Experimental Validation of High Precision Web Handling for a Two-Actuator-Based Roll-to-Roll System.

In this paper, experimental validation of high precision web handling for a two-actuator-based roll-to-roll (R2R) system is presented. To achieve this, the tension control loop is utilized to regulate the tension in the unwinder module, and the velocity loop is utilized to regulate the web speed in the rewinder module owing to the limitation of the number of actuators. Moreover, the radius estimation algorithm is applied to achieve an accurate web speed and the control sequence of the web handling in the longitudinal axis is developed to manipulate the web handling for convenience. Having these, the tension control performances are validated within ±0.79, ±1.32 and ±1.58 percent tension tracking error and 1.6, 1.53 and 1.33 percent web speed error at the speeds of 0.1 m/s, 0.2 m/s, and 0.3 m/s, respectively. The tension control performance is verified within ±0.3 N tracking error in the changes of the reference tension profile at 0.1 m/s web speed. Lastly, the air floating roller is used to minimize the friction terms and the inertia of the idle roller in the tension zone so that tension control performance can be better achieved during web transportation.

Force uniformity control for large-area roll-to-roll process.

Demand for high throughput manufacturing has recently increased in various fields, such as electronics, photonics, optical devices, and energy. Moreover, flexible electronic devices are indispensable in applications such as touch screens, transparent conductive electrodes, transparent film heaters, organic photovoltaics, organic light-emitting diodes, and battery. For these applications, a large-area roll-to-roll (R2R) process is a promising method for producing with high throughput. However, bending deformation of rollers is unavoidable in a large-scale R2R system, which produces non-uniformity in force distribution during processing and reduces the sample quality. In this study, we propose a new R2R imprinting module to mitigate the deformation by using an additional backup roller to achieve uniform force distribution. From numerical simulations, we found that there exists an optimal imprinting force for each backup roller length to obtain the best uniformity. Experimental results using a large-area pressure sensor verified the effectiveness of the proposed method. Finally, the R2R nanoimprint lithography process showed that the proposed method produces patterns of 100 nm width with uniform residual layer thickness, which are distributed across the substrate of 1.2 m width.

Effect of thoracic and pelvic anteroposterior diameters on spinal sagittal alignment.

PURPOSE: This study aimed to analyze the effect of the thoracic anteroposterior diameter (TAPD) and pelvic anteroposterior diameter (PAPD) on global sagittal alignment in asymptomatic patients with normal sagittal alignment. PATIENT SAMPLE: The study investigated 2042 adult patients who initially presented at our hospital with a hip and knee problem without history of symptoms related to the entire spine. Only 57 patients with normal global sagittal alignment (C2-7 sagittal vertical axis (SVA) and C7-S1 SVA of <10 mm) were considered. METHODS: The whole-spine standing lateral radiographs were obtained to analyze the following parameters: pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), thoracic inlet angle (TIA), T1 slope, cervical spinal parameters (angle of C0-2, C2-7, and C0-7), TAPD, and PAPD. Statistical analysis was performed using Pearson correlation coefficients and multiple regression analyses. RESULTS: All the parameters showed a normal distribution. TAPD had a significant relationship with thoracic kyphosis (TK; r = 0.458), TIA (r = 0.677), and C0-2 angle (r = 0.294) but no significant relationship with T1 slope and other cervical parameters. PAPD had a significant relationship with PI (r = 0.309) and PT (r = 0.463) but no significant relationship with LL, SS, and TK. The multiple regression analysis showed that TIA = 21.974 + 0.405 (TK) + 0.188 (TAPD) (p < 0.0001). CONCLUSIONS: TAPD and PAPD are associated with TIA, TK, C0-2 angle, PI, and PT, all of which act as key factors in spinal sagittal alignment. Although they did not directly correlate with other cervical parameters, T1 slope, and LL, TAPD and PAPD might have indirect effects on cervical and lumbar spinal sagittal alignment through their relationships with TIA, TK, and PI.

The Effect of a CAD/CAM-Guided Template on Formation of the Screw-Access Channel for Fixed Prostheses Supported by Lingually Placed Implants.

PURPOSE: The aim of this study was to evaluate the effect of a computer-aided design/computer-assisted manufacturing (CAD/CAM) guide on drilling the screw-access channel for lingually placed implants. MATERIALS AND METHODS: Screw-channel drilling guides were fabricated on lingually placed implant models using CAD/CAM technology. The screw channels were prepared with guided or freehand drilling by 20 dental graduates. The accuracy of each screw channel was assessed for drilling entry point, channel volume, and angulation (α = .05). RESULTS: The guided drilling group showed smaller deviations than the freehand drilling group, and prosthesis position influenced the guide effect (P < .001). CONCLUSION: The CAD/CAM guide facilitated the screw channel preparation of cement-retained prostheses supported by lingually placed implants.

Non-Radiological Method for Fabrication of a Screw-Channel Drilling Guide in Cement-Retained Implant Restorations Using Intraoral Digital Scanning and Imaging Superimposition: A Clinical Report.

The difficulty of retrieving the abutment screw is a major disadvantage of cement-retained implant restorations. Conventional methods for locating the screw-access hole are based largely on radiography or manual labor, which limits accuracy and clinical feasibility. This clinical report describes a non-radiological method for fabricating an accurate drilling guide for location of the screw channel using intraoral optical scanning, 3D superimposition, and computer-aided design and computer-aided manufacturing (CAD/CAM) technologies. The present technique not only improves the guide fabrication process and the accuracy of screw-channel drilling, but also has wide indications for implant restorations.

Double-Step Image Superimposition Technique for Fabricating a Drilling Guide to Access the Abutment Screw in Implant Prostheses.

Limited retrievability is a major disadvantage of cement-retained implant restorations. Despite great progress in locating the abutment screw within crowns, the existing techniques are based on prior data or prefabricated devices and require significant work. This study introduces a new procedure for fabricating a guide template to drill a screw access hole using a double-step superimposition technique that incorporates intraoral optical scanning, cone beam computed tomography, and dental design software. The double-step superimposition technique with computer-aided design/computer-assisted manufacturing technology can enhance the convenience and accuracy of drilling the screw-access hole.

Covalent Self-Assembly and One-Step Photocrosslinking of Tyrosine-Rich Oligopeptides to Form Diverse Nanostructures.

We present covalently self-assembled peptide hollow nanocapsule and peptide lamella. These biomimetic dityrosine peptide nanostructures are synthesized by one-step photopolymerization of a tyrosine-rich short peptide without the aid of a template. This simple approach offers direct synthesis of fluorescent peptide nanocages and free-standing thin films. The simple crosslinked peptide lamella films provide robust mechanical properties with an elastic modulus of approximately 30 GPa and a hardness of 740 MPa. These nanostructures also allow for the design of peptidosomes. The approach taken here represents a rare example of covalent self-assembly of short peptides into nano-objects, which may be useful as microcompartments and separation membranes.

Controllable pneumatic generator based on the catalytic decomposition of hydrogen peroxide.

This paper presents a novel compact and controllable pneumatic generator that uses hydrogen peroxide decomposition. A fuel micro-injector using a piston-pump mechanism is devised and tested to control the chemical decomposition rate. By controlling the injection rate, the feedback controller maintains the pressure of the gas reservoir at a desired pressure level. Thermodynamic analysis and experiments are performed to demonstrate the feasibility of the proposed pneumatic generator. Using a prototype of the pneumatic generator, it takes 6 s to reach 3.5 bars with a reservoir volume of 200 ml at the room temperature, which is sufficiently rapid and effective to maintain the repetitive lifting of a 1 kg mass.

Synthesis, bioevaluation and docking study of 5-substitutedphenyl-1,3,4-thiadiazole-based hydroxamic acids as histone deacetylase inhibitors and antitumor agents.

Since the first histone deacetylase (HDAC) inhibitor (Zolinza®, widely known as suberoylanilide hydroxamic acid; SAHA) was approved by the Food and Drug Administration for the treatment of T-cell lymphoma in 2006, the search for newer HDAC inhibitors has attracted a great deal of interest of medicinal chemists worldwide. As a continuity of our ongoing research in this area, we designed and synthesized a series of 5-substitutedphenyl-1,3,4-thiadiazole-based hydroxamic acids as analogues of SAHA and evaluated their biological activities. A number of compounds in this series, for example, N(1)-hydroxy-N(8)-(5-(2-chlorophenyl)-1,3,4-thiadiazol-2-yl)octandiamide (5b), N(1)-hydroxy-N(8)-(5-(3-chlorophenyl-1,3,4-thiadiazol-2-yl)octandiamide (5c) and N(1)-hydroxy-N(8)-(5-(4-chlorophenyl)-1,3,4-thiadiazol-2-yl)octandiamide (5d), were found to possess potent anticancer cytotoxicity and HDAC inhibition effects. Compounds 5b-d were generally two- to five-fold more potent in terms of cytotoxicity compared to SAHA against five cancer cell lines tested. Docking studies revealed that these hydroxamic acid displayed higher affinities than SAHA toward HDAC8.

Preoperative three-dimensional CT angiography to distinguish between an aberrant subclavian artery and a double aortic arch in thyroid surgery: Report of 2 cases.

A non-recurrent inferior laryngeal nerve (NRILN), a very rare anatomic variation, is easily damaged during thyroid surgery. Due to impairments during embryonic development, a NRILN is frequently associated with an aberrant subclavian artery. Thus, an aberrant subclavian artery is now regarded as an important vascular anomaly for predicting the presence of a NRILN using various imaging modalities. However, precise imaging is often necessary as other vascular anomalies, such as a double aortic arch, can cause difficulties in discriminating between an aberrant subclavian artery and other anatomic variations. For this reason, computed tomography (CT) is usually necessary before thyroid surgery. but, to take more precise images, newly developed techniques such as computed tomography angiography (CTA) are needed. To indentify NRILNs, we performed CTA preoperatively in two patients with thyroid cancer. CTA demonstrated an aberrant subclavian artery with an associated NRILN in one patient and a double aortic arch with a recurrent inferior laryngeal nerve (RILN) in the second patient. Thyroid surgery was successful, and the laryngeal nerve was preserved in both patients. Preoperative CTA is much safer and less time-consuming than catheter angiography. Also, CTA is a cost-effective three-dimensional imaging modality for identifying aberrant subclavian arteries associated with NRILNs, as compared with double aortic arches associated with RILNs.

A case of right atrial aneurysm incidentally found in old age.

Right atrial aneurysm is a rare abnormality of unknown origin. Approximately half of patients with right atrial aneurysm show no symptoms. Right atrial aneurysm is usually detected by chance at any time between fetal and adult life and can be associated with atrial arrhythmia and systemic embolism. The diagnosis of right atrial aneurysm can be established with echocardiography, computed tomography (CT) or magnetic resonance imaging (MRI). Because of thromboembolic risk, aneurysmectomy is usually recommended. We review the case report of a 69-year-wold woman with right atrial appendiceal aneurysm, whose diagnosis was established by echocardiography and CT angiography.

All-fiber spot-size transformer for efficient free-space optical interconnecting devices.

A new concatenated configuration of optical fibers is proposed to improve misalignment tolerance and working distance in a free-space optical interconnection. The structure is composed of three segments: a thermally expanded core fiber, a coreless silica fiber, and a claddingless graded-index fiber. A numerical analysis for the design of each fiber segment is performed completely, and the device characteristics are experimentally evaluated in terms of the tolerances for a 1-dB coupling-loss increment against longitudinal, transverse, and angular misalignments.