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Assessment of Sleep Deprivation and Fatigue Among Chemical Transportation Drivers in Chonburi, Thailand

  • Phatrabuddha, Nantaporn;Yingratanasuk, Tanongsak;Rotwannasin, Piti;Jaidee, Wanlop;Krajaiklang, Narin
    • Safety and Health at Work
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    • v.9 no.2
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    • pp.159-163
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    • 2018
  • Background: Fatigue and sleepiness are inter-related and common among road transport drivers. In this study, sleep deprivation and fatigue among chemical transportation drivers were examined. Methods: A cross-sectional study surveying 107 drivers from three hazardous types of chemical production and transportation industries (nonflammable gases, flammable gases, and flammable liquids) was conducted. Data on sleep deprivation were collected using questionnaires of the Stanford Sleeping Scale and the Groningen Sleep Quality Scale. Fatigue was assessed using an interview questionnaire and a flicker fusion instrument. Results: Chemical drivers had a mean sleeping scale (Stanford Sleeping Scale) of 1.98 (standard deviation 1.00) and had a mean score of 1.89 (standard deviation 2.06) on the Groningen Sleep Quality Scale. High-risk drivers had higher scores in both the Stanford Sleeping Scale and the Groningen Sleep Quality Scale with a mean score of 2.59 and 4.62, respectively, and those differences reached statistical significance (p < 0.05). The prevalence of fatigue, as assessed through a critical flicker fusion analyzer, subjective fatigue question, and either of the instruments, was 32.32%, 16.16%, and 43.43%, respectively. Drivers who slept <7 hours and had poor sleep quality were found to have more fatigue than those who slept enough and well. Drivers who had a more sleepiness score resulted in significantly more objective fatigue than those who had a less sleepiness score. Conclusion: Sleep quality and sleeping hour can affect a driver's fatigue. Optimization of work-rest model should be considered to improve productivity, driver retention, and road safety.

Overexpression, Purification, and Characterization of the Herpes Simplex Virus-1 DNA Polymerase-UL42 Protein Complex

  • Song, Byeong-Doo;Lehman, I. Robert
    • BMB Reports
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    • v.31 no.6
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    • pp.585-589
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    • 1998
  • The herpes simplex virus type-1 (HSV-1)-encoded DNA polymerase consists of two subunits, the products of the UL30 and UL42 genes. UL30 and UL42 were coexpressed in Sf9 cells infected with recombinant baculoviruses carrying the two genes. The UL30 and UL42 gene products remained tightly associated throughout the purification, which led to a near homogeneous heterodimer composed of the DNA polymerase and UL42 protein. The DNA polymerase-UL42 protein heterodimer, purified from the recombinant baculovirus-infected Sf9 cells, showed the same high degree of processivity of deoxynucleotide polymerization as the enzyme purified from the HSV-1 infected primate cells. Like the latter, it contained a 3'-5' exonuclease activity that specifically hydrolyzes an incorrectly matched nucleotide at the 3' terminus of a primer, thereby contributing to the fidelity of DNA replication.

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Structure of Water Molecules inside Nanotubes with Varying Hydrophobicity Using Mole cular Dynamics Simulation (분자동역학 기법을 이용한 나노튜브의 소수성 또는 친수성에 의한 내부 물 분자의 구조 연구)

  • Kim, Dae-Joong;Wangperawong, Artit;Darve, Eric
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03b
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    • pp.660-661
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    • 2008
  • Nanotubes fabricated with diverse materials show different hydrophobic properties. The hydrophobic property is one of key properties for possible applications to ion channels due to their affinity. This study focuses on the structures of water molecules inside nanotubes with varying hydrophobicity using molecular dynamics simulation. Hydrophobicity here is determined by varying the attraction term in Lennard-Jones potential. The number of water molecules inside hydrophilic nanotubes increase, as expected, and their mobilities also increase. This trend is rather discrete with increasing number of water molecules and this discreteness is attributed to hydrogen bond. We plan to perform energy analysis to understand these structural results.

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Biocreative Alveolar Molding Plate Treatment (BioAMP) for neonatal unilateral cleft lip and palate with excessively wide alveolar cleft and maxillary arch width

  • HyeRan Choo;HyoWon Ahn
    • The korean journal of orthodontics
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    • v.54 no.1
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    • pp.69-73
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    • 2024
  • Since its inception in Europe in the 1950s, alveolar molding treatment for neonates with complete cleft lip and palate has undergone significant evolution in both design and application methodology, demonstrating effectiveness in normalizing the alveolar cleft and nasal shape. However, excessively wide alveolar clefts accompanied by disproportionately wide total maxillary arch pose significant challenges when utilizing conventional alveolar molding methods involving cyclical adding and grinding of acrylic on molding plates. The current report introduces a novel alveolar molding method named Biocreative Alveolar Molding Plate Treatment (BioAMP), which can normalize the maxillary alveolar cleft and arch shape without laborious conventional acrylic procedures. BioAMP sets the target arch form and provides unrestricted space for natural growth of the maxillary alveolar bones while systematically reducing the total maxillary arch width in precise increments. Two exemplary cases are presented as proof-of-concept, showcasing the clinical innovation of BioAMP.

Hybrid Endovascular Repair for Type I Endoleak after Stent Grafting of Chronic Stanford Type B Aortic Dissection (만성 Stanford B형 대동맥 박리로 하행 대동맥 스텐트 도관 삽입술 후 발생한 제I형 Endoleak의 치료에 시행한 Hybrid 혈관내 술식)

  • Kim, Kwan-Wook;Cho, Sang-Ho;Shim, Won-Heum;Youn, Young-Nam
    • Journal of Chest Surgery
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    • v.43 no.4
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    • pp.428-432
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    • 2010
  • A 67 years old male patient was admitted with back pain that had recurred from 6 months previously. Eleven years previously, he underwent stent grafting at the descending thoracic aorta for a chronic Stanford type B aortic dissection. The preoperative computed tomography showed aortic dissection from the origin of the left subclavian artery to the bifurcation of the abdominal aorta, and there was a type I endoleak at the proximal portion of the stent graft and aneurysmal dilatation of the descending aorta. A hybrid endovascular repair was successfully performed, and this involved debranching and rerouting the aortic arch vessels under extracorporeal cardiopulmonary bypass and then this was followed 13 days later by stenting in the ascending aorta, the aortic arch and the descending aorta. The postoperative computed tomography showed complete exclusion of the type I endoleak. After discharge, he has been followed up for 8 months without any problems.

The Changes in Range of Motion after a Lumbar Spinal Arthroplasty with Charite$^{TM}$ in the Human Cadaveric Spine under Physiologic Compressive Follower Preload: A Comparative Study between Load Control Protocol and Hybrid Protocol

  • Kim, Se-Hoon;Chang, Ung-Kyu;Chang, Jae-Chil;Chun, Kwon-Soo;Lim, T. Jesse;Kim, Daniel H.
    • Journal of Korean Neurosurgical Society
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    • v.46 no.2
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    • pp.144-151
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    • 2009
  • Objective: To compare two testing protocols for evaluating range of motion (ROM) changes in the preloaded cadaveric spines implanted with a mobile core type Charite$^{TM}$ lumbar artificial disc. Methods: Using five human cadaveric lumbosacral spines (L2-S2), baseline ROMs were measured with a bending moment of 8 Nm for all motion modes (flexion/extension, lateral bending, and axial rotation) in intact spine. The ROM was tracked using a video-based motion-capturing system. After the Charite$^{TM}$ disc was implanted at the L4-L5 level, the measurement was repeated using two different methods: 1) loading up to 8 Nm with the compressive follower preload as in testing the intact spine (Load control protocol), 2) loading in displacement control until the total ROM of L2-S2 matches that when the intact spine was loaded under load control (Hybrid protocol). The comparison between the data of each protocol was performed. Results: The ROMs of the L4-L5 arthroplasty level were increased in all test modalities (p < 0.05 in bending and rotation) under both load and hybrid protocols. At the adjacent segments, the ROMs were increased in all modes except flexion under load control protocol. Under hybrid protocol, the adjacent segments demonstrated decreased ROMs in all modalities except extension at the inferior segment. Statistical significance between load and hybrid protocols was observed during bending and rotation at the operative and adjacent levels (p< 0.05). Conclusion: In hybrid protocol, the Charite$^{TM}$ disc provided a relatively better restoration of ROM, than in the load control protocol, reproducing clinical observations in terms of motion following surgery.

Blossom smart expander technology for tissue expander-based breast reconstruction facilitates shorter duration to full expansion: A pilot study

  • Choi, Youna K.;Rochlin, Danielle H.;Nguyen, Dung H.
    • Archives of Plastic Surgery
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    • v.47 no.5
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    • pp.419-427
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    • 2020
  • Background This study evaluated the Blossom system, an innovative self-filling, rate-controlled, pressure-responsive saline tissue expander (TE) system. We investigated the feasibility of utilizing this technology to facilitate implant-based and combined flap with implant-based breast reconstruction in comparison to conventional tissue expansion. Methods In this prospective, single-center, single-surgeon pilot study, participants underwent either implant-based breast reconstruction or a combination of autologous flap and implantbased breast reconstruction. Outcome measures included time to full expansion, complications, total expansion volume, and pain scores. Results Fourteen patients (TEs; n=22), were included in this study. The mean time to full expansion was 13.4 days (standard error of the mean [SEM], 1.3 days) in the combination group and 11.7 days (SEM, 1.4 days) in the implant group (P=0.78). The overall major complication rate was 4.5% (n=1). No statistically significant differences were found in the complication rate between the combination group and the implant group. The maximum patient-reported pain scores during the expansion process were low, but were significantly higher in the combination group (mean, 2.00±0.09) than in the implant group (mean, 0.29±0.25; P=0.005). Conclusions The reported average duration for conventional subcutaneous TE expansion is 79.4 days, but this pilot study using the Blossom system achieved an average expansion duration of less than 14 days in both groups. The Blossom system may accommodate single-stage breast reconstruction. The overall complication rate of this study was 4.5%, which is promising compared to the reported complication rates of two-stage breast reconstruction with TEs (20%-45%).

Correlation of response spectral values in Japanese ground motions

  • Jayaram, Nirmal;Baker, Jack W.;Okano, Hajime;Ishida, Hiroshi;McCann, Martin W. Jr.;Mihara, Yoshinori
    • Earthquakes and Structures
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    • v.2 no.4
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    • pp.357-376
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    • 2011
  • Ground motion models predict the mean and standard deviation of the logarithm of spectral acceleration, as a function of predictor variables such as earthquake magnitude, distance and site condition. Such models have been developed for a variety of seismic environments throughout the world. Some calculations, such as the Conditional Mean Spectrum calculation, use this information but additionally require knowledge of correlation coefficients between logarithmic spectral acceleration values at multiple periods. Such correlation predictions have, to date, been developed primarily from data recorded in the Western United States from active shallow crustal earthquakes. This paper describes results from a study of spectral acceleration correlations from Japanese earthquake ground motion data that includes both crustal and subduction zone earthquakes. Comparisons are made between estimated correlations for Japanese response spectral ordinates and correlation estimates developed from Western United States ground motion data. The effect of ground motion model, earthquake source mechanism, seismic zone, site conditions, and source to site distance on estimated correlations is evaluated and discussed. Confidence intervals on these correlation estimates are introduced, to aid in identifying statistically significant differences in correlations among the factors considered. Observed general trends in correlation are similar to previous studies, with the exception of correlation of spectral accelerations between orthogonal components, which is seen to be higher here than previously observed. Some differences in correlations between earthquake source zones and earthquake mechanisms are observed, and so tables of correlations coefficients for each specific case are provided.

Subjective Measures of Operator Status in Surface Transportation: h Critical Review and Recommendations for Application (지상 교통에 있어서 운전자 상태의 주관적 척도: 비판적 고찰 및 응용을 위한 제언)

  • Heidi D. Howarth;Sohn, Young-Woo
    • Science of Emotion and Sensibility
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    • v.5 no.4
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    • pp.11-32
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    • 2002
  • This article evaluates the existing subjective measures that have been utilized in surface transportation to assess various aspects of operator status such as fatigue, sleepiness, arousal, mood, etc. Specifically, the representative six subjective instruments - Epworth Sleepiness Scale, Karolinska Sleepiness Scale, Pearson and Byars Fatigue Checklist, Stanford Sleepiness Scale, Stress-Arousal Checklist, and NPRU Mood Scale - are compared and contrasted in terms of reliability, . validity, sensitivity, and appropriateness for application. Recommendations for application of the subjective measures in surface transportation are discussed.

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