Complex Geometric Patterns Research Articles

Fractal dimension and lacunarity measures of glioma subcomponents are discriminative of the grade of gliomas and IDH status.

Since the overall glioma mass and its subcomponents-enhancing region (malignant part of the tumor), non-enhancing (less aggressive tumor cells), necrotic core (dead cells), and edema (water deposition)-are complex and irregular structures, non-Euclidean geometric measures such as fractal dimension (FD or "fractality") and lacunarity are needed to quantify their structural complexity. Fractality measures the extent of structural irregularity, while lacunarity measures the spatial distribution or gaps. The complex geometric patterns of the glioma subcomponents may be closely associated with the grade and molecular landscape. Therefore, we measured FD and lacunarity in the glioma subcomponents and developed machine learning models to discriminate between tumor grades and isocitrate dehydrogenase (IDH) gene status. 3D fractal dimension (FD3D) and lacunarity (Lac3D) were measured for the enhancing, non-enhancing plus necrotic core, and edema-subcomponents using preoperative structural-MRI obtained from the The Cancer Genome Atlas (TCGA) and University of California San Francisco Preoperative Diffuse Glioma MRI (UCSF-PDGM) glioma cohorts. The FD3D and Lac3D measures of the tumor-subcomponents were then compared across glioma grades (HGGs: high-grade gliomas vs. LGGs: low-grade gliomas) and IDH status (mutant vs. wild type). Using these measures, machine learning platforms discriminative of glioma grade and IDH status were developed. Kaplan-Meier survival analysis was used to assess the prognostic significance of FD3D and Lac3D measurements. HGG exhibited significantly higher fractality and lower lacunarity in the enhancing subcomponent, along with lower fractality in the non-enhancing subcomponent compared to LGG. This suggests that a highly irregular and complex geometry in the enhancing-subcomponent is a characteristic feature of HGGs. A comparison of FD3D and Lac3D between IDH-wild type and IDH-mutant gliomas revealed that mutant gliomas had ~2.5-fold lower FD3D in the enhancing-subcomponent and higher FD3D with lower Lac3D in the non-enhancing subcomponent, indicating a less complex and smooth enhancing subcomponent, and a more continuous non-enhancing subcomponent as features of IDH-mutant gliomas. Supervised ML models using FD3D from both the enhancing and non-enhancing subcomponents together demonstrated high-sensitivity in discriminating glioma grades (~97.9%) and IDH status (~94.4%). A combined fractal estimation of the enhancing and non-enhancing subcomponents using MR images could serve as a non-invasive, precise, and quantitative measure for discriminating glioma grade and IDH status. The combination of 2-hydroxyglutarate-magnetic resonance spectroscopy (2HG-MRS) with FD3D and Lac3D quantification may be established as a robust imaging signature for glioma subtyping.

Generation of Controllable Patterned Nanofibrous Networks by Electrospinning Lithography: Simultaneous Detection and Adsorption toward Cesium Ions

Micropattern-controlled multifunctional materials have gained significant attention for various applications. In particular, a control pattern obtained by the alternation of the electric field through electrospinning can be obtained from a two-dimensional sheet to a three-dimensional microarchitecture. Herein, we present a novel direct-write patterning technique as a technical platform to precisely fabricate controlled multifunctional nanofibrous materials using a combination of electrospinning and electrospraying. A polydimethylsiloxane (PDMS)-based sacrificial mask placed on an electrospun nanofibrous network was used as the background collector, wherein the nanospheres were sequentially electrosprayed. Complex geometrical patterns such as simple figures, numbers, and letters were generated using a negatively patterned PDMS-based sacrificial mask. Using this technique, dual-functional nanofibrous composite materials comprising cellulose acetate nanofibers embedded with 0.05 M chrysoidine G and 5 wt % Prussian blue nanoparticles were successfully fabricated in different patterns and utilized for the detection and adsorption of Cs+ ions. The as-prepared composite exhibited an excellent Cs+ ion adsorption capacity with a maximum value of 54.293 mg g–1 and detected Cs+ ions up to a very low concentration of 1.0 mg L–1. Thus, electrospinning lithography is a promising and versatile technique for generating multifunctional materials that can be used in various chemical and biological applications.

Ontogeny of a tessellated surface: Carapace growth of the longhorn cowfish Lactoria cornuta

Biological armors derive their mechanical integrity in part from their geometric architectures, often involving tessellations: individual structural elements tiled together to form surface shells. The carapace of boxfish, for example, is composed of mineralized polygonal plates, called scutes, arranged in a complex geometric pattern and nearly completely encasing the body. In contrast to artificial armors, the boxfish exoskeleton grows with the fish; the relationship between the tessellation and the gross structure of the armor is therefore critical to sustained protection throughout growth. To clarify whether or how the boxfish tessellation is maintained or altered with age, we quantify architectural aspects of the tessellated carapace of the longhorn cowfish Lactoria cornuta through ontogeny (across nearly an order of magnitude in standard length) and in a high‐throughput fashion, using high‐resolution microCT data and segmentation algorithms to characterize the hundreds of scutes that cover each individual. We show that carapace growth is canalized with little variability across individuals: rather than continually adding scutes to enlarge the carapace surface, the number of scutes is surprisingly constant, with scutes increasing in volume, thickness, and especially width with age. As cowfish and their scutes grow, scutes become comparatively thinner, with the scutes at the edges (weak points in a boxy architecture) being some of the thickest and most reinforced in younger animals and thinning most slowly across ontogeny. In contrast, smaller scutes with more variable curvature were found in the limited areas of more complex topology (e.g., around fin insertions, mouth, and anus). Measurements of Gaussian and mean curvature illustrate that cowfish are essentially tessellated boxes throughout life: predominantly zero curvature surfaces comprised of mostly flat scutes, and with scutes with sharp bends used sparingly to form box edges. Since growth of a curved, tiled surface with a fixed number of tiles would require tile restructuring to accommodate the surface's changing radius of curvature, our results therefore illustrate a previously unappreciated advantage of the odd boxfish morphology: by having predominantly flat surfaces, it is the box‐like body form that in fact permits a relatively straightforward growth system of this tessellated architecture (i.e., where material is added to scute edges). Our characterization of the ontogeny and maintenance of the carapace tessellation provides insights into the potentially conflicting mechanical, geometric, and developmental constraints of this species but also perspectives into natural strategies for constructing mutable tiled architectures.

(De)Constructing the Madonna’s Cloth of Honor

Abstract The present study centers on pieced textiles included in Marian paintings of the Proto-Renaissance era rendered in Tuscany. The complex geometric patterns of these cloths mimic those found in the Islamic textiles that were then being imported into Europe, consumed by the aristocracy, and later imitated by Italian cloth makers. On a basic level, their colors and patterning reference the virtues of the Virgin, her mission to bring about the Incarnation of Christ, her selflessness, virtuous character, and majesty. They also contribute to her humanization since these are material objects that belonged in the aristocratic domestic setting and which were familiar to the patrons who paid for the works. On a deeper level, they provide complex layers of meaning, some of which derive from Moorish iconography. They reference the perfection of God’s creation and the promise of an affable afterlife. They also evoke the remote lands where the lives of the Virgin and Christ unfolded. By inserting pieced cloths into Marian iconography, artists were following a long established tradition of utilizing the piecing technique in Early Medieval sacred practice, an issue that until now has not been recognized.

Andaman–Nicobar–Sumatra Margin Revisited: Analysis of the Lithospheric Structure and Deformation Based on Gravity Modeling and Distribution of Seismicity

The Andaman–Nicobar–Sumatra subduction margin, with a well-developed Benioff zone down to ~ 200 km depth, extends over 1300 km along strike and has a lateral extent of ~ 200 km. Two-dimensional (2D) profiles based on generalized inversion of free-air gravity anomaly data across different segments of the Andaman–Nicobar sector of the margin were analyzed by reconstructing the geometry of the converging India–Eurasia lithospheric plates. Detailed 2D structures of the Ninetyeast Ridge (NER), fore-arc basin, volcanic arc, back-arc basin, spreading ridge, Sewell Rise, Mergui Ridge and Mergui Basin, and depths of Moho and the lithosphere–asthenosphere boundary were delineated. The volcanic arc is located at a distance of ~ 150–200 km from the trench and is marked by a zone of positive gravity anomaly separated from the trench by the fore-arc basin with a zone of gravity low. The topographic and gravity anomaly patterns show complex geometrical patterns over the volcanic arc due to the presence of a number of regional faults striking parallel to the trench axis developing a series of pull-apart (transtensional) basins as well as the interaction of the spreading ridges on the overriding plate. A narrow zone of negative gravity anomaly (~ − 185 to − 110 mGal) observed in the gravity model of the margin is interpreted to be associated with fore-arc shear fault above a zone of fractured oceanic crust with a thick sedimentary layer, located above a zone of sharp bending of the eastward converging Indian lithosphere in the fore-arc basin. A high concentration of seismicity and a trench-parallel band of moderate moment energy release along this fault might have been caused by concentrated deformation within the zone of flexing of the descending plate. A wide fore-arc (> 200 km) and the enhanced deformation of the subducting Indian oceanic plate in central sectors possibly resulted from increased interaction between the NER and the Andaman trench and extension in the Andaman back-arc. Appearance of a second moderate energy band and shifting of seismicity toward the trench axis following the 2004 MW 9.2 mega-event are apparently caused by the migration of the stress field from deeper to shallower part of the Indian lithosphere. A similar type of seismicity migration toward shallower part of the descending plate has been recorded along other subduction margins around the globe.

Исследование орнаментированных изделий из кости стоянки Ольская с применением трехмерного моделирования

This paper discusses the practical application of three-dimensional modelling technologies in studying bone artefacts with engraved images of the paleometal era. To achieve the study goal, we carried out a comprehensive analysis of the antler crest obtained from excavations at the Olskaya site, one of the key archaeological sites of the Tokarev culture in the Northern Priokhotye. The artefact under discussion has a complex geometric pattern, which made it possible to use it to test various tools of 3D modelling technology. As a result of our research, we reconstructed the operational sequence of the item production, which involved splitting a reindeer antler to obtain a blank, planing, double-sided cutting of teeth, surface preparation by grinding, ornamentation, and perforation. The linear ornamentation on the crest makes up a composition of horizontal motifs as stripes of small rectangles and zigzags made in double lines. 3D scanning technologies made it possible to obtain accurate data on the morphometric parameters of decorative elements, the sequence of their application and the tools used. As a result of our measurements, we found out that the metric characteristics ofwhole rectangles in the ornamented composition differ significantly. The study results showed a minimum difference in the cut lines ’depth, both in rectangles of all rows and diagonal stripes. The revealed features made it possible to assume that one master who used the same tool cut the ornament. The nature of the processing traces shows that the design of the teeth and decoration were made with different tools. The obtained data indicate the presence of specialization in the toolkit of bone carving production and a generally high level of bone processing technologies among the Tokarev culture people.

Capillary transfer of soft films

Existing transfer technologies in the construction of film-based electronics and devices are deeply established in the framework of native solid substrates. Here, we report a capillary approach that enables a fast, robust, and reliable transfer of soft films from liquid in a defect-free manner. This capillary transfer is underpinned by the transfer front of dynamic contact among receiver substrate, liquid, and film, and can be well controlled by a selectable motion direction of receiver substrates at a high speed. We demonstrate in extensive experiments, together with theoretical models and computational analysis, the robust capabilities of the capillary transfer using a versatile set of soft films with a broad material diversity of both film and liquid, surface-wetting properties, and complex geometric patterns of soft films onto various solid substrates in a deterministic manner.

Designer DNA architecture offers precise and multivalent spatial pattern-recognition for viral sensing and inhibition.

DNA, when folded into nanostructures with a specific shape, is capable of spacing and arranging binding sites into a complex geometric pattern with nanometre precision. Here we demonstrate a designer DNA nanostructure that can act as a template to display multiple binding motifs with precise spatial pattern-recognition properties, and that this approach can confer exceptional sensing and potent viral inhibitory capabilities. A star-shaped DNA architecture, carrying five molecular beacon-like motifs, was constructed to display ten dengue envelope protein domain III (ED3)-targeting aptamers into a two-dimensional pattern precisely matching the spatial arrangement of ED3 clusters on the dengue (DENV) viral surface. The resulting multivalent interactions provide high DENV-binding avidity. We show that this structure is a potent viral inhibitor and that it can act as a sensor by including a fluorescent output to report binding. Our molecular-platform design strategy could be adapted to detect and combat other disease-causing pathogens by generating the requisite ligand patterns on customized DNA nanoarchitectures.

A Bayesian approach for wavenumber identification of metamaterial beams possessing variability

Abstract Recent developments in additive manufacturing have allowed for a number of innovative designs in elastic metamaterials and phononic crystals used in several applications, including vibration attenuation. Complex geometric patterns that were otherwise very expensive or unpractical to produce are currently feasible. However, the 3D printing also introduces variability, which can greatly affect the dynamic performance of the metastructure. This work investigates the effects of manufacturing variability on the wavenumber identification of beams with evenly attached resonators, produced from Selective Laser Sintering. A combination of a correlation-based technique and a Bayes framework is proposed to identify the effective wavenumber and the most probable values of some of the design parameters. Typically of interest, for vibration attenuation using metamaterials, are the mass ratio and the resonator natural frequency. For this purpose an analytical model is derived, assuming an infinite number of resonators tuned to the same frequency. These parameters can be highly affected by the manufacturing variability because they are dependent on complex geometrical features of the metastructure. It is shown that the proposed approach can estimate the most likely values of the parameters with less than 4% difference when compared to a benchmark approach; the latter is not only more complex and time demanding, but also based on indirect measurements. Understanding the effects of this variability on the wave propagation represents an important step towards proposing robust designs with respect to the attenuation performance.

Formation of Geometric Patterns in the Architectural Decoration: An Investigation on the Ilkhanids’ Period

The Ilkhanids made considerable changes in their ancestors’ legacy after capturing Iran caused the creation of complex geometric patterns. Exhaustive research has been undertaken about the features of decoration of this era; however, the raised question is how this progress could have happened in spite of slaughtering or secluding the artists. The purpose of this study is to point out the role of the most effective factors in the formation of the decorations with complex geometric patterns during the Ilkhanids’ era. This study implements a descriptive-historical approach with reference to written library sources. The analysis of the observations shows that Iranian rulers and scholars, especially Nasir al-Din Tosi, have played a key role in this development. This includes especially Nasir al-Din Tosi who is the composer of several fields including astronomy, ethics, history, logic, jurisprudence, mathematics, medicine, poetry, and philosophy as well he translated from the Greek geometry books. His success influenced Mongols. Eventually, he was appointed in several administration positions. His position influenced the promotion and progress of the geometry and math and their application in architecture and engineering. In fact, it can be said that the interaction of architects and mathematicians, which was Tosi’s brainchild, brought about a turning point in the Ilkhanids’ art and architecture, especially geometric decorations.

Feature‐based Classification of Protein Networks using Confocal Microscopy Imaging and Machine Learning

AbstractFluorescence imaging has become a powerful tool to investigate complex subcellular structures such as cytoskeletal filaments. Advanced microscopes generate 3D imaging data at high resolution, yet tools for quantification of the complex geometrical patterns are largely missing. Here we present a computational framework to classify protein network structures. We developed a machine‐learning method that combines state‐of‐the‐art morphological quantification with protein network classification through morphologically distinct structural features enabling live imaging–based screening. We demonstrate applicability in a confocal laser scanning microscopy (CLSM) study differentiating protein networks of the FtsZ (filamentous temperature sensitive Z) family inside plant organelles (Physcomitrella patens).

GEOMETRIA ED ELASTICITÀ: FOLDING DI UN SOLIDO, DRIPPING DI UN’ASTA ELASTICA E STRUTTURE SELF-OSCILLATING

The leitmotiv of the described research activity is the situation in which an elastic solid or an elastic structure can spontaneously generate complex geometrical patterns, when subjected to extreme deformation. In this context, folding and faulting are described for a three-dimensional elastic solid with extreme anisotropy. The dripping of an elastic rod is presented (as generated by configurational forces) and finally the possibility of a self-oscillating elastic system is introduced, where an elastic structure oscillates with a given frequency when subject to a steady energy input.

Quantum transport senses community structure in networks.

Quantum time evolution exhibits rich physics, attributable to the interplay between the density and phase of a wave function. However, unlike classical heat diffusion, the wave nature of quantum mechanics has not yet been extensively explored in modern data analysis. We propose that the Laplace transform of quantum transport (QT) can be used to construct an ensemble of maps from a given complex network to a circle S^{1}, such that closely related nodes on the network are grouped into sharply concentrated clusters on S^{1}. The resulting QT clustering (QTC) algorithm is as powerful as the state-of-the-art spectral clustering in discerning complex geometric patterns and more robust when clusters show strong density variations or heterogeneity in size. The observed phenomenon of QTC can be interpreted as a collective behavior of the microscopic nodes that evolve as macroscopic cluster "orbitals" in an effective tight-binding model recapitulating the network. python source code implementing the algorithm and examples are available at https://github.com/jssong-lab/QTC.

Research on complex 3D tree modeling based on L-system

L-system as a fractal iterative system could simulate complex geometric patterns. Based on the field observation data of trees and knowledge of forestry experts, this paper extracted modeling constraint rules and obtained an L-system rules set. Using the self-developed L-system modeling software the L-system rule set was parsed to generate complex tree 3d models.The results showed that the geometrical modeling method based on l-system could be used to describe the morphological structure of complex trees and generate 3D tree models.

Echocardiographic Evaluation of Pulmonary Pressures and Right Ventricular Function after Pediatric Cardiac Surgery: A Simple Approach for the Intensivist.

Pulmonary hypertension (PH) is diagnosed using cardiac catheterization and is defined as an elevation of mean pulmonary artery pressure (PAP) greater than 25 mmHg. Although invasive hemodynamics remains the gold standard and is mandatory for disease confirmation, transthoracic echocardiography (TTE) is an extremely useful non-invasive and widely available tool that allows for screening and follow-up, in particular, in the acute setting. TTE may be a valuable alternative, allowing for direct measurement and/or indirect assessment of PAP. Because of the complex geometric shape and pattern of contraction of the right ventricle (RV), as well as the inherent complexity of cardiac repair, no single view or measurement can provide definite information on RV function and PAP and/or pulmonary vascular resistance. In addition, specific training and expertise may be necessary to obtain the views and measurements required. Some simple measurements may be of help when rapid evaluation is mandatory and potentially life saving: the assessment of tricuspid and/or pulmonary valve regurgitant jet and the use of the Bernoulli equation allow for measurement of PAP. Measurements such as the analysis of the pulmonary Doppler wave flow, the septal curvature, or the eccentricity index, assessing ventricular interdependence, are useful for indirect assessment. A four-chamber view of the RV gives information on its size, hypertrophy, function (fractional area change), and tricuspid annular plane systolic excursion as an evaluation of the longitudinal function. Based on these simple measurements, TTE can provide detection of PH, measurement or estimation of PAP, and assessment of cardiac function. TTE is also of importance in follow up of PH as well as providing an assessment of therapeutic strategies in the postoperative setting of cardiac surgery. However, PAP may be misleading as it is dependent on cardiac output and requires accurate measurements. In the presence of residual lesions, analyses of some Doppler measurements may be misleading and not reflect real PAP. Should the TTE evaluation reveal non-conclusive, invasive hemodynamics remains the gold standard.

Organization strategies in the Rey-Osterrieth Complex Figure in children with ADHD

The aim of this study was to analyze ADHD diagnosed children´s process of copy, organization strategies and recall phase of Rey-Osterrieth Complex Figure. This study corresponds to an ex post facto retrospective design with two groups, one quasi control. Seventy children between 8 and 14 years old were evaluated; 35 with ADHD and 35 without these diagnoses, paired by sex, age and instruction level. To reach the proposed objective, the process of copying, organizational strategies and memory of the Rey- Osterrieth Complex Figure were evaluated. The Rey-Osterrieth Complex Figure is a test which consists of copying phase and posterior playing back memory phase of a complex geometric pattern. Results showed a lower yield for the group with ADHD both in copy and memory process, with greater use of C and D types of copy reproduction, being the use of type D expected for younger children. These results allow further analysis of the performance of children with ADHD regarding organizational strategies providing expertise in the conceptualization, evaluation and treatment of the disorder.

Use of Ultrasound to Modified Electrodeposited Silver and Silver-Tin Microstructures and Composition without Chemical Additives

Properties of electrodeposited coatings are directly related to their morphology and structure, which are strongly influenced, among others, by the presence of organic additives and electrodeposition parameters (current density, DC vs pulsed current). An attractive possibility results in the use of ultrasound to influence the microstructure without using chemicals, or at least, by reducing their quantity. Ultrasound is expected to have several effects on deposits, by heating the liquid or by generating solution movements that cause convection flows or cavitation bubbles, accompanied by chemical effects. Many works in the literature describe the beneficial effect of ultrasound in plating, reporting finer grains, reduced porosity and increased brightness. Even the penetration of nickel in complex geometric pattern has been reported. In the present study, conventional cyanide silver as well as silver-tin electrolytes were used to examine the effect of current density and ultrasound on the composition, structure and texture of the coatings. Silver-tin alloys were used for such materials as electric contacts because of the excellence in hardness and wear resistance. The goal was to determine the effect of ultrasound (20 kHz and 575 kHz) on sample microstructure and morphology. To insulate the effect of cavitation bubbles from convection flow, all coatings had to be elaborated exactly with the same agitation in absence or presence of ultrasound, at an “equivalent flow” condition. Plotting the silver structures identified by XRD vs. current density in still conditions, two main categories appeared: one poorly structured and the other following the [110] orientation. This is confirmed by SEM and EBSD measurements. When changing from still to mechanically stirred conditions, the value of the current density threshold moves from 2.5mA/cm² to 5mA/cm². This coating microstructure modification threshold is situated at higher current density values when coatings are produced under sonication (575 kHz or 20 kHz), while agitation is kept constant. In both cases, the shift is about 15 mA/cm². It is interesting to note that silver electrodeposits elaborated under 20 kHz ultrasound conditions appear to be less oriented than those obtained under high frequency conditions, with RTChklvalues dropping from 12 to 8 for the [110] orientation. Use of ultrasound during silver coating elaboration, irrespective of hydrodynamic conditions kept otherwise constant, makes it possible to modify significantly the microstructures and morphology of deposits without relying on chemical additives. In the case of silver-tin alloy electrodeposition, it is important to note that the current density variations coupled to the use of ultrasound leads to significant variations in properties of coatings (color, crystalline composition and alloy composition). For equivalent hydrodynamic agitation, silver is predominant at low current density and tin prevails at higher ones. If low frequency ultrasound is applied, Ag3Sn replace the tin, and for high frequency ultrasound, the coating is formed by an intermetallic compound of tin and silver irrespective of the current density. Finally, in all cases, agitation is always beneficial to widen the current density range favourable for structural modifications without the risk of coating deterioration due to burning. Moreover, at the same level of agitation, use of ultrasound offers more advantages because it ensures harder and less structured deposits in increased current density ranges, and offer modifications equally important as in the case of chemical additives use. Figure 1: crystalline orientation of silver deposits at various current densities in presence of ultrasound or at an “equivalent” agitation Figure 2: composition of silver-tin alloy in presence of ultrasound or at an “equivalent” agitation Figure 1

Assessing the multiscale architecture of muscular tissue with Q-space magnetic resonance imaging: Review.

Contraction of muscular tissue requires the synchronized shortening of myofibers arrayed in complex geometrical patterns. Imaging such myofiber patterns with diffusion-weighted MRI reveals architectural ensembles that underlie force generation at the organ scale. Restricted proton diffusion is a stochastic process resulting from random translational motion that may be used to probe the directionality of myofibers in whole tissue. During diffusion-weighted MRI, magnetic field gradients are applied to determine the directional dependence of proton diffusion through the analysis of a diffusional probability distribution function (PDF). The directions of principal (maximal) diffusion within the PDF are associated with similarly aligned diffusion maxima in adjacent voxels to derive multivoxel tracts. Diffusion-weighted MRI with tractography thus constitutes a multiscale method for depicting patterns of cellular organization within biological tissues. We provide in this review, details of the method by which generalized Q-space imaging is used to interrogate multidimensional diffusion space, and thereby to infer the organization of muscular tissue. Q-space imaging derives the lowest possible angular separation of diffusion maxima by optimizing the conditions by which magnetic field gradients are applied to a given tissue. To illustrate, we present the methods and applications associated with Q-space imaging of the multiscale myoarchitecture associated with the human and rodent tongues. These representations emphasize the intricate and continuous nature of muscle fiber organization and suggest a method to depict structural "blueprints" for skeletal and cardiac muscle tissue.

Distributed temperature sensor testing in liquid sodium

Rayleigh-backscatter-based distributed fiber optic sensors were immersed in sodium to obtain high-resolution liquid-sodium temperature measurements. Distributed temperature sensors (DTSs) functioned well up to 400°C in a liquid sodium environment. The DTSs measured sodium column temperature and the temperature of a complex geometrical pattern that leveraged the flexibility of fiber optics. A single Ø 360μm OD sensor registered dozens of temperatures along a length of over one meter at 100Hz. We also demonstrated the capability to use a single DTS to simultaneously detect thermal interfaces (e.g. sodium level) and measure temperature.

Bisous model—Detecting filamentary patterns in point processes

The cosmic web is a highly complex geometrical pattern, with galaxy clusters at the intersection of filaments and filaments at the intersection of walls. Identifying and describing the filamentary network is not a trivial task due to the overwhelming complexity of the structure, its connectivity and the intrinsic hierarchical nature. To detect and quantify galactic filaments we use the Bisous model, which is a marked point process built to model multi-dimensional patterns. The Bisous filament finder works directly with the galaxy distribution data and the model intrinsically takes into account the connectivity of the filamentary network. The Bisous model generates the visit map (the probability to find a filament at a given point) together with the filament orientation field. Using these two fields, we can extract filament spines from the data. Together with this paper we publish the computer code for the Bisous model that is made available in GitHub. The Bisous filament finder has been successfully used in several cosmological applications and further development of the model will allow to detect the filamentary network also in photometric redshift surveys, using the full redshift posterior. We also want to encourage the astro-statistical community to use the model and to connect it with all other existing methods for filamentary pattern detection and characterisation.