Calabi-Yau Orbifolds and Torus Coverings

The theory of coverings of the two-dimensional torus is a standard part of algebraic topology and has applications in several topics in string theory, for example, in topological strings. This paper initiates applications of this theory to the counting of orbifolds of toric Calabi-Yau singularities, with particular attention to Abelian orbifolds of C^D. By doing so, the work introduces a novel analytical method for counting Abelian orbifolds, verifying previous algorithm results. One identifies a p-fold cover of the torus T^{D-1} with an Abelian orbifold of the form C^D/Z_p, for any dimension D and a prime number p. The counting problem leads to polynomial equations modulo p for a given Abelian subgroup of S_D, the group of discrete symmetries of the toric diagram for C^D. The roots of the polynomial equations correspond to orbifolds of the form C^D/Z_p, which are invariant under the corresponding subgroup of S_Ds. In turn, invariance under this subgroup implies a discrete symmetry for the corresponding quiver gauge theory, as is clearly seen by its brane tiling formulation.Comment: 33 pages, 5 figures, 7 tables; version published on JHE

Expression and Differential Responsiveness of Central Nervous System Glial Cell Populations to the Acute Phase Protein Serum Amyloid A

Acute-phase response is a systemic reaction to environmental/inflammatory insults and involves hepatic production of acute-phase proteins, including serum amyloid A (SAA). Extrahepatically, SAA immunoreactivity is found in axonal myelin sheaths of cortex in Alzheimer's disease and multiple sclerosis (MS), although its cellular origin is unclear. We examined the responses of cultured rat cortical astrocytes, microglia and oligodendrocyte precursor cells (OPCs) to master pro-inflammatory cytokine tumour necrosis factor (TNF)-\u3b1 and lipopolysaccaride (LPS). TNF-\u3b1 time-dependently increased Saa1 (but not Saa3) mRNA expression in purified microglia, enriched astrocytes, and OPCs (as did LPS for microglia and astrocytes). Astrocytes depleted of microglia were markedly less responsive to TNF-\u3b1 and LPS, even after re-addition of microglia. Microglia and enriched astrocytes showed complementary Saa1 expression profiles following TNF-\u3b1 or LPS challenge, being higher in microglia with TNF-\u3b1 and higher in astrocytes with LPS. Recombinant human apo-SAA stimulated production of both inflammatory mediators and its own mRNA in microglia and enriched, but not microglia-depleted astrocytes. Co-ultramicronized palmitoylethanolamide/luteolin, an established anti-inflammatory/neuroprotective agent, reduced Saa1 expression in OPCs subjected to TNF-\u3b1 treatment. These last data, together with past findings suggest that co-ultramicronized palmitoylethanolamide/luteolin may be a novel approach in the treatment of inflammatory demyelinating disorders like MS

Serum amyloid A primes microglia for ATP-dependent interleukin-1\u3b2 release

Acute-phase response is a systemic reaction to environmental/inflammatory insults and involves production of acute-phase proteins, including serum amyloid A (SAA). Interleukin-1\u3b2 (IL-1\u3b2), a master regulator of neuroinflammation produced by activated inflammatory cells of the myeloid lineage, in particular microglia, plays a key role in the pathogenesis of acute and chronic diseases of the peripheral nervous system and CNS. IL-1\u3b2 release is promoted by ATP acting at the purinergic P2X7 receptor (P2X7R) in cells primed with toll-like receptor (TLR) ligands

Analysis of Slab and Slab Heater Cover in a Compact Endless Cast and Rolling Mill Process using Finite Element Methods

Compact Endless cast and rolling Mill (CEM) processes were developed and used to fabricate steel products such as steel slabs. However, the coiling furnace in this process was very expensive, so a new layout was suggested. As the coiling furnace was removed, the interval among the slab heaters had to be increased. This led to a temperature drop in the slab. The temperature distribution of the slab impacts quality, so new layout was developed. This paper presents a Finite Element Method (FEM) simulation of thermal behavior in the slab employing slab heater covers. All of the simulation results were verified by comparing them with experimental results. The slab moving distance at which the temperature was saturated during the process was determined to consider the steady-state and analyze the temperature distribution of the slab and slab heater. Those results revealed that the efficiency of heat conservation increased by more than 50% using the slab heater cover. Finally, a sensitivity analysis of the slab heater cover was conducted with respect to the cover design. The effects of insulator thickness, the gap distance between the slab and cover, and material parameters such as density, and specific heat were investigated to optimize the design of the slab heater cover to produce the best quality slab.11Ysciescopuskc

Modification of the nanostructure of lignocellulose cell walls via a non-enzymatic lignocellulose deconstruction system in brown rot wood-decay fungi

Abstract Wood decayed by brown rot fungi and wood treated with the chelator-mediated Fenton (CMF) reaction, either alone or together with a cellulose enzyme cocktail, was analyzed by small angle neutron scattering (SANS), sum frequency generation (SFG) spectroscopy, Fourier transform infrared (FTIR) analysis, X-ray diffraction (XRD), atomic force microscopy (AFM), and transmission electron microscopy (TEM). Results showed that the CMF mechanism mimicked brown rot fungal attack for both holocellulose and lignin components of the wood. Crystalline cellulose and lignin were both depolymerized by the CMF reaction. Porosity of the softwood cell wall did not increase during CMF treatment, enzymes secreted by the fungi did not penetrate the decayed wood. The enzymes in the cellulose cocktail also did not appear to alter the effects of the CMF-treated wood relative to enhancing cell wall deconstruction. This suggests a rethinking of current brown rot decay models and supports a model where monomeric sugars and oligosaccharides diffuse from the softwood cell walls during non-enzymatic action. In this regard, the CMF mechanism should not be thought of as a “pretreatment” used to permit enzymatic penetration into softwood cell walls, but instead it enhances polysaccharide components diffusing to fungal enzymes located in wood cell lumen environments during decay. SANS and other data are consistent with a model for repolymerization and aggregation of at least some portion of the lignin within the cell wall, and this is supported by AFM and TEM data. The data suggest that new approaches for conversion of wood substrates to platform chemicals in biorefineries could be achieved using the CMF mechanism with >75% solubilization of lignocellulose, but that a more selective suite of enzymes and other downstream treatments may be required to work when using CMF deconstruction technology. Strategies to enhance polysaccharide release from lignocellulose substrates for enhanced enzymatic action and fermentation of the released fraction would also aid in the efficient recovery of the more uniform modified lignin fraction that the CMF reaction generates to enhance biorefinery profitability

A Pharmacokinetic/Pharmacodynamic Study of Esomeprazole Comparing a Dual Delayed-Release Formulation (YYD601) to a Conventional Formulation Following Multiple Administrations in Healthy Adult Subjects

Hae Won Lee,1 Woo Youl Kang,2 Ji Seo Park,1 Jae Hwa Lee,1 Jin Ju Park,1 Mi-Ri Gwon,1 Young-Ran Yoon,1 Sook Jin Seong1 1School of Medicine, Kyungpook National University and Department of Clinical Pharmacology and Therapeutics, Kyungpook National University Hospital, Daegu, 41944, Republic of Korea; 2Clinical Trial Dossier Evaluation Team, Innovative Products Support Department, National Institute of Food and Drug Safety Evaluation, Cheongju, 28159, Republic of KoreaCorrespondence: Young-Ran Yoon, Professor, School of Medicine, Kyungpook National University and Department of Clinical Pharmacology and Therapeutics, Kyungpook National University Hospital, 130 Dongdeok-Ro, Jung-gu, Daegu, 41944, Republic of Korea, Tel +82-53-420-4950, +82-53-420-5218, Email [email protected] Sook Jin Seong, Clinical Associate Professor, School of Medicine, Kyungpook National University and Department of Clinical Pharmacology and Therapeutics, Kyungpook National University Hospital, 130 Dongduk-Ro, Jung-gu, Daegu, 41944, Republic of Korea, Tel +82-53-200-6351, +82-53-420-5218, Email [email protected]: YYD601 is a new dual delayed-release formulation of esomeprazole, developed to enhance plasma exposure and prolong the duration of acid suppression.Purpose: This study aimed to evaluate the safety, pharmacokinetic (PK), and pharmacodynamic (PD) profiles of YYD601 20 mg following single and multiple oral administrations in healthy, fasting adult Koreans, and to compare these outcomes to those of the conventional esomeprazole 20 mg capsule.Methods: A randomized, open-label, two-period crossover study was conducted in 28 participants, who were divided into two treatment groups: one group received YYD601 20 mg, and the other received conventional esomeprazole 20 mg, once daily for five consecutive days. Blood samples for PK analysis were collected pre-dose and up to 24 hours post-dose. The primary PK parameters (AUClast and AUCτ) were evaluated. PD endpoints included integrated gastric acidity, percentage of time with intragastric pH > 4 over 24-hour and nighttime intervals, and percent change in serum gastrin levels after multiple dosing.Results: A total of 22 participants completed the study. YYD601 displayed more prolonged plasma concentration-time profiles than the conventional formulation, although the extent of the systemic exposure (AUC values) showed no statistically significant difference between the two formulations. With regard to the 24-hour gastric acid inhibition, YYD601 was comparable to the conventional formulation. The YYD601 showed a greater tendency for acid inhibition at night, as indicated by the percentage change of time with nocturnal acid breakthrough and other PD parameters. Both treatments were well tolerated, with no serious adverse events reported.Conclusion: Through extended systemic exposure of esomeprazole, YYD601 produces gastric acid suppression that is comparable to that of the conventional esomeprazole formulation, with a greater tendency to suppress acid at night. YYD601 20 mg was safe and well tolerated following single and multiple oral administrations, supporting its use as an effective alternative to conventional esomeprazole therapy.Clinical Trial Registry: http://clinicaltrials.gov, NCT03985319 (Date of registration: May 29, 2019; Study period: between July 2019 and March 2020).Keywords: esomeprazole, dual delayed-release formulation, pharmacokinetics, pharmacodynamic

Height outcomes in Korean children with idiopathic short stature receiving growth hormone treatment

OBJECTIVES: Growth hormone (GH) therapy's capacity to increase height velocity and height at the end of the study in children with idiopathic short stature (ISS) is controversial. We aimed to investigate the height standard deviation score (SDS) and height velocity of patients with ISS in Korea who received GH treatment. METHODS: We retrospectively reviewed and performed linear mixed model and survival analyses on data from 12 tertiary hospitals in Korea, including subjects diagnosed with ISS from January 2009 to September 2019, treated with GH therapy for more than 6 months, and who were at a pre-pubertal state at the time of diagnosis. RESULTS: We included 578 children (330 boys and 248 girls). The mean daily dose of GH in this study was 0.051 mg/kg, which was lower than the approved dose in Korea of 0.062 - 0.067 mg/kg. Height SDS was higher in patients who started treatment before the age of 6 years. The probability of reaching the target SDS (-1 SDS) from the beginning of treatment to 2-3 years after its start was higher in children starting treatment before the age of 6 years. The hazard ratio to reach the target SDS (-1 SDS) when using automatic pen or electronic devices was 1.727 times higher than that when using the needle and syringe device. CONCLUSION: ISS patients should start GH treatment at an early age, and even lower-than-recommended drug doses may be effective. The selection of automatic pen or electronic device can have a positive effect on reaching the target height SDS

Synthesis, Electrical Measurement, and Field Emission Properties of α-Fe2O3Nanowires

α-Fe2O3nanowires (NWs) were formed by the thermal oxidation of an iron film in air at 350 °C for 10 h. The rhombohedral structure of the α-Fe2O3NWs was grown vertically on the substrate with diameters of 8–25 nm and lengths of several hundred nm. It was found that the population density of the NWs per unit area (DNWs) can be varied by the film thickness. The thicker the iron film, the more NWs were grown. The growth mechanism of the NWs is suggested to be a combination effect of the thermal oxidation rate, defects on the film, and selective directional growth. The electrical resistivity of a single NW with a length of 800 nm and a diameter of 15 nm was measured to be 4.42 × 103 Ωcm using conductive atomic force microscopy. The field emission characteristics of the NWs were studied using a two-parallel-plate system. A low turn–on field of 3.3 V/μm and a large current density of 10−3 A/cm2(under an applied field of about 7 V/μm) can be obtained using optimal factors ofDNWsin the cathode

Summary of clinically diagnosed amniotic fluid embolism cases in Korea and disagreement with 4 criteria proposed for research purpose

Objective: This study aimed 1) to investigate the clinical characteristics of amniotic fluid embolism (AFE) cases clinically diagnosed by maternal fetal medicine (MFM) specialists in Korea, 2) to check the disagreement with 4 recently proposed criteria by the Society for Maternal-Fetal Medicine (SMFM) for research purpose, and 3) to compare maternal outcomes between cases satisfying all 4 criteria and cases with at least 1 missing criterion. Methods This study included 12 patients clinically diagnosed with AFE from 7 referral hospitals in Korea. We collected information, including maternal age, symptoms of AFE, the amount of transfusion, and maternal mortality. Results The median maternal age was 33 years (range, 28-40 years). Regarding symptoms, cardiovascular arrest, hypotension, respiratory compromise, clinical coagulopathy, and neurologic signs were observed in 41.7%, 83.3%, 83.3%, 100%, and 66.7% of the cases, respectively. Among the 12 cases, 5 women died and 2 suffered severe neurologic disability, showing an intact survival rate of 41.7%. Disagreement with all 4 criteria proposed by the SMFM was found in 66.7% of the cases, due to the lack of criteria for disseminated intravascular coagulation or strict onset time (<30 minutes after delivery). There was no difference in maternal mortality and the amount of transfusion between cases satisfying all 4 criteria and cases with at least 1 missing criterion. Conclusion Two-thirds of clinically confirmed AFE cases did not satisfy all 4 criteria proposed by the SMFM, despite similar rates of maternal mortality with cases satisfying all 4 criteria. Our study suggests that there may be some discrepancy between the clinical diagnosis of AFE and the recent diagnostic criteria proposed by the SMFM for research purpose

Prognostic Factors for Recurrence and Progression in Korean Non-Muscle-Invasive Bladder Cancer Patients: A Retrospective, Multi-Institutional Study

PURPOSE: To identify the prognostic factors related to tumor recurrence and progression in Korean patients with non-muscle-invasive bladder cancer (NMIBC). MATERIALS AND METHODS: Data were collected and analyzed for 2412 NMIBC patients from 15 centers who were initially diagnosed after transurethral resection of bladder tumor (TURBT) from January 2006 to December 2010. Using univariable and multivariable Cox proportional hazards models, the prognostic value of each variable was evaluated for the time to first recurrence and progression. RESULTS: With a median follow-up duration of 37 months, 866 patients (35.9%) experienced recurrence, and 137 (5.7%) experienced progression. Patients with recurrence had a median time to the first recurrence of 10 months. Multivariable analysis conducted in all patients revealed that preoperative positive urine cytology (PUC) was independently associated with worse recurrence-free survival [RFS: hazard ratio (HR) 1.56: p<0.001], and progression-free survival (PFS: HR 1.56: p=0.037). In particular, on multivariable analysis conducted for the high-risk group (T1 tumor/high-grade Ta tumor/carcinoma in situ), preoperative PUC was an independent predictor of worse RFS (HR 1.73: p<0.001) and PFS (HR 1.96: p=0.006). On multivariable analysis in patients with T1 high-grade (T1HG) cancer (n=684), better RFS (HR 0.75: p=0.033) and PFS (HR 0.33: p<0.001) were observed in association with the administration of intravesical Bacillus Calmette-Guerin (BCG) induction therapy. CONCLUSION: A preoperative PUC result may adversely affect RFS and PFS, particularly in high-risk NMIBC patients. Of particular note, intravesical BCG induction therapy should be administered as an adjunct to TURBT in order to improve RFS and PFS in patients with T1HG cancer