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Fong J, Lee SHR, Sun Y, Lim CL, Tan YAJ, Tan YH, Neo ML. Litter traps: A comparison of four marine habitats as sinks for anthropogenic marine macro-litter in Singapore. Mar Pollut Bull 2023; 196:115645. [PMID: 37862845 DOI: 10.1016/j.marpolbul.2023.115645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 05/18/2023] [Accepted: 10/06/2023] [Indexed: 10/22/2023]
Abstract
The potential for marine litter being trapped in biodiverse marine habitats such as mangrove forests, seagrass meadows and coral reefs is poorly understood. This study presents the first comprehensive investigation on the status of macro-litter across four marine habitats in Singapore during the two monsoonal seasons. Overall, litter density did not vary considerably between the southwest and the northeast monsoon. The litter density in terms of count was generally lower in seagrass meadows and coral reefs compared to mangroves and beaches. Plastic was the major type of litter found across most habitat types. Notably, many fishing-related items were found on coral reefs, while drinking straws were abundant at the mangrove strandlines during the southwest monsoon. Foam fragments and cigarette butts were common at the beach strandlines. These results suggest that mangroves among other habitats examined here should be prioritised for clean-up efforts in order to restore these critical coastal habitats.
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Affiliation(s)
- Jenny Fong
- Tropical Marine Science Institute, National University of Singapore, 18 Kent Ridge Road, Singapore 119227, Singapore.
| | - Samuel Hsien Rong Lee
- Tropical Marine Science Institute, National University of Singapore, 18 Kent Ridge Road, Singapore 119227, Singapore
| | - Yuchen Sun
- Tropical Marine Science Institute, National University of Singapore, 18 Kent Ridge Road, Singapore 119227, Singapore
| | - Cheng Ling Lim
- Centre for International Law, National University of Singapore, 469A Bukit Timah Road, Singapore 259770, Singapore
| | - Yean Ai Jolin Tan
- Republic Polytechnic, 9 Woodlands Avenue 9, Singapore 738964, Singapore
| | - Yi Hong Tan
- Tropical Marine Science Institute, National University of Singapore, 18 Kent Ridge Road, Singapore 119227, Singapore
| | - Mei Lin Neo
- Tropical Marine Science Institute, National University of Singapore, 18 Kent Ridge Road, Singapore 119227, Singapore.
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2
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Omeyer LCM, Duncan EM, Abreo NAS, Acebes JMV, AngSinco-Jimenez LA, Anuar ST, Aragones LV, Araujo G, Carrasco LR, Chua MAH, Cordova MR, Dewanti LP, Espiritu EQ, Garay JB, Germanov ES, Getliff J, Horcajo-Berna E, Ibrahim YS, Jaafar Z, Janairo JIB, Gyi TK, Kreb D, Lim CL, Lyons Y, Mustika PLK, Neo ML, Ng SZH, Pasaribu B, Pariatamby A, Peter C, Porter L, Purba NP, Santa Cruz ET, Shams S, Thompson KF, Torres DS, Westerlaken R, Wongtawan T, Godley BJ. Interactions between marine megafauna and plastic pollution in Southeast Asia. Sci Total Environ 2023; 874:162502. [PMID: 36868274 DOI: 10.1016/j.scitotenv.2023.162502] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 02/22/2023] [Accepted: 02/23/2023] [Indexed: 06/18/2023]
Abstract
Southeast (SE) Asia is a highly biodiverse region, yet it is also estimated to cumulatively contribute a third of the total global marine plastic pollution. This threat is known to have adverse impacts on marine megafauna, however, understanding of its impacts has recently been highlighted as a priority for research in the region. To address this knowledge gap, a structured literature review was conducted for species of cartilaginous fishes, marine mammals, marine reptiles, and seabirds present in SE Asia, collating cases on a global scale to allow for comparison, coupled with a regional expert elicitation to gather additional published and grey literature cases which would have been omitted during the structured literature review. Of the 380 marine megafauna species present in SE Asia, but also studied elsewhere, we found that 9.1 % and 4.5 % of all publications documenting plastic entanglement (n = 55) and ingestion (n = 291) were conducted in SE Asian countries. At the species level, published cases of entanglement from SE Asian countries were available for 10 % or less of species within each taxonomic group. Additionally, published ingestion cases were available primarily for marine mammals and were lacking entirely for seabirds in the region. The regional expert elicitation led to entanglement and ingestion cases from SE Asian countries being documented in 10 and 15 additional species respectively, highlighting the utility of a broader approach to data synthesis. While the scale of the plastic pollution in SE Asia is of particular concern for marine ecosystems, knowledge of its interactions and impacts on marine megafauna lags behind other areas of the world, even after the inclusion of a regional expert elicitation. Additional funding to help collate baseline data are critically needed to inform policy and solutions towards limiting the interactions of marine megafauna and plastic pollution in SE Asia.
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Affiliation(s)
- Lucy C M Omeyer
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9EZ, United Kingdom
| | - Emily M Duncan
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9EZ, United Kingdom; Institute of Marine Sciences-Okeanos, University of the Azores, Rua Professor Doutor Frederico Machado 4, 9901-862 Horta, Portugal.
| | - Neil Angelo S Abreo
- AI and Robotics Laboratory-Environmental Studies, University of the Philippines, Mindanao, Philippines
| | - Jo Marie V Acebes
- BALYENA.ORG, Jagna, Bohol, Philippines; Zoology Division, The National Museum of the Philippines, Padre Burgos Avenue, Manila, Philippines
| | - Lea A AngSinco-Jimenez
- Regional Integrated Coastal Resource Management Center (RIC-XI), hosted by Davao Oriental State University (DOrSU), City of Mati, Davao Oriental, Philippines
| | - Sabiqah T Anuar
- Microplastic Research Interest Group (MRIG), Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
| | - Lemnuel V Aragones
- Marine Mammal Research & Conservation Laboratory, Institute of Environmental Science and Meteorology, College of Science, University of the Philippines Diliman, Quezon City, Philippines
| | - Gonzalo Araujo
- Marine Research and Conservation Foundation, Lydeard St Lawrence, Somerset, United Kingdom; Environmental Science Program, Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, Doha, Qatar
| | - Luis R Carrasco
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117543, Singapore
| | - Marcus A H Chua
- Lee Kong Chian Natural History Museum, National University of Singapore, 2 Conservatory Drive, Singapore 117377, Singapore
| | - Muhammad R Cordova
- Research Centre for Oceanography, The Indonesian National Research and Innovation Agency (BRIN), BRIN Kawasan Jakarta Ancol Jalan Pasir Putih 1, Ancol Timur, Jakarta 14430, Indonesia
| | - Lantun P Dewanti
- Fishery Department, Faculty of Fishery and Marine Science, Universitas Padjadjaran, 40600 Bandung, Indonesia
| | - Emilyn Q Espiritu
- Department of Environmental Science, Ateneo de Manila University, Loyola Heights, 1108 Quezon City, Philippines
| | - Jovanie B Garay
- Davao Oriental State University (DOrSU), San Isidro Extension Campus, San Isidro, Davao Oriental, Philippines
| | - Elitza S Germanov
- Marine Megafauna Foundation, West Palm Beach, FL, United States of America; Centre for Sustainable Aquatic Ecosystems, Harry Butler Institute, Murdoch University, Perth, Western Australia, Australia; Environmental and Conservation Sciences, Murdoch University, Perth, Western Australia, Australia
| | - Jade Getliff
- Roctopus ecoTrust, Roctopus Dive, Sairee Beach, Koh Tao 84360, Thailand
| | | | - Yusof S Ibrahim
- Microplastic Research Interest Group (MRIG), Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
| | - Zeehan Jaafar
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117543, Singapore; Tropical Marine Science Institute, National University of Singapore, 18 Kent Ridge Road, 119227, Singapore
| | - Jose Isagani B Janairo
- Department of Biology, De La Salle University, 2401 Taft Avenue, 0922 Manila, Philippines
| | - Thanda Ko Gyi
- Myanmar Ocean Project, 24 Myaing Hay Wun Housing, Yangon 11061, Myanmar
| | - Danielle Kreb
- Yayasan Konservasi RASI/Laboratory of Hydro-Oceanography, Faculty of Fisheries, Mulawarman University, Samarinda, Indonesia
| | - Cheng Ling Lim
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117543, Singapore
| | - Youna Lyons
- Centre for International Law, National University of Singapore, Bukit Timah Campus, 259770, Singapore
| | - Putu L K Mustika
- College of Business, Law and Governance, James Cook University, Townsville, Australia; Cetacean Sirenian Indonesia, Jakarta, Indonesia; Whale Stranding Indonesia, Jakarta, Indonesia
| | - Mei Lin Neo
- Tropical Marine Science Institute, National University of Singapore, 18 Kent Ridge Road, 119227, Singapore
| | - Sirius Z H Ng
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, 117543, Singapore
| | - Buntora Pasaribu
- Marine Science Department, Faculty of Fishery and Marine Science, Universitas Padjadjaran, 40600 Bandung, Indonesia
| | - Agamuthu Pariatamby
- Jeffrey Sachs Centre on Sustainable Development, Sunway University, Selangor Darul Ehsan 47500, Malaysia
| | - Cindy Peter
- Institute of Biodiversity and Environmental Conservation, Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia
| | - Lindsay Porter
- The Institute of Marine Ecology and Conservation (IMEC), National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Noir P Purba
- Marine Science Department, Faculty of Fishery and Marine Science, Universitas Padjadjaran, 40600 Bandung, Indonesia
| | - Ernesto T Santa Cruz
- Consultant on Environmental Affairs, Independent Researcher, Davao City, Philippines
| | - Shahriar Shams
- Civil Engineering Programme Area, Universiti Teknologi Brunei, Jalan Tungku Link, Gadong, BE 1410, Brunei Darussalam
| | - Kirsten F Thompson
- Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, Devon, United Kingdom
| | - Daniel S Torres
- Independent Marine Megafauna Researcher, Quezon City, Philippines
| | - Rodney Westerlaken
- Westerlaken Foundation, Yayasan Bali Bersih, Indonesia; Hotel Management School, NHL Stenden University, Leeuwarden, the Netherlands; Faculty of Environmental Science, Udayana University, Indonesia
| | - Tuempong Wongtawan
- Marine Animal Research and Rescue Centre, Akkhraratchakumari Veterinary College, Walailak University, Thai Buri, Tha Sala, Nakhon Si Thammarat 80160, Thailand; Centre for One Health, Akkhraratchakumari Veterinary College, Walailak University, Thai Buri, Tha Sala, Nakhon Si Thammarat 80160, Thailand; Centre of Excellence for Coastal Resource Management with Communal Participation, Walailak University, Thai Buri, Tha Sala, Nakhon Si Thammarat 80160, Thailand
| | - Brendan J Godley
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9EZ, United Kingdom
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Loo G, Yap J, Hon JS, Ismail A, Lim CL, Sumanthy P, Ruan W, Sewa DW, Phua GC, Ng SA, Hong C, Low A, Lim ST, Tan JL. Real-world outcomes of Selexipag for treatment of pulmonary hypertension in an Asian population. Eur Heart J 2023. [DOI: 10.1093/eurheartj/ehac779.081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Introduction
Selexipag is an oral selective prostacyclin IP receptor agonist indicated for treatment of pulmonary arterial hypertension (PAH). Data on its real-world safety and efficacy in Asians is lacking.
Purpose
We sought to evaluate the clinical characteristics, treatment regimens and outcomes of patients initiated on selexipag in a tertiary cardiac centre in Asia.
Methods
This was a retrospective study on all patients initiated on selexipag from January 2017 to December 2020. Baseline and follow up characteristics including demographics, functional status and clinical data were collected. Clinical outcomes evaluated included hospitalisation for PH related complications and all-cause mortality. Patients were risk stratified using the COMPERA 2.0 risk scores.
Results
A total of 36 PAH patients were treated with selexipag. At baseline, most patients were WHO functional class II or III (36.4% and 51.5% respectively), with a NT-proBNP of 1335 pg/ml (557 – 2918) and 6 minute walk test (6MWT) duration of 327.5 ±126.4 meters. Selexipag was initiated at 200mcg twice daily dosage for all except one patient (started at 200mcg once daily) and the maximum tolerated dose ranged from 200mcg twice daily to 1400mcg twice daily, with majority tolerating up to a dose of 600mcg twice daily (58.3%). Side effects were reported in 23 patients (63.9%), of which headache (27.8%), diarrhea (30.6%) or musculoskeletal symptoms (27.8%) were predominant. After a median follow up duration of 25.9 ± 23.1 months, selexipag was stopped in 20 patients (55.6%), of which eight patients were due to PAH progression requiring alternative therapy, and 12 patients due to side effects from selexipag. At baseline, patients were classified into low (8.3%), intermediate-low (30.6%), intermediate-high (33.3%) and high risk (27.8%) respectively. Patients who continued on selexipag at follow up showed no change (46.2%), improvement (15.4%) and deterioration (38.5%) in risk score. In the overall cohort of 36 patients, majority (75%) had at least one hospitalisation for PAH related complications and 15 patients (41.7%) demised.
Conclusion
In this real-world study, while selexipag was associated with a stable or improved PAH risk scores in majority of patients, there was a subset of patients with disease progression or intolerance to the medication. Further studies are warranted to identify patients who will benefit most from this therapy.
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Affiliation(s)
- G Loo
- National Heart Centre Singapore , Singapore , Singapore
| | - J Yap
- National Heart Centre Singapore , Singapore , Singapore
| | - J S Hon
- National Heart Centre Singapore , Singapore , Singapore
| | - A Ismail
- National Heart Centre Singapore , Singapore , Singapore
| | - C L Lim
- National Heart Centre Singapore , Singapore , Singapore
| | - P Sumanthy
- National Heart Centre Singapore , Singapore , Singapore
| | - W Ruan
- National Heart Centre Singapore , Singapore , Singapore
| | - D W Sewa
- Singapore General Hospital , Singapore , Singapore
| | - G C Phua
- Singapore General Hospital , Singapore , Singapore
| | - S A Ng
- Singapore General Hospital , Singapore , Singapore
| | - C Hong
- Singapore General Hospital , Singapore , Singapore
| | - A Low
- Singapore General Hospital , Singapore , Singapore
| | - S T Lim
- National Heart Centre Singapore , Singapore , Singapore
| | - J L Tan
- National Heart Centre Singapore , Singapore , Singapore
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Choo J, Yap J, Ismail AIDILA, Lim CL, Sumathy P, Ruan W, Sewa DW, Phua GC, Hong C, Low AHL, Lim ST, Tan JL. Intravenous epoprostenol therapy in the treatment of pulmonary arterial hypertension: the Singapore experience. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehab849.116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Background
Pulmonary arterial hypertension (PAH) is a progressive disease with significant morbidity and mortality. While intravenous (IV) Epoprostenol, a prostacyclin analogue, has been shown to improve exercise tolerance, symptoms, hemodynamics and survival, there are challenges with initiation and maintenance of this IV therapy.
Purpose
We aim to describe our local experience of the use of IV Epoprostenol in the treatment of PAH patients in Singapore, highlighting various issues and challenges.
Methods
From 2016, patients at a tertiary cardiac institution diagnosed with Group 1 PAH and remaining in intermediate to high risk class with progressive symptoms (despite being on maximum tolerable doses of PhosphoDiEsterase-5 inhibitors and Endothelin-1 receptor antagonists) were assessed and counselled for initiation of Epoprostenol therapy. With a fixed set of local protocols, comprehensive assessment and support of a multi-disciplinary team including physicians, specialist nurses and pharmacists, suitable patients were started on this treatment.
Results
A total of 12 patients (11 female, mean age 42.8 +/- 11.0 years) were included. The average New York Heart Association class of the patients initiated on Epoprostenol was II-III. The pulmonary artery pressures and pulmonary vascular resistance on right heart catheterization prior to initiation was 52.5 (IQR 47.0-54.0) mmHg and 12.6 (IQR 10.0-14.2) Woods respectively. The duration from diagnosis to time of initiating Epoprostenol was 89 (IQR 62-140) months. Epoprostenol was generally well tolerated. The most common side effect experienced was diarrhea (5/12 patients) followed by headache and musculoskeletal complains (3/12 patients each). Of the 12 patients, 6 passed away after 12 (IQR 10-16) months of Epoprostenol therapy. Of the remaining 6, PAH was diagnosed 110 (IQR 104-136) months ago and Epoprostenol therapy has been continued for 17 (IQR 14-27) months. Of those who survived, right ventricle size and PA pressures on echocardiography remained relatively stable as compared to those who passed on. 2 patients had line related infections requiring a line change 1 and 2 times respectively.
Conclusion
While not without its challenges, the establishment of concrete protocols with the support of a multidisciplinary team allows for the introduction of IV Epoprostenol as an additional potential line of effective therapy for PAH patients in Singapore.
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Affiliation(s)
- J Choo
- National Heart Centre Singapore, Singapore, Singapore
| | - J Yap
- National Heart Centre Singapore, Singapore, Singapore
| | - AIDILA Ismail
- National Heart Centre Singapore, Singapore, Singapore
| | - C L Lim
- National Heart Centre Singapore, Singapore, Singapore
| | - P Sumathy
- National Heart Centre Singapore, Singapore, Singapore
| | - W Ruan
- National Heart Centre Singapore, Singapore, Singapore
| | - D W Sewa
- Singapore General Hospital, Singapore, Singapore
| | - G C Phua
- Singapore General Hospital, Singapore, Singapore
| | - C Hong
- Singapore General Hospital, Singapore, Singapore
| | - A H L Low
- Singapore General Hospital, Singapore, Singapore
| | - S T Lim
- National Heart Centre Singapore, Singapore, Singapore
| | - J L Tan
- National Heart Centre Singapore, Singapore, Singapore
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5
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Lim CL, Prescott GW, De Alban JDT, Ziegler AD, Webb EL. Untangling the proximate causes and underlying drivers of deforestation and forest degradation in Myanmar. Conserv Biol 2017; 31:1362-1372. [PMID: 28856773 DOI: 10.1111/cobi.12984] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 06/28/2017] [Accepted: 07/04/2017] [Indexed: 05/22/2023]
Abstract
Political transitions often trigger substantial environmental changes. In particular, deforestation can result from the complex interplay among the components of a system-actors, institutions, and existing policies-adapting to new opportunities. A dynamic conceptual map of system components is particularly useful for systems in which multiple actors, each with different worldviews and motivations, may be simultaneously trying to alter different facets of the system, unaware of the impacts on other components. In Myanmar, a global biodiversity hotspot with the largest forest area in mainland Southeast Asia, ongoing political and economic reforms are likely to change the dynamics of deforestation drivers. A fundamental conceptual map of these dynamics is therefore a prerequisite for interventions to reduce deforestation. We used a system-dynamics approach and causal-network analysis to determine the proximate causes and underlying drivers of forest loss and degradation in Myanmar from 1995 to 2016 and to articulate the linkages among them. Proximate causes included infrastructure development, timber extraction, and agricultural expansion. These were stimulated primarily by formal agricultural, logging, mining, and hydropower concessions and economic investment and social issues relating to civil war and land tenure. Reform of land laws, the link between natural resource extraction and civil war, and the allocation of agricultural concessions will influence the extent of future forest loss and degradation in Myanmar. The causal-network analysis identified priority areas for policy interventions, for example, creating a public registry of land-concession holders to deter corruption in concession allocation. We recommend application of this analytical approach to other countries, particularly those undergoing political transition, to inform policy interventions to reduce forest loss and degradation.
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Affiliation(s)
- Cheng Ling Lim
- Department of Biological Sciences, National University of Singapore, Singapore, 117543, Singapore
| | - Graham W Prescott
- Department of Biological Sciences, National University of Singapore, Singapore, 117543, Singapore
| | - Jose Don T De Alban
- Department of Biological Sciences, National University of Singapore, Singapore, 117543, Singapore
| | - Alan D Ziegler
- Department of Geography, National University of Singapore, Singapore, 117570, Singapore
| | - Edward L Webb
- Department of Biological Sciences, National University of Singapore, Singapore, 117543, Singapore
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6
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Prescott GW, Sutherland WJ, Aguirre D, Baird M, Bowman V, Brunner J, Connette GM, Cosier M, Dapice D, De Alban JDT, Diment A, Fogerite J, Fox J, Hlaing W, Htun S, Hurd J, LaJeunesse Connette K, Lasmana F, Lim CL, Lynam A, Maung AC, McCarron B, McCarthy JF, McShea WJ, Momberg F, Mon MS, Myint T, Oberndorf R, Oo TN, Phelps J, Rao M, Schmidt-Vogt D, Speechly H, Springate-Baginski O, Steinmetz R, Talbott K, Than MM, Thaung TL, Thawng SCL, Thein KM, Thein S, Tizard R, Whitten T, Williams G, Wilson T, Woods K, Ziegler AD, Zrust M, Webb EL. Political transition and emergent forest-conservation issues in Myanmar. Conserv Biol 2017; 31:1257-1270. [PMID: 29030915 DOI: 10.1111/cobi.13021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Revised: 05/10/2017] [Accepted: 05/19/2017] [Indexed: 06/07/2023]
Abstract
Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long-running civil war. With these transitions in mind, we used a horizon-scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land-tenure insecurity, large-scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure- and energy-project planning, and reforming land-tenure and environmental-protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions.
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Affiliation(s)
- Graham W Prescott
- Department of Biological Sciences, National University of Singapore, Singapore, 14 Science Drive 4, 117543, Singapore
| | - William J Sutherland
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3QZ, U.K
| | - Daniel Aguirre
- International Commission of Jurists, 15, Shan Yeikthar Street, Pann Hlaing Ward, Myanmar
| | - Matthew Baird
- MatthewBaird.com.au, 309 Peaks Garden Condo, 187/14 Thanon Chang Klan, Chiang Mai, 50100, Thailand
| | - Vicky Bowman
- Myanmar Centre for Responsible Business (MCRB), No. 6 (A), Shin Saw Pu Road, Kayinchan Qtr, Ahlone, Yangon, Myanmar
| | - Jake Brunner
- IUCN Indo-Burma Group, 1st floor, Building 2A, Van Phuc Diplomatic Compound, Ba Dinh District, Hanoi, Viet Nam
| | - Grant M Connette
- Smithsonian Conservation Biology Institute, National Zoological Park, 1500 Remount Road, Front Royal, VA 22630, U.S.A
| | - Martin Cosier
- Myanmar Environmental Governance Program, U.S.-Asia Partnerships for Environmental Law, Vermont Law School, 164 Chelsea Street, P.O. Box 96, South Royalton, VT 05068, U.S.A
| | - David Dapice
- John F. Kennedy School of Government, Harvard University, 79 John F. Kennedy Street, Cambridge, MA 02138, U.S.A
| | - Jose Don T De Alban
- Department of Biological Sciences, National University of Singapore, Singapore, 14 Science Drive 4, 117543, Singapore
| | - Alex Diment
- Wildlife Conservation Society, Myanmar, 12 Narnattaw Road, Shwe Kainnayi Housing, Kamaryut Township, 11051, Yangon, Myanmar
| | - Julia Fogerite
- IUCN Myanmar, 212 Sabae Marga Street, Kamaryut, Yangon, Myanmar
| | - Jefferson Fox
- East-West Centre, 1601 East-West Road, Honolulu, HI 96848-1601, U.S.A
| | - Win Hlaing
- FLEGT Secretariat, No 58 Kyaing Tone Street, Nay Pyi Taw, Myanmar
| | - Saw Htun
- Wildlife Conservation Society, Myanmar, 12 Narnattaw Road, Shwe Kainnayi Housing, Kamaryut Township, 11051, Yangon, Myanmar
| | - Jack Hurd
- The Nature Conservancy, 4245 North Fairfax Drive, Suite 100, Arlington, VA 22203-1606, U.S.A
| | - Katherine LaJeunesse Connette
- Smithsonian Conservation Biology Institute, National Zoological Park, 1500 Remount Road, Front Royal, VA 22630, U.S.A
| | - Felicia Lasmana
- Daemeter Consulting, Jl. Tangkuban Perahu 1, Taman Kencana, Bogor, Jawa Barat, 16128, Indonesia
| | - Cheng Ling Lim
- Department of Biological Sciences, National University of Singapore, Singapore, 14 Science Drive 4, 117543, Singapore
| | - Antony Lynam
- Wildlife Conservation Society, Center for Global Conservation, 2300 Southern Boulevard, Bronx, NY 10460, U.S.A
| | - Aye Chan Maung
- Forest Research Institute, Yezin, Zeyarthiri Township, Nay Pyi Taw, Myanmar
| | - Benjamin McCarron
- Asia Research and Engagement, 10 Anson Road, #26-04, International Plaza, 079903, Singapore
| | - John F McCarthy
- Crawford School of Public Policy, Australian National University, JG Crawford Building, 132 Lennox Crossing, Acton ACT 0200, Australia
| | - William J McShea
- Smithsonian Conservation Biology Institute, National Zoological Park, 1500 Remount Road, Front Royal, VA 22630, U.S.A
| | - Frank Momberg
- Fauna & Flora International (FFI) Myanmar, No. 35, 3rd Floor, Shan Gone Condo, San Chaung Township, Yangon, Myanmar
| | - Myat Su Mon
- Forest Department, Ministry of Natural Resources and Environmental Conservation, No. 39, Nay Pyi Taw, Myanmar
| | - Than Myint
- Wildlife Conservation Society, Myanmar, 12 Narnattaw Road, Shwe Kainnayi Housing, Kamaryut Township, 11051, Yangon, Myanmar
| | - Robert Oberndorf
- USAID's Myanmar Land Tenure Project, Implemented by Tetra Tech, No. 17, Kaba Aye Pagoda Road, Yankin Township, Yangon, 11081, Myanmar
| | - Thaung Naing Oo
- Forest Research Institute, Yezin, Zeyarthiri Township, Nay Pyi Taw, Myanmar
| | - Jacob Phelps
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, U.K
| | - Madhu Rao
- Department of Biological Sciences, National University of Singapore, Singapore, 14 Science Drive 4, 117543, Singapore
- Wildlife Conservation Society, Center for Global Conservation, 2300 Southern Boulevard, Bronx, NY 10460, U.S.A
| | - Dietrich Schmidt-Vogt
- Chair of Silviculture, Faculty of Environment and Natural Resources, Freiburg University, Tennenbacherstr. 4, 79085 Freiburg, Germany
| | - Hugh Speechly
- FLEGT Secretariat, No 58 Kyaing Tone Street, Nay Pyi Taw, Myanmar
| | - Oliver Springate-Baginski
- School of International Development, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, U.K
| | - Robert Steinmetz
- WWF Thailand, 87 Soi Phatholyothin 5, Samsen Nai Phayathai, Bangkok 10400, Thailand
| | - Kirk Talbott
- Environmental Law Institute, 1730 M Street, NW, Suite 700, Washington, D.C. 20036, U.S.A
| | - Maung Maung Than
- RECOFTC, P.O. Box 1111, Kasetsart Post Office, Phahonyothin Road, Bangkok, 10903, Thailand
| | - Tint Lwin Thaung
- RECOFTC, P.O. Box 1111, Kasetsart Post Office, Phahonyothin Road, Bangkok, 10903, Thailand
| | - Salai Cung Lian Thawng
- Pyoe Pin, No. 23, 1st Floor, Strand Mansion, 40th Street, Kyauktada Township, Yangon, Myanmar
| | - Kyaw Min Thein
- Forest Department, Ministry of Natural Resources and Environmental Conservation, No. 39, Nay Pyi Taw, Myanmar
| | - Shwe Thein
- Land Core Group, 18D Sein Lei Yeik Thar Street, Yangon, Myanmar
| | - Robert Tizard
- Wildlife Conservation Society, Myanmar, 12 Narnattaw Road, Shwe Kainnayi Housing, Kamaryut Township, 11051, Yangon, Myanmar
| | - Tony Whitten
- Fauna & Flora International (FFI) Myanmar, No. 35, 3rd Floor, Shan Gone Condo, San Chaung Township, Yangon, Myanmar
| | - Guy Williams
- Environmental Resources Management, 120 Robinson Road, Singapore, #10-01, 068913, Singapore
| | - Trevor Wilson
- Crawford School of Public Policy, Australian National University, JG Crawford Building, 132 Lennox Crossing, Acton ACT 0200, Australia
| | - Kevin Woods
- Department of Environmental Science, Policy and Management, University of California Berkeley, 215 Moses Hall, Berkeley, CA 94720-2308, U.S.A
| | - Alan D Ziegler
- Department of Geography, National University of Singapore, Singapore, 1 Arts Link, 117570, Singapore
| | - Michal Zrust
- Daemeter Consulting, Jl. Tangkuban Perahu 1, Taman Kencana, Bogor, Jawa Barat, 16128, Indonesia
| | - Edward L Webb
- Department of Biological Sciences, National University of Singapore, Singapore, 14 Science Drive 4, 117543, Singapore
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7
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Koh RY, Lim CL, Ho CC, Uhal BD, Abdullah M, Vidyadaran S, Seow HF. Metabolites from Actinomyces strain H6552 extract inhibit transforming growth factor-mediated pulmonary fibrosis. TROP J PHARM RES 2014. [DOI: 10.4314/tjpr.v13i11.7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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8
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Chng J, Wan MC, Lim CL, Kang WL. A comparison of thermal stress in the submarine escape using immersion half- and full suit in tropical weather operations. Undersea Hyperb Med 2010; 37:447-454. [PMID: 21226395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
OBJECTIVE Submariners of disabled submarines are subject to drastic weather changes as they are awaiting rescue on the sea surface. Hyperthermia and hypothermia are just two of the adverse conditions that they can experience. The purpose of this study was to investigate the effectiveness of two models of submarine escape and the protective capabilities of immersion suits from environmental changes. METHOD A randomized study involving 24 male subjects was conducted to compare the thermal capabilities of the full- versus half-configuration suit in a climate-controlled chamber. RESULTS The full-configuration suits tested for a higher mean maximal core temperature (37.76 degrees C / 99.97 degrees F) than the mean maximal core temperature of the half-suits (37.52 degrees C / 99.54 degrees F). The full suits also tested for a higher mean minimal core temperature (36.13 degrees C / 97.03 degrees F) than the mean minimal core temperature (35.95 degrees C / 96.71 degrees F) of the half-suits. CONCLUSION Results showed that the full-suit configuration did not induce clinically significant high levels of heat stress as compared to the half-suits, but instead provided better thermal protection against hypothermia than the half-suits.
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Affiliation(s)
- J Chng
- Head Hyperbaric Medicine Section, Navy Medical Service, Republic of Singapore Navy, Singapore.
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9
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Abstract
The right internal jugular vein (IJV) is a common vessel to obtain venous access. It is important to have a clear understanding of the anatomy of the IJV and its relationship to the common carotid arteries (CCA) to avoid inadvertent arterial puncture. This study aims to objectively evaluate the variations in the anatomy of IJV and its relation to the CCA. A total of 176 right and left IJV were retrospectively evaluated using CT imaging with the CentraRad Diagnostic Viewer Version 4.09.0190 (CDN Telemedicine Solutions, Wollongong, Australia). The data were recorded and analysed. The right IJV (80.5%) was more often larger than the left IJV. With reference to the CCA, 85.2% of the IJV were found in the lateral position, 12.5% anteriorly, 1.1% medially and 1.1% posteriorly. Seven IJV were found to be hypoplastic, and in one case this was seen bilaterally in both the right and left IJV. The maximum depth of IJV from the skin was 27.9 mm. More than half (69.5%) of the IJV were less than 1 mm from the carotids. Computed tomography is an excellent method to delineate the anatomy of IJV. Variations in the anatomy of the IJV and their correlation to the CCA are common.
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Affiliation(s)
- C L Lim
- Department of Radiology, Queen Elizabeth Hospital, Adelaide, South Australia, Australia.
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10
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Abstract
OBJECTIVE To estimate the sudomotor nerve conduction velocity (CV), the central processing time (CPT) and habituation of the skin conductance response (SCR). METHODS SCRs in response to a single deep inspiratory breath, an electrical stimulus and a sound click were obtained from the fingers and toes of 30 healthy adults. Sudomotor nerve conduction velocities were determined after measuring extremity length and latency differences. CPT was estimated by subtracting the efferent time and the known afferent times and neuroeffector times from the onset latency. RESULTS The inspiratory SCR habituated slower than the auditory or electrical SCRs. CVs of the 3 modalities did not differ statistically and their mean was 1.07 m s(-1) (95% CI: 1.01-1.13). The inspiratory SCR arrived at the fingers 1.26+/-0.09 s after the onset of chest wall movement. Electrical and auditory SCR onset latencies at the fingers were 1.60+/-0.03 and 1.75+/-0.04 s, respectively. Their CPTs were 140 and 160 ms, estimated from the electrical and auditory SCR onset latencies to the fingers. The CPT for inspiratory SCR was estimated to occur during the inspiratory CPT after the inspiratory decision and before chest movement. CONCLUSIONS In contrast to the SCR following an electrical or auditory stimulus, initiation of deep inspiratory SCR occurs before the inspiratory act, precluding any possible input from respiratory afferent receptors and implicating a central generator. SIGNIFICANCE This study provides new insights into the origin of the SCR following inspiration.
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Affiliation(s)
- C L Lim
- Department of Neurology (A4a), Westmead Hospital, Cnr Hawkesbury & Darcy Roads, Westmead, NSW 2145, Australia.
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11
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Goh VH, Tong TY, Lim CL, Low EC, Lee LK. Effects of one night of sleep deprivation on hormone profiles and performance efficiency. Mil Med 2001; 166:427-31. [PMID: 11370208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2023] Open
Abstract
This study examined the effects of one night of sleep deprivation on melatonin and cortisol profiles, as well as performance efficiency of military service members. Sleep intervention consisted of total lack of sleep (N = 7) or 8 hours of sleep (control group; N = 7) during the night. All parameters were measured at selected time intervals before (day 1), during (only in sleep-deprived individuals), and after (day 2) sleep intervention. Rotary pursuit scores and handgrip strength data were used as indices of psychomotor and physical performance, respectively. In sleep-deprived individuals, more salivary melatonin, but not cortisol, was secreted than in subjects who slept adequately. Significant increases in melatonin and cortisol were noted, especially at 1:30 p.m. on the day after nighttime sleep deprivation. In contrast, the tracking scores for rotary pursuit and grip strength among sleep-deprived and rested individuals were comparable. Across a normal working day (day 1), all parameters studied revealed time-specific fluctuations in both control and sleep-deprived groups. Irrespective of nighttime sleep schedule, the patterns of performance on day 2 differed from those on day 1. The tracking performance improved on day 2, whereas grip strength worsened, which may reflect inherent learning and muscle fatigue, respectively. During the night of sleep deprivation, performance declined. In conclusion, the present study showed that one night of sleep deprivation (8 hours) resulted in significant hormonal changes on the next afternoon but did not modify tracking and muscular strength performance.
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Affiliation(s)
- V H Goh
- Department of Obstetrics and Gynecology, National University of Singapore, National University Hospital, 5 Lower Kent Ridge Road, Singapore 119074
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12
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Goh VH, Tong TY, Lim CL, Low EC, Lee LK. Circadian disturbances after night-shift work onboard a naval ship. Mil Med 2000; 165:101-5. [PMID: 10709369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
The aim of the present study was to investigate how night duties can affect the circadian rhythms of military personnel working onboard a naval ship. Twenty individuals on a regular day-work schedule from 9:00 a.m. to 6:00 p.m. (serving as controls) and 40 individuals on night-shift duties participated in the study. Salivary melatonin and cortisol profiles were established within two 24-hour periods from 2-hour saliva samplings. Under the condition of abrupt shift in work/rest schedule, the majority of the navy officers (52%) retained their normal melatonin profiles. Twelve percent displayed a right phase shift in melatonin rhythm after night work. Nineteen percent exhibited distortions in the form of abnormal peaks or troughs, and 17% showed signs of disrupted rhythm in the form of low daytime levels of melatonin throughout the sampling period. No consistent relationship was found between the melatonin changes and various work stations of the ship. Prominent changes in the cortisol profile included unexpected peaks or troughs that may be related to the conditions that individuals were exposed to, i.e., high noise level in the engine room, as well as to performing intense tracking operations. The findings of this study (1) show the possible detrimental effects of shift duties on circadian rhythms, (2) highlight a wide interindividual variation in the manner in which the circadian systems respond to an abrupt phase shift in work/rest schedules, and (3) form the basis for further investigations into effective strategies to help military personnel cope with shift work, thereby maintaining health and high working standards while on duty.
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Affiliation(s)
- V H Goh
- Department of Obstetrics and Gynecology, National University of Singapore, National University Hospital, Singapore
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13
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Lazzaro I, Gordon E, Li W, Lim CL, Plahn M, Whitmont S, Clarke S, Barry RJ, Dosen A, Meares R. Simultaneous EEG and EDA measures in adolescent attention deficit hyperactivity disorder. Int J Psychophysiol 1999; 34:123-34. [PMID: 10576397 DOI: 10.1016/s0167-8760(99)00068-9] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Adolescent unmedicated ADHD males and age- and sex-matched normal control subjects were examined simultaneously using EEG and EDA measures in a resting eyes-open condition. ADHD adolescents showed increased absolute and relative Theta and Alpha1 activity, reduced relative Beta activity, reduced skin conductance level (SCL) and a reduced number of non-specific skin conductance responses (NS.SCRs) compared with the control subjects. Our findings indicate the continuation of increased slow wave activity in ADHD adolescents and the presence of a state of autonomic hypoarousal in this clinical group.
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Affiliation(s)
- I Lazzaro
- Department of Psychiatry, Westmead Hospital, Australia
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14
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Lim CL, Gordon E, Rennie C, Wright JJ, Bahramali H, Li WM, Clouston P, Morris JG. Dynamics of SCR, EEG, and ERP activity in an oddball paradigm with short interstimulus intervals. Psychophysiology 1999; 36:543-51. [PMID: 10442022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Studies of concurrent central, and autonomic activity using a conventional event-related potential (ERP) oddball paradigms, are considered useful in elucidating the relationship between central and autonomic responses, but the autonomic response tends to overlap. A new method was used to decompose and score overlapping skin conductance responses (SCR). This method enabled examination of dynamic relationships of phasic SCR, prestimulus electroencephalogram (EEG), and ERP to auditory target stimuli in 50 normal adults. SCR amplitude was negatively correlated to EEG and N200 amplitude. The SCR amplitude changes over time exhibited an exponential decline opposite to those of N200, alpha, and beta. All the fitted exponential functions had a time constant of 1-2 min. The findings suggest that a N200 component, active in the auditory sensory discrimination, is concomitant with the SCR. The narrow range of the time constant may provide a clue to the conjoint processes underlying central and autonomic adaptive functions.
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Affiliation(s)
- C L Lim
- Department of Neurology, University of Sydney, Australia.
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15
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Chung NK, Shabbir M, Lim CL. Cytokine levels in patients with previous heatstroke under heat stress. Mil Med 1999; 164:306-10. [PMID: 10226462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Abstract
We attempted to determine whether persons susceptible to heatstroke produced higher serum concentrations of interleukin-6, tumor necrosis factor-alpha, and interleukin-10 when subjected to heat stress. Nine patients with previous heatstroke and 21 matched controls were subjected to a heat-stress test (at 32 degrees C, 67% humidity, 900 W/m2 solar radiation, and wind speed of 2.5 m/s) for 60 minutes and rested at 24 degrees C for another 60 minutes in full battle gear. During the heat-stress test, blood was drawn at intervals of 0, 30, 60, and 120 minutes, and serum lipopolysaccharide, interleukin-6, tumor necrosis factor-alpha, and interleukin-10 concentrations were measured. Patients with previous heatstroke had a higher mean core temperature (0.6 degree C; p < 0.05) and sweated less (0.3 liters; p < 0.05). During the heat-stress test, the lipopolysaccharide levels were not increased and there was no difference in the serum cytokine concentrations between patients with previous heatstroke and controls. However, patients with previous heatstroke had higher absolute serum cytokine concentrations and poorer thermoregulatory response to heat stress in terms of core temperature and sweat loss.
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Affiliation(s)
- N K Chung
- Exercise Physiology Group, Defence Medical Research Institute, Republic of Singapore, Singapore
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16
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Abstract
The effects of age on late component (N100, P200, N200, and P300) event-related potentials (ERP) and reaction time (RT) were investigated in 50 normal subjects, 18 to 70 years of age. A conventional auditory oddball paradigm was employed. An equal number of subjects, as well as an equal number of males and females, were examined in each decade. There were no significant associations found between ERP amplitude and age. A significant positive correlation was found between age and N200/P300 latency. There were no significant effects of age on RT in the overall group. However, females had slower RT and decreased P200 and N200 amplitude as compared with males. Moreover, males had significant correlations between N200 latency and RT, whereas females showed significant correlations between P300 amplitude and RT. ERP/RT effects should be further explicated between gender, as well as across age.
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Affiliation(s)
- H Bahramali
- Cognitive Neuroscience Unit, Department of Psychological Medicine, Westmead Hospital, University of Sydney, Australia.
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17
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Lim CL, Gordon E, Harris A, Bahramali H, Li WM, Manor B, Rennie C. Electrodermal activity in schizophrenia: a quantitative study using a short interstimulus paradigm. Biol Psychiatry 1999; 45:127-35. [PMID: 9894584 DOI: 10.1016/s0006-3223(98)00056-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Electrodermal activity in response to short interstimulus interval (ISI) stimulation allows aspects of information processing to be examined, but such paradigms cause skin conductance responses (SCRs) to overlap. A signal decomposition method was developed and employed to score the overlapped SCRs. This is the first application of the method to the study of schizophrenia. METHODS Electrodermal activity of 30 medicated patients with schizophrenia and 50 normal controls was obtained using a conventional auditory oddball paradigm with an ISI of 1.3 sec. Tonic skin conductance level (SCL), phasic SCRs, SCR temporal dynamics, and a range of SCR variables in response to target tones were examined. RESULTS The schizophrenic group showed reduced response rate, proportion of responders, SCR amplitude, rise time, peak latency, and steady-state response amplitude, over the trial compared with controls. There were no between-group differences in SCL or SCR onset time. CONCLUSIONS The combined use of a conventional short ISI paradigm and the new SCR scoring method demonstrated new facets of electrodermal hyporeactivity in medicated patients with schizophrenia. The hyporeactivity could not be attributed to changes in tonic arousal or dysfunctions in peripheral sympathetic nerve conductance.
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Affiliation(s)
- C L Lim
- Department of Neurology, University of Sydney, Australia
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18
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Song EY, Lim CL, Lim MK. A comparison of maximum oxygen consumption, aerobic performance, and endurance in young and active male smokers and nonsmokers. Mil Med 1998; 163:770-4. [PMID: 9819539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
The purpose of this study was to compare 2.4-km running performance in 2,639 smoking (SM) and nonsmoking (NS) male conscripts aged 18 to 26 years. Maximum oxygen consumption (VO2max) and aerobic exercise endurance were also compared between SM and NS subjects (N = 156) stratified into various running performance bands. SM subjects ran significantly slower (10.59 +/- 1.17 minutes) than NS subjects (10.32 +/- 1.03 minutes) in the 2.4-km run test (p < 0.001). The mean VO2max of SM subjects (53.38 +/- 8.58 ml kg-1 min-1) was not significantly different from that of the NS subjects (54.42 +/- 7.82 ml kg-1 min-1) (p > 0.05). Exercise endurance time on the treadmill protocol (EXtm) was significantly longer in the NS group only among those who completed the 2.4-km run in < 9.01 minutes (p < 0.05). Maximum minute ventilation (VEmax) was also significantly higher in the NS group in the < 9.01-minute performance band. No other significant differences were found between SM and NS subjects in EXtm and VEmax. Mean maximum heart rate achieved during the tread-mill test ranged from 180 +/- 4 to 191 +/- 12 beats per minute in the SM group and from 183 +/- 5 to 188 +/- 19 beats per minute in the NS group. These were not significantly different (p > 0.05). In conclusion, smoking habit was shown to influence aerobic performance in the 2.4-km run, VEmax, and EXtm only during high-intensity aerobic exercise. VO2max was not influenced by smoking habit when aerobic performance was held constant.
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Affiliation(s)
- E Y Song
- Defence Medical Research Institute, AFPN 0051, Singapore
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19
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20
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Lagopoulos J, Gordon E, Barhamali H, Lim CL, Li WM, Clouston P, Morris JG. Dysfunctions of automatic (P300a) and controlled (P300b) processing in Parkinson's disease. Neurol Res 1998; 20:5-10. [PMID: 9471095 DOI: 10.1080/01616412.1998.11740476] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
P300 Event Related Potentials components (P300a and P300b) were investigated using an auditory oddball paradigm (with a button press response to target stimuli) in 15 Parkinson's disease patients and 50 normal controls whilst simultaneously measuring electrodermal activity. Cluster analysis showed that the first 10 target stimuli generated the largest skin conductance responses. The first 10 single-trial ERP epochs were therefore analysed as an ERP sub-average for each individual. The P300a component (associated with the automatic 'Orienting Reflex') was expected to be most prevalent in this sub-average (compared with sub-averages of subsequent blocks of 10 target stimuli). Twenty-nine out of 50 normal controls (58%) elicited a P300a in the first 10 target sub-average, compared with only 2 out of 15 Parkinson's disease subjects (13%). The conventional P300b component (associated with controlled processing) was found to be significantly delayed for all sub-averages for the Parkinson's disease group when compared with controls. These preliminary findings suggest a possible dysfunction in both automatic and controlled processing in this disorder.
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Affiliation(s)
- J Lagopoulos
- Department of Neurology, Westmead Hospital, Sydney, NSW, Australia
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21
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Abstract
Simultaneous measures of Event Related Potentials (ERP) and electrodermal activity (EDA) allow the delineation of ERPs that did, and did not, evoke an electrodermal 'Orienting Reflex' (OR). The OR is an automatic reflex invoked by novel or significant stimuli. Our group have developed a model to quantify electrodermal OR activity acquired in conventional late component ERP paradigms with short interstimulus intervals. Target late component (N100, P200, N200, P300) ERPs (acquired in an auditory oddball paradigm) and EDA was examined in 15 Parkinson's disease (PD) subjects and 50 normal controls. Single-trial target ERPs were averaged according to whether or not they elicited an electrodermal OR. Compared with controls, the PD group showed significantly decreased N100 and N200 amplitudes in the OR related ERPs ('Orienting ERPs'). These preliminary findings suggest that conventional late component ERPs can be delineated according to whether or not they evoked an OR. The 'orienting ERPs' in PD showed more significant disturbances compared with controls, than ERPs that did not evoke an OR.
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Affiliation(s)
- J Lagopoulos
- Department of Neurology, Westmead Hospital, Sydney, NSW, Australia
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22
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Lim CL, Chung KK, Hock LL. The effects of prolonged passive heat exposure and basic military training on thermoregulatory and cardiovascular responses in recruits from a tropical country. Mil Med 1997; 162:623-7. [PMID: 9290300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
This study investigates the effects of long-term passive heat exposure and a 16-week basic military training program on heat acclimatization. Thirty recruits were tested on the zero (T1), 2nd (T2), 6th (T3), and 16th (T4) weeks of the basic military training program. The trials involved 1 hour of marching on a treadmill at 5.5 km h-1, with a 5% gradient. The subjects wore their camouflage uniforms during the trials, with simulated combat loads. The trials were conducted in a climatic chamber programmed at 32 degrees C, 60% relative humidity, 900 Wm-2 of simulated solar radiation, and wind speed of 3 m s-1. There was no fluid replacement during the trials. Because only 9 subjects attended all the trials, the results presented are based on these subjects. No significant difference was found in mean skin temperature in all the four trials. Tympanic temperature was significantly reduced (p < 0.05) only at 20 minutes. Pairwise analysis was significant (p < 0.05) only between T1 (37.18 +/- 0.38 degrees C) and T4 (36.48 +/- 0.53 degrees C). Average body temperature was significantly different only at 10 and 60 minutes (p < 0.05). A significant pairwise difference (p < 0.05) was found only between T1 (36.61 +/- 0.33 degrees C) and T4 (36.07 +/- 0.46 degrees C) in 10 minutes. No pairwise difference was found at 60 minutes. Mean heart rate (HR) was significantly reduced during the 16 weeks at 10, 20, and 30 minutes. Mean HR at 10 minutes was reduced from 152.11 +/- 14.18 beats min-1 in T1 to 130.78 +/- 10.43 beats min-1 in T4 (p < 0.001). Mean HR at 20 and 30 minutes was reduced from 156.11 +/- 17.74 beats min-1 (T1) to 137.25 +/- 11.42 beats min-1 (T4) (p < 0.001), and from 157.14 +/- 15.77 beats min-1 (T1) to 146.11 +/- 12.64 beats min-1 (T4) (p < 0.05). There was no significant difference in sweat loss and mean sweat rate during the 16 weeks. This study concluded that long-term passive heat exposure was effective at inducing heat acclimatization in terms of tympanic temperature, average body temperature, mean skin temperature, sweat loss, and mean sweat rate, but not in terms of HR. Physical training was still necessary to induce further adaptation in HR. The limiting factor to task completion during the trials was physical fitness rather than beat fitness.
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Affiliation(s)
- C L Lim
- Singapore Armed Forces Soldier Performance Centre, Tanglin, Singapore
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23
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Abstract
Late component event related potentials (ERP) and concomitant electrodermal activity (EDA) measures of the orienting reflex (OR) were undertaken in 50 normal subjects. Our group recently developed a model to quantify electrodermal activity in conventional ERP paradigms (auditory oddball) with short interstimulus intervals (ISI). The method was used to classify the presence or absence of skin conductance response following each auditory target stimulus. Using a conventional paradigm in which data is traditionally averaged, single-trial target ERPs were sorted into those with a skin conductance response OR (ERP[+OR]) and those without (ERP[-OR]) an OR, and ERP sub-averages of the two groups were derived. The ERP(+OR) showed significantly larger P300 amplitudes and relatively earlier N200 and P300 latency than those of the ERP(-OR). These findings suggest that using concomitant SCR-ERP measures, separate ERP related processes can be determined, that are complementary to the traditional average measure.
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Affiliation(s)
- H Bahramali
- Department of Psychological Medicine, Westmead Hospital and The University of Sydney, NSW, Australia
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24
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Abstract
Overlapping phasic skin conductance responses (SCRs) obtained using short interstimulus interval (ISI) paradigms such as those employed in cognitive research, confound measurement of each discrete phasic SCR as well as the tonic skin conductance level (SCL). We report a method of resolving this problem using a modelling technique that takes advantage of the stereotyped nature of the within-subject SCR waveform. A four-parameter sigmoid-exponential SCR model that describes the entire response, was developed and extended to five-, six- and eight-parameter skin conductance (SC) models. These SC models were successfully curve-fitted to more than 60 SC segments, each containing one SCR or two overlapping SCRs on a sloping baseline obtained from 20 normal subjects. The SC segments were consequently decomposed into their components: the tail of the previous response, one or two SCRs and the SCL. The SCRs free of the complication of overlap were then quantified. The raw SCRs of the same data set were also measured using a standard method. The standard measurement showed a significant reduction of 15% in amplitude and 140 ms in peak latency compared to our method. The basic four SCR model parameters--onset time, rise time, decay time constant and gain--showed increasing inter-subject variability in that order. These SCR model parameters may be studied as variables in normal and patient groups and as indices of treatment response. This quantitative method also provides a means to assess the relationships between central and autonomic psychophysiologic measures.
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Affiliation(s)
- C L Lim
- Department of Neurology, Westmead Hospital, Australia.
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25
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Lee L, Kumar S, Kok WL, Lim CL. Effects of a pre-training conditioning programme on basic military training attrition rates. Ann Acad Med Singap 1997; 26:3-7. [PMID: 9140569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The medical attrition rates of 4 cohorts of recruits undergoing basic military training (BMT) were studied. They were grouped as follows: Group A (n = 3475), a mixture of fit and unfit recruits; Group B (n = 2081), consisting only of fit recruits; Group C (n = 940) comprising only unfit recruits who underwent a 4 to 6 weeks conditioning programme prior to being subjected to a similar 3-month BMT for all 3 groups and Group D (n = 2613) comprising unfit recruits who underwent an extended 4-month BMT. It was found that Group B [Relative risk (RR) = 0.26 95% confidence interval (CI) = 0.21, 0.33] and Group C (RR = 0.45 95% CI = 0.38, 0.62) had significantly lower medical attrition rates compared with Group A (RR = 1). Group D, however, did not show significantly lower attrition rates in spite of a more gradual training pace. When the unfit cohorts were compared, Group C (RR = 0.52 95% CI = 0.40, 0.67) had significantly lower attrition rates than Group D (RR = 1). The major cause of medical attrition in all groups was musculo-skeletal injuries sustained during training. Our results showed that a formal pre-training conditioning programme resulted in lower attrition during BMT and this reduction was more effective than training the recruits at a slower pace by extending the BMT by one month.
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Affiliation(s)
- L Lee
- HQ SAF Medical Corps, AFPN 1202, Singapore
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26
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Abstract
In the few reports where electrophysiologic techniques have been used to characterise stimulus-sensitive myoclonus in the setting of a parkinsonian syndrome, the origin of the myoclonus has usually been found to be cortical. We describe a patient with parkinsonism unresponsive to levodopa who had myoclonus that was both spontaneous and induced by somatosensory stimuli. In addition, autonomic symptoms and a marked sleep disturbance were present early in his illness. Results of electrophysiologic investigations including electromyography (EMG) studies, routine electroencephalography (EEG) recording, jerked locked back-averaging of EEG, and somatosensory evoked potentials were consistent with a brainstem origin for the myoclonic jerks. Following ipsilateral digital and supraorbital electrical stimulation, the earliest muscle activation occurred in the trapezius. An all-night sleep study showed frequent myoclonic jerks during sleep and markedly abnormal sleep architecture. We believe that this patient's myoclonus was related to pathologic changes in brainstem reticular nuclei that occurred as part of his disease process. To our knowledge, brainstem myoclonus has not been described as a feature of parkinsonian syndromes.
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Affiliation(s)
- P D Clouston
- Department of Neurology, Westmead Hospital, Sydney, Australia
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27
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Abstract
Electroencephalographic measures (EEG) and skin conductance level (SCL) respectively reflect cerebral cortical activity and sympathetic autonomic activity. Such central and autonomic activities associated with arousal generally have been studied separately, despite their potential to reflect complementary dimensions of reticular-thalamo-hypothalamo-cortical activating networks. In this study, we examined the relationship between cortical (19 EEG sites) and autonomic (SCL) activities recorded simultaneously in 10 normal adults. Two second pre-stimulus EEGs and SCLs were assessed from an habituation paradigm which presented 22 trains of 7 tones in an 'ignore' condition. The mean SCLs of the epochs across subjects showed an initial rise (sensitization) followed by an exponential decline (habituation). Although EEG associated with the tones did not demonstrate such a distinct profile, EEG total power and band powers (beta, alpha and theta) associated with the trains showed a systematic increasing response profile. In the group data the mean SCLs within trains showed a significant correlation with alpha and beta band powers. Finer EEG band analyses indicated that beta 3 at Fz and alpha 2 at Cz showed the strongest separate linear correlations with SCL. beta 3 and alpha 1 at Fz were found to jointly covary with SCL. The findings indicate a substantive relationship between measures of cerebral function and autonomic arousal.
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Affiliation(s)
- C L Lim
- Clinical Neurophysiology/Neurology Unit, Westmead Hospital, University of Sydney, Australia
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28
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Clouston PD, Lim CL, Sue C, Morris JG, Yiannikas C. Apomorphine can increase cutaneous inhibition of motor activity in Parkinson's disease. Electroencephalogr Clin Neurophysiol 1996; 101:8-15. [PMID: 8625879 DOI: 10.1016/0013-4694(95)00220-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We studied the effect of non-nociceptive ipsilateral digital stimulation on EMG recorded from a small hand muscle before and after the administration of subcutaneous apomorphine in 6 patients with Parkinson's disease. All were receiving the drug to control ¿on-off¿ fluctuations in motor performance. Averaged rectified EMG was recorded from tonically contracted abductor pollicis brevis (APB) following index finger stimulation using a brief stimulus train. In 5 patients motor evoked potentials (MEPs) were also recorded from APB during tonic contraction. A conditioning stimulus train was applied to the index finger at intervals between 15 and 65 msec prior to the transcranial magnetic stimulus. After apomorphine administration the patient group showed a significant increase in both EMG and MEP inhibition induced by digital stimulation. In patients with Parkinson's disease who have marked motor fluctuations, the inhibitory response of upper limb motor neurones to low level digital cutaneous stimulation can be altered by dopamine agonists.
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Affiliation(s)
- P D Clouston
- Motor Control and Movement Disorder Laboratory, Department of Neurology, Westmead Hospital, Sydney, NSW, Australia
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29
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Lim CL, Clouston P, Sheean G, Yiannikas C. The influence of voluntary EMG activity and click intensity on the vestibular click evoked myogenic potential. Muscle Nerve 1995; 18:1210-3. [PMID: 7659119 DOI: 10.1002/mus.880181021] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- C L Lim
- Neurology Department, Westmead Hospital, Sydney, NSW, Australia
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30
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Affiliation(s)
- C L Lim
- Department of Neurology, Westmead Hospital, Sydney, New South Wales, Australia
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31
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Lim CL, Lee LK. The effects of 20 weeks basic military training program on body composition, VO2max and aerobic fitness of obese recruits. J Sports Med Phys Fitness 1994; 34:271-8. [PMID: 7830391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Forty of the most obese recruits going through a 20 weeks Basic Military Training (BMT) program were selected from a cohort of 197 obese recruits. Their TBW, BF, FFW, VO2max, time taken to achieve VT (VTTime) and maximal heart rate (HRmax) were measured before, in the middle, and at the end of the program. The means for each of these variables measured in the 3 occasions were analysed for significant differences with the repeated measures analysis of variance. Variables that achieved significant difference were further analysed for pairwise difference with the post-hoc Tukey test. The critical value was set at p < 0.05. Mean TBW and BF decreased from 108.33 +/- 13.1 kg to 90.82 +/- 12.3 kg (p < 0.001), and 34.3 +/- 1.2% to 23.9 +/- 2.3% (p 0.001) respectively. Mean FW decreased from 37.4 +/- 4.8 kg to 22.0 +/- 4.5 kg (p < 0.001). FFW decreased slightly from a mean of 71.5 +/- 8.6 kg to 69.2 +/- 8.8 kg, which was not significantly different (p > 0.05). Mean VO2max increased from 28.1 +/- 6.3 ml.kg-1.min-1 to 32.1 +/- 5.1 ml.kg-1.min-1 (p < 0.001), and mean VTTime on similar exercise protocol increased from 13.3 +/- 2.7 minutes to 15.8 +/- 3.8 minutes (p < 0.001). Mean HRmax decreased from 183.5 +/- 12.1 beats.min-1 to 177.3 +/- 10.1 beats.min-1 (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- C L Lim
- Singapore Armed Forces, Soldier Performance Centre, Republic of Singapore
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32
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Abstract
A new method of assessing MEP facilitation using surface EMG under computer control is described. Transcranial magnetic stimulation with voluntary contraction at a value between 2 and 6% of maximal surface EMG activity produced responses with shortest latencies and largest amplitudes and power. No significant changes occurred when facilitation increased beyond this level. These results are similar to previously published studies using a force transducer, confirming the reliability of the system as an alternative method of monitoring voluntary contraction. The controlling system may potentially provide an easy, flexible, quantitative method of ensuring adequate, reproducible facilitation with minimum EMG interference for testing in a clinical setting.
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Affiliation(s)
- C L Lim
- Department of Neurophysiology, Westmead Hospital, Sydney, NSW, Australia
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33
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Abstract
Clinical and experimental evidence suggests a role for estrogen in the natural history of desmoid tumors (DT). Antiestrogen (tamoxifen) has been used empirically in some patients with significant tumor regression. To further investigate the mechanism of hormonal influence on desmoid tumors we initially characterized the cytosol estrogen receptor (ER) and antiestrogen binding sites (AEBS) in microsomal fractions of 15 cases of DT. Biopsy specimens were obtained from nine female and six male patients. ER assay was determined in cytosol (105,000 g) and the AEBS was detected in the microsomal fraction (7000 g for 20 min) by a DCC assay technique. ER was present in 33% of DT assayed (5/15), with equal incidence in males and females. Receptor content in female patients was higher than in male patients (26.52 +/- 16 vs 10.82 +/- 8.32 fmol/mg protein). Dissociation constant (Kd) range (0.44-3.97 nM) was well within the values seen in other estrogen target tissues. The AEBS were detected in 79% of the cases. The mean binding value was 236.7 +/- 170.2 fmol/mg protein. Kd values were between 0.39 and 5.97 nM. ER settled predominantly in the 4S region and AEBS settled in the 5-5.5S region in a 5-20% sucrose gradient. AEBS was detected in seven patients with negative ER. No correlation between ER and AEBS contents was observed. Competition studies revealed minimal binding with either DEX, DHT, R5020, and R1881, but partial binding with tamoxifen in cytosol and estradiol in microsomal fractions. ER and AEBS assays may be of prognostic significance in the natural history of these tumors.
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Lim CL. Successful transfer of "free" microvascular superficial temporal artery flap with no obvious venous drainage and use of leeches for reducing venous congestion: case report. Microsurgery 1986; 7:87-8. [PMID: 3724431 DOI: 10.1002/micr.1920070208] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A case is presented of "free" flap based on the frontal branch of the left superficial temporal artery and its surrounding soft tissues, without any proper vein for anastomosis, successfully transferred for eyebrow reconstruction. One can argue that this flap was a Wolfe graft. It probably was not for two reasons. First, "hairy Wolfe grafts" are always composite grafts with a thickness of 3-4 mm, as the base of the hair follicles lies in the subcutaneous tissue. Second, the edges of the flap were not sutured to the surrounding skin. Therefore, vascularization is unlikely from the surrounding skin and there was constant, definite oozing from the edge of this flap.
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35
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Abstract
The distribution of sweating on the face was studied in 31 patients with Horner's syndrome. In patients whose lesion was known to be distal to the bifurcation of the common carotid artery impairment of sweating was confined to the medial aspect of the forehead and side of the nose. In more proximal lesions loss of sweating involved the whole of one side of the face. Facial sweating was normal in 6 patients with avulsion injuries of the brachial plexus and in 2 patients with a lateral medullary syndrome. These findings suggest that the pattern of sweating in Horner's syndrome may be useful in some patients in localizing the site of the lesion.
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36
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Lim CL. Enuresis in children. Singapore Med J 1983; 24:363-6. [PMID: 6681492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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37
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Lim CL, Loh TG. Nerve conduction velocities and distal latencies in normal Malaysian subjects. Med J Malaysia 1978; 33:137-42. [PMID: 755164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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38
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Abstract
A 5-year-old child with subacute sclerosing panencephalitis had continuous involuntary ocular movements while awake. At this stage of illness, stereotyped periodic EEG complexes over the two hemispheres were asynchronous. Polygraphic studies showed three diffrent types of ocular movements, each apparently related to the degree of phase shift between the EEG complexes from the two hemispheres. The involuntary ocular movements in one direction were always preceded by periodic EEG complexes from the contralateral hemisphere. Overnight polygraphic studies revealed early disruption of non-rapid eye movement (NREM) sleep patterns and preservation of rapid eye movement (REM) sleep, even in a late stage of illness.
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39
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Abstract
A 27-year-old man with major motor and minor seizures showed focal epileptic discharges and electrical seizures triggered by eye convergence. Other voluntary ocular movements failed to evoke reflex epileptic discharges. Eye convergence triggered discharges even after the eyelids were strapped open with tapes and the pupillary and accommodation reflexes were temporarily paralyzed. This patient also showed pattern-sensitive focal epileptic discharges arising from the same area of the brain as those induced by eye convergence, but he was not photosensitive.
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40
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Abstract
One hundred and two patients suffering from seizures, with focal EEG signs (101 cases) and focal seizures but generalized EEG abnormalities (one case) were divided into tumour (twenty-one cases) and non-tumour (eighty-one cases) groups on the basis of contrast radiological studies. Retrospective analysis of various clinical data and EEG abnormalities, determined before the contrast radiological examinations, showed that the following were statistically significantly different between the two groups in favour of a tumoral aetiology for the seizures: age at onset of fits (greater than 20 years), presence of focal neurological signs and increased intracranial pressure, presence of focal unilateral delta waves without accompanying epileptic discharges, beta asymmetry between the cerebral hemispheres and hyperventilation-induced electrical seizures. A brain scan was a very useful screening test for the detection of a tumoral aetiology for seizures.
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Abstract
Opsoclonus and intention tremors of the body were seen transiently in a 20-year-old woman with postinfectious encephalopathy. Electro-oculograms showed multidirectional eye oscillations: oblique and disconjugate involuntary movements were commonly seen. The opsoclonus was triggered by both saccadic and nonsaccadic eye movements including those not concerned with visual fixation.
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