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1.
The scale of shot, i.e. the apparent distance of the camera from the main subject of a scene, is one of the main stylistic and narrative functions of audiovisual products, conveying meaning and inducing the viewer’s emotional state. The statistical distribution of different shot scales in a film may be an important identifier of an individual film, an individual author, and of various narrative and affective functions of a film. In order to understand at which level shot scale distribution (SSD) of a movie might become its fingerprint, it is necessary to produce automatic recognition of shot scale on a large movie corpus. In our work we propose an automatic framework for estimating the SSD of a movie by using inherent characteristics of shots containing information about camera distance, without the need to recover the 3D structure of the scene. In the experimental investigation, the comparison of obtained results with manual SSD annotations proves the validity of the framework. Experiments conducted on movies by Michelangelo Antonioni taken from different stylistic periods (1950–57, 1960–64, 1966–75, 1980–82) show a strong similarity in shot scale distributions within each period, thus opening interesting research lines regarding the possible aesthetic and cognitive sources of such a regularity.  相似文献   
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Urethane (ethyl carbamate) which has long been used for commonly used drugs and has proven to be useful in the formation of products in every-day use, is volatile, and small amounts sublime spontaneously. Pregnant ICR mice were maintained in the vinyl chamber (45 liter) which was ventilated 4 times per hour. To inhale urethane gas, air was passed first through a glass bottle containing 500 g of crystalline urethane and then into the vinyl chamber. Concentration of the sublimed urethane gas in the chamber was 1.28 +/- 0.08 mg/l, and sublimed urethane gas produced significantly high incidence of chromosomal aberrations in the cells of whole embryo, when mice inhaled it for 48 h from day 9 to day 11 of pregnancy. High and significant incidence of chromosomal aberrations (36.0%) was detected in the embryo 3 h after urethane gas inhalation, but decreased to 5.3% at 24 h after exposure and showed no significant differences from controls after 48 h, while the incidence in bone marrow cells from the adult (pregnant) mice was lower (21.5%) at 3 h after exposure but a significant increase remained until 72 h after exposure. A majority of chromosomal aberrations was chromatid types. As a consequence of cellular damages by urethane gas inhalation during pregnancy, significantly high incidence of fetal deaths and congenital malformations (cleft palate, polydactyly, tail anomaly etc.) was induced in the offspring. Thus, we must be aware of the risk of volatile chemicals, because it is difficult to perceive and avoid hazardous exposure via respiration.  相似文献   
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Within the present work, the mechanism of bond is studied in composite grout/substrate specimens. Three types of tripartite (lime-pozzolan-cement) grouts are examined, combined with three substrates (two types of limestone and bricks). The interfaces between grout and substrate are characterized by means of mechanical tests in direct tension and shear. The in-time development of the tensile and shear bond strength is also investigated. In order to correlate the characteristics of the substrates and the obtained strengths of the interfaces, their surfaces and porosity are examined. The main conclusions of this study are that the studied tripartite grouts can develop tensile and shear bond strength comparable to Portland cement-based grouts, and that the value of the reached bond strength is governed mainly by the substrate characteristics and the binding properties of the grouts. The results of this project confirm the efficiency of tripartite lime-pozzolan-cement grouts with reduced Portland cement content for repair and strengthening of historic masonries.  相似文献   
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BACKGROUND: The incidence of anal cancer has increased in recent decades, particularly among women. To identify underlying risk factors, we conducted a population-based case-control study in Denmark and Sweden. METHODS: We conducted telephone interviews with 324 women and 93 men in whom invasive or in situ anal cancer was diagnosed between 1991 and 1994, 534 controls with adenocarcinoma of the rectum, and 554 population controls. The interviews covered a wide spectrum of possible risk factors for anal cancer. Odds ratios were calculated by logistic regression. Specimens of anal-cancer tissue and samples of rectal adenocarcinomas were tested for human papillomavirus (HPV) DNA with the polymerase chain reaction. RESULTS: Multivariate analysis revealed consistent and statistically significant associations between measures of sexual promiscuity and the risk of anal cancer in both men and women. There was a significant trend toward an association between higher numbers of partners of the opposite sex in women (P<0.001) and men (P<0.05) and strong associations with a variety of venereal diseases. In women, receptive anal intercourse, particularly before the age of 30 years, and venereal infections in the partner were also associated with an increased risk (odds ratios, 3.4 and 2.4, respectively). Fifteen percent of the men with anal cancer reported having had homosexual contact, as compared with none of the controls (P<0.001). High-risk types of HPV, notably HPV-16, were detected in 84 percent of the anal-cancer specimens examined, whereas all rectal-adenocarcinoma specimens tested were negative for HPV. CONCLUSIONS: Our study provides strong evidence that a sexually transmitted infection causes anal cancer. The presence of high-risk types of HPV, notably HPV-16 (which is known to cause cancer of the cervix), in the majority of anal-cancer tissue specimens suggests that most anal cancers are potentially preventable.  相似文献   
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We examined associations between lifestyle factors and subsequent risk of prostate cancer in a population-based case-control study. Information on smoking and alcohol habits, socioeconomic factors, marital status, family history, and sexual habits were obtained from a questionnaire and a face-to-face interview with 256 (74.6%) eligible patients and 252 (76.6%) selected controls, frequency matched by age and screened for prostate cancer with negative findings. Unconditional logistic regression was used to estimate the odds ratios (ORs). Risk was elevated among current smokers of cigarettes (OR, 1.8) and current users of hard liquor (OR, 1.4); however, the lack of dose-response trend for both of these exposures argues against a causal association. We found tentative evidence that early first intercourse, a larger number of sexual partners, and other indices of high sexual activity are associated with increased risk. Similarly, adult height, an indicator of nutrition during childhood and adolescence, was weakly positively associated with risk, although larger studies are needed to establish this link. Unmarried men had a lower risk than married men (OR, 0.3), and socioeconomic status did not appear to be strongly associated with prostate cancer. Men with a father who had prostate cancer had a more than 2-fold increased risk of prostate cancer, whereas those with a brother affected had about a 5-folk risk.  相似文献   
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Interviews were carried out with 423 women and 93 men with invasive or in situ anal cancer in Denmark and Sweden in a search for clues to the aetiology of this neoplasm. Patients with rectal adenocarcinoma (n = 534) and persons drawn from the background population (n = 554) served as controls. Multivariate logistic regression analyses confirmed previous observations of a strong association between either male homosexual experience or a history of anogenital warts and the risk for anal cancer. Moreover, hitherto unknown, but strong and consistent associations were observed between measures of high heterosexual activity and the risk for anal cancer among both sexes. Polymerase chain reaction analysis revealed human papilloma-virus DNA in the majority (88%) of anal cancer specimens but in none of 20 examined rectal adenocarcinomas. It is concluded that most anal cancers appear to be caused by sexually transmitted types of human papillomaviruses and, consequently, that anal cancer is a potentially preventable neoplasm.  相似文献   
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