Plasma replacement for in vitro culture of Plasmodium knowlesi

Of six fractions of human plasma tested, only Cohn's fraction IV-4 was effective for the replacement of whole plasma from monkey (Macaca mulatta) for the in vitro culture of Plasmodium knowlesi. The effects observed on multiplication and morphology of parasites suggest a specific role of some substance or substances in fraction IV-4.     

Molecular and morphological supertrees for eutherian (placental) mammals

A large body of diverse comparative data now exists for a major phylogenetic synthesis of the higher-level relationships among eutherian (placental) mammals. We present such a phylogenetic synthesis using the composite trees or supertrees from the combined and separate analyses of their published molecular and morphological source phylogenies. Our combined and separate supertrees largely support the same suprafamilial taxa and orders, but different interordinal clades. These similarities and differences reinforce the continuing contributions of morphological studies, while highlighting the growing influence of molecular information on the field. As current summaries of past research, our supertrees emphasize opportunities for future work, while providing a step toward the eventual integration of the data and characters themselves.     

Odd-parity superconductivity in Sr2RuO4

Phase-sensitive measurements were made on Sr2RuO4 to establish unambiguously the odd-parity pairing in this material. The critical current of Au(0.5)In(0.5)-Sr2RuO4 superconducting quantum interference devices prepared on Sr2RuO4 single crystals was found to be a maximum for devices with junctions on the same side of the crystal and a minimum for devices with junctions on opposite sides, in the limit of zero magnetic flux; these findings indicate that the phase of the superconducting order parameter in Sr2RuO4 changes by pi under inversion. This result verifies the odd-parity pairing symmetry and the formation of spin-triplet Cooper pairs in Sr2RuO4.     

拟南芥在植物抗病性分子机制研究中的作用

植物对病原物的抗性是一个很复杂的生命现象。目前人们认识到植物的抗病过程有很多基因和一些相互关联的信号传导途径参与。人们对植物抗病的分子机制的了解,很多是来自以拟南芥作为材料所进行的大量研究。对植物抗病性的了解是一步步深入的,其进展与研究方法和技术的不断改革密不可分,其中实验材料的模式化使得研究更加集中、更具有通用性,所使用的资源更丰富,强有力地推进了研究的深入进行。在此,对拟南芥这个模式植物在植物抗病性的遗传和分子机制研究中的作用做了阐述。     

Emission of coherent THz radiation from superconductors

Compact solid-state sources of terahertz (THz) radiation are being sought for sensing, imaging, and spectroscopy applications across the physical and biological sciences. We demonstrate that coherent continuous-wave THz radiation of sizable power can be extracted from intrinsic Josephson junctions in the layered high-temperature superconductor Bi2Sr2CaCu2O8. In analogy to a laser cavity, the excitation of an electromagnetic cavity resonance inside the sample generates a macroscopic coherent state in which a large number of junctions are synchronized to oscillate in phase. The emission power is found to increase as the square of the number of junctions reaching values of 0.5 microwatt at frequencies up to 0.85 THz, and persists up to approximately 50 kelvin. These results should stimulate the development of superconducting compact sources of THz radiation.