Use of Portable Piloting Units by Maritime Pilots

The use of electronic navigation equipment onboard maritime vessels continues to increase, worldwide. The results of a recent Canadian study provide clear evidence that maritime pilots know what types of equipment to use -- and how to use them

Metrics and spectral triples for Dirichlet and resistance forms

The article deals with intrinsic metrics, Dirac operators and spectral triples induced by regular Dirichlet and resistance forms. We show, in particular, that if a local resistance form is given and the space is compact in resistance metric, then the intrinsic metric yields a geodesic space. Given a regular Dirichlet form, we consider Dirac operators within the framework of differential 1-forms proposed by Cipriani and Sauvageot, and comment on its spectral properties. If the Dirichlet form admits a carr\'e operator and the generator has discrete spectrum, then we can construct a related spectral triple, and in the compact and strongly local case the associated Connes distance coincides with the intrinsic metric. We finally give a description of the intrinsic metric in terms of vector fields

Inaccurate age and sex data in the Census PUMS files: evidence and implications

We discover and document errors in public use microdata samples ("PUMS files") of the 2000 Census, the 2003-2006 American Community Survey, and the 2004-2009 Current Population Survey. For women and men ages 65 and older, age- and sex-specific population estimates generated from the PUMS files differ by as much as 15% from counts in published data tables. Moreover, an analysis of labor force participation and marriage rates suggests the PUMS samples are not representative of the population at individual ages for those ages 65 and over. PUMS files substantially underestimate labor force participation of those near retirement ages and overestimate labor force participation rates of those at older ages. These problems were an unintentional by-product of the misapplication of a newer generation of disclosure avoidance procedures carried out on the data. The resulting errors in the public use data could significantly impact studies of people ages 65 and older, particularly analyses of variables that are expected to change by age.Census ; Population ; Labor supply

The short-lived MATα2 transcriptional regulator is ubiquitinated in vivo

The substrates of ubiquitin-dependent proteolytic pathways include both damaged or otherwise abnormal proteins and undamaged proteins that are naturally short-lived. Few specific examples of the latter class have been identified, however. Previous work has shown that the cell type-specific MAT-alpha-2 repressor of the yeast Saccharomyces cerevisiae is an extremely short-lived protein. We now demonstrate that alpha-2 is conjugated to ubiquitin in vivo. More than one lysine residue of alpha-2 can be joined to ubiquitin, and some of the ubiquitin moieties form a Lys48-linked multiubiquitin chain. Overexpression of degradation-impaired ubiquitin variants was used to show that at least a significant fraction of alpha-2 degradation is dependent on its ubiquitination