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41.
The free modulation of interlayer distance in a layered high-transition temperature (high-Tc) superconductor is of crucial importance not only for the study of the superconducting mechanism but also for the practical application of high-Tc superconducting materials. Two-dimensional (2D) superconductors were achieved by intercalating a long-chain organic compound into bismuth-based high-Tc cuprates. Although the intercalation of the organic chain increased the interlayer distance remarkably, to tens of angstroms, the superconducting transition temperature of the intercalate was nearly the same as that of the pristine material, suggesting the 2D nature of the high-Tc superconductivity. 相似文献
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The equine industries in Ireland are vibrant and growing. They are broadly classified into two sectors: Thoroughbred racing, and sports and leisure. This paper describes these sectors in terms of governance, education and training in equine welfare, and available data concerning horse numbers, identification, traceability and disposal. Animal welfare, and specifically equine welfare, has received increasing attention internationally. There is general acceptance of concepts such as animal needs and persons' responsibilities toward animals in their care, as expressed in the 'Five Freedoms'. As yet, little has been published on standards of equine welfare pertaining to Ireland, or on measures to address welfare issues here. This paper highlights the central role of horse identification and legal registration of ownership to safeguard the health and welfare of horses. 相似文献
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Connolly Dj Dwyer P Fagan J Hayes M Ryan E Costello E Kilroy A More S 《Irish veterinary journal》2008,61(8):533-537
Tuberculosis (TB), due to infection with Mycobacterium bovis was diagnosed in a flock of alpaca in Ireland in 2004. An epidemiological investigation was conducted to identify the risk of TB for farmed alpaca where TB is endemic, the origin of the infection, the potential for alpaca-to-alpaca transmission and appropriate control measures. The investigation focused on the alpaca flock (including the farm, animal movements and breeding, feeding and flock health practice), the disease episode (including animal disease events and subsequent control measures) and TB infection risk in the locality. The TB risk to alpaca is high in areas where infection is endemic in cattle and badgers and where biosecurity is inadequate. It is most likely that the source of infection for the alpaca was a local strain of M. bovis, present in cattle in this area since at least 2001. Genotyping of isolates identified a single variable number tandem repeat (VNTR) profile in both cattle and alpaca in this region. Although a tuberculous badger was also removed from the vicinity, bacterial isolation was not attempted. On this farm, infection in alpaca was probably derived from a common source. Alpaca-to-alpaca transmission seems unlikely. Two broad control strategies were implemented, aimed at the rapid removal of infected (and potentially infectious) animals and the implementation of measures to limit transmission. Tests that proved useful in detecting potentially-infected animals included measurement of the albumin-to-globulin ratio and regular body condition scoring. Skin testing was time consuming and unproductive, and early detection of infected animals remains a challenge. The flock was managed as a series of separate groupings, based on perceived infection risk. No further TB cases have been detected. 相似文献
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Louise Katherine BARTOLAC Jenna Louise LOWE George KOUSTAS Cecilia SJ?BLOM Christopher Gerald GRUPEN 《The Journal of reproduction and development》2015,61(6):525-531
The aim of this study was to determine the optimum conditions for vitrifying in vitro
produced day 7 porcine embryos using different vitrification devices and blastocoele collapse methods. Firstly
embryos were collapsed by micro-pipetting, needle puncture and sucrose with and without conducting
vitrification. In the next experiment, non-collapsed embryos were vitrified in an open device using either
superfine open-pulled straws (SOPS) or the CryoLoopTM system, or vitrified in a closed device using
either the CryoTipTM or Cryo BioTM’s high security vitrification system (HSV). The
post-thaw survival of embryos vitrified in the open devices did not differ significantly (SOPS: 37.3%;
CryoLoopTM: 37.3%) nor did the post-thaw survival of embryos vitrified in the closed devices
(CryoTip™: 38.5%; HSV: 42.5%). The re-expansion rate of embryos that were collapsed via micro-pipetting
(76.0%) did not differ from those that were punctured (75.0%) or collapsed via sucrose (79.6%) when
vitrification was not performed. However, embryos collapsed via sucrose solutions (24.5%) and needle puncture
(16.0%) prior to vitrification were significantly less likely to survive vitrification than the control
(non-collapsed) embryos (53.6%, P < 0.05). The findings show that both open and closed vitrification
devices were equally effective for the vitrification of porcine blastocysts. Collapsing blastocysts prior to
vitrification did not improve survival, which is inconsistent with the findings of studies in other species.
This may be due to the extremely sensitive nature of porcine embryos, and/or the invasiveness of the
collapsing procedures. 相似文献
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Major health conditions in sheep contribute to substantial economic losses throughout the sheepmeat supply chain in Australia. A systematic review was undertaken to explore the measurable impact of six conditions: arthritis, sheep measles, pleurisy, pneumonia, grass seeds and rib fractures, on the production of lamb and mutton across the meat value chain. Peer‐reviewed scientific literature from three databases and non‐peer‐reviewed articles and reports from Australian government and non‐government websites were searched between 11 and 17 November 2019. Original articles, including studies conducted in Australia and New Zealand, that had measurable impacts on conditions of interest were included. The search yielded 16 articles and reports and were classified as producer impact and/or processor impact studies. Mortalities were quantified for pneumonia and arthritis, with pneumonia having the highest impact for producers. Grass seed infestation resulted in the highest impact on carcase and liveweight losses compared to arthritis and pneumonia. Arthritis had the highest trim weight losses for both lamb and mutton and the highest rate of carcase condemnation. Grass seed was the only condition where other impacts on the processor (chain speed and staff relocation to the boning room) were quantified. Although quantifiable production and processing losses were available for some conditions, this review has highlighted that limited quantifiable data based on scientifically sound research were not available for other conditions. The evidence for some conditions found in this review can be used to target future research activities and to further assist producers in making informed management decisions on prevention and control. 相似文献