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241.
Starting from the crisis in our communities—research has indicated it to be widely spread—the author explores the scientific tradition preceding the rise of modernism in order to draw out a more humane way of thinking that may help our contemporary societies. He discerns between two types of Renaissance humanism, one characterised by its cleverness, the other by its compassion and desire to restore dignity to the lives of people struggling to escape the clutches of medievalism. The father of the latter is Erasmus of Rotterdam and we follow the development of his conception of a social humanism as it branches out, through the work of his successors, into every scientific discipline, both natural and human. These disciplines are united by an embracing systemic idea of philosophy that unites the mind with the heart and which Erasmus called “Philosophia Christi”. We examine the two main pillars upon which this philosophy is built, love for our neighbour and education as the only legitimate instrument to change society, and the extraordinary impact it had on science and on communities living in the seventeenth century. We contrast this with the idea of power, the chosen instrument of modernity to transform society, and trace some of its tragic outcomes. We conclude by discussing the incorporation of an Erasmian type of social humanism into systems education and the future development of such programmes.  相似文献   
242.
自2011年以来,为实现培养医学生动手能力、批判性思维和创新能力的教学目标,作为基础实验课程的生物化学与分子生物学实验在实验内容和课程设置方面进行了一系列的改革,循序渐进,由浅入深,同时突出小班化精英化的教育特色,最大限度地使学生受益。在整个课程的实施过程中,生物化学与分子生物学实验室作为实践课程开展的核心部门,无论是在课程准备,课程安排,还是在教学资源分配和课程内容改革中,都起到了有利的协调和管理作用,最大限度地服务于实践教学,使实验课程在良好有序的环境中发展前行。  相似文献   
243.
An anomalous transient in the early Hubble-type (S0) galaxy Messier 85 (M85) in the Virgo cluster was discovered by Kulkarni et al. on 7 January 2006 that had very low luminosity (peak absolute R-band magnitude M(R) of about -12) that was constant over more than 80 days, red colour and narrow spectral lines, which seem inconsistent with those observed in any known class of transient events. Kulkarni et al. suggest an exotic stellar merger as the possible origin. An alternative explanation is that the transient in M85 was a type II-plateau supernova of extremely low luminosity, exploding in a lenticular galaxy with residual star-forming activity. This intriguing transient might be the faintest supernova that has ever been discovered.  相似文献   
244.
245.
LaDeau SL  Kilpatrick AM  Marra PP 《Nature》2007,447(7145):710-713
Emerging infectious diseases present a formidable challenge to the conservation of native species in the twenty-first century. Diseases caused by introduced pathogens have had large impacts on species abundances, including the American chestnut, Hawaiian bird species and many amphibians. Changes in host population sizes can lead to marked shifts in community composition and ecosystem functioning. However, identifying the impacts of an introduced disease and distinguishing it from other forces that influence population dynamics (for example, climate) is challenging and requires abundance data that extend before and after the introduction. Here we use 26 yr of Breeding Bird Survey (BBS) data to determine the impact of West Nile virus (WNV) on 20 potential avian hosts across North America. We demonstrate significant changes in population trajectories for seven species from four families that concur with a priori predictions and the spatio-temporal intensity of pathogen transmission. The American crow population declined by up to 45% since WNV arrival, and only two of the seven species with documented impact recovered to pre-WNV levels by 2005. Our findings demonstrate the potential impacts of an invasive species on a diverse faunal assemblage across broad geographical scales, and underscore the complexity of subsequent community response.  相似文献   
246.
Reproduction: the unusual suspect   总被引:1,自引:0,他引:1  
Stewart CL 《Nature》2007,450(7170):619
  相似文献   
247.
Non-volcanic tremor driven by large transient shear stresses   总被引:2,自引:0,他引:2  
Non-impulsive seismic radiation or 'tremor' has long been observed at volcanoes and more recently around subduction zones. Although the number of observations of non-volcanic tremor is steadily increasing, the causative mechanism remains unclear. Some have attributed non-volcanic tremor to the movement of fluids, while its coincidence with geodetically observed slow-slip events at regular intervals has led others to consider slip on the plate interface as its cause. Low-frequency earthquakes in Japan, which are believed to make up at least part of non-volcanic tremor, have focal mechanisms and locations that are consistent with tremor being generated by shear slip on the subduction interface. In Cascadia, however, tremor locations appear to be more distributed in depth than in Japan, making them harder to reconcile with a plate interface shear-slip model. Here we identify bursts of tremor that radiated from the Cascadia subduction zone near Vancouver Island, Canada, during the strongest shaking from the moment magnitude M(w) = 7.8, 2002 Denali, Alaska, earthquake. Tremor occurs when the Love wave displacements are to the southwest (the direction of plate convergence of the overriding plate), implying that the Love waves trigger the tremor. We show that these displacements correspond to shear stresses of approximately 40 kPa on the plate interface, which suggests that the effective stress on the plate interface is very low. These observations indicate that tremor and possibly slow slip can be instantaneously induced by shear stress increases on the subduction interface-effectively a frictional failure response to the driving stress.  相似文献   
248.
The ability of mass spectrometry to generate intact biomolecular ions efficiently in the gas phase has led to its widespread application in metabolomics, proteomics, biological imaging, biomarker discovery and clinical assays (namely neonatal screens). Matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization have been at the forefront of these developments. However, matrix application complicates the use of MALDI for cellular, tissue, biofluid and microarray analysis and can limit the spatial resolution because of the matrix crystal size (typically more than 10 mum), sensitivity and detection of small compounds (less than 500 Da). Secondary-ion mass spectrometry has extremely high lateral resolution (100 nm) and has found biological applications although the energetic desorption/ionization is a limitation owing to molecular fragmentation. Here we introduce nanostructure-initiator mass spectrometry (NIMS), a tool for spatially defined mass analysis. NIMS uses 'initiator' molecules trapped in nanostructured surfaces or 'clathrates' to release and ionize intact molecules adsorbed on the surface. This surface responds to both ion and laser irradiation. The lateral resolution (ion-NIMS about 150 nm), sensitivity, matrix-free and reduced fragmentation of NIMS allows direct characterization of peptide microarrays, direct mass analysis of single cells, tissue imaging, and direct characterization of blood and urine.  相似文献   
249.
South-polar features on Venus similar to those near the north pole   总被引:1,自引:0,他引:1  
Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright 'dipole' feature surrounded by a cold 'collar' at its north pole. The polar dipole is a 'double-eye' feature at the centre of a vast vortex that rotates around the pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a dipole feature existed at the south pole. Here we report observations of Venus' south-polar region, where we have seen clouds with morphology much like those around the north pole, but rotating somewhat faster than the northern dipole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south pole are compatible with a sulphuric acid composition.  相似文献   
250.
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