Clinical Features and Computed Tomography Characteristics of Non-Klebsiella pneumoniae Liver Abscesses in Elderly (>65 Years) and Nonelderly Patients

Chih-Weim Hsiang,Wei-Chou Chang,Chang-Hsien Liu,Hsiu-Lung Fan,Kai-Hsiung Ko,Chih-Yung Yu,Hong-Hau Wang,Wen-I Liao,Hsian-He Hsu 연세대학교의과대학 2015 Yonsei medical journal Vol.56 No.2

Purpose: To compare the clinical and computed tomography (CT) appearances of liver abscesses caused by non-Klebsiella pneumoniae bacterial pathogens in elderly and nonelderly patients. Materials and Methods: Eighty patients with confirmed non-Klebsiella pneumoniae liver abscesses (non-KPLAs) were enrolled and dividedinto two age groups: elderly (age ≥65 years, n=42) and nonelderly (age <65 years, n=38). Diagnosis of non-KPLA was established by pus and/or blood culture. We compared clinical presentations, outcomes, and CT characteristics of the two groups, and performed multivariate analysis for significant variables and receiver-operating-characteristic analysis to determine the cutoff value of abscess diameter for predicting non-KPLA. Results: Elderly patients with non-KPLA were associatedwith a longer hospital stay (p<0.01). Regarding etiology, biliary sources had a strong association in the elderly group (p<0.01), and chronic liver diseases were relatedto the nonelderly group (p<0.01). Non-KPLAs (52.5%) tended to show a large, multiloculated appearance in the elderly group and were associated with bile duct dilatation (p<0.01), compared with the nonelderly group. The abscess diameter (cutoff value, 5.2 cm; area under the curve, 0.78) between the two groups was predicted. In multivariate analysis, underlying biliary tract disease [odds ratio (OR), 3.58, p<0.05], abscess diameter (OR, 2.40, p<0.05), and multiloculated abscess (OR, 1.19, p<0.01) independently predicted elderly patients with non-KPLA. Conclusion:In the elderly patients with non-KPLA, a large, multiloculated abscess with a diameter greater than 5.2 cm was the predominant imaging feature.

Effects of the addition of minute amounts of alumina on the microstructure and sintering behavior of yttria stabilized tetragonal zirconia polycrystals ceramic via a co-precipitation process

Chih-Cheng Chen,Chang-Min Zhou,Hsing-I Hsiang 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.3

It is feasible to add homogeneously minute amounts (0.25 wt%) of Al₂O₃ into 3 mol% yttria stabilized tetragonal zirconia polycrystals using a co-precipitation procedure to produce precursory gel nano-powders. X-ray diffraction, scanning electron microscopy, high-angle annular dark-field-field emission gun transmission electron microscopy, relative density determination, shrinkage, and resistivity measurements using impedance spectroscopy were combined to elucidate the microstructure and sintering behavior of zirconia ceramics produced using 0.25 wt% added Al₂O₃, possibly the limit of solubility of Al₂O₃ in the ZrO₂ structure. Two modes of sintering behavior may be described as: (I) The total solid solution of Al₂O₃ in the solid solution of ZrO₂ structure via a precursory co-precipitation procedure; calcining at 800 oC and sintering at 1275 oC can be shown to indicate the viable solubility of Al₂O₃ in the ZrO₂ structure, designated as stage I of the thermal treatment; and (II) At the higher sintering temperature, above 1275 oC, the segregation of Al₂O₃ at triple junction occurs. Higher bulk and grain boundary resistivity values are found for the sample sintered at 1275 oC, which probably resulted from the dissolution of Al₂O₃ in the ZrO₂ structure. It is feasible to add homogeneously minute amounts (0.25 wt%) of Al₂O₃ into 3 mol% yttria stabilized tetragonal zirconia polycrystals using a co-precipitation procedure to produce precursory gel nano-powders. X-ray diffraction, scanning electron microscopy, high-angle annular dark-field-field emission gun transmission electron microscopy, relative density determination, shrinkage, and resistivity measurements using impedance spectroscopy were combined to elucidate the microstructure and sintering behavior of zirconia ceramics produced using 0.25 wt% added Al₂O₃, possibly the limit of solubility of Al₂O₃ in the ZrO₂ structure. Two modes of sintering behavior may be described as: (I) The total solid solution of Al₂O₃ in the solid solution of ZrO₂ structure via a precursory co-precipitation procedure; calcining at 800 oC and sintering at 1275 oC can be shown to indicate the viable solubility of Al₂O₃ in the ZrO₂ structure, designated as stage I of the thermal treatment; and (II) At the higher sintering temperature, above 1275 oC, the segregation of Al₂O₃ at triple junction occurs. Higher bulk and grain boundary resistivity values are found for the sample sintered at 1275 oC, which probably resulted from the dissolution of Al₂O₃ in the ZrO₂ structure.

The Dilemmas of Social Housing System in the Face of Property-Led Urban Regeneration

Cassidy I-Chih Lan,Chen-Jai Lee 한국주거학회 2015 한국주거학회 국제학술대회논문집 Vol.2015 No.4

Risk of Mental Illnesses in Patients With Hypopituitarism: A Nationwide Population-Based Cohort Study

I-Hua Wei,Chih-Chia Huang 대한신경정신의학회 2022 PSYCHIATRY INVESTIGATION Vol.19 No.6

Objective The associations of mental illnesses and hypopituitarism have been reported. But, pituitary disorders are rare. The epidemiological studies have rarely addressed these associations between pituitary disorder and mental illnesses. Until now, no cohort study has been conducted to investigate the association.Methods We performed a nationwide, retrospective cohort study using the Taiwanese National Health Insurance Program dataset to analyze this relationship. In total, 1,194 patients diagnosed with hypopituitarism between 2000 and 2013 were identified. For the control group, 4,776 individuals without hypopituitarism and psychotic diseases were matched (1:4) according to age, sex, and index date. A Cox proportional hazards model was used to determine the adjusted hazard ratio (aHR).Results Patients with hypopituitarism had a significantly higher risk of incident depression and anxiety disorders than those without hypopituitarism. The aHRs of depressive and anxiety disorders were 2.98 and 1.67, respectively, for the hypopituitarism cohort. Furthermore, the risk of both hypopituitarism-associated depressive and anxiety disorders was significantly high in female subjects and subjects aged ≥18 years. A statistically significant increase was not observed in the risk of bipolar disorders, dementia, or schizophrenia in the hypopituitarism group compared with the control group.Conclusion Although psychiatric morbidities were uncommon for the hypopituitarism cohort, the risk of developing depressive and anxiety disorders was significantly higher in those with hypopituitarism than in those without hypopituitarism.

Collagen II cross-linked glycosaminoglycans as scaffold for chondrocyte expansion

Chih-Sheng Ko,I-Ming Chu 한국생물공학회 2008 한국생물공학회 학술대회 Vol.2008 No.4

Effects of aging on the phase transformation and sintering properties of coprecipitated Al₂O₃-ZrO₂ powders

Chih-Cheng Chen,Hsing-I Hsiang,Fu-Su Yen 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.1

In this study, the effects of aging on the crystalline phases, crystallite sizes and sintering properties of coprecipitated Al₂O₃- ZrO₂ powders are investigated using thermogravimetry (TG), differential thermal analysis (DTA), X-ray diffractometry (XRD), dilatometry, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Coprecipitated Al₂O₃- ZrO₂ powder aging in the solution promoted the dissolution and reprecipitation process, which resulted in the boehmite structure subsequently transforming into bayerite. The densification and microstructural development of the coprecipitated Al₂O₃-ZrO₂ powders were dependent upon the aging time which shifted the θ→α-Al₂O₃ phase transformation to a higher temperature, lowered the crystallite growth rate, and prevented the occurrence of intragranular ZrO₂ particles during sintering. In this study, the effects of aging on the crystalline phases, crystallite sizes and sintering properties of coprecipitated Al₂O₃- ZrO₂ powders are investigated using thermogravimetry (TG), differential thermal analysis (DTA), X-ray diffractometry (XRD), dilatometry, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Coprecipitated Al₂O₃- ZrO₂ powder aging in the solution promoted the dissolution and reprecipitation process, which resulted in the boehmite structure subsequently transforming into bayerite. The densification and microstructural development of the coprecipitated Al₂O₃-ZrO₂ powders were dependent upon the aging time which shifted the θ→α-Al₂O₃ phase transformation to a higher temperature, lowered the crystallite growth rate, and prevented the occurrence of intragranular ZrO₂ particles during sintering.

A Distributed and Scalable Time Slot Allocation Protocol for Wireless Sensor Networks

Chih-Kuang Lin,Zadorozhny, Vladimir I,Krishnamurthy, Prashant V,Ho-Hyun Park,Chan-Gun Lee IEEE 2011 IEEE TRANSACTIONS ON MOBILE COMPUTING Vol.10 No.4

<P>There are performance deficiencies that hamper the deployment of Wireless Sensor Networks (WSNs) in critical monitoring applications. Such applications are characterized by considerable network load generated as a result of sensing some characteristics of the monitored system. Excessive packet collisions lead to packet losses and retransmissions, resulting in significant overhead costs and latency. In order to address this issue, we introduce a distributed and scalable scheduling access scheme that mitigates high data loss in data-intensive sensor networks and can also handle some mobility. Our approach alleviates transmission collisions by employing virtual grids that adopt Latin Squares characteristics to time slot assignments. We show that our algorithm derives conflict-free time slot allocation schedules without incurring global overhead in scheduling. Furthermore, we verify the effectiveness of our protocol by simulation experiments. The results demonstrate that our technique can efficiently handle sensor mobility with acceptable data loss, low packet delay, and low overhead.</P>

Enhancing concept comprehension in a web-based course using a framework integrating the learning cycle with variation theory

Chih-Chao Hsu,Tzone-I Wang 서울대학교 교육연구소 2014 Asia Pacific Education Review Vol.15 No.2

Concept comprehension is an important foundation for more complex thoughts. To enhance concept comprehension, teachers of traditional classrooms have been using instructional strategies and specific course designs, which have been proven effective. It initiates a hypothesis that integrating instructional strategies in the course designs of an e-learning system would improve the effectiveness of concept comprehension. The purpose of this study is to propose a framework that integrates the learning cycle with variation theory in the course design of a web-based e-learning system to prove the hypothesis. A pretest and posttest quasi-experimental design is employed to test whether the framework is feasible. Two types of web-based courses are designed for the experiments: a course designed according to a science textbook and another course designed using the framework. The participants in this study were 120 fifth-grade students in Taiwan. The results of the experiments show that the average scores of the experimental group, using the course designed with the framework, are significantly higher than that of the control group, using the course designed without any instructional strategy, on comprehension of course concepts. This confirms that the coherent, explicit and systematic framework is feasible for designing web-based e-learning courses for effectively enhancing concept comprehension as well as the evidence to prove the hypothesis.

Investigate the Mechanical and Biological Activities of PVA Membranes

( Chih-chang Yeh ),( Kai-chen Hu ),( Tsung-yan Tsai ),( Chu-wen Shao ),( Ruey-shyang Chen ),( Hsin-i Chang ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.1

Polyvinyl alcohol (PVA) is a water-soluble synthetic polymer and which has high tensile strength and flexibility, low toxicity and good biocompatibility for the application of soft tissue engineering. Generally, PVA can be crosslinked to form 3-D structure by a variety of methods, such as chemical crosslinking, irradiation or the freeze-thaw techniques. In contrast, chemical-crosslinked PVA structure has good elasticity, high water content, and stability at room temperature but most of crosslinking reagents such as glutaradehyde have high cytotoxicity. In here, we used low toxic genipin as crosslinking reagent for the formulation of PVA membrane. Thermal behavior and mechanical properties of genipin-crosslinked PVA membrane have been measured by thermo gravimetric analyzer and universal testing machine. Genipin-crosslinked PVA membrane had a smooth surface and the contact angel was about 67°. The swelling test displayed that genipin-crosslinked PVA membrane had high water content (130%) and the increase of PVA molecular weight can slightly improve water content. Moreover, dried genipin-crosslinked PVA membrane presented higher tensile strength (7.21MPa) but lower ductility (3.4%) than hydrated membrane (3.9MPa and 302.4%). Interestingly, rehydration of dried PVA membrane can maintain similar ductility to original hydrated membrane but the tensile strength was reduced by 40%. Therefore, drying process may break some hydrogen bonding between the polymer structure of PVA membrane. In MTT assay, there was some toxicity remained in genipin-PVA membrane but cell survivability was 1.5-1.9 fold higher than glutaradehyde-crosslinked PVA membrane. Overall, genipin-crosslinked PVA membrane showed low toxicity, good cell attachment and growth of human foreskin fibroblasts. After the cell culture study, the degradation of genipin-crosslinked PVA membrane was investigated by scanning electron microscope. Therefore, genipin-crosslinked PVA membrane is a biodegradable material and which can apply in soft tissue engineering due to its good elastic behavior.

Preparation and characterization of Y-TZP powders coated with alumina

Chih-Cheng Chen,Shu-Wei Hsu,Hsing-I Hsiang 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.2

In this study, alumina was coated onto yttria tetragonally stabilized zirconia (Y-TZP)core powder using aluminum nitrate with urea in an aqueous solution. Boehmite coating onto the surface of Y-TZP powders was confirmed using transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy and zeta potential measurements. The sintering behaviors of Y-TZP powders with and without an alumina coating were investigated using a dilatometer and scanning electron microscopy (SEM). Boehmite coating onto the surface of Y-TZP powders significantly improved the densification of the resulting ceramic bodies. The relative density of the Y-TZP with a boehmite coating sintered at 1350oC can reach 97.3%. In this study, alumina was coated onto yttria tetragonally stabilized zirconia (Y-TZP)core powder using aluminum nitrate with urea in an aqueous solution. Boehmite coating onto the surface of Y-TZP powders was confirmed using transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy and zeta potential measurements. The sintering behaviors of Y-TZP powders with and without an alumina coating were investigated using a dilatometer and scanning electron microscopy (SEM). Boehmite coating onto the surface of Y-TZP powders significantly improved the densification of the resulting ceramic bodies. The relative density of the Y-TZP with a boehmite coating sintered at 1350oC can reach 97.3%.