An Intelligent Man-Machine Dialogue System Based on AI Planning

We describe the modular architecture of a generic dialogue system that assists a user/operator in performing a task with a tool. This coaching system is named CALLIOPE after the Greek goddess of eloquence. It aims at being an active partner in an intelligent man-machine dialogue. The intelligent dimension of the coaching system is reflected by its ability to adapt to the user and the situation at hand. The CALLIOPE system contains an explicit user model and world model to situate its dialogue actions. A plan library allows it to follow loosely predetermined dialogue scenarios.The heart of the coaching system is an AI planning module, which plans a series of dialogue actions. We present a coherent set of three dialogue or speech actions that will make up the physical form of the man-machine communication.The use of the AI planning paradigm as a basis for man-machine interaction is motivated by research in various disciplines, as e.g., AI, Cognitive Science and Social Sciences. Starting from the man-man communication metaphor, we can view the thinking before speaking of a human communication partner as constructing an underlying plan which is responsible for the purposiveness, the organisation and the relevance of the communication.CALLIOPE has been fully implemented and tested on theoretical examples. At present, also three tailored versions of CALLIOPE are in operational use in different industrial application domains: operator support for remedying tasks in chemical process industry, operator support for a combined task of planning, plan execution and process control in the area of chemical process development, and thirdly decision support in production scheduling.     

Diffuse mesangial sclerosis: association with unreported congenital anomalies and placental enlargement

A case of diffuse mesangial sclerosis (DMS) associated with a number of undescribed congenital anomalies is reported. The occurrence of additional anomalies, especially ocular anomalies, is a common finding in DMS. However, neither megalocornea, Dandy-Walker malformation, postaxial hexadactyly, rocker-bottom feet, nor atrial septal defect, as observed in our patient, has been reported previously in association with DMS. This case might be considered an atypical manifestation of the Galloway-Mowat syndrome. In contrast to most cases of DMS, the patient revealed intrauterine proteinuria as the placenta was enlarged to 31% of birth weight. This case demonstrates that the large placenta, >25% of birth weight, is not only pathognomonic of the congenital nephrotic syndrome of the Finnish type but can also occur in DMS.     

Regularized phase tracker with isophase scanning strategy for analysis of dynamic interferograms of nonwetting droplets under excitation

The surface of a nonwetting droplet is separated from a solid surface by a continuous supply of a lubricating gas film within the apparent contact region. Under certain conditions, e.g., application of an external excitation force, the gas film thickness can decrease to a level where intermolecular forces cause the droplet to wet the surface. The thickness of the lubricating film can be measured by interferometry. Externally imposed oscillations change the shape of the film, leading to dynamic interference fringes that are recorded with a high-speed CCD camera. We propose a spatiotemporal analysis of the interference patterns based on the regularized phase-tracker method. This well-known method minimizes a cost function to estimate the absolute phase of a single element in the interferogram. A proper scanning method along all elements of the interferogram is necessary to avoid phase estimation errors that will propagate throughout the entire continuous phase image of interest. The scanning method we propose traces along contours of constant phase in the interferogram and does not require segmentation of the interferogram in dark and bright fringes. Results in the form of dynamic height profiles of droplets under excitation obtained by this method are presented.     

Challenging Google Search filter bubbles in social and political information: Disconforming evidence from a digital methods case study

This article engages in the debate on supposed online ‘filter bubbles’ by analysing a panel of Google users’ search results on a standardized set of socio-politically themed search queries. In general, the query results appear to be dominated by mainstream media sources, followed at a large distance by civil society and government resources. By means of mixed model regression analyses, with the prominence of different source types in the search results as dependent variables, it was tested whether search results vary across Google Search users. The results indicate that the inclusion of participants as a random effect does not explain variance when controlling for the different query keywords and the time at which the queries were ran. Hence, this study does not support the occurrence of ‘filter bubbles’ in Google Search results in the context of social and political information.     

Diagnostic value of immunostaining for tryptase in patients with mastocytosis

The term "mastocytosis" is used to describe a heterogeneous group of disorders characterized by abnormal growth and accumulation of mast cells (MCs). Cutaneous and systemic variants exist. Systemic mastocytosis may show an indolent or malignant clinical course. In malignant mastocytosis (MM), the diagnosis often is missed because the MCs are morphologically abnormal and lack metachromatic granules or the underlying histologic picture is complex. The cytoplasmic serine protease tryptase is produced by MCs and is thought to be expressed at all stages of MC maturation. To assess the diagnostic value of tryptase staining in mastocytosis, tissue sections from 93 patients with mastocytosis, including MM (n = 37), systemic indolent mastocytosis (n = 47), urticaria pigmentosa (n = 5), MC leukemia (n = 2), and solitary skin mastocytoma (n = 2) were stained with the antitryptase antibody G3. The results were compared with those of Giemsa and chloroacetate esterase (CAE) staining. Using antitryptase antibody G3, MC infiltrates were identified in all patients examined, including those with MM (37 of 37), and virtually all the neoplastic MCs (> 95%) appeared to react with G3. In MM, significantly fewer MCs were positive in Giemsa (54.5%; p < 0.05) and CAE (78.8%; p < 0.05). Moreover, G3 produced clear diagnostic staining in all cases of MM, but the proportion of cases with clear diagnostic results (> 10% of neoplastic cells positive) was considerably lower with Giemsa (48.6%; p < 0.05) and CAE (75.7%; p < 0.05) staining. By contrast, tryptase, Giemsa, and CAE produced diagnostic staining of MCs in virtually all cases of systemic indolent mastocytosis, urticaria pigmentosa, and solitary skin mastocytoma. In systemic mastocytosis, survival was significantly reduced in cases with Giemsa-/tryptase+ or CAE-/tryptase+ tumor cells compared to those cases with Giemsa+ or CAE+ MC infiltrates (p < 0.001).     

Pulmonary tuberculosis in the adult in a low prevalence area: is the radiological presentation changing?

BACKGROUND AND OBJECTIVE: To investigate the efficacy, predictability, stability, and safety of photorefractive keratectomy (PRK) with scanning spot ablation for the treatment of myopia of less than -6.0 D. PATIENTS AND METHODS: Twenty eyes of 20 patients (11 men, 9 women) were enrolled into the study. The mean age was 26.2 +/- 5.4 years. Mean spherical equivalent myopia was -3.53 +/- 1.13 D, ranging from -2.25 to -6.00 D. Patients underwent excimer laser PRK for the treatment of myopia. Follow-up time was at least 24 months in all patients. RESULTS: Mean spherical equivalent refraction was +0.84 +/- 0.99 D at 1 month, +0.19 +/- 0.54 at 3 months, -0.01 +/- 0.53 at 12 months, and -0.13 +/- 0.50 at 24 months. There was a mean regression of 0.65 D between 1 and 3 months. At 24 months, 16 (80%) of the eyes remained within +0.50 D of emmetropia and 18 (90%) of the eyes remained within +/- 1.0 D of emmetropia. Nineteen (95%) of the eyes had uncorrected visual acuity of 20/40 or better. The mean corneal haze score was maximum at 3 months (0.88 +/- 0.22). There was no clinically significant corneal haze (greater than 2+). One eye (5%) lost 2 or more lines of best-corrected visual acuity. CONCLUSION: Excimer laser PRK with the scanning spot ablation technique is effective, predictable, stable, and safe for the treatment of myopia of less than -6.0 D.     

Nanoarrays: a method for performing enzymatic assays

Conventional enzymatic assays for alcohol dehydrogenase, pyruvate kinase, and enolase performed in 96-well microtiter plates were compared with assays monitored in 25-well nanoarrays. All miniaturized reactions could be performed in maximum volumes of 6.3-8 nL and were read out with a conventional fluorescence microscope system equipped with a scientific grade CCD camera. Substrate and cofactor were already present inside the wells after having been presprayed, or they were applied in solution to the wells of the nanoarray shortly before the assays started. For all of the assays, commercially available enzymes and enzymes present in cell-free extracts were used. Assays carried out in premixed nanoarrays gave results comparable to those performed in presprayed nanoarrays. Enzyme activities determined in nanoarrays by using two different methods were in good agreement with assays performed in microtiter plates. Also, good correspondence was found between expected and observed enzyme levels. In short, enzymatic assays performed in premixed and in particular in presprayed nanoarrays are a promising low-volume and low-reagent- and sample-consuming alternative to current methodology and could find applications in many different areas of analytical chemistry.     

MGOUN1 and MGOUN2: two genes required for primordium initiation at the shoot apical and floral meristems in Arabidopsis thaliana

We report two new recessive mutations in Arabidopsis, mgoun1 and mgoun2 which cause a reduction in the number of leaves and floral organs, larger meristems and fasciation of the inflorescence stem. Although meristem structure is affected in the mutants, we provide evidence that its overall organisation is normal, as shown by the expression patterns of two meristem markers. Microscopical analyses suggest that both mutations affect organ primordia production. mgo1 strongly inhibits leaf production in a weak allele of shoot meristemless, stm-2. In addition, mgo1 and 2 severely reduce the ability of the fasciata1 and 2 mutants to initiate organs, although meristem formation per se was not inhibited. The strong allele, stm-5, is epistatic to mgo1, showing that the presence of meristematic cells is essential for MGO1 function. These results suggest a role for the MGO genes in primordia initiation although a more general role in meristem function can not be excluded. We describe a form of fasciation which is radically different from that described for clavata, which is thought to have an increased size of the meristem centre. Instead of one enlarged central meristem mgo1 and 2 show a continuous fragmentation of the shoot apex into multiple meristems, which leads to the formation of many extra branches. The phenotype of mgo1 clv3 and mgo2 clv3 double mutants suggest that the MGO and CLV genes are involved in different events. In conclusion, our results reveal two new components of the regulatory network controlling meristem function and primordia formation. A model for MGO genes is discussed.     

Open hypermedia as user controlled meta data for the Web

This paper introduces an approach to utilise open hypermedia structures such as links, annotations, collections and guided tours as meta data for Web resources. The paper introduces an XML based data format, called Open Hypermedia Interchange Format, OHIF, for such hypermedia structures. OHIF resembles XLink with respect to its representation of out-of-line links, but it goes beyond XLink with a more rich set of structuring mechanisms, including e.g. composites. Moreover OHIF includes an addressing mechanisms (LocSpecs) that goes beyond XPointer and URL in its ability to locate non-XML data segments. By means of the Webvise system, OHIF structures can be authored, imposed on Web pages, and finally linked on the Web as any ordinary Web resource. Following a link to an OHIF file automatically invokes a Webvise download of the meta data structures and the annotated Web content will be displayed in the browser. Moreover, the Webvise system provides support for users to create, manipulate, and share the OHIF structures together with custom made Web pages and MS Office 2000 documents on WebDAV servers. These Webvise facilities goes beyond earlier open hypermedia systems in that it now allows fully distributed open hypermedia linking between Web pages and WebDAV aware desktop applications. The paper describes the OHIF format and demonstrates how the Webvise system handles OHIF. Finally, it argues for better support for handling user controlled meta data, e.g. support for linking in non-XML data, integration of external linking in the Web infrastructure, and collaboration support for external structures and meta-data.