Orders Of Magnitude Research Articles

Local polar order controls mechanical stress and triggers layer formation in Myxococcus xanthus colonies

Colonies of the social bacterium Myxococcus xanthus go through a morphological transition from a thin colony of cells to three-dimensional droplet-like fruiting bodies as a strategy to survive starvation. The biological pathways that control the decision to form a fruiting body have been studied extensively. However, the mechanical events that trigger the creation of multiple cell layers and give rise to droplet formation remain poorly understood. By measuring cell orientation, velocity, polarity, and force with cell-scale resolution, we reveal a stochastic local polar order in addition to the more obvious nematic order. Average cell velocity and active force at topological defects agree with predictions from active nematic theory, but their fluctuations are substantially larger than the mean due to polar active forces generated by the self-propelled rod-shaped cells. We find that M. xanthus cells adjust their reversal frequency to tune the magnitude of this local polar order, which in turn controls the mechanical stresses and triggers layer formation in the colonies.

Transcriptomic response of an algal species (raphidocelis subcapitata) exposed to 22 per- and polyfluoroalkyl substances.

Per- and polyfluoroalkyl substances (PFAS) are a large class of chemicals of concern for both human and environmental health because of their ubiquitous presence in the environment, persistence, and potential toxicological effects. Despite this, ecological hazard data are limited to a small number of PFAS even though there are over 4000 identified PFAS. Traditional toxicity testing will likely be inadequate to generate necessary hazard information for risk assessment. Therefore, the present study investigated the utility of using transcriptomic points of departure (tPODs) for informing PFAS algal toxicity. Raphidocelis subcapitata, a freshwater green algal species, were exposed for 24 hours in 96 well microplates to multiple concentrations of 22 different PFAS. Following exposure, RNA was extracted, and the transcriptome was evaluated by RNA sequencing followed by concentration response modeling to determine a tPOD for each PFAS. PFAS tPODs, based upon measured concentrations, ranged from 0.9 µg/L for perfluorotridecanoic acid to 1 mg/L for perfluorononanoic acid. These values derived from R. subcapitata exposures were compared to published hazard benchmarks from other taxa (larval fathead minnow and Daphnia magna) and in vitro data. While R. subcapitata was generally more sensitive to the tested PFAS than previously tested taxa and in vitro assays, the algal tPODs were, on average, three orders magnitude greater than the maximum concentrations of PFAS detected in Great Lakes tributaries. This high throughput transcriptomics assay with algae is a promising new approach method for an ecologically relevant, tiered hazard evaluation strategy.

Topography-guided, patterned, customized corneal crosslinking for non-invasive astigmatism correction.

To propose and evaluate a novel, non-invasive approach for enduring corneal astigmatism correction based on topography-guided, patterned, customized riboflavin-ultraviolet A corneal collagen crosslinking (CXL). Astigmatism was modelled on both eyes of rabbits. A randomly selected eye of each rabbit was treated by the proposed CXL procedure with another eye as control. The proposed procedure was performed by a self-built intelligent platform through delivering ultraviolet A lattice in a refined and patterned manner, based on pre-operative corneal topography. The long-term effectiveness, stability, and safety were investigated for 180 days, with topographic measurements, anterior segment optical coherence tomography (AS-OCT), and in vivo corneal confocal microscopy (IVCM). Spatially selective demarcation lines in AS-OCT images and trabecular patterned hyperdense structure with abundant needle-like processes in IVCM images were detected in the CXL eyes, revealing spatially selective crosslinking. Reductions of astigmatic magnitude (in the steep axis: 0.46 ± 0.28 vs. 2.15 ± 0.58 dioptres, P < 0.001) and high order aberration (0.38 ± 0.18 vs. 0.59 ± 0.19, P = 0.009) with increase of visual strehl ratio (0.21 ± 0.06 vs. 0.13 ± 0.03, P < 0.001) were found in the CXL eyes after CXL and maintained for 180 days, compared to inconspicuous changes in the control eyes. No obvious opacity and inflammation were observed in the CXL eyes, and transient loss of endothelial cells in the treated area was recovered in the subsequent visit. The proposed novel, non-invasive approach safely fulfilled corneal astigmatism correction with visual quality improvement as well as a decrease in high-order aberration.

Co-assemblies of Silver Nanoclusters and Fullerenols With Enhanced Third-Order Nonlinear Optical Response.

Exploring potential third-order nonlinear optical (NLO) materials attracts ever-increasing attention. Given that the atomically precise and rich adjustable structural features of silver nanoclusters (Ag NCs), as well as the unique π-electron conjugated system of carbon-based nanomaterials, a supramolecular co-assembly amplification strategy to enhance the luminescent intensity and NLO performance of the hybrids of the two components, are constructed and the relationship between structures and optical properties are investigated. By combining water soluble Ag NCs [(NH4)6[Ag6(mna)6] (H2mna = 2-mercaptonicotinic acid, abbreviated to Ag6─NCs hereafter) containing uncoordinated carboxyl groups with water-soluble fullerene derivatives modified with multiple hydroxyl groups (fullerenols, C60─OH), the π-electron delocalization is expanded owing to non-covalent hydrogen bonding effect between Ag6─NCs and C60─OH, which provides a feasible basis for realizing the NLO response. Then, the co-assemblies are doped into a PMMA matrix to prepare composite film and its NLO properties are evaluated by Z-scan technique. Remarkably, the effective nonlinear absorption coefficients β is of two orders magnitude higher than those of the Ag6─NCs assemblies at the absence of C60─OH. This work showcases a new approach for amplifying NLO responses which greatly facilitates the development of integrated photonic devices.

The SAMgram: a novel local enhancement and targeted extraction strategy for weak bearing fault characteristics

Envelope analysis is one of the most commonly used methods in rolling bearing fault diagnosis. However, when a signal contains heavy noise, even if an appropriate frequency band is selected, the fault information can still be overwhelmed. Unlike traditional use of spectral amplitude modulation, a novel SAMgram is proposed in this article for the enhancement and extraction of weak bearing fault characteristics in a signal, where local spectral amplitude modulation (LSAM) is performed to highlight bearing fault components and improve the proportion of fault information. Meanwhile, a targeted indicator called normalized harmonic kurtosis is proposed to select an optimal modified filtered signal automatically by quantifying repetitive transient characteristics. To extend LSAM to practical applications, two spectrum segmentation strategies are provided based on scanning spectrum and trend component, named the scanning SAMgram and adaptive SAMgram, respectively, which aim at determining the optimal modified filtered signal for demodulation by searching for the combinations of frequency bands and magnitude orders. A simulated signal of bearing compound faults and experimental signals of bearing outer ring and inner ring faults indicate that the proposed method can not only select a frequency band related to bearing defect to eliminate interference of invalid components but also highlight fault characteristics in the selected frequency band and weaken the disturbance of noise, which is superior over traditional envelope analysis-based methods and more applicable for fault diagnosis of rolling bearings under complex environments.

Advanced low-power filter architecture for biomedical signals with adaptive tuning.

This paper presents a low-power, second-order composite source-follower-based filter architecture optimized for biomedical signal processing, particularly ECG and EEG applications. Source-follower-based filters are recommended in the literature for high-frequency applications due to their lower power consumption when compared to filters with alternative topologies. However, they are not suitable for biomedical applications requiring low cutoff frequencies as they are designed to operate in the saturation region. The major contribution in this work are the filter is made to operate in the weak inversion zone to reduce the area needed for the capacitor and the amount of power dissipated. Process variation is one of the major issues in the weak inversion regime. To overcome this, a unique method of compensating against fluctuations in process, voltage, and temperature is put forth based on magnitude comparison is another contribution. Key findings from post-layout simulations and experimental measurements demonstrate that the filter achieves a tunable cutoff frequency range of 0.5 Hz to 150 Hz, with a total power dissipation of only 6nW at 150 Hz. The design occupies a compact silicon area of 0.065 mm2 and offers a dynamic range of 75 dB. The measured results indicate that for a 300 mVpp signal swing, the top bound on THD is -40 dB. The filter's robustness against process, voltage, and temperature variations is validated through on-chip tuning using a current steering DAC, ensuring stable performance across different operating conditions. These results make the proposed filter a promising candidate for low-power biomedical devices. The recommended filter is developed and implemented using UMC-0.18μm CMOS technology with a 1.0V supply, and the IC is tapped out using an MPW run of Euro practice IC services.

Lack of integrated number sense among college students: Evidence from rational number cross-notation comparison.

Growing evidence highlights the predictive power of cross-notation magnitude comparison (e.g., 2/5 vs. 0.25) for math outcomes, but whether these relations persist into adulthood and the underlying mechanisms remain unknown. Across two studies during the 2021-2022 academic year, we investigated undergraduates' cross-notation and within-notation comparison skills given equivalent fractions, decimals, and percentages (Study 1, N = 220 and Study 2, N = 183). We found participants did not perceive equivalent rational numbers equivalently. Cluster analyses revealed that approximately one-quarter of undergraduates exhibited a bias to select percentages as larger in cross-notation comparisons. Compared with the other cluster of undergraduates who showed little-to-no bias, the percentages-are-larger bias cluster performed worse on fraction number line estimation and fraction arithmetic (exact and approximate), as well as reporting lower Scholastic Aptitude Test/American College Test (SAT/ACT) scores. Hierarchical linear regression analyses demonstrated that cross-notation comparison accuracy accounted for variance in SAT/ACT beyond within-notation accuracy. Mediation analyses were consistent with a potential mechanism: Stronger cross-notation knowledge equips individuals to evaluate the reasonableness of fraction arithmetic solutions. Together, these results suggest the importance of an integrated understanding of rational number notations, which may not be fully assessed by within-notation measures alone. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

Response of Plant Community Characteristics and Soil Factors to Topographic Variations in Alpine Grasslands.

Topography has an important influence on plant-soil relationships. However, research on plant-soil relationships in alpine grassland at the slope aspect and slope position scales is currently inadequate. In this paper, based on the topographic and geomorphological characteristics of the study area, alpine grassland with typical slope aspect and slope position conditions was selected as the research object. Through field investigations and laboratory research to reveal how the characteristics of the alpine grassland plant community and soil factors respond to changes in topography. The results show: Slope aspect and slope position changes significantly affect alpine grassland plant communities and soil properties. In terms of the dominant species in plant communities, the sunny slopes were dominated by Poaceae and the shady slopes were dominated by Polygonaceae. Plant community characterization variables showed a decreasing trend from shady to sunny slopes and bottom to top. The soil factors showed significant differences among the six types of topography (p < 0.05), and the magnitude order in different slope aspects and positions was basically shady slope > sunny slope and bottom > middle and top. Correlation analysis showed that there were good correlations between soil organic carbon (SOC), soil water content (SWC), total nitrogen (TN), pH, and plant community characteristics in alpine grassland. In addition, redundancy analyses (RDA) indicated that the divergence in plant community characteristics was primarily driven by the change difference in SOC along topographic gradients. Our findings may provide a scientific basis for the restoration and utilization of alpine grassland vegetation and the evaluation of the ecological environment in this region.

Magnitude-space representations in the n-back task: Long-term representations of magnitudes alter the working memory performance.

Prior research has predominantly examined the role of working memory (WM) in tasks involving numerical information and spatial properties, such as memorizing number sequences and performing parity judgment and magnitude comparison. In contrast to focusing solely on the effect of WM on number judgment tasks, our study investigates how magnitude-space associations affect WM task performance, emphasizing long-term representations, specifically the concept of mental number line (MNL) compatibility (small items on the left, large items on the right) in long-term memory (LTM). Moving from the idea of representations within LTM contribute to the functioning of WM during task execution, we explore the effects of congruent, incongruent, and negative congruent numerical and non-numerical magnitude-space associations on magnitude-based 1-back (low WM load) and 2-back (high WM load) tasks. MNL compatible n-back and test items are congruent, MNL compatible n-back and MNL incompatible (small on the right, large on the left) test items (or vice versa) are incongruent, and MNL incompatible n-back and test items are considered negative congruent. Because negative congruent and incongruent representations may not activate existing representations in LTM, as congruent representations, we expected worse WM performance in negative congruent and incongruent trials than in congruent trials. Results reveal that congruent and incongruent representations elicit more accurate and rapid responses than negative congruents, suggesting that congruent and incongruent representations contribute to task execution. Additionally, we observe a size effect for small numerical magnitudes and a reverse size effect for large physical magnitudes, pointing towards the coactivation of LTM and WM in magnitude-space relations.

Identification of ram pressure stripping features in galaxies using citizen science

Our aim is to explore the efficacy of citizen science classifications in identifying ram pressure stripped galaxies, and use this to aid in motivating new potential samples of ram pressure stripped candidates. We compiled a sample of over 200 known ram pressure stripped galaxies from the existing literature, with morphological classifications obtained from Galaxy Zoo. We compared these galaxies with magnitude and redshift-matched comparison cluster and field galaxies. Additionally, we created a sample of SDSS cluster galaxies, with morphological classifications similar to known ram pressure stripped galaxies, and compared the fraction of potential new RPS candidates against control samples. We find that ram pressure stripped galaxies exhibit a higher proportion of `odd' and `irregular' morphological classifications compared to field and cluster comparison samples. This trend is particularly pronounced in galaxies displaying strong optical ram pressure stripping features, but absent from galaxies with only radio tails. We find that SDSS galaxies with Galaxy Zoo classifications consistent with the known RPS galaxies have a higher fraction of visible ram pressure stripping features ($19&lt;!PCT!&gt;$) compared with other cluster galaxies ($12&lt;!PCT!&gt;$) when classified by experts. We identify 101 new ram pressure stripping candidate galaxies through these expert classifications. We demonstrate that indirect morphological classifications from citizen science projects can increase the efficiency with which new stripping candidates are found. Projects such as Galaxy Zoo can aid in the identification of ram pressure stripped galaxies that are key to understanding galaxy evolution in clusters.

Early numerical skills and mathematical domains in autistic students in primary school.

It is crucial to provide a quality educational response to the needs of autistic children across various mathematical domains. However, there is no consensus on which of the early skills have the greatest predictive effect in the short and long term within these domains. Therefore, this research aimed to a) compare early numerical skills and mathematics domains, and 2) analyze the predictive value of early numerical skills into mathematics domains. Forty-two children (twenty-one autistic children and twenty-one non-autistic children) aged 6-12 years participated in the study. Three areas were evaluated through different tasks: 1) control tasks: reading, impulse control and manual speed, 2) early numerical skills: counting, verbal subitizing, magnitude comparison and estimation, and 3) mathematical domains: arithmetic calculation and arithmetic word problems. Significant differences were found in subitizing and estimation tasks. Both groups showed similar mathematical skills in arithmetic calculation and arithmetic word problems. For autistic students, several non-symbolic tasks predict performance in mathematical domains, whereas for non-autistic students, symbolic tasks were predictors. Although mathematics does not seem to be an area of concern for autistic children, future studies should explore early numerical and mathematical domains in children with cognitive support needs through longitudinal research.

Systematic studies of odd-even staggering in isotopic cross sections with new difference formulas* *Supported by the National Natural Science Foundation of China (12005314), the SYSU 100 Top Talents Program, and the Major Project of Basic and Applied Basic Research of Guangdong Province, China (2021B0301030006)

Although a 3rd-order difference formula has often been employed to investigate the odd-even staggering (OES) in experimental cross sections, other formulas can also be very useful. In this work, three formulas, the 2nd, 4th, and 5th-order difference formulas, are proposed for systematic OES studies. These new difference formulas with different orders are applied to extract the OES magnitudes in extensive accurate cross sections measured in different fragmentation and spallation reaction systems over a broad energy range. According to comparisons of these (2nd, 4th, and 5th-order) OES magnitudes derived from different reaction systems, they almost do not rely on the projectile-target combinations or the projectile energy. A similar universality was observed for the 3rd-order OES magnitudes obtained from various reaction systems in our previous studies of the 3rd-order OES. The weighted average values of the 2nd, 4th, and 5th-order OES magnitudes extracted from different experimental datasets are recommended as the 2nd, 4th, and 5th-order OES evaluations, respectively. Finally, comparisons of these (new) 2nd, 4th, 5th, and previous 3rd-order OES evaluations support that these OES evaluations with different orders are consistent and that all the difference formulas with different orders are applicable to OES studies.

Number and domain both affect the relation between executive function and mathematics achievement: A study of children's executive function with and without numbers.

Magnitude processing and executive functions (EFs) have emerged as robust predictors of mathematics achievement. However, the nature of these associations is still unclear. For example, it is uncertain if EFs applied in the context of domain-specific mathematical cognition (i.e., EFs applied while processing numbers) are more closely related to mathematics achievement than EFs applied in nonnumerical, domain-general contexts. Also, how distinct EF domains-that is, working memory, inhibitory control, and cognitive flexibility-and contents-that is, numerical versus nonnumerical-moderate the association between magnitude processing and mathematics achievement has not been fully understood. To address these issues, we investigated how magnitude processing, EFs applied to nonnumerical and numerical task stimuli, and their interactions were associated with mathematics achievement. Three hundred fifty-nine Brazilian third- to fifth-grade (8-10 years old) students completed measures of working memory, inhibitory control, and cognitive flexibility with numerical and nonnumerical task versions, nonsymbolic and symbolic magnitude comparison, and mathematics achievement. A series of regression models indicated that nonsymbolic and symbolic magnitude processing are consistently associated with mathematics achievement, even when controlling for working memory, inhibitory control, and cognitive flexibility measured with both numerical and nonnumerical contents. All EF measures were associated with mathematics achievement. However, cognitive flexibility measured with numerical content showed the strongest association. Results support the hypothesis that magnitude processing and EFs are uniquely associated with mathematics achievement. Furthermore, EFs measured with nonnumerical and numerical contents related differently to mathematics achievement, even when controlling for symbolic and nonsymbolic magnitude processing, suggesting they encompass somewhat distinct cognitive processes. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

The first steps in developing a number sense screening test for young primary school children

Number sense refers to a set of numerical processing skills that develop before entering primary school and evolve with age and experience. Research has shown the importance of these skills for mathematical achievement. Therefore, early identification of students who have difficulty in numerical processing is the key to early intervention to reduce these deficits. This study’s purpose was to design a group-administered pencil-and-paper instrument measuring numerical magnitude estimation and numerical magnitude comparison that can be used in the first three grades of primary school as a quick screening tool for number sense deficits. Three quick and easy-to-use tasks measuring non-symbolic and symbolic number sense (the number line estimation task, the area comparison task, the number comparison task) were developed and administered to a group of 316 students in the first three grades of Slovenian primary schools. The results show that these tests provide a good basis for further development of a screening test.

Deep neural network-assisted fast and precise simulations of electrolyte flows in redox flow batteries

Flow fields are a key component in redox flow batteries, which is to distribute electrolytes onto electrodes at the maximum uniformity with the minimum pump work. Achieving this design goal requires accurate simulations of electrolyte flows and identification of the dead zones where the flows become weak or stagnant. However, conventional case-by-case numerical simulation requires significant computational resources. In this work, we use deep learning to predict the electrolyte flow in flow batteries with a neural network knows as U-Net. The U-Net is well trained by learning the mapping between the input (flow field geometry) and output (velocity magnitude distribution). Results show that the pixel-wise comparison of the velocity magnitudes between the U-Net-predicted results and finite element simulated results exhibits an average Euclidean distance of 442.6 and an average R2 of 0.979, indicating that the electrolyte distribution can be accurately simulated based on the geometric characteristics of flow fields. In addition, dead zones are precisely identified by labeling the regions with low velocity magnitudes. Modifying the channel depth in these regions substantially enhances the under-rib convection, thereby improving the system efficiency by 5.5 % at 200 mA cm−2. Furthermore, compared to the numerical simulation, the U-Net-assisted prediction significantly reduces the computational time by 99.9 %. It is anticipated that the U-Net-assisted simulation provides an accurate and efficient tool for obtaining the velocity distribution of flow fields that can assist the flow field design especially in large quantities and large scale.

Fireballs-Like Explosive Peroxides Produced by the Brown-rot Fungus

Abstract: Fireballs are unusual and rare phenomena usually associated with thunderstorms, although sometimes they have been observed during earthquakes, volcano eruptions or in fair weather. There are still questions about their origination, features and interaction with the environment. In this work, a new model is shown to explain the formation of fireballs in fair weather from poplar cotton and peroxides produced by brown-rot fungi. Light emission is produced via thermal decomposition of 1,2- dioxetane phenylcoumarane or 1,2-dioxetane monolignol, from lignin inside the poplar fibers. The energy released during the explosive decaying of fireballs was calculated as being about 3 kilojoules for each gram. This value is the same order of magnitude as the estimated for the explosive fireballs decaying.

Deficits in or Preservation of Basic Number Processing in Parkinson's Disease? A Registered Report.

Neurodegenerative diseases such as Parkinson's disease (PD) have a huge impact on patients, caregivers, and the health care system. Until now, diagnosis of mild cognitive impairments in PD has been established based on domain-general functions such as executive functions, attention, or working memory. However, specific numerical deficits observed in clinical practice have not yet been systematically investigated. PD-immanent deterioration of domain-general functions and domain-specific numerical areas suggests mechanisms of both primary and secondary dyscalculia. The current study systematically investigated basic number processing performance in PD patients for the first time, targeting domain-specific cognitive representations of numerosity and the influence of domain-general factors. The overall sample consisted of patients with a diagnosis of PD, according to consensus guidelines, and healthy controls. PD patients were stratified into patients with normal cognition (PD-NC) or mild cognitive impairment (level I-PD-MCI based on cognitive screening). Basic number processing was assessed using transcoding, number line estimation, and (non-) symbolic number magnitude comparison tasks. Discriminant analysis was employed to assess whether basic number processing tasks can differentiate between a healthy control group and both PD groups. All participants were subjected to a comprehensive numerical and a neuropsychological test battery, as well as sociodemographic and clinical measures. Results indicate a profile of preserved (verbal representation) and impaired (magnitude representation, place × value activation) function in PD-MCI, hinting at basal ganglia dysfunction affecting numerical cognition in PD. Numerical deficits could not be explained by domain-general cognitive impairments, so that future research needs to incorporate domain-specific tasks of sufficient difficulty.

Photometry and kinematics of dwarf galaxies from the Apertif HI survey

Understanding the dwarf galaxy population in low density environments (in the field) is crucial for testing the current Lambda Cold Dark Matter cosmological model. The increase in diversity toward low-mass galaxies is seen as an increase in the scatter of scaling relations, such as the stellar mass--size and the baryonic Tully-Fisher relation (BTFR), and is also demonstrated by recent in-depth studies of an extreme sub-class of dwarf galaxies with low surface brightnesses but large physical sizes called ultra-diffuse galaxies (UDGs). We aim to select dwarf galaxies independent of their stellar content and to make a detailed study of their gas and stellar properties. We selected galaxies from the APERture Tile In Focus (Apertif) survey and applied a constraint on their $i$-band absolute magnitude in order to exclude high-mass systems. The sample consists of 24 galaxies, 22 of which are resolved in by at least three beams, and they span mass ranges of 8.6 $ lesssim 9.7 and a stellar mass range of 8.0 $ lesssim 9.7 (with only three galaxies having log ( msun)&gt;9). We determined the geometrical parameters of the and stellar disks, built kinematic models from the data using and extracted surface brightness profiles in the g-, r- and i- bands from the Pan-STARRS 1 photometric survey. We used these measurements to place our galaxies on the stellar mass--size relation and the BTFR, and we compared them with other samples from the literature. We find that at a fixed stellar mass, our dwarfs have larger optical effective radii than isolated optically selected dwarfs from the literature, and we found misalignments between the optical and morphologies for some of our sample. For most of our galaxies, we used the morphology to determine their kinematics, and we stress that deep optical observations are needed to trace the underlying stellar disks. Standard dwarfs in our sample follow the same BTFR of high-mass galaxies, whereas UDGs are slightly offset toward lower rotational velocities, in qualitative agreement with results from previous studies. Finally, our sample features a fraction (25&lt;!PCT!&gt;) of dwarf galaxies in pairs that is significantly larger with respect to previous estimates based on optical spectroscopic data.

Regional Stiffness and Hardening Indices: New Indicators Derived from Multidimensional Dynamic CTA for Aneurysm Risk Assessment.

Two indices, indicating the regional average stiffness and the pace of strain hardening respectively, are derived from the nonlinear stress-strain behavior obtained from biomechanical analysis of aneurysm. A comprehensive method based on electrocardiographic-gated multidimensional dynamic computed tomography angiography (MD CTA) is developed for extracting these mechanical characteristics in vivo. The proposed indices are evaluated by 26 cases including 9 healthy, one aortosclerosis, and 16 abdominal aortic aneurysm cases. The difference of SSI and dSSI value between aneurysmal and healthy groups is up to orders in magnitude. Significant correlation of these indices with the clinical indicator of aneurysm diameter is found. Logistic models based on these indices are capable to sharply discriminate the healthy and the aneurysmal arteries with AUC>0.98. This work introduces new tools and new indices for aortic mechanical assessment which may shed light on understanding the mechanical condition, pathological state and eventually benefit clinical decision-making.

Rare Earth Elements in Fe oxyhydroxides from biofilms containing iron-oxidizing bacteria

Fe oxyhydroxides extracted from modern-day biofilms with iron-oxidizing bacteria Arthrobacter spp., Gallionella spp и Leptothrix ochracea in the north-west of the East European platform display the enhanced content of rare earth elements – up to 1100 ppm. REE concentration in bacterial oxyhydroxides increase by one order in magnitude during 1 year suggesting the high sorption capacity of newly formed Fe mineral phases. La/YbN, Ce and Y anomalies in bacterial oxyhydroxides are consistent with geochemistry of the surface water facies where bacterial communities live. Isotopic composition of Nd in studied bacterial oxyhydroxides is controlled by the lithology of the Q-R underlying sediment and ambient water. 143Nd/144Nd values in Fe minerals of bacterial origin vary from 0.511570 to 0.512220 (eNd(0) from –21.8 to –9.2), the high proportion of radiogenic Nd is typical for the samples located on platform cover with Palaeozoic carbonate sediment.