Some features of coagulase positive staphylococci from bovine milk. II. Comparison of conventional techniques and the API Staph system

A total of 150 isolates of Staphylococcus aureus were subjected to the tests on the API Staph system. Of these, 50 were also tested by conventional methods, using the same tests as those found on the API Staph strips. Applying the principles of numerical taxonomy, the relationship between these isolates was 82% and more. Tests for the metabolism of sucrose and N-acetyl-glucosamine and for the production of argenine dihydrolysate and urease appear to be superfluous in the identification of S. aureus in this system.     

Effects of supplementing pregnant heifers with methionine or melatonin on the anatomy and other characteristics of their lateral hind claws

Three groups of four primiparous Holstein-Friesian heifers were fed throughout pregnancy either a control diet or that diet supplemented with either 5 to 6 g per day of rumen-protected intestinally available methionine or 25 mg melatonin. They were euthanased three days after calving. The dietary supplements had no effect on the impression hardness or the concentrations of cysteine and methionine in samples of claw horn collected from a range of sites, or on the areas of erosion in the sole and heel. Significant differences were recorded for the hardness of the horn in the order wall >sole >heel. These differences were associated with higher concentrations of cysteine and lower concentrations of methionine in samples of horn from the dorsal wall than in samples from the prebulbar region of the sole. There were no significant differences attributable to the dietary supplements in the soft tissue anatomy of the solear dermis and epidermis.     

Development and evaluation of a high-throughput,low-cost genotyping platform based on oligonucleotide microarrays in rice

Background  

We report the development of a microarray platform for rapid and cost-effective genetic mapping, and its evaluation using rice as a model. In contrast to methods employing whole-genome tiling microarrays for genotyping, our method is based on low-cost spotted microarray production, focusing only on known polymorphic features.     

The theropod ancestry of birds: new evidence from the late cretaceous of madagascar

A partial skeleton of a primitive bird, Rahona ostromi, gen. et sp. nov., has been discovered from the Late Cretaceous of Madagascar. This specimen, although exhibiting avian features such as a reversed hallux and ulnar papillae, retains characteristics that indicate a theropod ancestry, including a pubic foot and hyposphene-hypantra vertebral articulations. Rahona has a robust, hyperextendible second digit on the hind foot that terminates in a sicklelike claw, a unique characteristic of the theropod groups Troodontidae and Dromaeosauridae. A phylogenetic analysis places Rahona with Archaeopteryx, making Rahona one of the most primitive birds yet discovered.     

Detecting the undetectable: Characterization,optimization, and validation of an eDNA detection assay for the federally endangered dwarf wedgemussel,Alasmidonta heterodon (Bivalvia: Unionoida)

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Human-altered and human-transported (HAHT) soils in the U.S. soil classification system

ABSTRACT

Human-altered and human-transported (HAHT) soils are widespread across the globe and are concentrated near where people live and work. Although some of the HAHT soils are significant because they can be hazardous to human, animal, and plant health, most are not mapped or classified to the same extent as agricultural soils. The purpose of this article is to discuss the occurrence, types, and importance of HAHT soils and to document the historical and proposed classification of HAHT soils in Soil Taxonomy. There are two main forms of materials that define HAHT soils: human-altered soils formed in human-altered materials (HAM) from the soil surface to 50 cm (or to bedrock if shallower) or more and human-transported soils formed in human-transported materials (HTM) from the soil surface to 50 cm (or to bedrock if shallower) or more. The HAHT soils mainly occur in urban areas, transportation corridors, mined lands, landfills, filled shallow water, and agricultural areas on anthropogenic landforms. Hazards include danger from radioactivity, pollution, content of hazardous artifacts, or presence on unstable landforms that may fail during heavy rains or earthquakes. The HAHT soils are extensive, and their extent is growing. In the past, few HAHT soils were described or classified adequately because the U.S. Soil Taxonomy system was established for agricultural and other naturally occurring soils. However, HAHT soils are now being recognized and classified in many soil classification systems at very high levels. A new soil order is proposed for U.S. Soil Taxonomy that would include the most obvious profoundly and intentionally altered HAHT soils. A discussion and justification is given for an unofficial proposal. Input will be collected from international groups of scientists, and modifications of the unofficial proposal are expected. The long-term result of establishing a new soil order will be to enable proper classification, allocation, and mapping of HAHT soils worldwide.