Phylogeny, taxonomics, and ovipositor length variation of the Pteromalus albipennis species group (Hymenoptera: Chalcidoidea: Pteromalidae: Pteromalinae)

Abstract The fauna of bristletails of the genus Lepismachilis Verhoeff, 1910 in Montenegro and Serbia includes only one species L. (Berlesilis) targionii (Grassi, 1887) with 2 + 2 eversible vesicles on abdominal urocoxites II–VI. Three new species of this genus are described: L. (Lepismachilis) prijepolja sp. nov., L. (Lepismachilis) limensa sp. nov. from Serbia, and L. (Lepismachilis) alexandrae sp. nov. from Montenegro. All described new species belong to the species group of the subgenus Lepismachilis s. str. with 2 + 2 eversible vesicles on abdominal urocoxites II–V. Lepismachilis prijepolja sp. nov. differs from L. y-signata Kratochvíl, 1945 and L. notata Stach, 1919 by the color, drawings and ratios of the compound eyes; ratios of sensory field on fore femur of male, number of divisions of ovipositor. Lepismachilis limensa sp. nov. differs from L. hauseri Bitsch, 1974 and L. abchasica Kaplin, 2017 by ratios of paired ocelli, sensory field on fore femur of male; ratios and chaetotaxy of maxillary and labial palps. Lepismachilis alexandrae sp. nov. differs from L. abchasica by the drawings of the compound eyes; ratios of paired ocelli, sensory field on fore femur of male; number of divisions of the parameres and gonapophyses. A list of the Machilidae occurring in Balkan Peninsula is also provided.

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On the Crystal Chemistry of Inorganic Nitrides: Crystal-Chemical Parameters and Opportunities in the Exploration of Their Compositional Space

10.26434/chemrxiv.11626974.v2 ◽

2020 ◽

Author(s):

Olivier Charles Gagné

Keyword(s):

Functional Properties ◽

A Priori ◽

Lone Pair ◽

Length Variation ◽

Electronic Effects ◽

Statistical Knowledge ◽

Redox Active ◽

Multiply Bonded ◽

Jahn Teller ◽

Compositional Space

The scarcity of nitrogen in Earth’s crust, combined with challenging synthesis, have made inorganic nitrides a relatively-unexplored class of compounds compared to their naturally-abundant oxide counterparts. To facilitate exploration of their compositional space via a priori modeling, and to help a posteriori structure verification not limited to inferring the oxidation state of redox-active cations, we derive a suite of bond-valence parameters and Lewis-acid strength values for 76 cations observed bonding to N3-, and further outline a baseline statistical knowledge of bond lengths for these compounds. We examine structural and electronic effects responsible for the functional properties and anomalous bonding behavior of inorganic nitrides, and identify promising venues for exploring uncharted compositional spaces beyond the reach of high-throughput computational methods. We find that many mechanisms of bond-length variation ubiquitous to oxide and oxysalt compounds (e.g., lone-pair stereoactivity, the Jahn-Teller and pseudo Jahn-Teller effects) are similarly pervasive in inorganic nitrides, and are occasionally observed to result in greater distortion magnitude than their oxide counterparts. We identify inorganic nitrides with multiply-bonded metal ions as a promising venue in heterogeneous catalysis, e.g. in the development of a post-Haber-Bosch process proceeding at milder reaction conditions, thus representing further opportunity in the thriving exploration of the functional properties of this emerging class of materials.

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Performance enhancement of Echo Cancellation Using a Combination of Partial Update ( PU) Methods and New Variable Length LMS (NVLLMS) Algorithm

Journal of Engineering ◽

10.31026/j.eng.2018.05.05 ◽

2018 ◽

Vol 24 (5) ◽

pp. 66

Author(s):

Thamer M. Jamel ◽

Faez Fawzi Hammood

Keyword(s):

Mean Square Error ◽

Return Loss ◽

Performance Enhancement ◽

Variable Length ◽

Echo Cancellation ◽

Convergence Time ◽

Length Variation ◽

Mean Square ◽

Step Size ◽

Echo Return Loss Enhancement

In this paper, several combination algorithms between Partial Update LMS (PU LMS) methods and previously proposed algorithm (New Variable Length LMS (NVLLMS)) have been developed. Then, the new sets of proposed algorithms were applied to an Acoustic Echo Cancellation system (AEC) in order to decrease the filter coefficients, decrease the convergence time, and enhance its performance in terms of Mean Square Error (MSE) and Echo Return Loss Enhancement (ERLE). These proposed algorithms will use the Echo Return Loss Enhancement (ERLE) to control the operation of filter's coefficient length variation. In addition, the time-varying step size is used.The total number of coefficients required was reduced by about 18% , 10% , 6%, and 16% using Periodic, Sequential, Stochastic, and M-max PU NVLLMS algorithms respectively, compared to that used by a full update method which is very important, especially in the application of mobile communication since the power consumption must be considered. In addition, the average ERLE and average Mean Square Error (MSE) for M-max PU NVLLMS are better than other proposed algorithms.

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Swamp plant communities with Salix reptans Rupr. and S. lanata L. in the west of tundra zone of Taymyr Peninsula

Vegetation of Russia ◽

10.31111/vegrus/2003.05.28 ◽

2003 ◽

pp. 28-40 ◽

Cited By ~ 1

Author(s):

L. L. Zanokha

Keyword(s):

Plant Communities ◽

Species Group ◽

Intermediate Position ◽

Tundra Zone ◽

The West ◽

Diagnostic Species ◽

New Associations ◽

Mire Vegetation ◽

Humidity Gradient ◽

Ecological Regime

The 2 new associations, Carici stantis—Salicetum reptantis and Salico-Polemonietum acutiflori, are described within the all. Caricionstantis of the class Scheuchzerio-Caricetea fuscae R. Tx. 1937 for the northern belt of the typical tundra subzone of Taymyr. The diagnostic species group of the first syntaxon includes plants typical of sites with excessive watering. The ass. Carici stantis—Salicetum reptantis is restricted to bottoms or lower parts of the watershed and mountain terrace slopes. The ecological regime of these sites is subject to slight variations reflected in presence/ absence of certain species. Due to floristic differences, the association is subdivided into several subassociations which form a topographic-ecological series along the humidity gradient: epilobietosum palustris→ptilidietosum ciliaris→typicum→petasitetosum frigidi. The ass. Carici stantis—Salicetum reptantis is referred to the all. Caricionstantis which also includes the associations Meesiotriquetris—Caricetumstantis and Pooarcticae—Dupontietumfisheri (also described from the Ragozinka R. basin); the latter occur in the wet depressions between sloping hills and the flowing valleys, respectively. If compared to these two, the ass. Carici stantis—Salicetum reptantis is shown to hold an intermediate position between them. The ass. Salico-Polemonietum acutiflori with the 2 variants, Salix lanata and S. reptans, represents various variants of mire vegetation which have undergone zoogenic transformation (by lemmings). The stands size 1—1.5 m2 in space. The diagnostic species group comprises plants common of the wet mossy stream banks. The association is referred to the all. Caricion stantis, although many diagnostic species of the alliance are not present in its composition. When the new data are available, the association is probable to be separated into an independent alliance.

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Review of species of the genus Cercyon of Russia and adjacent regions. VI. Subgenus Cercyon, the C.shinanensis group (Coleoptera: Hydrophilidae)

Zoosystematica Rossica ◽

10.31610/zsr/2019.28.2.258 ◽

2019 ◽

Vol 28 (2) ◽

pp. 258-266 ◽

Cited By ~ 1

Author(s):

S.K. Ryndevich ◽

H. Hoshina ◽

A.A. Prokin

Keyword(s):

Russian Far East ◽

Far East ◽

Species Group ◽

Palaearctic Species ◽

Diagnostic Features ◽

Kunashir Island ◽

Species Groups ◽

The Russian Far East

The Cercyon shinanensis species group with two included species is erected within the nominotypical subgenus of Cercyon Leach, 1817. This group is compared with other Palaearctic species groups of Cercyon s. str. The little-known C. shinanensis Nakane, 1965 from Japan (Honshu) is redescribed and its diagnostic features are given. Cercyon sundukovi sp. nov. is described from the Russian Far East (Kunashir Island).

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