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Yuan CS, Chiang KC, Yen PH, Ceng JH, Lee CE, Du IC, Soong KY, Jeng MS. Long-range transport of atmospheric speciated mercury from the eastern waters of Taiwan Island to northern South China Sea. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 318:120899. [PMID: 36565910 DOI: 10.1016/j.envpol.2022.120899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 12/01/2022] [Accepted: 12/16/2022] [Indexed: 06/17/2023]
Abstract
This study explored the temporospatial distribution, gas-particle partition, and pollution sources of atmospheric speciated mercury (ASM) from the eastern offshore waters of the Taiwan Island (TI) to the northern South China Sea (SCS). Both gaseous and particulate mercury were simultaneously sampled at three remote sites in four seasons. The average concentrations of gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM), and particulate bound mercury (PBM) were 2.05 ± 0.45 ng/m3, 19.17 ± 5.39 pg/m3, and 0.11 ± 0.06 ng/m3, respectively. The concentrations of GEM and PBM in the cold seasons were higher than those in the warm seasons, but those of GOM had an opposite trend. In terms of gas-solid partition, ASM was apportioned as 91.3-97.3% of GEM and 2.7-8.7% of GOM and PBM. The average concentrations of GEM, GOM, and PBM at the Green Island (GI) were 2.21 ± 0.47 ng/m3, 22.31 ± 5.35 pg/m3, and 0.12 ± 0.06 ng/m3; those at the Kenting Peninsula (KT) were 2.11 ± 0.43 ng/m3, 20.57 ± 4.38 pg/m3, and 0.11 ± 0.06 ng/m3; and those at the Dongsha Islands (DS) were 1.84 ± 0.40 ng/m3, 15.19 ± 3.58 pg/m3, and 0.08 ± 0.05 ng/m3, respectively. Overall, the spatial distribution of ASM concentrations showed the order as: GI > KT > DS. Air masses blown mainly from the West Pacific Ocean (WPO) and SCS in summer showed the lowest ASM concentrations. Oppositely, high ASM concentrations were commonly observed in spring and winter when polluted air masses were blown by Asian Northeastern Monsoons (ANMs). The transport routes of polluted air masses were originated mainly from North China, Central China, Northeast China, Korea and Japan, and mostly passed through the urban and industrial regions in the northeastern Asian countries.
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Yuan CS, Lee CE, Ie IR, Chiang KC, Tseng YL, Wong KW. Seasonal variation and source identification of atmospheric speciated mercury in an industrial harbor area in East Asia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 815:152785. [PMID: 34990687 DOI: 10.1016/j.scitotenv.2021.152785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Revised: 12/23/2021] [Accepted: 12/26/2021] [Indexed: 06/14/2023]
Abstract
In this study, the pollution characteristics, spatiotemporal variation, and potential sources of atmospheric speciated mercury (ASM) in an industrial harbor area were explored. Gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM), and particle-bound mercury (PBM) were sampled by a self-designed manual system at three harbor sites in four seasons. The yearly average concentrations of GEM, GOM, and PBM were 6.7 ± 2.0 ng/m3, 244 ± 70 pg/m3, and 410 ± 105 pg/m3, respectively. The seasonal average ASM concentration was in the order of: winter > fall > spring > summer. In terms of species, GEM dominated ASM, while reactive mercury (RM = GOM + PBM) accounted for 6.0-15.7%of ASM, implying that ASM was governed by anthropogenic sources in the harbor area. The highest ASM concentrations were observed at Site Zhonghe (ZH), which is mainly influenced by both ship exhausts and industrial emissions, and positively correlated with CO, NOx, and SO2. In particular, GOM was positively correlated with O3, and negatively correlated with air temperature and relative humidity, showing high impact from atmospheric photochemical reactions. Air masses transporting westerly in spring were mainly from ship exhausts. In summer, air masses transporting from the south were from utility power plants and machinery exhausts. In fall and winter, air masses were transported mainly from the north, blowing by the long-range transport of polluted air masses originated from the north. Both principal component analysis and positive matrix factorization results indicate that coal burning, industrial emissions, and vehicular exhausts are the main contributors to ASM. Site Zhongdao (ZD) was close to the bulk carrier loading and unloading zones and was highly influenced by mobile sources, while Site ZH was mainly influenced by the neighboring industrial complex.
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Chen PY, Hsu CY, Lee CE, Chang IF. Arabidopsis glutamate receptor GLR3.7 is involved in abscisic acid response. PLANT SIGNALING & BEHAVIOR 2021; 16:1997513. [PMID: 34763610 PMCID: PMC9208785 DOI: 10.1080/15592324.2021.1997513] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The ionotropic glutamate receptor (iGluR) plays an important role in neuronal signaling in animal cells. There are at least 20 glutamate receptor-like (GLR) genes in Arabidopsis thaliana. These genes are involved in seed germination, root growth, wounding response, stomata closure, etc. A recent study showed that Arabidopsis clade III glutamate receptor GLR3.7 is involved in salt stress response. We tested whether GLR3.7 is involved in abscisic acid (ABA) response. In the present study, we found that the expression of GLR3.7 was reduced by ABA treatment. Under ABA-treated condition, GLR3.7 overexpression lines exhibited significantly higher seed germination rate at 60, 72 and 84 h under ABA-treated condition. A point mutation in 14-3-3 binding site of GLR3.7 in GLR3.7-S860A overexpression lines exhibited higher seed germination inhibition under ABA-treated conditions. Our results support that GLR3.7 is involved in ABA response in Arabidopsis. In addition, Ser-860 of GLR3.7 appears to be important in ABA response.
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Lan SM, Lin JY, Su ZX, Hsu HW, Lee CE, Hsu MP. [Improve the Integrity Rate of Response and Teaching for Tube Care Administered by the Primary Caregiver]. HU LI ZA ZHI THE JOURNAL OF NURSING 2021; 68:73-80. [PMID: 34013508 DOI: 10.6224/jn.202106_68(3).10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND & PROBLEM The need to use an indwelling nasogastric tube, urinary catheter, or tracheostomy tube (the so-called "three tubes") because of illness or prolonged bedrest is increasing. The functions and effectiveness of these tubes may be maintained only with correct care. Improper care, slippage, obstruction, or infection may in severe cases cause septic shock or even death. PURPOSE To increase the completeness of the reverse demonstration of three tubes care instructions by primary caregivers to further improve related care quality. RESOLUTION Between February 10th and March 31st, 2019, the completeness rates of reverse demonstration of nasogastric tube, urinary catheter, and tracheostomy tube care instructions among the primary caregivers participating in this study were shown to be low, at 42.5%, 38%, and 58.3%, respectively. The plausible causes were: 1. Human: Poor communication, forgetting the care steps, having no time for learning, and fear of performing nasogastric tube rotation; 2. Instrument: Lack of graphic demonstrations in health education materials; 3. Policy: Lack of standards and auditing. The implemented intervention involved creating innovative health-education instruments, videos and flash cards about three tubes care in multiple languages, and straps for holding the urinary catheter and developing standards and an auditing system for the reverse demonstration of three tube care instructions by primary caregivers. RESULTS The completeness rates for the reverse demonstration of nasogastric tube, urinary catheter, and tracheostomy tube care instructions among the primary caregivers improved to 97.3%, 96.3%, and 95%, respectively. CONCLUSIONS Using the innovative health-education aids and improvements introduced in this study, the ability of primary caregivers to correctly perform the care steps should improve significantly.
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Tan WPM, Sayampanathan AA, Tan TC, Tan CPF, Lee CE, Tan HCA, Tay KS. Rapid deployment of a telemedicine service in orthopaedic surgery during the COVID-19 pandemic. Singapore Med J 2020; 63:621-627. [DOI: 10.11622/smedj.2020156] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Zhang X, Lee CE, Shao X. Envelopes in multivariate regression models with nonlinearity and heteroscedasticity. Biometrika 2020. [DOI: 10.1093/biomet/asaa036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Summary
Envelopes have been proposed in recent years as a nascent methodology for sufficient dimension reduction and efficient parameter estimation in multivariate linear models. We extend the classical definition of envelopes in Cook et al. (2010) to incorporate a nonlinear conditional mean function and a heteroscedastic error. Given any two random vectors ${X}\in\mathbb{R}^{p}$ and ${Y}\in\mathbb{R}^{r}$, we propose two new model-free envelopes, called the martingale difference divergence envelope and the central mean envelope, and study their relationships to the standard envelope in the context of response reduction in multivariate linear models. The martingale difference divergence envelope effectively captures the nonlinearity in the conditional mean without imposing any parametric structure or requiring any tuning in estimation. Heteroscedasticity, or nonconstant conditional covariance of ${Y}\mid{X}$, is further detected by the central mean envelope based on a slicing scheme for the data. We reveal the nested structure of different envelopes: (i) the central mean envelope contains the martingale difference divergence envelope, with equality when ${Y}\mid{X}$ has a constant conditional covariance; and (ii) the martingale difference divergence envelope contains the standard envelope, with equality when ${Y}\mid{X}$ has a linear conditional mean. We develop an estimation procedure that first obtains the martingale difference divergence envelope and then estimates the additional envelope components in the central mean envelope. We establish consistency in envelope estimation of the martingale difference divergence envelope and central mean envelope without stringent model assumptions. Simulations and real-data analysis demonstrate the advantages of the martingale difference divergence envelope and the central mean envelope over the standard envelope in dimension reduction.
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Abstract
Summary
We propose a new nonparametric conditional mean independence test for a response variable $Y$ and a predictor variable $X$ where either or both can be function-valued. Our test is built on a new metric, the so-called functional martingale difference divergence, which fully characterizes the conditional mean dependence of $Y$ given $X$ and extends the martingale difference divergence proposed by Shao & Zhang (2014). We define an unbiased estimator of functional martingale difference divergence by using a $\mathcal{U}$-centring approach, and we obtain its limiting null distribution under mild assumptions. Since the limiting null distribution is not pivotal, we use the wild bootstrap method to estimate the critical value and show the consistency of the bootstrap test. Our test can detect the local alternative which approaches the null at the rate of $n^{-1/2}$ with a nontrivial power, where $n$ is the sample size. Unlike the three tests developed by Kokoszka et al. (2008), Lei (2014) and Patilea et al. (2016), our test does not require a finite-dimensional projection or assume a linear model, and it does not involve any tuning parameters. Promising finite-sample performance is demonstrated via simulations, and a real-data illustration is used to compare our test with existing ones.
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Wang PH, Lee CE, Lin YS, Lee MH, Chen PY, Chang HC, Chang IF. The Glutamate Receptor-Like Protein GLR3.7 Interacts With 14-3-3ω and Participates in Salt Stress Response in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2019; 10:1169. [PMID: 31632419 DOI: 10.3389/fpls.2019.01169/full] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 08/27/2019] [Indexed: 05/25/2023]
Abstract
Ionotropic glutamate receptors (iGluRs) are ligand-gated cation channels that mediate fast excitatory neurotransmission in the mammalian central nervous system. In the model plant Arabidopsis thaliana, a family of 20 glutamate receptor-like proteins (GLRs) shares similarities to animal iGluRs in sequence and predicted secondary structure. However, the function of GLRs in plants is little known. In the present study, a serine site (Ser-860) of AtGLR3.7 phosphorylated by a calcium-dependent protein kinase (CDPK) was identified and confirmed by an in vitro kinase assay. Using a bimolecular fluorescence complementation and quartz crystal microbalance analyses, the physical interaction between AtGLR3.7 and the 14-3-3ω protein was confirmed. The mutation of Ser-860 to alanine abolished this interaction, indicating that Ser-860 is the 14-3-3ω binding site of AtGLR3.7. Compared with wild type, seed germination of the glr3.7-2 mutant was more sensitive to salt stress. However, the primary root growth of GLR3.7-S860A overexpression lines was less sensitive to salt stress than that of the wild-type line. In addition, the increase of cytosolic calcium ion concentration by salt stress was significantly lower in the glr3.7-2 mutant line than in the wild-type line. Moreover, association of 14-3-3 proteins to microsomal fractions was less in GLR3.7-S860A overexpression lines than in GLR3.7 overexpression line under 150 mM NaCl salt stress condition. Overall, our results indicated that GLR3.7 is involved in salt stress response in A. thaliana by affecting calcium signaling.
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Burke MM, Lee CE, Rios K. A pilot evaluation of an advocacy programme on knowledge, empowerment, family-school partnership and parent well-being. JOURNAL OF INTELLECTUAL DISABILITY RESEARCH : JIDR 2019; 63:969-980. [PMID: 30815933 DOI: 10.1111/jir.12613] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 02/05/2019] [Accepted: 02/06/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND Internationally, it has been recognised that parents need to advocate for their children with disabilities to receive services. However, many parents find advocacy difficult because of systemic and logistical barriers. As such, parents of children with disabilities may seek a special education advocate to help them understand their child's rights and secure services. Yet little research has been conducted about programmes to develop special education advocates. METHODS In this study, we conducted a comparison study to determine the association of an advocacy programme (i.e. the Volunteer Advocacy Project) on a primary outcome (i.e. special education knowledge) and other outcomes (i.e. family-school partnership, empowerment and parent well-being). Specifically, in 2017, 34 participants, all mothers of children with disabilities, were recruited from disability organisations in the USA. Seventeen mothers participated in the intervention group (i.e. the advocacy training), while 17 mothers participated in the wait list control group. The Volunteer Advocacy Project is a 36 hr advocacy training for individuals to gain instrumental and affective knowledge to advocate for their own children with disabilities and for other families. All participants completed a pre-survey and post-survey; only intervention group participants completed a 6-month follow-up survey. RESULTS Compared with 17 wait list control group participants, the 17 intervention group participants demonstrated improvements in special education knowledge, P = 0.002, η2 = 0.32, and self-mastery, P = 0.04, η2 = 0.15, and decreases in the quality of family-school partnerships, P = 0.002, η2 = 0.32. At the follow-up survey, intervention group participants demonstrated increases in empowerment, P = 0.04, η2 = 0.29, and special education knowledge, P = 0.02, η2 = 0.38. CONCLUSIONS Implications for research including the need for a randomised controlled trial are discussed; also, practitioners need to evaluate advocacy training programmes regarding their effectiveness.
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Coles CE, Griffin CL, Kirby AM, Haviland JS, Titley JC, Benstead K, Brunt AM, Chan C, Ciurlionis L, Din OS, Donovan EM, Eaton DJ, Harnett AN, Hopwood P, Jefford ML, Jenkins PJ, Lee CE, McCormack M, Sherwin L, Syndikus I, Tsang Y, Twyman NI, Ventikaraman R, Wickers S, Wilcox MH, Bliss JM, Yarnold JR. Abstract GS4-05: Dose escalated simultaneous integrated boost radiotherapy for women treated by breast conservation surgery for early breast cancer: 3-year adverse effects in the IMPORT HIGH trial (CRUK/06/003). Cancer Res 2019. [DOI: 10.1158/1538-7445.sabcs18-gs4-05] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background
IMPORT HIGH is a randomised, multi-centre phase III trial testing dose escalated simultaneous integrated boost (SIB) against sequential boost each delivered by intensity modulated radiotherapy (IMRT) for early stage breast cancer with higher risk of local relapse. The primary endpoint was initially breast induration at 3 years, requiring 840 patients; accrual was extended (target 2568) with the new primary endpoint of local relapse. We report adverse effects (AE) at 3 years.
Methods
Women age ≥18 after breast conservation surgery for pT1-3 pN0-pN3a M0 invasive carcinoma were eligible. Randomisation was 1:1:1 between 40Gy/15F to whole breast (WB) + 16Gy/8F sequential photon boost to tumour bed (40+16Gy), 36Gy/15F to WB, 40Gy to partial breast + 48Gy (48Gy) or + 53Gy (53Gy) in 15F SIB to tumour bed. AEs were assessed annually by clinicians in all patients and in a planned sub-set (840) of patients by photographs at 3 years and by patients at 6 months, 1 and 3 years. AE scores were dichotomised as none/mild vs marked for photographs and none/mild vs moderate/marked for patients and clinicians. Fisher's exact tests compared groups; principal comparison (protocol-specified) between 53Gy and 48Gy (p<0.01 defined as statistical significance).
Results
2617 women consented between 03/2009 and 09/2015 from 39 UK radiotherapy centres. Median follow-up was 49.1 (IQR 36.8-63.2) months. Median age was 49 (IQR 44-56); 9%, 38% & 53% were tumour grade 1, 2 & 3 respectively; 30% were node positive. 66% received chemotherapy and 73% endocrine therapy. 3-year AE data were available for 2017 clinician assessments, 641 photographs and 842 patient assessments. Proportions of patients with marked AEs were low overall. Rates of moderate/marked AEs at 3 years were broadly similar between the randomised groups; with a suggestion of a slightly increased risk for breast induration in 53Gy compared with control (borderline significance).
AE at 3 years 40+16Gy n(%)48Gy n(%)53Gy n(%)ClinicianBreast induration;N656668654None451 (69)483 (72)445 (68)Mild167 (25)141 (21)146 (22)Moderate32 (5)42 (6)56 (9)Marked6 (1)2 (1)7 (1)P-value 0.57010.0102 0.0443Breast shrinkage;N655669654None442 (68)472 (71)448 (69)Mild167 (26)161 (24)166 (25)Moderate40 (6)33 (5)35 (5)Marked6 (1)3 (1)5 (1)P-value 0.25410.5772 0.6373Breast distortion;N656669654None451 (69)464 (69)442 (68)Mild169 (26)170 (25)170 (26)Moderate33 (5)32 (5)38 (6)Marked3 (1)3 (1)4 (1)P-value 0.90310.4862 0.4113PatientChange in breast appearance;N287264285None38 (13)50 (19)58 (20)Mild164 (57)151 (57)142 (50)Moderate57 (20)45 (17)54 (19)Marked28 (10)18 (7)31 (11)P-value 0.14910.9992 0.1243PhotographChange in breast appearance;N218210213None183 (84)185 (88)177 (83)Mild25 (11)23 (11)32 (15)Marked10 (5)2 (1)4 (2)P-value 0.03610.1732 0.6853148Gy v 40+16Gy; 253Gy v 40+16Gy; 353Gy v 48Gy
Conclusions
These results represent the largest and most mature reported AE outcomes of breast SIB within a clinical trial. At 3 years, rates of moderate/marked AEs were similar between SIB IMRT and WB + sequential boost IMRT delivered over 3 and 4.5 weeks respectively.
Citation Format: Coles CE, Griffin CL, Kirby AM, Haviland JS, Titley JC, Benstead K, Brunt AM, Chan C, Ciurlionis L, Din OS, Donovan EM, Eaton DJ, Harnett AN, Hopwood P, Jefford ML, Jenkins PJ, Lee CE, McCormack M, Sherwin L, Syndikus I, Tsang Y, Twyman NI, Ventikaraman R, Wickers S, Wilcox MH, Bliss JM, Yarnold JR. Dose escalated simultaneous integrated boost radiotherapy for women treated by breast conservation surgery for early breast cancer: 3-year adverse effects in the IMPORT HIGH trial (CRUK/06/003) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr GS4-05.
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Wang PH, Lee CE, Lin YS, Lee MH, Chen PY, Chang HC, Chang IF. The Glutamate Receptor-Like Protein GLR3.7 Interacts With 14-3-3ω and Participates in Salt Stress Response in Arabidopsis thaliana. FRONTIERS IN PLANT SCIENCE 2019; 10:1169. [PMID: 31632419 PMCID: PMC6779109 DOI: 10.3389/fpls.2019.01169] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 08/27/2019] [Indexed: 05/19/2023]
Abstract
Ionotropic glutamate receptors (iGluRs) are ligand-gated cation channels that mediate fast excitatory neurotransmission in the mammalian central nervous system. In the model plant Arabidopsis thaliana, a family of 20 glutamate receptor-like proteins (GLRs) shares similarities to animal iGluRs in sequence and predicted secondary structure. However, the function of GLRs in plants is little known. In the present study, a serine site (Ser-860) of AtGLR3.7 phosphorylated by a calcium-dependent protein kinase (CDPK) was identified and confirmed by an in vitro kinase assay. Using a bimolecular fluorescence complementation and quartz crystal microbalance analyses, the physical interaction between AtGLR3.7 and the 14-3-3ω protein was confirmed. The mutation of Ser-860 to alanine abolished this interaction, indicating that Ser-860 is the 14-3-3ω binding site of AtGLR3.7. Compared with wild type, seed germination of the glr3.7-2 mutant was more sensitive to salt stress. However, the primary root growth of GLR3.7-S860A overexpression lines was less sensitive to salt stress than that of the wild-type line. In addition, the increase of cytosolic calcium ion concentration by salt stress was significantly lower in the glr3.7-2 mutant line than in the wild-type line. Moreover, association of 14-3-3 proteins to microsomal fractions was less in GLR3.7-S860A overexpression lines than in GLR3.7 overexpression line under 150 mM NaCl salt stress condition. Overall, our results indicated that GLR3.7 is involved in salt stress response in A. thaliana by affecting calcium signaling.
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Hsieh CT, Chen YF, Lee CE, Juang SH, Lin ZW, Huq MM. Enhancing thermal transport efficiency in carbon composites using nanospacers. RSC Adv 2016. [DOI: 10.1039/c6ra09074e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Improved thermal transport efficiency of carbon-based composites has been achieved by inserting metallic spacers within the temperature range of 50–150 °C.
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Hsieh CT, Lee CE, Chen YF, Chang JK, Teng HS. Thermal conductivity from hierarchical heat sinks using carbon nanotubes and graphene nanosheets. NANOSCALE 2015; 7:18663-18670. [PMID: 26498343 DOI: 10.1039/c5nr04993h] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The in-plane (kip) and through-plane (ktp) thermal conductivities of heat sinks using carbon nanotubes (CNTs), graphene nanosheets (GNs), and CNT/GN composites are extracted from two experimental setups within the 323-373 K temperature range. Hierarchical three-dimensional CNT/GN frameworks display higher kip and ktp values, as compared to the CNT- and GN-based heat sinks. The kip and ktp values of the CNT/GN-based heat sink reach as high as 1991 and 76 W m(-1) K(-1) at 323 K, respectively. This improved thermal conductivity is attributed to the fact that the hierarchical heat sink offers a stereo thermal conductive network that combines point, line, and plane contact, leading to better heat transport. Furthermore, the compression treatment provided an efficient route to increase both kip and ktp values. This result reveals that the hierarchical carbon structures become denser, inducing more thermal conductive area and less thermal resistivity, i.e., a reduced possibility of phonon-boundary scattering. The correlation between thermal and electrical conductivity (ε) can be well described by two empirical equations: kip = 567 ln(ε) + 1120 and ktp = 20.6 ln(ε) + 36.1. The experimental results are obtained within the temperature range of 323-373 K, suitably complementing the thermal management of chips for consumer electronics.
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Chen HS, Liang YT, Chen TY, Tseng YC, Liu CW, Chung SR, Hsieh CT, Lee CE, Wang KW. Graphene-supported Pt and PtPd nanorods with enhanced electrocatalytic performance for the oxygen reduction reaction. Chem Commun (Camb) 2014; 50:11165-8. [DOI: 10.1039/c4cc04595e] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The combinational modification of the morphology, alloying, and support for Pt catalysts has been optimized towards the oxygen reduction reaction.
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Anastasopoulos A, Davies JC, Hannah L, Hayden BE, Lee CE, Milhano C, Mormiche C, Offin L. The particle size dependence of the oxygen reduction reaction for carbon-supported platinum and palladium. CHEMSUSCHEM 2013; 6:1973-1982. [PMID: 24115683 DOI: 10.1002/cssc.201300208] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 06/04/2013] [Indexed: 06/02/2023]
Abstract
Model carbon supported Pt and Pd electrocatalysts have been prepared using a high-throughput physical vapor deposition method. For Pt, metal particle sizes are controlled between 1.5-5.5 nm over 100 electrodes of an electrochemical screening chip, allowing the oxygen reduction reaction (ORR) activity of the catalysts to be determined simultaneously. The ORR-specific current density is observed to increase with increasing particle diameter up to approximately 4 nm, at which point the activity begins to level off. The reduction in ORR activity for particles below 4 nm is accompanied by a concomitant increase in the overpotential for surface reduction. The resulting mass activity exhibits a maximum for particles with diameters of approximately 3.5 nm. These results are consistent with results published recently for high area carbon-supported Pt catalysts. For Pd particles, both the specific current density and the mass-specific activity for the ORR are observed to increase with increasing particle diameter, with no distinct optimum observed. The implications for the optimization of Pt- or Pd-based ORR catalysts for proton exchange membrane fuel cell (PEMFC) applications are discussed.
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Lee CE, Leslie WD, Czaykowski P, Gingerich J, Geirnaert M, Lau YKJ. A comprehensive bone-health management approach for men with prostate cancer receiving androgen deprivation therapy. ACTA ACUST UNITED AC 2011; 18:e163-72. [PMID: 21874106 DOI: 10.3747/co.v18i4.746] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
For advanced and metastatic prostate cancer, androgen deprivation therapy (adt) is the mainstay of treatment. Awareness of the potential bone-health complications consequent to adt use is increasing. Many studies have shown that prolonged adt leads to significant bone loss and increased fracture risk that negatively affect quality of life. Clinical practice guidelines for preserving bone health in men with prostate cancer on adt vary across Canada. This paper reviews recent studies on bone health in men with prostate cancer receiving adt and the current evidence regarding bone-health monitoring and management in reference to Canadian provincial guidelines. Based on this narrative review, we provide general bone-health management recommendations for men with prostate cancer receiving adt.
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Lee KM, Choi WI, Koh DI, Kim YJ, Jeon BN, Yoon JH, Lee CE, Kim SH, Oh J, Hur MW. The proto-oncoprotein KR-POK represses transcriptional activation of CDKN1A by MIZ-1 through competitive binding. Oncogene 2011; 31:1442-58. [DOI: 10.1038/onc.2011.331] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Lim PL, Ling ML, Lee HY, Koh TH, Tan AL, Kuijper EJ, Goh SS, Low BS, Ang LP, Harmanus C, Lin RT, Krishnan P, James L, Lee CE. Isolation of the first three cases of Clostridium difficile polymerase chain reaction ribotype 027 in Singapore. Singapore Med J 2011; 52:361-364. [PMID: 21633771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
INTRODUCTION The incidence of Clostridium (C.) difficile infection (CDI) was on the rise from 2001 to 2006 in Singapore. Recent unpublished data suggests that its incidence had remained stable or decreased in most local public hospitals between 2006 and 2010. It is, however, not known if the polymerase chain reaction (PCR) ribotype 027 strains have been circulating, although reports suggest that this strain is emerging in Asia, with the first cases reported from Japan in 2007, as well as in Hong Kong and Australia in 2009. We initiated a culture-based surveillance to detect this epidemic strain in Singapore. METHODS From September 2008 to December 2009, all non-duplicate toxin-positive stool samples from the three largest public hospitals in Singapore were collected for culture and further analysis. RESULTS Out of the 366 samples collected, 272 viable isolates were cultured. Of these, 240 tested toxin-positive and ten tested positive for the binary toxin gene; 35 different PCR ribotypes were found. Three isolates that tested positive for binary toxin contained the same PCR ribotyping pattern as the C. difficile 027 control strain. All three had the 18-bp deletion and single nucleotide tcdC deletion at position 117. Susceptibility testing was performed, demonstrating susceptibility to erythromycin and moxifloxacin. CONCLUSION We report the first three isolates of C. difficile 027 from Singapore. However, their susceptibility patterns are more consistent with the historical 027 strains. Rising CDI incidence may not be associated with the emergence of the epidemic 027 strain at this time.
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Cravo RM, Margatho LO, Osborne-Lawrence S, Donato J, Atkin S, Bookout AL, Rovinsky S, Frazão R, Lee CE, Gautron L, Zigman JM, Elias CF. Characterization of Kiss1 neurons using transgenic mouse models. Neuroscience 2010; 173:37-56. [PMID: 21093546 DOI: 10.1016/j.neuroscience.2010.11.022] [Citation(s) in RCA: 243] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Revised: 11/09/2010] [Accepted: 11/11/2010] [Indexed: 10/18/2022]
Abstract
Humans and mice with loss-of-function mutations of the genes encoding kisspeptins (Kiss1) or kisspeptin receptor (Kiss1r) are infertile due to hypogonadotropic hypogonadism. Within the hypothalamus, Kiss1 mRNA is expressed in the anteroventral periventricular nucleus (AVPV) and the arcuate nucleus (Arc). In order to better study the different populations of kisspeptin cells we generated Kiss1-Cre transgenic mice. We obtained one line with Cre activity specifically within Kiss1 neurons (line J2-4), as assessed by generating mice with Cre-dependent expression of green fluorescent protein or β-galactosidase. Also, we demonstrated Kiss1 expression in the cerebral cortex and confirmed previous data showing Kiss1 mRNA in the medial nucleus of amygdala and anterodorsal preoptic nucleus. Kiss1 neurons were more concentrated towards the caudal levels of the Arc and higher leptin-responsivity was observed in the most caudal population of Arc Kiss1 neurons. No evidence for direct action of leptin in AVPV Kiss1 neurons was observed. Melanocortin fibers innervated subsets of Kiss1 neurons of the preoptic area and Arc, and both populations expressed melanocortin receptors type 4 (MC4R). Specifically in the preoptic area, 18-28% of Kiss1 neurons expressed MC4R. In the Arc, 90% of Kiss1 neurons were glutamatergic, 50% of which also were GABAergic. In the AVPV, 20% of Kiss1 neurons were glutamatergic whereas 75% were GABAergic. The differences observed between the Kiss1 neurons in the preoptic area and the Arc likely represent neuronal evidence for their differential roles in metabolism and reproduction.
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Lee CE, Zain AA, Pang YK. Antiphospholipid syndrome with pulmonary artery embolism and multiple venous thromboses. THE MEDICAL JOURNAL OF MALAYSIA 2010; 65:221-223. [PMID: 21939173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report a case of a 21-year-old university student with underlying lupus nephritis who presented with recurrent symptoms of fever, haemoptysis, and pleuritic chest pain. CT pulmonary angiogram confirmed pulmonary embolism in the right subsegmental pulmonary arteries. One week later, she developed left renal vein and left common iliac vein thromboses, with new emboli in the left subsegmental pulmonary arteries. We hereforth discuss the diagnostic issues of a patient with systemic lupus erythematosus (SLE) on corticosteroids therapy, and also treatment of the antiphospholipid syndrome.
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Lee CE, Zanariah H, Masni M, Pau KK. Solitary fibrous tumour of the pleura presenting with refractory non-insulin mediated hypoglycaemia (the Doege-Potter syndrome). THE MEDICAL JOURNAL OF MALAYSIA 2010; 65:72-74. [PMID: 21265256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report a case of a 61 year-old man who presented with refractory non-insulin mediated hypoglycaemia. A chest radiograph showed a right lung opacity, which was confirmed as a large intra-thoracic mass by computed tomography (CT) of the thorax. CT-guided biopsy with histological examination revealed features of a solitary fibrous tumour of low malignant potential. We discuss the association of solitary fibrous tumour of the pleura (SFTP) with hypoglycaemia, and the management of such rare tumours.
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Lee CE, Adeeba K, Freigang G. Human Plasmodium knowlesi infections in Klang Valley, Peninsula Malaysia: a case series. THE MEDICAL JOURNAL OF MALAYSIA 2010; 65:63-65. [PMID: 21265252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report seven cases of naturally acquired human Plasmodium knowlesi infections which were admitted to our centre from July 2007 till June 2008. Diagnosis was confirmed by nested PCR. Cases of P. knowlesi infections, dubbed the fifth type of human malaria, have been reported in East Malaysia (Sabah and Sarawak) as well as in the state of Pahang in Peninsula Malaysia. These seven patients appear to be the first few reported cases of P. knowlesi infection in the Klang valley, Peninsula Malaysia. We then discuss the characteristics of human P. knowlesi infections, which include its natural hosts, responsible vectors, clinical presentation, and the treatment of such infections.
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Lee CE, Shaiful AY, Hanif H. Subclavian artery stent fracture. THE MEDICAL JOURNAL OF MALAYSIA 2009; 64:330-332. [PMID: 20954563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report a case of a 52 year-old dentist who had stent implantation for a left subclavian artery stenosis. However, this was later complicated by a stent fracture within one week of stent placement. A chest radiograph showed two pieces of the fractured stent, which was confirmed by computed tomographic angiogram (CTA) of the affected artery. We then discuss the occurrence of stent fractures, which are not uncommon but serious complications of endovascular therapy.
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Sarkar SA, Kutlu B, Velmurugan K, Kizaka-Kondoh S, Lee CE, Wong R, Valentine A, Davidson HW, Hutton JC, Pugazhenthi S. Cytokine-mediated induction of anti-apoptotic genes that are linked to nuclear factor kappa-B (NF-kappaB) signalling in human islets and in a mouse beta cell line. Diabetologia 2009; 52:1092-101. [PMID: 19343319 DOI: 10.1007/s00125-009-1331-x] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2008] [Accepted: 02/13/2009] [Indexed: 12/23/2022]
Abstract
AIMS/HYPOTHESIS The destruction of pancreatic beta cells leading to type 1 diabetes in humans is thought to occur mainly through apoptosis and necrosis induced by activated macrophages and T cells, and in which secreted cytokines play a significant role. The transcription factor nuclear factor kappa-B (NF-kappaB) plays an important role in mediating the apoptotic action of cytokines in beta cells. We therefore sought to determine the changes in expression of genes modulated by NF-kappaB in human islets exposed to a combination of IL1beta, TNF-alpha and IFN-gamma. METHODS Microarray and gene set enrichment analysis were performed to investigate the global response of gene expression and pathways modulated in cultured human islets exposed to cytokines. Validation of a panel of NF-kappaB-regulated genes was performed by quantitative RT-PCR. The mechanism of induction of BIRC3 by cytokines was examined by transient transfection of BIRC3 promoter constructs linked to a luciferase gene in MIN6 cells, a mouse beta cell line. RESULTS Enrichment of several metabolic and signalling pathways was observed in cytokine-treated human islets. In addition to the upregulation of known pro-apoptotic genes, a number of anti-apoptotic genes including BIRC3, BCL2A1, TNFAIP3, CFLAR and TRAF1 were induced by cytokines through NF-kappaB. Significant synergy between the cytokines was observed in NF-kappaB-mediated induction of the promoter of BIRC3 in MIN6 cells. CONCLUSIONS/INTERPRETATION These findings suggest that, via NF-kappaB activation, cytokines induce a concurrent anti-apoptotic pathway that may be critical for preserving islet integrity and viability during the progression of insulitis in type 1 diabetes.
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Lee CE. Tackling Subutex abuse in Singapore. Singapore Med J 2006; 47:919-21. [PMID: 17075655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
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