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Single-molecule magnetic tweezers deliver magnetic force and torque to single target molecules, permitting the study of dynamic changes in biomolecular structures and their interactions. Because the magnetic tweezer setups can generate magnetic fields that vary slowly over tens of millimeters—far larger than the nanometer scale of the single molecule events being observed—this technique can maintain essentially constant force levels during biochemical experiments while generating a biologically meaningful force on the order of 1–100 pN. When using bead–tether constructs to pull on single molecules, smaller magnetic beads and shorter submicrometer tethers improve dynamic response times and measurement precision. In addition, employing high-speed cameras, stronger light sources, and a graphics programming unit permits true high-resolution single-molecule magnetic tweezers that can track nanometer changes in target molecules on a millisecond or even submillisecond time scale. The unique force-clamping capacity of the magnetic tweezer technique provides a way to conduct measurements under near-equilibrium conditions and directly map the energy landscapes underlying various molecular phenomena. High-resolution single-molecule magnetic tweezerscan thus be used to monitor crucial conformational changes in single-protein molecules, including those involved in mechanotransduction and protein folding.

Symptomatic ganglion cysts within the knee joint are rare, and the mainstay of treatment for these cases has been surgical excision. We present a case of a ganglion cyst of the anterior cruciate ligament (ACL) treated with ultrasound-guided aspiration in an outpatient clinic. A 45-year-old woman presented to the hospital with posterior right knee pain after falling down. We were able to identify well circumscribed 2.2cm mass confined to ACL on Magnetic resonance imaging (MRI). We performed percutaneous needle aspiration of the ACL ganglion cyst under ultrasound (US) guidance. The patient's symptoms improved immediately after the procedure and she had no complications. Four weeks later, follow-up revealed that the patient's symptoms had disappeared. Six months later, a recurrence of a ganglion cyst was confirmed on follow-up and was treated in the same way.

Despite advances in resolving the structures of multi-pass membrane proteins, little is known about the native folding pathways of these complex structures. Using single-molecule magnetic tweezers, we here report a folding pathway of purified human glucose transporter 3 (GLUT3) reconstituted within synthetic lipid bilayers. The N-terminal major facilitator superfamily (MFS) fold strictly forms first, serving as a structural template for its C-terminal counterpart. We found polar residues comprising the conduit for glucose molecules present major folding challenges. The endoplasmic reticulum membrane protein complex facilitates insertion of these hydrophilic transmembrane helices, thrusting GLUT3's microstate sampling toward folded structures. Final assembly between the N- and C-terminal MFS folds depends on specific lipids that ease desolvation of the lipid shells surrounding the domain interfaces. Sequence analysis suggests that this asymmetric folding propensity across the N- and C-terminal MFS folds prevails for metazoan sugar porters, revealing evolutionary conflicts between foldability and functionality faced by many multi-pass membrane proteins.

Oxyapatite[Ca2Nd8(SiO4)6O2] glass-ceramics have been suggested as wasteforms for the immobilisation of rare-earth radioactive nuclides because of their high waste-loading capability and good chemical durability. In particular, a partitioning effect is predicted to contribute to an enhancement of corrosion resistance in glass-ceramics compared with that of conjugate glasses of the same composition. Because rare-earths are inherently insoluble nuclides, detection of changes in corrosion behavior between glass-ceramics and conjugate glasses under normal conditions is not easy. In this study, therefore, we revealed the partitioning effect by exposing glass-ceramics and glasses to solution of pH 2, 7 and 10 at 90 °C for 20 d. In addition, we proposed the corrosion mechanism for oxyapatite glass-ceramics under various corrosion conditions. Especially, the glassy phase dissolved first, followed by the oxyapatite phase during pH 7 corrosion.

This study presents a novel scheme to generate trimmed hexahedral meshes for the finite element analysis of solids with sharp edges and corners. An initial trimmed hexahedral mesh is created by cutting a background hexahedral grid with a geometric surface representing the solid boundary. Feature-preserving trimmed hexahedral elements are constructed by modifying the connectivity of initial trimmed hexahedral elements with feature nodes created at the sharp edges and corners interacting with the grid cells. A Laplacian mesh smoothing technique is employed to improve the shape quality of trimmed hexahedral elements without losing the sharp features. The polyhedral shape functions for feature-preserving trimmed hexahedral elements are effectively constructed based on the feature-based tetrahedral subdomains. The performance of the present method is investigated through the finite element analysis of structures with sharp features.

There have been no reports on mortality in patients with markedly elevated aspartate aminotransferase (AST) levels from non-hepatic causes to date. This study aimed to determine the etiologies of markedly elevated AST levels > 400 U/L due to non-hepatic causes and to investigate the factors associated with mortality in these cases. This retrospective study included 430 patients with AST levels > 400 U/L unrelated to liver disease at two centers between January 2010 and December 2021. Patients were classified into three groups according to etiology: skeletal muscle damage, cardiac muscle damage, and hematologic disorder. Binary logistic regression analysis was performed to evaluate the factors associated with 30-day mortality. The most common etiology for markedly elevated AST levels was skeletal muscle damage (54.2%), followed by cardiac muscle damage (39.1%) and hematologic disorder (6.7%). The 30-day mortality rates for the skeletal muscle damage, cardiac muscle damage, and hematologic disorder groups were 14.2%, 19.5%, and 65.5%, respectively. The magnitude of the peak AST level significantly correlated with 30-day mortality, with rates of 12.8%, 26.7%, and 50.0% for peak AST levels < 1000 U/L

This study analyzes how climate change affects the economy, society, and environment in South Korea. Then, the study explores the ways to strengthen capabilities that can alleviate climate change impacts. To find them, the study employs a system dynamics simulation method and builds a model with several sectors including the urban, rural, population, and social-environmental sectors. The study compares the size of climate change damages in rural and urban areas. The results with representative concentration path (RCP) 8.5 show that the size of climate change damage will continue to increase by 2050. The projected damages from the reduced industrial outputs in urban areas will be larger than that in rural areas. The results also show that the service sector will face stronger impacts from climate change than the manufacturing and agricultural sectors. However, the total size of damage in the rural areas will be bigger than that of the urban areas. It is because the size of reduced industrial outputs per capita in the rural areas is twice bigger than that of the urban areas. The climate change damage in the social and environmental sectors (including a loss of biodiversity and an increase in health costs) account for the largest part of the total damage. The study finally provides suggestions and policies that can improve the capabilities to reduce the climate change damages. One of the major suggestions of this study is that the increase in the climate change budget corresponding to the GDP growth can minimize the size of climate change impacts.

In this study, moving least square (MLS) shape functions are employed to reduce the cell-crossing error occurred in conventional material point method (MPM) when material particles pass through grid cell boundaries. The level of smoothness of MLS shape functions for mapping information from material particles to a background grid can be controlled by the support size of MLS weight functions. A simple method is proposed to reduce the computational cost for evaluating MLS shape functions at material particles by interpolating pre-computed MLS shape function values at sampling points in a grid cell. Numerical results show that the present method is very effective to reduce the cell-crossing error in MPM computations.

Antiferromagnetic spin waves have been predicted to offer substantial functionalities for magnonic applications due to the existence of two distinct polarizations, the right-handed and left-handed modes, as well as their ultrafast dynamics. However, experimental investigations have been hampered by the field-immunity of antiferromagnets. Ferrimagnets have been shown to be an alternative platform to study antiferromagnetic spin dynamics. Here we investigate thermally excited spin waves in ferrimagnets across the magnetization compensation and angular momentum compensation temperatures using Brillouin light scattering. Our results show that right-handed and left-handed modes intersect at the angular momentum compensation temperature where pure antiferromagnetic spin waves are expected. A field-induced shift of the mode-crossing point from the angular momentum compensation temperature and the gyromagnetic reversal reveal hitherto unrecognized properties of ferrimagnetic dynamics. We also provide a theoretical understanding of our experimental results. Our work demonstrates important aspects of the physics of ferrimagnetic spin waves and opens up the attractive possibility of ferrimagnet-based magnonic devices. Right- and left-handed spin-wave modes are identified in ferrimagnets, and their dynamics are revealed.

In this study, we present a novel finite element approach to simulate crack propagation in shell structures. A local spider-web mesh is placed at the tip of a crack propagating through a global background mesh. Interface shell elements with assumed natural strains are used to connect a non-matching interface between the background mesh and the local spider-web mesh. Interface shell elements are also employed for trimmed shell elements created by cutting shell elements with the crack line. Numerical simulation of crack propagation in shell structures can be easily performed by moving the local spider-web mesh with an incremental crack growth. Numerical experiments show that the present method is very efficient and effective to accurately simulate crack propagation in shell structures without significantly increasing computational burden and implementation complexity of remeshing process.

In this study, fatigue damage is combined with a cohesive zone model to simulate fatigue crack growth along the interface between dissimilar materials under repeated loadings. An evolution equation for fatigue damage is considered for the degradation of materials in a failure process zone. The potential-based Park–Paulino–Roesler cohesive model is employed to correctly consider mixed modes in the relationships between cohesive tractions and crack opening separations. Numerical examples show that the present method can predict properly fatigue crack growth along the interface between dissimilar materials under repeated loadings.

This study explores the impacts of temperature changes on electricity consumption in South Korea. In particular, the study estimates the impacts by separating them into the residential, commercial, industrial, and agricultural sectors. The study found that temperature changes affect the electricity consumption of all four sectors. However, the size and shape of impacts vary depending on the sector. While the commercial and industrial electricity consumption increase both in hot and cold temperatures, residential consumption increases only in hot temperatures. The agricultural sector shows that its consumption responds to cold temperatures more significantly than hot temperatures. These results suggest that the sectoral variations should be considered when predicting future electricity consumption. With an assumption of 2°C average temperature increases, the electricity consumption of residential, commercial, industrial, and agricultural sectors is projected to increase by 6%, 8%, 1%, and 4% in the summer season (July to September), respectively. In the spatial analysis, the annual consumption of residential and commercial sectors is projected to increase in most counties while the agricultural sector shows the opposite result. With 2°C and 5°C average temperature increases, the study found that total electricity consumption in August would increase by 4.1% (1.5[Formula: see text]TWh) and 11.3% (4.1[Formula: see text]TWh). This would create additional costs of $0.17 billion and $0.45 billion with an assumption that the average marginal cost of electricity in South Korea was 11 cents per kWh.

In this study, a resonance avoidance control algorithm was designed to address the tower resonance problem of a semi-submersible floating offshore wind turbine (FOWT) and the dynamic performance of the wind turbine, floater platform, and mooring lines at two exclusion zone ranges were evaluated. The simulations were performed using Bladed, a commercial software for wind turbine analysis. The length of simulation for the analysis of the dynamic response of the six degrees of freedom (DoF) motion of the floater platform under a specific load case was 3600 s. The simulation results are presented in terms of the time domain, frequency domain, and using statistical analysis. As a result of applying the resonance avoidance control algorithm, when the exclusion zone range was ±0.5 rpm from the resonance rpm, the overall performance of the wind turbine was negatively affected, and when the range was sufficiently wide at ±1 rpm, the mean power was reduced by 0.04%, and the damage equivalent load of the tower base side–side bending moment was reduced by 14.02%. The tower resonance problem of the FOWT caused by practical limitations in design and cost issues can be resolved by changing the torque control algorithm.

Standard consumer theory predicts that under block pricing, quantities consumed should bunch below block thresholds where marginal prices rise. However, researchers have previously found little or no evidence of bunching. In this study, I examine whether consumers respond to the marginal prices by using a different form of block pricing, one that includes both marginal price and fixed charge increases at the threshold, called increasing fixed-charge block pricing. Under this pricing schedule, the price increase at the threshold is more salient compared to the standard block pricing due to the increase in fixed charge. As a result, consumers are predicted to bunch below the thresholds and generate a zero density hole above the thresholds. I empirically test this by using the case in South Korea and find evidence that consumers tended to respond to price increase at the thresholds in 2005 and 2006. The considerable consumer bunching is observed around the thresholds. However, this evidence suddenly disappears after 2007 and never returned. While the reasons for this disappearance are not fully understood, the absence of consumer bunching suggests that consumers tend to respond to alternative pricing schedules rather than marginal price even with salient marginal price increases at the threshold.

In this study, a new polygonal shell element is developed to provide greater flexibility in mesh design of complex shell structures . Wachspress coordinates are used to construct shape functions for polygonal shell elements. An assumed covariant shear strain field with respect to the element natural coordinate system is defined by employing the mixed interpolation of tensorial components approach to avoid transverse shear locking in polygonal shell elements. Moreover, an assumed covariant membrane strain field is constructed by using characteristic geometry and displacement vectors defined on quadrilateral subdomains of polygonal shell elements to alleviate membrane locking due to the element curvature. Some benchmark shell problems are solved to evaluate the performance of the proposed polygonal shell elements. Numerical experiments show that they converge much better than triangular shell elements and comparable to quadrilateral shell elements.

This paper presents a new approach for level set based shape optimization using trimmed hexahedral meshes that geometrically conform to shape and topology changes during the optimization process. The marching cubes algorithm is employed to generate trimmed hexahedral meshes at each optimization iteration by splitting a regular background hexahedral mesh with the zero-isosurface of a level set function . A simple method is proposed to handle nonconforming polyhedral elements at the interface due to the face ambiguity arising in the marching cubes algorithm. The motion of the zero-isosurface of a level set function is obtained from the solution of the Hamilton–Jacobi transport equation using a normal velocity field defined on the regular background hexahedral mesh. Numerical results show that the present approach provides a natural and effective tool to solve shape optimization problems relying on explicitly discretized meshes of the shapes throughout the optimization process.