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AgSbTe2 has long been of interest for thermoelectric applications because of its favorable electronic properties and its low lattice thermal conductivity of ∼0.7W/mK. In this work, we report new findings from a high-resolution transmission electron microscopy study revealing two nanostructures in single crystal Ag1-xSb1+xSb2+x (with x=0, 0.1, 0.2); (i) a rippled natural nanostructure with a period of ∼2.5-5nm and (ii) superlattice ordered nanodomains consistent with cation ordering predicted in previous density functional theory studies. These nanostructures, combined with point-defects, probably serve as sources of scattering for phonons, thereby yielding a low lattice thermal conductivity over a wide temperature range. [ABSTRACT FROM AUTHOR]

Pselaphotumulus Owens and Carlton, gen. nov., is described as the sixth genus in the tribe Pselaphini known from New Zealand. Three new species are described: Pselaphotumulus aorerei, sp. nov., Pselaphotumulus dubius, sp. nov. and Pselaphotumulus unus, sp. nov.. Three species, Pselaphus cavelli (Broun 1893), Pselaphus oviceps (Broun 1917) and Pselaphus urquharti (Broun 1917) are transferred to Pselaphotumulus, nov. combs. Lectotypes from type series in the New Zealand Broun Collection (Natural History Museum, London) are designated for these three species. Habitus photographs, distributional maps and line drawings of diagnostic characters are provided for each species. A key to species is provided. Searches of museum collections have not yielded representatives outside of New Zealand, suggesting that this is the first endemic genus in the tribe Pselaphini described from the New Zealand's main islands, specifically, the South Island. Pselaphotumulus species exhibit restricted distribution patterns that approximately coincide with the Pacific/Indo Australian Plate boundary. [ABSTRACT FROM AUTHOR]

Three new species of pselaphine rove beetle are described from Washington--Lucifotychus lisowskii Owens and Carlton and Pselaptrichus rainierensis Owens and Carlton from Yakima County, and Tychus douglasi Owens and Carlton from Mt. Rainier National Park. These bring the total number of species in each genus to 21,38, and 37, respectively. A checklist of the North American species of each genus is provided, and the new species are integrated into previously published keys and supported by illustrations of diagnostic characters. A total of 655 specimens of Pselaphinae collected from Mt. Rainier National Park and surrounding localities from 1995 to 2009 yielded records for 19 species, including eight new records for the state of Washington. [ABSTRACT FROM AUTHOR]

Two new genera and three new species of New Zealand endemic pselaphine staphylinid beetles belonging to the supertribe Faronitae are described as follows: Chandlerea Park & Carlton, gen. nov., including C. donaldi Park & Carlton, sp. nov.; and Nunnea Park & Carlton, gen. nov., including N. johni Park & Carlton, sp. nov., and N. kuscheli Park & Carlton, sp. nov. A key to species, habitus photographs, line drawings of diagnostic characters and distribution maps for all species are provided. [ABSTRACT FROM AUTHOR]

A new endemic genus and seven new species of New Zealand pselaphine staphylinid beetles of the super-tribe Faronitae are described as follows: Pseudoexeirarthra Park & Carlton, gen. n. (type species: Sagola spinifer Broun); P. sungmini Park & Carlton, sp. n.; P. kwangguki Park & Carlton, sp. n.; P. youngboki Park & Carlton, sp. n.; P. seiwoongi Park & Carlton, sp. n.; P. parkeri Park & Carlton, sp. n.; P. hlavaci Park & Carlton, sp. n.; P. nomurai Park & Carlton, sp. n. Three species, S. spinifer Broun, S. colorata Broun, and S. puncticollis Broun, are transferred to the genus Pseudoexeirarthra. Six species are synonymized: S. dilucida Broun, S. guinnessi Broun, S. longicollis Broun, S. longula Broun, and S. rectipennis Broun under P. spinifer (Broun); S. insueta Broun under S. colorata (Broun). A lectotype is designated for P. spinifer (Broun). A key, habitus photographs, line drawings of diagnostic characters, and distribution maps are provided for each species. [ABSTRACT FROM AUTHOR]

Approximately 9,100 species belonging to the staphylinid beetle subfamily Pselaphinae have been described based on adults, but the larvae of only 19 species and 15 genera have been described in sufficient detail for systematic study, and the pupa of only a single species has been described. Larvae of the euplectine tribe Mayetiini (152 species, all in the genus Mayetia) have not been described previously. The larva and pupa of Mayetia pearsei Schuster et al. are described herein based on two larvae, a cast exuvium, and five pupae from soil wash samples containing numerous adults of the species. Larvae are distinguished from other described larvae of pselaphines based on the following combination of characters: eversible frontal vesicle simple, sac-like, with fine, dense terminal papillae; stemmata absent; epicranial stem absent; antenna two segmented, segment two bearing unbranched, elongate, sinuate sensorium; mesothoracic spiracle with large, fusiform peritreme; abdominal spiracles absent; A9 with V-shaped, apical emargination between short, fixed urogomphi. Pupae are similar to those of the European pselaphine Plectophloeus fischeri (Aubé) in having elongate prothoracic setate processes and spinose tubercles covering the antennae. The pupal description may represent the smallest coleopteran pupa described to date. Larvae and pupae of M. pearsei were found during July and August, whereas adults were found July-October in loamy sand in the floodplain of the Meramec River, Crawford County, MO. [ABSTRACT FROM AUTHOR]

Approximately 8,900 species of the staphylinid beetle subfamily Pselaphinae have been described, based on adults, but the larvae of only 18 species and 14 genera have been described in sufficient detail for systematic study. The larva of Pselaphophus atriventris (Westwood) (Staphylinidae: Pselaphinae: Pselaphini) is described herein based on a series collected in a pasture habitat in New Zealand. Larvae are distinguished from other described larvae of pselaphines based on the following combination of characters: antennal segment two bearing two trifid setiform sensoria and labrum with irregularly arranged short spines and setiferous tubercles. It is most similar to the larva of Pselaphus heisei Herbst, sharing the following characters: antenna with two subapical branched sensoria, femora tuberculate, and tibiae with ventral row of minute teeth in proximal one third. P. atriventris is introduced to New Zealand and may be widespread in the country in open habitats. Seasonal data indicate that the species is univoltine. Larvae were found during late September-November (early summer), whereas adults are found year-round, but they were most abundant June-December. A list of the described immature stages of Pselaphinae is included. [ABSTRACT FROM AUTHOR]

A new genus of the braconid subfamily Cardiochilinae, Ophiclypeus gen. nov., is described and illustrated based on three new species: O. chiangmaiensis Kang, sp. nov. type species (type locality: Chiang Mai, Thailand), O. dvaravati Ghafouri Moghaddam, Quicke & Butcher, sp. nov. (type locality: Saraburi, Thailand), and O. junyani Kang, sp. nov. (type locality: Dalin, Taiwan). We provide morphological diagnostic characters to separate the new genus from other cardiochiline genera. A modified key couplet (couplet 5) and a new key couplet (couplet 16) are provided with detailed images for Dangerfield's key to the world cardiochiline genera to facilitate recognition of Ophiclypeus gen. nov. [ABSTRACT FROM AUTHOR]

The ability to direct bimetallic nanoparticles to express desirable surface composition is a crucial step toward effective heterogeneous catalysis, sensing, and bionanotechnology applications. Here we report surface composition tuning of bimetallic Au–Pt electrocatalysts for carbon monoxide and methanol oxidation reactions. We establish a direct correlation between the surface composition of Au–Pt nanoparticles and their catalytic activities. We find that the intrinsic activities of Au–Pt nanoparticles with the same bulk composition of Au0.5Pt0.5 can be enhanced by orders of magnitude by simply controlling the surface composition. We attribute this enhancement to the weakened CO binding on Pt in discrete Pt or Pt-rich clusters surrounded by surface Au atoms. Our finding demonstrates the importance of surface composition control at the nanoscale in harnessing the true electrocatalytic potential of bimetallic nanoparticles and opens up strategies for the development of highly active bimetallic nanoparticles for electrochemical energy conversion. [ABSTRACT FROM AUTHOR]

Abstract: Two species of bark lice, Xanthocaecilius sommermanae Mockford and Polypsocus corruptus Hagen, collected in a canopy Malaise trap placed in Great Smoky Mountains National Park as part of a survey of the park’s fauna, were found to be infected with microsporidia. Diagnosis was originally based on light microscopy, and was confirmed by PCR amplification and electron microscopy. This is the first record of microsporidia infection in the insect order Psocoptera. Four morphological spore types corresponded to four original SSUrDNA sequences (Genbank accession no. FJ865221-24), suggesting infection with four microsporidia species. Two of those species were examined by electron microscopy. We describe here one new genus and two new species based on morphological and sequence data: Antonospora psocopterae sp. n. with elongated diplokaryotic spores, 4.4±0.05×1.9±0.03μm and Mockfordia xanthocaeciliae gen. n. sp. n. with ovocylindrical monokaryotic spores, 2.5±0.10×1.4±0.02μm. A. psocopterae displayed high sequence (95%) and structural similarity with Antonospora scoticae, fell within a well supported dichotomy with A. scoticae inside the Antonospora–Paranosema clade in phylogenetic analyses by NJ, PS and ML. M. xanthocaeciliae did not exhibit much sequence or structural similarity with any of known microsporidia species, except Encephalitozoon spp. M. xanthocaeciliae fell within one clade with Encephalitozoon spp. in phylogenies and shared with encephalitozoons structural resemblance and about 80% of SSUrDNA sequence identity. The other two species were not described and provisionally were placed to the collective genus Microsporidium as Microsporidium sp. 1 and Microsporidium sp. 4 from bark lice because of insufficient morphological data. The finding that samples fixed and stored for months in propylene glycol (“antifreeze”) are good enough for DNA sequence analysis and can be used for morphological analyses (if no better fixation alternatives are available), is promising for future surveys for microsporidia. [Copyright &y& Elsevier]

Abstract: Ninety three bumble bees belonging to the genus Bombus, subgenus Pyrobombus (three Bombus vagans, seven Bombus bimaculatus, 17 B. sandersoni and 68 B. impatiens) from Great Smoky Mountains National Park were examined for microsporidia. Light microscopy of calcoflour and trichrome-stained smears, and PCR revealed infection with N. bombi in one specimen each of B. sandersoni and B. impatiens. Sizes and shapes of spores in both N. bombi isolates were similar to those described for European isolates of the microsporidium. A region of the rRNA gene from the B. impatiens isolate (1689bp, accession GQ254295) aligned with homologous sequences from eight European isolates, with only three variable sites. Sequence variability of this region between novel isolates and the European ones was the same as among European isolates. [Copyright &y& Elsevier]