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Hartree–Fock (HF) calculations for a variety of single-walled carbon nanotube (SWCNT) systems indicate linear relationships between electronic energies and changes in length and circumference for both armchair and zigzag type nanotubes. A simple protocol to predict energies for large SWCNT (C atoms >500) is developed through a set of structural parameters and AM1 optimized geometries from small SWCNTs. The energetic trends shown by the calculations are used to support the theory of SWCNT nucleation from a preformed carbon, or graphene with six 5-member rings, cap. [ABSTRACT FROM AUTHOR]

A survey of external lesions on Atlantic tomcod from the St Lawrence River was carried out between mid-December 1992 and the end of January 1993 (n = 1674). Jaw ulcerations were observed in 3.8% of the fish. These ulcers were usually single, and located at the junction between the skin epidermis and oral mucosa. They progressed from shallow lesions to deep ulcers with pathological fracture of the facial bone secondary to osteitis. The aetiology of these lesions could not be determined. Fish with ulcers were generally older than those of the monitored spawning population. The reason for a higher prevalence in older tomcods is unknown, but decreased immune functions and healing capacity caused by ageing are suggested as potential predisposing factors. [ABSTRACT FROM AUTHOR]

The article presents a study on the safety and efficiency of emamectin benzoate for the treatment of Anguillicoloides crassus infections in American eels. The study used 54 eels which were randomly divided into one group of 24 eels and two groups of 15 eels each to receive varying treatments of emamectin benzoate. Results show that single administration of the chemical is safe for the subjects and is enough to kill A. crassus in the infected eels' swim bladder.

Philometra rubra (Leidy, 1856) is a pathogenic parasitic nematode infecting striped bass ( Morone saxatilis (Walbaum, 1792)) in eastern North America. Identification of philometrids is difficult, male P. rubra have never been found, and transmission is poorly understood. To re-establish the 'Extirpated' striped bass population in the St. Lawrence Estuary (SLE), Quebec, young-of-the-year (YOY) striped bass from the Miramichi River, New Brunswick, were collected and released into the SLE. The present study was undertaken to find Philometra in striped bass from the Miramichi River, for identification, description, and examine transmission and lesions. Philometra rubra was identified in 100% of 32 YOY (intensity = 26-125) and 100% of nine 1-year-old (intensity = 4-25 in five striped bass) striped bass collected in summer 2011. The swim bladder and body cavity were sites of infection in YOY with no tissue response observed histopathologically. Gravid P. rubra females occurred in the body cavity and swim bladder, with males predominately in the latter site. Males were short-lived, being absent in 1-year-old bass. Adult male and adult female P. rubra are described. Males of P. rubra can be distinguished from other described species based on spicule, gubernaculum, and body-length measurements. This parasite may have implications for the re-introduction program and conservation of striped bass in the SLE and in other populations. [ABSTRACT FROM AUTHOR]

The striped bass, Morone saxatilis (Walbaum), once represented an important resource for fisheries in the St Lawrence River (Quebec, Canada). A restoration programme, involving captive propagation, was implemented with the objective of restocking the population, which had disappeared in the late 1960s. An unusually high rate of mortality was observed during the winter of 2006 in captive-raised fingerlings that were originally collected from the Miramichi River (New Brunswick, Canada) the previous summer. Post-mortem examinations revealed extensive granulomatous and hyperplastic peritonitis associated with numerous nematodes of the genus Philometra. Given the severity of the lesions, high intensity of infection by Philometra sp. was presumed to be the primary factor in the unusual mortalities reported that winter. Observations suggest that this nematode, which was acquired in the wild, cannot establish itself in a captive environment, most likely because of the absence of the obligate intermediate host. Examination of archived specimens of striped bass showed that this parasite was probably present in the St Lawrence River population prior to its extirpation. Consequently, the introduction of infected fish into this ecosystem should not be a concern. Nevertheless, infection-related mortalities of fingerlings might affect dynamics of wild striped bass populations. [ABSTRACT FROM AUTHOR]

In recent years, an increasing number of projects have investigated tumor genome structure, using microarray-based techniques like array comparative genomic hybridization (array-CGH) or single nucleotide polymorphism (SNP) arrays. The forthcoming studies have to integrate these former results and compare their findings to the existing sets of copy number data for validation. These sets also form the basis from which many comparative retrospective analyses can be carried out. Nevertheless, exploitation of this mass of data relies on a homogeneous preparation of copy number data, which will make it possible to compare them together, and their integration into a unified bioinformatics environment with ad hoc analysis tools and interfaces. To our knowledge, no such data integration has been proposed yet. Therefore the biologists and clinicians involved in cancer research urgently need such an integrative tool, which motivated us to undertake the construction of a database for array-CGH and other DNA copy number data for tumors (ACTuDB). When available, the associated clinical, transcriptome and loss of heterozygosity data were also integrated into ACTuDB. ACTuDB contains currently about 1500 genomic profiles for tumors and cell lines for the bladder, brain, breast, colon, liver, lymphoma, neuroblastoma, mouth and pancreas, together with data for replication timing experiments. The CGH array data were processed, using ad hoc algorithms (probe mapping, breakpoint detection, gain or loss status assignment and visualization) developed at Institut Curie. The database is available from http://bioinfo.curie.fr/actudb/ and can be browsed with a user-friendly interface. This database will be a useful resource for the genomic profiling of tumors, a field of highly active research. We invite research groups involved in tumor genome profiling to submit their data to ACTuDB.Oncogene (2007) 26, 6641–6652; doi:10.1038/sj.onc.1210488; published online 14 May 2007 [ABSTRACT FROM AUTHOR]

The development and fabrication of α-brass pans, including the sinking of the pan head in the traditional manner using a hammer and patterning musical notes and their turning is compared with a low-carbon steel (Caribbean-type) pan as a standard. In this study these experimental pans are fabricated by welding the α-brass or low-carbon steel platforms to a low-carbon steel hoop and side metal or skirt. These pans are 2.54 cm larger in diameter than pans traditionally fabricated from 55-gallon barrels. The corresponding pan head materials are examined by optical and electron microscopy and hardness profiles are measured as well. Deformation is shown to influence the acoustic response of ideal, flat circular discs of both the α-brass and low-carbon steel as well as 316L stainless steel. The frequency-amplitude-time spectra for common octave ranges are compared and chromatic tones are shown for the α-brass as well as the low-carbon steel standard. These results indicate that a wide range of hard metals or alloys can be used to produce musical pan instruments. [ABSTRACT FROM AUTHOR]