Prediction-hardness of acyclic conjunctive queries

AbstractA conjunctive query problem is a problem to determine whether or not a tuple belongs to the answer of a conjunctive query over a database. In this paper, a tuple, a conjunctive query and a database in relational database theory are regarded as a ground atom, a nonrecursive function-free definite clause and a finite set of ground atoms, respectively, in inductive logic programming terminology. An acyclic conjunctive query problem is a conjunctive query problem with acyclicity. Concerned with the acyclic conjunctive query problem, in this paper, we present the hardness results of predicting acyclic conjunctive queries from an instance with a j-database of which predicate symbol is at most j-ary. Also we deal with two kinds of instances, a simple instance as a set of ground atoms and an extended instance as a set of pairs of a ground atom and a description. We mainly show that, from both a simple and an extended instances, acyclic conjunctive queries are not polynomial-time predictable with j-databases (j⩾3) under the cryptographic assumptions, and predicting acyclic conjunctive queries with 2-databases is as hard as predicting DNF formulas. Hence, the acyclic conjunctive queries become a natural example that the equivalence between subsumption-efficiency and efficient pac-learnability from both a simple and an extended instances collapses

ジュニア キ ウンドウ センシュ ノ シンタイ ハツイク ト エイヨウ ソ トウ セッシュ リョウ ノ カカワリ

ジュニア期サッカー選手および野球選手の身体組成と栄養素等摂取状況の実態を把握し,ジュニア期運動選手の身体づくりにおける食事,栄養素等摂取の関わりについて考察することを目的とした。方法:15歳から17歳のサッカー選手(29名)および野球選手(42名)を対象に,生体インピーダンス法による身体組成測定と食物摂取頻度調査法による栄養素等摂取状況調査を実施した。結果:サッカー選手と野球選手はともに平均6.8年の競技歴があった。このとき,サッカー選手は15歳から17歳で身体組成および栄養素等摂取量に年齢の違いによる有意な差が見られなかったのに対し,野球選手は17歳で体重や体脂肪率が増加し,栄養素等摂取量も増加した。身体組成と栄養素等摂取量との関わりを検討した結果,ジュニア期運動選手においては除脂肪体重とエネルギー摂取量および炭水化物摂取量との間に有意な正の相関が見られた。結論:ジュニア期運動選手における除脂肪体重の増加には,炭水化物摂取の重要性が示唆された。The aim of this study was to estimate body composition and nutritional intakes, and to take basal data for dietary assessment of junior athletes. Methods:we estimated height, body weight, and body compositions such as body fat and lean body mass by bio-impedance methods, and nutritional intakes by food frequency questionnaire methods. Twenty-nine football players and forty-two baseball players 15yr to 17yr of age participated in this study. Results:Body mass, body fat percentage and nutritional intakes in 17yr significantly increased in baseball players compared with those in football players. In football players, there is no significant difference in body composition and in nutritional intake among the three different ages. On the other hand, in 17yr baseball players, body mass, muscle mass and body fat mass, and energy intakes were significantly higher than those of 16yr of age. There are significant correlations between lean body mass and intakes of energy or carbohydrate, but not protein or lipid. Conclusions:These results indicate that high school junior athletes might have suitable body composition and have done sufficient nutritional intakes, suggesting that it might be important for increasing lean body mass to have sufficient carbohydrate intakes

A Case of Inflammatory Lung Disease and Retroperitoneal Fibrosis Attributed to Systemic IgG4-related Disease

Recently, immunoglobulin (Ig) G4-related diseases such as autoimmune pancreatitis (AIP), sclerosingsialadenitis, retroperitoneal fibrosis, and sclerosing cholangitis have been reported. IgG4-related diseases arecharacterized by high serum IgG4 concentrations, sclerosing inflammation with numerous IgG4-positiveplasma cells, and steroid sensitivity, irrespective of their organ of origin. We describe a case of inflammatorylung disease and retroperitoneal fibrosis, suggested to involve IgG4. The patient was a 76-year-old man. Acomputed tomographic scan of the chest showed nodular air-space consolidation in the left upper lobe. Theserum IgG4 concentration was abnormally elevated, but there was no evidence of AIP. Bilateral hydronephrosisassociated with thickened soft tissue around the abdominal aorta had been diagnosed previously. Hehad undergone surgery, and retroperitoneal fibrosis was diagnosed histologically (hematoxylin and eosinstain). Histological examination of bronchoscopic specimens taken from the left S3 region showed mononuclear-cell infiltration of the fibrotic bronchial wall, including many IgG4-positive plasma cells. Specimens ofthe region affected by retroperitoneal fibrosis were retrospectively reanalyzed, and the cells were positivefor IgG4 on immunostaining, similar to the lung tissue. The patient responded to treatment with corticosteroids.In conclusion, the present case shared many clinical and clinicopathological similarities with systemicIgG4-related autoimmune disease. To our knowledge, however, this is the first reported case of inflammatorylung disease with retroperitoneal fibrosis in a patient with systemic IgG4-related autoimmune disease

シンキン マデ センツウ シタ イカイヨウ ノ イチ ボウケン レイ

症例は57歳,男性。脳硬塞にて入院中であったが,吐血をきたし内視鏡検査を施行した。胃体上部前壁に活動性潰瘍を認めた。潰瘍底は発赤した隆起を形成し心拍動に一致した動揺が認められた。内視鏡治療は断念し緊急手術の予定であったが,多量の出血をきたし手術に至らず出血性ショックで死亡した。剖検にて胃壁の漿膜から横隔膜を貫き心筋まで穿通した胃潰瘍と診断した。生前には心筋障害を示唆する臨床所見はなく,胃潰瘍の心への穿通は診断困難であった。消化性胃潰瘍の心への穿通は稀であり文献的考察を加え報告する。57-year-old man was admitted to our hospital because of cerebral infarction. After admission, he had hematemesis and underwent endoscopic examination. Gastric ulcer with oozing was noted at the anterior wall of the body. The ulcer bed was reddish and protruding with heart beat. Because of the difficulty of endoscopic hemostasis, we planned to perform urgent surgery for the bleeding ulcer. However, he died from hemorrhagic shock before surgery. At autopsy, penetration of gastric ulcer into the myocardium was found. It was difficult to make accurate diagnosis before death because of the lack of ECG findings to indicate myocardial damage. Herein, a rare case of penetration of gastric ulcer into the heart (pericardium and myocardium) has been reported

Rule-Generating Abduction for Recursive Prolog

The rule-generating abduction is a kind of abduction which generates a rule and proposes a hypothesis from a surprising fact . In general, there may exist infinitely many rules and hypotheses to explain such a surprising fact. Hence, we need to put some restriction on the class of rules. In rule-generating abduction, only one surprising fact is given. Hence, we also need to generalize the concept of a surprising fact. When we deal with such generalizations, we must avoid overgeneralization. It should be determined whether or not a generalization is overgeneral by an intended model. However, it is hard to give in advance such an intended model in our rule-generating abduction. Hence, in this paper we introduce a syntactical formulation of generalization, in which it can be determined whether or not a generalization is overgeneral by the forms of atoms and substitutions. On the other hand, by the restriction of rules, it suffices to consider only two types of terms, constants and lists, ..