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Our current global food system – from food production to consumption, including manufacture, packaging, transport, retail and associated businesses – is responsible for extensive negative social and environmental impacts which threaten the long-term well-being of society. This has led to increasing calls from science–policy organizations for major reform and transformation of the global food system. However, our knowledge regarding food system transformations is fragmented and this is hindering the development of co-ordinated solutions. Here, we collate recent research across several academic disciplines and sectors in order to better understand the mechanisms that ‘lock-in’ food systems in unsustainable states.
Changing management in UK lowland pasture systems has lead to larger fertiliser inputs, increased intensity and frequency of cutting and a movement towards silage rather than hay based systems. This has lead to changes in both floral diversity and the seasonal characteristics of sward architectural complexity, which include the loss of key vegetation structures at critical times of the year. e.g., seed heads. This has had large impacts on invertebrate communities in pasture systems and is thought to be the cause of large-scale declines in both the abundances and diversity of invertebrates (Duffey et al., 1974). This decline in invertebrate abundance has also been linked to a concomitant decline in farmland bird populations reliant on invertebrates as a food sources (Vickery et al., 2001). By manipulating cattle grazing, cutting and fertiliser regimes in intensively managed pasture systems the role of vegetation structure for a variety of invertebrate communities has been investigated.
Branchiobdellidans or crayfish worms are clitellate annelids and ectosymbionts of freshwater crayfish. An investigation of branchiobdellidan infestation was undertaken in a population of endangered white-clawed crayfish (Austropotamobius pallipes) in the river Aire, UK. Thirty two percent of animals were infested either by the adult parasite or their cocoons (n=107). Parasite burden increased with host size, but did not differ with sex. Observations of crayfish gill tissue revealed a strong positive relationship between melanization of filaments and parasite prevalence and burden. Taxonomic identification revealed that 1 species of branchiobdellidan was present, Branchiobdella astaci. The first sequences were generated for this species and phylogenetically analysed alongside published sequences for 5 other branchiobdellidan species in Europe. The position of B. astaci within the genus Branchiobdella was confirmed, and it was found to cluster as a sister group to B. parasita.
A simple method for preparing radial haemolysis gels for rubella antibody screening is described. In use it gave clear zones of haemolysis when a standard serum was tested at dilutions down to 5·6 i.u./ml rubella antibody. In five lab oratories 8404 sera were screened by the method and the results were read by comparing zones of haemolysis with that of a standard serum diluted to contain 15 i.u./ml antibody. A zone ⋝ 15 i.u./ml, indicating immunity, was given by 7433 (88·4%) of the sera. No zone indicating susceptibility was seen with 748 (8·9%) sera. Small zones, < 15 i.u./ml standard, were given by 189 (2·2%) sera, and in only 34 cases (0·4%) did non-specific haemolysis interfere with the test readings. Further testing of the radial haemolysis negative and low positive sera by the haemagglutination inhibition test gave rise to some discrepant results which are discussed.
The distribution of 38 nests of loggerhead turtles (Caretta caretta) on beaches on Sanibel and Captiva islands, south-western Florida (26°26'N 82°16'W), and of 70 first digging attempts by green turtles (Chelonia mydas) on Ascension Island (7°57'S 14°22'W), was quantified. For loggerhead turtles on Sanibel and Captiva, nests were clumped close to the border between the open sand and the supra-littoral vegetation that backed the beaches. This spatial pattern of nests was closely reproduced by assuming simply that turtles crawled a random distance above the most recent high water line prior to digging. In contrast, green turtles on Ascension Island clumped their first digging attempts on the uneven beach above the springs high water line, crawling up to 80 m to reach this beach zone.
A case is presented of a laterally occurring thyroglossal cyst. In conventional teaching, thyroglossal duct remnants occupy the midline, or a position adjacent to the midline, and are found in a line marking the descent of the thyroid anlage and move upwards on protruding the tongue. Laterally presenting thyroglossal duct remnants are unusual.
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