Effect of different a-InGaZnO TFTs channel thickness upon self-heating stress

In this work, Indium-Galium-Zinc-Oxide Thin Film Transistors (IGZO TFTs) with different channel thickness has been compared after self-heating stress (SHS). In previous literatures, self-heating of TFTs has been widely discussed and Joule Heat caused during driving TFTs has been compared with different channel length and width [1]. However, different channel thickness hasn’t been investigated. Although TFTs with a larger channel thickness possess a greater drain current, a less degradation is observed when comparing with small channel thickness structures, demonstrated in Figure 1(a). The ΔVt shift in the transfer characteristics are well described by the stretched-exponential equation. The Eτ value, which is the average effective barrier height for electron transport, is extracted in Figure (b). Results has shown that in the thick IGZO TFTs, the value is almost twice of that in the thin IGZO TFTs. From COMSOL simulations demonstrated in Figure 1(c), in could be noticed that different channel thickness effects the electrical field locating at the gate insulator. Therefore, a model is proposed to explain the degradation difference, illustrated in Figure (4). Please click Additional Files below to see the full abstract

Lightly Weighted Automatic Audio Parameter Extraction for the Quality Assessment of Consensus Auditory-Perceptual Evaluation of Voice

The Consensus Auditory-Perceptual Evaluation of Voice is a widely employed tool in clinical voice quality assessment that is significant for streaming communication among clinical professionals and benchmarking for the determination of further treatment. Currently, because the assessment relies on experienced clinicians, it tends to be inconsistent, and thus, difficult to standardize. To address this problem, we propose to leverage lightly weighted automatic audio parameter extraction, to increase the clinical relevance, reduce the complexity, and enhance the interpretability of voice quality assessment. The proposed method utilizes age, sex, and five audio parameters: jitter, absolute jitter, shimmer, harmonic-to-noise ratio (HNR), and zero crossing. A classical machine learning approach is employed. The result reveals that our approach performs similar to state-of-the-art (SOTA) methods, and outperforms the latent representation obtained by using popular audio pre-trained models. This approach provide insights into the feasibility of different feature extraction approaches for voice evaluation. Audio parameters such as jitter and the HNR are proven to be suitable for characterizing voice quality attributes, such as roughness and strain. Conversely, pre-trained models exhibit limitations in effectively addressing noise-related scorings. This study contributes toward more comprehensive and precise voice quality evaluations, achieved by a comprehensively exploring diverse assessment methodologies.Comment: Published in IEEE 42th International Conference on Consumer Electronics (ICCE 2024

Reliability of flexible low temperature poly-silicon thin film transistor

This work reports the effect of mechanical stress-induced degradation in flexible low-temperature polycrystalline-silicon thin-film transistors. After 100,000 iterations of channel-width-direction mechanical compression at R=2mm, a significant shift of extracted threshold voltage and an abnormal hump at the subthreshold region were found. Simulation reveals that both the strongest mechanical stress and electrical field takes place at both sides of the channel edge, between the polycrystalline silicon and gate insulator. The gate insulator suffered from a serious mechanical stress and result in a defect generation in the gate insulator. The degradation of the threshold voltage shift and the abnormal hump can be ascribed to the electron trapping in these defects. In addition, this work introduced three methods to reduce the degradation cause by the mechanical stress, including the quality improvement of the gate insulator, organic trench structure and active layer with a wing structure. Please click Additional Files below to see the full abstract

Antibacterial Activity and Biocompatibility of a Chitosan-Gamma-Poly( Glutamic Acid) Polyelectrolyte Complex Hydrogel

In this study, we prepared a polyelectrolyte complex (PEC) hydrogel comprising chitosan as the cationic polyelectrolyte and gamma-poly( glutamic acid) (gamma-PGA) as the anionic polyelectrolyte. Fourier transform infrared spectroscopy revealed that ionic complex interactions existed in the chitosan-gamma-PGA PEC hydrogels. The compressive modulus increased upon increasing the degree of complex formation in the chitosan- gamma-PGA PEC hydrogel; the water uptake decreased upon increasing the degree of complex formation. At the same degree of complex formation, the compressive modulus was larger for the chitosan-dominated PEC hydrogels; the water uptake was larger for the gamma-PGA-dominated ones. Scanning electron microscopy images revealed the existence of interconnected porous structures (pore size: 30 -100 mu m) in all of the chitosan-gamma-PGA PEC hydrogels. The chitosan-gamma-PGA PEC hydrogels also exhibited antibacterial activity against Escherichia coli and Staphylococcus aureus. In addition, in vitro cell culturing of 3T3 fibroblasts revealed that all the chitosan-gamma-PGA PEC hydrogels were effective in promoting cell proliferation , especially the positively charged ones (chitosan-dominated ). Therefore, the chitosan-gamma-PGA polyelectrolyte hydrogel appears to have potential as a new material for biomedical applications

Developments of Chitosan as Functional Biomaterials

幾丁質(Chitin)是自然界中數量僅次纖維素的多醣類，大多存在海洋生物幾以及陸地昆蟲的外殼之中，也有部分存在真菌類的細胞壁之內。幾丁聚醣(Chitosan)是由幾丁質經過去乙醯化而得到，具有生物可分解性、生物相容性及抗菌性。幾丁聚醣經過適度加工與改質後，其應用更為廣泛，目前常被用在骨組織再造、藥物釋放、創傷敷料等應用。本研究致力於開發幾丁聚醣成為更具有應用性的生醫材料。 第一章為文獻回顧，唯有了解過去的研究以及未來的發展，才能鑑古知今並且繼往開來。 在第二章，我們以醋酸切割製備各種不同分子的的幾丁聚醣，並更劑音部對這個酸解的過程作動力學分析。除了得到不同分子量的幾丁聚醣以外，我們也對其化學結構進行鑑定，更研究了小分子量幾丁聚醣對於紅血球聚集的影響。最後提出酸解過程的反應機制。 第三章，幾丁聚醣與聚麩胺酸屆者簡單的靜電作用力，而形成穩定的聚電解質。我們根據理論劑算設計不同組成比例的聚電解質，除了有物理化學性值得討論之外，更對其抗菌的特性有深入的刻化。 第四張為第三章的延伸，開發幾丁聚醣與聚麩胺酸聚電解質為創傷敷料。 第五章則是延續三、四兩章，研究生物軟組織(上皮組織與肌肉組織)幾丁聚醣與聚麩胺酸聚電解質的生物反應。 第六章則是開發幾丁聚醣與琥珀酸成為透明的生物水膠，這樣全天然可裂解的生物水膠具有取代壓克力水膠的潛力。Chitin, next to cellulose, is the second most abundant polysaccharide in nature; it is widely found in the exoskeletons of crustacea and insects as well as in the cell walls of fungi and algae. Prepared by the N-deacetylation of chitin, chitosan is a semi-crystalline polysaccharide constituted by N-glucosamine and N-acetyl-glucosamine units, with an amount of N-glucosamine units exceeding 50%. Since chitosan is reported to have many promising properties, the aim of this thesis is to develop and magnify chitosan as practical biomaterial. The first chapter reviewed researches done before; it is necessary to understand and have a full scope in the past and the trend of future. In the second chapter, the preparation of chitosan of different molecular weight with acetic acid and the kinetics of acid-depolymerization were discussed. The structure identification of these depolymerized chitosan is performed and its preliminary blood compatibility was also investigated. Finally, the acid-depolymerization mechanism of chitosan is proposed. In the third chapter, chitosan/γ-Poly(glutamic acid) PEC hydrogel, formed by ionic interactions, were fabricated based on several compositions by varying molar ratios of amine groups of chitosan to carboxylic acid groups of γ-PGA. Beside the physicochemical characteristics of these chitosan/γ-PGA PEC hydrogels, their physical behaviors and in vitro biological behaviors were also fully investigated. In the fourth chapter, based on the previous chapter, the in vivo evaluation was conducted to develop chitosan/γ-PGA PECs as wound dressing materials. The fifth chapter was designed to assess the in vivo epithelium tissue and muscle tissue response of chitosan/γ-PGA PECs using a rat model. We have examined several factors affecting the soft tissue response. The sixth chapter was dedicated to develop the superabsorbent hydrogel as a good mimic for extracellular matrix. The hydrogel was composed of all nature poymer, fabricated by the amide bond formation, hoping to be a replacement of acrylate-based hydrogel

PEG-Chitosan Hydrogel with Tunable Stiffness for Study of Drug Response of Breast Cancer Cells

Mechanical properties of the extracellular matrix have a profound effect on the behavior of anchorage-dependent cells. However, the mechanisms that define the effects of matrix stiffness on cell behavior remains unclear. Therefore, the development and fabrication of synthetic matrices with well-defined stiffness is invaluable for studying the interactions of cells with their biophysical microenvironment in vitro. We demonstrate a methoxypolyethylene glycol (mPEG)-modified chitosan hydrogel network where hydrogel stiffness can be easily modulated under physiological conditions by adjusting the degree of mPEG grafting onto chitosan (PEGylation). We show that the storage modulus of the hydrogel increases as PEGylation decreases and the gels exhibit instant self-recovery after deformation. Breast cancer cells cultured on the stiffest hydrogels adopt a more malignant phenotype with increased resistance to doxorubicin as compared with cells cultured on tissue culture polystyrene or Matrigel. This work demonstrates the utility of mPEG-modified chitosan hydrogel, with tunable mechanical properties, as an improved replacement of conventional culture system for in vitro characterization of breast cancer cell phenotype and evaluation of cancer therapies

Urinalysis Using a Diaper-Based Testing Device

Urinary tract infections (UTI), one of the most common bacterial infections, annually affect 150 million people worldwide. Infants and the elderly are likely to have missed or delayed diagnosis of UTI due to difficulty clearly describing their symptoms. A rapid screening method for UTI is a critical and urgent need for these populations. The aim of our study is to develop a diaper-based testing device to assay urine biomarkers including pH, leukocyte, and nitrite level. This all-in-one device assists in urine collection and testing using a colorimetric approach to provide easily read visual results on the outside surface of a test strip-integrated diaper. In this study, we tested samples from 46 patients using testing strips and examined the results from 7 patients recruited to validate the strip-integrated diaper. In conclusion, this new diaper-based testing device is easy to use, rapid, and inexpensive, all of which imbue it with tremendous potential for development into a commercially viable UTI screening system

Glycogen synthase kinase-3 ss is critical for Interferon-a-induced serotonin uptake in human Jurkat T cells

Dysregulation of glycogen synthase kinase (GSK)-3 beta contributes to the pathophysiology of mood disorders. However, how its regulation is responsible for the functioning of serotonin (5-HT) requires further investigation. Although enhancement of T-cell function may present an alternative strategy to treat depression, the precise mechanisms have yet to be established. Our previous studies have found that interferon-alpha (IFN-a) up-regulates serotonin transporter (5-HTT) expression and induces 5-HT uptake in T cells. The present study is to examine GSK-3 beta regulation on IFN-a-induced 5-HTT functions. GSK-3 beta short hairpin RNAs (shRNAs) or GSK-3 beta inhibitors decreased IFN-a-induced 5-HT uptake and 5-HTT expression. Src activation and calcium/calcium-activated calmodulin kinase II (CaMKII) were involved in IFN-a-induced phosphorylation of proline-rich tyrosine kinase 2 (Pyk2) (Tyr402) and GSK-3 beta (Tyr216), which regulated 5-HT uptake. GSK-3 beta knockdown blocked the IFN-a-induced phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 (Thr202/Tyr204) and signal transducer and transactivator (STAT) 1. In addition to inhibiting ERK, a selective 5-HTT inhibitor fluoxetine blocked IFN-a-induced activations of Src, CaMKII-regulated Pyk2/GSK-3 beta cascade, as well as STAT1 activation and translocation. These results indicated that calcium/CaMKII- and Src-regulated Pyk2 participated in IFN-a-induced GSK-3 beta activation and GSK-3 beta-regulated 5-HT uptake. GSK-3 beta signaling facilitated IFN-a-activated STAT1 by regulating ERK1/2, which controlled 5-HT uptake. Fluoxetine interfered with the Pyk2/GSK-3 beta cascade, thereby inhibiting IFN-a-induced 5-HT uptake. J. Cell. Physiol. 227: 25562566, 2012. (c) 2011 Wiley Periodicals, Inc