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This article describes a bison rib bone foreshaft from the Blackwater Draw site, New Mexico. The object was recovered by James Hester in 1963, during the excavation of locality 4, and it was subsequently cataloged as a modified bone tool but not recognized as a hafting element. It is currently held in the Blackwater Draw Museum collections. This analysis provides a detailed description of the artifact's features and establishes its provenience from a Folsom context. A survey of known Paleoindigenous hafting implements and a discussion of theoretical Folsom foreshaft designs serve to reinforce the classification of the tool as a component of the Folsom weapon delivery system. The tool was likely broken during use and later recycled as a pressure flaker or as a polishing instrument. With the help of 3D imagery, a reconstructed model was printed and fitted with large and small Folsom points to test ideas borrowed from the theoretical literature on Folsom foreshaft design. [ABSTRACT FROM AUTHOR]

The article outlines key intersections between two Eastern European Jewish printing businesses during the nineteenth century. The first is the Shapira printing house, located first in Slavuta, and later in Zhytomyr. The second is the Romm printing and publishing house, Vilna, the largest Jewish printing house in Eastern Europe at the time. The first significant interaction between these two printing houses was a fierce disagreement over the printing rights of the Babylonian Talmud. However, they progressed to an economic cooperation in further printings of the Babylonian Talmud. Eventually, Romm's printing house purchased Shapira's printing house and closed it as part of preparations for the printing of another edition of the Talmud. The cultural contexts discussed in the article are part of and shed light on predominant tensions within European Jewish society at the time: the dispute between the Ḥasidim and the Mitnaggedim, and the dispute between maskilim and traditionalists. [ABSTRACT FROM AUTHOR]

Volumetric printing, an emerging additive manufacturing technique, builds objects with enhanced printing speed and surface quality by forgoing the stepwise ink-renewal step. Existing volumetric printing techniques almost exclusively rely on light energy to trigger photopolymerization in transparent inks, limiting material choices and build sizes. We report a self-enhancing sonicated ink (or sono-ink) design and corresponding focused-ultrasound writing technique for deep-penetration acoustic volumetric printing (DAVP). We used experiments and acoustic modeling to study the frequency and scanning rate-dependent acoustic printing behaviors. DAVP achieves the key features of low acoustic streaming, rapid sonothermal polymerization, and large printing depth, enabling the printing of volumetric hydrogels and nanocomposites with various shapes regardless of their optical properties. DAVP also allows printing at centimeter depths through biological tissues, paving the way toward minimally invasive medicine. [ABSTRACT FROM AUTHOR]

Christiaan Friedrich Wilhelm was one of the early bookbinders at the Cape of Good Hope. Working in the first half of the nineteenth century, he was part of the first cohort of artisan-bookbinders that followed in the wake of the arrival of the first bookbinder to arrive in the Cape in 1784. He was also part of the cohort of artisan-bookbinders that plied their trade before the dominance of large printing, bookbinding, and stationery supply firms from the middle of the nineteenth century. Christiaan Friedrich Wilhelm plied his trade against the background of significant social, political and economic trends of European imperial expansion and migration, colonisation, and human enslavement. His life at the Cape intersected with the of transition of the Cape from the rule of the Dutch East India Company and the rise of the British Empire, at a time when the Cape was still deeply embedded in an economy of slavery. Human enslavement at the Cape was to have a profound impact on his life. [ABSTRACT FROM AUTHOR]

Ceramic 3D printing is a promising technology that overcomes the limitations of traditional ceramic molding. It offers advantages such as refined models, reduced mold manufacturing costs, simplified processes, and automatic operation, which have attracted a growing number of researchers. However, current research tends to focus more on the molding process and print molding quality rather than exploring printing parameters in detail. In this study, we successfully prepared a large-size ceramic blank using screw extrusion stacking printing technology. Subsequent glazing and sintering processes were used to create complex ceramic handicrafts. Additionally, we used modeling and simulation technology to explore the fluid model printed by the printing nozzle at different flow rates. We adjusted two core parameters that affect the printing speed separately: three feed rates were set to be 0.001 m/s, 0.005 m/s, and 0.010 m/s, and three screw speeds were set to be 0.5 r/s, 1.5 r/s, and 2.5 r/s. Through a comparative analysis, we were able to simulate the printing exit speed, which ranged from 0.0751 m/s to 0.6828 m/s. It is evident that these two parameters have a significant impact on the printing exit speed. Our findings show that the extrusion velocity of clay is approximately 700 times faster than the inlet velocity at an inlet velocity of 0.001–0.010 m/s. Furthermore, the screw speed is influenced by the inlet velocity. Overall, our study sheds light on the importance of exploring printing parameters in ceramic 3D printing. By gaining a deeper understanding of the printing process, we can optimize printing parameters and further improve the quality of ceramic 3D printing. [ABSTRACT FROM AUTHOR]

DcAFF (discontinuous aligned fibre filament) is a novel material for fused filament fabrication (FFF) 3D printing made of highly aligned discontinuous fibres produced using high performance discontinuous fibre (HiPerDiF) technology. It reinforces a thermoplastic matrix to provide high mechanical performance and formability. Accurate printing of DcAFF poses a challenge, especially for complex geometries, because: (i) there is a discrepancy between the path where the filament experiences the adhering pressure from the filleted nozzle and the nozzle path; and (ii) the rasters display poor adhesion to the build platform immediately after deposition, which causes the filament to be dragged when the printing direction changes. This paper explains the implication of these phenomena on steering capabilities and examines the techniques for improving DcAFF printing accuracy. In the first approach, the machine parameters were adjusted to improve the quality of the sharp turning angle without changing the desired path, but this showed insignificant effects in terms of precision improvements. In the second approach, a printing path modification with a compensation algorithm was introduced. The nature of the inaccuracy of the printing at the turning point was studied with a first-order lag relationship. Then the equation to describe the deposition raster inaccuracy was determined. A proportional–integral (PI) controller was added to the equation to calculate the nozzle movement in order to bring the raster back to the desired path. The applied compensation path is shown to give an accuracy improvement in curvilinear printing paths. This is particularly beneficial when printing larger circular diameter curvilinear printed parts. The developed printing approach can be applied with other fibre reinforced filaments to achieve complex geometries. [ABSTRACT FROM AUTHOR]

Additive manufacturing in large‐scale construction is an ongoing research topic that shows significant potential to overcome the challenges in terms of efficient material usage and process automation in construction. A large challenge in deposition based additive manufacturing processes of concrete material is to ensure the structural stability while printing. Due to the weak material properties of the fresh concrete, it has to be ensured that during the printing process the not fully cured printed structure is able to carry its own weight. This requires process stabilization and a proper process control to prevent a collapse of the structure. Therefore, a numerical model of the printing process that takes into account the time dependent material behavior of the applied concrete as well as the printing path and the process parameters is necessary to support the process planning. Within the framework of project B04 of the collaborative research center TRR277 – Additive Manufacturing in Construction, a novel path‐based finite element simulation was developed in which the simulated geometry is constructed directly from the printing trajectory. Additionally, this approach allows the time‐dependent material properties of fresh concrete to be modeled directly and efficiently into the mesh of the printed structure. Since the computation of large scale printing processes with finite element simulations is quite expensive, there exists a need for a much faster computational model. In this contribution, the implementation of a surrogate model based on a neural network and its deployment to optimize the interlayer waiting time is presented. [ABSTRACT FROM AUTHOR]

Electrohydrodynamic (EHD) jet printing, as one of the most popular micro/nano-scale additive manufacturing methods, is still facing challenges in large-height printing and conformal printing due to poor electric field stability. The newly proposed electric field-driven (EFD) jet 3D printing has claimed better electric field stability. To reveal changing behaviour and generation mechanism of the electric field in 3D printing, an electric field model for EFD jet 3D printing was built and further validated by simulation and experiments (line width and critical voltage vs. printing height). Then, the advantage of the EFD method over EHD was confirmed by a case application of conformal printing with a height difference of larger than 9 mm and a multi-layer structure with a height of 5 mm and a line width of 20 μm. Therefore, the EFD jet 3D printing offers the possibility of achieving 3D printing in a larger height range with better electric field stability. [ABSTRACT FROM AUTHOR]

The article focuses on the Washington Talking Book & Braille Library (WTBBL) and their display of titles about love in February 2023.

In this study, the combinatorial dependence in double magnet master for energy-assisted magnetic recording was investigated by the micromagnetic framework. Four kinds of master media, which are soft single magnet (SSM), hard single magnet (HSM), soft double magnet (SDM) and hard double magnet (HDM), were compared. Comparing single magnet and double magnet master media, more adequate combination of double magnet master media was discussed. The HSM, SDM, and HDM master media can write line/space (L/S) pattern with bit length of 20 nm, while the double magnet master media can clearly print L/S patterns comparing with single magnet in case of 10 nm. For higher coercivity EAMR media, the larger printing field causes larger recording field difference by utilizing SDM master media while in case of HDM the recording field difference is almost constant even if the printing field increases. As a result, since the recording field difference of SDM becomes larger than that of HDM as the printing field strengthens, thus, SDM master media can write the servo signals onto higher coercivity EAMR media. It was concluded that it is important for the low coercivity parts of double magnet master media to have a larger saturation magnetization due to enhancement of large recording field difference. [ABSTRACT FROM AUTHOR]

In this research, the effects of fumed silica (FS) on the Ultraviolet (UV)-ink rheological behavior and processing windows were discussed. Objects using different concentrations of FS inks were printed by the modified UV-Direct ink writing (DIW) printer. The function of fumed silica in the ink-based system has been verified, and the processing scope has been expended with a suitable amount of FS combined with the UV light. The results show that the combination of a suitable amount of FS with the UV-DIW system reaches fast and accurate printing with a larger processing window compared to the non-UV system. However, an excessively high concentration of FS will increase the yield stress of the ink, which also increases the requirement of extrusion unit and the die-swelling effects. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to determine whether a clinician can assess critical print size (CPS) and/or reading fluency by listening to a visually impaired patient reading aloud across a range of print sizes on an MNREAD chart, rather than needing to plot and analyse reading speed data as a function of print size. Methods: Fifty‐six low vision participants were audio‐recorded reading an MNREAD chart under standard conditions. Two experienced raters listened to the recordings and made judgments of the CPS (logMAR), and of the level of reading fluency achieved at large print sizes on a 4‐point rating scale. Reading times were plotted as a function of print size to determine the CPS as the smallest print size that supported the participant's maximum reading speed (MRS) by inspection, and the MRS as the mean reading speed across print sizes including, and larger than, the CPS. Results: Listened CPS judgments made for each rater were slightly larger than the CPS values obtained by inspection (mean differences 0.04logMAR (p = 0.06), 0.08logMAR (p < 0.01); limits of agreement (LoA) ±0.28logMAR, ±0.39logMAR, respectively). CPS judgments were consistent both between raters (mean difference 0.04logMAR [p = 0.18]; LoA ±0.42logMAR) and between two judgments made by each rater (mean differences 0.00logMAR (p = 1.0), 0.03logMAR (p < 0.05); LoA ±0.23logMAR, ±0.17logMAR). Reading fluency could be categorised as 'functional' (MRS > 80 wpm) or 'non‐functional' (MRS < 80 wpm) with a sensitivity of 88%–90% and a specificity of 100%. Conclusions: Experienced raters listening to a patient reading an MNREAD chart can determine a clinically useful estimate of critical print size and can discriminate maximum reading speeds that are above and below that likely to provide sustained reading ability. Listening to a patient reading an MNREAD chart is an option for the low vision clinician's armoury of assessments. [ABSTRACT FROM AUTHOR]

The development of high-resolution molecular printing allows the engineering of analytical platforms enabling applications at the interface between chemistry and biology, i.e. in biosensing, electronics, single-cell biology, and point-of-care diagnostics. Their successful implementation stems from the combination of large area printing at resolutions from sub-100 nm up to macroscale, whilst controlling the composition and volume of the ink, and reconfiguring the deposition features in due course. Similar to handwriting pens, the engineering of continuous writing systems tackles the issue of the tedious ink replenishment between different printing steps. To this aim, this review article provides an unprecedented analysis of the latest continuous printing methods for bioanalytical chemistry, focusing on ink deposition systems based on specific sets of technologies that have been developed to this aim, namely nanofountain probes, microcantilever spotting, capillary-based polymer pens and continuous 3D printing. Each approach will be discussed revealing the most important applications in the fields of biosensors, lab-on-chips and diagnostics. [ABSTRACT FROM AUTHOR]

Two sandstone slabs from a new Norian tetrapod tracksite in the Löwenstein Formation of southern Germany preserve a set of tracks including both tridactyl and pentadactyl ichnites, referred to theropod dinosaur and sphenosuchian crocodylomorph trackmakers, respectively. A very large manus print hints at the presence of a hitherto unknown large quadrupedal archosaur in the Norian fauna of southern Germany. The material includes one of the oldest records of crocodylomorph tracks presently known, in agreement with the skeletal record from the same formation. [ABSTRACT FROM AUTHOR]

This article presents a wideband scalable 17.7–20.2-GHz 1024-element $K$ -band satellite communication (SATCOM) receive (Rx) phased array with reconfigurable polarization. The phased array uses silicon Rx beamformer (BF) chips and silicon low-noise amplifiers (LNAs) and is able to receive either linear, rotated linear, circular clockwise, or anticlockwise polarization. It demonstrates a measured 3.47° half-power beamwidth (HPBW), more than 25-dB cross-polar discrimination (XPD), and +8.1-dB/K gain-to-noise (G/T) per polarization, and has more than 80-dB Tx-band isolation. The phased array is able to scan to ±70° in all planes without grating lobes and $\cos ^{1-1.2}(\theta)$ scan loss. The array aperture measures 22.4 cm $\times22.4$ cm. To our knowledge, this is the largest single printed circuit board (PCB) SATCOM $K$ -band phased-array receiver to date with the highest G/T and represents the highest level of integration at millimeter waves. [ABSTRACT FROM AUTHOR]

This case study details the techniques, strategies, and workflow used by Sam Houston State University's (SHSU) Newton Gresham Library in preparing materials to submit and claim with the Texas A&M University System Joint Library Facility (JLF). The article provides an overview of JLF history and operations, and details the critical factors leading to SHSU removing large numbers of print materials from its collection. Additionally, the article discusses why SHSU elected to leverage the services offered by JLF, examines challenges encountered, and reviews techniques employed to enhance the pre-check processing required to participate in JLF's shared collection. [ABSTRACT FROM AUTHOR]

The article focuses on the Bible Society of South Africa's (BSSA) commitment to providing Bibles for everyone, highlighting the recent blessing of Gary Jordaan with a large-print Bible to accommodate his poor vision, expressing gratitude for the gift.

The utilization of components fabricated by directed energy deposition (DED) faces certain limitations that hinder its widespread application. These critical challenges primarily include significant errors in dimension accuracy caused by the unreliable build-up of flowing powder and low surface quality arising from the interlayer cumulative effect and powder adhesion. The present study aims to comprehensively investigate the impact of process parameters and deposition height on the geometrical errors observed in the thin-walled structures fabricated by DED. By establishing a rational relationship between the dimensional error and the sample height, the mechanism underlying the influence of deposition height on printing stability and sustainability is elucidated. Furthermore, an innovative building strategy incorporating a variable speed is proposed to eliminate protrusions at the end of the components. The study also examines the surface roughness of inclined thin walls, revealing a correlation between roughness and both position and angle. The presence of adhering powder on the front side of the parts and the formation of a molten oxide layer on the backside result in a diminished impact of angle on roughness. Ultimately, the findings of this study are validated through the fabrication of a thin-walled axisymmetric curved structure, providing a guide for the printing of large special-shaped parts. [ABSTRACT FROM AUTHOR]

Objective: To determine the significance of presurgical planning of three-dimensional (3D) printing for resection of a large abdominal pheochromocytoma (PCC) and paraganglioma (PGL).Patients and Methods: Thirty patients were enrolled in the present study. Groups A and B included 15 patients each. Twenty-one patients were diagnosed with a PCC and 9 had a PGL. Twenty-five patients had hypertension; the other 5 patients were shown to have PCCs/PGLs during routine physical examination. Tumors with a maximum diameter > 10 cm were defined as large tumors and included in our study. All patients underwent open surgical procedures. The surgeries in Group A were performed with 3D printing and reconstruction, while the surgeries in Group B were performed without "3D help." Online virtual and printed 3D models were available preoperatively.Results: The operative time was much shorter in Group A than Group B (152.6 ± 20.1 vs 214.9 ± 29.7 min, P < .001). Greater blood loss was recorded in Group B than Group A (459.6 ± 98.9 vs 196.7 ± 68.8 mL, P < .001). No severe complications (Clavien-Dindo Ⅲ-Ⅴ) occurred in either group. Pneumonia and lower extremity thrombosis were diagnosed in 2 Group A patients. Slow surgical wound healing and blood transfusion were recorded in 4 Group B patients.Conclusion: Preoperative stereographic 3D printing models were of great value when planning resection of a large PCC/PGL. Specifically, 3D printing models were shown to reduce the operative time and blood loss. [ABSTRACT FROM AUTHOR]

Material extrusion-based non-planar additive manufacturing (AM) using 6-axis industrial robot arms shows great promise for three-dimensional (3D) printing of non-planar parts, despite its typical use of a single large coarse nozzle and high printing time. Here, a non-planar multinozzle AM method capable of achieving high resolution large-scale 3D printing with short printing time using 6-axis robots is reported. A custom Multinozzle Toolpath Generator (MTG), based on non-planar parameterized surface projection, is used to compute the orientation of a multinozzle extrusion array along the curvature of a 3D scanned substrate. The method is demonstrated by the fast 3D printing of large periodic structures (up to an area of ∼5.2 × 104 mm2 within 20 min) consisting of interconnected epoxy composite microscaffolds on a single curvature sinusoidal surface and a double curvature surface of an actual aircraft casing, with an error of 15 μm. The method could be used for AM in various fields such as tissue engineering, microfluidic channels, and porous acoustic coatings of aircraft components. [Display omitted] • Non-planar 3D printing toolpath generation for multinozzle printhead. • Multinozzle control using 6-axis robot and collision detection with the surface. • Non-planar additive manufacturing of large-scale microscaffold networks. • Flexible 3D printing method applicable on double curvature substrates. [ABSTRACT FROM AUTHOR]

Digital concrete processes are a series of unit operations, similar to a chemical engineering process, each subject to their own rheological and other performance requirements, such as homogeneity, etc. In this article we examine the concrete extrusion 3D-printing process from this standpoint, first decomposing it into individual unit operations. We examine the role that residence time distributions play in the overall process, and then analyze how large scale printing to structural heights could be performed continuously. We then focus on the critical step of secondary (inline) mixing just before extrusion from the standpoint of mixing processes in the chemical processing industries. This unit operation is then analyzed in the context of scaleup to larger print areas and larger flowrates, finding that increase in viscosity plays a major role in power requirements and printhead mass. Further research questions are then raised based on these analyses. [ABSTRACT FROM AUTHOR]

[Display omitted] • A microfluidic synthesis process for CsPbBr 3 /Cs 4 PbBr 6 NCs was optimized. • Colloidal CsPbBr 3 /Cs 4 PbBr 6 NCs with the highest PLQY of 86.9% were obtained. • A luminescent ink was produced by the as-synthesized CsPbBr 3 /Cs 4 PbBr 6 NCs. • The ink was used to print large high-resolution patterns and fabricate mini-LED. • The narrow green emission of the mini-LED well obeyed the Rec. 2020 standard. Zero-dimensional Cs 4 PbX 6 (X = Cl, Br, I) perovskite material is recognized as a potential luminescent material and host owing to its excellent optical properties. However, the synthesis of large-scale CsPbBr 3 /Cs 4 PbBr 6 complex nanocrystals (NCs) is difficult, and their application in mini- or micro-LEDs remains limited. Herein, we applied a microfluidic system for a simple, continuous, and stable synthesis of CsPbBr 3 /Cs 4 PbBr 6 NCs. The CsPbBr 3 /Cs 4 PbBr 6 complex NCs were obtained after the optimization of the Cs/Pb precursor ratio and alkaline environment, and their photoluminescent quantum yield is up to 86.9%. These as-synthesized CsPbBr 3 /Cs 4 PbBr 6 NCs were used to produce a luminescent ink with the optimization of different solvents. This ink was successfully used to print large and high-resolution patterns, and fabricated mini-sized color-converted LED. The narrow green emission of the LED well obeyed the requirements of the Rec. 2020 standard, demonstrating the potential of this material in the inkjet printing applications of color-converted mini- or micro-LED arrays. [ABSTRACT FROM AUTHOR]

[Display omitted] • SLM-manufactured lattice structure geometries exhibit distortion and cluttering. • The lattice distortion is pronounced in upright printed slender geometries. • Unit cells with high nodal connectivity and obtuse angles increase both deficiencies. • The heuristic of reinforcement walls significantly reduces the lattice distortion. • Curvilinear, bio-inspired unit cells diminish both lattice distortion and cluttering. The rapid growth of the geriatric population in industrial societies is expected to increase the demand for prosthetic implants. Unfortunately, current products exhibit shortcomings such as inadequate sizing or excessive material strength both of which hamper the recovery of fractures. Selective laser melting (SLM), as a manufacturing method, is highly suited for optimizing the geometry and topology of products. However, SLM however, seems to restrict the manufacturing precision to mostly horizontal printing which is inefficient when considering the build envelope. Additionally, certain elongated geometries are subject to warpage when printed horizontally. To address these issues, our study investigated the feasibility of vertically oriented porous structures using SLM. It will report on two specific deficiencies, namely slanting and cluttering, that were revealed through X-ray computer tomography. To facilitate the manufacturing of slender, porous structures, the paper will offer and examine heuristics that minimize the defects. The preliminary results indicate that structures such as shell reinforcements and bio-inspired unit cells reduce the occurrence of slanting and cluttering and might serve as interim solutions for the printing of large filigree structures. The general findings suggest that more dedicated research is necessary to understand the relationship between geometrical features and manufacturing precision in SLM. [ABSTRACT FROM AUTHOR]

Research and technological advancements in 3D concrete printing (3DCP) have led to the idea of applying it to offshore construction. The effect of gravity is reduced underwater, which can have a positive effect on 3DCP. For basic verification of this idea, this study printed and additively manufactured specimens with the same mortar mixture in air and underwater and evaluated properties in the fresh state and the hardened state. The mechanical properties were evaluated using the specimens produced by direct casting to the mold and specimens produced by extracting from the additive part through coring and cutting. The results of the experiment show that underwater 3D printing required a greater amount of printing output than in-air 3D printing for a good print quality, and buildability was improved underwater compared to that in air. In the case of the specimen layered underwater, the density and compressive strength decreased compared to the specimen layered in air. Because there are almost no effects of moisture evaporation and bleeding in water, the interlayer bond strength of the specimen printed underwater was somewhat larger than that printed in air, while there was no effect of the deposition time interval underwater. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the effects of print size, typeface, and line width on reading speed in readers with mild to moderate sight problems. Methods: A total of 43 patients, most of whom had mild cataract or glaucoma with acuity 6/30 or better (median age = 72; range = 24–88 years), read aloud a selection of texts presented randomly in four sizes (10, 12, 14 and 16 point), for each of four typefaces [Foundry Form Sans (FFS), Helvetica (HV), Tiresias PCfont (TPC), Times New Roman (TNR)] at a standard line width of 70 characters and a viewing distance of 40 cm. A subset of letter sizes and typefaces were tested at two additional line widths (35, 90). Results: As expected, reading speed increased with print size from a median of 144 words min−1 for 10-point text to 163 words min−1 for 16-point text (repeated measuresanova, p < 0.0001). There was also a significant effect of typeface with TPC being read about 8 words min−1 faster, on average, than the other fonts (159 words min−1 for TPC vs 151 words min−1 for the other fonts, p < 0.0001). However fonts of the same nominal point size were not equivalent in actual size. When adjusted for the actual horizontal and vertical space occupied, the advantage of TPC was eliminated. There was no effect of line width ( p > 0.3). Data from the present study were extrapolated to the general population over age 65. This extrapolation indicated that increasing minimum print size from 10 points to 16 points would increase the proportion of the population able to read fluently (>85 words min−1) from 88.0% to 94.4%. Conclusion: This study shows that line width and typeface have little influence on reading speed in people with mild to moderate sight problems. Increasing the minimum recommended print size from 10 points to 14 or 16 points would significantly increase the proportion of the population able to read fluently. [ABSTRACT FROM AUTHOR]