• Advances in nano research
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• v.10 no.5
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• pp.461-470
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• 2021

Infection is one of the major mortality causes throughout the globe. Nuclear medicine plays an important role in diagnosis of deep infections such as osteomyelitis, arthritis infection, heart valve and heart prosthesis infections. Techniques such as labeled leukocytes are sensitive and selective for tracking the inflammations but they are not suitable for differentiating infection from inflammation. Anionic linear-globular dendrimer-G₂ was synthesized then conjugation to gemifloxacin antibiotic. The structures were identified by FT-IR, ¹H-NMR, C-NMR, LC-MS and DLS. The toxicity of gemifloxacin and dendrimer-gemifloxacin complex was compared by MTT test. Dendrimer-G₂-gemifloxacin was labeled by Technetium-99m and its in-vitro stability and radiochemical purity were investigated. In-vivo biodistribution and SPECT imaging were studied in a rabbit model. Identify and verify the structure of the each object was confirmed by FT-IR, ¹H-NMR, C-NMR and LC-MS, also, the size and charge of this compound were 128 nm and -3/68 mv respectively. MTT test showed less toxicity of the dendrimer-G₂-gemifloxacin than free gemifluxacin (P < 0.001). Radiochemical yield was > %98. Human serum stability was 84% up to 24 h. Biodistribution study at 50 min, 24 and 48 h showed that the complex is significantly absorbed by the intestine and accumulation in the lungs and affects them, finally excreted through the kidneys, biodistribution results are consistent with results from full image means of SPECT/CT technique.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.6
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• pp.473-480
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• 2021

In this paper, We analyze and present improvements to problems in software quality through Static Analysis for Open Source, which is widely used as the Flight Controller software for small unmanned aerial vehicle drones. MISRA coding rules, which are widely applied based on software quality, have been selected. Static analysis tools were used by LDRA tools certified international tools used in all industries, including automobiles, railways, nuclear power and healthcare, as well as aviation. We have identified some safety-threatening problems across the quality of the software, such as structure of open source modules, analysis of usage data, compliance with coding rules, and quality indicators (complexity and testability), and have presented improvements.

• Steel and Composite Structures
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• v.46 no.4
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• pp.471-483
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• 2023

This paper presents an analytical hyperbolic theory based on the refined shear deformation theory for mechanical stability analysis of the simply supported advanced composites plates (exponentially, sigmoidal and power-law graded) under triangular, trapezoidal and uniform uniaxial and biaxial loading. The developed model ensures the boundary condition of the zero transverse stresses at the top and bottom surfaces without using the correction factor as first order shear deformation theory. The mathematical formulation of displacement contains only four unknowns in which the transverse deflection is divided to shear and bending components. The current study includes the effect of the geometric imperfection of the material. The modeling of the micro-void presence in the structure is based on the both true and apparent density formulas in which the porosity will be dense in the mid-plane and zero in the upper and lower surfaces (free surface) according to a logarithmic function. The analytical solutions of the uniaxial and biaxial critical buckling load are determined by solving the differential equilibrium equations of the system with the help of the Navier's method. The correctness and the effectiveness of the proposed HyRPT is confirmed by comparing the results with those found in the open literature which shows the high performance of this model to predict the stability characteristics of the FG structures employed in various fields. Several parametric analyses are performed to extract the most influenced parameters on the mechanical stability of this type of advanced composites plates.

• Geomechanics and Engineering
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• v.31 no.5
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• pp.519-527
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• 2022

Shear failure in soil is the primary cause of most geotechnical structure failures or instability. Soil water content is a significant factor affecting soil shear strength. In this study, the shear strength of samples with different water contents was tested. The shear strength, cohesion, and internal friction angle decreased with increasing water content. Based on the variation of cohesion and internal friction angle, the water content zone was divided into a high-water content zone and low-water content zone with a threshold water content of 15.05%. Cohesion and internal friction angle have a good linear relationship with water content in both zones. Environmental Scanning Electron Microscopy (ESEM) test presented that the aggregates size of the compacted loess gradually increases with increasing water content. Meanwhile, the clay in the compacted loess forms a matric that envelops around the surface of the aggregates and fills the inter-aggregates pores. A quantitative analysis of bound water and free water under different water contents using a nuclear magnetic resonance (NMR) test was carried out. The threshold water content between bound water and free water was slightly below the plastic limit, which is consistent with the results of shear strength parameters. Combined with the T2 distributions obtained by NMR, one can define a T2 relaxation time of 1.58 ms as the boundary point for bound water distribution without free water. Finally, the effects of bound water and free water on shear strength parameters were analyzed using linear regression analysis.

• Journal of Veterinary Clinics
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• v.40 no.1
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• pp.16-24
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• 2023

This study aimed to compare complete ruptured tendon healing between two different repair methods using the Achilles tendon of New Zealand white rabbits. Thoracolumbar fascia (TF) padded Kessler suture, polypropylene mesh (PM) padded Kessler suture, and Kessler suture only were performed on the completely transected lateral gastrocnemius tendon, and biomechanical and histologic characteristics were assessed after 8 weeks. For biomechanical assessment, the tensile strength of each repaired tendon was measured according to the established methods. For histomorphometric analysis, hematoxylin and eosin staining for general histology, and Masson's trichrome (MT) staining for collagen fibers, Alcian blue (AB) staining for proteoglycans were performed and analyzed. Significant increases in tensile strength with remarkable decreases in the abnormalities against nuclear roundness, cell density, fiber structure, and fiber alignment and significant decreases in the mean number of infiltrated inflammatory cells and AB-positive proteoglycan-occupied regions with increases in MT-positive collagen fiber-occupied regions were demonstrated in the Kessler suture with PM or TF padding groups as compared to those of the Kessler suture group. Both of PM and TF provided potent tensile strength and supported healing with the evidence of histological examinations. This means that augmentation with PM is useful for repairing a completely ruptured Achilles tendon, without additional surgery for autograft material harvesting.

• Food Science of Animal Resources
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• v.42 no.2
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• pp.341-349
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• 2022

The objective of this study was to examine the effect of temperature abuse prior to cold storage on changes in quality and metabolites of frozen/thawed beef loin. The aerobic packaged samples were assigned to three groups: refrigeration (4℃) (CR); freezing (-18℃ for 6 d) and thawing (20±1℃ for 1 d), followed by refrigeration (4℃) (FT); temperature abuse (20℃ for 6 h) prior to freezing (-18℃ for 6 d) and thawing (20±1℃ for 1 d), followed by refrigeration (4℃) (AFT). FT and AFT resulted in higher volatile basic nitrogen (VBN) values than CR (p<0.05), and these values rapidly increased in the final 15 d. Cooking loss decreased significantly with an increase in the storage period (p<0.05). In addition, cooking loss was lower in the FT and AFT groups than in the CR owing to water loss after storage (p<0.05). A scanning electron microscope (SEM) revealed that frozen/thawed beef samples were influenced by temperature abuse in the structure of the fiber at 15 d. Metabolomic analysis showed differences among CR, FT, and AFT from partial least square discriminant analysis (PLS-DA) based on proton nuclear magnetic resonance (¹H NMR) profiling. The treatments differed slightly, with higher FT than AFT values in several metabolites (phenylalanine, isoleucine, valine, betaine, and tyrosine). Overall, temperature abuse prior to freezing and during thawing of beef loin resulted in accelerated quality changes.

• Food Science of Animal Resources
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• v.43 no.4
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• pp.712-720
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• 2023

Osteoporosis is a growing global health concern primarily associated with decreased estrogen in postmenopausal women. Recently, some strains of probiotics were examined for potential anti-osteoporotic effects. This study intended to evaluate the impacts of Lactiplantibacillus plantarum MGE 3038 strain (MGE 3038) in ovariectomized rats. For this purpose, twelve weeks old female Wistar rats (n=21; 250-300 g) were divided into 3 groups; ovariectomy (OVX) group, OVX/MGE 3038 group and Sham group (control). In these groups; two went through respective OVX and one had daily MGE 3038 administration through oral gavage. Prior to 16 weeks after OVX, we collected blood samples and extracted the tibiae. We scanned the extracted tibiae by in-vivo micro-computed tomography (micro-CT) and evaluated pathology by hematoxylin and eosin (H&E) and Masson's trichrome staining. The serum levels of C-telopeptide of type I collagen (CTX), osteocalcin (OC), and the receptor activator of nuclear factor-κB ligand (RANKL) were examined. The OVX/MGE 3038 group showed increases in bone mineral density, trabecular bone volume, trabecular number, and trabecular thickness (Tb.Th), and a decrease in trabecular spacing than the OVX group. However, OVX/MGE 3038 group and control group were measurably comparable in Tb.Th. Micro-CT, H&E, and Masson's trichrome findings exhibited increased preservation and maintenance of trabecular bone structure in the OVX/MGE 3038 group in comparison to the OVX group. In serum, the levels of CTX, OC and RANKL were significantly different between the OVX and OVX/MGE 3038 groups. Taken together, L. plantarum MGE 3038 could be helpful for the treatment of osteoporosis.

• Journal of Ginseng Research
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• v.47 no.4
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• pp.593-603
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• 2023

Background: Korean Red Ginseng is a major source of bioactive substances such as ginsenosides. Efficacy of red ginseng extract (RGE), which contains not only saponins but also various non-saponins, has long been studied. In the water-soluble component-rich fraction of RGE (WS), a byproduct generated in the process of extracting saponins from the RGE, we identified previously unidentified molecules and confirmed their efficacy. Methods: The RGE was prepared and used to produce WS, whose components were isolated sequentially according to their water affinity. The new compounds from WS were fractionized and structurally analyzed using nuclear magnetic resonance spectroscopy. Physiological applicability was evaluated by verifying the antioxidant and anti-inflammatory efficacies of these compounds in vitro. Results: High-performance liquid chromatography confirmed that the obtained WS comprised 11 phenolic acid and flavonoid substances. Among four major compounds from fractions 1-4 (F1-4) of WS, two compounds from F3 and F4 were newly identified in red ginseng. The analysis results show that these compound molecules are member of the maltol-structure-based glucopyranose series, and F1 and F4 are particularly effective for decreasing oxidative stress levels and inhibiting nitric oxide secretion, interleukin (IL)-1β and IL-6, and tumor necrosis factor-α. Conclusion: Our findings suggest that a few newly identified maltol derivatives, such as red ginseng-derived non-saponin in the WS, exhibit antioxidant and anti-inflammatory effects, making them viable candidates for application to pharmaceutical, cosmetic, and functional food materials.

• Progress in Superconductivity and Cryogenics
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• v.25 no.4
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• pp.70-74
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• 2023

The Small Punch Test (SPT) was developed to evaluate the softening and embrittlement of materials such as power plants and nuclear fusion reactors by taking samples in the field. Specimens used in the SPT are very thin and small disk-shaped compared to specimens for general tensile test, and thus have economic advantages in terms of miniaturization and repeatability of the test. The cryogenic SPT can also be miniaturized and has a significantly lower heat capacity than conventional universal test machines. This leads to reduced cooling and warm-up times. In this study, the cryogenic SPT was developed by modifying the existing room temperature SPT to be cooled by liquid nitrogen using a super bellows and a thermal insulation structure. Since the cryogenic SPT was first developed, basic experiments were conducted to verify the effectiveness of it. For the validation, aluminum alloy 6061- T6 specimens were tested for mechanical properties at room and cryogenic temperature. The results of the corrected tensile properties from the SPT experiment results were compared with known room temperature and cryogenic properties. Based on the correction results, the effectiveness of the cryogenic SPT test was confirmed, and the surface fracture characteristics of the material were analyzed using a 3d image scanner. In the future, we plan to conduct property evaluation according to the development of various alloy materials.

• Journal of the Korean Institute of Rural Architecture
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• v.26 no.2
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• pp.1-8
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• 2024

Carbon neutrality refers to a state in which there is no global increase in CO₂ emissions due to human activities. In Korea, for carbon neutrality, green remodeling of existing buildings and customized support tasks for zero energy in new buildings are presented. Germany is showing fundamental changes in energy supply, such as applying renewable energy and higher energy efficiency from nuclear and fossil fuels, which were the existing energy sources. In this study, how Germany establishes policies for carbon neutrality at each state level and the cases applied to increase the energy efficiency of the actually applied residential complexes are analyzed based on this. As a result of the case complex analysis, it was found that the construction direction was being promoted as a zero-energy complex or a carbon-neutral complex by gradually reducing the energy demand in buildings and supplying additional energy with new and renewable energy in the low-energy building distribution in the 1990s. In Germany's ecological complex, energy standards have been strengthened from low-energy architecture to plus-energy architecture over time, and annual heating energy consumption standards and heat transmittance rates for each structure have been achieved at a higher level. The results of this analysis will serve as basic data and derivation of applicable items when planning residential complex development and remodeling of existing buildings for the domestic carbon-neutral goal in the future.