199 research outputs found

    Extracting exact time bounds from logical proofs

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    Accurate evaluation of delays of combinatorial circuits is crucial in circuit verification and design. In this paper we present a logical approach to timing analysis which allows us to compute exact stabilization bounds while proving the correctness of the boolean behavior

    Snapshots generation via constructive logic

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    A software information system S allows users to store, retrieve and process information about the external world, typically in the form of a data base. We can differentiate two separate aspects in the data elaborated by S: the first concerns data types, while the second is related to the information on the external \u201creal world\u201d carried by the data. More precisely, a data type is a set of data together with the associated manipulations where the focus is on operations. In contrast, the other information carried by the data stored in S is strongly related to their meaning in the real world. The need for properly treating data according to their meaning is becoming increasingly important, due to the wide quantity of information exchanged on the Internet [5]. In this context, we are developing COOML [4] (Constructive Object Oriented Modeling Language), an OO specification language where the focus is on the information carried by data. The main features of COOML are: \u2013 a data model based on a predicative extension of the constructive intermediate logic E [3], following the Brower-Heyting-Kolmogorov interpretation of logical connectives; \u2013 a multi-layered structure, starting with the COOML logic layer, on top of which lies the problem domain logic, and finally the computation layer; \u2013 a data model based on the notion of \u201dpieces of information\u201d i : P, where i is a structured information (\u201dinformation value\u201d) giving constructive evidence for the truth of a specification P. We believe that COOML may have a role as an OO specification framework, and we are developing different prototypical tools. This work is in progress and more details are available at the COOML web page http://homepages.inf.ed.ac.uk/amomigl1/cooml. In this abstract, we focus on automatic snapshots generation [1]: in modeling languages (we concentrate on the UML [2] as the de-fact standard) a snapshot represents a system state (object diagram) and snapshots generation in the presence of OCL constraints has proved to be useful both for understanding a specification and verifying its consistency in the problem domain. In our approach, snapshots are represented by the pieces of information and our snapshots generation algorithm is driven by the constructive content of COOML specifications

    Snapshot generation in a constructive object-oriented modeling language

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    CooML is an object-oriented modeling language where specifications are theories in a constructive logic designed to handle incomplete information. In this logic we view snapshots as a formal counterpart of object populations, which are associated with specifications via the constructive interpretation of logical connectives. In this paper, we introduce the \u201csnapshot semantics\u201d of CooML and we describe a snapshot generation (SG) algorithm, which can be applied to validate specifications in the spirit of OCL-like constraints over UML models. Differently from the latter and from the standard BHK semantics, the logic allows us to exploit a notion of partial validation that is appropriate to encodings characterised by incomplete information. SG is akin to model generation in answer set programming. We show that the algorithm is sound and complete so that its successful termination implies consistency of the system

    Essential oils in the diet of young bulls: Effect on animal temperament.

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    Plant extracts and essential oils can be alternative products to antibiotics, because several plants produce secondary metabolites with antimicrobial properties. Additionally, they may act on the olfactory system, which sends signals to the central nervous system releasing endorphins that may affect the feeling of an animal''s welfare while altering an animal''s temperament. This study was conducted to evaluate the animal temperament of 40 young crossbred bulls (one-half Brown Swiss and one-half Nellore) 10 ± 2.2 mo old with an average BW of 219 ± 11.7 kg. Young bulls were randomly assigned to 1 of 5 diets: control, which had no clove or cinnamon; clove leaf included to supply 3, 500 mg/animal per day; clove leaf included to supply 7, 000 mg/animal per day; essential oil of leaf cinnamon to supply 3, 500 mg/animal per day; or essential oil of leaf cinnamon to supply 7, 000 mg/animal per day. The animal temperament was evaluated by calculating the chute score, exit score, and temperament score for periods (each 28 d during 6 periods) and among diets. The data were submitted to an ANOVA using GLM procedures with SAS version 9.0. The diet and period were considered fixed effects, whereas the animals were considered a random effect. Differences between means were evaluated using a Tukey test of 5% of significance. The addition of clove or cinnamon essential oils did not alter (P > 0.05) animal temperament. The analysis of temperament score (P = 0.55), chute score (P = 0.71), and exit score (P = 0.06) did not show significant differences among the diets. The exit score was similar among the 6 periods (1.57, 1.80, 2.98, 2.02, 2.73, and 2.66, respectively); however, chute score and temperament score were greater (P < 0.001) in the first period compared with other periods. The values for chute score were 1.85, 1.40, 1.35, 1.33, 1.20, 1.17, respectively, and the values for temperament score were 2.31, 1.81, 1.67, 1.69, 1.50, and 1.56, respectively, for periods 1 to 6. The results of this study suggest that clove and cinnamon essential oils can be added as an additive in high-grain finished diets without changing the animal temperament

    A constructive object oriented modeling language for information systems

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    One of the central aspects in an Information System is the meaning of data in the external world and the information carried by them. We propose a Constructive Object Oriented Modeling Language (COOML) for information systems, based on a constructive logic of pieces of information. The focus is on the definition of a data model suitable for organizing the information stored in OO systems. The underlying constructive logic supports a correct way of storing, exchanging and elaborating information

    Validation of photographs usage to evaluate meat visual acceptability of young bulls finished in feedlot fed with or without essential oils

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    Forty ½ Brown Swiss × ½ Nellore crossbred bulls were distributed into three experimental groups: CON – diet without addition of essential oils; CLO – diet with average 5, 000 mg/animal/day of clove essential oils and CIN – diet with average 5, 000 mg/animal/day of cinnamon essential oils to evaluate three methodologies of visual acceptability: with steaks directly in Trays and Sequential and Random photos. Seventeen consumers evaluated visual appearance of meat using a 9-point structured hedonic scale. CON group presented higher shelf-life than essential oils groups. Trays and Sequential scores were similar in the majority of days; thus digital images could be used to evaluate colour evolution. However, Random photos resulted in lower scores and slower acceptability decrease than Trays and Sequential photos (p < 0.05) among the second and fifth day of display. Random photos presented a lower and more constant standard deviation than Trays and Sequential photos (p < 0.01) indicating that this methodology promoted a higher standard situation for meat colour evaluation

    Camera-based window-opening estimation in a naturally ventilated office

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    Naturally ventilated offices enable users to control their environment through the opening of windows. Whilst this level of control is welcomed by users, it creates risk in terms of energy performance, especially during the heating season. In older office buildings, facilities managers usually obtain energy information at the building level. They are often unaware or unable to respond to non-ideal facade interaction by users often as a result of poor environmental control provision. In the summer months, this may mean poor use of free cooling opportunities, whereas in the winter space heating may be wasteful. This paper describes a low-cost, camera-based system to diagnose automatically the status of each window (open or closed) in a facade. The system is shown to achieve a window status prediction accuracy level of 90–97% across both winter and summer test periods in a case study building. A number of limitations are discussed including winter daylight hours, the impact of rain, and the use of fixed camera locations and how these may be addressed. Options to use this window-opening information to engage with office users are explored

    Prevalence, Outcome, and Prevention of Congenital Cytomegalovirus Infection in Neonates Born to Women With Preconception Immunity (CHILd Study)

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    Background. Human cytomegalovirus (HCMV) is the leading infectious cause of congenital disabilities. We designed a prospective study to investigate the rate, outcome, and risk factors of congenital CMV (cCMV) infection in neonates born to immune women, and the potential need and effectiveness of hygiene recommendations in this population.Methods. The study was composed of 2 sequential parts: an epidemiology (part 1) and a prevention (part 2) study. Performance of part 2 depended upon a cCMV rate >0.4%. Women enrolled in part 1 did not receive hygiene recommendations. Newborns were screened by HCMV DNA testing in saliva and cCMV was confirmed by urine testing.Results. Saliva swabs were positive for HCMV DNA in 45/9661 newborns and cCMV was confirmed in 18 cases. The rate of cCMV was .19% (95% confidence interval [CI]: .11-.29%), and 3 out of 18 infants with cCMV had symptoms of CMV at birth. Age, nationality, occupation, and contact with children were similar between mothers of infected and noninfected newborns. Twin pregnancy (odds ratio [OR]: 7.2; 95% CI: 1.7-32.2; P=.037) and maternal medical conditions (OR: 3.9; 95% CI: 1.5-10.1; P= .003) appeared associated with cCMV. Given the rate of cCMV was lower than expected, the prevention part of the study was cancelled.Conclusions. Newborns from women with preconception immunity have a low rate of cCMV, which appears to be mostly due to reactivation of the latent virus. Therefore, serological screening in childbearing age would be pivotal to identify HCMV-seropositive women, whose newborns have a low risk of cCMV

    Neuregulin 1 type III reduces severity in a mouse model of Congenital Hypomyelinating Neuropathy

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    Myelin sheath thickness is precisely regulated and essential for rapid propagation of action potentials along myelinated axons. In the peripheral nervous system, extrinsic signals from the axonal protein neuregulin 1 type III regulate Schwann cell fate and myelination. Here we ask if modulating neuregulin 1 type III levels in neurons would restore myelination in a model of congenital hypomyelinating neuropathy (CHN). Using a mouse model of CHN, we rescued the myelination defects by early overexpression of neuregulin 1 type III. Surprisingly, the rescue was independent from the upregulation of Egr2 or essential myelin genes. Rather, we observed the activation of MAPK/ERK and other myelin genes such as peripheral myelin protein 2 (Pmp2) and oligodendrocyte myelin glycoprotein (Omg). We also confirmed that the permanent activation of MAPK/ERK in Schwann cells has detrimental effects on myelination. Our findings demonstrate that the modulation of axon-to-glial neuregulin 1 type III signaling has beneficial effects and restores myelination defects during development in a model of CHN
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