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133 results on '"Tan, S.K."'

14. Random and combinatorial mutagenesis for improved total production of secretory target protein in Escherichia coli

Author

Gonzalez-Perez, D., Ratcliffe, J., Tan, S.K., Wong, M.C.M., Yee, Y.P., Nyabadza, N., Xu, J.-H., Wong, T.S., and Tee, K.L.

Abstract

Signal peptides and secretory carrier proteins are commonly used to secrete heterologous recombinant protein in Gram-negative bacteria. The Escherichia coli osmotically-inducible protein Y (OsmY) is a carrier protein that secretes a target protein extracellularly, and we have previously applied it in the Bacterial Extracellular Protein Secretion System (BENNY) to accelerate directed evolution. In this study, we reported the first application of random and combinatorial mutagenesis on a carrier protein to enhance total secretory target protein production. After one round of random mutagenesis followed by combining the mutations found, OsmY(M3) (L6P, V43A, S154R, V191E) was identified as the best carrier protein. OsmY(M3) produced 3.1 ± 0.3 fold and 2.9 ± 0.8 fold more secretory Tfu0937 β-glucosidase than its wildtype counterpart in E. coli strains BL21(DE3) and C41(DE3), respectively. OsmY(M3) also produced more secretory Tfu0937 at different cultivation temperatures (37 °C, 30 °C and 25 °C) compared to the wildtype. Subcellular fractionation of the expressed protein confirmed the essential role of OsmY in protein secretion. Up to 80.8 ± 12.2% of total soluble protein was secreted after 15 h of cultivation. When fused to a red fluorescent protein or a lipase from Bacillus subtillis, OsmY(M3) also produced more secretory protein compared to the wildtype. In this study, OsmY(M3) variant improved the extracellular production of three proteins originating from diverse organisms and with diverse properties, clearly demonstrating its wide-ranging applications. The use of random and combinatorial mutagenesis on the carrier protein demonstrated in this work can also be further extended to evolve other signal peptides or carrier proteins for secretory protein production in E. coli.

Published
2021

15. Physical fitness of normal, stunted and overweight children 6-13 years in Oaxaca, Mexico

Author

Malina, R.M., Reyes, M.E. Pena, Tan, S.K., and Little, B.B.

Subjects
Exercise -- Health aspects, Obesity in children -- Risk factors -- Care and treatment -- Research, Food/cooking/nutrition, Health
Abstract

Background/Objective: The objective of this study is to compare the growth and physical fitness of normal, stunted and overweight/obese (owt/ob) Oaxaca children 6-13 years. Subjects/Methods: This study was a cross-sectional, included 688 school children (grades 1-3, 4-6), aged 6-13 years, from an indigenous rural community (n = 361) and colonia popular (n = 327) in Oaxaca, southern Mexico. Measurements: Anthropometry--weight, height, sitting height, limb circumferences, skinfolds. Derived--body mass index, sitting height/ height ratio, leg and step lengths, limb muscle areas, sum of skinfolds. Physical fitness--sit and reach, sit-ups, distance run, grip strength, standing long jump, 35 yard dash. Physical activity--steps to and from school, household chores, sports participation. Analysis: Normal--not stunted, not owt/ob; stunted--not owt/ob; and owt/ob--not stunted were compared with multivariate analysis of covariance controlling for age. Two children were stunted and owt/ob, and were excluded. Results: Age-adjusted means for body size, muscularity, adiposity and grip strength showed a gradient, owt/ob > normal > stunted in both sexes and grade levels (P Conclusion: Size, muscularity, fatness and strength differed significantly, owt/ob> normal> stunted, but owt/ob children had less strength per unit mass and poorer endurance. Normal and stunted children did not differ consistently in fitness. Physical activity and television time did not differ among the three groups. European Journal of Clinical Nutrition (2011) 65, 826-834; doi: 10.1038/ejcn.2011.44; published online 30 March 2011 Keywords: undernutrition; stunting; endurance; strength; flexibility; physical activity, Introduction A shift from high prevalence of chronic undernutrition and associated infectious/diarrheal diseases to high prevalence of chronic diseases associated with dietary change and reduced physical activity and increased overweight/obesity [...]

Published
2011
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19. Use of artificial neural networks as explicit finite difference operators

Author

Chua, Lloyd H.C. and Tan, S.K.

Subjects
Neural networks -- Usage, Numerical analysis, Neural network, Computers, Engineering and manufacturing industries, Science and technology
Abstract

Results of a numerical exercise, substituting a numerical operator by an artificial neural network (ANN) are presented in this paper. The numerical operator used is the explicit form of the finite difference (FD) scheme. The FD scheme was used to discretize the one-dimensional transport equation, which included both the advection and dispersion terms. Inputs to the ANN are the FD representation of the transport equation, and the concentration was designated as the output. Concentration values used for training the ANN were obtained from analytical solutions. The numerical operator was reconstructed from a back calculation of the weights of the ANN. Linear transfer functions were used for this purpose. The ANN was able to accurately recover the velocity used in the training data, but not the dispersion coefficient. This capability was improved when numerical dispersion was taken into account; however, it is limited to the condition: C/P < 0.5, where C is the Courant number and P, the Peclet number (i.e., the restriction imposed by the Neumann stability condition). CE Database subject headings: Neural networks; Numerical analysis; Finite differences; Dispersion.

Published
2005

21. Algorithms for burst rescheduling in WDM optical burst switching networks

Author

Tan, S.K., Mohan, G., and Chua, K.C.

Subjects
Internet, Burst mode -- Research, Computer networks -- Research, Information networks, Internet -- Research, Digital multiplexing -- Research, Multiplexing, Multichannel communication, Optical communications -- Research
Published
2003

26. Physicians' guideline adherence is associated with long-term heart failure mortality in outpatients with heart failure with reduced ejection fraction: the QUALIFY international registry

Author

Komajda, M. Schöpe, J. Wagenpfeil, S. Tavazzi, L. Böhm, M. Ponikowski, P. Anker, S.D. Filippatos, G.S. Cowie, M.R. Aleksanyan, A. Atayan, L. Avetisyan, A. Davtyan, N. Drambyan, M. Gevorgyan, K. Grigoryan, M. Hakobyan, Z. Hayrapetyan, H. Kocharyan, L. Kramarevskaya, T. Melqonyan, A. Muradyan, F. Nanyan, R. Ordyan, A. Ordyan, M. Piruzyan, A. Podosyan, G. Safaryan, K. Sargsyan, T. Sarkisyan, A. Sisakyan, H. Ter-Grigoryan, V. Ustyan, T. Alexopoulos, C. Amerena, J. Arstall, M. Ayres, B. Barron, G. Beltrame, J. Bou-Samra, J. Brown, M. Cross, D. Dwyer, N. Eccleston, N. Hare, D. Ho, B. Hopper, I. Jackson, B. Korczyk, D. Lattimore, J.D. Levendel, A. Macfadyen, R. Pandeli, V. Playford, D. Richardson, M. Senior, J.A. Shah, A. Shetty, P. Soward, A. Srivastava, P. Swale, M. Vogl, E. Wai, B. William, M. Worthington, A. Wright, S. Brunner, B. Fuhrmann, W. Horer, L. Maca, T. Nahler, A. Ortner, H. Racz, G. Scheibner, P. Sebald, C. Abdullayev, A. Abdullayev, R. Ahmadov, A. Alakbarov, E. Aliyev, F. Aliyev, F. Bakhshaliyev, A. Bakhshiyev, M. Dadashova, G. Dashdamirov, R. Faradjova, N. Guliyev, A. Guliyev, F. Guliyeva, S. Hajiyev, G. Ibrahimov, F. Imanov, G. Isayeva, A. Isayeva, M. Jabrailova, U. Jafarov, R. Jahangirov, T. Khalilov, A. Khalilov, S. Mehdiyev, S. Najafov, R. Samedova, H. Shahhuseynov, S. Yusifly, R. Yusifov, T. Zahidova, K. Zeynalov, A. Abdullatif, A. Al-Banna, R. Haiky, W. Husain, A. Jamsheer, A. Barbuk, O. Belskaya, M. Borodko, V. Kurlianskaya, A. Mackevich, S. Mankevich, N. Moroz-Vodolazhskaya, N. Ravtovich, O. Saevich, A. Troyanova, T. Chughtai, A. Johar, S. Luqman, N. Nair, T.C.-R. Deyoung, P. Ezekowitz, J. Frenette, M. Howlett, J. Huynh, T. Nguyen, V. Toma, M. Orenstein, T. Rinne, M.R.C. Virani, S. Zieroth, S. Ailiman, M. Cong, H. Ding, W. Dong, W. Dong, Y. Gao, C. Li, L. Li, Z. Liang, Y. Liu, X. Liu, S. Luo, S. Shi, H. Tian, Q. Wang, D. Wang, J. Wei, M. Wu, C. Xu, D. Yang, X. Yang, Z. Zhang, C. Zhang, Q. Zhang, Y. Zhang, R. Zheng, Y. Zhao, L. Zhou, J. Buch, P. Davidsen, F. Eiskjær, H. Bruun, N.E. Kragh-Thomsen, N.E. Franow, H. Køber, L. Korup, E. Madsen, B.K. Mikkelsen, K. Nielsen, K.A. Nørgaard, A. Refsgaard, J. Rickers, H. Kaiser, P. Sykulski, R. Zeuthen, E.L. El Fottoh, A.A. El Badry, M. El Hady, Y.A. El Kady, E. El Khatib, H. Fawzy, M. Hegazy, H. Salama, M.K. Mortada, A. Mostafa, T. Mwafy, A. Ossama, M. Samir, S. Seleem, M. Sobhy, B. Bregadze, G. Chelidze, K. Chumburidze, V. Jalabadze, K. Khabeishvili, G. Kiphiani, Z. Klimiashvili, Z. Kvitsiani, A. Mamatsashvili, M. Melia, I.M.A. Oragvelidze, T. Orjonikidze, S. Paposhvili, K. Petriashvili, S. Phaghava, Z. Shushania, M. Tsetskhladze, E. Tsinamdzgvishvili, B. Abdel-Qader, M. Al-Zoebi, A. Böhm, G. Bosch, R. Brune, S. Bunge, K. Dominick, K. Duda, S. Erdogan, A.E. Faber, G. Fach, C. Fechtrup, C. Frickel, S. Giokoglu, K. Haas, J. Hagenow, A. Haj-Yehia, A. Hansen, C. Hartung, W.M. Hauser, E.R. Hofmeister, A. Hohensee, H. Hüttemann, M. Keim, M. Krämer, A. Langwasser, K. Lodde, B.P. Lorch, G. Lüer, C. Müller, K. Placke, J. Plesch, B. Potolidis, L. Richter, F. Rieker, W.A. Schlichting, J. Stenzel, G. Theuer, J.D. Marcin, A. Warkentin, R. Wegner, M. Wilke, A. Agrafiotis, I. Aleksandridis, I. Farmakis, D. Giannakoulas, G. Karavidas, A. Lamprou, A. Ninios, V. Panagiotopoulos, K. Papadopoulos, K. Siachos, S. Dékány, M. Borbéy, A. Borsányi, T. Forster, T. Gavallér, H. Gyuricza, I. Heltai, K. Herczeg, B. HŐgye, M. Losonczi, I. Merkely, B. Metz, E. Muk, B. Nagy, K. Ökrös, M. Piry, K. Poós, G. Sárszegi, Z. Somogyi, T. Sziliczei-Németh, E. Tátrai, T. Zima, E. Zsigmond, A. Daly, C. Mahon, N. Meany, B. Abbdi, I. Awaysheh, R. Azouka, M. Hamoudeh, S. Nammas, A. Okkeh, O. Aimakova, G. Ismagulova, Z. Issabekova, A. Junusbekova, G.A. Koshumbayeva, K. Madaliyev, K. Mekebekova, D. Mukatova, A. Ospanova, G. Sadvakassova, G. Sunkarbekova, Z. Yegorova, Y. Zhangelova, S. Kim, K.H. Al-Mutairi, M. Gaber, Y. Ghali, I. Ghanem, A. Hafez, H. Haiba, M. Koushy, T. Mahmoud, A. Raafat, G. Sallam, M. Senousi, O. Soliman, M. Massih, T.A. Ali, S.A. Jaoude, S.A. Azzi, N. Badaoui, G. Bayeh, H. Beydoun, A. Chammas, E. Dib, H. Gebran, M. Ghanem, G. Haidar, H. Hamadeh, M. Hamoui, O. Hobeika, R. Jazra, C. Kabbani, S. Kadri, Z. Karanaminassian, R. Kassab, R. Kleit, M. Mansour, H. Mousallem, N. Semaan, C. Simonian, A. Sarkis, A. Succar, S. Zalloum, R. Zind, R. Anusauskiene, J. Grigaliuniene, A. Karaliute, R. Kavoliuniene, A. Kozlovaite, V. Miliuniene, D. Rinkuniene, D. Rudys, A. Stasaityte, D. Aziz, F.A.A. Rahim, A.A.A. Ahmad, R. Ahmadsah, S.H.K.A. Ang, C.C. Ang, S.H. Cham, Y.L. Chee, K.H. Chooi, K.C. Chu, C.M. Fam, T.L. Fong, A. Ismail, O. Ismail, J.R. Kamarulzaman, M.H. Kasim, S.S. Khiew, N.Z. Krishnan, C. Krishinan, S. Lau, G. Lee, L.Y. Liew, H.B. Lim, C.W. Mahendran, K. Dass, R.D.M. Mohamad, R. Arshad, M.K.M. Unit, H.M. Mustapha, Z. Ng, W.K. Ong, T.K. Oon, Y.Y. Ramli, A.W. Ramanathan, G.R.L. Ross, N.T. Said, A. Sarwar, M. Tan, E. Tan, S.K. Voon, C.Y. Yusoff, M.R. Abidin, H.A.Z. Chua, S.K. Yew, K.L. Amin, N.H.M. Kandiah, K. Chong, L.A. Mohamed, M.S. Lim, B.K. Koh, K.T. Low, D.W. Abdelkhirane, C. Allali, Y. Askour, M. Balafrej, K. Bendagha, N. Bendriss, L. Benjelloun, H. Chaib, A. Cherradi, G. Cherti, M. Chtioui, M. El Belghiti, A.R. Fihri, O.F. Habbal, R. El Hattaoui, M. Khatouri, A. Kheyi, J. Kriem, J. Soufiane, N. Soufiani, A. Zaimi, S. Adamczyk-Kot, D. Barg, Z. Bartkowiak, R. Braciszewicz, W. Czajkowska, E. Dudek-Niechciał, M. Grzelakowski, P. Jarosik, Z. Jerzykowska, O. Koprowski, P. Krysiak, W. Łajkowski, Z. Ziemlewska-Krawczyk, E. Lelonek, M. Lewicka, E. Płonka, J. Sadowski, J. StĘpieŃ-Adamczewska, V. Szponar, J. WrzesiŃski, K. Brito, D.A. Araújo, I. Figueiredo, J.P.A. Campelo, M.B. Sardinha, P.M.B. Fernando, P. de Brito Domingues Sanches Peres de Noronha, M.A. Baptista, S.B.C. Cardoso Pinto, J.P. Piçarra, B.M.C. Farto e Abreu, P. da Fonseca, M.C.F.G. Soares, A.I.C.G.O. Resende, J.D.A. Durão, D.L. Nascimento, A.I.F.V. Bernardes, E.L.M.O. Marques, F. Ramos, M.A.N. Sargento, L.J.M. dos Santos, J.P.F. Raimundo, A. da Luz Ventosa, A.M.S. Sarmento, P. Aguiar, C.M.T. Ahmed, E. Al-Suwaidi, J. Al Dabdoob, W. Badr, A. Gomaa, M. Albu, M. Antohi, I. Apavaloaei, C. Ardelean, A. Badea, G. Bicescu, G. Blaj, C. Bogdan, L. Bucatanschi, M. Buzea, A. Calarasu, V. Catinean, S. Christodorescu, R. Cocoi, D. Costache, L. Cretu, D. Crisu, D. Dima-Cozma, C. Dumitrescu, S. Enache, V. Firastrau, V. Frigy, A. Gherghina, A. Girbea, S. Gutu, A. Horovitz, M. Hortopan, G. Istratoaie, O. Jianu, C. Jinga, L. Lighezan, D. Luka, A. Magheru, S. Mercea, D. Miklos, K. Moga, R. Oprea, N. Paraschiv, D.M. Pop, D. Rusu, R. Sirbu, I. Socoteanu, E. Stanciulescu, G. Suteu, A. Tetiu, O. Traistaru, A. Tudoran, M. Turiceanu, M.C. Viinkler, L. Adonina, E. Akinina, S. Alferov, P. Arkhipov, M. Aroutunov, G. Babkin, A. Barbashina, T. Bochkareva, J. Boldueva, S. Bukhonkina, J. Chumakova, S.G. Fayans, I. Furmenko, G. Galyavich, A. Grinstein, Y. Klein, G. Kastanayan, A. Kazachkova, T. Korolev, S. Koshelskaya, O. Kosmacheva, E. Koziolova, N. Kuimov, A. Kushnarenko, N. Lebedev, P. Matushin, G. Mineeva, E. Motylev, I. Nedbaykin, A. Nevzorova, V. Rachkova, S. Rebrov, A. Reznik, I. Saiganov, S. Sayfutdinov, R. Schekotov, V. Serdechnaya, E. Shalaev, S. Shtegman, O. Sitnikova, M. Smolenskaya, O. Sulimov, V. Tarlovskaya, E. Temnikova, E. Timonin, D. Tolstov, S. Uskatch, T. Ustyuzhanin, V. Valeeva, R. Vasyuk, Y. Viktorova, I. Yakushin, S. Zadionchenko, V. Zateischikov, D. Zhirov, I. Bollová, D. Dulková, K. Fazekaš, F. Hermel, I. KŇazeje, M. NedĚĽová, I. Nociar, J. Procházka, L. Pundová, L. Slanina, M. Varga, I. Almenar, L. Beltrán, P. Cobo, M. Delgado, J. Enjuanes, C. Garrido, I. Gómez, M.A. Manito, N. Marzal, D. Murga, N. Ocampo, M. Pérez, J. Sánchez, I. Buakhamsri, A. Leemasawat, K. Kanoksilp, A. Kiatchoosakun, S. Phrommintikul, A. Porapakkham, P. Rodprasert, S. Senthong, V. Wongcharoen, W. Wongwantanee, S. Bahadir, H. Emül, A. Gokce, M. Gurcagan, A. Kaya, O.K. Keser, A. Pinar, P. Taș, M.H. Tosun, H.B. Yazlar, A.S. Yilmaz, S. Yuksel, Y. Bagriy, A. Ivchyna, N. Lyashenko, A. Matviychuk, N. Shchukina, O. Tkach, N. Tseluyko, V. Vasylieva, L. Abdallah, A. Agrawal, A. Basleeb, F. Bazargani, N. Hatou, E. Al Kaddour, A.R. Al Kasser, M. Al Mulla, A. Radaideh, G. Salustri, A. on behalf of the QUALIFY Investigators

Abstract

Background: Physicians' adherence to guideline-recommended therapy is associated with short-term clinical outcomes in heart failure (HF) with reduced ejection fraction (HFrEF). However, its impact on longer-term outcomes is poorly documented. Here, we present results from the 18-month follow-up of the QUALIFY registry. Methods and results: Data at 18 months were available for 6118 ambulatory HFrEF patients from this international prospective observational survey. Adherence was measured as a continuous variable, ranging from 0 to 1, and was assessed for five classes of recommended HF medications and dosages. Most deaths were cardiovascular (CV) (228/394) and HF-related (191/394) and the same was true for unplanned hospitalizations (1175 CV and 861 HF-related hospitalizations, out of a total of 1541). According to univariable analysis, CV and HF deaths were significantly associated with physician adherence to guidelines. In multivariable analysis, HF death was associated with adherence level [subdistribution hazard ratio (SHR) 0.93, 95% confidence interval (CI) 0.87–0.99 per 0.1 unit adherence level increase; P = 0.034] as was composite of HF hospitalization or CV death (SHR 0.97, 95% CI 0.94–0.99 per 0.1 unit adherence level increase; P = 0.043), whereas unplanned all-cause, CV or HF hospitalizations were not (all-cause: SHR 0.99, 95% CI 0.9–1.02; CV: SHR 0.98, 95% CI 0.96–1.01; and HF: SHR 0.99, 95% CI 0.96–1.02 per 0.1 unit change in adherence score; P = 0.52, P = 0.2, and P = 0.4, respectively). Conclusion: These results suggest that physicians' adherence to guideline-recommended HF therapies is associated with improved outcomes in HFrEF. Practical strategies should be established to improve physicians' adherence to guidelines. © 2019 The Authors. European Journal of Heart Failure © 2019 European Society of Cardiology

Published
2019

30. Combination Therapy Strategy of Quorum Quenching Enzyme and Quorum Sensing Inhibitor in Suppressing Multiple Quorum Sensing Pathways of P. aeruginosa

Author

Fong, J., Zhang, C., Yang, R., Boo, Z.Z., Tan, S.K., Nielsen, T.E., Givskov, M., Liu, X.-W., Bin, W., Su, Haibin, Yang, L., Fong, J., Zhang, C., Yang, R., Boo, Z.Z., Tan, S.K., Nielsen, T.E., Givskov, M., Liu, X.-W., Bin, W., Su, Haibin, and Yang, L.

Abstract

The threat of antibiotic resistant bacteria has called for alternative antimicrobial strategies that would mitigate the increase of classical resistance mechanism. Many bacteria employ quorum sensing (QS) to govern the production of virulence factors and formation of drug-resistant biofilms. Targeting the mechanism of QS has proven to be a functional alternative to conventional antibiotic control of infections. However, the presence of multiple QS systems in individual bacterial species poses a challenge to this approach. Quorum sensing inhibitors (QSI) and quorum quenching enzymes (QQE) have been both investigated for their QS interfering capabilities. Here, we first simulated the combination effect of QQE and QSI in blocking bacterial QS. The effect was next validated by experiments using AiiA as QQE and G1 as QSI on Pseudomonas aeruginosa LasR/I and RhlR/I QS circuits. Combination of QQE and QSI almost completely blocked the P. aeruginosa las and rhl QS systems. Our findings provide a potential chemical biology application strategy for bacterial QS disruption. © 2018 The Author(s).

Published
2018

34. Synergy of Quorum Quenching Enzyme and Quorum Sensing Inhibitor in Inhibiting P.aeruginosa Quorum Sensing

Author

Fong, J., Zhang, C., Yang, R., Boo, Z.Z., Tan, S.K., Nielsen, T.E., Givskov, M., Wu, B., Su, H., Yang, L., Fong, J., Zhang, C., Yang, R., Boo, Z.Z., Tan, S.K., Nielsen, T.E., Givskov, M., Wu, B., Su, H., and Yang, L.

Abstract

The threat of antibiotic resistant bacteria has called for alternative antimicrobial strategies that would mitigate the increase of classical resistance mechanism. Many bacteria employ quorum sensing (QS) to govern the production of virulence genes and formation of drug-resistance biofilms. Blocking QS mechanisms have proven to be a functional alternative to conventional antibiotic control of infections. The concepts of quorum sensing inhibitors (QSI) and quorum quenching enzymes (QQ) have been investigated separately. In this study however, we simulated the synergistic effect of QQ and QSI in blocking bacterial QS. This effect was validated by experiments using AiiA and G1 as QQ and QSI respectively on Pseudomonas aeruginosa LasR/I and RhlR/I QS circuits. The combination of a QQ and a QSI almost completely blocked the P. aeruginosa QS las and rhl system. Our findings provided a potential application strategy for bacterial QS disruption.

Published
2017

35. Mutational analysis of BRCA1 in familial breast cancer in Malaysia

Author

Balraj, P., Khoo, A.S.B., Choy, Y.S., Tan, S.K., Tan, J.A.M.A., Abdullah, H., and Yip, C.H.

Subjects
Human genetics -- Research, Human chromosome abnormalities -- Research, Genetic disorders -- Research, Familial diseases -- Research, Breast cancer -- Genetic aspects, Genetic screening -- Economic aspects, Gel electrophoresis -- Usage, Genetic polymorphisms -- Identification and classification, Biological sciences
Published
2001

39. Validation of actigraphy for determining sleep and wake in children with sleep disordered breathing.

Author

Tan S.K., Horne R.S.C., Davey M.J., Hyde M., Verginis N., O'Driscoll D.M., Binette S., Galang C., Tan S.K., Horne R.S.C., Davey M.J., Hyde M., Verginis N., O'Driscoll D.M., Binette S., and Galang C.

Abstract

There have been limited studies of the validation of actigraphy for the determination of sleep and wake in children and in this study we aimed to compare wrist actigraphy with polysomnography (PSG). We studied 45 children (29 M/16 F), aged between 1 and 12 years (5.8 +/- 2.7 years, mean +/- SD). Actigraphic data were collected during standard overnight PSG. Data from the actiwatch were analysed over four separate activity threshold settings (low, medium, high, auto). Actigraphic data were compared epoch-by-epoch with the matching PSG. Sleep time was not different from PSG values for the low or auto activity thresholds, but was significantly less on the medium and high activity thresholds (P < 0.05). In contrast, the low and auto activity thresholds significantly underestimated wake time (P < 0.05), whilst that recorded on the medium and high activity thresholds were not different to PSG values. Agreement rates across the thresholds were all high ranging from 85.1% to 88.6%. Predictive value for sleep and sensitivity were also high with values ranging from 91.6% to 94.9% and 90.1% to 97.7%, respectively. In contrast, predictive value for wake and specificity were low ranging between 46.7-65.6% and 39.4-68.9%, respectively. There was no effect of subject age, OAHI or PSG arousal index on AR for any of the activity thresholds. We conclude that actigraphy is a reliable method for determining sleep in children when compared against PSG. Actigraphy may be a useful tool in paediatric sleep clinics and research. © 2007 European Sleep Research Society.

Published
2012

44. Dynamic analysis of a slender body of revolution berthing to a wall

Author

Wang, Q.X. and Tan, S.K.

Subjects
Fluid dynamics -- Research, Engineering and manufacturing industries, Science and technology
Abstract

A slender body of revolution berthing to a wall is studied by extending the classical slender body theory. This topic is of practical importance for a ship berthing to a quay wall. The flow problem is solved analytically using the method of matched asymptotic expansions. The lateral force and yaw moment on the body are obtained in a closed form too. The translation and yawing of the body are modeled using the second Newton law and coupled with the flow induced. Numerical analyses are performed for the dynamic lateral translation and yawing of a slender spheroid, while its horizontal translation parallel to the wall is prescribed at zero speed, constant speed, and time varying speed, respectively. The analysis reveals the interesting dynamic features of the translation and yawing of the body in terms of the forward speed and starting angle of yaw of the body. [DOI: 10.1115/1.3026727] Keywords: ship berthing, slender body theory, matched asymptotic expansions, conformal mapping, dynamic motion, potential flow theory

Published
2009

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