457 research outputs found
Graph 4-braid groups and Massey products
We first show that the braid group over a graph topologically containing no
-shape subgraph has a presentation related only by commutators. Then
using discrete Morse theory and triple Massey products, we prove that a graph
topologically contains none of four prescribed graphs if and only if its
4-braid groups is a right-angled Artin group.Comment: 23 pages, 4 figure
Templated native silk smectic gels
One aspect of the present invention relates to a method of preparing a fibrous protein smectic hydrogel by way of a solvent templating process, comprising the steps of pouring an aqueous fibrous protein solution into a container comprising a solvent that is not miscible with water; sealing the container and allowing it to age at about room temperature; and collecting the resulting fibrous protein smectic hydrogel and allowing it to dry. Another aspect of the present invention relates to a method of obtaining predominantly one enantiomer from a racemic mixture, comprising the steps of pouring an aqueous fibrous protein solution into a container comprising a solvent that is not miscible with water; sealing the container and allowing it to age at about room temperature; allowing the enantiomers of racemic mixture to diffuse selectively into the smectic hydrogel in solution; removing the smectic hydrogel from the solution; rinsing predominantly one enantiomer from the surface of the smectic hydrogel; and extracting predominantly one enantiomer from the interior of the smectic hydrogel. The present invention also relates to a smectic hydrogel prepared according to an aforementioned method
Templated Native Silk Smectic Gels
One aspect of the present invention relates to a method of preparing a fibrous protein smectic hydrogel by way of a solvent templating process, comprising the steps of pouring an aqueous fibrous protein solution into a container comprising a solvent that is not miscible with water; sealing the container and allowing it to age at about room temperature; and collecting the resulting fibrous protein smectic hydrogel and allowing it to dry. Another aspect of the present invention relates to a method of obtaining predominantly one enantiomer from a racemic mixture, comprising the steps of pouring an aqueous fibrous protein solution into a container comprising a solvent that is not miscible with water; sealing the container and allowing it to age at about room temperature; allowing the enantiomers of racemic mixture to diffuse selectively into the smectic hydrogel in solution; removing the smectic hydrogel from the solution; rinsing predominantly one enantiomer from the surface of the smectic hydrogel; and extracting predominantly one enantiomer from the interior of the smectic hydrogel. The present invention also relates to a smectic hydrogel prepared according to an aforementioned method
Templated Native Silk Smectic Gels
One aspect of the present invention relates to a method of preparing a fibrous protein smectic hydrogel by way of a solvent templating process, comprising the steps of pouring an aqueous fibrous protein solution into a container comprising a solvent that is not miscible with water; sealing the container and allowing it to age at about room temperature; and collecting the resulting fibrous protein smectic hydrogel and allowing it to dry. Another aspect of the present invention relates to a method of obtaining predominantly one enantiomer from a racemic mixture, comprising the steps of pouring an aqueous fibrous protein solution into a container comprising a solvent that is not miscible with water; sealing the container and allowing it to age at about room temperature; allowing the enantiomers of racemic mixture to diffuse selectively into the smectic hydrogel in solution; removing the smectic hydrogel from the solution; rinsing predominantly one enantiomer from the surface of the smectic hydrogel; and extracting predominantly one enantiomer from the interior of the smectic hydrogel. The present invention also relates to a smectic hydrogel prepared according to an aforementioned method
Enhanced spin density wave in LaOFeSb
We predict atomic, electronic, and magnetic structures of a hypothetical
compound LaOFeSb by first-principles density-functional calculations. It is
shown that LaOFeSb prefers a stripe-type antiferromagnetic phase (i.e., spin
density wave (SDW) phase) to the non-magnetic (NM) phase, with a larger Fe spin
moment and greater SDW-NM energy difference than those of LaOFeAs. The SDW
phase is found to favor the orthorhombic structure while the tetragonal
structure is more stable in the NM phase. In the NM-phase LaOFeSb, the
electronic bandwidth near the Fermi energy is reduced compared with LaOFeAs,
indicating smaller orbital overlap between Fe states and subsequently
enhanced intra-atomic exchange coupling. The calculated Fermi surface in the NM
phase consists of three hole and two electron sheets, and shows increased
nesting between two hole and two electron sheets compared with LaOFeAs.
Monotonous changes found in our calculated material properties of LaOFePn
(Pn=P, As, and Sb), along with reported superconducting properties of doped
LaOFeP and LaOFeAs, suggest that doped LaOFeSb may have a higher
superconducting transition temperature.Comment: 5 pages with 3 figures and 1 table, double colum
How do Investors in the Korean Stock Market React to Nuclear Threats from North Korea?
This article examines how investors react to nuclear threats from North
Korea on the South Korean stock market. To investigate the differences in
investor groups responses, we divide investors into three groups: domestic
individual, domestic institution and foreign investors. In addition, we
classify the nuclear threats into the one actual threat and the seven verbal
threats and compare trading activities of investors against those in the
peaceful period of 2004. The net-buying and LSV(1992) herding measures
are applied to examine investors trading behavior. Our results show that it
was only for the case of the actual threat that investors trades significantly
differed with the peaceful period. In addition, our results show that the
three investor groups reacted to the actual nuclear threat differently.
When the actual nuclear threat occurred, individuals sold, institutes and
foreigners bought stocks. Like in the peaceful period, institutes showed a
positive slope for lagged returns whereas individuals displayed a negative
slope. Foreigners, however, bought regardless of previous returns. Moreover,
LSV herding measure increased in all investor groups
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
Coprinus comatus Cap Inhibits Adipocyte Differentiation via Regulation of PPARĪ³ and Akt Signaling Pathway
This study assessed the effects of Coprinus comatus cap (CCC) on adipogenesis in 3T3-L1 adipocytes and the effects of CCC on the development of diet-induced obesity in rats. Here, we showed that the CCC has an inhibitory effect on the adipocyte differentiation of 3T3-L1 cells, resulting in a significant decrease in lipid accumulation through the downregulation of several adipocyte specific-transcription factors, including CCAAT/enhancer binding protein Ī², C/EBPĪ“, and peroxisome proliferator-activated receptor gamma (PPARĪ³). Moreover, treatment with CCC during adipocyte differentiation induced a significant down-regulation of PPARĪ³ and adipogenic target genes, including adipocyte protein 2, lipoprotein lipase, and adiponectin. Interestingly, the CCC treatment of the 3T3-L1 adipocytes suppressed the insulin-stimulated Akt and GSK3Ī² phosphorylation, and these effects were stronger in the presence of an inhibitor of Akt phosphorylation, LY294002, suggesting that CCC inhibited adipocyte differentiation through the down-regulation of Akt signaling. In the animal study, CCC administration significantly reduced the body weight and adipose tissue weight of rats fed a high fat diet (HFD) and attenuated lipid accumulation in the adipose tissues of the HFD-induced obese rats. The size of the adipocyte in the epididymal fat of the CCC fed rats was significantly smaller than in the HFD rats. CCC treatment significantly reduced the total cholesterol and triglyceride levels in the serum of HFD rats. These results strongly indicated that the CCC-mediated decrease in body weight was due to a reduction in adipose tissue mass. The expression level of PPARĪ³ and phospho-Akt was significantly lower in the CCC-treated HFD rats than that in the HFD obesity rats. These results suggested that CCC inhibited adipocyte differentiation by the down-regulation of major transcription factor involved in the adipogenesis pathway including PPARĪ³ through the regulation of the Akt pathway in 3T3-L1 cells and HFD adipose tissue
Single-Session Percutaneous Mechanical Thrombectomy for Acute and Subacute Deep Vein Thrombosis: Clinical Outcomes and Predictive Factors of Recurrence
Objectives: To evaluate the efficacy and safety of single-session percutaneous mechanical thrombectomy (PMT) for deep vein thrombosis (DVT), to compare clinical outcomes and recurrences between acute and subacute DVT, and to identify factors predicting recurrence. Materials and Methods: From January 2018 to March 2021, 100 consecutive patients (age: 64.64 Ā± 17.28 years; male, 42%) with symptomatic DVT who underwent single-session PMT were enrolled for this study. These patients were divided into an acute DVT group (< 14 days, n = 75) and a subacute DVT group (15ā28 days, n = 25). Results: A large-bore aspiration thrombectomy was used in 80 (80%) cases, Angiojet (Boston Scientific, Marlborough, MA, USA) device in one (1%) case, and a combination of both techniques in 19 (19%) cases. The anatomic success rate was 97% and the clinical success rate was 95%. There were no major complications. Clinical outcomes were not different between the two groups. The recurrence-free survival rate in the acute DVT group was significantly (p = 0.015) better than that in the subacute DVT group. The anatomic success (HR, 52.3; 95% CI, 3.82ā715.21; p = 0.003) and symptom duration (HR, 17.58; 95% CI, 1.89ā163.34; p = 0.012) were predictive factors associated with recurrence. Conclusions: Single-session PMT is safe and effective for immediate symptom relief in acute and subacute DVT patients. However, recurrence occurred more frequently in patients with subacute DVT than in those with acute DVT. Anatomic success of the procedure and duration of symptoms were independent predictors of DVT recurrence
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