Vertebral Pneumaticity in the Ornithomimosaur Archaeornithomimus (Dinosauria: Theropoda) Revealed by Computed Tomography Imaging and Reappraisal of Axial Pneumaticity in Ornithomimosauria

Among extant vertebrates, pneumatization of postcranial bones is unique to birds, with few known exceptions in other groups. Through reduction in bone mass, this feature is thought to benefit flight capacity in modern birds, but its prevalence in non-avian dinosaurs of variable sizes has generated competing hypotheses on the initial adaptive significance of postcranial pneumaticity. To better understand the evolutionary history of postcranial pneumaticity, studies have surveyed its distribution among non-avian dinosaurs. Nevertheless, the degree of pneumaticity in the basal coelurosaurian group Ornithomimosauria remains poorly known, despite their potential to greatly enhance our understanding of the early evolution of pneumatic bones along the lineage leading to birds. Historically, the identification of postcranial pneumaticity in non-avian dinosaurs has been based on examination of external morphology, and few studies thus far have focused on the internal architecture of pneumatic structures inside the bones. Here, we describe the vertebral pneumaticity of the ornithomimosaur Archaeornithomimus with the aid of X-ray computed tomography (CT) imaging. Complementary examination of external and internal osteology reveals (1) highly pneumatized cervical vertebrae with an elaborate configuration of interconnected chambers within the neural arch and the centrum; (2) anterior dorsal vertebrae with pneumatic chambers inside the neural arch; (3) apneumatic sacral vertebrae; and (4) a subset of proximal caudal vertebrae with limited pneumatic invasion into the neural arch. Comparisons with other theropod dinosaurs suggest that ornithomimosaurs primitively exhibited a plesiomorphic theropod condition for axial pneumaticity that was extended among later taxa, such as Archaeornithomimus and large bodied Deinocheirus. This finding corroborates the notion that evolutionary increases in vertebral pneumaticity occurred in parallel among independent lineages of bird-line archosaurs. Beyond providing a comprehensive view of vertebral pneumaticity in a non-avian coelurosaur, this study demonstrates the utility and need of CT imaging for further clarifying the early evolutionary history of postcranial pneumaticity

Dynamics of soyabean production in Nigerian agriculture

Despite large oil reserve, Nigeria as a developing country has urgent economic problems which only agriculture can alleviate. The introduction of soyabean in Nigerian agricultural system can diversify the food for both man and his livestock. Soyabean is a crop with high potentials, but its future in the agricultural system may depend on its performance as a component of polyculture and acceptability in the traditional cropping systems. Soyabean has desirable characteristics for intercropping such as erect growth habit, and high productivity under wide row spacing, nevertheless, soyabean is currently rarely used in intercrop combinations. Successful introduction of soyabean into intercrop system will ensure greater diversification of crops grown within each agroecological region of the country. The general adoption of the crop has been very limited despite some notable success in some specific areas like expansion and utilization. Soyabean production problems are mostly critical during establishment, maturity and storage. Keywords: agricultural system, cropping system, sustainable agriculture, Glycine max, productivity, soyabean adoptionGlobal Journal of Agricultural Sciences Vol. 4(2) 2005: 169-17

Ein garantiertes Einkommen oder eine garantierte Arbeit?

PURPOSE. Leber congenital amaurosis (LCA) is genetically heterogeneous, with 15 genes identified thus far, accounting for similar to 70% of LCA patients. The aim of the present study was to identify new genetic causes of LCA. METHODS. Homozygosity mapping in > 150 LCA patients of worldwide origin was performed with high-density SNP microarrays to identify new disease-causing genes. RESULTS. In three isolated LCA patients, the authors identified large homozygous regions on chromosome 3 encompassing the IQCB1 gene, which has been associated with Senior-Loken syndrome (SLSN), characterized by nephronophthisis and retinal degeneration. Mutation analysis of IQCB1 in these three patients and a subsequent cohort of 222 additional LCA patients identified frameshift and nonsense mutations in 11 patients diagnosed with LCA. On re-inspection of the patient's disease status, seven were found to have developed SLSN, but four maintained the diagnosis of LCA as the kidney function remained normal. CONCLUSIONS. Results show that the onset of renal failure in patients with IQCB1 mutations is highly variable, and that mutations are also found in LCA patients without nephronophthisis, rendering IQCB1 a new gene for LCA. However, these patients are at high risk for developing renal failure, which in early stages is often not recognized and can cause sudden death from fluid and electrolyte imbalance. It is therefore recommended that all LCA patients be screened for IQCB1 mutations, to follow them more closely for kidney disease. (Invest Ophthalmol Vis Sci. 2011;52:834-839) DOI:10.1167/iovs.10-522