wire anemometer was used at various positions within the turbulent flow generated by both a traditional fractal square grid (FSG) and a spaced fractal square grid (SFSG), both possessing similar physical properties. The results indicate the presence of self-similarity. Employing Extended Self Similarity (ESS), we performed a statistical characterization of this intricate turbulent system. We introduce a supplementary methodology suitable for non-homogeneous turbulence, founded on the analysis of the energy transfer hierarchy. The distinctive features of non-homogeneous characteristics within a turbulent field, discerned through nonlocal dynamics, are isolated from those conventionally attributed solely to intermittency. We propose a physical interpretation for the observed scale independence of relative scaling exponents in such non-homogeneous flows, elucidating the compensation effect of energy transfer on the contrast between strong coherent turbulent events and the less intense background turbulence. This approach enables the identification of whether intermittency arises from small scales or is associated with coherent structures.
Synchronization of Airflows at Varying Heights
Authors: Filimonova N. , Kellnerová R. , Bodnár T. , Friedmann E.
Published: March 2024

We propose a method to study the dynamics of energetic events in airflows at different heights. The method is based on a mathematical model for invariant pattern recognition by a visual system, which is combined with a wavelet analysis method. Here we use the first four Krawtchoukfunctions as the mother wavelets. The method allows to determine the time-frequency characteristics of the local impulse components for continuous signals. These extracted impulsecomponents of airflow velocities can be effectively utilized in cross-correlation analysis aimed at identifying potential synchronizations among airflows at different heights.
Kinetic Energy Dissipation Caused by the Vortical Structures in Linear Blade Cascade
Authors: Flídr E.
Published: March 2024

The dissipation of kinetic energy in a linear blade cascade has been extensively studied from both experimental and numerical perspectives. Nevertheless, the impact of vortices on kinetic energy dissipation in the cascade is often assessed under several assumptions that significantly simplify the situation and may underestimate their influence. The presented paper focuses on the kinetic energy dissipation caused by vortical structures. This investigation is based on a new approach to evaluate individual contributions to the overall kinetic energy dissipation in the cascade. Vortices are identified using the H criterion in this paper. A comparison of this new method with the commonly used approach is presented. The experimental research was performed on linear blade cascade with pitch-to-chord ratio t/c = 0.9 for both constant Mach and Reynolds numbers (M2,is =0.4 and Re2,is = 2.5 × 105) and for three different inlet flow angles (α1 = −20°; 5° and 30°).
Improvement of an Unbaffled Stirred Tank Mixing Characteristics Using Variable Speed Impeller
Authors: Gebouský O. , Haidl J. , Bodnár J. , Pivokonský M.
Published: March 2024

Unbaffled mixing tanks with magnetically driven impellers are increasingly used in biotechnological and pharmaceutical industries, combining the benefits of a closed, sterile environment with easy equipment cleanability. On the other hand, missing internals, such as baffles or cooling coils, have an adverse effect on the equipment mixing characteristics, namely the batch homogenization time. In our previous research, we uncovered that the eccentricity and inclination of the impeller – both employed routinely to enhance the mixing characteristics of unbaffled vessels – are not fully effective in the suppression of central vortex formation resulting in the increase in the homogenization time. In this work, we propose a simple solution to counteract the central vortex formation – a periodical variation of impeller rotational speed. This approach destabilizes the central vortex, significantly reducing homogenization time while maintaining the benefits of the original unbaffled setup. This innovation can seamlessly integrate into existing industrial setups, promising efficiency gains for biotech and pharmaceutical production.
Convergence of POD Modes for Cylinder Wake Flow
Authors: Hlavatý T. , Belda M. , Isoz M.
Published: March 2024

Proper orthogonal decomposition (POD) is a popular technique for both flow analysis and model order reduction. However, its applicability is strongly dependent on the amount of input data. In the present contribution, we investigate the convergence of numerical POD modes for the canonical case of turbulent flow in the wake behind a circular cylinder. In particular, the cylinder placed at a crossflow at Reynolds number of 4815 was simulated using detached eddy simulation (DES) with sufficient mesh resolution to achieve a large eddy simulation (LES) and direct numerical simulation (DNS) blend in the region of interest located directly behind the examined cylinder. The convergence of POD modes with respect to (i) the number of temporal snapshots used, (ii) the enforcement of the assumed symmetries, and (iii) spatial resolution of the CFD results was examined. Only the first eleven modes can be assumed converged when using standard POD and 12000 snapshots sampled at 2 kHz. However, the results may be significantly improved by enforcing symmetries in the data, which enables to converge even the fifteenth mode with a significantly lower number of snapshots. Finally, simple norm-based techniques did not proved to be a sufficient tool for POD toposes comparison. Therefore the quantitative evaluation of the modes convergence remains an open question.
Flow Simulations Approach for Flocculation Tanks
Authors: Idžakovičová K. , Bílek V. , Haidl J. , Isoz M. , Pivokonský M.
Published: March 2024

Flocculation in water treatment facilities plays a key role in the separation of colloidal inorganic and organic substances. Its optimization leads to a significant increase in its efficiency and savings of operational costs. However, it is currently based on trial-and-error experimental approaches. In this contribution, we focus on flow modeling in stirred flocculation tanks that would, after coupling with a calibrated model of particle aggregation, enable simulationbased flocculation optimization. Despite the abundance of literature on stirred tank modeling, there is no universal agreement on the methodology used to describe turbulence nor on the approach to the computational mesh creation. Consequently, there is no unified methodology for simulations and their validation. To address this, we present a best-practice methodology for economical, yet reliable flow simulations in the said device. This methodology includes the choice of the turbulence model, the approach to the design of a high quality mesh suitable for arbitrary geometries, and results evaluation. It is developed based on an extensive literature review, a multitude of flow simulations using several meshes of progressively higher quality and resolution, and various strategies to converge to steady-state flow conditions. The simulation quality indicators used here involve comparison with the experimental data on fluid velocity, stirrer power output, and flow rate through the impeller zone. Additionally, the resulting flow simulation models are compared using tracer transport simulations, hinting at their potential for coupling with particle aggregation models.
Delayed Detached Eddy Simulation of Thermal Mixing in T-Junction
Authors: Kořínek T. , Škarohlíd J. , Škoda R.
Published: March 2024

The reliability of a piping system is a key factor for the safe operation of nuclear power plants. Thermal mixing of two streams in a T-junction piping may lead to temperature fluctuations and corresponding high-cycle thermal fatigue. This may lead to the pipe’s wall’s failure and coolant leakage. The present study deals with numerical simulations of thermal mixing in a T-junction using the Delayed Detached Eddy Simulation turbulence model. Several inflow boundary conditions were investigated in order to analyze the influence of inflow conditions on thermal mixing.
Two-Phase 3D Modeling of an Airlift Pump in Openfoam
Authors: Koval S. O. , Dimitrieva N. F.
Published: March 2024

Airlift pumps use compressed gas to transport liquids and solid particles. Due to the lack of theoretical equations for airlift pump design and prediction of its flow regimes, numerical or experimental investigations must be carried out to find the best condition to operate it with high efficiency. For low volumetric fractions of small solid particles, the flow in airlift pumps may be simplified using a two phase approximation in which the solid phase is neglected. Then, the system corresponds to a liquid-gas mixture and its determining equations consist of the Navier-Stokes equation, continuity, energy conservation and the phase transport equation. This paper presents numerical studies on the optimization of air–water flow in an airlift pump. The studies were performed using a built-in OpenFOAM solver for the two-phase flow of two compressible fluids. The results of calculations are presented for different air mass-flow rates. The influence of gas mass flow rates on airlift efficiency was investigated.
On Linear Modelling of Axial Velocity Density Ratio Development in Compressor Blade Cascades
Authors: Kreuzová T. , Šimurda D. , Šafařík P.
Published: March 2024

Flow field in transonic compressor blade cascade is examined by means of numerical simulations. Quasi-3D simulations with an influence of axial velocity density ratio (AVDR) are performed. Results of the simulations are compared to data available in literature. It is shown that modelling of AVDR as a linear function does not provide accurate predictions.
Analysis of Boundary Conditions Properties in the SPH Method
Authors: Němeček J. , Halada T. , Beneš L.
Published: March 2024

This article deals with analysis of boudary conditions for meshfree Smoothed particle hydrodynamics method (SPH). Two variants of boundary condition were analyzed, Dynamic boundary condition (DBC) and Boundary integral (BI), on one simple case. Furthermore we introduce a possible shape of an additional term for BI formulation, which models the tangential interaction of the fluid with boundary. A comparison between BI with additional term and DBC is made using the example of horizontal motion of fluid particle over an infinite wall.
Runge-Kutta Discontinuous Galerkin Method Applied to Shallow Water Equations with Flooding and Drying Treatment
Authors: Poussel C. , Ersoy M. , Golay F.
Published: March 2024

This work is devoted to the numerical simulation of Shallow Water Equations involving dry areas and a moving shoreline. The space and time discretization using the Runge-Kutta Discontinuous Galerkin approach is applied to nonlinear hyperbolic Shallow Water Equations. Problems with dry areas are challenging problems for such methods. To counter this issue, special treatment is applied around the shoreline. This work compares two treatments, one based on slope modification and one based on p-adaptation.
Experimental Study on the Spray Characteristics of Internal-Mixing Gas-Liquid Injector under Ambient Pressure
Authors: Qiao W. , Jia B. , Liu X. , Wang S. , Yang L. , Fu Q.
Published: March 2024

To determine the spray characteristics of internal-mixing gas-liquid injector for various operating conditions under ambient pressure, the experimental facilities with backpressure chamber for spraying are established. By means of high-speed camera, Shadow Sizer system and POD method, the effects of gas-liquid momentum ratio, backpressure, pressure drop on the spray characteristics have been investigated in detail. Experimental results demonstrated that as the gas-liquid momentum ratio increases, the spray angle shows an overall increasing trend. The spray angle decreases with increasing backpressure. The spray penetration distance increases as the gas-liquid momentum ratio increases. The penetration distance increases slightly with increasing backpressure. The droplet size decreases and then increases with increasing backpressure. Furthermore, the increase of backpressure can inhibit the unstable oscillation of the spray.
Linear Instability of Mixed Convection in a Vertical Annulus Filled With Porous Medium under LTNE Condition
Authors: Sharma A. , Bera P. , Khan A.
Published: March 2024

The stability of non-isothermal annular parallel flow through a highly permeable porous medium (such as metallic foam) is studied under a local thermal non-equilibrium (LTNE) state. An external pressure gradient and the linear varying temperature of the inner cylinder of the annulus govern the flow. The classical normal mode analysis has been considered to investigate the influence of the different controlling parameters such as Reynolds number (Re), interphase heat transfer coefficient (H), ratio of thermal conductivities (γ) and media permeability (Da) on the instability of the flow. It is found that irrespective of the other parameters, the critical instability boundary decreases sharply with Re in the range of 100 − 2000. An increment in the value of H contributes towards the stability of the basic flow. On the other hand, a destabilizing impact of γ has been observed in the present study.
Experimental Determination of Frequency of Laminar-Boundary Layer Instability Noise of NACA 0012
Authors: Suchý J. , Hyhlík T.
Published: March 2024

This paper presents simple method and new results of experimental investigation of laminar boundary-layer instability noise of an airfoil. The experimental method is based on small electret microphones, which are built in to the surface of the measured airfoil segment in pinholes. The paper discusses evaluation of the experimentally obtained data and presents new results for laminar boundary-layer vortex-shedding tonal sound frequency of NACA 0012. The main attribute of the proposed experimental method is the possibility of its usage in a non-aeroacoustic facility.
Finite Element Approximation of Fluid Structure Interaction Using Taylor-Hood and Scott-Vogelius Elements
Authors: Vacek K. , Sváček P.
Published: March 2024

This paper addresses the problem of fluid flow interacting a vibrating solid cylinder described by one degree of freedom system and with fixed airfoil. The problem is described by the incompressible Navier-Stokes equations written in the arbitrary Eulerian-Lagrangian (ALE) formulation. The ALE mapping is constructed with the use of a pseudo-elastic approach. The flow problem is numerically approximated by the finite element method (FEM). For discretization of the fluid flow, the results obtained by both the Taylor-Hood (TH) element and the Scott-Vogelius (SV) finite element are compared. The TH element satisfies the Babuška-Brezzi inf-sup condition, which guarantees the stability of the scheme. In the case of the SV element the mesh, that is created as a barycentric refinement of regular triangulation, is used to satisfy the Babuška-Brezzi condition. The numerical results for two benchmark problems are shown.
Second Order Semi-Discretization for Unsteady Stokes Flow
Authors: Varnhorn W.
Published: March 2024

We consider a second order implicit time stepping procedure for the unsteady Stokes equations in bounded domains of R3. Using energy estimates we prove optimal convergence properties in a series of Sobolev spaces Hm(G) (m = 0, 1, 2) uniformely in time, provided that the Stokes solution has a high degree of regularity uniformly in time. Here in the case of our second order method the solution of the Stokes equations has to satisfy a certain non-local compatibility condition at the parabolic boundary being virtually uncheckable for given data, which can be satisfied by a special initial construction.
Quasi-Stationary Mathematical Model of Hybrid Rocket Engine Combustion Chamber
Authors: Wardach-Święcicka I. , Kardaś D.
Published: March 2024

This paper presents a quasi-stationary one-dimensional mathematical model of the combustion chamber of a hybrid rocket engine. The model is based on stationary balance equations, considering time-varying input parameters. It makes it possible to quickly estimate the variability of parameters such as pressure, velocity, or temperature of gases inside the combustion chamber during engine operation. In addition, the assumption of a global paraffin oxidation reaction in nitrous oxide allows the determination of the composition of the exhaust gases. The results are consistent with numerical data from other researchers available in the literature.
Quasi-Stationary Mathematical Model of Hybrid Rocket Engine Combustion Chamber
Authors: Yahi F. , Hamnoune Y. , Hellalbi M. A. , Tigrine Z. , Merabet N. , Meziane A. , Bouabdallah A.
Published: March 2024

This work is devoted to the study of the lateral heating effect on a fluid in an inter-cone cavity. This device consists of two coaxial cones having the same apex angle ϕ = 12° giving a constant annular gap so that δ = d/R1max = 0.12 where d = R2max - R1max and containing a Newtonian fluid of constant physical properties as density ρ and kinematic viscosity ν. Both cones are at rest. The study is carried out by CFD program based on the finite volume method. The flow is controlled by the variation of the Grashof number in the range 1000 –5000. The results obtained show the existence of a change in behaviour within the flow as well as the appearance of striations as a function of the variation in the Grashof number.The various obtained results are analysed and compared systematically to the previous results established in other cavities.
Ergonomic RFID tag placement on surgical instruments – a preliminary user study
Authors: Heibeyn Jan , Witte Mark , Billig Sebastian , Schweizer Matthias , Janß Armin , Radermacher Klaus
Published: March 2024

Objectives

RFID tags on surgical instruments allow tracking of individual instruments. However, the tags on the instruments can restrict the handling, potentially increasing patient risks. Previous studies analyzed hand contact areas to identify potential locations for tags. However, the studies did not conduct interaction tests using instruments equipped with RFID tags, potentially neglecting the influence of haptic perception. In addition, previous studies required time-consuming evaluations by clinicians.

Methods

Therefore, the present study aims to verify the previous findings in interaction-centered tests with clinicians using real RFID tags on the instruments. Additionally, we had instrument design experts rate RFID tag positions and examined whether they could predict the clinician’s preferred tag positions.

Results

We found that nearly all RFID tag positions decreased the user satisfaction of clinicians compared to a reference instrument. Compared to previous studies, our study shows that the RFID tag influences the orientations in which an instrument can be comfortably held, which was criticized by clinicians. Instrument design experts could only predict the clinician’s preferred tag positions for some instruments.

Conclusions

Therefore, we recommend investigating further changes to instrument design, for what the “ideal” positions proposed by the clinicians in this study can provide initial pointers.
Analytical performance specifications based on biological variation data – considerations, strengths and limitations
Authors: Sandberg Sverre , Coskun Abdurrahman , Carobene Anna , Fernandez-Calle Pilar , Diaz-Garzon Jorge , Bartlett William A. , Jonker Niels , Galior Kornelia , Gonzales-Lao Elisabet , Moreno-Parro Isabel , Sufrate-Vergara Berta , Webster Craig , Aarsand Aasne K.
Published: March 2024

Analytical performance specifications (APS) are typically established through one of three models: (i) outcome studies, (ii) biological variation (BV), or (iii) state-of-the-art. Presently, The APS can, for most measurands that have a stable concentration, be based on BV. BV based APS, defined for imprecision, bias, total allowable error and allowable measurement uncertainty, are applied to many different processes in the laboratory. When calculating APS, it is important to consider the different APS formulae, for what setting they are to be applied and if they are suitable for the intended purpose. In this opinion paper, we elucidate the background, limitations, strengths, and potential intended applications of the different BV based APS formulas. When using BV data to set APS, it is important to consider that all formulae are contingent on accurate and relevant BV estimates. During the last decade, efficient procedures have been established to obtain reliable BV estimates that are presented in the EFLM biological variation database. The database publishes detailed BV data for numerous measurands, global BV estimates derived from meta-analysis of quality-assured studies of similar study design and automatic calculation of BV based APS.
Improved entropy weight methods and their comparisons in evaluating the high-quality development of Qinghai, China
Authors: Chen Li , Wang Xiangyu , Wang Yuanhui , Gao Peichao
Published: March 2024

“High-quality development” is an important objective for China’s current development projects. For the betterment of the current situation of the underdeveloped regions, high-quality development is necessary. The comprehensive index method is one of the most widely used methods for evaluating high-quality development works, and indicator weighting is its key and at the same time the most controversial step. Among many weighting methods, the entropy weighting method is widely applied due to its easier understandability and use. This article focuses on the problem of weight distortion when the entropy values of indicators are close to 1 and the improvements to this problem. To verify these improvements, this article deduces with mathematical analysis, the underlying assumptions of the problem and evaluates the level of high-quality development in Qinghai Province, which is assumed to be an appropriate example of the underdeveloped regions in western China. Our mathematical deductions demonstrate that these underlying assumptions do not theoretically exist. In addition, both the improved and the original methods have similar performances in practice or, more specifically, have shown an overall upward trend in the level of high-quality development in Qinghai Province. Because the “problem” is extremely stringent and difficult to reproduce, we conclude that further improvements on the entropy weighting method should not be a focus of future research. To address the subjectivity or objectivity issues of weighting, weightless methods may be of use and should be developed.
Increased reactive carboxyl and free alfa-amino groups from fish type I collagen peptides by Alcalase® hydrolysis exhibit higher antibacterial and antioxidant activities
Authors: Yasar Sulhattin , Arslan Hulya Sen , Akgul Kubra
Published: March 2024

This study aimed to generate low molecular weight peptides (LMWP) from fish collagen type I hydrolysed by increasing activity of Alcalase® from 0.0 to 12.0 (AU-A per 100 g) at 55 °C and 7.4 of pH for 3 h 40 min. The results showed that all enzyme activity levels caused 34–55 % reductions in protein recovery, 1.0–3.0 folds’ increase in free α-amino groups and 1.7–3.2 folds’ increase in carboxyl groups. Degree of hydrolysis ranged from 20 to 30 % with increasing enzyme activity. The number average molecular weight significantly reduced from 3200 g/mol in 0.0 AU-A per 100 g enzyme activity to 1151, 1398, 1175, 1040 and 1246 g/mol in 2.4, 4.8, 7.2, 9.6 and 12.0 AU-A per 100 g enzyme activities, respectively. Depending upon enzyme activity level, the produced LMWP with reactive carboxyl and amino end-groups exhibited 2.5- to 4.0-fold increases in antioxidant capacity and 1.0–3.5 log cfu/ml inhibition of four pathogen bacteria. Highest inhibition of 2.5 log cfu/ml in Escherichia coli was obtained from 2.4 AU-A per 100 g enzyme activity and 3.5 log cfu/ml in Listeria monocytogenes from 9.6 and 12.0 AU-A per 100 g enzyme activity levels. Infrared spectroscopy clearly identified reactive end-groups and showed remarkably differences in molar absorptivity of various molecular regions between non-enzyme and enzyme treated collagen type I molecule. A 9.6 and 12.0 AU-A per 100 g enzyme activity levels were found optimally effective to generate LMWP. In conclusion, LMWP exhibited high antioxidant and antibacterial activity due to increased functional reactive end-groups, and these bio-active peptides may have greater potentialities in various food and pharmaceutical applications.
Poroacoustic front propagation under the linearized Eringen–Cattaneo–Christov–Straughan model
Authors: Zampoli Vittorio , Jordan Pedro M.
Published: March 2024

Employing the Laplace transform and its properties, we investigate the evolution of the coupled thermal and fluid-acoustic waveforms that arise in a signaling problem under the Eringen–Cattaneo–Christov–Straughan model of poroacoustic phenomena. Assuming a Heaviside temperature input, we determine the effects of what we term the “Eringen coefficient” by examining the propagation and evolution of the resulting shock and/or acceleration waveforms. Special/limiting cases are also discussed and, in the final section of this Note, possible follow-on studies are suggested.
Conative animal calls in Macha Oromo: function and form
Authors: Andrason Alexander , Mulugeta Onsho , Mazengia Shimelis
Published: March 2024

This article studies the category of conative animal calls (CACs) in a Cushitic variety – Macha Oromo (Ethiopia). The authors analyze the function (pragma-semantics) and form (phonetics and morphology) of 52 CACs collected during fieldwork activities and conclude the following: the category of CACs in Macha Orono largely complies with the prototype of a CAC posited recently in literature. Moreover, Macha Oromo data suggest a few novel generalizations (a close relationship between summonses and onomatopoeias, and between dispersals and motion-inciting/sustaining directionals, as well as a general preference for close I/U vowels) and raise a question regarding the validity of the hierarchy of semantic types of CACs proposed in some studies.
Lactate dehydrogenase to albumin ratio is associated with in-hospital mortality in patients with acute heart failure: Data from the MIMIC-III database
Authors: Xia Xiangjun , Tan Suisai , Zeng Runhong , Ouyang Can , Huang Xiabin
Published: March 2024

The effect of the lactate dehydrogenase to albumin ratio (LAR) on the survival of patients with acute heart failure (AHF) is unclear. We aimed to analyze the impact of LAR on survival in patients with AHF. We retrieved eligible patients for our study from the Monitoring in Intensive Care Database III. For each patient in our study, we gathered clinical data and demographic information. We conducted multivariate logistic regression modeling and smooth curve fitting to assess whether the LAR score could be used as an independent indicator for predicting the prognosis of AHF patients. A total of 2,177 patients were extracted from the database. Survivors had an average age of 69.88, whereas nonsurvivors had an average age of 71.95. The survivor group had a mean LAR ratio of 13.44, and the nonsurvivor group had a value of 17.38. LAR and in-hospital mortality had a nearly linear correlation, according to smooth curve fitting (P < 0.001). According to multivariate logistic regression, the LAR may be an independent risk factor in predicting the prognosis of patients with AHF (odd ratio = 1.09; P < 0.001). The LAR ratio is an independent risk factor associated with increased in-hospital mortality rates in patients with AHF.
Biogenic potassium: sources, method of recovery, and sustainability assessment
Authors: Gahane Dipali , Mandavgane Sachin A.
Published: March 2024

Nutrient management methods based on ecosystems are crucial for providing agricultural nutrient needs while reducing the environmental impact of fertilizer usage. With increasing agricultural production, the global demand for potassium is increasing, with India importing potassium from countries like Canada, USA, Israel, and Russia. Biomass-fired industries generate biomass ash as a residue so management of the resultant ash is important. Agricultural residue ashes contain abundant potassium so could potentially be used for fertilizer application. This review describes different potassium sources and recovery processes, including chemical precipitation, water extraction, solvent extraction, membrane separation, and ionic exchange. Extraction time, temperature, and solid to solvent ratio affect the recovery of potassium from biomass ash. Water extraction is the most commonly used method for potassium recovery from biomass ash. The environmental impact of potassium fertilizer recovered from biomass ash is less than that of mining source of potash. This paper discusses topics not covered in previous reviews, such as different biosources of potassium, latest recovery methods, and life cycle assessment of these methods. The gaps identified in the reports are addressed, and future research opportunities are presented.
Comparison of Cryotherapy Performed With Ice or Gel and Superficial Skin Cooling of Older Women: A Randomized, Crossover, Clinical Trial
Authors: Fachin Kharine dos Santos Maria , de Estéfani Daniela , Marinho e Lima Kelly Mônica , dos Santos Haupenthal Daniela Pacheco , Haupenthal Alessandro
Published: March 2024

Background and Purpose:

Cryotherapy is an affordable and popular treatment of soft tissue injuries, which can reduce inflammation and pain. Studies have specifically addressed young adults and athletes, and these findings have been extended to older adults in clinical practice. Aging is associated with changes in the skin, including collagen degradation, decreased fat layer thickness, and reduced blood flow, which can alter the skin response to stress. Because of age-related changes, there are concerns about the direct use of ice on the skin of older individuals. Skin injuries were also observed after cryotherapy. This study aimed to assess the most effective and safe cryotherapy for superficial skin cooling among older women.

Methods:

Eighteen older women were enrolled in this blinded, randomized, crossover, clinical trial. The mean values (SD) of their age, height, and weight were 70.0 years (6.0), 156.0 cm (9.1), and 72.8 kg (19.5), respectively. The participants underwent cryotherapy using bagged ice, bagged ice plus a wet towel, or gel pack for 20 minutes. The surface temperature of the skin was measured at the end of a 20-minute cryotherapy session using an infrared thermometer. Repeated-measures analysis of variance was conducted to analyze the effect of cryotherapy modalities and time, as well as the interaction between these 2 factors. The secondary outcome was the presence of cryotherapy-induced lesions.

Results and Discussion:

Cryotherapy modalities had significant effects on superficial skin temperature (P = .001). Time points after application also had an effect (P < .0001), and no interaction was observed between cryotherapy modalities and time points (P = .051). Bonferroni post hoc evaluation showed that bagged ice (P = .008) and gel (P = .007) were more effective in decreasing the superficial skin temperature than bagged ice plus wet towel. No difference was observed between bagged ice and gel (P = .32). Three of the 18 patients experienced adverse effects with the gel pack.

Conclusion:

This study of older women found that ice and gel cooled the skin more effectively than ice wrapped in towels. However, the gel pack had some adverse effects. Therefore, bagged ice is recommended for cryotherapy in older women.
Development of Tools for the Direct Measurement of Shear Stress and Shear Strain within a Soil Mass
Authors: Talesnick M. , Omer I. , Ringel M. , Ghafghazi M.
Published: March 2024

This article describes the development of sensing tools designed and applied to the direct measurement of shear stresses and shear strain within a soil mass. The importance in the development of these tools is in their ability to measure shear stresses and shear distortions within soil without any a priori information of the stress and strains applied at the boundaries of the system. These tools may be applied to element testing, testing of physical models, and field applications. The sensors were used in the testing of a sand in a large simple shear apparatus, under both constant height and constant vertical pressure conditions. Testing demonstrated that shear stresses smaller than 0.1 kPa are easily resolved. Shear strains smaller than 10−5 (abs) were reliably measured. Measurement of shear stress and shear distortion within the soil mass allows for direct determination of the shear stiffness of the soil. Shear stiffness measured in this fashion is significantly greater than that determined from the globally measured shear stress and shear strain. The stiffness degradation curve illustrates a constant shear stiffness over the range of 10−5 through 5·10−4.