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In this study, the antiferroelectric (AFE) and electrocaloric (EC) characteristics of lead-free titanium (Ti)-doped zirconia (ZrO2) thin films deposited via high-power impulse magnetron sputtering (HiPIMS) were investigated. The argon-to-oxygen ratio was initially optimized during deposition to obtain a more stoichiometric ZrO2 film for enhanced antiferroelectricity. Furthermore, enhanced crystallinity was achieved through the incorporation of Ti atoms into ZrO2 thin films as confirmed via grazing incidence X-ray diffraction and high-resolution transmission electron microscopy. For metal-insulator-metal capacitors with Ti-doped ZrO2 thin films, the AFE behaviors were significantly improved because of the excellent crystallinity of the tetragonal phase. Based on a fast polarization response and robust fatigue resistance under a 106-cycle endurance test, the EC effect was successfully explored, and an adiabatic temperature change (ΔT) of −14.8 K was realized. With competitive EC properties, Ti-doped ZrO2 thin films deposited via HiPIMS are proposed as promising candidates for use in future cooling systems.

Concern of city breathability has increased in recent project planning activities. Most previous studies in the literature have demonstrated that it is possible to improve urban ventilation efficiency by manipulating the arrangement of buildings with the integration of half open spaces into building configurations. In considering the arcade design which is a conventional type of half open space, this paper first focuses on examining the ventilation performance in a realistic high-rise urban area and its associated city breathability in terms of the ACH* (defined as the ratio of the ACH to a characteristic frequency, determined by the reference velocity of the far upstream free flow divided by the reference building height) with or without incorporating an arcade into the object buildings. On-site measurements are conducted to validate the computational model. Then, the optimization procedures are presented, in which correlations from multivariable regression from our earlier study on generic urban street canyons are applied as the design guidelines for the arcade to maximize the ACH*. Computational fluid dynamics simulations are extended to take into consideration buildings with an arcade of optimum height and width in actual urban canyons to determine the effectiveness of the optimization procedures used to design arcade buildings for enhancing city breathability.

Vascular endothelial growth factor (VEGF) plays a pivotal role in angiogenesis. Previous studies focused on transcriptional regulation modulated by proximal upstream cis-regulatory elements (CREs) of the human vegfa promoter. However, we hypothesized that distal upstream CREs may also be involved in controlling vegfa transcription. In this study, we found that the catalytic domain of Seryl-tRNA synthetase (SerRS) interacted with transcription factor Yin Yang 1 (YY1) to form a SerRS/YY1 complex that negatively controls vegfa promoter activity through binding distal CREs at −4654 to −4623 of vegfa. Particularly, we demonstrated that the −4654 to −4623 segment, which predominantly controls vegfa promoter activity, is involved in competitive binding between SerRS/YY1 complex and NFKB1. We further showed that VEGFA protein and blood vessel development were reduced by overexpression of either SerRS or YY1, but enhanced by the knockdown of either SerRS or yy1. In contrast, these same parameters were enhanced by overexpression of NFKB1, but reduced by knockdown of nfkb1. Therefore, we suggested that SerRS does not bind DNA directly but form a SerRS/YY1 complex, which functions as a negative effector to regulate vegfa transcription through binding at the distal CREs; while NFKB1 serves as a positive effector through competing with SerRS/YY1 binding at the overlapping CREs.

Background: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract. GISTs often occur in middle-aged and older individuals. The main morphologic type of GISTs is the spindle cell type. Immunohistochemistry and genotyping can help to identify GISTs from other subgroups of sarcoma. Materials and Methods: This retrospective study collected 304 patients over a 10-year period (from January 2009 to June 2019) who were diagnosed with GISTs based on the pathological database of our hospital. We retrospectively analyzed the clinical manifestations and treatment strategies. Results: Anemia or gastrointestinal bleeding was the most common symptom (36.5%), followed by gastrointestinal discomfort (32.6%) and incidental findings (21.4%). Ruptured tumors with hollow organ perforation increased the mortality risk. Liver metastasis and peritoneal seeding were the most two common patterns of recurrence. GISTs arising in adults are characterized by the near-universal expression of CD117/KIT antigen. Early surgery with margin-free resection is the best strategy for GISTs without metastasis. Routine lymph node dissection is not recommended. Laparoscopic surgery is feasible and safe for GISTs in the gastrointestinal tract. Endoscopic submucosal dissection to treat GISTs is suitable for small tumors with very low-to-intermediate risk in the stomach. Postoperative treatment with tyrosine kinase inhibitors can prolong recurrence-free survival after surgery. Conclusion: Surgical resection is the preferred treatment for patients without metastasis. Administration of tyrosine kinase inhibitors such as imatinib is recommended for unresectable, metastatic, or recurrent GISTs. Postoperative follow-up by computed tomography to detect early recurrence is recommended.

In this paper, a self-constructing fuzzy wavelet neural network (SFWNN) is used to approximate an unknown nonlinear term in the system dynamics with the structure and parameter learning abilities concurrently. Further, a self-constructing fuzzy wavelet neural control (SFWNC) system, which is composed of a computation controller and a robust compensator, is proposed. The computation controller using the SFWNN approximator is the main controller and the robust compensator is designed to eliminate the effect of the approximation error. All controller parameters of the SFWNC system are adaptively update based on the Lyapunov stability theory and the projection algorithm to guarantee the closed-loop system stability. Finally, the effectiveness of the proposed SFWNC system is verified by simulation results and the SFWNN approximator has the admirable property of small fuzzy rules size and high learning accuracy.

A hollow polymer microneedle array with tips and lumens that mimic conventional hypodermic needles, fabricated using UV lithography, and a single-step micromolding technique, is presented for drug delivery into skin. This 6 × 6 needle array consists of 1-mm tall high-aspect ratio hollow microneedles with sharp beveled tips and 150-μm diameter side-opened lumens. A 2-D lithographic mask pattern and the topography of the micromold are utilized simultaneously to define the geometry of the beveled tip and the position of the lumen. Mechanical insertion and fluidic injection characterization of these hypodermic-needle-like (HNL) microneedles (MNs) were performed using excised porcine skin as a substrate. The required insertion force of an HNL MN is 0.275 N, which is comparable with that of a 26-gauge hypodermic needle, 0.284 N. These results are an order of magnitude reduction in insertion force over pyramidal-tip MNs of comparable diameter previously reported by us. This insertion force reduction confirms that the tip geometry is an important factor in utilization of MNs in these applications. No needle fracture was observed under an optical microscope following the pressing of an HNL MN against excised porcine skin with application force of 50 N. Preliminary manual injection of dye through an HNL MN from a syringe into excised porcine skin verified the injection functionality of HNL MNs. [2013-0219].

This study investigated the sensor performance and durability of flexible graphene-based micro-capacitor using ultrafast laser ablation with picosecond (PS) pulses. Micro-patterns were fabricated under varying electrode widths, lengths, and gaps on the flexible polyethylene terephthalate (PET) substrates for optimal capacitive performance. The experimental results showed that the untouched capacitance of the micro-capacitors had an approximately linear relationship with electrode widths and lengths. Increasing the electrode width can effectively enhance capacitance of the micro-capacitor, especially under small electrode gap. Micro-capacitors exhibited stable relative resistance change and excellent capacitance retention when bending angle θ ≤ 30° after 1000 times bending test. The decreasing rates of capacitance retention substantially increased with bending angles from 30° to 180°. Touched capacitances increased sharply as pressure rose from 0 to 6 kPa. These experimental results can be considered in designs of durable and high sensitivity flexible graphene-based touch sensors.

The human larynx is an important organ for voice production and respiratory mechanisms. The vocal cord is approximated for voice production and open for breathing. The videolaryngoscope is widely used for vocal cord examination. At present, physicians usually diagnose vocal cord diseases by manually selecting the image of the vocal cord opening to the largest extent (abduction), thus maximally exposing the vocal cord lesion. On the other hand, the severity of diseases such as vocal palsy, atrophic vocal cord is largely dependent on the vocal cord closing to the smallest extent (adduction). Therefore, diseases can be assessed by the image of the vocal cord opening to the largest extent, and the seriousness of breathy voice is closely correlated to the gap between vocal cords when closing to the smallest extent. The aim of the study was to design an automatic vocal cord image selection system to improve the conventional selection process by physicians and enhance diagnosis efficiency. Also, due to the unwanted fuzzy images resulting from examination process caused by human factors as well as the non-vocal cord images, texture analysis is added in this study to measure image entropy to establish a screening and elimination system to effectively enhance the accuracy of selecting the image of the vocal cord closing to the smallest extent.

This study used the actual laryngeal video stroboscope videos taken by physicians in clinical practice as the samples for experimental analysis. The samples were dynamic vocal fold videos. Image processing technology was used to automatically capture the image of the largest glottal area from the video to obtain the physiological data of the vocal folds. In this study, an automatic vocal fold disease identification system was designed, which can obtain the physiological parameters for normal vocal folds, vocal paralysis and vocal nodules from image processing according to the pathological features. The decision tree algorithm was used as the classifier of the vocal fold diseases. The identification rate was 92.6%, and the identification rate with an image recognition improvement processing procedure after classification can be improved to 98.7%. Hence, the proposed system has value in clinical practices.

Drug delivery through micromachined needles is an attractive alternative to intramuscular and subdermal injection by hypodermic needles, due to the potential for reduced pain caused by the micro-sized needles. In this paper, a polymer-based fabrication process using UV lithography into micromolds is developed, allowing the fabrication of microneedle (MN) shafts, tips, lumens, and substrate baseplate using lithography. Using UV lithography into micromolds allows complex three-dimensional structures to be defined, since both mask patterns and mold topography are available to define the structures. A hollow MN array and baseplate, in which the needle lumens extend through the thickness of the baseplate, are demonstrated. Fabricated SU-8 MNs are 825 μm in height and 400 μm in width, with a pyramidal tip; the needle lumen, 120 μm in diameter, intersects with one of the faces of the pyramidal tip. Mechanical characterization of the fabricated MNs shows that the fracture force of a single needle against a rigid surface is 12.0 N. The insertion force of a single needle into porcine skin is empirically determined to be 2.4 N. The fracture force of the needle against porcine skin is observed to be in excess of 90 N.

The layered coding structure of scalable video coding (SVC) with adaptive inter-layer prediction causes noticeable computational complexity increments when compared to existing video coding standards. To lighten the computational complexity of SVC, we present a fast algorithm to speed up the inter-mode decision process. The proposed algorithm terminates inter-mode decision early in the enhancement layers by estimating the rate-distortion (RD) cost from the macroblocks of the base layer and the enhancement layer in temporal, spatial, and inter-layer directions. Moreover, a search range decision algorithm is also proposed in this paper to further increase the motion estimation speed by using the motion vector information from temporal, spatial, or inter-layer domains. Simulation results show that the proposed algorithm can determine the best mode and provide more efficient total coding time saving with very slight RD performance degradation for spatial and quality scalabilities.

In this paper, we present an on-line learning neuro-fuzzy system which was inspired by parts of the mecha- nisms in immune systems. It illustrates how an on-line learning neuro-fuzzy system can capture the basic elements of the immune system and exhibit some of its appealing properties. During the learning procedure, a neuro-fuzzy system can be incrementally constructed. We illustrate the potential of the on-line learning neuro-fuzzy system on several benchmark classification problems and function approximation problems.

In this paper, a speaker adaptation method to adapt an existing speaking rate-dependent hierarchical prosodic model (SR-HPM) of an SR-controlled Mandarin TTS system to new speaker's data for realizing a new voice is proposed. Two main problems are addressed: data sparseness for few adaptation utterances existing only in a small range of normal speaking rate and no adaptation data in both ranges of fast and slow speaking rates. The proposed method follows the idea of SR-HPM training to firstly normalize the prosodic-acoustic features of the new speaker's speech data, to then train an HPM by the prosody labeling and modeling algorithm, and to lastly refine the HPM to an SR-dependent model. The MAP adaptation method with model parameter extrapolation is applied to cope with the above two problems. Experimental results on a male speaker's adaptation data confirmed that the resulting adaptive SR-HPM has reasonable parameters covering a wide range of speaking rates and hence can be used in the TTS system to generate prosodic-acoustic features for synthesizing the new speaker's voice of any given SR.

Palmitoyl glycol chitosan (GCP) hydrogel has been reported as erodible controlled-release systems for the delivery of both hydrophilic and hydrophobic molecules. In this study we prepared lauroyl/palmitoyl glycol chitosan (GCL/GCP) in gel form and evaluated their application for skin delivery of the hydrophilic compound, magnesium ascorbyl phosphate (MAP), which is widely used in cosmetic formulations. Release of MAP from the polymer gels was significantly decreased with increasing concentration of GCL/GCP in the formulations in comparison with glycol chitosan (GC). In both aqueous and 10% ethanol vehicles, MAP flux was increased 1.58- to 3.96-fold of 1% GC from 1% GCL/GCP. Increase in MAP flux was correlated to the increase in GCL/GCP concentration prepared in 10% ethanol vehicle. GCL/GCP, in either water or 10% ethanol vehicles, increased the skin penetration and skin deposition of MAP in comparison with GC, hydroxypropylmethylcellulose, and carbopol, while sustaining its release from the polymer gels. Both the enhancement in skin penetration/deposition and sustained release of MAP were depended on polymer concentration. Also, with increase in polymer concentration, epidermal to dermal drug deposition ratio tended to increase, which will be beneficial to its activity in the epidermis, such as inhibition of tyrosinase and protection from UV damage. These data suggested both GCL and GCP can be applied as delivery vehicles to improve percutaneous absorption of MAP.

This paper presents a polymer hollow microneedle array for transdermal drug delivery that is fabricated using UV photolithography and a single-step micromolding technique. This fabrication process patterns a 6×6 array of 1mm tall high-aspect-ratio hollow microneedles with sharp beveled tips and 150µm diameter side-opened lumens. The geometry of the beveled tip and the position of the lumen are defined simultaneously by a two-dimensional lithography mask pattern and the topography of the micromold. This three-dimensional geometry improves insertion performance and potentially the drug delivery efficiency without additional fabrication processes. These hypodermic-needle-like microneedles have been successfully constructed, packaged, and tested for fluidic functionality and skin penetrability.

This paper presents a fabrication process combining micromolding and direct drawing, and its application to the development of high aspect ratio microneedles. Without using photolithography or etching, the proposed process creates microneedles with: 1) higher aspect ratios than that of the original mold, 2) controllable needle diameter for optimized mechanical strength, and 3) arrowhead-shaped tips for potentially increased capacity and effective payload delivery. The needles presented are formed with biocompatible, water-soluble polymers, but the fabrication process inherently allows many kinds of polymers to be exploited. Various high aspect ratio 3D structures were fabricated and characterized, and the fabrication result was compared with theoretical prediction. Water-soluble microneedle arrays have been fabricated and successfully penetrated into porcine skin, fully releasing the drug-surrogate into the dermis layer within a minute.

This paper presents a dissolvable-tipped, drug-reservoir integrated microneedle array for transdermal drug delivery. The hydrogel-based dissolvable tips are formed in a reusable polydimethylsiloxane (PDMS) mold, and then contact-transferred onto a microtube array with drug-surrogate pre-filled reservoirs incorporated into each microneedle. The microtube array is fabricated by a single photolithography process using a gray-tone mask. After insertion into an agarose gel, the water-soluble tips effectively dissolve within a minute to expose each reservoir, and the pre-filled drug-surrogate successfully diffuses. A preliminary tissue penetration test shows mechanical stability of the dissolvable tipped microneedle and feasibility of drug delivery as well as safe prevention of the proposed microneedle from possible reuse.

Transdermal drug delivery through microneedles is a minimally invasive procedure causing little or no pain, and is a potentially attractive alternative to intramuscular and subdermal drug delivery methods. This paper demonstrates the fabrication of a hollow microneedle array using a polymer-based process combining UV photolithography and replica molding techniques. The key characteristic of the proposed fabrication process is to define a hollow lumen for microfluidic access via photopatterning, allowing a batch process as well as high throughput. A hollow SU-8 microneedle array, consisting of 825mum tall and 400 mum wide microneedles with 15-25 mum tip diameters and 120 mum diameter hollow lumens was designed, fabricated and characterized.

The authors examine the influence of a variety of processing variables on the specific contact resistance of Ti/Al/Pt/Au ohmic contacts to n-type AlGaN, and we study the effect of replacing Ti with V when fabricating ohmic contacts to n-type AlGaN/GaN HEMT epilayers. The replacement of Ti with V allows the annealing temperature for formation of low resistance ohmic contacts to be decreased by 150 /spl deg/C.