The quality of cement-treated soil columns is normally assured based on the unconfined compressive strength q
u
of core samples. q
u
of core samples varies spatially and the statistical parameters of ...q
u
(i.e., mean µ
q
u
, variance
, and autocorrelation distance θ
q
u
) are adopted in quality assurance procedures. The statistical parameters of q
u
evaluated from the core sample strengths have a statistical uncertainty depending on the statistical sample size. The present study investigates the influence of the statistical sample size on the evaluation of overall strength of a cement-treated soil column. A probabilistic framework in which a Bayesian inference analysis and a finite element method analysis are incorporated is used to calculate the overall strength while simultaneously considering the statistical uncertainty and spatial variability of core strength. The probabilistic framework is briefly described, and a parametric analysis is performed to investigate the influence of the statistical sample size on the evaluation of the overall strength of a full-scale column. The numerical results show that the sample size and spatial correlation influence the variability of the overall strength, and the influence can be reasonably described using an equivalent number of independent data.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A finite‐element method (FEM) analysis incorporating with random field theory is a powerful tool to predict the behavior of ground improvement by deep cement mixing with spatial variability. In the ...analysis, statistical parameters of the strength (i.e., mean, variance, and autocorrelation distance) are normally held constant. However, these parameters involve a statistical uncertainty when evaluated from strengths of core samples retrieved from the cement‐treated soil columns. This study presents a probabilistic analysis framework to evaluate the overall strength of a cement‐treated soil column considering the statistical uncertainty and spatial variability of the core strength. A Bayesian inference analysis and an FEM analysis incorporating with the random field theory are combined in a Monte Carlo framework to simultaneously consider the statistical uncertainty and spatial variability. The statistical uncertainty of the core strength is evaluated by the Bayesian inference approach, where the probability distribution of the statistical parameters is inferred from the observation data. The inferred statistical parameters of the strength are used for generating random field realizations, and the FEM analysis is conducted on the generated realizations. An example analysis is conducted to illustrate the details of the approach. The results of the example simulation demonstrate that the proposed framework can provide the probabilistic characteristic of the overall strength of the cement‐treated column when the statistical uncertainty and the spatial variability of the core strength need to be simultaneously considered.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The statistical parameters for the strength of cement-treated soil are evaluated by the strength of cored samples retrieved from cement-treated columns for a quality assurance procedure in the deep ...mixing method. The sample parameters include the statistical uncertainty associated with the statistical sample size and other factors. Therefore, a probabilistic characterization of the statistical parameters of strength is required to quantify the statistical uncertainty in the quality assurance process. This paper presents a quantitative analysis of the statistical uncertainty for the estimation of the strength of cement-treated columns. The Bayesian approach is adopted to evaluate the statistical uncertainty occurring in the determination of the statistical parameters of the strength from observed data. The inference is performed via a Markov chain Monte Carlo method, in which samples of the parameters are sequentially drawn from a joint posterior probability distribution. An example analysis is performed to illustrate the statistical uncertainty of the unconfined compressive strength of cored samples retrieved from cement-treated columns. The results show that the statistical parameters, inferred from the data with the sample size of approximately 40, include considerable uncertainty. The variability of the estimated statistical parameters is found to depend on both the sample size and the spatial correlation. The influence of the statistical uncertainty, caused in the estimation of the mean and standard deviations in strength, is examined within the framework of quality assurance in the deep mixing method.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
AbstractThe quality of cement-treated soil columns is usually assessed by examining the strength of cored samples. This paper presents a finite-element analysis approach with random field theory for ...assessing the quality of a cement-treated soil column from which cored samples are retrieved. Monte Carlo simulations with conditional distribution (conditional simulation) were conducted to generate spatial dependence random fields with the data known at some locations. Simulations without the known data (unconditional simulation) were also performed for comparison. Using the random field samples generated from the Monte Carlo simulations, finite-element analysis was performed to simulate the compression behavior of a full-scale column in which material properties vary with a presence of spatial autocorrelation. Finite-element analysis with conditional simulation predicts the overall strength of a targeted cement-treated soil column appropriately, and the overall strength variability obtained with the conditional simulation is lower than that obtained with the unconditional simulation. The results suggest that the conditional simulation offers advantages over the unconditional simulation when assessing the probability of failure of a cement-treated soil column with large autocorrelation distance.
The metastasis of tumors to the stomach is rare, which underlies the clinical problems regarding their diagnosis and treatment. The present review summarizes the current knowledge regarding the ...clinicopathological characteristics, therapeutic strategies and outcomes for metastatic tumors in the stomach. The primary malignancies of the metastatic tumors in the stomach were most often breast cancers (27.9 %), followed by lung cancer (23.8 %), esophageal cancer (19.1 %), renal cell carcinoma (RCC; 7.6 %) and malignant melanoma (7.0 %). In cases of breast cancer and RCC as the primary malignancy, the median interval between the treatment of the primary tumor and diagnosis of the metastatic tumor in the stomach (IPM) was 50–78 and 75.6 months, respectively, highlighting the fact that the metastatic spread to the stomach may occur many years after the initial treatment of the cancer. In nine patients with metastatic gastric tumors arising from ovarian cancer, an endoscopic examination revealed submucosal tumors in six patients (66.7 %), with a median IPM of 30 months. Appropriate systemic treatment for these tumors is the preferred therapeutic strategy. Although solitary metachronous gastric metastasis several years after treatment of the primary tumor is an exceptionally rare event, surgical resection of metastatic gastric tumors may be recommended to control hemorrhaging or for selected tumors.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Near-infrared (NIR) fluorescence imaging has better tissue penetration, allowing for the effective rejection of excitation light and detection deep inside organs. Indocyanine green (ICG) generates ...NIR fluorescence after illumination by an NIR ray, enabling real-time intraoperative visualization of superficial lymphatic channels and vessels transcutaneously. The HyperEye Medical System (HEMS) can simultaneously detect NIR rays under room light to provide color imaging, which enables visualization under bright light. Thus, NIR fluorescence imaging using ICG can provide for excellent diagnostic accuracy in detecting sentinel lymph nodes in cancer and microvascular circulation in various ischemic diseases, to assist us with intraoperative decision making. Including HEMS in this system could further improve the sentinel lymph node mapping and intraoperative identification of blood supply in reconstructive organs and ischemic diseases, making it more attractive than conventional imaging. Moreover, the development of new laparoscopic imaging systems equipped with NIR will allow fluorescence-guided surgery in a minimally invasive setting. Future directions, including the conjugation of NIR fluorophores to target specific cancer markers might be realistic technology with diagnostic and therapeutic benefits.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
AbstractThe strength of soil treated by cement deep mixing varies greatly, even at a single column, because of the variability of in situ soil properties, the variability of mixing effectiveness, and ...other factors. The variation in strength would affect the entire behavior of the cement-treated column. This paper presents a numerical experiment that investigates the effect of spatial correlation on the unconfined compressive strength of cement-treated columns. Finite element analyses incorporating random-field theory were performed to simulate the unconfined compression behavior of full-scale column samples in which the material properties vary with respect to spatial autocorrelation. The numerical results indicate that spatial autocorrelation affects the compression behavior of full-scale cement-treated columns. The overall strength of the sample in the absence of spatial autocorrelation is slightly lower than that of the uniform sample of mean strength. On the other hand, the overall strength of the sample in the presence of spatial autocorrelation is significantly lower than that of the uniform sample of mean strength. These results suggest that spatial autocorrelation should be considered when evaluating the overall strength of full-scale cement-treated columns within a relevant design procedure.
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DOBA, FGGLJ, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Purpose
To investigate the usefulness of clinicopathological systemic inflammatory response and nutritional biomarkers for predicting the efficacy of nivolumab in patients with advanced gastric ...cancer.
Methods
The subjects of this study were 29 patients who received nivolumab treatment for advanced gastric cancer at the Kochi Medical School between 2017 and 2019. Clinicopathological information, including systemic inflammatory response data, were obtained to investigate the associations between baseline cancer-related prognostic variables and survival outcomes.
Results
Immune-related adverse events (irAEs) of any grade were identified in 34.5% (10/29) of the patients. The median progression-free survival of patients with irAEs was significantly greater than that of patients without irAEs (5.8 months vs. 1.2 months, respectively;
P
= 0.028). The neutrophil to lymphocyte ratio (NLR) after 4 weeks of treatment in the complete response (CR) or partial response (PR) group was significantly lower than that in the stable disease (SD) or progression disease (PD) group (2.2 vs. 2.9, respectively;
P
= 0.044). The prognostic nutrition index (PNI) before treatment in the CR or PR group was significantly higher than that in the SD or PD group (37.1 vs. 32.1, respectively;
P
= 0.011). The PNI 8 weeks after treatment and the Glasgow prognostic score (GPS) before treatment were significantly associated with a poor outcome.
Conclusion
The irAE, NLR, PNI, and GPS may be useful predictive markers for nivolumab efficacy in patients with advanced gastric cancer.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
5-aminolevulinic acid (ALA) is a naturally occurring amino acid that is a protoporphyrin IX (PpIX) precursor and a next-generation photosensitive substance. After exogenous administration of ALA, ...PpIX specifically accumulates in cancer cells owing to the impaired metabolism of ALA to PpIX in mitochondria, which results in a red fluorescence following irradiation with blue light and the formation of singlet oxygen. Fluorescence navigation by photodynamic diagnosis (PDD) using ALA provides good visualization and detection of gastric cancer lesions and is a potentially valuable diagnostic tool for gastric cancer for evaluating both the surgical resection margins and extension of the lesion. Furthermore, PDD using ALA might be used to detect peritoneal metastases during preoperative staging laparoscopy, where it could provide useful information for the selection of a therapeutic approach. Another promising application for this modality is in the evaluation of lymph node metastases. Photodynamic therapy (PDT) using ALA to cause selective damage based on the accumulation of a photosensitizer in malignant tissue is expected to be a non-invasive endoscopic treatment for superficial early gastric cancer. ALA has the potential to be used not only as a diagnostic agent but also as a therapeutic drug, resulting in a new strategy for cancer diagnosis and therapy. Here, we review the current use of PDD and PDT in gastric cancer and evaluate its future potential beyond conventional modalities combined with a light energy upconverter, a light-emitting diode and near-infrared rays as light sources.
Background
Postoperative anastomotic leakage is a severe complication after gastric tube reconstruction during esophagectomy. The aim of this study was to evaluate the usefulness of postoperative ...endoscopic assessment of anastomosis and its correlation with intraoperative indocyanine green (ICG) fluorescence assessment of the gastric tube.
Methods
We retrospectively reviewed 72 consecutive patients who underwent gastric tube reconstruction using the ICG fluorescence method during esophagectomy. Forty-six patients underwent the ICG line-marking method (LMM group; ICG before gastric tube creation). The other 26 underwent the conventional procedure and comprised the control group (ICG after gastric tube creation). Postoperative endoscopic assessment (PEA) of anastomosis was performed 7 days after surgery and results were classified as follows: grade 1 (normal or partial white coat), grade 2 (ulcer comprising less than half the circumference), and grade 3 (ulcer comprising more than half the circumference).
Results
Anastomotic leakage occurred in 7 of 72 patients (9.7%). The incidence of anastomotic leakage in the LMM group was tended to be lower than those in the control group (6.5% vs. 15.4%;
P
= 0.244). Of the 40 patients who underwent PEA, 3 (7.5%) had leakage. PEA grading was significantly associated with anastomotic leakage (
P
< 0.001). Better intraoperative ICG assessment was significantly associated with better endoscopic assessment grade (
P
= 0.041).
Conclusion
Intraoperative ICG assessment of the gastric tube was associated with PEA grading on anastomosis during esophagectomy.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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