Internal Patterning Research Articles

Fabrication of Cu-Infiltrated Journal Bearing by Binder Jetting Additive Manufacturing

In this study, considering the economic feasibility of products that can be produced through the binder jetting additive manufacturing process, 316L stainless steel, a widely used material with a wide particle size ranging from 15 to 106 μm, was used. The lubrication effect was increased by internal patterning through design for additive manufacturing, and journal bearing parts with excellent load resistance and wear resistance were implemented by using wear-resistant Cu as an infiltration material. In addition, to investigate the amount of Cu infiltrated as a function of porosity, the parts were pre-sintered from 1423 K to 1573 K, and the best performance was obtained when Cu was infiltrated after pre-sintering at 1473 K. As a result of rig testing of Cu-infiltrated journal bearings, mechanical properties were obtained that were more than 50% improved compared to those of mass products.

Mechanics and Morphology of Proliferating Cell Collectives with Self-Inhibiting Growth.

We study the dynamics of proliferating cell collectives whose microscopic constituents' growth is inhibited by macroscopic growth-induced stress. Discrete particle simulations of a growing collective show the emergence of concentric-ring patterns in cell size whose spatiotemporal structure is closely tied to the individual cell's stress response. Motivated by these observations, we derive a multiscale continuum theory whose parameters map directly to the discrete model. Analytical solutions of this theory show the concentric patterns arise from anisotropically accumulated resistance to growth over many cell cycles. This Letter shows how purely mechanical processes can affect the internal patterning and morphology of cell collectives, and provides a concise theoretical framework for connecting the micro- to macroscopic dynamics of proliferating matter.

Differences between ultrastructure and protein composition in straight hair fibres

Mammalian hairs are internally patterned from both a morphological and proteomic perspective to exhibit specific functional traits, including curvature, which is important for coat structure affecting thermo-insulation. Most functional traits in mammalian coats are complex emergent phenomena associated with single-fibre properties that are themselves multi-variate and poorly understood. Here we compare hair curvature, ultrastructure, microstructure, protein composition and felting (a functional attribute) between fibres from natural straight-wool mutants of domestic sheep (felting lustre-mutant sheep), their wild-type relatives and also with a straight-haired semi-lustrous breed, English Leicester. Proteomic and structural results confirmed that the straight lustre mutant fibres had a normal cuticle and the same cortical protein and ultrastructural building blocks as wild-type fibres, but differed from equivalent fibres from wild-type relatives and English Leicester in layout and relative proportions. While curved wild-type fibres had bilaterally arranged orthocortex and paracortex, and English Leicester fibres had a scatter of paracortex on a background of orthocortex, lustre mutant fibres typically had a complete or partial ring of orthocortex surrounding a paracortex core, and sometimes a central orthocortex (similar to straight human and goat hairs). Lustre mutant fibres also had a reduced abundance of some high glycine-tyrosine proteins, normally associated with the orthocortex, with a possible relationship between the protein expression of the KAP8 and KAP16 protein families and fibre felting properties. We conclude that through control of the internal fibre patterning, multiple-solutions to hair curvature are possible, and variation may affect mechanical phenotype differently. Felting lustre mutant sheep will be a useful tool for discriminating cause and effect from non-causative correlation in mammalian fibre development.

C4 photosynthesis and transition of Kranz anatomy in cotyledons and leaves of Tetraena simplex.

Tetraena simplex is an independently evolved C4 species in the Zygophylloideae (Zygophyllaceae) and a characteristic forb of saline flats in hot and sandy desert habitats. During early ontogeny, the species had a morphological shift from planar cotyledons (dorsiventral symmetry) to terete, succulent leaves (radial symmetry). We tested whether this shift had a corresponding change in internal Kranz anatomy and tissue patterning. For a comprehensive characterization of C4 photosynthesis across early ontogeny in T. simplex, structural and ultrastructural anatomical properties and localization patterns, activities, and immunoblotting of key C4 photosynthetic enzymes were compared in mesophyll and bundle sheath tissues in cotyledons and leaves. Cotyledons and leaves possessed different types of Kranz anatomy (atriplicoid type and a "Tetraena" variant of the kochioid type, respectively), reflecting the change in leaf morphology. In bundle sheath cells, key differences in ultrastructural features included increased organelle numbers and chloroplast thylakoid stacking. C4 enzymes had strict tissue-specific localization patterns within bundle sheath and mesophyll cells in both cotyledons and leaves. The decarboxylase NAD-ME maintained the highest activity, increasing from cotyledons to leaves. This classified T. simplex as fully C4 across ontogeny and a strictly NAD-ME biochemical subtype. Tetraena simplex cotyledons and leaves showed differences in Kranz type, with associated progression in ultrastructural features, and differing activities/expression levels of C4 enzymes. Furthermore, leaves characterized a new "Tetraena" variation of the kochioid Kranz anatomy.

The gendering power of genres: How female Scandinavian crime fiction writers experience professional authorship

This article introduces the notion of genre as an analytical category for the study of gender inequality in creative work. Research on gender and creative labour typically identifies external, systemic and structural causes for gender inequality in media industries. In contrast, I argue that genres, by virtue of their internal, structural and discursive patterning, play a constitutive role in regulating media producers’ gendered professional identities, shaping their struggle for recognition and structuring their economic sustainability. Rather than being merely outcomes of production processes, genres shape gender inequality: They possess gendering power that influences how media producers work, think and feel. Gendering and gendered genre norms that privilege ‘masculine’ over ‘female’ values are so hard-wired in occupational practice and professional codes of conduct that the genre itself becomes a control and boundary ascription mechanism that implicitly governs, sustains and reproduces gendered identity formation, career aspirations and biographical standing. Drawing on in-depth interviews with female producers of Scandinavian crime fiction, globally branded as Nordic Noir, I examine how female writers in Denmark have coped with and experienced the gendering effect of the genre in which they work and to which they are financially beholden. I also tease out the ways in which crime fiction, a masculine genre, causes anxiety of authorship and affects female producers’ identity and boundary work. This focus on the gendering power of genres may potentially help us understand the gender disparities in media industries – disparities that endure despite efforts at policing fair access and equal opportunity.

Combined Pharmacological and Genetic Manipulations Unlock Unprecedented Temporal Elasticity and Reveal Phase-Specific Modulation of the Molecular Circadian Clock of the Mouse Suprachiasmatic Nucleus.

The suprachiasmatic nucleus (SCN) is the master circadian oscillator encoding time-of-day information. SCN timekeeping is sustained by a cell-autonomous transcriptional-translational feedback loop, whereby expression of the Period and Cryptochrome genes is negatively regulated by their protein products. This loop in turn drives circadian oscillations in gene expression that direct SCN electrical activity and thence behavior. The robustness of SCN timekeeping is further enhanced by interneuronal, circuit-level coupling. The aim of this study was to combine pharmacological and genetic manipulations to push the SCN clockwork toward its limits and, by doing so, probe cell-autonomous and emergent, circuit-level properties. Circadian oscillation of mouse SCN organotypic slice cultures was monitored as PER2::LUC bioluminescence. SCN of three genetic backgrounds-wild-type, short-period CK1ε(Tau/Tau) mutant, and long-period Fbxl3(Afh/Afh) mutant-all responded reversibly to pharmacological manipulation with period-altering compounds: picrotoxin, PF-670462 (4-[1-Cyclohexyl-4-(4-fluorophenyl)-1H-imidazol-5-yl]-2-pyrimidinamine dihydrochloride), and KNK437 (N-Formyl-3,4-methylenedioxy-benzylidine-gamma-butyrolactam). This revealed a remarkably wide operating range of sustained periods extending across 25 h, from ≤17 h to >42 h. Moreover, this range was maintained at network and single-cell levels. Development of a new technique for formal analysis of circadian waveform, first derivative analysis (FDA), revealed internal phase patterning to the circadian oscillation at these extreme periods and differential phase sensitivity of the SCN to genetic and pharmacological manipulations. For example, FDA of the CK1ε(Tau/Tau) mutant SCN treated with the CK1ε-specific inhibitor PF-4800567 (3-[(3-Chlorophenoxy)methyl]-1-(tetrahydro-2H-pyran-4-yl)-1H-pyrazolo[3,4-d]pyrimidin-4-amine hydrochloride) revealed that period acceleration in the mutant is due to inappropriately phased activity of the CK1ε isoform. In conclusion, extreme period manipulation reveals unprecedented elasticity and temporal structure of the SCN circadian oscillation. The master circadian clock of the suprachiasmatic nucleus (SCN) encodes time-of-day information that allows mammals to predict and thereby adapt to daily environmental cycles. Using combined genetic and pharmacological interventions, we assessed the temporal elasticity of the SCN network. Despite having evolved to generate a 24 h circadian period, we show that the molecular clock is surprisingly elastic, able to reversibly sustain coherent periods between ≤17 and >42 h at the levels of individual cells and the overall circuit. Using quantitative techniques to analyze these extreme periodicities, we reveal that the oscillator progresses as a sequence of distinct stages. These findings reveal new properties of how the SCN functions as a network and should inform biological and mathematical analyses of circadian timekeeping.

A Parametric Study on the Influence of Internal Speckle Patterning for Digital Volume Correlation in X-Ray Tomography Applications

Use of the Digital Volume Correlation (DVC) technique has grown steadily in the mechanics community as a way of quantifying internal mechanical response of complex microstructures under loading. The DVC technique has been combined with internal imaging methodologies such as X-ray microcomputed tomography (X-ray microCT), confocal microscopy, and photoelasticity enabling many full field studies of bone, foam, rock, polymers, and metals. Despite all these efforts, many DVC limitations remain unknown such as those of “optimal” subset size, step size, and the quality of an internal speckle pattern. Here we investigate in detail the effects of internal speckle patterning on DVC. To help determine the optimum setup for DVC, we develop internal speckle patterns using markers ranging from 5 to 50 μm particles and study these over different resolution length scales. A correlation of pattern size and quality was determined using baseline (i.e., no deformation) and rigid body motion experiments, resulting in a recommended pattern quality parameter. We then performed a uniaxial compression experiment using the optimal pattern determined from the parametric study where we compare accuracy using DVC calculated strains and displacements with theoretical values. An in situ uniaxial compression test demonstrated DVC capabilities resulting in a 2 % error in strain computations.

Evidence of signaling benefits to contrasting internal color boundaries in warning coloration

It has been suggested that the common existence of regular patterning in aposematic prey animals makes them “stand out” from the background, improving detection and recognition. Another suggestion is that internal patterns could have a similar positive effect on predator aversion learning as prey-to-background contrast. We used wild caught blue tits (Cyanistes caeruleus) and artificial prey signals to investigate if internal color boundaries, pattern regularity and pattern symmetry affect learning. Birds in different treatments were trained, on a complex background, to discriminate between artificial prey with different nonrewarding color stimuli with a black pattern and rewarding stimuli without a black pattern, followed by a generalization test. This study provides evidence of learning benefits to internally contrasting patterns as the striped prey stimuli were learned faster than the unstriped. Also, we found no beneficial effects of pattern regularity and symmetry. The birds generalized more between prey with different black patterns than to the profitable prey, suggesting that color is of foremost importance. The generalization test also showed a greater avoidance of striped than that of unstriped prey, suggesting some attention on patterns. Thus, internal patterning may affect signal salience and in some circumstances benefit prey due to both a faster avoidance learning and generalization behavior.

Analysis of the laser patterning inside light guide panel

The objective of this research is to evaluate the feasibility of the internal patterning in the light guide panel (LGP) by applying laser engraving. LGP fabricated by the internal patterning is proposed as it offers better efficiency than is provided by bottom surface patterning. The patterns fabricated by laser engraving system could improve efficiency by approximately 40%, requiring less energy consumption in average brightness and uniformity than required by bottom surface patterned devices. Internal scatters were fabricated by Q-switched 2nd harmonic Nd:YAG laser engraving system. The performance of the fabricated LGPs was measured and its results analyzed. Modification of the shape of the LGP patterns from the simple geometry has been investigated to control the uniformity. The proposed internal scatter embedded LGP with laser engraving could provide an alternative method to conventional bottom surface scatters type with optimized patterns and geometry.

Intrasite Spatial Structure in the European Upper Paleolithic: Evidence and Patterning from the SW of France

Over the past 20 years a number of Western European Upper Paleolithic sites have been examined for internal spatial patterning by using a variety of quantitative techniques. The most commonly applied technique has been K -means clustering in one form or another. Because this technique has been applied consistently to a relatively large number of sites from a wide variety of temporal phases in the European Upper Paleolithic, it is useful to search for common patterns and consistencies in the organization of space during this time period. These analyses suggest that Upper Paleolithic sites commonly exhibit three basic modes of internal organization. Hearth focused sites are often large, complex sites with many features and distinctive global and local artifact patterning. Areal focused sites are often scatters of artifacts, and/or occur with severe natural constraints. Structure focused sites frequently show no clear indications of hearths, and are free of 'natural' constraints. They are frequently highly patterned around what may best be called "architectural structures", however.

The effect of configural orientation on perceived trajectory in apparent motion.

In three experiments, we investigated apparent motion trajectories for stimuli flashed in different locations and at different orientations. It was found that, when stimuli were presented at different orientations, apparent motion trajectories were curved, although these paths were actually circular for only a restricted range of parameters. Curved apparent motion paths were induced by orientation changes in two stimuli that differed in how their orientation was specified. One was a rectangle (orientation-specific contour); the other was a circle (orientation-specific internal patterning). The following variables influenced the extent of apparent curvature seen: (1) the amount of orientation change presented, (2) the orientation of the stimulus symmetry, (3) the salience of configural orientation, and (4) the gender of the observer.

The schizophrenic and the paranoid process.

Data are presented in support of an understanding of schizophrenic and paranoid processes as operating relatively independently in the formation and deformation of human personality. The schizophrenic process derives from a genetically determined diathesis in combination with a range of factors involving environmental stress. The effects of the schizophrenic process in the organization and integration of internal structure and the differentiation of psychic functions are found at multiple levels, including negative consequences for the integration between cognitive and affective capacities, between conceptual and perceptual functions, and in the integration and stabilization of psychic structures. The schizophrenic process is envisioned as having disorganizing and disruptive effects on different levels of psychic organization, including the levels of the organization of cognitive processes, the formation and integration of representational systems (both self and object, and the structural integration of the self-system. In contrast, the paranoid process is thought to operate in the shaping and internal patterning of the personality organization, particularly by way of crucial forms of internalization. The interaction of introjection and projection shapes the individual's self-organization and contributes to the quality of interaction with significant objects. The impact of the paranoid process in both its positive function of contributing to the building up and integration of a meaningful and constructive sense of self and capacity for psychological functioning, as well as its deviant forms of expression in the development of paranoid pathology, is discussed. Although the schizophrenic and paranoid processes operate relatively independently, their interaction and intermingling contributes to the spectrum of forms of psychopathology that characterize the schizophrenic spectrum.

Linguistic and Social Interaction in Two Communities1

S OCIOLINGUISTICS has been described as the study of verbal behavior in terms of the social characteristics of speakers, their cultural background, and the ecological properties of the environment in which they interact (Hymes 1962; Ervin-Tripp 1964). In this paper we will explore some of the formal aspects of this relationship. We will examine the language usage of specific groups and attempt to relate it to linguistically distinct dialects and styles on the one hand and variables employed in the study of social interaction on the other. The raw material for our study is the distribution of linguistic forms in everyday speech. As is usual in descriptive analysis, these forms are first described in terms of their own internal patterning at the various strata (phonemic, morphemic, etc.) of linguistic structure (Lamb 1964; Gleason 1964). Ultimately, however, the results of this analysis will have to be related to social categories. This condition imposes some important restrictions on the way in which data are gathered. Since social interaction always takes place within particular groups, linguistic source data will have to be made commensurable with such groups. We therefore choose as our universe of analysis a speech community: any human aggregate characterized by regular and frequent interaction over a significant span of time and set off from other such aggregates by differences in the frequency of interaction. Within this socially defined universe forms are selected for study primarily in terms of who uses them and when, regardless of purely grammatical similarities and differences. If two grammatically distinct alternatives are employed within the same population, both will have to be included. On the other hand, in those cases where socially significant differences in behavior are signaled by grammatically minor lexical or phonemic correlates, the latter cannot be omitted from consideration.