Bounded Arithmetic in Free Logic

One of the central open questions in bounded arithmetic is whether Buss' hierarchy of theories of bounded arithmetic collapses or not. In this paper, we reformulate Buss' theories using free logic and conjecture that such theories are easier to handle. To show this, we first prove that Buss' theories prove consistencies of induction-free fragments of our theories whose formulae have bounded complexity. Next, we prove that although our theories are based on an apparently weaker logic, we can interpret theories in Buss' hierarchy by our theories using a simple translation. Finally, we investigate finitistic G\"odel sentences in our systems in the hope of proving that a theory in a lower level of Buss' hierarchy cannot prove consistency of induction-free fragments of our theories whose formulae have higher complexity

The Indian Ocean Dipole and Cholera Incidence in Bangladesh: A Time-Series Analysis

Background: It has been reported that the El Niño–Southern Oscillation (ENSO) influences the interannual variation of endemic cholera in Bangladesh. There is increased interest in the influence of the Indian Ocean dipole (IOD), a climate mode of coupled ocean–atmosphere variability, on regional ocean climate in the Bay of Bengal and on Indian monsoon rainfall. Objectives: We explored the relationship between the IOD and the number of cholera patients in Bangladesh, controlling for the effects of ENSO. Me t h o d s: Time-series regression was performed. Negative binomial models were used to estimate associations between the monthly number of hospital visits for cholera in Dhaka and Matlab (1993–2007) and the dipole mode index (DMI) controlling for ENSO index [NINO3, a measure of the average sea surface temperature (SST) in the Niño 3 region], seasonal, and interannual variations. Associations between cholera cases and SST and sea surface height (SSH) of the northern Bay of Bengal were also examined. Re s u l t s: A 0.1-unit increase in average DMI during the current month through 3 months before was associated with an increase in cholera incidence of 2.6 % [(95 % confidence interval (CI), 0.0–5.2; p = 0.05] in Dhaka and 6.9 % (95 % CI, 3.2–10.8; p < 0.01) in Matlab. Cholera incidence in Dhaka increased by 2.4 % (95 % CI, 0.0–5.0; p = 0.06) after a 0.1‑unit decrease in DMI 4–7 months before. Hospital visits for cholera in both areas were positively associated with SST 0–3 months before, after adjusting for SSH (p < 0.01). Con c l u s i o n s: These findings suggest that both negative and positive dipole events are associated with an increased incidence of cholera in Bangladesh with varying time lags. Key w o r d s: Bangladesh, cholera, El Niño–Southern Oscillation, Indian Ocean dipole, timeseries analysis. Environ Health Perspect 119:239–244 (2011). doi:10.1289/ehp.1002302 [Onlin

Treatment-related damage in elderly-onset ANCA-associated vasculitis: safety outcome analysis of two nationwide prospective cohort studies

Background It is not elucidated that there is treatment-related damage in elderly patients with antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis (AAV). Methods Elderly (≥ 75 years of age) patients were enrolled from two nationwide prospective inception cohort studies. The primary outcome was 12-month treatment-related Vasculitis Damage Index (VDI) score. Secondary outcomes included serious infections within 6 months, total VDI score, remission, and relapse. Patient characteristics and outcomes were compared across three different initial glucocorticoid (GC) dose groups: high-dose, prednisolone (PSL) ≥ 0.8 mg/kg/day; medium-dose, 0.6 ≤ PSL  Results Of the 179 eligible patients, the mean age was 80.0 years; 111 (62%) were female. The mean Birmingham Vasculitis Activity Score was 16.1. Myeloperoxidase-ANCA findings were positive in 168 (94%) patients, while proteinase 3-ANCA findings were positive in 11 (6%). The low-dose group was older and had higher serum creatinine levels than the other groups. There were no statistically significant intergroup differences in remission or relapse, whereas serious infection developed more frequently in the high-dose (29 patients [43%]) than the low-dose (13 patients [22%]) or medium-dose (10 patients [19%]) groups (p = 0.0007). Frequent VDI items at 12 months included hypertension (19%), diabetes (13%), atrophy and weakness (13%), osteoporosis (8%), and cataracts (8%). Logistic regression analysis revealed that GC dose at 12 months (odds ratio, 1.14; 95% confidence interval, 1.00–1.35) was a predictor for diabetes. Conclusion A reduced initial GC dose with rapid reduction might be required to ensure the safe treatment of elderly AAV patients

Exploratory classification of clinical phenotypes in Japanese patients with antineutrophil cytoplasmic antibody-associated vasculitis using cluster analysis

A novel patient cluster in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) may be identified in Japan. We performed multiple correspondence and cluster analysis regarding 427 clinically diagnosed AAV patients excluding eosinophilic granulomatosis with polyangiitis. Model 1 included the ANCA phenotype, items of the Birmingham Vasculitis Activity Score, and interstitial lung disease; model 2 included serum creatinine (s-Cr) and C-reactive protein (CRP) levels with model 1 components. In seven clusters determined in model 1, the ANCA-negative (n=8) and proteinase 3-ANCA-positive (n=41) groups emerged as two distinct clusters. The other five myeloperoxidase-ANCA-positive clusters were characterized by ear, nose, and throat (ENT) (n=47); cutaneous (n=36); renal (n=256), non-renal (n=33); and both ENT and cutaneous symptoms (n=6). Four clusters in model 2 were characterized by myeloperoxidase-ANCA negativity (n=42), without s-Cr elevation (1.3 mg/dL) with high CRP (>10 mg/dL) (n=71), or s-Cr elevation (>= 1.3 mg/dL) without high CRP (<= 10 mg/dL) (n=157). Overall, renal, and relapse-free survival rates were significantly different across the four clusters in model 2. ENT, cutaneous, and renal symptoms may be useful in characterization of Japanese AAV patients with myeloperoxidase-ANCA. The combination of s-Cr and CRP levels may be predictive of prognosis

ゲームリロン ニ モトヅイタ フクザツ ネットワーク ケイセイ ノ モデルカ

情報通信や社会学，生物学など多様な分野において，要素とその要素間の関係で構成されるネッ トワーク構造（トポロジ）が複雑ネットワークと呼ばれる特性を持っていることが明らかになって きている．多数の主体が自己組織的に複雑ネットワークを形成する原理を，構成主体の個人合理性 に落とし込むことで明らかにするために，我々はこれまでにゲーム理論に基づいた複雑ネットワー ク形成のモデル化を行い，その特性について分析してきた．本稿では，これまでの研究成果を概観 し，今後の展望について述べる．In various fields such as communication technology, sociology, and biology, it has been revealed that network structure（ topology） composed of elements and relationships of the elements has property of the complex networks. By the concept of individual rationality, in order to reveal why numerous individuals tend to self-organize complex networks, we have modeled complex networks formation based on game theory and analyzed their properties. In this paper, an overview of the research results and prospects are described