Summary
The hybrid finite‐discrete element method (FDEM) is widely used for engineering applications, which, however, is computationally expensive and needs further development, especially when rock ...fracture process is modeled. This study aims to further develop a sequential hybrid FDEM code formerly proposed by the authors and parallelize it using compute unified device architecture (CUDA) C/C++ on the basis of a general‐purpose graphics processing unit (GPGPU) for rock engineering applications. Because the contact detection algorithm in the sequential code is not suitable for GPGPU parallelization, a different contact detection algorithm is implemented in the GPGPU‐parallelized hybrid FDEM. Moreover, a number of new features are implemented in the hybrid FDEM code, including the local damping technique for efficient geostatic stress analysis, contact damping, contact friction, and the absorbing boundary. Then, a number of simulations with both quasi‐static and dynamic loading conditions are conducted using the GPGPU‐parallelized hybrid FDEM, and the obtained results are compared both quantitatively and qualitatively with those from either theoretical analysis or the literature to calibrate the implementations. Finally, the speed‐up performance of the hybrid FDEM is discussed in terms of its performance on various GPGPU accelerators and a comparison with the sequential code, which reveals that the GPGPU‐parallelized hybrid FDEM can run more than 128 times faster than the sequential code if it is run on appropriate GPGPU accelerators, such as the Quadro GP100. It is concluded that the GPGPU‐parallelized hybrid FDEM developed in this study is a valuable and powerful numerical tool for rock engineering applications.
Abstract
Osteoarthritis (OA), primarily characterized by articular cartilage destruction, is the most common form of age-related degenerative whole-joint disease. No disease-modifying treatments for ...OA are currently available. Although OA is primarily characterized by cartilage destruction, our understanding of the processes controlling OA progression is poor. Here, we report the association of OA with increased levels of osteoclast-associated receptor (OSCAR), an immunoglobulin-like collagen-recognition receptor. In mice, OSCAR deletion abrogates OA manifestations, such as articular cartilage destruction, subchondral bone sclerosis, and hyaline cartilage loss. These effects are a result of decreased chondrocyte apoptosis, which is caused by the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in induced OA. Treatments with human OSCAR-Fc fusion protein attenuates OA pathogenesis caused by experimental OA. Thus, this work highlights the function of OSCAR as a catabolic regulator of OA pathogenesis, indicating that OSCAR blockade is a potential therapy for OA.
The aim of this study was to evaluate whether stage at cancer diagnosis differed according to patient economic status.
A total of 10,528 patients with cancer of the stomach, colorectum, breast, or ...cervix, which are target organs of the Korean National Cancer Screening Program (NCSP; fully implemented in 2005) were extracted from population-based cancer registries. The patients were classified into four groups based on socioeconomic status (SES), as determined using their National Health Insurance (NHI) monthly premium at the time of cancer diagnosis. Cancer stage at diagnosis was defined as early (in situ/local) or late stage (regional/distant) based on the Surveillance, Epidemiology, and End Results (SEER) summary stage. Multivariable logistic regression analysis was performed to estimate the risk of non-local stage using age, residential area, and community deprivation index as covariates.
The lowest SES subjects showed significantly higher risks of being diagnosed at a later stage for stomach, colorectal, and female breast cancer, but not for cervical cancer, compared with the highest SES subjects. The estimated ORs were 1.28 (95% CI, 1.10–1.49), 1.29 (95% CI, 1.03–1.61), and 1.35 (95% CI, 1.02–1.81) in the lowest SES subjects with stomach, colorectal, and breast cancer, respectively.
In conclusion, later stage diagnoses of stomach, colon, and female breast cancer are still associated with SES in Korea in the era of the NCSP for the lower SES population.
•Advanced stage was more frequent in cancer patients with lower economic status.•Differences of stage by SES were found in stomach, colorectal, and breast cancer.•Disparities still exist after the National Cancer Screening program in Korea.
In livestock industry, there is growing interest in methods to increase the production efficiency of livestock to address food shortages, given the increasing global population. With the advancements ...in gene engineering technology, it is a valuable tool and has been intensively utilized in research specifically focused on human disease. In historically, this technology has been used with livestock to create human disease models or to produce recombinant proteins from their byproducts. However, in recent years, utilizing gene editing technology, cattle with identified genes related to productivity can be edited, thereby enhancing productivity in response to climate change or specific disease instead of producing recombinant proteins. Furthermore, with the advancement in the efficiency of gene editing, it has become possible to edit multiple genes simultaneously. This cattle breed improvement has been achieved by discovering the genes through the comprehensive analysis of the entire genome of cattle. The cattle industry has been able to address gene bottlenecks that were previously impossible through conventional breeding systems. This review concludes that gene editing is necessary to expand the cattle industry, improving productivity in the future. Additionally, the enhancement of cattle through gene editing is expected to contribute to addressing environmental challenges associated with the cattle industry. Further research and development in gene editing, coupled with genomic analysis technologies, will significantly contribute to solving issues that conventional breeding systems have not been able to address.
This systematic review and meta-analysis aimed to summarize the effects of forest therapy on depression and anxiety using data obtained from randomized controlled trials (RCTs) and quasi-experimental ...studies. We searched SCOPUS, PubMed, MEDLINE(EBSCO), Web of science, Embase, Korean Studies Information Service System, Research Information Sharing Service, and DBpia to identify relevant studies published from January 1990 to December 2020 and identified 20 relevant studies for the synthesis. The methodological quality of eligible primary studies was assessed by ROB 2.0 and ROBINS-I. Most primary studies were conducted in the Republic of Korea except for one study in Poland. Overall, forest therapy significantly improved depression (Hedges's g = 1.133; 95% confidence interval (CI): -1.491 to -0.775) and anxiety (Hedges's g = 1.715; 95% CI: -2.519 to -0.912). The quality assessment resulted in five RCTs that raised potential concerns in three and high risk in two. Fifteen quasi-experimental studies raised high for nine quasi-experimental studies and moderate for six studies. In conclusion, forest therapy is preventive management and non-pharmacologic treatment to improve depression and anxiety. However, the included studies lacked methodological rigor and required more comprehensive geographic application. Future research needs to determine optimal forest characteristics and systematic activities that can maximize the improvement of depression and anxiety.
Surface glazing and low-temperature degradation (LTD) can affect the mechanical properties of zirconia, which is used to fabricate monolithic ceramic crowns.
The purpose of this in vitro study was to ...assess the changes in flexural strength of monolithic ceramic crowns fabricated from translucent zirconia due to surface glazing and LTD.
Sixty plates of zirconia (25×4×1.2 mm) were milled and sintered. They were classified into 4 groups according to glazing and LTD (n=15): control, glazing, LTD, and LTD after glazing. A 3-point flexural test was performed with a universal testing machine. X-ray diffraction (XRD) was used to observe changes in the crystal structures of each group, and field emission scanning electron microscopy was used to observe the sizes of the crystal grains. Two-way analysis of variance was used to evaluate the results of the flexural strength tests, and the Tukey honestly significant difference test was performed for post hoc analysis (α=.05).
The flexural strength showed significant differences due to glazing (P<.01). No significant differences were found due to LTD (P>.05). The crystal grain size increased with decreasing flexural strength of the specimens. XRD showed monoclinic phases in the groups subjected to LTD.
Glazing significantly reduced the flexural strength of translucent zirconia. LTD decreased the flexural strength of glazed translucent zirconia, but not to a significant extent.
Background:Extended dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation is frequently used for high-risk patients in real-world practice. However, there are limited data ...about the long-term efficacy of extended DAPT after percutaneous coronary intervention (PCI).Methods and Results:This study investigated 1,470 patients who underwent PCI. The study population was divided into 2 groups based on DAPT duration: guideline-based DAPT (G-DAPT; DAPT ≤12 months after PCI; n=747) and extended DAPT (E-DAPT; DAPT >12 months after PCI; n=723). The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCEs), defined as cardiac death, myocardial infarction (MI), repeat target vessel revascularization, or stroke. The median follow-up duration was 80.8 months (interquartile range 60.6–97.1 months). The incidence of MACCE was similar in the G-DAPT and E-DAPT groups (21.0% vs. 18.3%, respectively; P=0.111). However, the E-DAPT group had a lower incidence of non-fatal MI (hazard ratio HR 0.535; 95% confidence interval CI 0.329–0.869; P=0.011), and target lesion revascularization (HR 0.490; 95% CI 0.304–0.792; P=0.004), and stent thrombosis (HR 0.291; 95% CI 0.123–0.688; P=0.005). The incidence of bleeding complications, including major bleeding, was similar between the 2 groups (5.2% vs. 6.3%, respectively; P=0.471).Conclusions:Although E-DAPT after DES implantation was not associated with a reduced rate of MACCE, it was associated with a significantly lower incidence of non-fatal MI, TLR, and stent thrombosis.
CO2 emissions are a major contributor to global warming. Biomass combustion is one approach to tackling this issue. Biomass is used with coal combustion in thermal power plants or with blast furnaces ...(BFs) because it is a carbon-neutral fuel; therefore, biomass provides the advantage of reduced CO2 emissions. To examine the effect of co-firing on pulverized coal injection (PCI) in BFs, two coals of different ranks were blended with the biomass in different proportions, and then their combustion behaviors were examined using a laminar flow reactor (LFR). The PCI combustion primarily functions as a source of heat and CO to supply the upper part of the BF. To create a similar PCI combustion environment, the LFR burner forms a diffusion flat flame with an oxygen concentration of 26% with a flame temperature of ~2000–2250 K at a heating rate of 105 K/s. The combustion characteristics, such as the flame structure, burning coal particle temperature, unburned carbon (UBC), and CO and CO2 emissions were measured to evaluate their effect on PCI combustion. With the increase in the biomass blending ratio, the brightness of the volatile cloud significantly increased, and the particle temperature tended to decrease. The fragmentation phenomenon, which was observed for certain coal samples, decreased with the increase in the biomass blending ratio. In particular, with an increase in the biomass blending ratio, the optimum combustion point occurred, caused by the fragmentation of coal and volatile gas combustion of biomass.
The suicide rate in Korea was the highest among the member countries of the Organization for Economic Cooperation and Development(OECD) for 2013-2016 and 2018-2020. In korea, suicide was the leading ...cause of death among individuals aged 10-39, and the second leading cause of death for aged 40-59. Thus, this study aimed to examine the Werther effect of the suicides of three Korean idol singers (Jonghyun: December 18, 2017, Sulli: October 14, 2019, and Hara Gu: November 24, 2019).
The study conducted Poisson regression and used the cause-of-death statistics microdata from 2016 to 2020 provided by Statistics Korea. The case periods ranged from the day of the suicide of each celebrity to 10 weeks after. The control periods were all weeks from 2016 to 2020, excluding the case periods.
The suicide rates in Korea significantly increased by 1.21, 1.30, and 1.28 times after the deaths of Jonghyun, Sulli, and Hara Gu, respectively. The Werther effect was more evident in women than men. Suicide rate among individuals aged 10-29 years was greater than those for other age groups.
This study confirmed that the rate of copycat suicides increased after three celebrity singers in Korea died by suicide. Nevertheless, the rate of suicide after the suicide of the three celebrity singers was lower than those in previous studies in Korea.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This study aims to numerically analyze the ceramic and metallic monoliths as a catalyst substrate of selective catalytic reduction (SCR) system in marine applications. The representative elementary ...volume of each catalyst substrate was chosen and pressure drop through the volume was numerically calculated to estimate the parameters for the porous model. The fixed-bed experiment using a powder catalyst of 3V7MO/TiO
2
was conducted in the way to estimate the global one-step reaction kinetics. Thus, the NO conversion from both ceramic and metallic monolith catalysts was calculated by a porous model with a simplified reaction mechanism to numerically investigate the flow and thermal characteristics within the two types of catalyst substrate. As an extreme condition, an external heat loss with an ambient temperature of 300 K was set to the reactor wall. Predicted results indicate that the NO conversion performance of ceramic monolith is better in general due to the lower heat loss from the cold wall. However, it is found that there is a trade-off relationship between the residence time and the external heat loss. Heat management such as thermal insulation plays an essential role to maximize the benefits of using metallic monolith as a catalyst substrate for practical marine applications.
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