409 research outputs found
EFFECT OF SEAT TUBE ANGLE ON THE WORK EFFICIENCY OF LOWER LIMB MUSCLES DURING CYCLING
The effect of seat tube angle (STA) on work efficiency at lower limb muscle was evaluated during a pedal rotation using inverse dynamic model. Since the target is not professional cyclist, the various seat tube angles of 78, 68, 58 and 48 degrees was
investigated. Cycling simulation was performed at 250W and 60rpm. The works of individual muscle of lower limb and the total work was estimated. The result shows that the total work of single leg at seat tube angles of 78, 68, 58 and 48 degrees were
168.1(J), 167.9(J), 168.9(J) and 170.8(J) respectively. In conclusion, the exertion of lower limb for delivering same amount of work to the crank is the smallest at around 72 degree of seat tube angle which mean work efficiency of lower limb is the greates
Inverse Design of Terahertz Nanoresonators through Physics-Informed Machine Learning
The rapid development of 6G communications using terahertz (THz)
electromagnetic waves has created a demand for highly sensitive THz
nanoresonators capable of detecting these waves. Among the potential
candidates, THz nanogap loop arrays show promising characteristics but require
significant computational resources for accurate simulation. This requirement
arises because their unit cells are 10 times smaller than millimeter
wavelengths, with nanogap regions that are 1,000,000 times smaller. To address
this challenge, we propose a rapid inverse design method for terahertz
nanoresonators using physics-informed machine learning, specifically employing
double deep Q-learning combined with an analytical model of the THz nanogap
loop array. Through approximately 200,000 iterations in about 39 hours on a
middle-level personal computer (CPU: 3.40 GHz, 6 cores, 12 threads, RAM: 16 GB,
GPU: NVIDIA GeForce GTX 1050), our approach successfully identifies the optimal
structure, resulting in an experimental electric field enhancement of 32,000 at
0.2 THz, 300% stronger than previous achievements. By leveraging our analytical
model-based approach, we significantly reduce the computational resources
required, providing a viable alternative to the impractical numerical
simulation-based inverse design that was previously impractical
Glutaminase 1 inhibition reduces thymidine synthesis in NSCLC
AbstractWe found that non-small cell lung cancer (NSCLC) is remarkably sensitive to the regulation of glutamine supply by testing the metabolic dependency of 11 cancer cell lines against regulation of glycolysis, autophagy, fatty acid synthesis, and glutamine supply. Glutamine is known as a key supplement of cancer cell growth that is converted to α-ketoglutarate for anabolic biogenesis via glutamate by glutaminase 1 (GLS1). GLS1 inhibition using 10 μM of bis-2-(5-phenylacetamido-1,3,4-thiadiazol-2-yl)ethyl sulfide (BPTES) showed about 50% cell growth arrest by SRB assay. By testing the synergistic effects of conventional therapeutics, BPTES combined with 5-fluorouracil (5-FU), an irreversible inhibitor of thymidylate synthase, significant effects were observed on cell growth arrest in NSCLC. We found that GLS1 inhibition using BPTES reduced metabolic intermediates including thymidine and carbamoyl phosphate. Reduction of thymidine and carbamoyl-phosphate synthesis by BPTES treatment exacerbated pyrimidine supply by combination with 5-FU, which induced cell death synergistically in NSCLC
Small and Medium Amplitude Oscillatory Shear Rheology of Model Branched Polystyrene (PS) Melts
Linear and nonlinear rheological properties of model comb polystyrenes (PS) with loosely to densely grafted architectures were measured under small and medium amplitude oscillatory shear (SAOS and MAOS) flow. This comb PS set had the same length of backbone and branches but varied in the number of branches from 3 to 120 branches. Linear viscoelastic properties of the comb PS were compared with the hierarchical model predictions. The model underpredicted zero-shear viscosity and backbone plateau modulus of densely branched comb with 60 or 120 branches because the model does not include the effect of side chain crowding. First- and third-harmonic nonlinearities reflected the hierarchy in the relaxation motion of comb structures. Notably, the low-frequency plateau values of first-harmonic MAOS moduli scaled with M (total molecular weight), reflecting dynamic tube dilution (DTD) by relaxed branches. Relative intrinsic nonlinearity Q exhibited the difference between comb and bottlebrush via no low-frequency Q peak of bottlebrush corresponding to backbone relaxation, which is probably related to the stretched backbone conformation in bottlebrush
A Korean Family with an Early-Onset Autosomal Dominant Macular Dystrophy Resembling North Carolina Macular Dystrophy
Plexiform Angiomyxoid Myofibroblastic Tumor of the Stomach: A Case Report
Plexiform angiomyxoid myofibroblastic tumor (PAMT) is a recently described mesenchymal tumor of the stomach. We report the first case of PAMT in Korea. A 52-yr-old man underwent esophagogastroduodenoscopy due to dyspepsia for 2 yr. There was a submucosal mass with small mucosal ulceration in the gastric antrum. The tumor measured 3.5 × 2.3 cm in size and showed multinodular plexiform growth pattern of bland-looking spindle cells separated by an abundant myxoid or fibromyxoid matrix rich in small thin-walled blood vessels. The tumor cells were negative for CD117 (c-KIT), CD34 and S-100 protein, but diffusely positive for smooth muscle actin consistent with predominant myofibroblastic differentiation. The patient is doing well without recurrence or metastasis for 5 months after surgery. Although there have been limited follow-up data, PAMT is regarded as a benign gastric neoplasm with histological and immunohistochemical charateristics distinguished from gastrointestinal stromal tumor and other mesenchymal tumors of the stomach
Foreign Body Granulomas Simulating Recurrent Tumors in Patients Following Colorectal Surgery for Carcinoma: a Report of Two Cases
We report here two cases of foreign body granulomas that arose from the pelvic wall and liver, respectively, and simulated recurrent colorectal carcinomas in patients with a history of surgery. On contrast-enhanced CT and MR images, a pelvic wall mass appeared as a well-enhancing mass that had invaded the distal ureter, resulting in the development of hydronephrosis. In addition, a liver mass had a hypointense rim that corresponded to the fibrous wall on a T2-weighted MR image, and showed persistent peripheral enhancement that corresponded to the granulation tissues and fibrous wall on dynamic MR images. These lesions also displayed very intense homogeneous FDG uptake on PET/CT
Effect Of Nitric-Oxide Post-Oxidation Annealing On High-Temperature Oxidized 4H SiC.
Metal-Oxide-Semiconductor FETs using 4H-SiC have been investigated intensively because 4H-SiC semiconductor has excellent physical properties for power-device applications
A wearable multiplexed silicon nonvolatile memory array using nanocrystal charge confinement
Strategies for efficient charge confinement in nanocrystal floating gates to realize high-performance memory devices have been investigated intensively. However, few studies have reported nanoscale experimental validations of charge confinement in closely packed uniform nanocrystals and related device performance characterization. Furthermore, the system-level integration of the resulting devices with wearable silicon electronics has not yet been realized. We introduce a wearable, fully multiplexed silicon nonvolatile memory array with nanocrystal floating gates. The nanocrystal monolayer is assembled over a large area using the Langmuir-Blodgett method. Efficient particle-level charge confinement is verified with the modified atomic force microscopy technique. Uniform nanocrystal charge traps evidently improve the memory window margin and retention performance. Furthermore, the multiplexing of memory devices in conjunction with the amplification of sensor signals based on ultrathin silicon nanomembrane circuits in stretchable layouts enables wearable healthcare applications such as long-term data storage of monitored heart rates.
- …