Consider a database that represents information about moving objects and their location. For example, for a database representing the location of taxi-cabs a typical query may be: retrieve the free cabs that are currently within 1 mile of 33 N. Michigan Ave., Chicago (to pickup a customer). In the military, moving objects database applications arise in the context of the digital battlefield, and in the civilian industry they arise in transportation systems.Currently, moving objects database applications are being developed in an ad hoc fashion. Database Management System (DBMS) technology provides a potential foundation upon which to develop these applications, however, DBMS's are currently not used for this purpose. The reason is that there is a critical set of capabilities that are needed by moving objects database applications and are lacking in existing DBMS's. The objective of our Databases fOr MovINg Objects (DOMINO) project is to build an envelope containing these capabilities on top of existing DBMS's. In this paper we describe the problems and our proposed solutions.

In guinea pigs, the hyperopia present at birth rapidly reduces to emmetropia within the first 3 weeks of age. The emmetropization process in guinea pigs is mainly related to the increase in the vitreous chamber length. This relationship in guinea pigs is similar to that in chickens, tree shrews, primates and humans. The axial development of the vitreous chamber in guinea pigs appears to be associated with tissue growth of the posterior sclera.

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In C57BL/6 mouse eyes, myopia developed early and then the refractive error increased rapidly in the hyperopic direction to reach a peak at around 47 days with the major contributing changes being in axial length and corneal curvature.

It was recently demonstrated that chromaticity could affect eye growth and refractive development in guinea pigs but it remained unclear whether correction with spectacle lenses could balance these effects and how retinal responses change with different spectral compositions of light. Three illumination conditions were tested: blue, red and white light. Animals were raised without or with monocular spectacle lenses from three to seven weeks of age. Luminance electroretinograms (ERGs) were recorded to explore retinal responses with the different spectral compositions. In our special colony of pigmented guinea pigs, characterized by residual hyperopia, spontaneous myopia and poor emmetropization, red light induced early thinning of the choroid and relative myopia, compared to white light. Effects of red light could not be suppressed if positive spectacle lenses were worn. ERGs showed that red light failed to elicit robust retinal responses. Blue light inhibited axial eye growth, even when animals were reared with negative lenses. Intensity-matched blue and white light elicited similar a-waves but different b-waves, suggesting that the wavelength of light affects visual control of eye growth through different processing in the inner retina. We hypothesize that blue light might stimulate preferentially the ON pathway to inhibit myopia induced by negative lenses, at least in guinea pigs.

The human gut is a complex ecosystem occupied by a diverse microbial community. Modulation of this microbiota impacts health and disease. The definitive way to investigate the impact of dietary intervention on the gut microbiota is a human trial. However, human trials are expensive and can be difficult to control; thus, initial screening is desirable. Utilization of a range of in vitro and in vivo models means that useful information can be gathered prior to the necessity for human intervention. This review discusses the benefits and limitations of these approaches.

Segmented filamentous bacteria (SFB) are commensal organisms that grow by anchoring a specialized holdfast structure to the intestinal walls of a variety of animals. Interaction of SFB with Peyer’s patches in mice promotes the post-natal maturation of the immune system. We previously reported that the colonization of SFB in humans mainly occurs by 36 months of age, and is difficult to be detected afterward. In this study, we measured the level of SFB in intestinal fluids of human children. SFB were found via qPCR to represent a small fraction of the whole SFB-positive microbiota (105 SFB in 1011 total bacteria). Bacteria with filamentous segmented morphology were observed in intestinal fluids via fluorescent in situ hybridization, and from gut biopsies via scanning electron microscopy. SFB-specific DNA and peptide fragments were also identified via multiple displacement amplification PCR and mass spectrometry. There was an overall positive correlation between the presence of SFB and the titer of total secretory immunoglobulin A (sIgA), which is more apparent in intestinal fluids of the age group of 8–36 months. Afterward there was a decline of SFB in numbers correlated with a reduction of total sIgA. RT-qPCR analysis of the terminal ileal biopsies revealed that the expression of Th17 pathway genes were induced in SFB-positive samples, while the markers of T and B cell receptor signaling pathways were also upregulated. Collectively, these data suggest that SFB is a rare member of microbiota, and may play an important role in the development of human gut immunity.

Consider a database that represents the location of moving objects, such as taxi-cabs typical query: retrieve the cabs that are currently within 1 mile of 33 Michigan Ave., Chicago, or objects in a battle-eld. Existing database management systems DBMS's are not well equipped to handle continuously changing data, such as the position of moving objects, since data is assumed t o b e c onstant unless it is explicitly modied.In this paper we address position-update policies and imprecision. Namely, assuming that the actual position of a moving object m deviates from the position computed by the DBMS, when should m update its position in the database in order to eliminate the deviation? Furthermore, how can the DBMS provide a bound on the error i.e. the deviation when it replies to a query: what is the current position of m? We propose a cost based approach to update policies that answers both questions. We develop several update policies and analyze them theoretically and experimentally.