Analytical Considerations Research Articles

Full-scale monitored wind and response characteristics of a suspension bridge compared with wind tunnel investigations at the design stage

Structural health monitoring of long-span bridges makes it possible to assess the assumptions and considerations in the design stage of the structures through measurements of their structural response and environmental conditions. In wind-resistant design of long-span bridges, the wind-induced dynamic buffeting response is difficult to assess as the uncertainty in the loading and the structural and aerodynamic characteristics is high. In that case, one of the best sources of information is wind tunnel tests, in addition to field measurements and analytical considerations. However, it is unclear if such methods can provide reliable information for the designer since, typically, many uncertainties and assumptions are involved in such a process. Here, we evaluate the scaled full aeroelastic and terrain model tests carried out during the design stage of the Gjemnessund Bridge in Norway through comparisons with full-scale monitoring data spanning five years. The monitoring system and the data are presented along with the wind tunnel study. The results from both campaigns are analyzed and critically discussed, emphasizing implications for the wind-resistant design of long-span bridges.

Structural studies of local environments in high-symmetry quasicrystals

The statistics of how the local environment of a particle looks like, e.g., given by the distribution of nearest neighbor distances or the sizes of Voronoi cells, is important as a starting point for the calculation of many material properties like electronic or photonic band structures. Here we study local environments that occur in quasicrystals with large rotational symmetry. Both with analytical considerations based on geometric arguments and with an analysis of a large number of numerically created patches of high-symmetry quasicrystals we find that the Voronoi area’s distribution reaches a bimodal curve and that in the limit of large rotational symmetries the distribution of nearest neighbor distance converges against a universal curve, where 27.7% of the vertices have their nearest neighbor at a normalized distance equal to 1, while for the other 72.3% the nearest neighbor is at a distance less than 1. Therefore, the statistics of local environments is non-trivial but independent of the specific rotational symmetry. Thus properties that only depend on local environments are expected to be universal for all high-symmetry quasicrystals.

Trapped-particle precession and modes in quasisymmetric stellarators and tokamaks: a near-axis perspective

This paper presents the calculation of the bounce-averaged drift of trapped particles in a near-axis framework for axisymmetric and quasisymmetric magnetic fields that possess up-down and stellarator symmetry, respectively. This analytic consideration provides important insight on the dependence of the bounce-averaged drift on the geometry and stability properties of the field. In particular, we show that although the maximum- $\mathcal {J}$ property is unattainable in quasisymmetric stellarators, one may approach it through increased plasma $\beta$ and triangular shaping, albeit going through a reduced precession scenario with potentially higher particle losses. The description of trapped particles allows us to calculate the available energy of trapped electrons analytically in two asymptotic regimes, providing insight into the behaviour of this measure of turbulence. It is shown that the available energy is intimately related to magnetohydrodynamics (MHD) stability, providing a potential synergy between this measure of gyrokinetic turbulence and MHD stability.

Paediatric reference intervals and curves for haemoglobin and ferritin: protocol for a systematic review and meta-analysis

IntroductionReference intervals and reference curves provide clinicians with a point of reference when evaluating patients’ laboratory test results. In practical applications, the 2.5th and 97.5th percentiles of healthy reference population...

Monitoring reproduction in fish: Assessing the adequacy of ogives and the predicted uncertainty of their L50 estimates for more reliable biological inferences

In fisheries management, the L50 is a commonly-monitored reproductive trait reflecting the sex-specific length (L) at which 50% of the fish are expected to exhibit developing gonads near the spawning period. Although different methods exist to estimate the L50, it is often obtained from a binomial generalized linear model (GLM) fitted with a logit link. To provide reliable parameter estimates for the production of the ogive from which the L50 is obtained, the logit link must be correctly specified, a prerequisite that is not always verified nor true. To identify the most-likely ogive, adequacy tests allowing to detect a lack-of-fit or any link misspecification should ideally be applied to competing binomial models that also consider alternative links, such as the probit and complementary log-log (cloglog). Because multiple estimates are often compared, their uncertainties should also be adequately quantified to detect any potential change, but no consensus exists about the method offering the best coverage probability. Here, we used a large-scale dataset of 23,681 walleye (Sander vitreus) females sampled in 90 harvested populations over two decades in Québec, Canada, to first estimate the L50 uncertainty under different simulation scenarios to identify the most accurate method regarding nominal coverage. Then, of 46 populations sampled in two different surveys, we assessed which link provided the best adequate estimation for each survey-specific L50 and used associated 84% CIs to determine if a change occurred based on whether they overlapped. The influence of gonad data characteristics on L50 uncertainty was also examined before assessing between-survey L50 variation with competing GLMs as an alternative approach. The analysis of the simulated data indicated that the Monte Carlo approach with bias-corrected and accelerated (BCa) interval offered the best coverage probability. The empirical analyses revealed that the probit was the most often adequate link to estimate the L50, followed by the cloglog, whereas the logit ranked last. When controlling for sample size, the level of L50 uncertainty increased with the percentage of overlap in length between walleye females with (1) and without (0) developing gonads, whereas it progressively decreased as the percentage of 1’s in the sample increased to then inversed, indicating that more balanced binary data yielded less L50 uncertainty. All analyses revealed that for a “true” or estimated effect size of ≤ 10%, the survey-specific 84% CIs often overlapped despite statistical support for a difference found in the best-supported GLM comparing both surveys. Overall, our study indicates that many analytical considerations, from gonad data structure characteristics, model adequacy assessment, up to how the L50 uncertainty is quantified and compared, need to be accounted for to achieve more reliable statistical inferences regarding the observed variation in this reproductive trait.

Wind-driven salinity tongue migration in the Gulf of Finland according to NEMO and ERA5 reanalyses

Two hypothesis that can be responsible for the wind-driven migration of the salinity tongue in the bottom layer of the Gulf of Finland (GoF) are tested based on the NEMO and ERA5 reanalyses. The first hypothesis authored by Krauss and Brügge (1991) implies along-channel wind developing upwelling and downwelling jet-like currents in the wind direction at opposite lateral boundaries of the channel, and a compensatory countercurrent in the deep layer (the so-called coastal jet hypothesis). The second hypothesis implies the cross-channel wind developing the along-channel Ekman transport in the upper layer, and a countercurrent in the deep layer (so-called Ekman transport hypothesis). The salinity tongue migration velocity along the GoF thalweg as estimated from the NEMO output is found to be extremely correlated with the along-thalweg projection of the wind stress calculated from the ERA5 output. This is a convincing evidence in favor of the coastal jet hypothesis as opposed to the Ekman transport hypothesis to correctly describe the mechanism of the wind-driven migration of salinity tongue in GoF. Based on a theory of coastal upwelling/downwelling in a two-layer fluid, some analytical considerations and related empirical estimates are presented to explain the prevailing coastal jet mechanism in GoF.

Understanding Individual Subject Differences through Large Behavioral Datasets: Analytical and Statistical Considerations.

A core feature of behavior analysis is the single-subject design, in which each subject serves as its own control. This approach is powerful for identifying manipulations that are causal to behavioral changes but often fails to account for individual differences, particularly when coupled with a small sample size. It is more common for other subfields of psychology to use larger-N approaches; however, these designs also often fail to account for the individual by focusing on aggregate-level data only. Moving forward, it is important to study individual differences to identify subgroups of the population that may respond differently to interventions and to improve the generalizability and reproducibility of behavioral science. We propose that large-N datasets should be used in behavior analysis to better understand individual subject variability. First, we describe how individual differences have been historically treated and then outline practical reasons to study individual subject variability. Then, we describe various methods for analyzing large-N datasets while accounting for the individual, including correlational analyses, machine learning, mixed-effects models, clustering, and simulation. We provide relevant examples of these techniques from published behavioral literature and from a publicly available dataset compiled from five different rat experiments, which illustrates both group-level effects and heterogeneity across individual subjects. We encourage other behavior analysts to make use of the substantial advancements in online data sharing to compile large-N datasets and use statistical approaches to explore individual differences.

Theory of Hybrid Microwave–Photonic Quantum Devices

AbstractThe Maxwell–Lindblad transmission line (MLT) equations are introduced as a model for hybrid photonic and microwave‐electronic quantum devices. The hybrid concept has long enabled high‐bandwidth photodetectors and modulators by using waveguide structures supporting microwave–optical co‐propagation. Extending this technique to quantum‐engineered lasers provides a route for greatly improved short‐pulse and frequency comb operation, as impressively demonstrated for quantum cascade lasers. Even more, the self‐organized formation of coupled microwave and optical oscillation patterns has recently enabled photonics‐based ultralow‐noise microwave generation. The MLT model provides a suitable theoretical description for hybrid quantum devices by combining optical and microwave propagation equations with a Lindblad‐type approach for the quantum active region dynamics. A stable numerical scheme is presented, enabling realistic device simulations in excellent agreement with experimental data. Based on numerical results and analytical considerations, it is demonstrated that the functionality of the investigated hybrid quantum devices does not only rely on local coupling effects, but rather benefits from microwave‐optical co‐propagation, settling an ongoing debate. The MLT equations provide the basis for systematic device development and extension of the concept to other quantum‐engineered hybrid devices based on, for example, quantum dot or interband cascade structures, as well as for simplified analytical models providing additional intuitive insight.

Artistic Energy of the Performers in the Mirror of Their Repertoire Preferences

"The problem field of this article consists of learning the essence of the phenomenon of artistic energy and understanding the performing repertoire as one of the ways of its objectification. Each component of the specified subject of study has its own problem, which is also subject to development. The choice of the proposed subject of scientific cognition is motivated by the desire to understand the phenomenon of the subject of performing interpretative activity. An important factor in its study is the disclosure of the artistic properties of the pianist’s personality, which contributes to the establishment of contact between the concert performer and the listening audience. A little-studied aspect of the analytical consideration of artistic energy remains the question of methods of its objectification, which is the subject of the proposed article. It is stipulated by the perspective of the direction of modern musicology related to the scientific development of the performing repertoire. The location of the selected research subject at the intersection of the named scientific contexts is designed to understand the various properties of the subject of the performing activity as a component of a single system. Therefore, the purpose of this article is to substantiate the idea of the performers’ repertoire preferences as a reflection of their artistic energy. Keywords: pianist-performer, artistic energy, piano repertoire, interpretation, performing style."

The geography of sustainability transition and materiality: grid-tied solar photovoltaic technology in Sri Lanka

ABSTRACT The geography of sustainability transition (GeoST) literature views solar photovoltaic (PV) as an off-the-shelf, footloose, absolute technology for bringing about a technological shift in locations with high solar irradiation. Herein, I argue against viewing solar technology in these ways, highlighting that consideration should also be given to the configuration of solar PV that suits the contextual conditions. To this end, I offer empirical evidence for the need to approach solar PV diffusion through a relational perspective. Accordingly, different solar PV technology formats may become necessary for its successful implementation in diverse contexts. Supportive empirical evidence comes from Sri Lanka’s large-scale grid-tied solar PV implementation. I conclude the paper with an analytical consideration of the influence of material factors as being as important within GeoST as that of intangible factors, and that technological shift should be pursued within a location’s contextual relational materiality.

(Pre)analytical considerations concerning the analysis of synovial calprotectin.

Several studies have demonstrated that synovial calprotectin is a highly accurate biomarker in diagnosing periprosthetic joint infections (PJI). Assuring reliability is of great importance and coincides with adequate preanalytical handling. This study focuses on potentially interfering factors. To assess the stability of synovial calprotectin, the effect of time, storage temperature, EDTA, freeze-thaw cycles, viscosity, and blood and lipid contamination was investigated. In the blood and lipid contamination experiments, hemolyzed and non-hemolyzed blood, homogenized adipose tissue, intralipid and chylomicrons were added. The effect of viscosity was investigated using freeze-thaw cycles, enzymatic pretreatment and sonification. No effect on synovial calprotectin levels was observed in synovial samples kept at room temperature compared to samples kept at 4 °C for up to seven days of storage. Freeze-thaw cycles did not result in significantly different calprotectin levels, although samples without EDTA resulted in higher recoveries after 1 and 2 freeze-thaw cycles. Blood and lipid contamination did not interfere with accurate synovial calprotectin analysis. Sample pretreatment to reduce sample viscosity by pretreating samples with DNAse and/or hyaluronidase did not influence calprotectin analysis. Sonification, however, resulted in increased calprotectin values. Synovial calprotectin is a stable biomarker and its analysis is not easily influenced by potential interfering factors.

Interval traffic analysis of multichannel queuing systems

The passage of streaming video traffic through the backbone switch of the communication node is considered. The features of video traffic, which has a pronounced burst character, are analyzed. The influence of the characteristics of such flows on the sizes of queues in the nodes of telecommunication networks is studied. The results of analytical consideration and simulation modeling are presented. The generalized Khinchin-Pollachek formula is considered and for group flows a linear dependence of the numerator of this formula on the load factor is shown. It is shown that, in contrast to Poisson flows, the queue sizes in multichannel queuing systems with video traffic flows practically do not decrease with an increase in the number of channels.

Untargeted hair lipidomics: comprehensive evaluation of the hair-specific lipid signature and considerations for retrospective analysis.

Lipidomics investigates the composition and function of lipids, typically employing blood or tissue samples as the primary study matrices. Hair has recently emerged as a potential complementary sample type to identify biomarkers in early disease stages and retrospectively document an individual's metabolic status due to its long detection window of up to several months prior to the time of sampling. However, the limited coverage of lipid profiling presented in previous studies has hindered its exploitation. This study aimed to evaluate the lipid coverage of hair using an untargeted liquid chromatography-high-resolution mass spectrometry lipidomics platform. Two distinct three-step exhaustive extraction experiments were performed using a hair metabolomics one-phase extraction technique that has been recently optimized, and the two-phase Folch extraction method which is recognized as the gold standard for lipid extraction in biological matrices. The applied lipidomics workflow improved hair lipid coverage, as only 99 species could be annotated using the one-phase extraction method, while 297 lipid species across six categories were annotated with the Folch method. Several lipids in hair were reported for the first time, including N-acyl amino acids, diradylglycerols, and coenzyme Q10. The study suggests that hair lipids are not solely derived from de novo synthesis in hair, but are also incorporated from sebum and blood, making hair a valuable matrix for clinical, forensic, and dermatological research. The improved understanding of the lipid composition and analytical considerations for retrospective analysis offers valuable insights to contextualize untargeted hair lipidomic analysis and facilitate the use of hair in translational studies.

Філософія трансцендентального опору (христоцентрична битва України з лукавим)

The proposed study examines the antithetical worldview of the Ukrainian and Moscow-imperial mentalities, which is manifested in the “Diaries” of Sergei Efremov and Korniy Chukovsky and other objectively unbiased sources. In particular, a number of moral and ethical, socio-psychological constants found in various life situations by the authors of these sources are studied. Forms of their presence in diary prose as documentary evidence of the era of direct participants in the events are outlined and analyzed. It is determined that the “Diaries” of S. Efremov and Korniy Chukovsky, as well as “The Cursed Days” by I. Bunin and other sources, not only constitute a still unexplored basis for understanding the era, but also have significant potential for modern and future comparative philosophical and Ukrainian studies in the specified problem-thematic discourse. In view of this, a number of conceptual parallels were drawn between the worldviews of artists-thinkers who created in Russian, but whose worldview was in the value-semantic paradigm of Ukrainian Christocentric thinking. Based on analytical considerations, it was determined that the worldview concepts of the Ukrainian Christocentric-Christ-inheriting farming worldview are completely opposite to the worldview and the resulting aggressive-aggressive, cunning non-Asian custom, the basis of which, according to its representatives, is cynicism.

Estimating the time of human decomposition based on skeletal muscle biopsy samples utilizing an untargeted LC-MS/MS-based proteomics approach.

Accurate estimation of the postmortem interval (PMI) is crucial in forensic medico-legal investigations to understand case circumstances (e.g. narrowing down list of missing persons or include/exclude suspects). Due to the complex decomposition chemistry, estimation of PMI remains challenging and currently often relies on the subjective visual assessment of gross morphological/taphonomic changes of a body during decomposition or entomological data. The aim of the current study was to investigate the human decomposition process up to 3months after death and propose novel time-dependent biomarkers (peptide ratios) for the estimation of decomposition time. An untargeted liquid chromatography tandem mass spectrometry-based bottom-up proteomics workflow (ion mobility separated) was utilized to analyse skeletal muscle, collected repeatedly from nine body donors decomposing in an open eucalypt woodland environment in Australia. Additionally, general analytical considerations for large-scale proteomics studies for PMI determination are raised and discussed. Multiple peptide ratios (human origin) were successfully proposed (subgroups < 200 accumulated degree days (ADD), < 655 ADD and < 1535 ADD) as a first step towards generalised, objective biochemical estimation of decomposition time. Furthermore, peptide ratios for donor-specific intrinsic factors (sex and body mass) were found. Search of peptide data against a bacterial database did not yield any results most likely due to the low abundance of bacterial proteins within the collected human biopsy samples. For comprehensive time-dependent modelling, increased donor number would be necessary along with targeted confirmation of proposed peptides. Overall, the presented results provide valuable information that aid in the understanding and estimation of the human decomposition processes.

Geographies of big water infrastructure: Contemporary insights and future research opportunities

AbstractLargescale “big” water infrastructure is once again at the forefront of the global developmentalist agenda and is receiving attendant scholarly attention. Given this parallel growth, now is time to take stock of current scholarly contributions and explore opportunities for future research. In this paper, I review recent developments and insights gained from research on big water infrastructure, and water infrastructure studies, generally, to highlight six key threads of current scholarship. These include the production of big water infrastructure as: (1) a temporal process embedded in colonialism and ecological modernization; (2) infused with infrastructural knowledges, practices and subjectivities; (3) a spatial‐geopolitical process; (4) subject to infrastructural and environmental material characteristics and capacities; (5) producing uneven development and enabling accumulation by dispossession; and (6) a contested process of differentiated socio‐material resistance. In reviewing this literature, I argue that these six research strands form key analytic considerations that could be employed by others studying the nexus between water development, political ecological change, and infrastructure. Before concluding, in the final section of the paper I present additional and ongoing future research directions including big water infrastructure as it intersects with socially differentiated human intimacy and embodiment, indigenous and racialized forms of dispossession, and financialization.

Textile Impressions in California Archaeology: Analytical Considerations and Research Potential

ABSTRACT In the absence of exceptional organic preservation, data on ancient textile industries can be recovered from intentional and accidental negative impressions of woven products left in media that are plastic or pliable initially, but which harden later. However, detailed studies of such textile impressions remain uncommon across the western United States. In California, where surviving plant-based organic artifacts are generally quite rare, impressions in asphaltum (bitumen) provide a means of acquiring data on textile crafts that are increasingly recognized for their potential to contribute to anthropological research questions. Here we review analytical considerations attendant to impressions analysis and explore the underappreciated research potential of textile impressions. Drawing on recent results from the detailed analysis of assemblages of textile impressions in asphaltum from two sites in California, we offer methodological suggestions and review the salient interpretive inferences from these studies that stand to enhance the research potential of similar assemblages.

The image of the grove as a means of expressing the author 's axiological concept in the lyrics of Z. Dudina

This research is connected with the analytical consideration of the system of poetic images of a natural philosophical orientation in modern Mari philosophical lyrics. The aim of the work is to identify the ethnocentric semantic components of the mythopoetic image of the grove in the lyrics of Zoya Dudina and the ways of their artistic embodiment. The research material was the poems included in her collection "Kuanyshym, kuem &amp;#1255;ndal ..." (She was delighted, hugging a birch ...) (2012). The methodology of the research is determined by the structural and semantic analysis of lyrical texts, which allows to identify and describe the main structural components of the poetic image, as well as to understand their interrelationships and semantic organization at the level of the author's axiology. In the article, the author of the study proved that in the lyrics of the Mari poet Zoya Dudina, the multifaceted image of the Mari grove is recreated. In particular, it is presented as part of the divine world, often concretized and given in the form of a sacred tree. The central place in the image of the grove is assigned by the author to the ethnically significant and sacred content and mythopoetics, which does not limit him in the expression of individual creative aspirations, in the assertion of universal values. The grove for the lyrical heroine Zoya Dudina is a symbol of hope, spiritual and moral support, salvation of the soul, as well as the preservation of the Mari people.

Bridging the diversity gap: Analytical and study design considerations for improving the accuracy of trans-ancestry genetic prediction.

Genetic prediction of common complex disease risk is an essential component of precision medicine. Currently, genome-wide association studies (GWASs) are mostly composed of European-ancestry samples and resulting polygenic scores (PGSs) have been shown to poorly transfer to other ancestries partly due to heterogeneity of allelic effects between populations. Fixed-effects (FETA) and random-effects (RETA) trans-ancestry meta-analyses do not model such ancestry-related heterogeneity, while ancestry-specific (AS) scores may suffer from low power due to low sample sizes. In contrast, trans-ancestry meta-regression (TAMR) builds ancestry-aware PGS that account for more complex trans-ancestry architectures. Here, we examine the predictive performance of these four PGSs under multiple genetic architectures and ancestry configurations. We show that the predictive performance of FETA and RETA is strongly affected by cross-ancestry genetic heterogeneity, while AS PGS performance decreases in under-represented target populations. TAMR PGS is also impacted by heterogeneity but maintains good prediction performance in most situations, especially in ancestry-diverse scenarios. In simulations of human complex traits, TAMR scores currently explain 25% more phenotypic variance than AS in triglyceride levels and 33% more phenotypic variance than FETA in type 2 diabetes in most non-European populations. Importantly, a high proportion of non-European-ancestry individuals is needed to reach prediction levels that are comparable in those populations to the one observed in European-ancestry studies. Our results highlight the need to rebalance the ancestral composition of GWAS to enable accurate prediction in non-European-ancestry groups, and demonstrate the relevance of meta-regression approaches for compensating some of the current population biases in GWAS.

Neural networks meet hyperelasticity: A guide to enforcing physics

In the present work, a hyperelastic constitutive model based on neural networks is proposed which fulfills all common constitutive conditions by construction, and in particular, is applicable to compressible material behavior. Using different sets of invariants as inputs, a hyperelastic potential is formulated as a convex neural network, thus fulfilling symmetry of the stress tensor, objectivity, material symmetry, polyconvexity, and thermodynamic consistency. In addition, a physically sensible stress behavior of the model is ensured by using analytical growth terms, as well as normalization terms which ensure the undeformed state to be stress free and with zero energy. In particular, polyconvex, invariant-based stress normalization terms are formulated for both isotropic and transversely isotropic material behavior. By fulfilling all of these conditions in an exact way, the proposed physics-augmented model combines a sound mechanical basis with the extraordinary flexibility that neural networks offer. Thus, it harmonizes the theory of hyperelasticity developed in the last decades with the up-to-date techniques of machine learning. Furthermore, the non-negativity of the hyperelastic neural network-based potentials is numerically examined by sampling the space of admissible deformations states, which, to the best of the authors’ knowledge, is the only possibility for the considered nonlinear compressible models. For the isotropic neural network model, the sampling space required for that is reduced by analytical considerations. In addition, a proof for the non-negativity of the compressible Neo-Hooke potential is presented. The applicability of the model is demonstrated by calibrating it on data generated with analytical potentials, which is followed by an application of the model to finite element simulations. In addition, an adaption of the model to noisy data is shown and its extrapolation capability is compared to models with reduced physical background. Within all numerical examples, excellent and physically meaningful predictions have been achieved with the proposed physics-augmented neural network.