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Direct ink writing (DIW) technology supersedes traditional mold‐based forming methods, significantly enhancing the fabrication of personalized and customized products with complex structures. This technology particularly excels in achieving precise control over the porosity of porous constructs. This study employs inorganic Al2O3 as raw material, sodium hexametaphosphate as dispersing agent, and inorganic SiO2 micropowder as binding medium to fabricate lattice porous structures. One challenge encountered is the viscoelastic behavior of the extruded filament. When spanning the unsupported segments of the lower layer, the upper extruded filaments are susceptible to deflection or collapse, adversely affecting the porosity and dimensional fidelity of the final specimens. Experimental results revealed that a larger span and smaller modulus will cause the extruded filament to be more prone to deformation at the midpoint. The introduction of 2 wt% polyethylene glycol as a plasticizer mitigates this issue, ensuring nondeflection of the extruded filaments at a span of 6 mm. The deflection model for the extruded filament about span and modulus identifies the minimum modulus necessary to prevent or minimize deflection under given spans, which closely approximates our experimental findings, offering a valuable framework for guiding the production of high‐precision, porosity‐controlled porous structures. [ABSTRACT FROM AUTHOR]

Sulfur‐polyacrylonitrile (SPAN) is a sulfur‐based active material for next‐generation lithium‐sulfur battery cathodes. Due to the covalent bonding between sulfur chains and the polymeric backbone, the shuttle effect degrading classical sulfur‐based cathodes can be suppressed while also achieving a high active material content in the cathode. In this paper, we investigate the processability of an industrially scalable SPAN active material with 38 wt.‐% of sulfur in a water‐based and scalable process route. The potential of the SPAN material for industrial adoption and the impact of the process route on the cell performance are discussed. We show that when processed correctly, the SPAN material delivers exceptional cycling stability and good C‐rate performance with ether‐based electrolytes. However, the performance of the SPAN cathode is influenced by the mixing characteristic. Using higher mixing intensities during the slurry preparation leads to deterioration of the electrochemical performance. This can be attributed to a decreasing carbon black percolation with increasing tip speed in combination with the kinetic limitation of sulfur cathodes during Li2S2 and Li2S oxidation. [ABSTRACT FROM AUTHOR]

Architecture is a complex web of semiotics – signs, signals and signifiers. The creation of these codes, and their dynamic manipulation and interaction over time, is the lifeblood of experimental architecture practice SPAN's Doghouse project. Co‐founder Sandra Manninger explains how the project's articulation, robotic inhabitants and fluctuating symbolic meanings and languages create a complex multi‐readable architectural structure and text. [ABSTRACT FROM AUTHOR]

Matias del Campo interviews Alexandra Carlson who had a key role in founding the pioneering Architecture and Artificial Intelligence Laboratory (AR2IL) at the University of Michigan's Robotics Department and Taubman College of Architecture and Urban Planning. The synthesis of the architectural and dataset sharing adds another dimension to design possibilities. [ABSTRACT FROM AUTHOR]

Co‐founders and principals of architecture firm SPAN and architectural academics based at the University of Michigan, Matias del Campo and Sandra Manninger describe how they became aware of AI technology, setting out some key collaborations, familiarising us with the concept of 'defamiliarisation' and introducing us to some of SPAN's explorations in AI and architecture. [ABSTRACT FROM AUTHOR]

The article presents the discussion on computer-science papers emerging in proving valuable, interesting and informative for potential applications of AI in architecture. Topics include inquiry into the problem of designing architecture showing creativity, intuition, and sensibility; and opening up the possibility of style transfer such as transferring the stripes of a zebra onto a horse or reading an image through a neural network .

Potassium‐ion batteries (PIBs) are regarded as promising candidates in next‐generation energy storage technology; however, the electrode materials in PIBs are usually restricted by the shortcomings of large volume expansion and poor cycling stability stemming from a high resistance towards diffusion and insertion of large‐sized K ions. In this study, BiSbSx nanocrystals are rationally integrated with sulfurized polyacrylonitrile (SPAN) fibres through electrospinning technology with an annealing process. Such a unique structure, in which BiSbSx nanocrystals are embedded inside the SPAN fibre, affords multiple binding sites and a short diffusion length for K+ to realize fast kinetics. In addition, the molecular structure of SPAN features robust chemical interactions for stationary diffluent discharge products. Thus, the electrode demonstrates a superior potassium storage performance with an excellent reversible capacity of 790 mAh g−1 (at 0.1 A g−1 after 50 cycles) and 472 mAh g−1 (at 1 A g−1 after 2000 cycles). It's one of the best performances for metal dichalcogenides anodes for PIBs to date. The unusual performance of the BiSbSx@SPAN composite is attributed to the synergistic effects of the judicious nanostructure engineering of BiSbSx nanocrystals as well as the chemical interaction and confinement of SPAN fibers. [ABSTRACT FROM AUTHOR]

This study tested whether adults with autism spectrum disorder (ASD) show the same pattern of difficulties and absence of age‐related differences in short‐term memory (STM) as those that have been reported in episodic long‐term memory (LTM). Fifty‐three adults with ASD (age range: 25–65 years) were compared to 52 age‐, biological sex‐, and intelligence‐matched typically developing (TD; age range: 21–67 years) adults on three STM span tasks, which tested STM performance for letters (Verbal), grid locations (Visuospatial), or letters in grid locations (Multimodal). A subsample of 34 TD and 33 ASD participants ranging in age from 25 to 64 years completed a fourth Multimodal Integration task. We also administered the Color Trails Test as a measure of executive function. ASD participants' accuracy was lower than that of the TD participants on the three span tasks (Cohen's d: 0.26–0.50). The Integration task difference was marginally significant (p =.07) but had a moderate effect size (Cohen's d = 0.50). Regression analyses confirmed reduced STM performance only for older TD participants. Analyses also indicated that executive processes played a greater role in the ASD group's performance. The demonstration of similar difficulties and age‐related patterning of STM in ASD to those documented for LTM and the greater recruitment of executive processes by older ASD participants on the Integration task suggest a compensatory role of frontal processes both as a means of achieving undiminished task performance and as a possible protection against older age cognitive decline in ASD. Longitudinal research is needed to confirm this. Autism Res 2020, 13: 1970‐1984. © 2020 The Authors. Autism Research published by International Society for Autism Research and Wiley Periodicals LLC. Lay Summary: Little is known about short‐term memory (STM) in younger and older adults with autism spectrum disorder (ASD). This study tested different kinds of STM and showed that ASD adults remembered shorter sequences of letters, crosses, or letters in grid cells less well than matched participants with typical development. However, older ASD individuals performed similarly to younger ASD individuals, nor showing the reduction in performance usually seen with older age. The data suggest that ASD individuals use different underlying mechanisms when performing the tasks and that this might help protect their memory as they grow older. [ABSTRACT FROM AUTHOR]

Post‐lithium‐ion battery technology is considered a key element of future energy storage and management. Apart from high gravimetric and volumetric energy densities, economic, ecologic and safety issues become increasingly important. In that regards, both the anode and cathode materials must be easily available, recyclable, non‐toxic and safe, which renders magnesium‐sulfur (Mg−S) batteries a promising choice. Herein, we present Mg−S cells based on a sulfurated poly(acrylonitrile) composite cathode (SPAN), together with a halogen‐free electrolyte containing both Mg[BH4]2 and Li[BH4] in diglyme and a high‐specific surface area magnesium anode based on Rieke magnesium powder. These cells deliver discharge capacities of 1400 and 800 mAh/gsulfur with >99 % Coulombic efficiency at 0.1 C and 0.5 C, respectively, and are stable over at least 300 cycles. Energy densities are 470 and 400 Wh/kgsulfur at 0.1 C and 0.5 C, respectively. Rate tests carried out between 0.1 C and 2 C demonstrate good rate capability of the cells. Detailed mechanistic studies based on X‐ray photoelectron spectroscopy and electric impedance spectroscopy are presented. [ABSTRACT FROM AUTHOR]

Summary: Privacy in Vehicular Ad Hoc Networks (VANET) is fundamental because the user's safety may be threatened by the identity and the real‐time spatiotemporal data exchanged on the network. This issue is commonly addressed by the use of certified temporal pseudonyms and their updating strategies to ensure the user's unlinkability and anonymity. IEEE 1609.2 Standard specified the process of certifying pseudonym along with certificates structure. However, the communication procedure between the certifying authority and the requesting vehicle was not defined. In this paper, a new privacy‐preserving solution for pseudonym on‐road on‐demand refilling is proposed where the vehicle anonymously authenticates itself to the regional authority subsidiary of the central trusted authority to request a new pseudonyms pool. The authentication method has two phases, the first one uses anonymous tickets, and the second one is a challenge‐based authentication. The anonymous tickets are certificates that do not include the identity of the user. Instead, it contains a reference number and the certifying authority signature. The challenge authentication is identity‐less to preserve the privacy, yet it is used to prevent the misuse of tickets and the impersonation of its owner. Our proposed scheme is analyzed by the use of Burrows, Abadi and Needham (BAN) logic to demonstrate its correctness. It is also specified and checked by using the Security Protocol ANimator (SPAN) and the Automated Validation of Internet Security Protocols and Applications (AVISPA) tools. The logical demonstration proved that this privacy‐preserving authentication is assured. The SPAN and AVISPA tools illustrated that it is resilient to security attacks. [ABSTRACT FROM AUTHOR]

Purpose: To comprehensively evaluate both the acceleration and image-quality impacts of axial compression and its degree of modeling in fully 3D PET image reconstruction. Method: Despite being used since the very dawn of 3D PET reconstruction, there are still no extensive studies on the impact of axial compression and its degree of modeling during reconstruction on the end-point reconstructed image quality. In this work, an evaluation of the impact of axial compression on the image quality is performed by extensively simulating data with span values from 1 to 121. In addition, two methods for modeling the axial compression in the reconstruction were evaluated. The first method models the axial compression in the system matrix, while the second method uses an unmatched projector/backprojector, where the axial compression is modeled only in the forward projector. The different system matrices were analyzed by computing their singular values and the point response functions for small subregions of the FOV. The two methods were evaluated with simulated and real data for the Biograph mMR scanner. Results: For the simulated data, the axial compression with span values lower than 7 did not show a decrease in the contrast of the reconstructed images. For span 11, the standard sinogram size of the mMR scanner, losses of contrast in the range of 5–10 percentage points were observed when measured for a hot lesion. For higher span values, the spatial resolution was degraded considerably. However, impressively, for all span values of 21 and lower, modeling the axial compression in the system matrix compensated for the spatial resolution degradation and obtained similar contrast values as the span 1 reconstructions. Such approaches have the same processing times as span 1 reconstructions, but they permit significant reduction in storage requirements for the fully 3D sinograms. For higher span values, the system has a large condition number and it is therefore difficult to recover accurately the higher frequencies. Modeling the axial compression also achieved a lower coefficient of variation but with an increase of intervoxel correlations. The unmatched projector/backprojector achieved similar contrast values to the matched version at considerably lower reconstruction times, but at the cost of noisier images. For a line source scan, the reconstructions with modeling of the axial compression achieved similar resolution to the span 1 reconstructions. Conclusions: Axial compression applied to PET sinograms was found to have a negligible impact for span values lower than 7. For span values up to 21, the spatial resolution degradation due to the axial compression can be almost completely compensated for by modeling this effect in the system matrix at the expense of considerably larger processing times and higher intervoxel correlations, while retaining the storage benefit of compressed data. For even higher span values, the resolution loss cannot be completely compensated possibly due to an effective null space in the system. The use of an unmatched projector/backprojector proved to be a practical solution to compensate for the spatial resolution degradation at a reasonable computational cost but can lead to noisier images. [ABSTRACT FROM AUTHOR]

For masonry bridges with small spans built before 1900, there are often no documents available since such bridges were often built from experience. Surveying is often restricted to the visible parts of the structure. Geometrical assistance in the form of drilling cores is only ever at points, which inevitably have to be interpolated. Large parts of these structures are in the ground (abutments, foundations) and are largely inaccessible for adequate geometrical recording. The constitutive laws for the existing masonry can only be described with reasonable effort through minimum values from regulations. The article describes a procedure with additions to the missing documents from experience to obtain statements about the load-bearing capacity based on approximate models, which permit categorisation into decisive bridge classes based on the regulations for the structural analysis of existing road bridges and also enable usable results for the comparison between the result of categorisation and special load cases for heavy transport. [ABSTRACT FROM AUTHOR]

Delayed adjustment tasks have recently been developed to examine working memory ( WM) precision, that is, the resolution with which items maintained in memory are recalled. However, despite their emerging use in experimental studies of healthy people, evaluation of patient populations is sparse. We first investigated the validity of adjustment tasks, comparing precision with classical span measures of memory across the lifespan in 114 people. Second, we asked whether precision measures can potentially provide a more sensitive measure of WM than traditional span measures. Specifically, we tested this hypothesis examining WM in a group with early, untreated Parkinson's disease ( PD) and its modulation by subsequent treatment on dopaminergic medication. Span measures correlated with precision across the lifespan: in children, young, and elderly participants. However, they failed to detect changes in WM in PD patients, either pre- or post-treatment initiation. By contrast, recall precision was sensitive enough to pick up such changes. PD patients pre-medication were significantly impaired compared to controls, but improved significantly after 3 months of being established on dopaminergic medication. These findings suggest that precision methods might provide a sensitive means to investigate WM and its modulation by interventions in clinical populations. [ABSTRACT FROM AUTHOR]

ABSTRACT Background To determine liver span sonographically in a randomly selected population sample and identify factors that affect liver size. Methods A total of 1,789 subjects (963 females, 826 males; mean age 41.8 ± 12.8 years) underwent sonographic examination of the liver in the midclavicular line to determine liver span. Subjects underwent physical examination and blood tests and completed a standardized interview questionnaire. Results The average liver span in the midclavicular line for the overall collective was 15.0 ± 1.5 cm; the average for females was 14.9 ± 1.6 cm and 15.1 ± 1.5 cm for males. Liver span exceeded 16 cm in 24.3% of subjects. Results of the multivariate analysis showed that, of the factors potentially influencing liver span, gender, age, body mass index, body height, fatty liver ( p < 0.0001), waist-to-hip ratio ( p = 0.015), and metabolic syndrome ( p = 0.032) are significant. By contrast, diabetes mellitus, alcohol consumption, tobacco consumption, physical activity, and laboratory findings showed no influence. Conclusions Sonographic measurement of liver span in the midclavicular line is a simple method for routine clinical use. Gender, age, body mass index, waist-to-hip ratio, body height, hepatic steatosis, and metabolic syndrome are factors associated with liver span. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 42:399-404, 2014 [ABSTRACT FROM AUTHOR]

Eine wirtschaftliche Standardanwendung von Walzprofilen sind Kranbahnträger für Laufkrane. In der bisherigen Bemessungspraxis wurden und werden überwiegend HE-Profile in der Stahlgüte S235 eingesetzt, welche eine zweckmäßige Lösung für Kranbahnträger kurzer bis mittlerer Spannweiten bei kleinen bis mittleren Radlasten darstellen. Sowohl für größere Spannweiten als auch für größere Radlasten und die Kombination aus beiden kommen HE-Profile an ihre Grenzen. Im folgenden Beitrag wird der Einsatz von HD- und HL-Walzprofilen aus S355 für Kranbahnträger untersucht und die Vorteile dieser weniger bekannten Profilreihen dargestellt. On the economic design of optimized rolled section runway beams for top mounted overhead cranes. Crane runway beams are an economic standard application of hot rolled sections. In today's design practice HE sections in grade S235 are commonly used, which represents a suitable solution for crane runway beams of short to intermediate spans and small to medium wheel loads. For bigger spans as well as for higher wheel loads and the combination of both HE sections arrive to their limits. In the following article the application of HD and HL rolled-sections in grade S355 for crane runway beams are examined and the advantages of this less known section ranges are presented. Marc May Matthias Ruppert Christoph Seeßelberg [ABSTRACT FROM AUTHOR]

Einfeldrahmen in Stahlbauweise finden weite Verbreitung beim Bau von Industrie- und Lagerhallen mit moderater Spannweite. Mit Ausnahme des Dreigelenkrahmens sind die Schnittgrößen in Haupttragrichtung statisch unbestimmt und hängen somit von den Steifigkeiten der Bauteile ab. Bei der Bemessung von Stützen- und Riegelprofilen tritt dieser nichtlineare Effekt in Erscheinung und koppelt sich zudem an die Anordnung von Vouten im Eckbereich des Rahmens. Die Optimierung der Bauteile mit Hilfe einer Evolutionsstrategie offenbart, dass es aus praktischer Sicht einen Spielraum gibt, welcher favorisierte Lösungen mit adäquatem Konstruktionsgewicht enthält. Die Varianten in diesem Spielraum unterscheiden sich durch die Ausprägung der Voute, wobei sich statische und geometrische Randbedingungen bemerkbar machen. Eine Studie bespricht den Einfluss des Rahmenabstands, der Dachneigung und der gelenkigen bzw. eingespannten Lagerung der Stützen auf die optimale Wahl der Vouten. Optimization of haunched steel hall frames. Single-span frame structures are widespread to build storage and industrial buildings of moderate span width. Except three-hinged frames the stress resultants in the principal load direction are statically indeterminate and thus, depend onto the stiffness of all structural members of the frame. For the dimensioning of profiles this nonlinear effect appears and couples furthermore to the design of haunches in the corners of the frame. Using an evolution algorithm to optimize the components of the structure reveals some room to find favor solutions with adequate design weight from a practical point of view. Variants differ in forming the haunches within this scope and boundary conditions become noticeable. Studies discuss the influence of frame spacing, roof slope as well as support conditions onto the optimal design auf haunches. [ABSTRACT FROM AUTHOR]

Dividing auditory sequence into groups, or imposing rhythmic, tonal, or spatial structure during presentation, improves recall performance. Several competing computational models have been proposed to account for these effects, but little is known about the neural correlates of grouping and hence the representations that encode grouped sequences. The present study used functional magnetic resonance imaging (fMRI) to compare the auditory encoding of grouped and ungrouped lists of sub-span (six letters) and supra-span (nine letters) length in an immediate serial recall (ISR) task. Analysis of activation revealed an extensive premotor and prefrontal network, which was significantly less active when short-term memory (STM) span was exceeded during encoding. Only primary auditory cortex showed an increase in activation when memory span was exceeded. Comparison of activation for grouped and ungrouped lists showed that during the subspan phase bilateral planum temporale showed less activation for grouped stimuli, while during the supra-span phase supramarginal and inferior parietal areas were more active for grouped lists. The magnitude of both temporal and parietal activations predicted enhanced recall of grouped lists. Thus neural signatures of grouping seem to reflect more structured processing in parietal areas instead of reliance on perceptual-auditory processing in temporal regions. Hum Brain Mapp, 2011. © 2011 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Over the years, there has been a steady stream of publications on the influence that minor components and additives have on the physical properties of fat continuous systems. These have been reviewed here. Both indigenous and added components are taken into account. The various materials have been discussed, ranging from partial glycerides and phospholipids to esterified sugars and polyols. Within the publications in this area, the (sub-)micron effects that these minor components have on nucleation, crystal growth, morphology, heat capacity and polymorphic stability have been described and discussed and, sometimes, explained. Similarly, the effects on a macroscopic level, such as visual aspects, melting profiles, post-hardening and rheology have been the subject of research. Although limited compositional information, especially of additives, hinders appropriate discussions of the relevant mechanisms, some generic guidelines as to what type and strength of effect can be expected have been derived. As a general rule, a more significant influence is observed when the acyl group of the minor component (where present) is similar to those present in the fat itself. Additives may have different effects depending on the fat they are added to, their concentration and the temperature, especially with increasing undercooling (which typically reduces the effect of additives). [ABSTRACT FROM AUTHOR]

Background It is recognized that individuals with Down's syndrome have a specific deficit in verbal short-term memory. On the other hand, non-verbal short-term memory seems to be preserved or even be a strong point for these persons. Nevertheless, the extent and specificity of the deficit must be determined. To do so, we carried out a research programme that allowed us to simultaneously assess various short-term memory systems in a developmental perspective, and to compare our participants' performance to that obtained by typically developing individuals of the same mental age. Method Three span tasks are used (auditory word span/visual patterns test/Corsi blocks task) with 54 children and teenagers with Down's syndrome and 54 typically developing children as control group. Participants were matched according to their cognitive level. Results For the auditory word span task, participants with Down's syndrome obtained performances significantly lower than those of the typically developing participants. On the other hand, compared with typically developing children, children and teenagers with Down's syndrome have a spatio-sequential span significantly higher for the lowest developmental ages. No significant differences were found for visual span. Conclusions Individuals with Down's syndrome exhibited a distinctive pattern of memory performance, in addition to their developmental specificities. [ABSTRACT FROM AUTHOR]

The article discusses on the debate on computational design thinking, citing on the techniques, technologies and tools. It cites on the alternative frame for realism such as carved patterns, translucent columns and ultra-black asteroids. The article also discusses the characteristics of contemporary architectural production which evoke mood, atmospheric conditions and phenomenological traits of the sensual.

The leading figures of Modernism instilled a fear of ornament as something unclean and even criminal. Guest-Editor Matias del Campo calls for us to leave behind this phobia and engage anew with ornament for the purposes of generating mood and atmosphere. Here he describes two recent projects by SPAN, the Vienna-based architectural practice he cofounded with Sandra Manninger, which explore alternatives to the usual aesthetic canons by addressing classic architectural problems in bold new ways. [ABSTRACT FROM AUTHOR]

Is the term 'ornament' set to become redundant in architecture? With the sinuous lines produced by CNC milling machines giving way to the ever more weirdly figural products of algorithmically controlled 3D printing, decoration is increasingly an integral part of form, rather than supplementary to it. Mario Carpo - Reyner Banham Professor of Architectural Theory and History at the Bartlett School of Architecture, University College London - investigates this voxellisation, and how it drives architecture beyond human comprehension. [ABSTRACT FROM AUTHOR]