Superconductivity and magnetism are two antagonistic cooperative phenomena, and the intriguing problem of their coexistence has been studied for several decades. Recently, artificial hybrid superconductor-ferromagnet systems have been commonly used as model systems to reveal the interplay between competing superconducting and magnetic order parameters, and to verify the existence of new physical phenomena, including the predicted domain-wall superconductivity (DWS). Here we report the experimental observation of DWS in superconductor-ferromagnet hybrids using a niobium film on a BaFe(12)O(19) single crystal. We found that the critical temperature T(c) of the superconductivity nucleation in niobium increases with increasing field until it reaches the saturation field of BaFe(12)O(19). In accordance with the field-shift of the maximum value of T(c), pronounced hysteresis effects have been found in resistive transitions. We argue that the compensation of the applied field by the stray fields of the magnetic domains as well as the change in the domain structure is responsible for the appearance of the DWS and the coexistence of superconductivity and magnetism in the superconductor-ferromagnet hybrids.

No abstract

1 Chemical cues involved in host location by Dastarcus helophoroides (Fairmaire) (Coleoptera: Bothrideridae), a parasitoid of Anoplophora glabripennis Motschulsky, Monochamus alternatus Hope, Massicus raddei (Blessig), Apriona germari (Hope), Apriona swainsoni (Hope) and Batocera horsfielde (Hope) in the family Cerambycidae, were investigated in a Y-tube olfactometer. Responses of D. helophoroides adults toward odour sources from their host ( M. raddei ) and host tree ( Quercus mongolicus Fisch. ex. Turcz.) were tested in either no-choice or two-way choice tests. Wood with larval tunnels and larvae frass were attractive to D. helophoroides . Both sexes showed attraction to wood with larval tunnels. 2 Volatile chemicals emitted from wood with larval tunnels and larval frass were collected on Porapak Q and analyzed by gas chromatography-mass spectrometry. Several compounds identified from these sources, including ␣ -pinene, ␤ -pinene, ⌬ -3-carene, limonene and ␤ -myrcene, were tested against D. helophoroides in the same Y-tube olfactometer. 3 The result showed that D. helophoroides adults were attracted to ( R )-( + )-limonene, with or without the background odour from uninfested fresh wood. This may suggest that ( R )-( + )-limonene is an important kairomone for this parasitic beetle. 4 Dose-dependent response of D. helophoroides adults to ( R )-( + )-limonene indicated that D. helophoroides adults showed significant attraction to ( R )-( + )-limonene when release rates exceeded 2.08 g/h in Y-tube olfactometer tests. Moreover, significantly more A. glabripennis larvae were parasitized by D. helophoroides in the presence of R -( + )-limonene, relative to the control in cage experiments.

An efficient in vitro propagation protocol for Dendrobium candidum Wall ex Lindl. using transverse thin cell layer (tTCL) culture system was established. The frequency of shoot regeneration and the number of adventitious buds produced from the regenerated shoots significantly relied on the concentration of plant growth regulators, and the position and orientation of the explant. Murashige and Skoog (MS) medium with half-strength macronutrients and 2% sucrose, supplemented with 1.2 mg l -1 naphthaleneacetic acid (NAA) and 1.2 mg l -1 6-benzyladenine (6-BA), was optimal for shoot regeneration. Upon this medium, the youngest explant inoculated in the upright orientation exhibited a high frequency of shoot regeneration (92%), and the highest number of adventitious buds (an average of 24.5) per explant. Rooting of shoots and adventitious buds was achieved on MS medium with half-strength macronutrients and 2% sucrose with 1.0 mg l -1 NAA and 1.0 mg l -1 indole-3-acetic acid (IAA). Plantlets were transplanted into vermiculite with a 95% survival rate in a greenhouse. Ontogenetic studies revealed that the shoots originated from the stem vascular bundles.

The fall webworm, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae), is an invasive and important pest in China. Investigations on insect natural enemies have been conducted from 1996 to 1999 in five provinces and one municipality of China in order to select effective species for biological control. Two carabid predators (Coleoptera) and 25 parasitoid species were found, among which 23 were parasitic wasps (Hymenoptera), including five hyperparasitic species and two tachinid flies (Diptera). The two carabids preyed on young larvae inside webs, two braconid wasps parasitized larvae, and 18 parasitoid species attacked the fall webworm during the pupal and/or 'larval-pupal' stages. Among these parasitoids, there were one genus and nine species that are new to science and four species new to China, which were described and published by the senior author Yang. The average parasitism rates of fall webworm pupae were 25.8% and 16.1% in the overwintering generation and the first generation (summer generation), respectively. These findings reveal that these natural enemies play an important role in the natural control of the pest. Chouioia cunea Yang (Hymenoptera: Eulophidae), a gregarious pupal endo-parasitoid, was recommended as a promising biological control agent against the fall webworm in China.