• Title/Summary/Keyword: London

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Role of London Energy in Determining the C-Dimensions of Phyllosilicates (층상 규산염광물 C-축 결정에 있어서의 런던에너지 역할)

  • 유재영
    • Journal of the Mineralogical Society of Korea
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    • v.3 no.2
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    • pp.89-97
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    • 1990
  • To examine how London energy controls the c-dimensions of phyllosilicates, London energy, as well as Coulomb and Pauli repulstion energy was calculated as a function of d(001) for 1M and d(002) for 2M 1 phyllosilicates. London and Pauli repulstion energy calcualtion use a direct interaction calculation method and Coulomb energy calculation adopts Fourier synthesis method. The energy calculations show that Coulmb and Pauli repulsion energy dominantly control the c-dimensions of phyllosilicates having the interlayer cationss, i.e., the layer charges. On the other hand, if phyllosilicates have no interlayer cations, London energy is solely responsible for holding the layers and maintain the c-dimensions. The significance of London energy in determining the c-dimensions of phyllosislicates de-creases as the layer charge increases. When the layer charge is lower than one equivalent on the basis of Oη(OH)2 formula, London energy plays an important role in determing the c-dimensions. however, if the layer charge is higher than one equivalent, London energy becomes insignifi-cant in determining the c-dimension.

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Recycling of flap pedicle in complex lower extremity reconstruction: A proof of free muscle flap neovascularization

  • Pafitanis, Georgios;Vris, Alexandros;Reissis, Dimitris;Sadri, Amir;Alamouti, Reza;Myers, Simon;Sadigh, Parviz
    • Archives of Plastic Surgery
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    • v.47 no.6
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    • pp.619-621
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    • 2020
  • This article portrays the authors' clinical experience of a complex case of lower extremity reconstruction using a recycled pedicle from 10 years old free latissimus dorsi musculocutaneous flap to supply a new free anterolateral thigh flap for proximal tibia wound defect reconstruction. It provides clinical evidence that muscle neovascularization occurs and supports the dogma peripheral tissue neovascularization. This case stipulates that recycling of pedicle is feasible, when used with appropriate strategy and safety and also provides evidence for the long-term survival of greater saphenous vein grafts in lower extremity reconstruction.

A Study on the Sustainable Characteristics of the London City Hall (런던 시청사의 지속가능적 특성에 관한 연구)

  • Chung, Tae-Yong
    • Korean Institute of Interior Design Journal
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    • v.20 no.5
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    • pp.3-12
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    • 2011
  • The purpose of this study is to analyze the sustainable characteristics of London city hall designed by Norman Foster. The most important part of sustainable architecture might be the energy reduction including minimizing CO$_2$ emission but social and economical aspects of sustainability should not be neglected. London City Hall as a successful example of sustainable architecture depends its success on the harmony of social, environmental and economical aspects of sustainability. Social sustainability in London City Hall appears on appropriateness and public good in the facility. London City Hall act as a symbol of redevelopment and civic community. Environmental sustainability of London City Hall summarized as using unique building form, double skin and underground water cooling system for the purpose of energy saving. Computer modeling technology was introduced to save construction cost for economic aspect of sustainability. Rational configuration of mechanical system strengthen the durability of facility. In case of London City Hall, the function of building, site condition and architectural concept fulfill the every aspects of sustainability in architecture. Besides these conditions, Foster applied sustainability to London City Hall as active and concrete design concept to complete its design goals.

The Chicken Thigh Adductor Profundus Free Muscle Flap: A Novel Validated Non-Living Microsurgery Simulation Training Model

  • Pafitanis, Georgios;Serrar, Yasmine;Raveendran, Maria;Ghanem, Ali;Myers, Simon
    • Archives of Plastic Surgery
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    • v.44 no.4
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    • pp.293-300
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    • 2017
  • Background Simulation training is becoming an increasingly important component of skills acquisition in surgical specialties, including Plastic Surgery. Non-living simulation models have an established place in Plastic Surgical microsurgery training, and support the principles of replacement, reduction and refinement of animal use. A more sophisticated version of the basic chicken thigh microsurgery model has been developed to include dissection of a type 1-muscle flap and is described and validated here. Methods A step-by-step dissection guide on how to perform the chicken thigh adductor profundus free muscle flap is demonstrated. Forty trainees performed the novel simulation muscle flap on the last day of a 5-day microsurgery course. Pre- and post-course microvascular anastomosis assessment, along with micro dissection and end product (anastomosis lapse index) assessment, demonstrated skills acquisition. Results The average time to dissect the flap by novice trainees was $82{\pm}24$ minutes, by core trainees $90{\pm}24$ minutes, and by higher trainees $64{\pm}21$ minutes (P=0.013). There was a statistically significant difference in the time to complete the anastomosis between the three levels of training (P=0.001) and there was a significant decrease in the time taken to perform the anastomosis following course completion (P<0.001). Anastomosis lapse index scores improved for all cohorts with post-test average anastomosis lapse index score of $3{\pm}1.4$ (P<0.001). Conclusions The novel chicken thigh adductor profundus free muscle flap model demonstrates face and construct validity for the introduction of the principles of free tissue transfer. The low cost, constant, and reproducible anatomy makes this simulation model a recommended addition to any microsurgical training curriculum.

The use of mobile computing devices in microsurgery

  • Pafitanis, Georgios;Hadjiandreou, Michalis;Miller, Robert;Mason, Katrina;Theodorakopoulou, Evgenia;Sadri, Amir;Taylor, Kirsten;Myers, Simon
    • Archives of Plastic Surgery
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    • v.46 no.2
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    • pp.102-107
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    • 2019
  • Mobile computing devices (MCDs), such as smartphones and tablets, are revolutionizing medical practice. These devices are almost universally available and offer a multitude of capabilities, including online features, streaming capabilities, high-quality cameras, and numerous applications. Within the surgical field, MCDs are increasingly being used for simulations. Microsurgery is an expanding field of surgery that presents unique challenges to both trainees and trainers. Simulation-based training and assessment in microsurgery currently play an integral role in the preparation of trainee surgeons in a safe and informative environment. MCDs address these challenges in a novel way by providing valuable adjuncts to microsurgical training, assessment, and clinical practice through low-cost, effective, and widely accessible solutions. Herein, we present a review of the capabilities, accessibility, and relevance of MCDs for technical skills acquisition, training, and clinical microsurgery practice, and consider the possibility of their wider use in the future of microsurgical training and education.

Nonlocality effects of MgB2 superconductor

  • Jeong Hun Yang;Jong Su You;Soo Kyung Lee;Kyu Jeong Song
    • Progress in Superconductivity and Cryogenics
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    • v.25 no.3
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    • pp.22-27
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    • 2023
  • Magnetic properties of MgB2 superconducting powder were investigated. M(H), the magnetic field H dependence of magnetization M, was measured and analyzed using a PPMS instrument. The MgB2 superconducting powder showed high critical current density Jc > ~ 107 A/cm2 and clean limit superconducting properties. The equilibrium magnetization Meq properties of MgB2 powders exhibiting various superconducting properties were studied. We find that the equilibrium magnetization Meq(H) properties of MgB2 powders showing conventional BCS properties deviate from the predictions of the standard local-London theory at temperatures below T = 19 K and are in good agreement with the generalized nonlocal-London theory. Nonlocal-London analysis was used to determine and analyze the nonlocal parameters. The temperature dependence of the London penetration depth values λ(T) was studied.

Self-starting vector phase conjugate laser oscillator in inverted Nd:YAG

  • Kim, D.H.;Udaiyan, D.;Green, R.P.M.;Crofts, G.J.;Damzen, M.J.
    • Journal of the Optical Society of Korea
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    • v.1 no.1
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    • pp.41-43
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    • 1997
  • We report the operation of a self-adaptive vector phase conjugate laser (VPCL) oscillator which compensates intracavity polarization distortion and wavefront aberration simultaneously. The VPCL in Nd:YAG gain media produce an output with energy of 125mJ in a 20ns single-longitudinal-mode pulse at 10Hz, which is unaffected by intracavity polarization distortion.