Revision of Indian species of Baeus Haliday (Hymenoptera: Platygastroidea: Scelionidae)

ABSTRACT

Baeus senus Kozlov and Lê from Vietnam and B. primitus Rajmohana from India are the only two species of the genus known from the Oriental region. Thirty eight new species of Baeus are here described from India: B. acuminatus sp. n., B. agniparvathus sp. n., B. airavata sp. n., B. arachnophagus sp. n., B. bagheera sp. n., B. bharathiae sp. n., B. chakora sp. n., B. chitrasena sp. n., B. ciprianii sp. n., B. densipilosus sp. n., B. flaviscapus sp. n., B. gajakarna sp. n., B. giganteus sp. n., B. himalayanus sp. n., B. krishnareddyi sp. n., B. krumbiegeli sp. n., B. kubera sp. n., B. longiabdominalis sp. n., B. mahanetra sp. n., B. mareecha sp. n., B. menaka sp. n., B. nbairus sp. n., B. nicobarensis sp. n., B. pygmaeus sp. n., B. rachanae sp. n., B. rambha sp. n., B. ravana sp. n., B. reticulatus sp. n., B. sreedeviae sp. n., B. striatus sp. n., B. takshaka sp. n., B. tejaswii sp. n., B. tilottama sp. n., B. tripurasundari sp. n., B. tumburu sp. n., B. urvashi sp. n., B. vichitra sp. n. and B. xanthoclavatus sp. n. A key to the Indian species of Baeus is provided along with illustrations.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:878C5BFB-C2CB-4163-A08B-C761B4C6F087     

Quantum jumps of light recording the birth and death of a photon in a cavity

A microscopic quantum system under continuous observation exhibits at random times sudden jumps between its states. The detection of this quantum feature requires a quantum non-demolition (QND) measurement repeated many times during the system's evolution. Whereas quantum jumps of trapped massive particles (electrons, ions or molecules) have been observed, this has proved more challenging for light quanta. Standard photodetectors absorb light and are thus unable to detect the same photon twice. It is therefore necessary to use a transparent counter that can 'see' photons without destroying them. Moreover, the light needs to be stored for durations much longer than the QND detection time. Here we report an experiment in which we fulfil these challenging conditions and observe quantum jumps in the photon number. Microwave photons are stored in a superconducting cavity for times up to half a second, and are repeatedly probed by a stream of non-absorbing atoms. An atom interferometer measures the atomic dipole phase shift induced by the non-resonant cavity field, so that the final atom state reveals directly the presence of a single photon in the cavity. Sequences of hundreds of atoms, highly correlated in the same state, are interrupted by sudden state switchings. These telegraphic signals record the birth, life and death of individual photons. Applying a similar QND procedure to mesoscopic fields with tens of photons should open new perspectives for the exploration of the quantum-to-classical boundary.     

Two Earth-sized planets orbiting Kepler-20

Since the discovery of the first extrasolar giant planets around Sun-like stars, evolving observational capabilities have brought us closer to the detection of true Earth analogues. The size of an exoplanet can be determined when it periodically passes in front of (transits) its parent star, causing a decrease in starlight proportional to its radius. The smallest exoplanet hitherto discovered has a radius 1.42 times that of the Earth's radius (R(⊕)), and hence has 2.9 times its volume. Here we report the discovery of two planets, one Earth-sized (1.03R(⊕)) and the other smaller than the Earth (0.87R(⊕)), orbiting the star Kepler-20, which is already known to host three other, larger, transiting planets. The gravitational pull of the new planets on the parent star is too small to measure with current instrumentation. We apply a statistical method to show that the likelihood of the planetary interpretation of the transit signals is more than three orders of magnitude larger than that of the alternative hypothesis that the signals result from an eclipsing binary star. Theoretical considerations imply that these planets are rocky, with a composition of iron and silicate. The outer planet could have developed a thick water vapour atmosphere.     

An intracellular P2X receptor required for osmoregulation in Dictyostelium discoideum

P2X receptors are membrane ion channels gated by extracellular ATP that are found widely in vertebrates, but not previously in microbes. Here we identify a weakly related gene in the genome of the social amoeba Dictyostelium discoideum, and show, with the use of heterologous expression in human embryonic kidney cells, that it encodes a membrane ion channel activated by ATP (30-100 muM). Site-directed mutagenesis revealed essential conservation of structure-function relations with P2X receptors of higher organisms. The receptor was insensitive to the usual P2X antagonists but was blocked by nanomolar concentrations of Cu2+ ions. In D. discoideum, the receptor was found on intracellular membranes, with prominent localization to an osmoregulatory organelle, the contractile vacuole. Targeted disruption of the gene in D. discoideum resulted in cells that were unable to regulate cell volume in hypotonic conditions. Cell swelling in these mutant cells was accompanied by a marked inhibition of contractile vacuole emptying. These findings demonstrate a new functional role for P2X receptors on intracellular organelles, in this case in osmoregulation.