• Geomechanics and Engineering
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• v.34 no.6
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• pp.683-696
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• 2023

The destruction and fracture of rock masses are crucial components in engineering and there is an increasing demand for the study of the influence of rock mass heterogeneity on the safety of engineering projects. The numerical manifold method (NMM) has a unified solution format for continuous and discontinuous problems. In most NMM studies, material homogeneity has been assumed and despite this simplification, fracture mechanics remain complex and simulations are inefficient because of the complicated topology updating operations that are needed after crack propagation. These operations become computationally expensive especially in the cases of heterogeneous materials. In this study, a heterogeneous model algorithm based on stochastic theory was developed and introduced into the NMM. A new fracture algorithm was developed to simulate the rupture zone. The algorithm was validated for the examples of the four-point shear beam and semi-circular bend. Results show that the algorithm can efficiently simulate the rupture zone of heterogeneous rock masses. Heterogeneity has a powerful effect on the macroscopic failure characteristics and uniaxial compressive strength of rock masses. The peak strength of homogeneous material (with heterogeneity or standard deviation of 0) is 2.4 times that of heterogeneous material (with heterogeneity of 11.0). Moreover, the local distribution of parameter values can affect the configuration of rupture zones in rock masses. The local distribution also influences the peak value on the stress-strain curve and the residual strength. The post-peak stress-strain curve envelope from 60 random calculations can be used as an estimate of the strength of engineering rock masses.

• Journal of Oriental Neuropsychiatry
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• v.33 no.1
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• pp.49-78
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• 2022

Objectives: This study was conducted to evaluate the efficacy of Korean Medicine Therapy (KMT) for the treatment of Chemotherapy-induced Cognitive Impairment (CICI) through systematic review and meta-analysis of randomized controlled trials (RCTs) as proceeding research to further research the efficacy of KMT for CICI patients. Methods: We conducted a systematic review and meta-analysis according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines (PRISMA). The RCTs on the efficacy of KMT for treatment of CICI were searched by structured search strategies in MEDLINE, EMBASE, Cochrane library, CAJD, KISS, NDSL, KoreaMed, and OASIS. The searched RCTs were screened by inclusion and exclusion criteria. We evaluated the quality of the method in the included studies using the Jadad score and Cochran ROB tool. The efficacy outcomes were the Visual Analogue Scale (VAS) and the Clinical total Effective Rate (CER) of CICI. They were analyzed using mean difference for continuous variable or Relative Risk (RR) for Dichotomous variable in the random-effect model. The RevMan 5.3 program was used for meta-analysis. Results: We included 19 RCTs, including 653 participants, in the systematic review and meta-analysis. There were favorable results for the KMT group after the intervention compared with the pharmacotherapy group, physiotherapy group, and combined treatment group. KMT group showed improvement using CER and VAS compared with exercises, but their heterogeneities were slightly significant. KMT was more effective compared to the Rehabilitation program in CER and the subgroup analysis results showed that KMT had a significant difference compared to other therapies in VAS, to Medication therapy in CER. Conclusions: KMT presented reasonable evidence on improving the Clinical total Effective Rate and Visual Analogue Scale in CICI patients. However, further evaluation in future research is required.

• Computers and Concrete
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• v.32 no.1
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• pp.99-117
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• 2023

The crack under the influence of the higher intensities of the stresses grows and the structure gets collapsed with the time when the crack length reaches to critical value. Therefore, the fracture behavior of a structure in terms of stress intensity factors (SIF) becomes important to determine the remaining fracture strength and capacity of material and structure for avoiding catastrophic failure, increasing safety and further improvement in the design. The robustness of the method has been demonstrated by comparing the numerical results with analytical and experimental results of some problems. XFEM is used to model cracks and holes in structures and predict their strength and reliability under service conditions. Further, XFEM is extended with a stochastic method for predicting the sensitivity in terms of output COVs and fracture strength in terms of mean values of stress intensity factors (SIFs) of a structure with discontinuities (cracks and holes) under tensile loading condition with input individual and combined randomness in different system parameters. In stochastic technique, the second order perturbation technique (SOPT) has been used for the predicting the fracture behavior of the structures. The stochastic/perturbation technique is also known as Taylor series expansion method and it provides the reliable results if the input randomness is less than twenty percentage. From the present numerical analysis it is observed that, the crack tip near to the hole is under the influence of the stress concentration and the variational effect of the input random parameters on the crack tip in terms of the SIFs are lesser so the COVs are the less sensitive. The COVs of mixed mode SIFs are the most sensitive for the crack angles (α=45° to 90°) for all the values of c₁ and d₁. The plate with the shorter distance between hole and crack is the most sensitive with all the crack angles but the crack tip which is much nearer to the hole has the highest sensitivity.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.26 no.1
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• pp.31-39
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• 2022

In patients with neuroendocrine tumors with liver metastases (NETLMs), complete resection of both the primary and liver metastases is a potentially curative option. When complete resection is not possible, debulking of the tumour burden has been proposed to prolong survival. The objective of this systematic review was to evaluate the effect of curative surgery (R0-R1) and debulking surgery (R2) on overall survival (OS) in NETLMs. For the subgroup of R2 resections, outcomes were compared by the degree of hepatic debulking (≥ 90% or ≥ 70%). A systematic review of the literature was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines using PubMed, Medline, CINAHL, Cochrane, and Embase databases. Hazard ratios (HRs) were estimated for each study and pooled using a random-effects inverse-variance meta-analysis model. Of 538 articles retrieved, 11 studies (1,729 patients) reported comparisons between curative and debulking surgeries. After pooling these studies, OS was found to be significantly shorter in debulking resections, with an HR of 3.49 (95% confidence interval, 2.70-4.51; p < 0.001). Five studies (654 patients) compared outcomes between ≥ 90% and ≥ 70% hepatic debulking approaches. Whilst these studies reported a tendency for OS and progression-free survival to be shorter in those with a lower degree of debulking, they did not report sufficient data for this to be assessed in a formal meta-analysis. In patients with NETLM, OS following surgical resection is the best to achieve R0-R1 resection. There is also evidence for a progressive reduction in survival benefit with lesser debulking of tumour load.

• Clinical Endoscopy
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• v.57 no.5
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• pp.595-603
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• 2024

Background/Aims: Coaxial placement of double pigtail plastic stents (DPPS) through lumen-apposing metal stents (LAMSs) is commonly performed to reduce the risk of LAMS obstruction, bleeding, and stent migration when used for the drainage of pancreatic fluid collections (PFCs). A systematic review and meta-analysis were performed to compare the outcomes of LAMS alone and LAMS with coaxial DPPS placement in the management of PFCs. Methods: A systematic review was conducted to identify studies comparing LAMS and LAMS/DPPS for PFC drainage. Primary outcomes included the rate of clinical success, overall adverse events (AEs), bleeding, infection, occlusion, and stent migration. The pooled effect size was summarized using a random-effects model and compared between LAMS and LAMS/DPPS by calculating odds ratios (ORs). Results: Nine studies involving 709 patients were identified (338 on LAMS and 371 on LAMS/DPPS). LAMS/DPPS was associated with a reduced risk of stent obstruction (OR, 0.59; p=0.004) and infection (OR, 0.55; p=0.001). No significant differences were observed in clinical success (OR, 0.96; p=0.440), overall AEs (OR, 0.57; p=0.060), bleeding (OR, 0.61; p=0.120), or stent migration (OR, 1.03; p=0.480). Conclusions: Coaxial DPPS for LAMS drainage of PFCs is associated with a reduced risk of stent occlusion and infection; however, no difference was observed in the overall AE rates or bleeding.

• Geophysics and Geophysical Exploration
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• v.11 no.2
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• pp.137-147
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• 2008

Fault rupture directivity of the Odaesan earthquake, which was inferred to be the main cause of the high PGAvalue (> 0.1 g) unusually observed at the near-source region, was analyzed by using the data from the nearby (R < 100 km) dense seismic stations. The Boatwright's method (2007) was adopted for this purpose in which the azimuth and takeoff angle of the unilateral rupture directivity function could be estimated based on the relative peak ground-motions of seismic stations resulting from the nature of the rupture directivity. In this study, the approximate values of the relative peak ground-motions was derived from the difference between the log residuals of the point-source spectral model (Boore, 2003) for the main and secondary events based on the Random Vibration Theory. In this derivation, the spectral difference for a frequency range between the source corner frequencies of main and secondary events was considered to reflect only the effect of the fault directivity. The inversion result of the model parameters for the fault directivity function showed that the fault-plane of NWW-SEE direction dipping steeply to the North with high rupture velocity near upward in SE direction is responsible for the observed high level of ground-motion at the near-source region.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.95-106
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• 2017

The purpose of this study was to identify the effects of non-pharmacological interventions for Korean adults with insomnia. Literature review was performed for articles published between 2000 and 2016 in electronic databases. Sixteen articles met the inclusion criteria. Data were analyzed by R version 3.3.1 for windows. Meta-analysis was performed using the random effects model; the overall effect size of non-pharmacological interventions on sleep was significantly large (Hedges' g=2.36, 95% CI: 1.44~3.28). For heterogeneity, a moderator analysis was performed using the study design, participants, age group, intervention, presence of hospitalization, and sleep measurement. There was a statistically significant difference between the effects of moderator variables, except for the study design and participants. Of the interventions, auricular acupressure reported to have the largest effect size on sleep. The findings in this study indicate that non-pharmacological interventions have a positive effect on sleep, providing objective evidence to improve sleep in adults with insomnia using effective interventions.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6077-6081
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• 2012

Background: This study was performed to analyze the prognostic implications of pretreatment or preoperative thrombocytosis in women with gynecologic malignancies. Material and Methods: We surveyed 2 medical databases, PubMed and EMBASE, to identified all relevant studies. A total of 14 (n=3,490) that evaluated the link between thrombocytosis and 5-year survival were included. REVMAN version 5.1 was used for our analysis and publication bias was evaluated using the Begg's funnel plot and tested by STATA 11.0. Risk ratios (RRs) with 95% confidence intervals (CIs) generated by the random effect model were used to assess the strength of any association. Results: 709(20.3%) of the 3,490 patients exhibited thrombocytosis (platelet counts > $400{\times}10^9/L$) at primary diagnosis, and their mortality was 1.62-fold higher compared with the others (RR=1.62, 95%CI=[1.28-2.05], p<0.0001). Thrombocytosis failed to have a stronger effect on the survival of advanced patients of stages III to IV in our study (n=478, RR=1.29, 95% CI=[1.13-1.48], p=0.0003), nor in women with cervical cancer in stage IB (n=1371, RR=1.73, 95% CI=[1.71-2.58], p=0.007). In addition, when adjusted for different carcinoma, it was associated with worse prognosis for all except the ones with vulvar cancer (n=201, RR=0.43, 95% CI=[0.14-1.29], p=0.13). Conclusions: This meta-analysis indicated that thrombocytosis might be associated with a worse prognosis for patients with gynecologic malignancies but without specificity or sensitivity for the ones in advanced stage. When adjusted for different gynecologic malignancies, it showed a significant effect on survival of all except vulvar cancers.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.323-335
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• 2016

Breast cancer risk assessment has developed during years and evaluation of genetic factor affecting risk of breast cancer is an important component of this risk assessment. The aim of this meta-analysis was to investigate the role of XRCC1 polymorphisms (Arg194Trp, Arg280His and Arg399Gln) in risk of breast cancer among different population and categories of menopausal status.PubMed, Medline, Web of Science, and PubMed Central were systematically searched to identify studies evaluating association between breast cancer and XRCC1 gene polymorphisms (Arg194Trp, Arg280His and Arg399Gln). Two authors independently extracted required information. Odds Ratios were pooled for four genetic inheritance models using both fixed and the DerSimonian and Laird random-effect models. Egger's test and contour-enhanced funnel plot was used to evaluate publication bias and small study effect. Additional subgroup analysis was performed for menopausal status, ethnicity, and source of controls. After evaluation and applying inclusion criteria on extracted studies, fifty three studies were included in this meta-analysis. For polymorphisms of Arg194Trp and Arg280His, no significant association was observed in all genetic models. Arg194Trp had a protective effect in post-menopausal status only in homozygote model (OR=0.57 [0.37-0.88]). Arg399Gln showed significant association with breast cancer in homozygote (OR=1.21 [1.10-1.34]), dominant (OR=1.09 [1.03-1.15]) and recessive (OR=1.21 [1.09- 1.35]) genetic models. Arg399Gln was associated with higher risk in post-menopausal status for homozygote and heterozygote models. Our findings suggest that XRCC1 gene polymorphisms modify breast cancer risk in different populations and different categories of menopausal status.

• Therapeutic Science for Rehabilitation
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• v.9 no.4
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• pp.107-120
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• 2020

Objective : The purpose of this study was to investigate the effectiveness and basis of rehabilitation intervention in patients with spinal cord injury by systematic review and meta-analysis of randomized controlled studies. Methods : Two researchers independently searched and selected a study published in an academic journal using a search term in an international thesis database. A total of 21 studies met the selection criteria, and qualitative evaluation of the study was conducted using the PEDro Scale. Meta-analysis was performed using Comprehensive Meta-Analysis 3.0 program. Results : A total of 713 subjects were included. The results of the meta-analysis showed a score of 0.406 (95.0% confidence interval: 0.221 ~ 0.591) for intervention using physical activity and 0.505 (95.0% confidence interval: 0.449 ~ 1.528) for electronic stimulation therapy, which showed medium effect; educational intervention had a 0.248 (95.0% confidence interval: 0.033 ~ 0.464), and mixed intervention 0.280 (95.0% confidence interval: 0.122 ~ 0.438). It was shown that the effect of small (small). There was a significant heterogeneity in the statistical heterogeneity test, and thus the random effects model was selected and analyzed. Conclusion : The results showed that rehabilitation interventions were effective for patients with spinal cord injury. During the rehabilitation of spinal cord injury patients, clinicians are expected to contribute to the development of programs to improve their lifestyles.