Compilation, Calibration, and Synthesis of Faunal and Floral Radiocarbon Dates, Rancho La Brea, California

This paper presents a compilation and synthesis of calibrated radiocarbon dates for the Rancho La Brea tar pits, Los Angeles, California. A literature survey yielded 188 dates, and 21 additional dates are presented here for the first time. These range in age from 185 to 50,000 radiocarbon years. Dating of Rancho La Brea fossils has been uneven; only from Pits 91 and 2051 have more than 30 dates been obtained. The depositional history of well-sampled pits was complex, with one or more episodes of major accumulation interspersed with lower background levels of entrapment. The most significant quantifiable source of error of Rancho La Brea 14C dates is calibration error. Dates younger than 21,381 radiocarbon years can be calibrated using the IntCal04 calibration curve and yield an accurate estimate of age. Most older dates cannot be accurately calibrated at this time. Calibration of radiocarbon dates is important because raw radiocarbon dates consistently underestimate calendar dates, usually by several thousand years

A scorpion from a peatbog: the first arthropod fossil from the Late Viséan of the Moscow Coal Basin

This note describes a fossil fragment from the Upper Viséan (ca. 330 Ma), of the Moscow Coal Basin (Novgorod Region, Russia). The fossil is identified as the cuticle of a single leg segment (left femur) of a scorpion (Arachnida: Scorpiones), without any further taxonomic placement. The anatomical details of the fragment are given, along with ecological considerations. It is the first fossil scorpion record from Russia

The first molecular phylogeny of Buthidae (Scorpiones)

The first partial phylogeny of family Buthidae (17 genera) is presented, based on molecular data (16S rRNA mitochondrial DNA). The strong support for a monophyletic Old World group of 13 genera (mainly Palearctic desert forms) is demonstrated, while representative genera from Madagascar (Grosphus) and Southeast Asia (Lychas) group outside, as well as New World genera Centruroides and Rhopalurus. A very strong support is observed for the first time for three groups of Old World genera: (a) Compsobuthus, Mesobuthus, Liobuthus, Kraepelinia; (b) Hottentotta, Buthacus; (c) Orthochirus, Anomalobuthus. Phylogenetic hypotheses are discussed

Symbol Parameter Conditions Min Typ Max Unit Static characteristics

1. General description Logic level N-channel MOSFET in a D2PAK-7 package using TrenchPLUS MOSFET technology. The device includes TrenchPLUS current sensing and integrated diodes for temperature sensing. This product has been designed and qualified to AEC Q101 standard for use in high performance automotive applications. 2. Features and benefits • AEC-Q101 Compliant • Enables temperature monitoring due to integrated temperature sensor • Enables current sense measurement due to integrated current senseFET • Suitable for thermally demanding environments due to 175 °C ratin

Permian scorpions from the Petrified Forest of Chemnitz, Germany

© 2016 Dunlop et al.Background: Paleozoic scorpions (Arachnida: Scorpiones) have been widely documented from the Carboniferous Period; which hosts a remarkable assemblage of more than sixty species including both putative stem- and crown-group fossils. By contrast the succeeding Permian Period is almost completely devoid of records, which are currently restricted to a trace fossil from the early Permian of New Mexico, USA and some limb fragments from the late Permian of the Vologda Region, Russia. Results: ?Opsieobuthus tungeri sp. nov. from the Petrified Forest of Chemnitz, Germany represents the first complete body fossils of scorpions from the Permian. Explosive volcanism preserved these remarkable specimens in situ as part of the palaeosol horizon and bedrock of the Petrified Forest, immediately beneath the Zeisigwald tuff horizon. This dates to the early Permian (Sakmarian) or ca. 291 Ma. Intriguingly, the specimens were obtained from a palaeosol horizon with a compacted network of different-sized woody roots and thus have been preserved in situ in their likely life position, even within their original burrows. Differences in the structure of the comb-like pectines in the two fossils offer evidence for sexual dimorphism, and permit further inferences about the ecology and perhaps even the reproductive biology of these animals. Conclusions: As putative members of a Coal Measures genus, these fossils suggest that at least some Carboniferous scorpion lineages extended their range further into the Permian. This contributes towards a picture of scorpion evolution in which both basal and derived (orthostern) forms coexisted for quite some time; probably from the end of the Carboniferous through to at least the mid Triassic

Diversity of <i>mariner</i>-like elements in Orthoptera

Mariner-like elements (MLEs) are among the most widespread DNA transposable elements in eukaryotes. Insects were the first organisms in which MLEs were identified, however the diversity of MLEs in the insect order Orthoptera has not yet been addressed. In the present study, we explore the diversity of MLEs elements in 16 species of Orthoptera belonging to three infraorders, Acridoidea (Caelifera), Grylloidea (Ensifera), and Tettigoniidea (Ensifera) by combining data mined from computational analysis of sequenced degenerative PCR MLE amplicons and available Orthoptera genomic scaffolds. In total, 75 MLE lineages (Ortmar) were identified in all the studied genomes. Automatic phylogeny-based classification suggested that the current known variability of MLEs can be assigned to seven statistically well-supported phylogenetic clusters (I–VII), and the identified Orthoptera lineages were distributed among all of them. The majority of the lineages (36 out of 75) belong to cluster I; 20 belong to cluster VI; and seven, six, four, one and one lineages belong to clusters II, IV, VII, III, and V, respectively. Two of the clusters (II and IV) were composed of a single Orthoptera MLE lineage each (Ortmar37 and Ortmar45, respectively) which were distributed in the vast majority of the studied Orthoptera genomes. Finally, for 16 Orthoptera MLE lineages, horizontal transfer from the distantly related taxa belonging to other insect orders may have occurred. We believe that our study can serve as a basis for future researches on the diversity, distribution, and evolution of MLEs in species of other taxa that are still lacking the sequenced genomes

Results of modelling of mine ventilation with air curtain installed into downcast and upcast shafts

Existing mine air heaters (MAH) that heat the air supplied into downcast shafts during the cold period are equipped with a heat channel. A part of the air from a MAH goes through a heat channel. Another part is sucked through a pit head by general depression created by a shaft main fan. That raises a problem of mixing of two air streams, which disturbs thermal regime in the shafts and could lead to violation of safety rules, in particular, create a breach of sealing of intertubular seals. Besides, there is a concern of energy saving during ventilation at underground mining enterprises. One of the reasons for energy efficiency reduce during air supply to a mine are external leaks appeared during ventilation by a suck method. The article presents proposed solution for both problems using air curtain. During air preparation in the cold period, it is proposed to place air curtain in an air downcast shafts above the junction of a heat channel and a shaft. That is done in order to prevent air infiltration (sucking) through a pit head. According to the paper air curtain should be used in the ventilation shaft to decrease outside air leakage in order to increase energy efficiency of a main fan performance. It is determined during mathematical modelling (in SolidWorks Flow Simulation software) of ventilation and air preparation that air curtain can increase efficiency of MAH and decrease energy consumption on ventilation

The type numbers of closed geodesics

A short survey on the type numbers of closed geodesics, on applications of the Morse theory to proving the existence of closed geodesics and on the recent progress in applying variational methods to the periodic problem for Finsler and magnetic geodesicsComment: 29 pages, an appendix to the Russian translation of "The calculus of variations in the large" by M. Mors

Scorpion Biodiversity and Interslope Divergence at “Evolution Canyon”, Lower Nahal Oren Microsite, Mt. Carmel, Israel

BACKGROUND: Local natural laboratories, designated by us as the "Evolution Canyon" model, are excellent tools to study regional and global ecological dynamics across life. They present abiotic and biotic contrasts locally, permitting the pursuit of observations and experiments across diverse taxa sharing sharp microecological subdivisions. Higher solar radiation received by the "African savannah-like" south-facing slopes (AS) in canyons north of the equator than by the opposite "European maquis-like" north-facing slopes (ES) is associated with higher abiotic stress. Scorpions are a suitable taxon to study interslope biodiversity differences, associated with the differences in abiotic factors (climate, drought), due to their ability to adapt to dry environments. METHODOLOGY/PRINCIPAL FINDINGS: Scorpions were studied by the turning stone method and by UV light methods. The pattern observed in scorpions was contrasted with similar patterns in several other taxa at the same place. As expected, the AS proved to be significantly more speciose regarding scorpions, paralleling the interslope patterns in taxa such as lizards and snakes, butterflies (Rhopalocera), beetles (families Tenebrionidae, Dermestidae, Chrysomelidae), and grasshoppers (Orthoptera). CONCLUSIONS/SIGNIFICANCE: Our results support an earlier conclusion stating that the homogenizing effects of migration and stochasticity are not able to eliminate the interslope intra- and interspecific differences in biodiversity despite an interslope distance of only 100 m at the "EC" valley bottom. In our opinion, the interslope microclimate selection, driven mainly by differences in insolance, could be the primary factor responsible for the observed interslope pattern