A Comparison of Feature Density for Large Scale Online Maps

Large scale maps as provided by Google, Microsoft Bing, and Mapbox among others provide users an important source of information for local environments. Comparing maps from these services helps to evaluate both the quality of the underlying spatial data and the rendering process. A comparison procedure is used that generates large scale map pairs at random locations using the Application Programmer Interface (API) for three different mapping services. The quality of each representation is then evaluated for feature and label density. The comparison is done for three different continents. For North America, it was found that maps from Google had consistently higher feature and label density than those from Microsoft Bing and Mapbox. Google Maps also held an advantage in Europe. Maps from Microsoft Bing were more detailed in Sub-Saharan Africa in comparison to both Google Maps and Mapbox. Maps from Mapbox, that relies exclusively on data from OpenStreetMap, had the lowest feature and label density for all three areas.

A Correction Method of a Binary Classifier Applied to Multi-Label Pairwise Models

In the paper, the problem of multi-label (ML) classification using the label-pairwise (LPW) scheme is addressed. For this approach, the method of correction of binary classifiers which constitute the LPW ensemble is proposed. The correction is based on a probabilistic (randomized) model of a classifier that assesses the local class-specific probabilities of correct classification and misclassification. These probabilities are determined using the original concepts of a randomized reference classifier (RRC) and a local soft confusion matrix. Additionally, two special cases that deal with imbalanced labels and double labeled instances are considered. The proposed methods were evaluated using 29 benchmark datasets. In order to assess the efficiency of the introduced models and the proposed correction scheme, they were compared against original binary classifiers working in the LPW ensemble. The comparison was performed using four different ML evaluation measures: macro and micro-averaged [Formula: see text] loss, zero-one loss and Hamming loss. Moreover, relations between classification quality and the characteristics of ML datasets such as average imbalance ratio or label density were investigated. The experimental study reveals that the correction approaches significantly outperform the reference method in terms of zero-one loss and Hamming loss.

Dietary Cl− restriction upregulates pendrin expression within the apical plasma membrane of type B intercalated cells

Pendrin, encoded by Slc26a4, is a Cl−/HCO3− exchanger expressed in the apical region of type B and non-A, non-B intercalated cells, which regulates renal NaCl excretion. Dietary Cl− restriction upregulates total pendrin protein expression. Whether the subcellular expression of pendrin and whether the apparent vascular volume contraction observed in Slc26a4 null mice are Cl− dependent, but Na+ independent, is unknown. Thus the subcellular distribution of pendrin and its role in acid-base and fluid balance were explored using immunogold cytochemistry and balance studies of mice ingesting a NaCl-replete or a Na+-replete, Cl−-restricted diet, achieved through substitution of NaCl with NaHCO3. Boundary length and apical plasma membrane pendrin label density each increased by ∼60–70% in type B intercalated cells, but not in non-A, non-B cells, whereas cytoplasmic pendrin immunolabel increased ∼60% in non-A, non-B intercalated cells, but not in type B cells. Following either NaCl restriction or Cl− restriction alone, Slc26a4 null mice excreted more Cl− and had a higher arterial pH than pair-fed wild-type mice. In conclusion, 1) following dietary Cl− restriction, apical plasma membrane pendrin immunolabel increases in type B intercalated cells, but not in non-A, non-B intercalated cells; and 2) pendrin participates in the regulation of renal Cl− excretion and arterial pH during dietary Cl− restriction.

The spleen modulates the febrile response of guinea pigs to LPS

The febrile responses of splenectomized (Splex) or sham-operated (Sham) guinea pigs challenged intravenously or intraperitoneally with lipopolysaccharide (LPS) 7 and 30 days after surgery were evaluated. FITC-LPS uptake by Kupffer cells (KC) was additionally assessed 15, 30, and 60 min after injection. LPS at 0.05 μg/kg iv did not evoke fever in Sham animals but caused a 1.2°C core temperature (Tc) rise in the Splex animals. LPS at 2 μg/kg iv induced a 1.8°C greater Tcrise of the Splex animals than of their controls. LPS at 2 and 8 μg/kg ip 7 days postsurgery induced 1.4 and 1.8°C higher fevers, respectively, in the Splex than Sham animals. LPS at 2 and 8 μg/kg ip 30 days postsurgery also increased the febrile responses of the asplenic animals by 1.6 and 1.8°C, respectively. FITC-LPS at 7 days was detected in the controls within KC 15 min after its administration; the label density was reduced at 30 min and almost 0 at 60 min. In the Splex group, in contrast, the labeling was significantly denser and remained unchanged through all three time points; this effect was still present 30 days after surgery. Similar results were obtained at 60 min after FITC-LPS intraperitoneal injection. Gadolinium chloride pretreatment (−3 days) of the Splex group significantly reduced both their febrile responses to LPS (8 μg/kg ip) and their KC uptake of FITC-LPS 7 days postsurgery. Thus splenectomy increases the magnitude of the febrile response of guinea pigs and the uptake of systemically administered LPS.

Characterization and immunolocalization of a main proteinaceous component of the cell wall of the protozoan parasite Perkinsus atlanticus

Described in the present study is a major component of the cell wall of 2 of the most pathogenic parasites of molluscs, Perkinsus atlanticus and P. marinus. The component is a high molecular weight protein (233 kDa), which we have named PWP-1 (for Perkinsus wall protein-1). Western blots, using a polyclonal serum generated against purified PWP-1 from P. atlanticus, revealed that this protein is expressed by all walled developmental stages of this protozoon. By means of immunogold electron microscopy, labelling for PWP-1 was strong and specifically associated with the cell wall. The label density and distribution pattern was quite different between trophozoites and prezoosporangia. With regard to the structural organization of this protein, PWP-1 is disulphide-linked to other cell wall components and released from the cell wall only following treatment with a sulphydryl agent. We also report that PWP-1 is a trypsin-resistant protein, both in its native and heat-denatured conformation. In addition, results from the N-terminal microsequence of this protein allow us to define PWP-1 as a novel cell wall protein. Overall, our findings strongly suggest that PWP-1 plays a key role in the organization of the cell wall of these protozoa, promoting their survival.