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991.
Lee T. Macdonald 《Annals of science》2013,70(3):201-233
As one of his first acts upon becoming Astronomer Royal in 1835, George Airy made moves to set up a new observatory at Greenwich to study the Earth’s magnetic field. This paper uses Airy’s correspondence to argue that, while members of the reform movement in British science were putting pressure on the Royal Observatory to branch out into geomagnetism and meteorology, Airy established the magnetic observatory on his own initiative, ahead of Alexander von Humboldt’s request for British participation in the worldwide magnetic charting project that later became known as the ‘Magnetic Crusade’. That the Greenwich magnetic observatory did not become operational until 1839 was due to a series of incidental factors that provide a case study in the technical and political obstacles to be overcome in building a new government observatory. Airy attached less importance to meteorology than he did to geomagnetism. In 1840, he set up a full programme of meteorological observations at Greenwich – and thus turned his magnetic observatory into the ‘Magnetic and Meteorological department’ – only as the price of foiling an attempt by Edward Sabine and others in the London scientific elite to found a rival magnetic and meteorological observatory. Studying the origins of Airy’s Magnetic and Meteorological department highlights how important the context of other institutions and trends in science is to understanding the development of Britain’s national observatory. 相似文献
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993.
Lubka-Pathak M Shah AA Gallozzi M Müller M Zimmermann U Löwenheim H Pfister M Knipper M Blin N Schimmang T 《Cellular and molecular life sciences : CMLS》2011,68(16):2739-2749
Introduction
Tff3 peptide exerts important functions in cytoprotection and restitution of the gastrointestinal (GI) tract epithelia. Moreover, its presence in the rodent inner ear and involvement in the hearing process was demonstrated recently. However, its role in the auditory system still remains elusive. Our previous results showed a deterioration of hearing with age in Tff3-deficient animals.Results
Present detailed analysis of auditory brain stem response (ABR) measurements and immunohistochemical study of selected functional proteins indicated a normal function and phenotype of the cochlea in Tff3 mutants. However, a microarray-based screening of tissue derived from the auditory central nervous system revealed an alteration of securin (Pttg1) and serpina3n expression between wild-type and Tff3 knock-out animals. This was confirmed by qRT-PCR, immunostaining and western blots.Conclusions
We found highly down-regulated Pttg1 and up-regulated serpina3n expression as a consequence of genetically deleting Tff3 in mice, indicating a potential role of these factors during the development of presbyacusis. 相似文献994.
Patterns of colonization by macroinvertebrates were examined in two streams that differ in flow regime: a snowmelt system and a mesic groundwater system. Experiments were conducted during spring runoff, summer baseflow, and winter baseflow using artificial substrata. Colonization patterns reflected seasonal changes in benthic macroinvertebrate assemblages and life histories in each stream. The density and biomass of benthic organisms were approximately 3X greater in winter than in either spring or summer for both streams. Similarly, colonization was greater in winter than in spring or summer for both streams. In spring, colonization patterns were different between streams, with colonization being imperceptible in the snowmelt stream. Macroinvertebrate abundance fluctuated during the summer colonization experiment at both sites, resulting from a complex interplay among population emergence, recruitment, and/or movement. Assemblages in the snowmelt system primarily comprised mobile or ruderal taxa, such as Beatis tricaudatus and Chironomidae, whereas relatively sessile taxa, such as Glossoma nigrior , were predominant in the mesic groundwater system. Seasonal patterns of colonization differed among stream types primarily because of the profound interplay of flow regime and temperature on benthic community structure and organism life history. 相似文献
995.
We examined crop contents of 217 Gray Partridge ( Perdix perdix ) collected during a two-year period in eastern South Dakota. Row crop grains (corn, sunflowers) dominated late fall, winter, and spring diets. Small grains (oats, barley, wheat, rye) were rarely consumed although fields of small grains were widely available. During a severe winter when waste row crop grains were buried by snow, partridge consumed more leafy vegetation. Insects dominated the early summer diet, while foxtail ( Setaria spp.) seeds were a major late summer and early fall food. 相似文献
996.
Kalay E Yigit G Aslan Y Brown KE Pohl E Bicknell LS Kayserili H Li Y Tüysüz B Nürnberg G Kiess W Koegl M Baessmann I Buruk K Toraman B Kayipmaz S Kul S Ikbal M Turner DJ Taylor MS Aerts J Scott C Milstein K Dollfus H Wieczorek D Brunner HG Hurles M Jackson AP Rauch A Nürnberg P Karagüzel A Wollnik B 《Nature genetics》2011,43(1):23-26
Functional impairment of DNA damage response pathways leads to increased genomic instability. Here we describe the centrosomal protein CEP152 as a new regulator of genomic integrity and cellular response to DNA damage. Using homozygosity mapping and exome sequencing, we identified CEP152 mutations in Seckel syndrome and showed that impaired CEP152 function leads to accumulation of genomic defects resulting from replicative stress through enhanced activation of ATM signaling and increased H2AX phosphorylation. 相似文献
997.
998.
999.
Ageing, fitness and neurocognitive function. 总被引:18,自引:0,他引:18
A F Kramer S Hahn N J Cohen M T Banich E McAuley C R Harrison J Chason E Vakil L Bardell R A Boileau A Colcombe 《Nature》1999,400(6743):418-419
1000.