68 results on '"Kao, T."'
Search Results
2. GAD65 as a potential marker for cognitive performance in an adult population with prediabetes.
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Tsai, C -K, Kao, T -W, Lee, J -T, Wang, C -C, Chou, C H, Liang, C -S, Yang, F -C, and Chen, W -L
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GLUTAMATE decarboxylase , *HEALTH & Nutrition Examination Survey , *COGNITION disorders , *REACTION time , *CENTRAL nervous system - Abstract
Background Diabetes mellitus (DM) is a well-known risk factor for cognitive dysfunction in aged populations. However, there are inconsistent reports about impaired fasting glucose or prediabetes as an independent risk factor for cognitive function. Glutamic acid decarboxylase 65 (GAD65) is the key enzyme responsible for γ-aminobutyric acid synthesis in the central nervous system. Antibodies against GAD65 (GAD65Abs) are not only detected in approximately 80% of early-onset type 1 DM, but also linked to several neurological disorders. Aim This study aims to investigate the association between GAD65Ab titer levels and cognitive performance. In addition, we assessed the effect of GAD65Ab on cognitive function in adults with normal fasting glucose, prediabetes and DM. Methods A total of 328 subjects aged 49.10 ± 5.72 years were enrolled from the Third Health and Nutrition Examination Survey dataset. Cognitive performance was assessed by three computerized neurobehavioral tests, including the serial digit learning test, simple reaction time test (SRTT) and symbol-digit substitution test (SDST). Results Subjects with higher GAD65Ab titers had significantly poorer cognitive function in the SRTT and SDST (P < 0.05). Additionally, GAD65Ab was associated with cognitive decline in non-diabetic adults after adjusting for a number of relevant variables (P < 0.05 in both SRTT and SDST). Conclusions These results indicate that GAD65Ab may be a potential marker for cognitive impairment in non-diabetic adults. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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3. Mass transport during photochemical oxidation of Hg1-xCdxTe.
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Kao, T.-M. and Sigmon, T. W.
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PHOTOCHEMICAL oxidants , *MERCURY compounds , *THIN films - Abstract
Presents a study which determined the mechanism of photochemical oxide growth of Hg[sub1-x]Cd[subx]Te epilayers. Photochemical oxidation of the films; Results and discussion; Conclusions.
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- 1988
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4. Associations between serum total bilirubin levels and functional dependence in the elderly.
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Kao, T. W., Chou, C. H., Wang, C. C., Chou, C. C., Hu, J., and Chen, W. L.
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ATHEROSCLEROSIS risk factors , *GOVERNMENT agencies , *ASPARTATE aminotransferase , *BILIRUBIN , *C-reactive protein , *EPIDEMIOLOGY , *INFLAMMATION , *INTERLEUKINS , *INTERNAL medicine , *MEDICAL care , *MEDICAL screening , *PATIENTS , *QUESTIONNAIRES , *RACE , *SURVEYS , *DATA analysis , *ALANINE aminotransferase , *PHYSICAL activity , *FUNCTIONAL assessment , *DESCRIPTIVE statistics ,STROKE risk factors - Abstract
Background Many studies support the role of bilirubin as a cytoprotector in chronic inflammatory diseases, such as stroke and atherosclerosis. Aim To investigate the relationship between serum total bilirubin levels and functional dependence in older adults. Methods Data from the National Health and Nutrition Examination Survey (1999-2002) pertaining to 2235 old adults were analysed. All participants had given a household interview, providing information of five major domains on self-reported functional status (activities of daily living, instrumental activities of daily living, leisure and social activities, lower extremity mobility and general physical activities), had completed serum total bilirubin measurement, and a questionnaire regarding personal health. Poor performance was defined as experiencing difficulty with one or more items in a given domain. Functional dependence was defined as having three or more poor performances in the five major domains. Multiple logistic regression was performed together with quartile-based stratified odds ratio ( OR) comparison and trend tests. Results The OR of functional dependence for each standard deviation increment in the serum total bilirubin level was 0.56 ( P = 0.002). After additional adjustment, the inverse association remained essentially unchanged. In quartile-based analysis, participants with higher quartiles of serum total bilirubin tended to have lower ORs of functional dependence. The trends of lower likelihood of functional dependence across increasing quartiles of the serum total bilirubin level were statistically significant ( P < 0.05 for all trends). Conclusions Higher serum total bilirubin levels were associated with lower likelihood of functional dependence in older adults. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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5. âDigitallyâAddressable Focusing ofLight into a Subwavelength Hot Spot.
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Kao, T. S., Rogers, E. T. F., Ou, J. Y., and Zheludev, N. I.
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PLASMONS (Physics) , *METAMATERIALS , *PHASE modulation , *WAVELENGTHS , *PHASE transitions - Abstract
We show that a plasmonic metamaterial can act as a far-fieldtonear-field transformer that focuses a free-space beam of light intoa subwavelength energy hot spot at a prescribed location with a spotsize only a small fraction of the wavelength. The hot spot positionon the metamaterial can be prescribed and moved at will from one metamoleculeof the array to another in a âdigitalâ fashion simplyby modulating the input phase profile, thus providing new opportunitiesfor imaging and optical data processing. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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6. Functional role of exercise-induced cortical organization of sensorimotor cortex after spinal transection.
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Kao, T., Shumsky, J. S., Knudsen, E. B., Murray, M., and Moxon, K. A.
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SENSORIMOTOR cortex , *SPINAL cord , *NEURAL circuitry , *ELECTROPHYSIOLOGY , *LABORATORY rats , *LOCOMOTOR control - Abstract
Spinal cord transection silences neuronal activity in the deafferented cortex to cutaneous stimulation of the body and untreated animals show no improvement in functional outcome (weight-supported stepping) with time after lesion. However, adult rats spinalized since neonates that receive exercise therapy exhibit greater functional recovery and exhibit more cortical reorganization. This suggests that the change in the somatotopic organization of the cortex may be functionally relevant. To address this issue, we chronically implanted arrays of microwire electrodes into the infragranular layers of the hindlimb somatosensory cortex of adult rats neonatally transected at T8/T9 that received exercise training (spinalized rats) and of normal adult rats. Multiple, single neuron activity was recorded during passive sensory stimulation, when the animals were anesthetized, and during active sensorimotor stimulation during treadmill-induced locomotion when the animal was awake and free to move. Our results demonstrate that cortical neurons recorded from the spinalized rats that received exercise 1) had higher spontaneous firing rates, 2) were more likely to respond to both sensory and sensorimotor stimulations of the forelimbs, and also 3) responded with more spikes per stimulus than those recorded from normal rats, suggesting expansion of the forelimb map into the hindlimb map. During treadmill locomotion the activity of neurons recorded from neonatally spinalized rats was greater during weight-supported steps on the treadmill compared with the neuronal activity during nonweight supported steps. We hypothesize that this increased activity is related to the ability of the animal to take weight supported steps and that, therefore, these changes in cortical organization after spinal cord injury are relevant for functional recovery. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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7. Graptopetalum paraguayense e. Walther leaf extracts protect against brain injury in ischemic rats.
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Kao T, Ou Y, Raung S, Chen W, Yen Y, Lai C, Chou S, and Chen C
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As practice in folk medicine, Graptopetalum paraguayense E. Walther possesses several biological/pharmacological activities including hepatoprotective, anti-oxidant, and anti-inflammatory. We investigated the neuroprotective potential of Graptopetalum paraguayense E. Walther leaf extracts on inflammation-mediated ischemic brain injury. Water (GWE), 50% alcohol (GE50) extracts of Graptopetalum paraguayense E. Walther, and extracts obtained from further extraction of GE50 with ethyl acetate (GEE) were used. Oral administration of GEE, but not GWE or GE50, for 2 weeks protected animals against cerebral ischemia/reperfusion brain injury. The neuroprotective effect of GEE was accompanied by reductions in brain infarction, neurological deficits, caspase-3 activity, malondialdehyde content, microglia activation, and inducible nitric oxide synthase (iNOS) expression. Since microglia-mediated inflammation plays critical roles in ischemic brain injury, anti-inflammatory potential of Graptopetalum paraguayense E. Walther leaf extracts was further investigated on lipopolysaccharide (LPS)/interferon-[gamma] (IFN-[gamma]-activated BV-2 microglial cells. GEE decreased H2O2- and LPS/IFN-[gamma]-induced free radical generation and LPS/IFN-[gamma]-induced iNOS expression. Mechanistic study revealed that the neuroactive effects of GEE were markedly associated with anti-oxidative potential, activation of serine/threonine and tyrosine phosphatases, and down-regulation of extracellular signal-regulated kinase, c-Jun N-terminal kinase, p38, Akt, Src, Janus kinase-1, Tyk2, signal transducer and activator of transcription-1, and NF-[kappa]B and might be attributed to the presence of polyphenolic compounds such as gallic acid, genistin, daidzin, and quercetin. Together, our findings point out its potential therapeutic strategies that target microglia activation, oxidative stress, and iNOS expression to reduce ischemic brain injury and suggest that Graptopetalum paraguayense E. Walther leaf extracts represent a valuable source for the development of neuroprotective agents. [ABSTRACT FROM AUTHOR]
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- 2010
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8. Multiple structural changes in the tail behavior: Evidence from stock index futures returns
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Lin, C.-H. and Kao, T.-C.
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STOCK index futures , *NONLINEAR statistical models , *VALUE engineering , *FUTURES market - Abstract
Abstract: The study provides an approach of nonlinear analysis for detecting multiple structural changes in the tails of financial returns distributions. The proposed approach can simultaneously determine the number of structural breaks in a series of tail-indexes and estimate the mean tail-index levels in distinct regimes. The method is applied to the tail behavior of DJIA futures returns. The sample period covered various recent financial crises, and ran from October 1999 to December 2003, enabling assessment of the relationships between changes in the tail shape of returns distribution and known extreme events in financial markets. The empirical results demonstrate the existence of at least one break point in the left and common tails of the DJIA futures returns distribution during the sample period, and the mean tail-index levels in different regimes classified by estimated break points display an increase in the left and common tails that coincides the phenomenon of gradually decreasing financial turbulence in DJIA futures contracts. The empirical evidence indicates that the structural changes in the tail behavior of the distribution of DJIA futures returns are associated more with negative shocks than positive ones, creating differences in risk management between long and short investors in futures markets. [Copyright &y& Elsevier]
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- 2008
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9. CDK1 promotes cell proliferation and survival via phosphorylation and inhibition of FOXO1 transcription factor.
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Liu, P., Kao, T. P., and Huang, H.
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CELL proliferation , *PHOSPHORYLATION , *RADIOLIGAND assay , *CYCLIN-dependent kinases , *CHEMICAL reactions - Abstract
The forkhead box O (FOXO) transcription factor FOXO1 functions as a tumor suppressor by regulating expression of genes involved in apoptosis, cell cycle arrest and oxidative detoxification. Here, we demonstrate that cyclin-dependent kinase 1 (CDK1) specifically phosphorylates FOXO1 at serine 249 (S249) in vitro and in vivo. Coimmunoprecipitation assays demonstrate that both endogenous CDK1 and ectopically expressed CDK1 form a protein complex with FOXO1 in prostate cancer (PCa) cells. In vitro protein binding assays reveal that CDK1 interacts directly with FOXO1. Accordingly, overexpression of CDK1 inhibits the transcriptional activity of FOXO1 in PCa cells through S249 phosphorylation on FOXO1. Consistent with the roles of FOXO3a and FOXO4 (two other members of the FOXO family) in cell cycle regulation, forced expression of FOXO1 causes a delay in the transition from G2 to M phase. This effect is blocked completely by overexpression of CDK1 and cyclin B1. Ectopic expression of constitutively active CDK1 also inhibits FOXO1-induced apoptosis in PCa cells. Moreover, we demonstrate that the inhibitory effect of FOXO1 on Ras oncogene-induced colony formation in fibroblasts is diminished by overexpression of CDK1. Given that CDK1 and cyclin B1 are often overexpressed in human cancers including PCa, our findings suggest that aberrant activation of CDK1 may contribute to tumorigenesis by promoting cell proliferation and survival via phosphorylation and inhibition of FOXO1.Oncogene (2008) 27, 4733–4744; doi:10.1038/onc.2008.104; published online 14 April 2008 [ABSTRACT FROM AUTHOR]
- Published
- 2008
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10. Study of the optical response of phase-change recording layer with zinc oxide nanostructured thin film.
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Kao, T. S., Fu, Y. H., Hsu, H. W., and Tsai, D. P.
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ZINC oxide thin films , *THIN films , *OPTICAL properties , *NANOSTRUCTURED materials , *METALLIC oxides , *OPTICAL disks - Abstract
Recently, use of nanostructured materials as a near-field optical active layer has attracted a lot of interest. The non-linear optical properties and strong enhancements of metallic oxide nanostructured thin films are key functions in applications of promising nanophotonics. For the importance of ultra-high density optical data storage, we continue investigating the ultra-high density recording property of near-field optical disk consisting of zinc oxide (ZnO x) nanostructured thin film. A carrier-to-noise ratio above 38 dB at a recording mark size of 100 nm can be obtained in the ZnO x near-field optical disk by a DVD driver tester directly. In this article, we use an optical pump-probe system (static media tester) to measure the optical response of a phase-change recording layer (Ge2Sb2Te5) and demonstrate the high contrast of optical recording with a ZnO x nanostructured thin film in short pulse durations. Also, we investigate the dependence of writing power and the optical response in conventional re-writable recording layers and the phase-change material with ZnO x nanostructured thin film. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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11. Study of the optical response of phase-change recording layer with zinc oxide nanostructured thin film.
- Author
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Kao, T. S., Fu, Y. H., Hsu, H. W., and Tsai, D. P.
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THIN films , *NANOPHOTONICS , *OPTICAL disks , *METALLIC oxides , *OPTICAL disk drives - Abstract
Recently, use of nanostructured materials as a near-field optical active layer has attracted a lot of interest. The non-linear optical properties and strong enhancements of metallic oxide nanostructured thin films are key functions in applications of promising nanophotonics. For the importance of ultra-high density optical data storage, we continue investigating the ultra-high density recording property of near-field optical disk consisting of zinc oxide (ZnO x) nanostructured thin film. A carrier-to-noise ratio above 38 dB at a recording mark size of 100 nm can be obtained in the ZnO x near-field optical disk by a DVD driver tester directly. In this article, we use an optical pump-probe system (static media tester) to measure the optical response of a phase-change recording layer (Ge2Sb2Te5) and demonstrate the high contrast of optical recording with a ZnO x nanostructured thin film in short pulse durations. Also, we investigate the dependence of writing power and the optical response in conventional re-writable recording layers and the phase-change material with ZnO x nanostructured thin film. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
12. Evanescent field enhancement due to plasmonic resonances of a metamaterial slab.
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Chiu, K. P., Kao, T. S., and Tsai, D. P.
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SURFACE plasmon resonance , *EXCITON theory , *METAMATERIALS , *SOLID state electronics , *THICK films - Abstract
The characteristics of plasmonic resonance in a dielectric-sandwiched metamaterial film at visible wavelengths of 650 and 568 nm have been investigated (for both p- and s-polarized light). Our calculated results demonstrate that each mode of plasmonic resonance has maximum resonance strength at a particular film thickness of the metamaterial. We also demonstrated that the effect of evanescent field enhancement is due to plasmonic resonances of the sandwiched metamaterial system. And the stronger the plasmonic resonance strength the larger the evanescent field is enhanced at the interfaces of the metamaterial film. Also we see that the plasmonic resonances in a sandwiched metamaterial are influenced not only by the materials that constitute the interfaces but also by the thickness of surrounding dielectrics or distance between evanescent light source and metamaterial film. Finally, our results show that there might be an effective light propagation length that will let the coupling efficiency between evanescent light source and SPs resonance become a maximum. These properties of plasmonic resonances to structure parameters of metamaterial film and its surrounding dielectrics provide a useful way to control the optical responses of an optoelectronic device when the wavelength of light source is fixed. That is, by suitably choosing light polarizations, thickness of the metamaterial thin film or the surrounding dielectrics and the position of evanescent light source, it is possible to modulate the plasmonic resonance wavenumber or resonance strength of the system. Therefore, the optical responses of the system can be modulated. Our results will be helpful for the structure design to control the behaviours of coupled plasmonic resonances and consequently the optical properties of the dielectric-sandwiched metamaterial film. [ABSTRACT FROM AUTHOR]
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- 2008
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13. Characterization of diffraction enhanced imaging contrast in plants
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Kao, T., Liu, C.-J., Yu, X.-H., Young, L., Connor, D., Dilmanian, A., Parham, C., Reaney, M., and Zhong, Z.
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TOMOGRAPHY , *MEDICAL radiography , *PLANT cells & tissues , *CONDUCTING tissues of bryophytes - Abstract
Abstract: Diffraction Enhanced Imaging (DEI) was used to characterize the extinction contrast coefficient of plant tissues. Single-cells were imaged with planar DEI. The organized structures of the plant cell walls were found to exhibit significant extinction contrast and were readily visualized using DEI. Extinction properties of different tissue types in plant roots, stems and seeds were characterized by DEI in Computed Tomography (DEI–CT) mode at the peak of the analyzer-rocking curve. DEI–CT yields different extinction coefficients for different cell types, resulting in high-contrast, high-resolution images of internal anatomical structures of plants. [Copyright &y& Elsevier]
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- 2007
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14. Ask the expert. Sexual health education disparities in Asian American adolescents.
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Kao T and McDowell BM
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- 2006
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15. Health-related behaviors in young military smokers.
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Kao T, Lynch JP, Hanson K, Lynch, John P, Hanson, Kevin, and Kao, Tzu-Cheg
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This cross-sectional study examined the association between smoking and other health-related risk behaviors, individually as well as in clusters, across branches of military service in the higher risk ages of 18 to 25 years old within the 1998 Department of Defense Survey of Health-Related Behaviors among Military Personnel. Examination of the demographic variables revealed that, in general, smokers tended to be single, white, enlisted men in the 18- to 20-year age group with less education and serving in the Army or Marine Corps. Our findings support that there is an increased likelihood of co-occurrence of substance use along with other negative health-related risk behaviors found in military members. It may be practical and necessary to develop a focused survey given to those attending smoking cessation interventions, or perhaps to smokers in general, which attempts to identify associated risk behaviors and channel clients accordingly. [ABSTRACT FROM AUTHOR]
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- 2004
16. Three dimensional matrix stiffness orchestrates the alteration of viscoelasticity in human mesenchymal stem cells.
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Kao, T. and Lee, O.
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HUMAN stem cells , *MESENCHYMAL stem cells , *VISCOELASTICITY - Published
- 2021
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17. Conscious Recovery Response in Post–Hepatic Transplant as a Function of Time-Related Acute Hepatic Encephalopathy
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Kao, T.-L. and Wang, C.-C.
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LIVER transplantation , *SURGICAL complications , *ORGAN donors , *BLOOD coagulation disorders , *HEPATIC encephalopathy , *HERNIA , *HYPERAMMONEMIA , *PREOPERATIVE period , *DISEASES - Abstract
Abstract: Background: H Coma due to acute hepatic failure produces a high mortality rate with rapid progression of cerebral edema and brain herniation. Early transplantation increases survival of patients with acute hepatic encephalopathy. In previous studies, scant attention has focused on the conscious recovery time after living donor liver transplantation (ldlt) and whether the conscious recovery time was directly proportional to the length of coma before transplantation. Patients and methods: We have reported herein three adult patients with decompensated chronic end-stage liver disease who underwent right lobe LDLT. Their general conditions had markedly deteriorated; two patients displayed massive ascites. All three subjects displayed grade IV encephalopathy with endotracheal intubation and intensive care management. Their biochemical data revealed hyperammonemia, marked cholestasis, and coagulopathy. Results: After LDLT the patients recovered from coma at a mean time similar to that in coma. Preoperatively the patients exhibited acute deep coma with respiratory failure on preoperative days 5, 3, and 1 with consciousness regained on postoperative day 5, 3 and 1, respectively. Conclusion: We suggest that patients with acute deep coma (grade IV), who were formerly regarded as irreversible, benefit with LDLT, preventing worsening of complications, and that shows a time-dependent recovery the pretransplant comatose status. [Copyright &y& Elsevier]
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- 2012
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18. Metamaterial as a controllable template for nanoscale field localization.
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Kao, T. S., Huang, F. M., Chen, Y., Rogers, E. T. F., and Zheludev, N. I.
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EFFECT of radiation on lasers , *ELECTROMAGNETISM , *ELECTRIC radiation , *SOLAR radiation polarization , *NANOELECTRONICS , *METAMATERIALS - Abstract
We report that subwavelength localization of light in the near-field of a double-periodic photonic metamaterial may be efficiently controlled by the polarization and wavelength of the incident radiation. A dramatic variation in the periodic near-field landscapes, including a transition from a pattern of isolated subwavelength plasmon hot-spots to a blurred, low contrast pattern, accompanied by a change in the pattern’s symmetry has been observed in the proximity of an aluminum nanowire “fish-scale” nanostructure. Hot-spots as small as 0.23λ have been achieved and their position has been controlled by tuning the wavelength of incident light across the dipole absorption resonance of the metamaterial. A simple switch of the polarization state can lead to a spatial period doubling in the landscape pattern. [ABSTRACT FROM AUTHOR]
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- 2010
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19. Native oxide encapsulation for annealing boron-implanted Hg1-xCdxTe.
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Kao, T.-M. and Sigmon, T. W.
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MERCURY cadmium tellurides , *MASS spectrometry - Abstract
We report for the first time the successful use of the Hg1-xCdxTe native oxide as an encapsulation layer for an annealing process designed to activate an implanted impurity. The annealing process does not require Hg over pressure and consists of both furnace (∼200 °C) and rapid thermal (∼320 °C) anneals. Using 2.2 MeV 4He+ ion channeling measurements, we show that the implantation damage can be annealed out without loss of Hg from the substrate. Also, both secondary ion mass spectrometry and differential van der Pauw measurements indicate that the resulting electron concentration profile closely matches that of the implanted 11B profile and the electrical junction is found to lie close to the expected position of the metallurgical junction. [ABSTRACT FROM AUTHOR]
- Published
- 1986
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20. Intravenous Methamphetamine Does Not Appear to Be a Contraindication for Heart Donation in Heart Transplantation.
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Velleca, A., Kao, T., Kearney, B., Patel, J., Kittleson, M., Levine, R., Dimbil, S., Mersola, S., Hamilton, M., Esmailian, F., and Kobashigawa, J.
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HEART transplantation - Abstract
Purpose Intravenous methamphetamine (IV meth) use in potential heart donors has been of concern due to the possibility of methamphetamine cardiomyopathy and transmission of infections. There is also concern regarding the development of primary graft dysfunction (PGD) and cardiac allograft vasculopathy (CAV) due to possible endothelial cell dysfunction. Therefore, we reviewed our HTx data to identify those donors who primarily used IV meth in the past 6 months prior to organ donation. Methods Between 2010-2017 we identified 32 heart donors who were actively using IV meth. We compared this to 329 donors who had no history of drug use during the same time period. Endpoints included 1-year survival, 1-year freedom from CAV (as defined by stenosis ≥ 30% by angiography), non-fatal major adverse cardiac events (NF-MACE: myocardial infarction, new congestive heart failure, percutaneous coronary intervention, implantable cardioverter defibrillator/pacemaker implant, stroke), Any-Treated Rejection (ATR), Acute-Celular Rejection (ACR), Antibody-Mediated Rejection (AMR), and Biopsy-Negative Rejection (BNR). The incidence of PGD was also assessed. Results There was no significant difference in endpoints between IV meth use in donors and those donors without meth use (see table). The incidence of PGD was also not different between the groups. Other drugs that were being abused (in combination) included heroin at 46.8% and cocaine at 9.4%. The addition of these drugs did not change outcome. Conclusion The use of donors using IV meth does not appear to be a contraindication for HTx. Longer term follow up will be necessary to confirm these findings. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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21. Searching for high-k RE2O3 nanoparticles embedded in SiO2 glass matrix.
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Mukherjee, S., Lin, Y. H., Kao, T. H., Chou, C. C., and Yang, H. D.
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NANOPARTICLES , *RARE earth oxides , *SILICON oxide , *ANNEALING of metals , *PHYSICS - Abstract
Significant experimental effort has been explored to search and characterize high-k materials with magnetodielectric effect (MDE) of series of rare earth (RE) oxide (RE2O3) nanoparticles (NPs) embedded in SiO2 glass matrix by a sol-gel route. Properly annealed sol-gel glass (in which RE = Sm, Gd, and Er) shows colossal response of dielectric constant along with diffuse phase transition and MDE around room temperature. The radial distribution functions, reconstructed from extended x-ray absorption fine structure, show the shortening of RE3 + -O depending on the RE2O3 NP size, which is consistent with oxygen vacancy induced dielectric anomaly. The magnetoresistive MDE is very much conditioned by magnetic property of RE2O3 NP grain, the degree of deformation of the lattice and constituent host. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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22. Investigation of liver-targeted peripheral focused ultrasound stimulation (pFUS) and its effect on glucose homeostasis and insulin resistance in type 2 diabetes mellitus: a proof of concept, phase 1 trial.
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Ashe, J, Graf, J, Madhavan, R, Wallace, K, Cotero, V, Abate, S, Pandey, R K, Herzog, R, Porindla, S N, Shoudy, D, Fan, Y, Kao, T -J, and Puleo, C
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TYPE 2 diabetes , *INSULIN resistance , *ULTRASONIC imaging , *IMAGING systems , *WILCOXON signed-rank test , *VITAL signs - Abstract
Background Mechanical waves produced by ultrasound pulses have been shown to activate mechanosensitive ion channels and modulate peripheral nerves. However, while peripheral ultrasound neuromodulation has been demonstrated in vitro and in pre-clinical models, there have been few reports of clinical tests. Aim We modified a diagnostic imaging system for ultrasound neuromodulation in human subjects. We report the first safety and feasibility outcomes in subjects with type 2 diabetes (T2D) mellitus and discuss these outcomes in relation to previous pre-clinical results. Design The study was performed as an open label feasibility study to assess the effects of hepatic ultrasound (targeted to the porta hepatis) on glucometabolic parameters in subjects with T2D. Stimulation (peripheral focused ultrasound stimulation treatment) was performed for 3 days (i.e. 15 min per day), preceded by a baseline examination and followed by a 2-week observation period. Methods Multiple metabolic assays were employed including measures of fasting glucose and insulin, insulin resistance and glucose metabolism. The safety and tolerability were also assessed by monitoring adverse events, changes in vital signs, electrocardiogram parameters and clinical laboratory measures. Results and conclusion We report post-pFUS trends in several outcomes that were consistent with previous pre-clinical findings. Fasting insulin was lowered, resulting in a reduction of HOMA-IR scores (P -value 0.01; corrected Wilcoxon signed-rank test). Additional safety and exploratory markers demonstrated no device-related adverse impact of pFUS. Our findings demonstrate that pFUS represents a promising new treatment modality that could be used as a non-pharmaceutical adjunct or even alternative to current drug treatments in diabetes. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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23. (636) - Care After Heart Transplant, No One Better Than Family: Wrong.
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Stimpson, E., Kao, T., Kim, L., Morrison, S., Patel, J., Kittleson, M., Liou, F., Siddiqui, S., Yabuno, J., Czer, L., and Kobashigawa, J.A.
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HEART transplantation , *MEDICAL care , *CARDIAC surgery , *ARTIFICIAL implants , *MEDICAL research - Published
- 2015
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24. 59 Myth Buster: Does Homogeneous Racial Donor/Recipient Match Improve Outcome after Heart Transplantation?
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Kao, T., Velleca, A., Kittleson, M., Piponniau, L., Rush, J., Kawano, M., Goldstein, Z., Luthringer, D., Czer, L., Esmailian, F., and Kobashigawa, J.
- Published
- 2011
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25. Video-assisted thoracoscopic surgery in continuous ambulatory peritoneal dialysis-related hydrothorax.
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Lang, C.-L., Kao, T.-W., Lee, C.-M., Tsai, C.-W., and Wu, M.-S.
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KIDNEY diseases , *GENERAL practitioners , *OUTPATIENT medical care , *GASTROINTESTINAL diseases , *CHRONIC kidney failure , *RESPIRATORY diseases , *WOMEN'S health - Abstract
The article presents a case study of a 50-year-old lady with end-stage renal disease. The patient developed dyspnea, nausea, and vomiting soon after commencing continuous ambulatory peritoneal dialysis (CAPD). The chest X-ray did not show any recurrence of the pleural effusion up to 5 months later, while peritoneal scintigraphy and video-assisted thoracoscopic surgery with mesh repair provide a safe way to diagnose and treat CAPD-related hydrothorax.
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- 2008
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26. "Primary" benign retroperitoneal and intraspinal dumbbell-shaped cystic teratoma: case report.
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Kao T, Shen C, Chen C, Kwan P, Kao, Ting-Hsien, Shen, Chiung-Chyi, Chen, Chi-Chang, and Kwan, Pao-Hsiang
- Abstract
Study Design: A case of unusual dumbbell-shaped cystic teratoma is presented.Objectives: To investigate and describe an unusual case of retroperitoneal cystic teratoma with spinal invasion in an adult. The image findings, minimally invasive surgical procedures, and clinical outcome were discussed, and the literature was reviewed.Summary Of Background Data: Primary benign cystic teratomas of the retroperitoneum are rare. Extension of these lesions into the spinal canal is more rare. In this report, by presenting a case of cystic teratoma with such extension, the origin of the tumor, and the value of computerized tomography and magnetic resonance imaging (MRI) in the preoperative diagnosis and surgical approach for the extended lesion are discussed.Methods: The patient was a 24-year-old female who had had low back pain with bilateral sciatica for 2 months. Preoperative computerized tomography and MRI of the thoracic and lumbar spines showed a dumbbell-shaped tumor, with the solid part residing in the right retroperitoneum near the neuroforamen of the L2-L3 spines and the cystic part extending into the spinal canal. By performing right L2-L4 hemilaminectomies with a mini retroperitoneal approach, the tumor was removed en bloc in one stage.Results: Diagnosis of cystic teratoma was confirmed by pathologic examination. The patient recovered well without any neurologic deficits, and recurrence of tumor has not been found for 9 years postoperatively.Conclusions: Total surgical removal of tumor is an ideal treatment for retroperitoneal and intraspinal dumbbell-shaped cystic teratoma. MRI displays the precise location, morphology, and adjacent structures of the tumor, which provide for better preoperative planning and more complete removal of tumor with less neurologic damage. [ABSTRACT FROM AUTHOR]- Published
- 2005
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27. PERFORMANCE ENHANCEMENT OF InGaN-BASED LASER DIODES USING A STEP-GRADED AlxGa1-xN ELECTRON BLOCKING LAYER.
- Author
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ZHANG, Y., LIU, J.-P., KAO, T.-T., KIM, S., LEE, Y.-C., LOCHNER, Z., RYOU, J.-H., YODER, P. D., DUPUIS, R. D., and SHEN, S.-C.
- Subjects
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LIGHT emitting diodes , *PERFORMANCE evaluation , *OPTICAL polarization , *GALLIUM compounds , *QUANTUM theory , *ENERGY consumption , *MICROFABRICATION , *CURRENT density (Electromagnetism) - Abstract
A step-graded AlxGa1-xN electron blocking layer (EBL) is introduced to the InGaN-based edge-emitting blue-violet laser diode (LD) structure to suppress the undesired built-in interface polarization charges. When compared to a conventional abrupt Al0.18Ga0.82N EBL design, the step-graded AlxGa1-xN EBL design may help reduce the electron accumulation at the edge of the active region and hence improve the quantum efficiency in LD operation. The effects of the step-graded AlxGa1-xN EBL on the fabricated device performance are also investigated. LDs with the step-graded AlxGa1-xN EBL demonstrated significantly reduced threshold current density and increased slope efficiency under the continuous-wave operation. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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28. Post-tooth extraction sepsis without locoregional infection - a population-based study in Taiwan.
- Author
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Lee J, Hahn L, Kao T, Liu C, Cheng S, Chang H, Jeng J, and Kok S
- Abstract
Objective: To investigate the incidence and risk factors of post-tooth extraction sepsis in patients without locoregional infection. Subjects and Methods: We assessed all claim records of the Taiwanese National Health Insurance program in 2005. Admissions for patients aged >=16 years containing a discharge diagnosis of sepsis, and who received tooth extraction within 14 days before the admission were identified. Patient charts were reviewed to confirm the diagnosis of sepsis and rule out other infection sources. The relationship between postextraction sepsis (PES) and clinical parameters was analyzed. Results: Thirty-three of the 2 223 971 extraction cases met the criteria of PES, an incidence of 1.48 per 100 000, and seven patients (21.2%) died of the disease. Aging significantly increased the risk of PES ( P < 0.001). Pre-existing comorbidities were found in 20 of the 33 cases, with diabetes mellitus and hematologic diseases the most common. The method, number, and position of extraction had no influence on PES incidence. Blood cultures were positive in 25 patients (75.8%) and isolates included species of the Streptococcus, Actinomyces, Klebsiella, Bacteroides, Prevotella, and Enterococcus genera. Conclusion: Tooth extraction is associated with a low but significant risk of postoperative sepsis, especially in the elderly and patients with underlying diseases. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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29. Post-tooth extraction sepsis without locoregional infection – a population-based study in Taiwan.
- Author
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Lee, J‐J, Hahn, L‐J, Kao, T‐P, Liu, C‐H, Cheng, S‐J, Cheng, S‐L, Chang, H‐H, Jeng, J‐H, and Kok, S‐H
- Subjects
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DENTAL extraction complications , *SEPSIS , *NATIONAL health insurance , *DIABETES - Abstract
Objective: To investigate the incidence and risk factors of post-tooth extraction sepsis in patients without locoregional infection. Subjects and Methods: We assessed all claim records of the Taiwanese National Health Insurance program in 2005. Admissions for patients aged ≥16 years containing a discharge diagnosis of sepsis, and who received tooth extraction within 14 days before the admission were identified. Patient charts were reviewed to confirm the diagnosis of sepsis and rule out other infection sources. The relationship between postextraction sepsis (PES) and clinical parameters was analyzed. Results: Thirty-three of the 2 223 971 extraction cases met the criteria of PES, an incidence of 1.48 per 100 000, and seven patients (21.2%) died of the disease. Aging significantly increased the risk of PES ( P < 0.001). Pre-existing comorbidities were found in 20 of the 33 cases, with diabetes mellitus and hematologic diseases the most common. The method, number, and position of extraction had no influence on PES incidence. Blood cultures were positive in 25 patients (75.8%) and isolates included species of the Streptococcus, Actinomyces, Klebsiella, Bacteroides, Prevotella, and Enterococcus genera. Conclusion: Tooth extraction is associated with a low but significant risk of postoperative sepsis, especially in the elderly and patients with underlying diseases. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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30. Blood–brain barrier impairment with enhanced SP, NK-1R, GFAP and Claudin-5 expressions in experimental cerebral toxocariasis.
- Author
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LIAO, C.-W., CHO, W.-L., KAO, T.-C., SU, K.-E., LIN, Y.-H., and FAN, C.-K.
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TOXOCARA , *VISCERAL larva migrans , *NEUROGLIA , *NEUROPEPTIDES , *VASODILATION , *LABORATORY mice - Abstract
Infection by Toxocara canis in humans may cause cerebral toxocariasis (CT). Appreciable numbers of T. canis larvae cross the blood–brain barrier (BBB) to invade the brain thus causing CT. In the present studies, we evaluated the BBB permeability and BBB injury as assessed by the cerebral Evans blue (EB) concentration as well as by pathological changes and glial fibrillary acidic protein (GFAP) expression in T. canis -infected mice monitored from 3 days (dpi) to 8 weeks post-infection (wpi). The vasodilation neuropeptides, the expressions of substance P (SP) and its preferred binding neurokinin-1 receptor (NK-1R) as well as claudin-5 of tight-junction proteins associated with BBB impairment were also assessed by Western blotting and reverse-transcriptase polymerase chain reaction. Results revealed that BBB permeability increased as evidenced by a significantly elevated EB concentration in brains of infected mice. BBB injury appeared due to enhanced GFAP protein and mRNA expressions from 4 to 8 wpi. Leukocytes might have been unrelated to BBB impairment because there was no inflammatory cell infiltration despite T. canis larvae having invaded the brain; whereas markedly elevated SP protein and NK-1R mRNA expressions concomitant with enhanced claudin-5 expression seemed to be associated with persistent BBB impairment in this experimental CT model. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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31. Sero-epidemiology of Toxocara canis infection among aboriginal schoolchildren in the mountainous areas of north–eastern Taiwan.
- Author
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Fan, C.-K., Liao, C.-W., Kao, T.-C., Li, M.-H., Du, W.-Y., and Su, K.-E.
- Subjects
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TOXOCARA , *INDIGENOUS children , *EPIDEMIOLOGY , *ATAYAL (Taiwan people) - Abstract
A sero-epidemiological study of Toxocara canis infection was conducted among Atayal schoolchildren (aged 7–12 years) residing in the mountainous areas of north–eastern Taiwan. The 73 children investigated were each checked for anti-Toxocara IgG, in ELISA based on the larval excretory–secretory antigens of T. canis larvae. A short, self-administered questionnaire was then used to collect relevant information from each subject, including data on the keeping of dogs, playing in soil, eating raw vegetables, and whether the subjects normally washed their hands before eating. Once the seropositive children had been identified, odds ratios (OR), with their corresponding 95% confidence intervals (CI) and P-values, were calculated for each potential risk factor. When diluted 1:64, sera from 42 (57.5%) of the children gave a positive result in the ELISA, indicating that these 42 children were seropositive for T. canis infection. Seropositivity did not appear to be associated with the age or gender of the subject, the eating of raw vegetables, or the regular failure to wash hands prior to a meal. Compared with the other subjects, however, those who admitted living in a household where dogs were kept (OR = 3.79; CI = 1.23–11.69; P=0.02) or playing in soil (OR = 3.00; CI = 1.10–8.16; P=0.03) appeared at increased risk of seropositivity. [ABSTRACT FROM AUTHOR]
- Published
- 2005
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32. Preoperative and operative factors to predict incontinence, impotence and stricture after radical prostatectomy.
- Author
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Moul, J W, Mooneyhan, R M, Kao, T-C, McLeod, D G, and Cruess, D F
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PROSTATECTOMY , *URINARY incontinence , *IMPOTENCE , *PROSTATE cancer - Abstract
The purpose of this study was to determine the incidence of patient-self reported post prostatectomy incontinence, impotence, bladder neck contracture or stricture, better, same or worse quality of life and willingness for same treatment again in a large group of radical prostatectomy (RP) patients and to determine if these morbidities are predictable with demographic, surgical or prostate cancer (PC) factors. Methods: A patient self-reporting questionnaire was completed and returned by 374 out of 458 eligible (81.7%) RP patients from one center, 267 (72.2%) have been operated since 1990 and all of whom were a minimum six month postoperative (75%>1 y). Questionnaire results were independently analyzed by a third party and correlated to demographic, operative, and tumor factors in an ongoing comprehensive PC database. Results: The patient self-reported incidence of post prostatectomy incontinence (any degree), impotence, and bladder neck contracture or stricture was 72.2, 87.4, and 25.9%, respectively. The reported rate of incontinence requiring protection was 39.0% and only 2.4% had persistent bladder neck contracture/stricture. Pathologic stage (continuous variable) was the only factor to significantly predict incontinence and no factor could predict impotence or bladder neck contracture/stricture in univariate analysis. No factor was predictive of morbidity by multivariate analysis. Despite incontinence and impotence significantly affecting QOL self-reporting (P=0.001, 0.001, respectively) and willingness to undergo RP again (P=0.001, 0.067, respectively), the majority of patients would choose surgery again. Conclusions: Although radical prostatectomy morbidity is common and affects patient-reported overall QOL, most patients would choose the same treatment again. Demographic, preoperative, operative, and tumor factors did not reliably predict patient-reported morbidity in this series. [ABSTRACT FROM AUTHOR]
- Published
- 1998
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33. Proposed Algorithm Aids Assessment of COVID Positive Donors in Thoracic Organ Transplant.
- Author
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Velleca, A., Zakowski, P., Berliner, H., Kao, T., May, B., Kobashigawa, J., Rampolla, R., Esmailian, F., and Megna, D.
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TRANSPLANTATION of organs, tissues, etc. , *COVID-19 , *ORGAN donors , *HEART transplant recipients , *HEART transplantation , *HOMOGRAFTS - Abstract
An algorithm was developed to assess COVID-positive donors. To assess effectiveness of this screening process, we reviewed our single center experience in both heart and lung transplant recipients. We reviewed 13 heart transplant (HT) and 9 lung transplant (LT) recipients who received an organ from a COVID-positive donor between 2/21 and 8/22 and were followed for 90 days. An algorithm consisting of 4 clinical scenarios was developed to aid donor offer review (see figure). COVID PCR testing was performed by nasopharyngeal swab. BAL specimen was required for lung donors. Donors with COVID PCR CT < 25 were declined, CT of 25-35 required joint clinical interpretation with transplant infectious disease, and CT > 35 were considered for transplant. Endpoints: COVID infection by 30 days, survival at 90 days, non-fatal major adverse cardiac events (NF-MACE; myocardial infarction, heart failure, percutaneous intervention, stroke) within 90 days for HT, rejection at 90 days, and severe PGD. All COVID-positive HT donors were scenario 3. No recipient and no staff involved in procurement acquired COVID 19 infection post-HT. Within 90 days post-HT, no patient experienced NF-MACE, 1 patient developed pAMR 2, 2 patients experienced severe PGD requiring VA-ECMO, and 1 patient experienced profound bleeding requiring VA ECMO and died 5 months post-HT of pulmonary embolism. For LT recipients, COVID-positive donors were scenario 1 (1), scenario 2(2) and scenario 3(6). All recipients received bilateral LT and no deaths occurred. Within 30 days post-LT, no patient or staff developed COVID infection, 2 recipients developed PGD (3 needing re-intubation), and 2 patients with A1 cellular rejection. No strokes were observed. Utilizing our program's COVID-19 donor algorithm, the use of heart and lung COVID-19 positive donors appears safe. Transplantation of thoracic organs is possible in COVID-19 positive donors with low titer, non-COVID related cause of death and no COVID related clinical complications. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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34. (377) - Care Giver Support for Heart Transplant: Does the Type of Provider Matter?
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Stimpson, E., Velleca, A., Kao, T., Kim, L., Kittleson, M., Patel, J., Czer, L., Chang, D., Hamilton, M., Ramzy, D., and Kobashigawa, J.A.
- Subjects
- *
HEART transplant recipients , *HEART transplantation -- Social aspects , *CARDIAC surgery , *GRAFT rejection , *HEALTH programs , *SOCIAL support , *HEALTH outcome assessment , *THERAPEUTICS - Published
- 2016
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35. Validation of liquid chromatography–tandem mass spectrometry method for urinary cortisol
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Li, D., White, A., Kao, T., and Pudek, M.
- Published
- 2008
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36. Frequency Locking and Monitoring Based on Bi-directional Terahertz Radiation of a 3-Order Distributed Feedback Quantum Cascade Laser.
- Author
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van Marrewijk, N., Mirzaei, B., Hayton, D., Gao, J., Kao, T., Hu, Q., and Reno, J.
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- *
SUBMILLIMETER waves , *BISMUTH , *QUANTUM cascade lasers , *DISTRIBUTED computing , *FEEDBACK control systems - Abstract
We have performed frequency locking of a dual, forward reverse emitting third-order distributed feedback quantum cascade laser (QCL) at 3.5 THz. By using both directions of THz emission in combination with two gas cells and two power detectors, we can for the first time perform frequency stabilization, while monitor the frequency locking quality independently. We also characterize how the use of a less sensitive pyroelectric detector can influence the quality of frequency locking, illustrating experimentally that the sensitivity of the detectors is crucial. Using both directions of terahertz (THz) radiation has a particular advantage for the application of a QCL as a local oscillator, where radiation from one side can be used for frequency/phase stabilization, leaving the other side to be fully utilized as a local oscillator to pump a mixer. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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37. When is Significant Left Ventricular Hypertrophy Acceptable for Donor Heart Selection.
- Author
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Patel, J., Kittleson, M., Kransdorf, E., Patel, N., Singer-Englar, T., Kao, T., Hage, A., Czer, L., Esmailian, F., and Kobashigawa, J.A.
- Subjects
- *
LEFT ventricular hypertrophy , *HEART transplantation , *HEART , *OLD age - Abstract
Extended criteria of donors for heart transplant (HTx) include many factors, such as left ventricular hypertrophy (LVH), decreased LVEF, older donor age, inotrope dependence, as well as gender and size mismatch. It has also been reported that various combinations of extended criteria risk factors appear to have worse outcomes depending on severity of the extended criteria characteristic. We sought to assess if severity of LVH with acceptable donor age and ischemic time is associated with increased mortality. Between 2010 and 2020, we assessed 156 donor hearts with varying degrees of LVH defined as left ventricular septal thickness greater than 1.2 cm. Donor hearts were then divided into those that had IVS between 1.2 to <1.3 cm, 1.3 to <1.5 cm, ≥1.5 cm. In addition, an assessment was made for the same LVH groups versus donor age categorized as donor age ≥50 years old and donor ischemic time >240minutes. Severity of LVH with donor age <50 years and ischemic time <240 min appear to have acceptable 1-year survival. However, older donor age/long ischemic time with LVH are higher risk for 1-year mortality. (see table) Severe LVH (IVS >1.5 cm) in donor hearts appears to be acceptable with donor age <50 years and ischemic time <240 minutes. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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38. Phase locking of a 3.4 THz third-order distributed feedback quantum cascade laser using a room-temperature superlattice harmonic mixer.
- Author
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Hayton, D. J., Khudchencko, A., Pavelyev, D. G., Hovenier, J. N., Baryshev, A., Gao, J. R., Kao, T. Y., Hu, Q., Reno, J. L., and Vaks, V.
- Subjects
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QUANTUM cascade lasers , *SUPERLATTICES , *SIGNAL-to-noise ratio , *ELECTRICAL harmonics , *DISTRIBUTED feedback lasers - Abstract
We report on the phase locking of a 3.4 THz third-order distributed feedback quantum cascade laser (QCL) using a room temperature GaAs/AlAs superlattice diode as both a frequency multiplier and an internal harmonic mixer. A signal-to-noise level of 60 dB is observed in the intermediate frequency signal between the 18th harmonic of a 190.7 GHz reference source and the 3433 GHz QCL. A phase-lock loop with 7 MHz bandwidth results in QCL emission that is 96% locked to the reference source. We characterize the QCL temperature and electrical tuning mechanisms and show that frequency dependence of these mechanisms can prevent phase-locking under certain QCL bias conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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39. Beam and phase distributions of a terahertz quantum cascade wire laser.
- Author
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Cui, M., Hovenier, J. N., Ren, Y., Vercruyssen, N., Gao, J. R., Kao, T. Y., Hu, Q., and Reno, J. L.
- Subjects
- *
QUANTUM cascade lasers , *ELECTRIC fields , *ANTENNA arrays , *LASERS , *SEMICONDUCTOR lasers - Abstract
We report on both measurements and simulations of the beam profile and wavefront of a single-mode, 3.5 THz quantum cascade wire laser, incorporating a lateral corrugated metal-metal waveguide, 3rd-order distributed feedback grating. The intrinsic wavefront was measured by using a Hartmann wavefront sensor (HWS) without any optical components between the laser and HWS. Both beam profile and wavefront were simulated using an antenna array model, but taking the non-uniform electric field distribution along the waveguide into account. The results show that the non-uniform distribution along the wire laser plays a crucial role in realizing a nearly single-lobed narrow beam. The measured wavefront is spherical and agrees well with the simulation. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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40. Frequency locking of single-mode 3.5-THz quantum cascade lasers using a gas cell.
- Author
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Ren, Y., Hovenier, J. N., Cui, M., Hayton, D. J., Gao, J. R., Klapwijk, T. M., Shi, S. C., Kao, T.-Y., Hu, Q., and Reno, J. L.
- Subjects
- *
PHYSICS research , *QUANTUM cascade lasers , *LASER research , *ABSORPTION , *MOLECULAR spectroscopy , *NONLINEAR optics , *SPECTRAL energy distribution - Abstract
We report frequency locking of two 3.5-THz third-order distributed feedback (DFB) quantum cascade lasers (QCLs) by using methanol molecular absorption lines, a proportional-integral-derivative controller, and a NbN bolometer. We show that the free-running linewidths of the QCLs are dependent on the electrical and temperature tuning coefficients. For both lasers, the frequency locking induces a similar linewidth reduction factor, whereby the narrowest locked linewidth is below 18 kHz with a Gaussian-like shape. The linewidth reduction factor and the ultimate linewidth correspond to the measured frequency noise power spectral density. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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41. Probing Alzheimer's Disease Pathology and Early Detection at the NSLS with Infrared, XRF, and DEI.
- Author
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Zhong, Z., Bennett, D., Chapman, D., Chen, J., Connor, D., Dilmanian, A., Faulconer, L., Kao, T., Leskovjan, A. C., Li, J., Liu, T., Miller, L. M., Muehleman, C., Parham, C., Pisano, E., and Wu, A.
- Subjects
- *
PATHOLOGY education , *ALZHEIMER'S disease , *TOMOGRAPHY , *AMYLOID , *AMYLOID beta-protein , *SYNCHROTRON radiation , *FLUORESCENCE microscopy - Abstract
We explored diffraction enhanced imaging (DEI) in both planar and computed tomography (CT) modes for early detection of beta amyloid deposition, a hallmark feature in Alzheimer's disease (AD). Since amyloid plaques precede clinical symptoms by years, their early detection is of great interest. These findings were correlated with results from synchrotron infrared microspectroscopic imaging and X-ray fluorescence microscopy, to determine the secondary structure of the amyloid beta protein and metal concentration in the amyloid plaques, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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42. Administration of 5-androstenediol to mice: Pharmacokinetics and cytokine gene expression
- Author
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Singh, V.K., Grace, M.B., Jacobsen, K.O., Chang, C-M., Parekh, V.I., Inal, C.E., Shafran, R.L., Whitnall, A.D., Kao, T-C., Jackson, W.E., and Whitnall, M.H.
- Subjects
- *
RADIATION , *CELLULAR immunity , *IRRADIATION , *CHEMICAL kinetics - Abstract
Abstract: The development of an effective pharmacological countermeasure is needed to reduce the morbidity and mortality in military and civilian populations associated with possible exposure to ionizing radiation. Previous studies in mice have shown that a single subcutaneous (sc) injection of the natural steroid androst-5-ene-3β,17β-diol (5-androstenediol, 5-AED), 24–48 h prior to a lethal dose of whole-body 60Co gamma radiation, stimulated hematopoiesis and enhanced survival. These effects are consistent with our previous observation of 5-AED-induced elevations in circulating G-CSF in normal and irradiated mice. The purpose of this study was to obtain data on the pharmacokinetics of 5-AED after sc and buccal administration to mice, and to determine whether cytokine genes are induced by sc 5-AED in hematopoietic tissues (bone marrow, spleen). We studied effects on serum cytokines and chemokines, and also analyzed the pharmacokinetics of 5-AED after sc administration and compared it with buccal delivery. 5-AED was administered 24 h before irradiation or sham-irradiation. Cytokine mRNAs were quantified by quantitative real-time PCR (QRT-PCR), and cytokine levels in serum by multiplex Luminex. 5-AED administration was associated with elevation of message for GM-CSF, IL-2, IL-3, IL-6, and IL-10 in spleen, and GM-CSF and IL-2 in bone marrow. Irradiation enhanced G-CSF, GM-CSF, IFN-γ, TPO, IL-2, IL-3, IL-6, IL-10, and IL-12 in spleen, and GM-CSF, IFN-γ, TPO, IL-3, and IL-10 in bone marrow. Serum levels of G-CSF were significantly elevated in 5-AED-treated mice 4 h after irradiation or sham-irradiation. Serum macrophage inflammatory protein-1γ (MIP-1γ) was significantly elevated 4 h after irradiation in 5-AED-treated mice. Plasma 5-AED peaked 2 h after sc injection (30 mg/kg), and remained significantly above control after 4 days, but not 8 days. The time course of plasma 5-AED after buccal delivery (60 mg/kg) was similar, but levels were significantly lower compared to sc delivery. Plasma 5-AED 24 h after administration was not significantly different between sc and buccal delivery. However, in contrast to many studies showing enhanced survival after sc administration of 5-AED, we found no effect on survival of buccal 5-AED. The results suggest that radioprotection is not dependent on the 5-AED concentration at the time of irradiation, but rather on events triggered during the first few hours after administration. The current results suggest that further studies are warranted to directly test the roles of cytokines in the radioprotective effects of 5-AED. [Copyright &y& Elsevier]
- Published
- 2008
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43. KCNQ channels mediate IKs, a slow K+ current regulating excitability in the rat node of Ranvier.
- Author
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Schwarz, J. R., Glassmeier, G., Cooper, E. C., Kao, T.-C., Nodera, H., Tabuena, D., Kaji, R., and Bostock, H.
- Subjects
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ION channels , *NODES of Ranvier , *NERVES , *IMMUNOCYTOCHEMISTRY , *RATS - Abstract
Mutations that reduce the function of KCNQ2 channels cause neuronal hyperexcitability, manifested as epileptic seizures and myokymia. These channels are present in nodes of Ranvier in rat brain and nerve and have been proposed to mediate the slow nodal potassium current IKs. We have used immunocytochemistry, electrophysiology and pharmacology to test this hypothesis and to determine the contribution of KCNQ channels to nerve excitability in the rat. When myelinated nerve fibres of the sciatic nerve were examined by immunofluorescence microscopy using antibodies against KCNQ2 and KCNQ3, all nodes showed strong immunoreactivity for KCNQ2. The nodes of about half the small and intermediate sized fibres showed labelling for both KCNQ2 and KCNQ3, but nodes of large fibres were labelled by KCNQ2 antibodies only. In voltage-clamp experiments using large myelinated fibres, the selective KCNQ channel blockers XE991 and linopirdine completely inhibited IKs, as did TEA . The KCNQ channel opener retigabine (10 μm) shifted the activation curve to more negative membrane potentials by −24 mV, thereby increasing IKs. In isotonic KCl 50% of IKs was activated at −62 mV. The activation curve shifted to more positive potentials as [K+]o was reduced, so that the pharmacological and biophysical properties of IKs were consistent with those of heterologously expressed homomeric KCNQ2 channels. The ability of XE991 to selectively block IKs was further exploited to study IKs function in vivo. In anaesthetized rats, the excitability of tail motor axons was indicated by the stimulus current required to elicit a 40% of maximal compound muscle action potential. XE991 (2.5 mg kg−1i.p.) eliminated all nerve excitability functions previously attributed to IKs: accommodation to 100 ms subthreshold depolarizing currents, the post-depolarization undershoot in excitability, and the late subexcitability after a single impulse or short trains of impulses. Due to reduced spike-frequency adaptation after XE991 treatment, 100 ms suprathreshold current injections generated long trains of action potentials. We conclude that the nodal IKs current is mediated by KCNQ channels, which in large fibres of rat sciatic nerve appear to be KCNQ2 homomers. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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44. Late-presenting appendicitis: a laparoscopic approach to a complicated problem.
- Author
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Gibeily, G J, Ross, M N, Manning, D B, Wherry, D C, and Kao, T-C
- Subjects
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APPENDICITIS treatment , *APPENDECTOMY , *APPENDICITIS , *CHRONIC diseases , *COMPARATIVE studies , *LENGTH of stay in hospitals , *LAPAROSCOPY , *RESEARCH methodology , *MEDICAL cooperation , *RESEARCH , *SURGICAL complications , *TIME , *EVALUATION research , *CECUM , *RETROSPECTIVE studies , *ACUTE diseases , *DIAGNOSIS , *TUMORS - Abstract
Background: Acute appendicitis is the most common abdominal condition necessitating urgent surgical intervention in the United States. The objective of this study was to determine if interval laparoscopic appendectomy after initial nonoperative treatment for late appendicitis presenting as an appendiceal mass is a safe alternative to immediate appendectomy.Methods: Thirty two consecutive patients (aged 16-74 years) during a 5-year period presented with appendiceal mass. Seventeen received initial nonsurgical treatment followed by interval laparoscopic appendectomy (aged 16-60 years; group 1). Fifteen underwent immediate appendectomy (aged 16-74 years; group 2).Results: All patients in the interval laparoscopic appendectomy group improved with initial therapy and underwent surgery an average of 4.9 months later. Although the operative time and the complication rate were similar between groups 1 and 2, the time to return to baseline activities was significantly less in group 1 after adjusting for age (p = 0.02 or less).Conclusions: Interval laparoscopic appendectomy is safe in patients with chronic appendicitis and allows for judicious diagnostic evaluation of the appendiceal mass and planned surgery under controlled conditions. [ABSTRACT FROM AUTHOR]- Published
- 2003
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- View/download PDF
45. Late-presenting appendicitis.
- Author
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Gibeily, G. J., Ross, M. N., Manning, D. B., Wherry, D. C., and Kao, T.- C.
- Subjects
- *
APPENDECTOMY , *LAPAROSCOPIC surgery , *APPENDICITIS treatment , *APPENDIX surgery , *ENDOSCOPIC surgery - Abstract
Background: Acute appendicitis is the most common abdominal condition necessitating urgent surgical intervention in the United States. The objective of this study was to determine if interval laparoscopic appendectomy after initial nonoperative treatment for late appendicitis presenting as an appendiceal mass is a safe alternative to immediate appendectomy. Methods: Thirty two consecutive patients (aged 16–74 years) during a 5-year period presented with appendiceal mass. Seventeen received initial nonsurgical treatment followed by interval laparoscopic appendectomy (aged 16–60 years; group 1). Fifteen underwent immediate appendectomy (aged 16–74 years; group 2). Results: All patients in the interval laparoscopic appendectomy group improved with initial therapy and underwent surgery an average of 4.9 months later. Although the operative time and the complication rate were similar between groups 1 and 2, the time to return to baseline activities was significantly less in group 1 after adjusting for age (p = 0.02 or less). Conclusions: Interval laparoscopic appendectomy is safe in patients with chronic appendicitis and allows for judicious diagnostic evaluation of the appendiceal mass and planned surgery under controlled conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2003
- Full Text
- View/download PDF
46. Late-presenting appendicitis.
- Author
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Gibeily, G. J., Ross, M. N., Manning, D. B., Wherry, D. C., and Kao, T. -C.
- Subjects
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APPENDECTOMY , *APPENDICITIS treatment , *LAPAROSCOPIC surgery , *APPENDIX surgery , *ENDOSCOPIC surgery - Abstract
Background: Acute appendicitis is the most common abdominal condition necessitating urgent surgical intervention in the United States. The objective of this study was to determine if interval laparoscopic appendectomy after initial nonoperative treatment for late appendicitis presenting as an appendiceal mass is a safe alternative to immediate appendectomy. Methods: Thirty two consecutive patients (aged 16–74 years) during a 5-year period presented with appendiceal mass. Seventeen received initial nonsurgical treatment followed by interval laparoscopic appendectomy (aged 16–60 years; group 1). Fifteen underwent immediate appendectomy (aged 16–74 years; group 2). Results: All patients in the interval laparoscopic appendectomy group improved with initial therapy and underwent surgery an average of 4.9 months later. Although the operative time and the complication rate were similar between groups 1 and 2, the time to return to baseline activities was significantly less in group 1 after adjusting for age (p = 0.02 or less). Conclusions: Interval laparoscopic appendectomy is safe in patients with chronic appendicitis and allows for judicious diagnostic evaluation of the appendiceal mass and planned surgery under controlled conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2003
- Full Text
- View/download PDF
47. Implementation of a short-tip tapping-mode tuning fork near-field scanning optical microscope.
- Author
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Lu, N. H., Huang, C. W., Chen, C. Y., Yu, C. F., Kao, T. S., Fu, Y. H., and Tsai, D. P.
- Subjects
- *
NEAR-field microscopy , *TUNING forks , *PIEZOELECTRICITY - Abstract
Summary We present the implementation of a short-tip tapping-mode tuning fork near-field scanning optical microscope. Tapping frequency dependences of the piezoelectric signal amplitudes for a bare tuning fork fixed on the ceramic plate, a short-tip tapping-mode tuning fork scheme and an ordinary tapping-mode tuning fork configuration with an 80-cm optical fibre attached are demonstrated and compared. Our experimental results show that this new short-tip tapping-mode tuning fork scheme provides a stable and high Q factor at the tapping frequency of the tuning fork and will be very helpful when long optical fibre probes have to be used in an experiment. Both collection and excitation modes of short-tip tapping-mode tuning fork near-field scanning optical microscope are applied to study the near-field optical properties of a single-mode telecommunication optical fibre and a green InGaN/GaN multiquantum well light-emitting diode. [ABSTRACT FROM AUTHOR]
- Published
- 2003
- Full Text
- View/download PDF
48. The relative incidence of anterior cruciate ligament injury in men and women at the United States Naval Academy.
- Author
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Gwinn DE, Wilckens JH, McDevitt ER, Ross G, and Kao T
- Abstract
The purpose of this study was to evaluate the relative risk of anterior cruciate ligament injury in female versus male midshipmen at the United States Naval Academy. From 1991 to 1997, we recorded the incidence of anterior cruciate ligament injury during intercollegiate athletics, intramural athletics, and military training. The subjects were male and female varsity athletes, coed intramural athletes, and participants in military training consisting of the obstacle course and instructional wrestling. All patient data were collected at the time of injury. Records filed at the intramural sports office, along with a questionnaire completed by coaches and trainers, were used to estimate midshipmen exposures. Results showed that in intercollegiate soccer, basketball, and rugby, women had a relative injury risk of 3.96 compared with men. In coed soccer, basketball, softball, and volleyball, the women's relative injury risk was 1.40 compared with men. In military training, women had a relative injury risk of 9.74 compared with men. In comparing overall annual anterior cruciate ligament injury rates among midshipmen, we found that women had a relative injury risk of 2.44 compared with men. We concluded that female midshipmen have an increased relative risk of anterior cruciate ligament injury as compared with men in intercollegiate athletics, basic military training, and throughout their service academy career. This increase was not statistically significant at the intramural level of athletics. [ABSTRACT FROM AUTHOR]
- Published
- 2000
- Full Text
- View/download PDF
49. High-resolution heterodyne spectroscopy using a tunable quantum cascade laser around 3.5 THz.
- Author
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Ren, Y., Hovenier, J. N., Higgins, R., Gao, J. R., Klapwijk, T. M., Shi, S. C., Klein, B., Kao, T.-Y., Hu, Q., and Reno, J. L.
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HETERODYNE reception , *QUANTUM theory , *CASCADES (Fluid dynamics) , *METHANOL , *MOLECULAR spectra - Abstract
A frequency tunable terahertz heterodyne spectrometer, based on a third-order distributed feedback quantum cascade laser as a local oscillator, has been demonstrated by measuring molecular spectral lines of methanol (CH3OH) gas at 3.5 THz. By varying the bias voltage of the laser, we achieved a tuning range of ∼1 GHz of the lasing frequency, within which the molecular spectral lines were recorded. The measured spectra show excellent agreement with modeled ones. By fitting we derived the lasing frequency for each bias voltage accurately. The ultimate performance of the receiver including the resolution of noise temperature and frequency is also addressed. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
50. Fabrication and performance of blue GaN-based vertical-cavity surface emitting laser employing AlN/GaN and Ta2O5/SiO2 distributed Bragg reflector.
- Author
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Chih-Chiang Kao, Peng, Y. C., Yao, H. H., Tsai, J. Y., Chang, Y. H., Chu, J. T., Huang, H. W., Kao, T. T., Lu, T. C., Kuo, H. C., Wang, S. C., and Lin, C. F.
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DIELECTRICS , *LASERS , *DIELECTRIC devices , *LASER beams , *OPTICS , *POLARIZATION (Electricity) - Abstract
GaN-based vertical-cavity surface emitting laser with 3 λ cavity and hybrid mirrors, consisting of the 25 pairs AlN/GaN dielectric Bragg reflector and the 8 pairs Ta2O5/SiO2, was fabricated. The laser action was achieved under the optical pumping at room temperature with a threshold pumping energy density of about 53 mJ/cm2. The laser emits 448 nm blue wavelength with a linewidth of 0.25 nm and the laser beam has a degree of polarization of about 84%. [ABSTRACT FROM AUTHOR]
- Published
- 2005
- Full Text
- View/download PDF
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