Channel-Composition-Dependent Characteristics of -Doped InxAl1-xAs/InyGa1-yAs Metamorphic High Electron Mobility Transistors

Ching-Sung Lee,Chia-Jeng Chian,Wei-Chou Hsu,Ke-Hua Su,Su-Jen Yu 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.4

This work provides comprehensive comparisons of the device characteristics, including the voltage gain, power performance, linearity and noise characteristics, for InAlAs/InGaAs/GaAs metamorphic high electron mobility transistors with respect to different indium contents in the InGaAs channel. Though the device with a high In-ratio InGaAs channel usually demonstrated improved high-frequency characteristics, the kink effects in their narrow-gap channel materials were found to seriously degrade the device performance. On the other hand, the low In-ratio channel device had characteristics advantageous for high-gain and high-linearity applications while the device with a compromised channel composition design was suitable for high-power circuit applications. This work provides comprehensive comparisons of the device characteristics, including the voltage gain, power performance, linearity and noise characteristics, for InAlAs/InGaAs/GaAs metamorphic high electron mobility transistors with respect to different indium contents in the InGaAs channel. Though the device with a high In-ratio InGaAs channel usually demonstrated improved high-frequency characteristics, the kink effects in their narrow-gap channel materials were found to seriously degrade the device performance. On the other hand, the low In-ratio channel device had characteristics advantageous for high-gain and high-linearity applications while the device with a compromised channel composition design was suitable for high-power circuit applications.

Microcantilever biosensor: sensing platform, surface characterization and multiscale modeling

Chen, Chuin-Shan,Kuan, Shu,Chang, Tzu-Hsuan,Chou, Chia-Ching,Chang, Shu-Wei,Huang, Long-Sun Techno-Press 2011 Smart Structures and Systems, An International Jou Vol.8 No.1

The microcantilever (MCL) sensor is one of the most promising platforms for next-generation label-free biosensing applications. It outperforms conventional label-free detection methods in terms of portability and parallelization. In this paper, an overview of recent advances in our understanding of the coupling between biomolecular interactions and MCL responses is given. A dual compact optical MCL sensing platform was built to enable biosensing experiments both in gas-phase environments and in solutions. The thermal bimorph effect was found to be an effective nanomanipulator for the MCL platform calibration. The study of the alkanethiol self-assembly monolayer (SAM) chain length effect revealed that 1-octanethiol ($C_8H_{17}SH$) induced a larger deflection than that from 1-dodecanethiol ($C_{12}H_{25}SH$) in solutions. Using the clinically relevant biomarker C-reactive protein (CRP), we revealed that the analytical sensitivity of the MCL reached a diagnostic level of $1{\sim}500{\mu}g/ml$ within a 7% coefficient of variation. Using grazing incident x-ray diffractometer (GIXRD) analysis, we found that the gold surface was dominated by the (111) crystalline plane. Moreover, using X-ray photoelectron spectroscopy (XPS) analysis, we confirmed that the Au-S covalent bonds occurred in SAM adsorption whereas CRP molecular bindings occurred in protein analysis. First principles density functional theory (DFT) simulations were also used to examine biomolecular adsorption mechanisms. Multiscale modeling was then developed to connect the interactions at the molecular level with the MCL mechanical response. The alkanethiol SAM chain length effect in air was successfully predicted using the multiscale scheme.

Microcantilever biosensor: sensing platform, surface characterization and multiscale modeling

Chuin-Shan Chen,Shu Kuan,Tzu-Hsuan Chang,Chia-Ching Chou,Shu-Wei Chang,Long-Sun Huang 국제구조공학회 2011 Smart Structures and Systems, An International Jou Vol.8 No.1

The microcantilever (MCL) sensor is one of the most promising platforms for next-generation label-free biosensing applications. It outperforms conventional label-free detection methods in terms of portability and parallelization. In this paper, an overview of recent advances in our understanding of the coupling between biomolecular interactions and MCL responses is given. A dual compact optical MCL sensing platform was built to enable biosensing experiments both in gas-phase environments and in solutions. The thermal bimorph effect was found to be an effective nanomanipulator for the MCL platform calibration. The study of the alkanethiol self-assembly monolayer (SAM) chain length effect revealed that 1-octanethiol (C8H17SH) induced a larger deflection than that from 1-dodecanethiol (C12H25SH) in solutions. Using the clinically relevant biomarker Creactive protein (CRP), we revealed that the analytical sensitivity of the MCL reached a diagnostic level of 1~500 μg/ml within a 7% coefficient of variation. Using grazing incident x-ray diffractometer (GIXRD) analysis, we found that the gold surface was dominated by the (111) crystalline plane. Moreover, using X-ray photoelectron spectroscopy (XPS) analysis, we confirmed that the Au-S covalent bonds occurred in SAM adsorption whereas CRP molecular bindings occurred in protein analysis. First principles density functional theory (DFT) simulations were also used to examine biomolecular adsorption mechanisms. Multiscale modeling was then developed to connect the interactions at the molecular level with the MCL mechanical response. The alkanethiol SAM chain length effect in air was successfully predicted using the multiscale scheme.

Cardiovascular Medication Use and Risk of Acute Exacerbation in Patients With Asthma-COPD Overlap (CVACO Study)

Su Vincent Yi-Fong,Ko Szu-Wen,Chang Yuh-Lih,Chou Yueh-Ching,Lee Hsin-Chen,Yang Kuang-Yao,Chou Kun-Ta,Hsu Chia-Chen 대한천식알레르기학회 2022 Allergy, Asthma & Immunology Research Vol.14 No.3

Purpose: Current clinical guidelines are unclear regarding the association of cardiovascular medication with the risk of acute exacerbation (AE) in patients with asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO). Methods: We conducted a retrospective cohort study by interrogating the claims database of Taipei Veterans General Hospital. Patients with coexistent fixed airflow limitation and asthma were enrolled as an ACO cohort between 2009 and 2017. Exposure to cardiovascular medications, including angiotensin converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), non-selective beta-blockers, cardioselective beta-blockers, dihydropyridine (DHP) calcium channel blockers (CCBs), and non-DHP CCBs, in 3-month period each served as time-dependent covariates. Patients receiving a cardiovascular medication ≥ 28 cumulative daily doses were defined as respective cardiovascular medication users. Patients were followed up until December 31, 2018. The primary endpoint was severe AE, defined as hospitalization or emergency department visit for either asthma, COPD, or respiratory failure. The secondary outcome was moderate AE. Results: The final study cohort consisted of 582 ACO subjects, with a mean follow-up period of 2.98 years. After adjustment, ARB (hazard ratio [HR], 0.64, 95% confidence interval [CI], 0.44–0.93, P = 0.019), cardioselective beta-blocker (HR, 0.29, 95% CI, 0.11–0.72, P = 0.008) and DHP CCB (HR, 0.66, 95% CI, 0.45–0.97, P = 0.035) therapies were associated with lower risks of severe AE. ARB (HR, 0.42, 95% CI, 0.30–0.62, P < 0.001) and DHP CCB (HR, 0.55, 95% CI, 0.38–0.80, P = 0.002) therapies were associated with lower risks of moderate AE. Cardioselective beta-blockers, ARBs, and DHP CCBs were associated with lower risks of severe AE in frequent exacerbators. ACEI, non-selective beta-blocker, or non-DHP CCB use did not change the risk of severe AE. Conclusions: ARB, cardioselective beta-blocker, and DHP CCB therapies may lower the risk of AE in patients with ACO.

Predictors of Positive Bone Metastasis in Newly Diagnosed Prostate Cancer Patients

Chien, Tsu-Ming,Lu, Yen-Man,Geng, Jiun-Hung,Huang, Tsung-Yi,Ke, Hung-Lung,Huang, Chun-Nung,Li, Ching-Chia,Chou, Yii-Her,Wu, Wen-Jeng,Huang, Shu-Pin Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.3

Background: The prevalence of prostate cancer (PCa) has been increasing in recent years. Treatment strategies are largely based on the results of bone scan screening. Therefore, our aim was to investigate predictors of positive bone metastasis in newly diagnosed PCa patients. Materials and Methods: After extensive review, 336 consecutive patients newly diagnosed with PCa between April 2010 and November 2013 at our institution were enlisted in the study. Patients were divided into two groups according to bone scan results. Univariate analyses (Chi-square test for discrete variables and independent t-test for continuous variables) were applied to determine the potentially significant risk factors associated with distant bone metastasis. Binary logistic regression analyses were used to further investigate the influence of these factors on bone metastasis. Results: The patient mean age was $71.9{\pm}8.6years$ (range: 48 to 94 years). The mean prostate specific antigen (PSA) level and biopsy Gleason score were $260.2{\pm}1107.8ng/mL$ and $7.4{\pm}1.5$, respectively. The body mass index (BMI) for the series was $24.5{\pm}3.4kg/m^2$. Sixty-four patients (19.0%) had a positive bone scan result. Patients with positive bone scan results had a significantly lower BMI ($23.3{\pm}3.5$ vs. $24.8{\pm}3.3$; p=0.003), a higher Gleason score ($8.5{\pm}1.1$ vs. $7.1{\pm}1.5$; p < 0.001), and a higher PSA level ($1071.3{\pm}2337.1$ vs. $69.4{\pm}235.5$; p < 0.001) than those without bone metastasis. Multivariate logistic regression analysis employing the above independent predictors demonstrated that a Gleason score of ${\geq}7$, clinical stage ${\geq}T3$, $BMI{\leq}22kg/m^2$, and an initial PSA level of ${\geq}20ng/mL$ were all independent predictors of bone metastasis. Conclusions: A bone scan might be necessary in newly diagnosed PCa patients with any of the following criteria: clinical stage T3 or higher, a Gleason score of 7 or higher, BMI equal to or less than 22, and a PSA level of 20 or higher.