Measures of Neural Similarity.

One fundamental question is what makes two brain states similar. For example, what makes the activity in visual cortex elicited from viewing a robin similar to a sparrow? One common assumption in fMRI analysis is that neural similarity is described by Pearson correlation. However, there are a host of other possibilities, including Minkowski and Mahalanobis measures, with each differing in its mathematical, theoretical, and neural computational assumptions. Moreover, the operable measures may vary across brain regions and tasks. Here, we evaluated which of several competing similarity measures best captured neural similarity. Our technique uses a decoding approach to assess the information present in a brain region, and the similarity measures that best correspond to the classifier's confusion matrix are preferred. Across two published fMRI datasets, we found the preferred neural similarity measures were common across brain regions but differed across tasks. Moreover, Pearson correlation was consistently surpassed by alternatives.

Streptococcal infection in dogs: a retrospective study of 393 cases.

Streptococcus spp are opportunistic pathogens that normally reside in the upper respiratory, intestinal, lower urinary, and genital tracts but can cause localized infection or septicemia in dogs of all ages. A retrospective study of streptococcal infection in 393 dogs was conducted to identify the species of Streptococcus isolated, determine demographics of affected dogs, and characterize the disease processes associated with infection. The major streptococcal species isolated were S canis (88 cases, 22.4%), S dysgalactiae ssp equisimilis (13, 3.3%), and S equi ssp zooepidemicus (4, 1.0%). Sex was not a risk factor (P > .30). Fetuses and neonates were more likely to have streptococcal infection than were other age groups (P < .001). Streptococcal septicemia was considered an important cause of abortion and neonatal death and was isolated from all samples submitted for aerobic culture from dogs in that age group. There was a seasonal trend, with dogs more likely to have streptococcal infection in summer months. In dogs for which a disease process was identified, streptococcal infection was associated with dermatitis (29 dogs), pneumonia (24 dogs), adult septicemia (13 dogs), and fetal/neonatal septicemia leading to abortion or neonatal death (16 dogs). Identification of other clinically significant bacterial, viral, fungal, and parasitic organisms was common (267 of 393 dogs, 68%), especially in dogs with dermatitis or pneumonia. Infection with Streptococcus spp should be considered in the differential diagnosis in cases of abortion, septicemia, dermatitis, and pneumonia in dogs. Clinical significance of isolation of streptococcal organisms should be interpreted in context of clinical signs and pathologic findings.

Real-time multiplex PCR assay for rapid detection and toxintyping of Clostridium perfringens toxin producing strains in feces of dairy cattle.

Clostridium perfringens is an anaerobic, gram-positive, spore-forming bacterium associated with a wide variety of diseases in domestic animals and humans. We have developed dual-labeled fluorescence hybridization probe (TaqMan((R)))-based real-time multiplex PCR assay for detection of toxin genes alpha (cpa), beta (cpb), iota (ia), epsilon (etx), beta2 (cpb2) and enterotoxin (cpe) of C. perfringens directly from cattle feces. The assay was standardized using ATCC reference strains of C. perfringens producing alpha, beta, iota, epsilon and enterotoxin, respectively. The assay for detection of beta2 toxin gene was standardized using a field strain of C. perfringens producing beta2 toxin. The minimum detection limit for the real time PCR assay ranged from 5 to 70 pg of DNA for the six toxin genes. A total of 307 fecal samples collected from seven dairy herds in Pennsylvania were analyzed using the multiplex assay. The real-time PCR assay revealed that cpa, cpb, ia, etx, cpb2 and cpe were detected in 68 (28.2%), 6 (2.5%), 6 (2.5%), 4 (1.6%), 164 (68%) and 11 (4.5%) of 241 PCR positive samples, respectively. The findings of the study revealed that C. perfringens beta2 toxin producing strains were widely prevalent in lactating cows in Pennsylvania and they may play an important role in C. perfringens associated diarrheal diseases.

Antimicrobial susceptibility of mastitis pathogens from first lactation and older cows.

Increasing antimicrobial resistance has become a serious concern worldwide and antimicrobial use in animal agriculture is currently under scrutiny. Mastitis is the most common reason for antibiotic use in dairy herds and thus, antimicrobial resistance of mastitis pathogens has received recent attention. The purpose of this study was to describe and compare antimicrobial susceptibility of mastitis pathogens isolated at calving from first lactation and older cows. A total of 202 bacteria were isolated from intramammary infections (IMIs) within 3 days after calving over a 16-month study period in the Krauss Dairy Research Herd at the Ohio Agricultural Research and Development Center (OARDC) in Wooster, OH. Of these IMIs, 78% were caused by coagulase-negative staphylococci (CNS). Forty-four percent of them were resistant to at least one antibiotic. Most resistance was observed against penicillin, 39% of the isolates from older cows and 26% from first lactation cows being resistant to penicillin (P > 0.05). Also MIC90 for penicillin was higher among isolates from older cows. On the other hand, resistance to tetracycline was more common and MIC90 higher among isolates from first lactation cows than from older cows. Differences in the proportions of resistant isolates between first lactation and older cows were not statistically significant, though. The resistance patterns of the CNS isolated during the study are concordant with antimicrobial usage in the study herd. This is in agreement with the generally accepted notion that selection pressure from the use of antibiotics is a main factor in development of antibiotic resistance.

A structural account of global and local processing.

The order of processing, whether global forms are processed prior to local forms or vice versa, has been of considerable interest. Many current theories hold that the more perceptually conspicuous form is identified first. An alternative view is presented here in which the stuctural relations among elements are an important factor in explaining the relative speeds of global and local processing. We equated the conspicuity of the global and local forms in three experiments and still found advantages in the processing of global forms. Subjects were able to process the relations among the elements quickly, even before the elements themselves were identified. According to our alternative view, subjects created equivalence classes of similar and proximate local elements before identifying the constituent elements. The experiments required subjects to decide whether two displays were the same or different, and consequently, the results are relevant to work in higher-level cognition that stresses the importance of comparison processes (e.g., analogy and conceptual combination). We conclude by evaluating related work in higher-level cognition in light of our findings.

Cloning and sequence of the groESL heat-shock operon of Pasteurella multocida.

By using degenerate oligodeoxyribonucleotide primers for conserved regions of groEL, a 0.6-kb fragment of Pasteurella multocida genomic DNA was amplified using PCR. The amplified fragment was then used as a probe to isolate a genomic fragment containing the entire GroESL operon. The isolated genomic fragment was found to contain two open reading frames, the sequences of which were highly homologous to the prokaryotic groES and groEL families of genes.

Pasteurella multocida produces heat shock proteins in turkeys.

Pasteurella multocida produces an acute septicemic disease of turkeys. Since turkeys have a normal body temperature of 42 degrees C, it follows that P. multocida would produce heat shock proteins during the course of the infectious process. We show here that P. multocida produces several proteins at 42 degrees C, but not at 32 degrees C, and vice versa. Four of these proteins (70, 60, 40, and 35 kDa in molecular mass) were recognized by serum obtained from a turkey infected with P. multocida, suggesting that they were produced in vivo.