The Williams Conjecture is false for irreducible subshifts

We show the Williams Conjecture is false for irreducible shifts of finite type by examining relative sign-gyration numbers of conjugacies between shifts with no points of period one or two.Comment: 14 pages, published versio

Non-stationarity of isomorphism between AF algebras defined by stationary Bratteli diagrams

We first study situations where the stable AF-algebras defined by two square primitive nonsingular incidence matrices with nonnegative integer matrix elements are isomorphic even though no powers of the associated automorphisms of the corresponding dimension groups are isomorphic. More generally we consider neccessary and sufficient conditions for two such matrices to determine isomorphic dimension groups. We give several examples.Comment: 16 page

On a Conjecture of Phadke and Thakare

AbstractWe prove the connectedness of the set of all nonzero bounded linear operators on a complex Hilbert space having a generalized inverse

A case of hyperacute postvaccinal encephalopathy after BNT162b2 nCoV-19 vaccine

The global severe acute respiratory syndrome coronavirus 2 pandemic contributed to the development of a large variety of vaccines, of which postvaccinal hyperacute encephalopathy is a very rare complication. Despite its rarity, if diagnosed properly, appropriate treatment can be rapidly applied. A healthy 53-year-old woman was admitted for a seizure on the day she received the second dose of the BNT 162b2 nCoV-19 vaccine. She subsequently developed irritability, which gradually worsened over several days. Cerebrospinal fluid analysis revealed mild pleocytosis and normal protein levels. Brain magnetic resonance imaging (MRI) revealed diffuse sulcal hyperintensity on the entire brain surface on fluid-attenuated inversion recovery images with meningeal enhancement. The patient was diagnosed with hyperacute postvaccinal encephalopathy and received immunosuppressive therapy with corticosteroids and therapeutic plasmapheresis. Fortunately, the patient responded to therapy, achieving almost complete recovery from the neurological symptoms, with only mild memory impairment remaining after 3 weeks. Based on the clinical presentation, electroencephalogram findings, and MRI, our patient developed hyperacute encephalopathy within 24 hours of vaccine administration, which we surmised from the temporal course of symptoms and brain imaging findings. Further studies are required to elucidate the pathogenesis of coronavirus disease 2019 vaccination-related encephalopathy

Polycyclic Aromatic Hydrocarbon Concentration Levels on the Korean Peninsula between 2006 and 2008

Concentrations of seven polycyclic aromatic hydrocarbon (PAH) compounds ) areas. The PAH values, when compared across seasons, tend to peak consistently during the winter (or spring) due to the active consumption of fossil fuels. The overall results of this study confirm that the pollution status of PAH compounds are clearly discernible not only between areas with different levels of anthropogenic activities, but also between periods with changes in environmental conditions

A randomized, phase II study of gefitinib alone versus nimotuzumab plus gefitinib after platinum-based chemotherapy in advanced non-small cell lung cancer (KCSG LU12-01)

We aimed to evaluate the efficacy of dual inhibition of epidermal growth factor receptor (EGFR) with nimotuzumab (EGFR monoclonal antibody) plus gefitinib (EGFR-tyrosine kinase inhibitor) in advanced non-small cell lung cancer (NSCLC) after platinum-based chemotherapy. An open label, randomized, phase II trial was conducted at 6 centers; 160 patients were randomized (1:1) to either gefitinib alone or nimotuzumab (200 mg, i. v. weekly) plus gefitinib (250 mg p. o. daily) until disease progression or intolerable toxicity. The primary endpoint was progression-free survival (PFS) at 3 months. Of the total 160 enrolled patients, 155 (77: gefitinib, 78: nimotuzumab plus gefitinib) received at least one dose and could be evaluated for efficacy and toxicity. The majority had adenocarcinoma (65.2%) and ECOG performance status of 0 to 1 (83.5%). The median follow-up was 22.1 months, and the PFS rate at 3 months was 48.1% in gefitinib and 37.2% in nimotuzumab plus gefitinib (P = not significant, NS). The median PFS and OS were 2.8 and 13.2 months in gefitinib and 2.0 and 14.0 months in nimotuzumab plus gefitinib. Combined treatment was not associated with superior PFS to gefitinib alone in patients with EGFR mutation (13.5 vs. 10.2 months in gefitinib alone, P=NS) or those with wild-type EGFR (0.9 vs. 2.0 months in gefitinib alone, P=NS). Combined treatment did not increase EGFR inhibition-related adverse events with manageable toxicities. The dual inhibition of EGFR with nimotuzumab plus gefitinib was not associated with better outcomes than gefitinib alone as a second-line treatment of advanced NSCLC (NCT01498562).

Normal Ambulatory 24-Hour Esophageal pH Values in Koreans -A Multicenter Study-

Ambulatory 24-hr esophageal pH monitoring is considered the gold standard for diagnosing gastroesophageal reflux disease. The aim of this study was to establish normal values for gastroesophageal acid exposure in healthy Koreans. Fifty healthy volunteers (24 males and 26 females; mean age, 45 yr) without reflux symptoms and without reflux esophagitis or hiatal hernia on upper endoscopy underwent ambulatory 24-hr esophageal pH monitoring after esophageal manometry. The 95th percentiles for the reflux parameters were: the percent total time pH <4, 3.7%; the percent upright time pH <4, 5.7%; the percent supine time pH <4, 1.0%; the number of reflux episodes with pH <4, 76.5; the number of reflux episodes with pH <4 for >5 min, 1.5; the duration of the longest episode, 12.5 min; and the composite score, 14.2. Age and gender were not associated with any of the pH parameters. In conclusion, physiological gastroesophageal reflux occurs in healthy Koreans. These normal esophageal pH values will provide reference data for clinical and research studies in Korea