Shaping Technique Research Articles

Ultrathin visible-light OCT endomicroscopy for in vivo ultrahigh-resolution neuroimaging in deep brain

Deep-brain neuroimaging, a task that demands high-resolution imaging techniques for visualizing intricate brain structures, assessing deep-seated disease histopathology, and offering real-time intervention guidance, is challenged by the resolution-depth trade-off of current methods. We propose an optical coherence tomography (OCT) endomicroscopy device for high-resolution in vivo imaging of deep brain microstructures and histopathology. A unique liquid shaping technique enables the direct fabrication of a microlens on the fiber tip of the imaging probe, optimizing imaging performance parameters, such as longitudinal focal shift, focused spot size, and working distance. In addition, a broadband visible-light source enhances axial resolution and OCT imaging contrast. As a result, the first monolithic visible-light OCT (vis-OCT) endomicroscope, with a submillimeter outer diameter (∼0.4 mm), is presented, achieving an ultrahigh resolution of 1.4 μm axial × 4.5 μm transverse in air. This compact probe allows minimally invasive in vivo deep-brain imaging in mice at a depth of 7.2 mm. Key regions in the mouse deep brain, such as the isocortex, corpus callosum, and caudate putamen, were successfully identified using our vis-OCT endomicroscope. In addition, we examined the myeloarchitectures and cytoarchitectures in the isocortex. Our findings demonstrate that the vis-OCT endomicroscope offers enhanced visualization of myelinated axon fibers and nerve fiber bundles compared to its 800 nm counterpart. This vis-OCT endomicroscope, overcoming resolution and imaging depth limitations of conventional methods, offers a novel tool for minimally invasive, ultrahigh-resolution in vivo deep brain neuroimaging.

Investigating the effect of dynamic laser beam oscillations in remote fusion cutting process

The latest research on laser beam fusion cutting has revealed significant improvements in process productivity and cut quality through the use of dynamic beam shaping techniques. While many studies have investigated dynamic beam shaping for proximity cutting, the influence of laser beam oscillations on the remote fusion cutting process remains unexplored. The present work aims to study the effect of dynamic beam shaping on the remote fusion cutting process through analytical modeling, experimental investigations, and in situ high-speed monitoring. Initially, an analytical model based on thermodynamic analysis was developed to assess the influence of circular oscillations on the process zone. This model facilitates the evaluation of process performance from an energetic perspective, providing an estimate of the maximum achievable cutting speed for the remote fusion cutting process across various operating conditions. A significant increment in process productivity could be achieved through beam oscillations. Furthermore, based on theoretical findings, the effect of circular laser beam oscillations superimposed on the processing feed direction was experimentally investigated using a 1 mm thick AISI304 stainless steel material. A 6 kW fiber laser was utilized, alongside a high-speed camera-based system for in situ process monitoring. The experimental results demonstrate a significant increase in the process productivity under dynamic beam shaping conditions, consistent with theoretical findings. Specifically, the maximum achievable cutting speed could be increased from 0.13 to 0.20 m/s. Furthermore, the cut quality of produced samples was evaluated in terms of kerf morphology and profile.

Coherent high-power terahertz vortex generation with tunable orbital angular momentum based on transverse phase mask shaping

Abstract Terahertz (THz) radiation has become a significant tool in cutting-edge research due to its superior properties. THz vortices with tunable orbital angular momentum are particularly attractive to the scientific community due to their well-defined discrete azimuthal phase around the propagation axis. However, the generation of high-power THz radiation with orbital angular momentum remains a challenge for most existing technologies. In this paper, a new method for generating coherent high-power THz vortices with tunable orbital angular momentum and frequency is proposed by combining frequency beating and transverse phase mask shaping techniques. Theoretical analyses and numerical simulations indicate that this method can generate coherent THz vortices with peak powers in the tens of megawatts and tunable topological charge numbers.

Pomegranate peel mediated silver nanoparticles: antimicrobial action against crop pathogens, antioxidant potential and cytotoxicity assay

Biologically produced silver nanoparticles are becoming a more appealing option than chemically produced antioxidants and antimicrobial agents, because they are safer, easier to manufacture and have medicinal properties at lower concentrations. In this work, we employed the aqueous pomegranate peel extract (PPE) to synthesize silver nanoparticles (PPE-AgNPs), as peel extract is a rich source of phytochemicals which functions as reducing agent for the synthesis of PPE-AgNPs. Additionally, the PPE was examined quantitatively for total phenolics and total flavonoids content. PPE-AgNPs were characterized using analytical techniques including UV–Vis spectroscopy, DLS, FTIR, XRD, HRTEM and FESEM, evaluated in vitro against the plant pathogenic microbes and also for antioxidant activities. Analytical techniques (HRTEM and FESEM) confirmed the spherical shape and XRD technique revealed the crystalline nature of synthesized PPE-AgNPs. Quantitative analysis revealed the presence of total phenolics (269.93 ± 1.01 mg GAE/g) and total flavonoids (119.70 ± 0.83 mg CE/g). Biosynthesized PPE-AgNPs exhibited significant antibacterial activity against Klebsiella aerogenes and Xanthomonas axonopodis, antifungal activity against Colletotrichum graminicola and Colletotrichum gloesporioides at 50 µg/mL concentration. The antioxidant potential of biosynthesized PPE-AgNPs was analysed via ABTS (IC50 4.25 µg/mL), DPPH (IC50 5.22 µg/mL), total antioxidant (86.68 g AAE/mL at 10 µg/mL) and FRAP (1.93 mM Fe(II)/mL at 10 µg/mL) assays. Cytotoxicity of PPE-AgNPs was valuated using MTT assay and cell viability of 83.32% was determined at 100 µg/mL concentration. These investigations suggest that synthesized PPE-AgNPs might prove useful for agricultural and medicinal purposes in the future.

Enhancing Student Attendance with Shaping Techniques: A Targeted Case Study Approach

The presence of students in school learning is part of education and learning about discipline at school. However, many students do not attend school on time so this will become a bad habit for students in the future. The aim of this research is to change the behavior of coming late to school by applying shaping techniques to students at SMK Nurul Islam Gresik. The research method used is experimental. The subjects in this research were 3 students of Nurul Islam Mayar Gresik Vocational School. The data collection method uses the Behavior Contract scale instrument, which consists of 20 statements. The analysis technique used is the independent sample T test. The results of this research show that there was a decrease in tardiness behavior in subjects before and after treatment with shaping techniques. The implication of this research is that it is hoped that it can be adopted more widely as an intervention strategy in other schools to improve student discipline and attendance.Kehadiran mahasiswa dalam pembelajaran sekolah merupakan bagian dari pendidikan dan pembelajaran mengenai Kedisiplinan di sekolah. Namun, banyak mahasiswa yang tidak memenuhi kehadiran tepat waktu di sekolah sehingga akan menjadi pembiasaan yang kurang baik untuk siswa kedepannya. Tujuan dari penelitian ini adalah untuk mengubah perilaku terlambat datang ke sekolah dengan menerapkan teknik shaping pada siswa SMK Nurul Islam Gresik. Metode penelitian yang digunakan adalah eksperimental. Subjek dalam penelitian ini adalah 3 orang siswa SMK Nurul Islam Mayar Gresik. Metode pengumpulan data menggunakan Instrumen skala Behavior Contract yang berjumlah 20 pernyataan Teknik Analisa yang digunakan yaitu Uji independent sample T Test. Hasil penelitian ini menunjukkan bahwa terjadi penurunan perilaku keterlambatan pada subjek sebelum dan sesudah dilakukan treatment dengan teknik shaping Implikasi dari penelitian ini yaitu diharapkan dapat diadopsi secara lebih luas sebagai strategi intervensi di sekolah-sekolah lain untuk meningkatkan kedisiplinan dan kehadiran siswa.

Single‐Shot Non‐Invasive Imaging Through Dynamic Scattering Media Beyond the Memory Effect via Virtual Reference‐Based Correlation Holography

AbstractNon‐invasive wide‐field imaging through dynamic random media is a sought‐after goal with important applications ranging from medical diagnosis to remote sensing. However, some existing methods, such as speckle correlation‐based techniques, are limited in field of view due to the memory effect; while some other methods, such as wavefront shaping and transmission matrix techniques, face considerable challenges when applied in dynamic scenarios because of the complexity involved in modulation and measurement. These limitations significantly impede the effectiveness and applicability of these approaches. Here, the concept of virtual reference light (VRL), which allows for the reconstruction of the original object with just a single‐shot detection of the speckle is proposed. Experimental results demonstrate that the imaging field achieves a 3.8‐fold memory effect range. In the experimental setup, the light source and detector are positioned on one side of the random medium, while the sample is placed on the opposite side, enabling non‐invasive detection. Imaging results with both static and dynamic scattering media are presented to verify the feasibility of the proposed method, offering an effective solution for real‐time target imaging and detection.

Comprehensive Analysis of Input Shaping Techniques for a Chain Suspended from an Overhead Crane

Abstract This work investigates the use of input shaping techniques for controlling oscillations in a chain suspended from an overhead crane, aiming to enhance crane operations without sacrificing speed or safety. The study focuses on two specific input shaping strategies: step-input and polynomial-input shapers. The step-input shaper applies discrete changes at determined intervals, whereas the polynomial-input shaper utilizes a continuous function to adjust the crane's input throughout its operation. Numerical simulations assess the effectiveness of these techniques in reducing oscillations across various vibration modes of the chain and examine their impact on overall system performance metrics such as maneuver time, kinetic energy, robustness, and operational smoothness. Results from comprehensive simulations indicate that both input shapers significantly eliminated residual vibrations found in time-reduced inputs. The polynomial-input shaper demonstrated enhanced performance in decreasing the residual kinetic energy, and it promoted smoother operation and better adaptability to variations in chain length.

The shaping of milk-flavored white tea: More than a change in appearance

Tea's popularity and flavor are influenced by factors like cultivation and processing methods and shaping techniques also have an impact on tea flavor. This study employed targeted metabolomics and chemometrics to investigate how shaping techniques affect the flavor of milk-flavored white tea (MFWT). The results showed that the tea cake sample with the shortest pressing time (Y90) has the highest amino acid content and milky aroma intensity. There were variations in amino acids, catechins, and soluble sugars among MFWT samples with different shaping techniques. The total contents of amino acids and catechins in tea cake sample (Y90) were significantly lower than those in the loose tea sample (SC) and bundle-like tea sample (SG), while the total sugar content was significantly higher than that in SC (P<0.05). Additionally, the content of volatiles presenting milky aroma (VIP&OAV>1) in Y90 remained lower relative to SC and SG (P<0.05), but the proportion was not different from that in SC and SG, minimally affecting the overall flavor. The short-time pressing method might be suitable for mass production of MFWT. These findings provide insights into improving the tightness of the appearance of MFWT with minimal impact on tea flavor.

A 62.5 kHz-BW 92 dB-SNDR noise-shaping SAR ADC with NS-CAL method

DAC mismatch is a significant error in NS-SAR ADCs, as it introduces essentially nonlinear behavior and limits the number of bits in the DAC array. In this paper, we propose a novel foreground digital calibration method for NS-SAR ADCs. This method, combined with noise shaping technique, improves calibration accuracy and eliminates the impact of error accumulation on high-bit weights. Thus, it increases the number of bits in the DAC array in NS-SAR ADCs, and decreases the noise floor caused by quantization error. We implemented this design using a 110-nm CMOS process. As a result, post-layout simulation shows 92 dB SNDR and 108 dB SFDR under × 16 OSR and 1.5 V supply. Compared with conventional foreground calibration method, the SNDR increases from 81 dB to 92 dB and the SFDR increases from 84 dB to 108 dB with a power consumption of 40 μW, resulting in a FoMs of 182 dB and a FoMw of 15.3 fJ/conversion-step, respectively.

Basic Setup and Coil Embolization Technique for Ruptured Cerebral Aneurysms

For treating ruptured cerebral aneurysms, it is important to understand the setup and basic technique of coil embolization. Safe and effective embolization relies on preoperative considerations that determine the treatment strategy, guide the optimization of the therapeutic environment, and help in the selection of appropriate device systems. Moreover, during aneurysmal embolization, basic techniques for microcatheter shaping and navigation, safe coil introduction, and precise use of occlusion balloons are indispensable. Microcatheter shaping should be based on three-dimensional digital subtraction angiography findings as well as the axes of the parent artery and aneurysm. The operator must understand the advantages and disadvantages of the two methods for navigating the microcatheter into the aneurysm. Furthermore, it is essential to preoperatively simulate and understand the approaches for managing aneurysmal embolization-related complications, such as intraoperative aneurysmal rupture and thromboembolism. Mastery of these steps is mandatory before undertaking embolization of ruptured cerebral aneurysms.

Impact of altering phase modulation and geometrical shape of laser beam via a phase-only spatial light modulator on laser-induced fluorescence

This study investigates the impact of modulating and shaping a laser beam via a phase-only spatial light modulator (SLM) on the intensity of the laser-induced fluorescence (LIF) signal. Different phase modulations ranging from 0 to 2π are applied to the SLM window to evaluate the effect of the modulated beam on the emitted LIF signal from extra virgin olive oil EVOO samples. The laser beam is also shaped into circular and square geometries with varying diameters to determine the optimum size for maximizing the LIF signal strength. The results reveal that the highest LIF signal intensity could be obtained after modulating the incident laser beam with phase shifts of 0 and 2π, with an improvement factor of approximately 3 for Avanti olive oil and 1.42 for Al Jouf olive oil. Furthermore, laser beam shaping into a circular aperture with a radius of 2.45 mm or a square aperture with a side length of 2.45 mm yields the highest LIF signal improvement, with enhancement factors of approximately 2.9 for Avanti olive oil and 1.42 for Al Jouf olive oil. This work demonstrates the potential of SLM-based beam shaping techniques to optimize LIF measurements by tailoring the wavefront characteristics of the excitation laser source.

A Study on the Basic Figure Skating Program for Children with Intellectual Disabilities Applying Shaping Techniques

A Study on the Basic Figure Skating Program for Children with Intellectual Disabilities Applying Shaping Techniques

Phase preservation of orbital angular momentum of light in multiple scattering environment

Recent advancements in wavefront shaping techniques have facilitated the study of complex structured light’s propagation with orbital angular momentum (OAM) within various media. The introduction of spiral phase modulation to the Laguerre–Gaussian (LG) beam during its paraxial propagation is facilitated by the negative gradient of the medium’s refractive index change over time, leading to a notable increase in the rate of phase twist, effectively observed as phase retardation of the OAM. This approach attains remarkable sensitivity to even the slightest variations in the medium’s refractive index (∼10−6). The phase memory of OAM is revealed as the ability of twisted light to preserve the initial helical phase even propagating through the turbid tissue-like multiple scattering medium. The results confirm fascinating opportunities for exploiting OAM light in biomedical applications, e.g. such as non-invasive trans-cutaneous glucose diagnosis and optical communication through biological tissues and other optically dense media.

Castillo Decorated Ceramics as Boundary Objects: A Technological Reappraisal of the North Coast Tradition from Peru During the Early Intermediate Period

ABSTRACT On Peru’s northern coast, the frequent findings of Castillo Decorated ceramics in Virú (200–600/700 BCE) and Moche (100–800 CE) archaeological contexts have led to definition of a northern coastal tradition. Presumably, these ceramics were produced by a community of potters who possessed and transmitted their own technical traditions for nearly eight centuries, independent of the elites. A recent study of Virú and Moche shaping techniques reveals that Castillo Decorated ceramics were mainly produced by hammering, a typical Virú percussion technique. However, one exception is found at the Uhle Platform at Moche, where some of these ceramics were manufactured by coiling, a Moche technique. To reconsider the North Coast tradition, in particular the spatial and chronological distribution of Castillo Decorated ceramics, I apply the boundary object concept to understand the use of two distinct and contemporary shaping techniques for production of the same vessel form.

First identification of a Neanderthal bone spear point through an interdisciplinary analysis at Abric Romaní (NE Iberian Peninsula)

Osseous industry has been observed at an increasing number of Neanderthal sites. Bone fragments were used for practical purposes, and a range of bone shaping techniques were employed. The variability of bone tools observed in different assemblages reflects considerable functional diversity. However, no bone spear points have been reported from these contexts. A comprehensive analysis of a bone spear point from the Middle Palaeolithic site of Abric Romaní (Barcelona, Spain) is presented. Through an interdisciplinary, multi-technique, and multi-scale approach combining technology, taphonomy, and functional analysis, compelling evidence for manufacture, use, and hafting was uncovered. The specimen exhibits clear signs of intentional knapping. The presence of microscopic linear impact marks, an impact fracture at the tip and potential internal stress fractures indicate its use as a spear. Furthermore, the observed wear pattern and a morphological adjustment of the trabecular tissue support the hafting hypothesis. Abric Romaní contributes to our understanding of Neanderthal hunting behaviour and the significance of composite bone tools in their technological repertoire 50,000 years ago. This discovery highlights the flexibility and adaptability of Neanderthal technology, providing evidence of bone technology that is sometimes obscured in the archaeological record and offering valuable insights into their hunting strategies during the Middle Palaeolithic.

Metalworking Influence on the Corrosion Behaviour of Sterling Silver and Silver Plated Copper

ABSTRACT Metalworking methods for silver and silver plated copper artefacts may strongly influence their corrosion behaviour. Various surfaces were generated on sterling silver coupons as well as silver plated copper coupons to simulate traditional shaping techniques and surface finishing procedures on historical silver artefacts. Coupons were either polished by hand, by a fabric disc on a polishing machine, or submitted to a hammering process in reference to the as-received state. All samples were subjected to various aging protocols, such as natural aging, a thioacetamide (TAA) gas test (NBN EN ISO 4538:1995) and a Na2S immersion test (NBN EN ISO 8891:1998). The various surface finishing procedures led to marked differences in the tarnishing behaviour which were evaluated by colorimetry, optical microscopy, and scanning electron microscopy.

A 2nd-order noise-shaping SAR-assisted pipeline ADC with order-boosted gain-error-shaping

This paper presents a 4th-order interstage gain error shaping (GES) technique in pipeline successive approximation register (SAR) analog-to-digital converters (ADCs), which can substantially suppress the in-band quantization leakage error induced by the gain error. It is realized by simply arranging a low-order cascaded-integrator feed-forward (CIFF) structure in the first stage. In addition, the comparator noise and quantization error can be shaped together with the gain error in the proposed architecture. Verified by simulation in a 28-nm CMOS process, the prototype achieves a signal-to-noise-and-distortion ratio (SNDR) of 77.8 dB over 25-MHz bandwidth (BW) with oversampling ratio (OSR) of 8. Within a gain error range of −33 % to +33 %, the SNDR of the ADC deviates less than 3 dB. Under a 1 V supply voltage, the ADC consumes 3.75 mW and exhibits a Scherier figure of merit (FoMs) of 176 dB.

‘It looks better than a bowl of mush’: Views on the use of food design strategies, including 3D food printing, to improve meals for people with dysphagia

To improve meals for people with dysphagia, we explored the views of people with dysphagia, their supporters and allied health professionals on a range of food design strategies (e.g. food shaping and food presentation techniques), including 3D food printing. From November 2021 to February 2022, an online survey of (1) adults with dysphagia (n = 30) and (2) supporters of people with dysphagia and allied health professionals (n = 22) was conducted. The survey included multiple choice, Likert scale and open-ended questions. Data was analysed descriptively. Most participants across the two groups had used at least one food design strategy for texture-modified foods and none had used 3D food printing. People with dysphagia were less likely to use food shaping techniques in preparing their texture-modified meals than other respondents. Supporters of people with dysphagia and allied health professionals were more likely than people with dysphagia to use food shaping techniques and to consider that 3D food printing could improve the visual appeal and enjoyment of texture-modified foods. A range of issues impacting the feasibility of 3D food printing were identified. The use of food design strategies for texture-modified foods may increase the food choices and mealtime enjoyment of people with dysphagia. Further research exploring how people with dysphagia and their supporters engage with 3D food printing could identify further influences on their future use of these technologies.

Enhanced genetic algorithm through scattering media by searching-strategy optimization

Feedback-based wavefront shaping techniques are efficient approaches to compensate for multiple scattering and achieve desired focuses inside or through turbid media. In this paper, we introduced the negative linear (NL) hypothesis as the criterion to optimize the feedback-based optimization approaches, such as genetic algorithm (GA). This hypothesis reveals that the key to improving the parameters to their optima lies in acquiring maximum initial convergence speed and maintaining a negative linear decline thereafter. Based on the hypothesis, an efficient genetic algorithm based on searching-strategy optimization (GA-SSO), which applies dual adaptive control of mutation and fixed linear fitness scaling selection, was proposed to accelerate the convergence speed. The simulations and experiments confirmed that NL is a basic guide to optimize the parameters to the optima of feedback-based wavefront shaping techniques.

Rotor pole and stator tooth shaping in FSPM machines for torque performance optimization

Purpose This study aims to obtain the minimum torque ripple at the maximum average torque for Flux-switching permanent magnet (FSPM) machines. Design/methodology/approach This paper is about torque performance optimization of the FSPM machines. To achieve that, finite element analysis and genetic algorithm (GA) are used. Five different designs are simulated, optimized and compared on their air gap flux density, back electromotive force, cogging torque, average torque, torque density and torque ripple. Findings After the thousands of iterations, its proved that all proposed shaping techniques have potential for reducing torque ripple and cogging torque, with slightly reduced average torque. The best design is the joint stator and rotor shaping, Design V, which results in the lowest torque ripple and cogging torque. The techniques should be applicable to FSPMs with other stator slot/rotor pole number combinations. Originality/value In this paper, rotor pole shaping by notching, chamfering and generic shaping, stator tooth shaping and joint shaping techniques are investigated for 12 s/10p FSPM machines. Rotor and stator flanks are optimized separately and jointly, by using finite element analysis and GA for optimization to achieve maximum average torque and minimum torque ripple. Five different design is implemented and compared, respectively.