Normal Values of High-resolution Manometry Parameters With Provocative Maneuvers

( Hui Su ),( Amanda J Krause ),( Melina Masihi ),( Jacqueline Prescott ),( Alex Decorrevont ),( Emma Germond ),( Dave Karasik ),( Wenjun Kou ),( John E Pandolfino ),( Dustin A Carlson ) 대한소화기기능성질환·운동학회(구 대한소화관운동학회) 2021 Journal of Neurogastroenterology and Motility (JNM Vol.27 No.3

Background/Aims Incorporation of complementary and provocative test swallows to the high-resolution manometry (HRM) protocol offers potential to address limitations posed by HRM protocols that involve only a single swallow type. The aim of this study is to describe normal findings of a comprehensive HRM testing protocol performed on healthy asymptomatic volunteers. Methods Thirty healthy asymptomatic volunteers completed HRM with 5-mL liquid swallows in the supine position. They also completed 5-mL liquid swallows in the upright position, viscous swallows, solid test swallows, multiple rapid swallows, and a rapid drink challenge. HRM studies were analyzed via Chicago classification version 3.0. Results The median (5th-95th percentiles) for integrated relaxation pressure (IRP) on supine swallows was 11 (4-16) mmHg; IRP was lower than supine on upright liquid 9 (0-17) mmHg, viscous 6 (0-15) mmHg, solid 9 (1-19) mmHg, multiple rapid swallows 3 (0-12) mmHg, and rapid drink challenge 5 (-3-12) mmHg; P < 0.005. While an “elevated” IRP value was observed on 1 to 2 test maneuvers in 8/30 (27%) subjects, all 30 subjects had an IRP value < 12 mmHg on at least one of the test maneuvers. Conclusions Normal values and findings from a comprehensive HRM testing protocol are reported based on evaluation of 30 healthy asymptomatic volunteers. Isolated “abnormalities” of IRP and contractile parameters were observed in the majority (80%) of these asymptomatic subjects, while all subjects also had normal features observed. Thus, the definition of “normal” should be recalibrated to focus on the entirety of the study and not individual metrics. (J Neurogastroenterol Motil 2021;27:354-362)

Performing High-resolution Impedance Manometry After Endoscopy With Conscious Sedation Has Negligible Effects on Esophageal Motility Results

( Hui Su ),( Dustin A Carlson ),( Erica Donnan ),( Wenjun Kou ),( Jacqueline Prescott ),( Alex Decorrevont ),( Francesca Shilati ),( Melina Masihi ),( John E Pandolfino ) 대한소화기기능성질환·운동학회(구 대한소화관운동학회) 2020 Journal of Neurogastroenterology and Motility (JNM Vol.26 No.3

Background/Aims High-resolution manometry (HRM) performed without sedation is the standard procedure. However, some patients cannot tolerate transnasal placement of the manometry catheter. We aim to assess the practice of performing manometry after endoscopy with conscious sedation by evaluating its impact on esophageal motility findings. Methods Twelve asymptomatic adult volunteers and 7 adult patients completed high-resolution impedance manometry (HRIM) approximately 1 hour after conscious sedation with midazolam and fentanyl (post-sedation) and again on a different day with no-sedation. The no-sedation HRIM involved 2 series of swallows separated in time by 20 minutes (no-sedation-1 and no-sedation-2) for the volunteers; patients completed only 1 series of swallows for no-sedation HRM. Results A motility diagnosis of normal motility was observed in all 12 volunteers post-sedation. Two volunteers had a diagnosis of borderline ineffective esophageal motility, one during the no-sedation-1 period and the other during the no-sedation-2 period; all of the other no-sedation HRIM studies yielded a normal motility diagnosis. Six of seven patients had the same diagnosis in both no-sedation and post-sedation HRM, including 1 distal esophageal spasm, 3 achalasia (2 type II and 1 type III), and 2 esophagogastric junction outflow obstruction. Only one patient’s HRM classification changed from ineffective esophageal motility at no-sedation to normal esophageal motility at post-sedation. Conclusions Performing HRIM after endoscopy with conscious sedation had minimal clinical impact on the motility diagnosis or motility parameters. Thus, this approach may be a viable alternative for patients who cannot tolerate unsedated catheter placement. (J Neurogastroenterol Motil 2020;26:352-361)

Chinese-Americans’ Confusion and Pursuit of Their Ethical Identity in Steer Toward Rock

Hui Su,Lingqin Yi 건국대학교 아시아·디아스포라 연구소 2015 International Journal of Diaspora&Cultural Critici Vol.5 No.2

Steer Toward Rock, a novel written by the female Chinese- American writer Fae Myenne Ng, presents the process of Jack’s confusion and pursuit of his own ethical identity during The Chinese Confession Program period. Because of the special historical period and his personal experience, Jack, as a Chinese immigrant, is in displacement and confusion of his family ethical identity as well as in absence of biological and social ethical identity, which puts him in an ethical predicament. The displacement and absence of Jack’s ethical identity coupled with his hard pursuit are closely related to the special ethical environment of Chinese-American immigrants in the middle of 20th century, which show the traumas and disasters caused by American racial immigration policies — the Chinese Exclusion ACT, and uncover the early Chinese-American immigrants’ history of silence.

Comparative Research on Parameter Estimation via Particle Filtering

Huisu Jang(장희수),Youngdoo Son(손영두),Jaewook Lee(이재욱),Gyusik Han(한규식) 한국경영과학회 2014 한국경영과학회 학술대회논문집 Vol.2014 No.5

Theoretical prediction on thickness distribution of cement paste among neighboring aggregates in concrete

Huisu Chen,Lambertus Johannes Sluys,Piet Stroeven,Wei Sun 사단법인 한국계산역학회 2011 Computers and Concrete, An International Journal Vol.8 No.2

By virtue of chord-length density function from the field of statistical physics, this paper introduced a quantitative approach to estimate the distribution of cement paste thickness between aggregates in concrete. Dynamics mixing method based on molecular dynamics was employed to generate one model structure, then image analysis algorithm was used to obtain the distribution of thickness of cement paste in model structure for the purpose of verification. By comparison of probability density curves and cumulative probability curves of the cement paste thickness among neighboring aggregates, it is found that the theoretical results are consistent with the simulation. Furthermore, for the model mortar and concrete mixtures with practical volume fraction of Fuller-type aggregate, this analytical formula was employed to predict the influence of aggregate volume fraction and aggregate fineness. And evolution of its mean values were also investigated with the variation of volume fraction of aggregate as well as the fineness of aggregates in model mortars and concretes.

Comparative Research on Parameter Estimation via Particle Filtering

Huisu Jang(장희수),Youngdoo Son(손영두),Jaewook Lee(이재욱),Gyusik Han(한규식) 대한산업공학회 2014 대한산업공학회 춘계학술대회논문집 Vol.2014 No.5

Motion Adaptive Patch-Based Low-Rank Approach for Compressed Sensing Cardiac Cine MRI

Huisu Yoon,Kyung Sang Kim,Kim, Daniel,Bresler, Yoram,Jong Chul Ye IEEE 2014 IEEE transactions on medical imaging Vol.33 No.11

<P>One of the technical challenges in cine magnetic resonance imaging (MRI) is to reduce the acquisition time to enable the high spatio-temporal resolution imaging of a cardiac volume within a short scan time. Recently, compressed sensing approaches have been investigated extensively for highly accelerated cine MRI by exploiting transform domain sparsity using linear transforms such as wavelets, and Fourier. However, in cardiac cine imaging, the cardiac volume changes significantly between frames, and there often exist abrupt pixel value changes along time. In order to effectively sparsify such temporal variations, it is necessary to exploit temporal redundancy along motion trajectories. This paper introduces a novel patch-based reconstruction method to exploit geometric similarities in the spatio-temporal domain. In particular, we use a low rank constraint for similar patches along motion, based on the observation that rank structures are relatively less sensitive to global intensity changes, but make it easier to capture moving edges. A Nash equilibrium formulation with relaxation is employed to guarantee convergence. Experimental results show that the proposed algorithm clearly reconstructs important anatomical structures in cardiac cine image and provides improved image quality compared to existing state-of-the-art methods such as k-t FOCUSS, k-t SLR, and MASTeR.</P>

Spatial dispersion of aggregate in concrete a computer simulation study

Huisu Chen,Piet Stroeven,Jing Hu 한국계산역학회 2006 Computers and Concrete, An International Journal Vol.3 No.5

Experimental research revealed that the spatial dispersion of aggregate grains exerts pronounced influences on the mechanical and durability properties of concrete. Therefore, insight into this phenomenon is of paramount importance. Experimental approaches do not provide direct access to three-dimensional spacing information in concrete, however. Contrarily, simulation approaches are mostly deficient in generating packing systems of aggregate grains with sufficient density. This paper therefore employs a dynamic simulation system (with the acronym SPACE), allowing the generation of dense random packing of grains, representative for concrete aggregates. This paper studies by means of SPACE packing structures of aggregates with a Fuller type of size distribution, generally accepted as a suitable approximation for actual aggregate systems. Mean free spacing , mean nearest neighbour distance (NND) between grain centres , and the probability density function of D3 are used to characterize the spatial dispersion of aggregate grains in model concretes. Influences on these spacing parameters are studied of volume fraction and the size range of aggregate grains. The values of these descriptors are estimated by means of stereological tools, whereupon the calculation results are compared with measurements. The simulation results indicate that the size range of aggregate grains has a more pronounced influence on the spacing parameters than exerted by the volume fraction of aggregate. At relatively high volume density of aggregates, as met in the present cases, theoretical and experimental values are found quite similar. The mean free spacing is known to be independent of the actual dispersion characteristics (Underwood 1968); it is a structural parameter governed by material composition. Moreover, scatter of the mean free spacing among the serial sections of the model concrete in the simulation study is relatively small, demonstrating the sample size to be representative for composition homogeneity of aggregate grains. The distribution of observed in this study is markedly skew, indicating a concentration of relatively small values of . The estimate of the size of the representative volume element (RVE) for configuration homogeneity based on NND exceeds by one order of magnitude the estimate for structure-insensitive properties. This is in accordance with predictions of Brown (1965) for composition and configuration homogeneity (corresponding to structure-insensitive and structure-sensitive properties) of conglomerates.

A cutting force prediction framework based on machine learning methods according to various cutting conditions in milling process

Huisu Kim,Jeongin Koo 한국생산제조학회 2020 한국생산제조시스템학회 학술발표대회 논문집 Vol.2020 No.10

Effectiveness of workers’ general health examination in Korea by health examination period and compliance

Huisu Eom,Jun-Pyo Myong,Eun-A Kim,Bohwa Choi,Soon Woo Park,Young Joong Kang 대한직업환경의학회 2017 대한직업환경의학회지 Vol.29 No.-

Background: Our study evaluated the effectiveness of the Workers’ General Health Examination by health examination period and compliance. Methods: A retrospective cohort of the health examination participants in 2006 (baseline year: N = 6,527,045) was used. We identified newly occurring cardio-cerebrovascular disease over 7 years (from 2007 to 2013). After stratification by age, sex, and national health insurance type, we identified 7 years’ cumulative incidence of cardio-cerebrovascular disease by health examination compliance and estimated its relative risk by health examination period and compliance. Results: The compliant group presented a lower cumulative incidence of cardio-cerebrovascular disease than the noncompliant group; this result was consistent across sex, working age (40s and 50s), and workplace policyholder. Relative risk of cardio-cerebrovascular disease by health examination period (1 and 2 years) showed statistically significant results in ischemic heart disease for male participants. Of men in their 40s, office workers (over a 2-year period) presented statistically higher relative risk of ischemic heart disease than non-office workers (over a 1-year period: 1.03; 95% confidence interval, 1.02–1.03). However, there were no consistent results in ischemic cerebrovascular disease and hemorrhagic cerebrovascular disease for men or cardio-cerebrovascular disease for women. Conclusion: A 1-year period of Workers’ General Health Examinations in non-office workers had a more significant prevention effect on ischemic heart disease than a 2-year period in office workers among working age (40s–50s) men. It is, however, necessary to consider that prevention of cardio-cerebrovascular disease can be partially explained by their occupational characteristics rather than by health examination period.