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Invasive alien plants are detrimentally displacing native plant species and pose a challenge in terms of how their overgrowth can be utilized effectively. In our study, the leaves of one of the world's worst invasive species, Japanese knotweed, were used to produce a green natural dye. This dye was screen-printed onto various substrates, including cotton and polyester fabrics, commercial cellulose papers, and innovative papers made from the stems of Japanese knotweed. The printed substrates were evaluated using color measurements and fastness properties. The aim of the study was also to investigate the influence of additives in the printing inks, such as sodium carbonate, citric acid, copper and aluminum sulfates, on the color and fastness properties of the prints. The colors of the prints obtained varied, ranging from primarily yellowish-green to brownish-yellow with the addition of citric acid, orange-brown with sodium carbonate, orange-yellow with aluminum sulfate, and brown with copper sulfate. The prints had excellent fastness to dry rubbing and moderate fastness to light. The prints of lower and medium dye concentrations on fabrics had very good fastness to wet rubbing and wet ironing, and on cotton even good fastness to washing. The additives in the printing inks, such as sodium carbonate and metal sulfates, reduced the abrasion resistance of the prints on paper and the wet fastness of the prints on fabrics, but only the metal sulfates had a positive effect on the light fastness of the prints. [ABSTRACT FROM AUTHOR]

In this study, we examine the combination of flexible textiles and electrodes to develop electronic textiles (e-textiles). We present a facile fabrication process using printing and coating conductive electrodes. Innovative textiles, which have evolved primarily through the integration of textile and electronic elements, have developed into e-textiles capable of performing high-dimensional tasks. For practical use of e-textiles, however, they should be compatible with various textiles, economical production, and suitable for mass production. In this study, silver ink-carbon nanotubes are used to screen-print electrodes, a key element of e-textile. We verify four types of spandex textiles and analyze whether ink-based electrodes are stably printed on the textile surfaces. As a post-process, 3D printing mold coating is invited to invent durable and water-repellent electrodes. The fabricated e-textile proves its practicality using a washing test. Additionally, electrical measurements under mechanical bending reveal a variety of potential applications based on their properties. As a result, the electrodes of e-textile have an initial electrical resistance of approximately 10 Ω. Polymer coating enhances the reliability of e-textiles. Washing tests and repeated bending deformation demonstrate that they help the coating maintain its electrical conductivity. On the other hand, electrodes without coating lose their electrical capabilities. This study proposes functional materials and reliable manufacturing methods that are beneficial for e-textile production. Accordingly, we present the diversification and potential of the smart textile industry, such as IoT sportswear, medical healthcare clothing, hazardous work detection clothing, and space exploration clothing, which are examples of applications based on e-textile materials and manufacturing technology. [ABSTRACT FROM AUTHOR]

Bean-flour printing is a traditional craft with local characteristics that originated in China. However, its survival today faces various obstacles, especially the lack of innovation. This study has developed a technique to produce multi-color prints on cotton textiles using bean flour and quicklime as pastes and resist agents. It was found that bean flour could be mixed with various natural dyes and colors in the resist part. The thickness of the bean flour pastes had a direct effect on clarity and brightness of the covered area during printing process. In multi-color printing, the hue of the resist area was closely related to the dyes used and the thickness of the bean flour pastes. In addition, the thickness of the bean-flour pastes played a crucial role in rub resistance of the colors and the overall durability of the printed design. In conclusion, this innovative method of multi-color printing not only preserved but also revitalized the ancient art of bean flour printing. [ABSTRACT FROM AUTHOR]

Printing as a process itself generates many environmental concerns. The paper addresses ink management in terms of environmental issues in the label printing industry, focusing on its environmental implications. The goal is to demonstrate how a proper ink management system impacts overall printing process efficiency and environmental sustainability for printing companies. The paper introduces an empirical approach to managing components for label and packaging production, utilizing automatic ink dispensing systems. The results demonstrate that the proper management of ink dispensing to minimize waste in packaging printing is crucial for optimizing operating print costs, potentially reducing the amount of ink needed to prepare colors by 52% and achieving energy savings of 37%. This approach fulfills the goal of sustainability by addressing environmental, economic, and social concerns. By optimizing ink usage and energy consumption, companies can significantly reduce operating costs and enhance economic performance. Simultaneously, these practices improve product quality, meet consumer demands for sustainable packaging, and create better working conditions for employees. Future directions and practical implications for supporting operational excellence in production are also discussed. [ABSTRACT FROM AUTHOR]

The principal goal of this research revolves around imparting antimicrobial activities on printed cotton fabric utilizing silver nanoparticles. Two colorants, dyes, and pigments are used for printing of 100% scoured and bleached cotton, fabric, and both fabrics are assessed to get antimicrobial activity of printed cloth. Screen-printing techniques are used here to apply the pigment and reactive dye onto the fabric. The outcomes of the study reflect that the addition of silver nanoparticles to the reactive dye-printed and pigment-printed fabric significantly decreases bacterial growth up to 99.99%. In addition, Silver nanoparticles increase color intensity by around 25% in pigment printing, however, reduce it in reactive printing. Both methods enhance color fastness by increasing resistance to fading, staining, and rubbing. The scanning electron microscopy (SEM) analysis reveals that the print paste and sodium alginate have an impact on the distribution of nanoparticles. Through X-ray diffraction (XRD), it has been determined that the sample maintains a crystalline form and an average size of 29.185 nm of silver nanoparticles. Fourier Transform Infrared Spectroscopy (FTIR) analysis indicates no notable molecular-level alterations. [ABSTRACT FROM AUTHOR]

The development of three-dimensional (3D) space light angle detection is vital in optical technology for applications such as 3D imaging, computer vision, and augmented reality. Current methods involve advanced sensors and algorithms, including time-offlight cameras, which need multiple cameras and light sources to improve accuracy. However, it is a great challenge to integrate these complex components into compact devices. Subwavelength semiconductor structures offer optical resonance characteristics, enabling precise light–matter interaction regulation. A 3D star-like photodetector, fabricated using a template assistant printing strategy, demonstrates optical resonances of the subwavelength facade and the shielding effect of spatial arrangement. It achieves light angle detection with the resolution of 10° in vertical space and the resolution of 36° in horizontal space, making it a promising prototype for various applications. [ABSTRACT FROM AUTHOR]

Climate change poses a pervasive global threat to humanity, and regrettably, the textile industry stands as the second-largest contributor to greenhouse gas emissions due to its large supply chain. Pollution involves various sub-sectors, including water pollution, where urea emerges as a hazardous chemical detrimental to both human health and aquatic life. This research is dedicated to fostering a sustainable, urea-free approach in the printing of cotton fabric by altering the reactive printing recipe and methodology. Three modified trial recipes (T1, T2, T3) and one controlled conventional recipe (C) were tested. The C included sodium alginate (2%), urea (15%), and sodium bicarbonate (2.5%). In contrast, the modified recipe trials incorporated polyethylene glycol 400 (PEG 400) in the replacement of urea. A total of four recipes (one C and three modified T1 with 1% PEG 400, T2 with 2% PEG 400, T3 with 3% PEG 400 in the printing paste recipes) were examined using two monochlorotrizaine reactive dyes (Reactive C.I. Red 45, Reactive C.I. Violet 01). Characterization like shade variation, dye penetration into the fabric, sharpness of the edges, tinting on the adjacent white fabric, acidic and alkaline perspiration fastness, washing fastness, rubbing fastness, and fabric hardness, affirmed that T2 recipe yielded the best results in fabric testing, cost reduction, and water pollution reduction while increase in the PEG 400 concentration from 2 to 3% have no significant change in the overall results. This research is a contribution in sustainable reactive printing of cellulosic cotton fabric. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to evaluate the safety and effectiveness of three-dimensional (3D)-printed guide plates for assisting in the positioning of the rotation axis of an elbow-hinged external fixator. Methods: Terrible triad (TT) patients, who were screened using the predefined inclusion and exclusion criteria, underwent installation of a hinged external fixator on the basis of internal fixation; 3D-printed guide plates, generated from the patient's imaging data, assisted in positioning the rotation axis. All patients received the same peri-operative management and were followed up at six, 12, 24, and 48 weeks postoperatively. The duration of positioning pin placement, the number of fluoroscopies, pin placement success rate, types and incidence of post-operative complications, and the Mayo elbow performance score (MEPS) of the diseased elbow and range of motion (ROM) of both elbows were assessed. Results: In 25 patients who completed the follow-up, the average time required for positioning pin placement was 329.32 ± 42.38 s (263–443 s), the average number of fluoroscopies was 2.32 ± 0.48 times (2–3 times), and the pin placement success rate was 100%. At the last follow-up, the mean MEPS of the diseased elbow was 97.50 ± 6.92 (75–100), with an excellent and good rate of 100%, and all patients demonstrated stable concentric reduction. The average range of flexion and extension was 135.08° ± 17.10° (77–146°), while the average range of rotation was 169.21° ± 18.14° (108–180°). No significant difference was observed in the average ROM between the both elbows (P > 0.05). Eight (32%) patients developed post-operative complications, including elbow stiffness due to heterotopic ossification in three (12%) patients, all of whom did not require secondary intervention. Conclusion: Utilizing 3D-printed guide plates for positioning the rotation axis of an elbow-hinged external fixator significantly reduced intra-operative positioning pin placement time and the number of fluoroscopies with excellent positioning results. Satisfactory results were also obtained in terms of post-operative complications, elbow ROM, and functional scores. [ABSTRACT FROM AUTHOR]

This study evaluates the effect of herbal extract, mordant and mordanting process on antibacterial activity, color fastness, and durable and comfort properties of the cotton fabric. In the current research, 100% gray cotton fabric, rind of pomegranate, manjistha, and moduga are used. The selected herbals were aqueous extracted and tested for phytochemical screening to find the presence of active ingredients. The cotton fabric is processed, and herbal extracts were applied with standard methods. The dyed materials were tested for antibacterial activity against S. aureus and E. coli and color fastness, durable, and comfort properties. The rind of pomegranate has high antibacterial property, biomass reduction, and excellent color fastness. All the dyed samples showed useful, sustainable, and comfort features. Furthermore, a garment (salwar cum churidar), designed and developed, was analyzed for wear study by 50 students, and they reported that it has excellent comfort and fit. [ABSTRACT FROM AUTHOR]

The results of studies of changes in the diffuse reflection spectra and integral solar radiation absorption coefficient as of a thermal control coating (TCC) of the Optical Solar Reflectors (OSR) class for spacecraft (SCs) under electron irradiation are presented. A dielectric ceramic paste (DCP) consisting of a filler, crushed polycor (Al2O3) and a solvent with a thickener (terpineol with ethyl cellulose), was applied by a 3D printer onto a substrate. Then, heating at 150°C and annealing at 850°C were carried out; a "white" coating was obtained with a high reflection coefficient and a low absorption coefficient, meeting the requirements and standards of the OSR class TCC. The radiation resistance of the resulting DCP-based coating is comparable to the resistance of a highly stable coating based on ZnO pigment with liquid lithium glass and is much higher than the resistance of a plasma-sprayed coating—MgAl2O4 spinel. [ABSTRACT FROM AUTHOR]

Efficient alkali-activated binder pastes of slag and fly ash-based aqueous nano-silica (FABANS) that provide enhanced strength are used for developing extrusion-based 3D printable concretes. The binder pastes of slag made with FABANS are not suitable for printing due to low yield stress and insufficient thixotropic buildup. Rheology control for enhancing the yield stress and thixotropic buildup is evaluated using bentonite clay and carboxymethyl cellulose (CMC). There is a synergistic enhancement in yield stress and thixotropic buildup provided by the combined use of bentonite and CMC that provides improved printability and buildability. Very rapid increase in yield stress with excess clay content in the presence of CMC, however, produces choking of flow and printability loss. Excess CMC results in a Maxwell-type behavior causing shape instability due to continuous relaxation under stress. The proportion of CMC and clay that provides the required thixotropic buildup for buildability is established. Printability and buildability of concrete mixture made with binder paste of FABANS with the proportion of rheology modifiers is demonstrated. [ABSTRACT FROM AUTHOR]

Virtual surgical planning and three-dimensional (D) printing are rapidly becoming essential for challenging and complex surgeries around the world. An Ibero-American survey reported a lack of awareness of technology benefits and scarce financial resources as the two main barriers to widespread adoption of 3-D technologies. The Pereira Rossell Hospital Center is a publicly funded maternal and pediatric academic clinical center in Uruguay, a low-resource Latin American country, that successfully created and has been running a 3-D unit for 4 years. The present work is a step-by-step review of the 3-D technology implementation process in a hospital with minimal financial investment. References to training, software, hardware, and the management of human resources are included. Difficulties throughout the process and future challenges are also discussed. [ABSTRACT FROM AUTHOR]

The possibility of manufacturing a thermal control coating has been studied, and the method of its deposition from PD-12 dielectric paste using a Voltera V-One printer has been considered. The morphology, surface roughness, phase structure, diffusion reflection spectra in the range of 200–2500 nm, integral sunlight absorbance, and IR spectra in the range of 400–4000 cm–1 of the coating are investigated. It is established that the proposed method of paste deposition using the printer with its subsequent heating and burning into a substrate allows manufacturing of thermal control dielectric coatings with the reflectance close to that of the well-known coatings of the optical solar absorber class. The results obtained can be used in other fields of science and technology. [ABSTRACT FROM AUTHOR]

With the advent of printed electronics, electrode manufacturing has made significant progress. In contrast to the traditional lift-off method, printing methods offer several advantages. They are not limited by the shape, structure, or material of the substrate, allowing for the manufacturing of electrodes using a wider range of materials. The manufacturing process can be completed at low temperatures, and the cost is reduced due to less material consumption. Printing methods can be broadly categorized into plate printing and plateless printing. Screen printing is a representative plate printing method, while inkjet printing is a typical plateless method. The two techniques are widely used in electrode manufacturing due to their convenience and the easily customized graphics. Screen printing is particularly efficient for processing electrodes in large quantities, while inkjet printing offers greater flexibility, allowing for quick adjustments to the shape of electrodes. This paper reviews recent advances in electrode manufacturing based on printing, focuses on the characteristics of screen printing and inkjet printing, and makes discussions about the main issues and challenges and the potential solutions. [ABSTRACT FROM AUTHOR]

This technical innovation assesses the adaptability of some common automated segmentation tools on abnormal pediatric magnetic resonance (MR) brain scans. We categorized 35 MR scans by pathologic features: (1) "normal"; (2) "atrophy"; (3) "cavity"; (4) "other." The following three tools, (1) Computational Anatomy Toolbox version 12 (CAT12); (2) Statistical Parametic Mapping version 12 (SPM12); and (3) MRTool, were tested on each scan—with default and adjusted settings. Success was determined by radiologist consensus on the surface accuracy. Automated segmentation failed in scans demonstrating severe surface brain pathology. Segmentation of the "cavity" group was ineffective, with success rates of 23.1% (CAT12), 69.2% (SPM12) and 46.2% (MRTool), even with refined settings and manual edits. Further investigation is required to improve this workflow and automated segmentation methodology for complex surface pathology. [ABSTRACT FROM AUTHOR]

Purpose: To address the anatomical challenges facing complex and revision spinal surgery, patient-specific 3D-printed models (3D-PMs) have received growing attention worldwide, primarily in adults. We report the use of a 3D-PM in the treatment of a case of wound breakdown over a component of a VEPTR (Vertical Expandable Prosthetic Titanium Rib; DePuy-Synthes) system, requiring replacement of Dunn-McCarthy hook and sleeve with components contoured to a patient-specific 3D-PM of the spine. Method: A two-year-old born with myelomeningocele (MMC), repaired at birth, developed progressive MMC-associated kyphoscoliosis. Elective insertion of a rib-to-pelvis 'Eiffel Tower' bilateral VEPTR growing rods construct was performed without initial complication. Prominence of the right VEPTR sleeve and Dunn-McCarthy hook side-to-side connector resulted in breakdown of overlying poor-quality soft tissues, necessitating washout, partial implant removal, intravenous antibiotic therapy and delayed primary wound closure. A patient-specific 3D-PM, utilising pre-operative CT spine and pelvis 3D-reconstructions, allowed pre-operative formation of a contoured implant, which was inserted without need for further revision. Results: The patient underwent further VEPTR lengthening without recurrent infection, wound breakdown or implant failure at 24-month follow-up. Satisfactory control of the deformity has been achieved with continued improvement in sitting height and radiographic indices. Conclusion: This case illustrates the possibility, in certain cases, of using 3D-PM to develop complex components of spinal implant systems pre-operatively, removing the time and difficulty of intra-operative contouring. Consequently, custom-contoured implants may be produced, sterilised and implanted. This technique may be an option, in infants, including MMC-associated kyphoscoliosis, where midline fixation is not possible. [ABSTRACT FROM AUTHOR]

African Lusophone literatures are largely a Portuguese product: the very construction of literary corpora though book editing and printing was mainly led by Portuguese publishers before and after independence. Other non-African institutions (universities, literary agents, critics) were largely responsible for that process of canonization in the Portuguese-speaking world, with repercussions in Africa itself. In the worlding of these already constituted African literary archives through translation, the grip of European agencies is even stronger: more than half of the published translation passes through the mediation of a single, Frankfurt-based literary agency. More than half of these books were funded by a translation support programme paid for by the Portuguese state. In this state of affairs, this article wishes to carry out a reflection on the institutional situation in which such literatures are produced, appear in book form and travel inside and outside the Portuguese-language literary space(s). It is my opinion, following and adapting Pascale Casanova's suggestion, that a single literary work, in this specific case, can assume a threefold position: a national one, a specific position inside the Portuguese-language literary space and, finally, a world-literary one, thus oscillating between the dimension of nation-state, the post-imperial language community and the World Republic of Letters. I will resort to two case studies, exemplary of two divergent trajectories: José Eduardo Agualusa, possibly the most resonant example of internationalisation of an Angolan author; and João Melo, which appears to have a stronger national positioning and a much weaker international one. [ABSTRACT FROM AUTHOR]

Purpose: The use of two-dimensional (2D) printing technologies of drugs on orodispersible films (ODF) can promote dose individualization and facilitate drug delivery in vulnerable patients, including children. We investigated midazolam pharmacokinetics after the administration of 2D-printed ODF. Methods: Midazolam doses of 0.03 and 3 mg were printed on an ODF using a 2D drug printer. We investigated the bioavailability of the two midazolam doses with ODF swallowed immediately (ODF-IS) or delayed after 2 min (ODF-DS) by comparing their pharmacokinetics with intravenous and oral midazolam solution in 12 healthy volunteers. Results: The relative bioavailability of ODF-IS 0.03 mg was 102% (90% confidence interval: 89.4–116) compared to oral solution and for 3 mg 101% (86.8–116). Cmax of ODF-IS 0.03 mg was 95.5% (83.2–110) compared to oral solution and 94.3% (78.2–114) after 3 mg. Absolute bioavailability of ODF-IS 0.03 mg was 24.9% (21.2–29.2) and for 3 mg 28.1% (23.4–33.8) (oral solution: 0.03 mg: 24.4% (22.0–27.1); 3 mg: 28.0% (25.0–31.2)). Absolute bioavailability of ODF-DS was significantly larger than for ODF-IS (0.03 mg: 61.4%; 3 mg: 44.1%; both p < 0.0001). Conclusion: This trial demonstrates the tolerability and unchanged bioavailability of midazolam printed on ODF over a 100-fold dose range, proving the suitability of ODF for dose individualization. Midazolam ODF-IS AUC0–∞ in both doses was bioequivalent to the administration of an oral solution. However, Cmax of the therapeutic dose of ODF-IS missed bioequivalence by a clinically not relevant extent. Prolonged mucosal exposure increased bioavailability. (Trial Registration EudraCT: 2020–003984-24, August 10, 2020). [ABSTRACT FROM AUTHOR]

Most natural thickeners do not have a full coverage degree when printing on dark dyed fabrics (brown/navy/black). Therefore, some materials are added to improve their coverage. It is common practice that printing is done on dyed or undyed fabrics. The dyed fabrics are of different shades, so the printing process faces a problem, as most of the natural thickeners do not have full coverage, especially those extracted from aloe vera and flax seeds when printing on fabrics dyed with dark colors. Therefore, in this study the effect of adding zinc oxide and titanium oxide to the printing paste was studied. The result confirmed that, adding metal salts to printing paste using aloe vera gel or flaxseeds gum as thickener increases the whiteness index of these pastes as well as the printed fabric. In addition, using light dye in these printing paste provides good covering of dark color with good appearance of the new light color used. Furthermore, the mechanical and physical characteristics of printed textiles with various thickeners and metal oxide (14 %) have been evaluated and provide improving both tensile strength and elongation at break and had no effect on the angle of crease recovery of printed textiles across all printing paste formulations. [ABSTRACT FROM AUTHOR]

The particulate matter (PM) emitted by printers during printing pollute the indoor air, which can pose a health hazard for the people indoors. The source strength, decay characteristics, and mechanism of the PM emitted by printers were studied. A sealed chamber was used for printing experiments, and the particle number concentrations were monitored in real time using an Electrical Low-Pressure Impactor (ELPI+). Our findings highlight the negative impact of printing on the indoor environment. The printers directly emitted particles covering three size ranges: 15.8–94.5 nm, 94.5–313 nm, and 313–949 nm. The emission rates of PM0.1 and PM0.1-1 by the printers were 1.57×108–53.83×108/min and 3.46×108–143.81×108/min, respectively. The printer and the amount of toner used both affected the emission of particles, especially PM0.1-1. The particles emitted were mostly decayed within 1 h after printing; moreover, the decay of PM0.1-1 was slower than that of PM0.1. The decay rates of PM0.1 were 0.016–0.083/min in the 0–30 min period and approached 0 in the 30–60 min period. The decay rates of PM0.1-1 were 0.015–0.127/min within 60 min after printing and differed little across periods. One hour after printing, all but a very small proportion of particles measuring 54.5–94.5 nm was decayed in the chamber, indicating that particles of that size were decayed with greater difficulty. [ABSTRACT FROM AUTHOR]

We conducted a comprehensive review of surgical simulation models used in robotic surgery education. We present an assessment of the validity and cost-effectiveness of virtual and augmented reality simulation, animal, cadaver and synthetic organ models. Face, content, construct, concurrent and predictive validity criteria were applied to each simulation model. There are six major commercial simulation machines available for robot-assisted surgery. The validity of virtual reality (VR) simulation curricula for psychomotor assessment and skill acquisition for the early phase of robotic surgery training has been demonstrated. The widespread adoption of VR simulation has been limited by the high cost of these machines. Live animal and cadavers have been the accepted standard for robotic surgical simulation since it began in the early 2000s. Our review found that there is a lack of evidence in the literature to support the use of animal and cadaver for robotic surgery training. The effectiveness of these models as a training tool is limited by logistical, ethical, financial and infection control issues. The latest evolution in synthetic organ model training for robotic surgery has been driven by new 3D-printing technology. Validated and cost-effective high-fidelity procedural models exist for robotic surgery training in urology. The development of synthetic models for the other specialties is not as mature. Expansion into multiple surgical disciplines and the widespread adoption of synthetic organ models for robotic simulation training will require the ability to engineer scalability for mass production. This would enable a transition in robotic surgical education where digital and synthetic organ models could be used in place of live animals and cadaver training to achieve robotic surgery competency. [ABSTRACT FROM AUTHOR]

Purpose: Spine surgery entails a wide spectrum of complicated pathologies. Over the years, numerous assistive tools have been introduced to the modern neurosurgeon's armamentarium including neuronavigation and visualization technologies. In this review, we aimed to summarize the available data on 3D printing applications in spine surgery as well as an assessment of the future implications of 3D printing. Methods: We performed a comprehensive review of the literature on 3D printing applications in spine surgery. Results: Over the past decade, 3D printing and additive manufacturing applications, which allow for increased precision and customizability, have gained significant traction, particularly spine surgery. 3D printing applications in spine surgery were initially limited to preoperative visualization, as 3D printing had been primarily used to produce preoperative models of patient-specific deformities or spinal tumors. More recently, 3D printing has been used intraoperatively in the form of 3D customizable implants and personalized screw guides. Conclusions: Despite promising preliminary results, the applications of 3D printing are so recent that the available data regarding these new technologies in spine surgery remains scarce, especially data related to long-term outcomes. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the long-term safety and efficacy of a 3D-printed bioresorbable polycaprolactone (PCL) nasal implant for nasal septal deformity reconstruction. Methods: Fourteen patients who had undergone nasal septum reconstruction surgery using 3D-printed PCL nasal septal implants were enrolled. The primary outcome was the change in total Nasal Obstruction Symptom Evaluation (NOSE) scale scores between postoperative 3 months and current status (3.59 ± 0.51 years). The secondary outcomes were changes in the minimum cross-sectional area (MCA) and volume of both nasal cavities based on acoustic rhinometry, the cross-sectional area of the ostiomeatal unit, and the nasal septum angle of the paranasal sinus (PNS) in computed tomography (CT) images, and a visual analog scale (VAS) of the patients' subjective satisfaction. Results: The results showed no significant changes in the MCAs (Cohen's d:0.09; p = 0.711) or nasal volume (Cohen's d:0.26; p = 0.356), the area of the ostiomeatal unit (Cohen's d:0.49; p = 0.064), septum angles (Cohen's d:0.18; p = 0.831), the NOSE scale (Cohen's d:0.14; p = 0.621), or patients' subjective satisfaction (Cohen's d:0.52; p = 0.076) during the follow-up period. Conclusions: This homogeneous composite microporous PCL nasal septal implant demonstrated long-term clinical efficacy and safety in human tissues that required maintenance of mechanical strength. Therefore, the indications for this implant could extend to various other craniofacial reconstructions in the future. [ABSTRACT FROM AUTHOR]

Solvent-free inorganic-organic hybrid polymers were prepared for digital light processing (DLP) and ink-jet printing. The resins were characterized in terms of viscosity, surface tension, and refractive index. Optical bulk components were prepared with both printing techniques and compared regarding their surface roughness and optical scattering. The haze of DLP-samples can be avoided by inkjet 3D printing. Moreover, different quantum dots (QD) could be incorporated into resins; DLP resulted in complex 3D assemblies. Highlights: Synthesis of solvent-free inorganic-organic hybrid resins. Viscosity and surface tension suitable for DLP and ink-jet technology. Quantum dots can be incorporated to result in functional composites. Printing of bulk optical components. [ABSTRACT FROM AUTHOR]

This paper describes the research, development and prototype of an electro-mechanic electrical discharge plotter system based on a three-axis Cartesian robot. The plotter can trace monochromatic arbitrary figures or alphanumeric characters on a given substrate such as paper without using any ink. A discharge probe delivering controlled electrical discharges is moved on the two-dimensional surface of the substrate using stepper motor-driven linear actuators to generate the arbitrary figures similar to CNC-based laser cutters and EDMs. The heat of the plasma evolved during the dielectric breakdown of ambient air during an electrical discharge or an arc has been used to create dark spots on the substrate by surface carburization. The discharge pulse duration, electrical parameters and the actuator movement are controlled by a microcontroller. The common printing systems currently available in the market give 300 to 600 DPI of resolution. However, the plotter prototype featured in this article plots with a resolution of 60 to 80 DPI which is enough to demonstrate. This technology can potentially eliminate the need for inks and toners which need frequent refilling. Every refilling invites considerable expenditure and significant environmental impact when their containing cartridges are discarded. This article only intends to put forward the possibility of such a printing technique and not propose the perfect alternative for existing printing systems. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) printing of vascular structures is of special interest for procedure simulations in Interventional Radiology, but remains due to the complexity of the vascular system and the lack of biological tissue mimicking 3D printing materials a technical challenge. In this study, the technical feasibility, accuracy, and usability of a recently introduced silicone-like resin were evaluated for endovascular procedure simulations and technically compared to a commonly used standard clear resin. Fifty-four vascular models based on twenty-seven consecutive embolization cases were fabricated from preinterventional CT scans and each model was checked for printing success and accuracy by CT-scanning and digital comparison to its original CT data. Median deltas (Δ) of luminal diameters were 0.35 mm for clear and 0.32 mm for flexible resin (216 measurements in total) with no significant differences (p > 0.05). Printing success was 85.2% for standard clear and 81.5% for the novel flexible resin. In conclusion, vascular 3D printing with silicone-like flexible resin was technically feasible and highly accurate. This is the first and largest consecutive case series of 3D-printed embolizations with a novel biological tissue mimicking material and is a promising next step in patient-specific procedure simulations in Interventional Radiology. [ABSTRACT FROM AUTHOR]

All-polymer solar cells (all-PSCs) trigger enormous commercial applications, and great progress has been made in recent years. However, from small-area devices to large-area modules, the poor adaption of the materials for printing methods and the large efficiency loss are still great challenges. Herein, three novel non-conjugated polymer acceptors (PTH-Y, PTClm-Y and PTClo-Y) are developed for all-PSCs. It can be found that non-conjugated polymer acceptors can effectively minimize the technique and efficiency gaps between small-area spin-coating and large-area blade-printing method, which can facilitate the preparation of large-area flexible device. By directly inheriting the spin-coating condition, the blade-coating processed device based on PTClo-Y achieves an impressive power conversion efficiency (PCE) of 12.42%, comparable to the spin-coating processed one (12.74%). Such a non-conjugated polymer system also can well tolerate large-scale preparation and flexible substrate. Notable PCE of 11.94% for large-area rigid device and 11.56% for large-area flexible device are obtained, which is the highest value for large-area flexible all-PSCs fabricated by blade-coating. In addition, the non-conjugated PTClo-Y-based devices show excellent thermal stability and mechanical robustness. These results demonstrate that the non-conjugated polymer acceptors are potential candidates for the fabrication of highly-efficient, large-area and robust flexible all-PSCs by printing methods. [ABSTRACT FROM AUTHOR]

Printing is a promising method for the large-scale, high-throughput, and low-cost fabrication of electronics. Specifically, the contact printing approach shows great potential for realizing high-performance electronics with aligned quasi-1D materials. Despite being known for more than a decade, reports on a precisely controlled system to carry out contact printing are rare and printed nanowires (NWs) suffer from issues such as location-to-location and batch-to-batch variations. To address this problem, we present here a novel design for a tailor-made contact printing system with highly accurate control of printing parameters (applied force: 0–6 N ± 0.3%, sliding velocity: 0–200 mm/s, sliding distance: 0–100 mm) to enable the uniform printing of nanowires (NWs) aligned along 93% of the large printed area (1 cm2). The system employs self-leveling platforms to achieve optimal alignment between substrates, whereas the fully automated process minimizes human-induced variation. The printing dynamics of the developed system are explored on both rigid and flexible substrates. The uniformity in printing is carefully examined by a series of scanning electron microscopy (SEM) images and by fabricating a 5 × 5 array of NW-based photodetectors. This work will pave the way for the future realization of highly uniform, large-area electronics based on printed NWs. [ABSTRACT FROM AUTHOR]

Excessive overgrowth of an invasive alien plant like Japanese knotweed is an ecological problem that threatens the ecosystem and reduces biodiversity. However, it can be potentially used for various beneficial purposes, e.g. for the production of paper or natural dyes, as a renewable and sustainable resource. In our research, the orange extract of the Japanese knotweed rhizome was used as a natural dye for the formulation of screen printing inks. The prepared printing inks with different dye concentrations were printed by flat screen printing technique on two papers made of Japanese knotweed stem and on two commercial papers as well as on cotton and polyester fabrics. The color of the prints was evaluated spectrophotometrically and the fastness of the printing inks on different printing materials was analyzed. The research results confirmed the usefulness of the natural dye derived from the Japanese knotweed rhizome for printing, especially on papers whose prints showed very good rub resistance. However, its application for printing on textiles is limited due to its lower fastness to wet treatments such as washing, wet rubbing, and wet ironing. The natural dye is resistant to fading under the influence of light, but its color becomes darker. When exposed to light, yellow prints darken to orange-brown prints, which are more pronounced at higher dye concentrations; however, this could be an interesting effect on printed products. [ABSTRACT FROM AUTHOR]

Dual-purpose coated paper, which enables in-line inkjet printing with web offset, can be used for both offset and inkjet prints. This product has potential to meet the ever-increasing demand for printing individualized information on commercial printing materials. In this work, commercial samples were printed in the two presses. It was deduced that low permeability correlates with large color gamut volume. The correlation would be useful to design coating formulations for good printability. Also, we examined the packing of coating layers to identify a coating formulation that provides good printing quality in both offset and inkjet printing. Many combinations of pigments were tested, and the effects of particle shape on viscosity and packing were examined. For all coating colors, pigment mixtures with a weight ratio of 3:1 gave the highest packing density. The mixture of GCC 90 and delaminated clay with a weight ratio of 3:1 was the best selection studied for dual-purpose coated paper. Among commercial paper samples, a web offset coated paper showed the best overall performance, indicating that coating formulations with minimal blistering are suitable for dual-purpose coated paper. [ABSTRACT FROM AUTHOR]

Colored polymer nanospheres have high light absorption, reflection, and color properties, which can be widely used as the colorants in inks, textiles, and paints. In this paper, the monodispersed cationic colored polymer nanospheres (RCCM, YCCM, and BCCM) with the three-primary colors were fabricated by emulsion polymerization using polymerizable dyes (AHAQ, AAQBC, and AHMAQ) and styrene (St) as the monomers. The polymerizable dyes were successfully synthesized, and their chemical structures were characterized by 1H-NMR, FT-IR, and elemental analysis. The diameters and zeta potential of RCCM, YCCM, and BCCM were 65 nm, 68 nm, 69 nm, and + 42.8 mV, + 45.3 mV, and + 50.6 mV, respectively. Importantly, the prepared nanospheres exhibited high dispersion stability due to their high zeta potential. Then the RCCM, YCCM, and BCCM were applied to CMC-treated cotton fabric printing without any extra additives. The printed fabrics exhibited a certain hydrophobicity with the contact angles (CA) of 125°, 128°, and 123°. The testing of hand feel indicated that the hand feel of printed fabrics changed slightly as compared with cotton fabrics. And the color fastness of all printed fabrics was good enough for practical applications. [ABSTRACT FROM AUTHOR]

Over the last several decades, colloidal quantum dots (QDs) have been widely studied because of their unique optical and electronical properties such as band gap tunability, extremely high color purity, and efficient light absorption and emission. Consequently, they have been regarded as promising materials for next-generation optoelectronic devices such as displays, image sensors, and solar cells. Because these devices employ solid state forms of colloidal QD ensembles, the development of the processes that can tailor their 3D architecture is essential. Here, this review article explores the recent progress of the high-resolution printing techniques for colloidal QDs. Specifically, we present a wide range of methods including photolithography, inkjet printing, nanoimprinting, and transfer printing. We also discuss how these printing methods have been inspired by the patterning techniques for polymer-based materials. [ABSTRACT FROM AUTHOR]

Detrimental corrosion is an ever-concerning challenge for metals and alloys. One possible remedy is to apply organic corrosion inhibitors. Despite progress in molecular assembly and inhibitor research, better mechanistic insight on the molecular level is needed. Here we report on the behavior of well-defined artificial molecular interfaces created by micro-contact printing of thiol-inhibitor molecules and subsequent backfilling. The obtained heterogeneity and defects trigger localized dealloying-corrosion of well-defined Cu3Au surfaces. The stability of applied inhibitor molecules depends on alloy surface morphology and on intermolecular forces of the molecular layers. On extended terraces, dealloying preferentially starts at the boundary between areas composed of the two different chain-length inhibitor molecules. Inside of the areas hardly any nucleation of initial pits is visible. Step density strongly influences the morphology of the dealloying attack, while film heterogeneity avoids cracking and controls molecular-scale corrosion attack. The presented surface-science approach, moreover, will ultimately allow to verify the acting mechanisms of inhibitor-cocktails to develop recipes to stabilize metallic alloy surfaces. [ABSTRACT FROM AUTHOR]

To improve the accuracy of color reproduction for camouflage printing, a new color matching method, named monitor-paper-fabric, was proposed by importing color management into textiles, which matched the printing pastes according to the color of the paper card printed by the ink-jet printer after color management. Not like the traditional color matching method, it matched the printing pastes according to the color from computer monitor after color correction. Two color matching methods were analyzed by comparing the color difference. It was found that the "monitor-paper-fabric" color matching method could be considered as a convenient and feasible color matching method. Most color differences between the monitor and the fabric in the camouflage pattern were reduced to lower than 4, except for color blocks 5 and 6. In addition, the color differences of six color blocks between the paper and the fabric were all less than 3.5, and were lower than those between the monitor and the fabric. The color consistency between the paper and the fabric was better than that between the monitor and the fabric. [ABSTRACT FROM AUTHOR]

Fine line screen printing for solar cell metallization is one of the most critical steps in the entire production chain of solar cells, facing the challenge of providing a conductive grid with a minimum amount of resource consumption at an ever increasing demand for higher production speeds. The continuous effort of the industrial and scientific community has led to tremendous progress over the last 20 years, demonstrating an average reduction rate for the finger width of approximately 7 µm per year with the latest highlight of achieving widths of 19 µm. However, further reductions will become a major challenge because commonly used metal pastes are not able to penetrate arbitrary small screen opening structures. Therefore, this study introduces the novel dimensionless parameter screen utility index SUI which quantifies the expected printability of any 2-dimensional screen architecture in reference to a given paste. Further, we present a full theoretical derivation of the SUI, a correlation to experimental results and an in-depth simulation over a broad range of screen manufacturing parameters. The analysis of the SUI predicts the point when commonly used wire materials will fail to provide sufficient meshes for future solar cell metallization tasks. Therefore, novel wire materials (e.g. the use of carbon nanotubes) with very high ultimate tensile strengths are discussed and suggested in order to fulfill the SUI requirements for printing contact fingers with widths below 10 µm. We further analyze economic aspects of design choices for screen angles by presenting an analytical solution for the calculation of mesh cutting losses in industrial screen production. Finally, we combine all aspects by presenting a generalized approach for designing a 2-dimensional screen architecture which fulfills the task of printing at a desired finger width. [ABSTRACT FROM AUTHOR]

Waste textiles generally have various colours. The largely discarded textiles not only result in huge loss of the limited natural materials, but also waste the colour in it which had cost substantial energy consumption and risked water pollution during dyeing. This work aimed to recycle both the waste textiles and the colours in them. In this research, magenta waste cotton fabric was firstly milled into powders with different particle sizes, and then printed as "pigments" onto cotton fabric to achieve new magenta coloured fabrics. Properties of the powders and corresponding printed fabrics were tested, including powder morphology, colour and fabric colour fastness. Powders with different particle sizes showed different colour depth from the K/S and L*a*b* value results. The K/S value of printed fabrics indicated that particle size did not have an apparent influence on the fabric colour. Furthermore, fabrics printed with 2, 5, 10 and 30 µm magenta cotton powders presented good fastness, among which the fabric printed with 5 µm powders possessed the best colour and rub fastness. This study demonstrated a potential new application for coloured textile waste. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of our study was to improve the minor asymmetries of fronto-orbital advancement (FOA) by introducing a simple model to guide the FOA in unicoronal synostosis which may help saving time and cost. Methods: A retrospective analysis of 16 consecutive patients with unicoronal synostosis corrected by FOA guided by a guide model. Patients with syndromic craniosynostosis or associated craniofacial anomalies were excluded from the analysis. In all cases, 3D mirror image models were used for guiding unilateral fronto-orbital advancement. Demographic, perioperative, and follow-up data were collected for comparison. Cranial and orbital volumes were documented preoperatively and postoperatively and compared with the non-synostotic side. The postsurgical appearance of the face was documented photographically and then evaluated and scored using the Whitaker scoring system. Results: The study included nine males and seven females. The mean age of the patients at the time of the operation was 20.4 months. The mean follow-up duration was 36 months. Mean operative time was 170 min, mean anesthetic time was 230 min, mean blood loss was 50–80 ml, and the average hospital stay was 4.4 days. No relapse that required surgical correction was reported. There were improvements in the orbital indices and volume to be near equal to the normal side. Excellent to good results were obtained in all patients according to the Whitaker classification system. Conclusion: Residual deformity after FOA mandates another tool to optimize the results. Our study introduced a simple, easy, and applicable method to guide the FOA with lesser asymmetries. [ABSTRACT FROM AUTHOR]

Anionic dyes are often used for conventional cotton dyeing. This process, however, has a moderate affinity and it is estimated that less than 70% of the dye interacts with the cotton fiber. Cationization of cellulose is a chemical treatment that modifies the cellulose molecule, making it strongly cationic. This pretreatment increases the affinity between cotton and anionic dyes. Therefore, cationic dyeing reduces water, time, energy and chemical consumption. In this scenario, there is a growing demand to develop new cleaner products, as well as to elucidate the reaction mechanism aiming to create a clean and low-cost process for cotton cationization. In the last decades, more than 800 documents were published, and this number continues to rise. Among the cationic agents, 3-chloro-2-hydroxypropyl trimethylammonium chloride is the most researched and has achieved niche markets. However, poly-diallyldimethylammonium chloride combines effectiveness with a cleaner process. These characteristics make this cationic agent promising for future research. This review reports the state of the art on the techniques used for cationization, with a brief description of the market available for cationic cotton and a critical evaluation of the future perspectives for cationization. [ABSTRACT FROM AUTHOR]

This study represents a successful and simple method for printing and finishing polyester fabrics by adapting a new aminothiazole disperse dye and microwave technique. Microwave pretreatment of polyester fabrics was carried out under a variety of conditions in terms of the microwave power and time. Afterwards, the printed samples were fixed using both conventional techniques and microwave energy. The color strength expressed as K/S of the printed samples was evaluated in addition to CIELAB coordinates (L*, a*, and b*), which were also measured. Washing, rubbing, and light fastness properties were evaluated for samples prepared by both conventional and microwave fixation techniques. Scanning electron microscopy (SEM) was used to investigate the morphological characteristics of the treated printed samples. The biological activity of the synthesized dye against gram-positive bacteria and gram-negative bacteria was also evaluated. The obtained results clarified that the prints obtained using microwave treatment and new dyes have better color strength, stable brilliant color, good fastness properties, and highly durable antibacterial activity when compared to those of conventional techniques using thermofixation and steaming. [ABSTRACT FROM AUTHOR]

The article expands history of patristic printing in the Sixteenth and Seventeenth centuries. It mentions that as censorship came into greater force, printers devised new ways to ensure that their editions of the Church Fathers could be sold on a multi-confessional market. It also informs on neglected peripheries of the republic of letters, whether small presses in the Holy Roman Empire and France, or libraries and scholars in Italy, England, and Spain.

Continuous 3+2-axis additive manufacturing (AM) is an emerging AM technology that overcomes the signature problems of the need of support structures and the staircase effect of the traditional 3-axis AM. This paper presents a novel process planning framework for automatically generating a multi-axis support-free printing path for continuous 3+2-axis AM of an arbitrary freeform part. The framework is based on the geometric processing of skeletonization and decomposition and is particularly suitable for a part with distinct multiple trunk-branch structures. The physical printing experimental results carried out by the authors indicate that the proposed framework has performed well and fabricated some challenging models with large overhangs and twisty spatial topologies. [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrid perovskite solar cells have generated wide interest due to the rapid development of their photovoltaic conversion efficiencies. However, the majority of the reported devices have been fabricated via spin coating with a device area of < 1 cm2. In this study, we fabricated a wide-bandgap formamidinium lead bromide (FAPbBr3) film using a cost-effective, high-yielding doctor-blade-coating process. The effects of different surfactants, such as 1-α-phosphatidylcholine, polyoxyethylene sorbitan monooleate, sodium lauryl sulfonate, and hexadecyl trimethyl ammonium bromide, were studied during the printing process. Accompanying the optimization of the blading temperature, crystal sizes of over 10 µm and large-area perovskite films of 5 cm × 5 cm were obtained using this method. The printed FAPbBr3 solar cells exhibited a short-circuit current density of 8.22 mA/cm2, an open-circuit voltage of 1.175 V, and an efficiency of 7.29%. Subsequently, we replaced the gold with silver nanowires as the top electrode to prepare a semitransparent perovskite solar cell with an average transmittance (400–800 nm) of 25.42%, achieving a high-power efficiency of 5.11%. This study demonstrates efficient doctor-blading printing for preparing large-area FAPbBr3 films that possess high potential for applications in building integrated photovoltaics. [ABSTRACT FROM AUTHOR]

In offset printing process, poor mechanical properties and printability of paper substrate usually result in printing problems, low quality of print and waste of paper materials. Therefore, many researches focus on the quality improvement of paper substrates using suitable additives. In this work, N-methylated chitosan, including N, N-dimethyl chitosan (DMC) and N, N, N-trimethyl chitosan (TMC), were prepared and employed as coating agents to ameliorate the mechanical properties and printability of paper sheets. Analysis results showed that the mechanical strength of coated papers with DMC and TMC were largely improved, because the fibers with negative charges were prone to form electrostatic bonding with the positively charged N-methylated chitosan, thus enhancing paper strength. Particularly, compared with chitosan and DMC, the TMC-coated paper exhibited better mechanical properties, printability and surface properties due to the high cationic charge density of TMC. Therefore, surface coating with TMC is of great benefit to decrease the printing problem of paper sheets and enhance the operation speed in offset printing. This work provides a valuable reference for the amelioration of the printability and physical properties of high-quality paper products for many promising applications. [ABSTRACT FROM AUTHOR]

Printed electronics enable the fabrication of large-scale, low-cost electronic devices and systems and thus offer significant possibilities in terms of developing new optoelectronic application in various fields. Organic photodetectors (OPDs) represent an emerging organic optoelectronic device, which have attracted extensive attention due to many advantages such as low cost, mechanical flexibility and chemical tailoring. Herein, flexible bulk heterojunction (BHJ) OPDs are fabricated on polyethylene terephthalate (PET) substrate by large-scale roll-to-roll (R2R) micro-gravure printing technique using the novel printable ink, which consists of a conjugated polymer named PBDB-T and a nonfullerene small molecule named IT-M. The device photoresponse covers the range from ultraviolet (UV) to visible light (Vis). Meanwhile, OPDs show a high photoresponsivity (R) up to 4.18 A/W and a good detectivity (D*) as high as 1.11 × 1011 Jones. Under the different bending curvature or after being bent 5000 times, the flexible OPDs still well maintain the performance parameters. Furthermore, the large-area OPD arrays exhibit good uniformity and high stability in atmospheric conditions without any encapsulation for 40 days. This work reports the high-quality PBDB-T/IT-M BHJ used for UV–Vis photodetectors, which provides an innovation pathway to develop high-performance, flexible OPDs processed via large-scale, low-cost R2R printing technique. [ABSTRACT FROM AUTHOR]

Manufacturing an array of high-quality metallic pattern layers on a dielectric substrate remains a major challenge in the development of flexible and 3-D frequency selective surfaces (FSS). This paper proposes an improved fabrication solution for the 3-D FSS based on water transfer printing (WTP) technology. The main advantages of the proposed solution are its ability to transform complicated 2-D planar FSS patterns into 3-D structures while improving both manufacturing quality and production costs. WTP technology makes use of water surface tension to keep the thin metallic patterns of the proposed FSS floating flat with the absence of a solid planar substrate. This feature enables these metallic FSS patterns to be transferred onto 3-D structures through a dipping process. To test the effectiveness of the proposed technique, the FSS was designed using computer simulation software Microwave Studio to obtain the numerical performance of the FSS structure. The WTP technology was then used to fabricate the proposed FSS prototype before its performance was tested experimentally. The measurement results agreed well with the numerical results, indicating the proposed manufacturing solution would support the development of complicated 3-D electronics devices, such as conformal antenna arrays and metamaterials. [ABSTRACT FROM AUTHOR]

Although 3D printing was invented in 1984, it was not until recent years that it captured the imagination of everyone from industry experts to at-home hobbyists. Three-dimensional printing, also known as additive manufacturing or rapid prototyping, constructs an object by accumulating materials layer by layer. In recent years, 3D printing technology has been dramatically developed with respect to materials, printer, and process, which laid a foundation for 4D printing. Four-dimensional printing is the targeted evolution of the 3D-printed structure, concerning shape, property, and functionality. The object is produced by 3D printing firstly. Then, the object can self-deform, self-assemble, self-disassemble, self-repair, and change property or functionality over time when the external stimuli are imposed on it. This review mainly introduces the stimulus, types of shape-shifting behaviors, mechanisms of deformation, and applications of 4D printing. [ABSTRACT FROM AUTHOR]

Methods for stereolithographic printing of novel geometries and materials were investigated using 198Au doped commercially available resins. Test coupons were printed to find the specific activity and homogeneity of radionuclides throughout the medium. Initial trials of the technology were used to print pellets with 198Au specific activities with an average of 2.74 × 102 ± 2.9% Bq g−1 to 6.7 × 10−1 ± 11.6% Bq g−1. Mixing qualities varied from 0.99 to 0.91. Geometric shapes were printed to probe the source-geometry sensitivity of the gamma detection apparatus. This manuscript serves as proof of concept for the technique. [ABSTRACT FROM AUTHOR]

Due to the strong demand for low-cost and highly efficient products, various approaches are currently being explored and applied so as to contribute to the development and optimization of 4D printing technology. Significant progress is being made in this area of advanced manufacturing, and this comparative study helps to understand the latest developments in materials, additive techniques, and future prospects for this technology. It should, however, be noted that a large amount of progress still remains to be made. While some of the research has focused on the performance of the materials, the rest has focused on the development of new methods and techniques in additive manufacturing. This review critically evaluates the current 4D printing technologies, including the development and optimization of printing methods as well as to the printed objects. Previous developments in this area and contributions to the modern trend in manufacturing technology are briefly summarized. The review is divided into three sections. Firstly, the existing printing methods along with the frequently used printing materials as well as the processing parameters, and the factors which influence the quality and mechanical performances of the printed objects are discussed. Secondly, the optimization techniques, such as topology, shape, structure, and mechanical property, are described. Thirdly, the latest development and applications of additive manufacturing are depicted, and suggestions concerning the scope of future research are put forward. [ABSTRACT FROM AUTHOR]

"Knowledge is power" and distribution of knowledge is fueled by printing and photocopying industry. Even as printing and photocopying industry have revolutionized the availability of documents and perceptible image quickly at extremely inexpensive and affordable cost, the boon of its revolution has turned into a bane by irresponsible, uncontrolled and extensive use, causing irreversible degradation to not only ecosystem by continuous release of ozone and other volatile organic compounds (VOCs) but also the health of workers occupationally exposed to it. Indoor ozone level due to emission from different photocopying equipment's increases drastically and the condition of other air quality parameters are not different. This situation is particularly sedate in extremely sensitive educational and research industry where sharing of knowledge is extremely important to meet the demands. This work is an attempt to catalogue all the environmental as well as health impacts of printing or photocopying. It has been observed that printing/photocopying operation is a significant factor contributing to indoor air quality degradation, which includes increase in concentration of ozone, VOCs, semi-volatile organic compounds (SVOCs) and heavy metals such as cadmium, selenium, arsenic, zinc, nickel, and other pollutants from photocopy machines. The outcome of this study will empower the manufactures with information regarding ozone and other significant emission, so that their impact can be reduced. [ABSTRACT FROM AUTHOR]

Rapid free-form printing of particle-functionalized materials is an integral component of 3D printing and additive manufacturing. Such processes consist of attaching a dispenser to a robot arm which then releases droplets of specialized mixtures in free-space that are deposited onto a substrate. These approaches are popular because they utilize widely-available, highly-programmable, robots. However, often the release of a complex mixture in free-space is somewhat imprecise, thus electrodynamic field control has been proposed as a possible remedy to enhance the precision of such processes. Specifically, electrodynamic control of the material is achieved by electrifying the released material in the presence of a prescribed ambient electrical field generated from the substrate, in order to guide it to the desired position. There are many components that comprise such a system, thus motivating the construction of a simulation tool framework assembling submodels of the: kinematics of the robot arm and the dispenser-printer head, electrodynamic and gravitational forces on the released material, dynamics of the released material and conductive, convective and radiative cooling of the media. The modular system structure allows for easy replacement of submodels within the overall framework. Numerical simulations are undertaken to illustrate the overall system model, which is comprised of an assembly of submodels. Afterwards, a Machine Learning Algorithm (MLA) is developed to identify and optimize the proper system parameters which deliver a desired printed pattern. Specifically, an MLA is developed to ascertain the appropriate combination of robotic motion and electrical fields needed to create structures which would be difficult or impossible by purely mechanical means alone. Afterwards, extensions involving more detailed models are then provided, based on the Discrete Element Method. [ABSTRACT FROM AUTHOR]