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91.
Metal chelates, quaternary salts and hydrochlorides of 3,4,5,-tetramethyl-1,10-phenanthroline are bactericidal to E. rhusiopathiae and F. nodosus; for the metal chelates, the rank order of speed of bactericidal action against E. rhusiopathiae is Cu(II) > Fe(Ii) = Ni(II) ≥ Ru(II) > Zn(II) > Mn(II) = Co(II). E. rhusiopathiae does not develop significant resistance to the Cu(II) chelate. The unusual susceptibility of F. nodosus to the Co(II) chelate and the possible uses of such metal chelates in veterinary practice are discussed.  相似文献   
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A new species of sphaerosporid myxosporean, Sphaerospora elwhaiensis sp. n., is described from kidney of non-anadromous sockeye salmon (kokanee) Oncorhynchus nerka (Walbaum) from Lake Sutherland in the northern Olympic Peninsula, Washington, USA. Infection with the parasite was detected in 45% of 177 kokanee examined over 5 years. While conforming to the morphological criteria by which members of the genus are defined, the parasite is distinguished from congeners in salmonids of western North America by a unique combination of valvular sculpting of the myxospore, the relatively large size of the myxospore and monosporous development within the pseudoplasmodium. In addition, nucleotide sequences of the parasite's small and large subunit ribosomal RNA gene are unique. Phylogenetic analyses of these sequences suggested that the parasite is most closely related to freshwater Myxidium spp. and Zschokkella spp. The molecular data have provided further evidence for a polyphyletic association previously recognized among members of the genus and emphasize the need for a taxonomic revision of Sphaerospora Thélohan, 1892 and related genera.  相似文献   
94.
This paper examines the relation between visitor behaviour and certain features of a number of major green spaces in the city of Granada, south-eastern Spain, focussing on key urban, ecological and landscape-related issues. Information on user profiles and numbers, the various uses made of these areas, their design, plant species richness and local urban and sociological background, was collected by means of in situ observation in a total of ten urban green spaces with surface areas of over 5000 m2. Findings indicated that these spaces were used largely for purposes directly related to well-being: recreational and sporting activities, socialising, or simply relaxing. Interestingly, the most common activities in each space were governed by features intrinsic to the space itself: accessibility, design, maintenance and plant richness and distribution, all of which affected the health-related attributes and aesthetic value of the space. The study also highlighted a number of serious deficiencies in certain green spaces, which will need to be addressed in future action plans and replanning projects as an essential step in ensuring that they meet the real needs and expectations of the target population. The information provided by this research may prove particularly valuable for improving the systemic functions of green spaces in Mediterranean cities sharing similar bioclimatic and sociological features, and for ensuring that they fulfil the role assigned to green spaces in sustainable cities.  相似文献   
95.
  1. The worldwide decline of marine forests, due to human impacts and climate change, emphasizes the need to develop and implement effective and sustainable solutions to restore these endangered habitats and to re-establish the services they provide.
  2. In this study, the ex situ restoration of Gongolaria barbata (=Treptacantha barbata), a Mediterranean subtidal habitat-forming species of brown seaweed, was for the first time implemented in a marine protected area in the Adriatic Sea. Two restoration efforts were performed in 2019. The first was started in winter, after a marine heatwave that triggered early fertility, and the second in spring, when the species usually reproduces.
  3. This study aimed to evaluate: (i) the disruptive effects of a thermal anomaly on the reproductive biology and performance in culture of G. barbata; and (ii) the impact of the grazing pressure on juveniles after the outplanting.
  4. The first cultivation was more productive than the second, in terms of zygote release and germling growth. To mitigate the low efficiency of the second culture and to avoid prolonged highly demanding maintenance in the mesocosms, the cultivation period was extended outdoors using a structure suspended in the water column.
  5. The modular frames conceived for outplanting G. barbata proved to be effective because of their easy operability and low cost. Controlling for herbivorous fish had significant positive effects on both juvenile survival and growth.
  6. The outcomes highlighted that an unpredictable climatic event and fish grazing were major threats that impaired the restoration process of G. barbata. These stressors should be considered when developing plans to implement effective large-scale restoration of canopy-forming macroalgae.
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This study reports the prevalence of Cryptosporidium, Giardia and Isospora species in cats showing signs of gastrointestinal disease. Records from a United Kingdom commercial diagnostic laboratory between December 2003 and December 2005 were reviewed. Of 1355 cats, Cryptosporidium species oocysts were found in 13 cats (1%), Giardia species trophozoites in 74 (6%), and Isospora felis oocysts in 46 (3%). In a second group of 48 cats, prevalence of Giardia species was 15% using an immunoassay for detection of antigen compared to 4% detected with microscopy. Prevalence of Giardia (9%) and Isospora (9%) species was higher in cats less than 6 months old. Gender and breed did not affect prevalence. There was a trend for Cryptosporidium and Isospora species infections to be detected in late autumn and early winter. Regional differences in prevalence were not detected. None of these organisms show a characteristic pattern of clinical signs. This study demonstrates that enteric protozoal infection is common in domestic cats showing signs of alimentary disease.  相似文献   
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Three enzyme systems (2 amylase‐based and 1 protease‐based) were tested in shelf‐stable bread to determine effectiveness in preserving texture during storage for eight weeks. Each enzyme was tested in formulations without glycerol or with 6% glycerol. Bread samples were analyzed to determine physical properties (crumb density, crust‐to‐crumb ratio, rate of moisture distribution from crumb to crust), mechanical properties (modulus, and a parameter [C1] describing resistance to high levels of deformation obtained by fitting stress‐strain data to a three‐parameter function), and thermal properties (thermal stability and enthalpy of transitions) as a function of storage time. Mechanical properties were further analyzed to predict asymptotic firmness. Bread firmness after storage as evaluated in terms of modulus and C1 were lower in all enzyme‐added systems, the effect of protease being the most significant. Enzymes had less effect on glycerol‐containing systems with no apparent trend. The breads had complex thermal behavior and exhibited multiple transitions. Both amylase preparations in the presence of glycerol reduced the amount of starch recrystallization.  相似文献   
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