Specific Orientation Research Articles

Loss of fluorine during crosslinking by the biarylitide P450Blt proceeds due to restricted peptide orientation.

The biarylitide crosslinking enzyme P450Blt can perform crosslinking between m-F-Tyr-3 and His-5 residues within peptide substrates with concomitant and specific loss of fluorine. Our investigations suggest that a small intrinsic preference for coupling ipso to fluorine is magnified by the binding of the peptide in a specific orientation that enforces the loss of fluorine during peptide crosslinking, likely via a two-step reaction mechanism involving the non-enzyme catalysed reductive elimination of fluoride.

Mechanical guidance to self-organization and pattern formation of stem cells.

The self-organization of stem cells (SCs) constitutes the fundamental basis of the development of biological organs and structures. SC-driven patterns are essential for tissue engineering, yet unguided SCs tend to form chaotic patterns, impeding progress in biomedical engineering. Here, we show that simple geometric constraints can be used as an effective mechanical modulation approach that promotes the development of controlled self-organization and pattern formation of SCs. Using the applied SC guidance with geometric constraints, we experimentally uncover a remarkable deviation in cell aggregate orientation from a random direction to a specific orientation. Subsequently, we propose a dynamic mechanical framework, including cells, the extracellular matrix (ECM), and the culture environment, to characterize the specific orientation deflection of guided cell aggregates relative to initial geometric constraints, which agrees well with experimental observation. Based on this framework, we further devise various theoretical strategies to realize complex biological patterns, such as radial and concentric structures. Our study highlights the key role of mechanical factors and geometric constraints in governing SCs' self-organization. These findings yield critical insights into the regulation of SC-driven pattern formation and hold great promise for advancements in tissue engineering and bioactive material design for regenerative application.

Modulation of Aβ 16-22 aggregation by glucose.

The self-assembly of amyloid-beta (Aβ) peptides into fibrillar structures in the brain is a signature of Alzheimer's disease. Recent studies have reported correlations between Alzheimer's disease and type-2 diabetes. Structurally, hyperglycemia induces covalent protein crosslinkings by advanced glycation end products (AGE), which can affect the stability of Aβ oligomers. In this work, we leverage physics-based coarse-grained molecular simulations to probe alternate thermodynamic pathways that affect peptide aggregation propensities at varying concentrations of glucose molecules. Similar to previous experimental reports, our simulations show a glucose concentration-dependent increase in Aβ aggregation rates, without changes in the overall secondary structure content. We discovered that glucose molecules prefer partitioning onto the aggregate-water interface at a specific orientation, resulting in a loss of molecular rotational entropy. This effectively hastens the aggregation rates, as peptide self-assembly can reduce the available surface area for peptide-glucose interactions. This work introduces a new thermodynamic-driven pathway, beyond chemical cross-linking, that can modulate Aβ aggregation.

Inherent and induced defects in mixed-phase CuO nanoparticles

Copper (Cupric) oxide is a readily synthesized, non-toxic metal oxide with a wide range of uses, including the treatment of water, the manufacture of electronic devices, solar cells, cathodes for lithium-ion primary batteries, gas sensors, electrochromic devices, supercapacitors, and field effect transistors. The effects of Zn doping in CuO in three different concentrations (weights %) were investigated. The band gap and carrier concentration were altered due to the formation of defect energy states, lattice stresses, and the formation of ZnO, and Cu2O in addition to CuO. Temperature increases from room temperature resulted in the production of metal oxides with preferred crystal growth in specific orientations. An increase in temperature, from 300 °C to 500 °C, generated residual strain release and atomic diffusions, resulting in grain growth and a reduction in the band gap. The changes in UV and PL spectra predicted the growth kinetics involved

Optimal Protocol for Contrast-enhanced Free-running 5D Whole-heart Coronary MR Angiography at 3T.

Free-running 5D whole-heart coronary MR angiography (MRA) is gaining in popularity because it reduces scanning complexity by removing the need for specific slice orientations, respiratory gating, or cardiac triggering. At 3T, a gradient echo (GRE) sequence is preferred in combination with contrast injection. However, neither the injection scheme of the gadolinium (Gd) contrast medium, the choice of the RF excitation angle, nor the dedicated image reconstruction parameters have been established for 3T GRE free-running 5D whole-heart coronary MRA. In this study, a Gd injection scheme, RF excitation angles of lipid-insensitive binominal off-resonance RF excitation (LIBRE) pulse for valid fat suppression and continuous data acquisition, and compressed-sensing reconstruction regularization parameters were optimized for contrast-enhanced free-running 5D whole-heart coronary MRA using a GRE sequence at 3T. Using this optimized protocol, contrast-enhanced free-running 5D whole-heart coronary MRA using a GRE sequence is feasible with good image quality at 3T.

Quorum sensing inhibiting dihydropyrrol-2-ones embedded polymer/graphene oxide nanocomposite waterborne antimicrobial coatings.

With increasing antibiotic resistance and hospital acquired microbial infections, there has been a growing interest to explore alternate antimicrobial approaches. This is particularly challenging when aiming to protect surfaces over a large area to avoid contact mediated infection transmission. Quorum sensing (QS) inhibition has emerged as an alternate antimicrobial approach overcoming evolutionary stress driven resistance observed in antibiotic treatment. However, specific surface orientation requirements and limited work on delivery of small molecule QS inhibiting compounds have limited their widespread applicability certainly when it comes to coating large surfaces. Here, we report antimicrobial nanocomposite coatings overcoming the dependence on molecular orientation of QS inhibiting dihydropyrrol-2-ones (DHP) analogues and release small molecule analogues. In a systematic study, we developed poly(styrene-stat-n-butyl acrylate)/graphene oxide (GO)/DHP analogue nanocomposite antimicrobial coatings that can be easily applied to surfaces of any length scale and studied their efficacy against Staphylococcus aureus. The polymer nanocomposite was designed to undergo coating formation at ambient temperature. The antimicrobial coatings exhibited DHP dose dependent antimicrobial response both in the supernatant growth media with a ∼7-log10 reduction in cell growth and virtually a complete inhibition in cell adhesion on the surface in the best coating compared to controls. When compared, DHP-Br coatings outperformed other DHP analogues (-F and -Ph) both in limiting the cell growth in the media and cellular adhesion on the coating surface. This is the first example of nanocomposite coatings comprising QS inhibiting compounds, and their exceptional performance is expected to pave the way for further research in the field.

Wavelet Based Inpainting Detection

With the advancement in image editing tools, manipulating digital images has become alarmingly easy. Inpainting, which is used to remove objects or fill in parts of an image, serves as a powerful tool for both image restoration and forgery. This paper introduces a novel approach for detecting image inpainting forgeries by combining DT-CWT with Hierarchical Feature segmentation and with noise inconsistency analysis. The DT-CWT offers several advantages for this task, including inherent shift-invariance, which makes it robust to minor manipulations during the inpainting process, and directional selectivity, which helps capture subtle artifacts introduced by inpainting in specific frequency bands and orientations. By first applying colour image segmentation and then analysing for each segment, noise inconsistency obtained via DT-CW we can identify patterns indicative of inpainting forgeries. The proposed method is evaluated on a benchmark dataset created for this purpose and is compared with existing forgery detection techniques. Our approach demonstrates superior results compared with SOTA in detecting inpainted images. The proposed methodology source code is uploaded here: https://github.com/jmaba/Wavelet-based-inpainting-detection

STRATEGIES FOR LEARNING PRONUNCIATION ONLINE: SERBIAN EFL LEARNERS’ PERSPECTIVE

Digital tools and online teaching platforms offer vast opportunities for language learning, yet, even though many indeed focus on pronunciation practice only, there seems to be a noticeable lack of research supporting their effectiveness. The current paper investigates Serbian EFL learners' views on the possible strategies employed for successful online pronunciation practice. A total of 105 tertiary-level English-major students at the Faculty of Philology and Arts, University of Kragujevac, Serbia, participated in the pre-designed survey concerning online learning strategies with a particular focus on pronunciation practice. The primary instrument was a questionnaire consisting of three parts: part one concerned with the demographic information on the sample, part two containing statements related to offline pronunciation learning strategies and part three focusing on online pronunciation learning strategies. Based on the results, dominant strategies for pronunciation practice in face-to-face classrooms are directed toward improving individual sounds and intonation. Thus, both segmental and suprasegmental features are incorporated in the students’ pronunciation instruction. When it comes to the pronunciation learning strategies online, students seem to prefer cognitive and metacognitive strategies, while social strategies seem to lack popularity among Serbian EFL students. In general, a relatively even distribution of responses was noted for both ends of the scale for the majority of proposed strategies which is explained by the specific professional orientation of the respondents. The findings underscore important pedagogical implications not only for learning English online, but for the improvement of pronunciation practice in the Serbian EFL context in general.

Computational approaches to enhance charge transfer and stability in TPBi-(PEA)2PbI4 perovskite interfaces through molecular orientation optimization.

The optimization of material interfaces is crucial for the performance and longevity of optoelectronic devices. This study focuses on 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi), a key component in perovskite devices known for its efficient charge transfer capabilities. We investigate the TPBi-(PEA)2PbI4 heterostructure interfaces to enhance device durability by optimizing interfacial properties. Our findings reveal that those specific TPBi orientations - at 15 and 30 degrees - ensure strong electronic coupling between TPBi and (PEA)2PbI4, which improves stability at these interfaces. Furthermore, orientations at 15 and 60 degrees markedly enhance charge transfer kinetics, indicating reduced recombination rates and potentially increased efficiency in optoelectronic devices. These results not only underscore the importance of molecular orientation in perovskite devices but also open new avenues for developing more stable and efficient hybrid materials in optoelectronic applications.

Influence of Chinese cultural values on consumer decision-making: A PRISMA-based systematic review

Employing the preferred reporting items for systematic reviews and meta-analyses (PRISMA) methodology, this study provides an incisive exploration into the nexus between traditional Chinese cultural values and their impact on consumer decision-making processes. The central objective was to ascertain the degree to which these ingrained cultural values shape purchasing behaviors. Our systematic review discerns a pronounced effect of these cultural tenets on consumer choices within the Chinese market. It reveals that the purchasing decisions of Chinese consumers are inextricably linked to specific cultural value orientations. For enterprises seeking to penetrate or thrive in this market, a nuanced comprehension of these cultural dimensions is imperative for crafting successful marketing strategies and customer engagement approaches. The findings of this research are instrumental in offering crucial insights for aligning business strategies with the unique preferences and behavioral patterns of Chinese consumers.

Stereohaptic Vibration: Out-of-Body Localization of Virtual Vibration Source Through Multiple Vibrotactile Stimuli on the Forearms.

This paper proposes a novel concept of "stereohaptic vibration," which employs distributed vibration to localize vibration sources outside the body. Inspired by amplitude panning, a stereophonic sound display technique, we developed a method to localize a virtual vibration source (VVS) by polarizing the perceived intensity of multiple vibration stimuli to a specific orientation. Considering the perceptual characteristics of high-frequency vibration, the perceived intensity of the VVS was allocated to multiple vibrators according to the distance and direction of the target. The velocity discrimination performance was confirmed by utilizing four stimuli around the arm and one vibration stimulus to the palm to localize the movement of a VVS throughout the arm. Discrimination experiments of the trajectory of outgoing objects with a single arm and dual arms revealed that our approach could localize in three dimensions, even outside the body. The proposed technology for localizing external virtual vibration sources is expected to enhance the virtual reality experience.

JWST Imaging of Edge-on Protoplanetary Disks. II. Appearance of Edge-on Disks with a Tilted Inner Region: Case Study of IRAS04302+2247

We present James Webb Space Telescope imaging from 2 to 21 μm of the edge-on protoplanetary disk around the embedded young star IRAS04302+2247. The structure of the source shows two reflection nebulae separated by a dark lane. The source extent is dominated by the extended filamentary envelope at ∼4.4 μm and shorter wavelengths, transitioning at 7.7 μm and longer wavelengths to more compact lobes of scattered light from the disk itself. The dark lane thickness does not vary significantly with wavelength, which we interpret as an indication for intermediate-sized (∼10 μm) grains in the upper layers of the disk. Intriguingly, we find that the brightest nebula of IRAS40302 switches side between 12.8 and 21 μm. We explore the effect of a tilted inner region on the general appearance of edge-on disks. We find that radiative transfer models of a disk including a tilted inner region can reproduce an inversion in the brightest nebula. In addition, for specific orientations, the model predicts strong lateral asymmetries, which can occur for more than half possible viewing azimuths. A large number of edge-on protoplanetary disks observed in scattered light show such lateral asymmetries (15/20), which suggests that a large fraction of protoplanetary disks might host a tilted inner region. Stellar spots may also induce lateral asymmetries, which are expected to vary over a significantly shorter timescale. Variability studies of edge-on disks would allow us to test the dominant scenario for the origin of these asymmetries.

Touch cannot attentionally select signals based on feature binding.

For human sensory processing, cluttered real-world environments where signals from multiple objects or events overlap are challenging. A cognitive function useful in such situations is an attentional selection of one signal from others based on the difference in bound feature. For instance, one can visually select a specific orientation if it is uniquely colored. However, here we show that unlike vision, touch is very poor at feature-based signal selection. We presented two-orthogonal line segments with different vibration textures to a fingertip. Though observers were markedly sensitive to each feature, they were generally unable to identify the orientation bound with a specific texture when the segments were presented simultaneously or in rapid alternation. A similar failure was observed for a direction judgment task. These results demonstrate a general cognitive limitation of touch, highlighting its unique bias to integrate multiple signals into a global event rather than segment them into separate events.

Nobody Moves, Anybody Gets Hurt Innovation Potential Through the Perspective of Movement Processes

Companies have to be innovative to be able to stay competitive in the market and are coming under ever greater pressure to innovate as a result of the increasingly fast-paced world - they have to keep moving. However, there is no recipe for success for the practical implementation of innovations. So far, only conceptual solutions in individual areas have been resorted to. I would like to approach the problem by describing forms of innovation as movement processes and argue that structural factors for innovation potential are mapped here. Thereby, the thesis shall be strengthened that especially free processes of creation, like chaotic movements without specific target or orientation, promote actual (disruptive) innovation in companies.

Identification of Some Gem Quality Blue to Green Li-Tourmalines

Due to their appealing colors, gem quality tourmalines, particularly the blue to green Cu- and Mn-bearing Li-tourmalines known as the Paraíba type, have been of significant interest since their discovery at the end of 1980s. At the same time, the demand of other similar colored tourmalines increased. Most Paraíba-type tourmalines belong to the elbaite species; however, liddicoatite gems can also be found. Recognizing and classifying various tourmaline species, especially these valued Paraíba-type tourmalines, are important for geologists, mineralogists, mineral collectors, and gemologists. This study explores the application of Raman spectroscopy in random crystal orientations to distinguish between the elbaite and liddicoatite tourmaline species. Raman spectra were collected from faceted blue to green Li-tourmalines alongside chemical analysis using EDXRF (Energy Dispersive X-ray Fluorescence), UV-Vis-NIR (Ultraviolet-Visible-Near InfraRed Spectroscopy), and PL (Photoluminescence spectroscopy) to provide comprehensive characterization. The results show that Raman spectroscopy, particularly in the OH stretching region, is a useful tool for differentiating elbaite from liddicoatite, and this identification remains consistent regardless of crystal orientation. The fingerprint region in the Raman spectra, on the other hand, is orientation-dependent and can only differentiate the two species when detected in specific orientations. Furthermore, Paraíba-type tourmalines can be identified by visible-near infrared (Vis-NIR) spectroscopy, although not by Raman spectroscopy.

Tool wear prediction in edge trimming of MD CFRP considering interlaminar effect

The tool flank wear progresses rapidly in edge trimming of carbon fiber reinforced polymer (CFRP) components, affecting the machined surface quality and process efficiency. This paper presents a tool wear prediction method considering the unique interlaminar effect of the multi-directional (MD) CFRP in the edge trimming process. The experimental results show that different laminar configurations of MD CFRP change the tool wear progression of unidirectional (UD) plies at specific fiber orientations. The interlaminar effects from the adjacent layers with different fiber orientations are explained by their varying supporting strengths on the target layer due to the change of bouncing back height. Therefore, the interlaminar effect from two sides of a UD ply is not a simple summation of the contributions by the individual side. The machined surface roughness of unidirectional ply varies up to 30 % due to the interlaminar effect. A long short-term memory (LSTM) - back propagation (BP) network is developed to predict tool wear length, including the effect of different interlaminar configurations. With the proposed model, the effect of the interlaminar configurations on tool wear progression in edge trimming of MD CFRP is predicted quantitatively. The prediction of the wear length progression based on the developed machine learning model is validated by the experimental results.

Insights into orientation-dependent plasticity deformation of HfNbTaTiZr refractory high entropy alloy: An atomistic investigation

HfNbTaTiZr refractory high entropy alloy has emerged as a prospective structural material suitable for high-temperature applications owing to its remarkable combination of high strength, good tensile ductility and excellent high-temperature properties. However, the insufficient understanding of the mechanical responses of this refractory high entropy alloy has hindered the improvement of performance in alloy design and potential for engineering applications. Therefore, the orientation-dependent tensile behaviors of HfNbTaTiZr refractory high entropy alloy are investigated from nanoscale using molecular dynamics simulations. The simulation results show that the mechanical responses under uniaxial tension are strongly correlated to the crystallographic orientation with respect to the loading direction, and the highest Young's modulus and yield strength are achieved along [111] direction. In addition, the deformation twinning and phase transformations are charactered. The tensile behavior oriented along [001] direction is dominated by the BCC-FCC phase transformation, while that oriented along [110] or [111] direction by the BCC-HCP phase transformation. The results reveal the critical role of tensile direction in generating specific crystalline microstructures under high-strain-rate loading conditions, which can enlighten new design strategy in engineering refractory high entropy alloys with specific orientations for extreme environments.

Microstructure evolution and lath martensite precipitation behavior of Co@GNPs/CoCrMo composites fabricated by selective laser melting

Spherical cobalt nanoparticles were reduced and deposited in situ on the graphene (GNP) surface using a novel hydrothermal method, and the prepared Co@GNPs reinforced powder were uniformly dispersed in the alloy matrix. The Co@GNPs/CoCrMo composite fabricated using selective laser melting (SLM) was densely organized with reduced hole defects, and fine equiaxed grains, elongated columnar grains, and duplex ε + γ were observed in the composite organization. Meanwhile, a high density of dislocations and nanoscale stacked layer dislocations were observed at the equiaxed grain boundaries. Further, the GNPs acted as heterogeneous nucleation sites, which promoted the transformation of the γ-Co (FCC) austenite phase to the ε-Co (HCP) martensite phase by means of slip. A unique characteristic structure of nanoscale parallel-arranged lath martensite is formed on the surface of GNPs. Therefore, a co-lattice structure between ε-co and γ-co shows the specific orientation relationship between the crystallographic plane (1 1 1)γ-co//(0 0 0 2)ε-co and the crystallographic zone axis [1 1 0]γ-co//[1 1 2‾ 0]ε-co.

‘Something serious’: biopedagogies of young people, sex and drugs in Australian drug education

ABSTRACT Despite being ostensibly focussed on alcohol and other drugs, drug education often directly addresses sex – a focus subject to scant analysis. This article examines how the relationship between young people, sex and alcohol and other drugs is addressed in a dataset of 23 ‘evidence-based’ drug education texts currently recommended for use in Australian secondary schools. Approaching drug education as a ‘biopedagogy’, I argue that drug education operates as a form of governance that seeks to constitute young subjects with specific orientations not only to alcohol and other drugs but sex and health more broadly. First, I argue that drug education constitutes appropriate sex as sober, planned and with a regular romantic partner. Second, I argue that in lessons about sexual violence, drug education works with an account of consent that constitutes the targets of violence as responsible for addressing it. My analysis suggests that drug education operates as a biopolitical strategy that constitutes sex in the context of alcohol and other drug consumption as not only dangerous but wrong. Overall, this approach struggles to offer understandings and skills that may contribute to ethical sexual conduct where alcohol and other drugs are involved.

Mechanism of impact toughness enhancement obtained by globularization of αGB phase for selective laser melted Ti–6Al–4V alloy

The low impact toughness of selective laser melted (SLM) Ti–6Al–4V (Ti64) is a main factor limiting its widespread application in engineering. In this work, we've greatly improved its toughness by modifying the morphology of the α phase via annealing. Specifically, the as-built sample had a toughness of 14.87J/cm2. Annealing at 800 °C for 4 h boosted the toughness to 25J/cm2. Notably, annealing at 950 °C for 4 h increased the toughness by a remarkable 90 %, reaching an impressive 36.88J/cm2, which is comparable to its wrought counterpart. Particularly, 950 °C annealing induces the globularization of αGB phase (α phase along prior β grain boundary) while maintains the lamellar morphology of the α phase within the prior β grain. This mixed structure significantly outperforms the full lamellar structure in the 800 °C annealed sample in terms of toughness. The mechanism of toughness enhancement differs from the traditional one where thick lamellar α phase improves the toughness by increasing the crack path's tortuosity. Our study indicates that more deformation twins are activated in 950°C-annealed samples in impact test, which effectively absorb additional impact energy and improve toughness. In the 800°C-annealed sample, only a limited number of grains with specific orientations can activate deformation twins. Whereas in the 950°C-annealed sample, a broader range of grain orientations demonstrated the capability to activate deformation twins. The mechanism for twin activation in the 950°C-annealed sample is proposed. It is associated with equiaxed αGB, inducing significant interface deformation accompanied by stress concentration. This ultimately leads to the formation of the deformation twins.