We report the fabrication of the first extruded hollow core optical fiber with a single ring of cladding holes, and its use in a chemical sensing application. These single suspended ring structures ...show antiresonance reflection optical waveguiding (ARROW) features in the visible part of the spectrum. The impact of preform pressurization on the geometry of these fibers is determined by the size of the different hole types in the preform. The fibers are used to perform Raman sensing of methanol, demonstrating their potential for future fiber sensing applications.
The Coquí Call Spooner, T. M.
Latin American literary review,
10/2023, Letnik:
50, Številka:
101
Journal Article
Recenzirano
Odprti dostop
T. M. Spooner is the author of the novels The Salvation of La Purísima and Notes from Exile. Among others, his short fiction can be found in The Almagre Review and Flying Island Journal as the ...recipient of the 2022 Short Fiction prize. His essays have appeared in Studies in American Naturalism and Hispanic Journal. Spooner earned an M.A. in English Literature from Northern Arizona University.
More than 85 percent of Australian terrestrial genera with a body mass exceeding 44 kilograms became extinct in the Late Pleistocene. Although most were marsupials, the list includes the large, ...flightless mihirung Genyornis newtoni. More than 700 dates on Genyornis eggshells from three different climate regions document the continuous presence of Genyornis from more than 100,000 years ago until their sudden disappearance 50,000 years ago, about the same time that humans arrived in Australia. Simultaneous extinction of Genyornis at all sites during an interval of modest climate change implies that human impact, not climate, was responsible.
The greatest diversity of stingless bee species is found in warm tropical regions, where brood thermoregulation is unnecessary for survival. Although
Austroplebeia australis
(Friese) naturally occurs ...in northern regions of Australia, some populations experience extreme temperature ranges, including sub-zero temperatures. In this study, the temperature was monitored in
A. australis
colonies’ brood chamber (
n
= 6) and the hive cavity (
n
= 3), over a 12-month period. The
A. australis
colonies demonstrated some degree of thermoconformity, i.e. brood temperature although higher correlated with cavity temperature, and were able to warm the brood chamber throughout the year. Brood production continued throughout the cold season and developing offspring survived and emerged, even after exposure to very low (−0.4 °C) and high (37.6 °C) temperatures.
Austroplebeia australis
, thus, demonstrated a remarkable ability to survive temperature extremes, which has not been seen in other stingless bee species.
Suspended sediment is a major water quality problem, yet few monitoring studies have been of sufficient scale and duration to assess the effectiveness of land-use change or conservation practice ...implementation at a watershed scale. Daily discharge and suspended sediment export from two 5,000-ha watersheds in central Iowa were monitored over a 10-year period (water years 1996-2005). In Walnut Creek watershed, a large portion of land was converted from row crop to native prairie, whereas in Squaw Creek land use remained predominantly row crop agriculture. Suspended sediment loads were similar in both watersheds, exhibiting flashy behavior typical of incised channels. Modeling suggested that expected total soil erosion in Walnut Creek should have been reduced 46% relative to Squaw Creek due to changes in land use, yet measured suspended sediment loads showed no significant differences. Stream mapping indicated that Walnut Creek had three times more eroding streambank lengths than did Squaw Creek suggesting that streambank erosion dominated sediment sources in Walnut Creek and sheet and rill sources dominated sediment sources in Squaw Creek. Our results demonstrate that an accounting of all sources of sediment erosion and delivery is needed to characterize sediment reductions in watershed projects combined with long-term, intensive monitoring and modeling to account for possible lag times in the manifestation of the benefits of conservation practices on water quality. PUBLICATION ABSTRACT
Optically stimulated luminescence has been demonstrated within a fluoride phosphate glass optical fibre. These fibres have been used as the basis of a novel dosimeter architecture whereby the optical ...fibre acts as both the sensing and light guiding component. Fibres were fabricated from a commercially acquired glass and irradiated using a super(90)Sr/ super(90)Y source. Following optical stimulation with a 532 nm laser, optically stimulated luminescence of 483 plus or minus 18 cnts/g/ mu J was detected. In addition to OSL, scintillation of 6155 plus or minus 78 cnts/s was also measured. A linear response between 0.16 - 2 Gy of irradiation was measured, after which the intensity was observed to plateau. These results indicate the potential suitability of fluoride phosphate optical fibres for radiation sensing applications.
The complete small subunit ribosomal RNA (srRNA) gene of Theileria parva was cloned and sequenced. Two primers were designed which permitted the specific amplification of part of the Theileria srRNA ...gene from Theileria-infected cell line samples which were predominantly (> 95%) bovine DNA. The sequence of the central (variable) region of the srRNA genes of T. annulata, T. taurotragi, T. mutants and two unidentified parasites referred to as Theileria sp. (buffalo) and Theileria sp. (Marula) were obtained. An alignment of the sequences was generated from which 6 oligonucleotide probes, corresponding to species-specific regions, were designed. These probes were demonstrated to provide unequivocal identification of each of the 6 species either by direct detection of parasite srRNA or by hybridization to amplified parasite srRNA genes. The probes were not able to distinguish buffalo-derived T. parva, the causal agent of Corridor disease, from cattle-derived T. parva, the causal agent of East Coast fever.
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