Eimeria spp. are a highly successful group of intracellular protozoan parasites that develop within intestinal epithelial cells of poultry, causing coccidiosis. As a result of resistance against anticoccidial drugs and the expense of manufacturing live vaccines, it is necessary to understand the relationship between Eimeria and its host more deeply, with a view to developing recombinant vaccine...

Type IV secretion systems (T4SS) are multiprotein structures that direct the translocation of specific molecules across the bacterial cell envelope. As in other bacteria, pathogenicity of the genus Brucella essentially depends on the integrity of the T4SS-encoding virB operon, whose expression is regulated by multiple transcription factors belonging to different families. Previously, we identif...

One of the most lasting contributions of Marr's posthumous book is his articulation of the different "levels of analysis" that are needed to understand vision. Although a variety of work has examined how these different levels are related, there is comparatively little examination of the assumptions on which his proposed levels rest, or the plausibility of the approach Marr articulated given th...

The intrinsic antimicrobial resistance of the opportunistic human pathogen Pseudomonas aeruginosa is compounded in mutant strains that overexpress multidrug efflux pumps such as the prominent drug-proton antiporter, MexAB-OprM. The primary regulator of the mexAB-oprM operon is the MarR family repressor, MexR. An additional repressor, NalC, also regulates mexAB-oprM by controlling expression of ...

Loess shoulder-lines are significant structural lines which divide the complicated loess landform into loess interfluves and gully-slope lands. Existing extraction algorithms for shoulder-lines mainly are based on local maximum of terrain features. These algorithms are sensitive to noise for complicated loess surface and the extraction parameters are difficult to be determined, making the extra...

non-real) objects: Plane geometric forms, solid geometric forms, and projected forms. The first class is the “real" class consisting of objects from the real world. The second class are representations of real objects. The third class are abstractions that can be represented using symbols but do not correspond to real objects (because they have no corresponding stimulus in the real world). Marr...

introduction: cleft lips and cleft palates are common congenital abnormalities in children. various chromosomal loci have been suggested to be responsible the development of these abnormalities. the present study was carried out to investigate the association between the suspected genes (methylenetetrahydrofolate reductase [mthfr] a1298c and c677t) that might contribute into the etiology of the...

Computation of the derivatives of an image defined on a lattice structure is of paramount importance in computer vision. The solution implies least square fitting of a continuous function to a neighborhood centered on the site where the value of the derivative is sought. We present a systematic approach to the problem involving orthonormal bases spanning the vector space defhred over the neighb...

An unsupervised method for detecting smooth contours in digital images is proposed. Following the a contrario approach, the starting point is defining the conditions where contours should not be detected: soft gradient regions contaminated by noise. To achieve this, low frequencies are removed from the input image. Then, contours are validated as the frontiers separating two adjacent regions, o...

OBJECTIVES To characterize the emrRCABsm operon of Stenotrophomonas maltophilia. METHODS The presence of the emrRCABsm operon was verified by RT-PCR. The regulatory role of EmrRsm was investigated by ΔemrRsm mutant construction and promoter transcriptional fusion assay. A susceptibility test was employed to assess the substrate spectrum of the EmrCABsm efflux pump. The requirement for each co...