Solutions to the tethered galaxy problem in an expanding universe and the observation of receding blueshifted objects

We use the dynamics of a galaxy, set up initially at a constant proper distance from an observer, to derive and illustrate two counter-intuitive general relativistic results. Although the galaxy does gradually join the expansion of the universe (Hubble flow), it does not necessarily recede from us. In particular, in the currently favored cosmological model, which includes a cosmological constant, the galaxy recedes from the observer as it joins the Hubble flow, but in the previously favored cold dark matter model, the galaxy approaches, passes through the observer, and joins the Hubble flow on the opposite side of the sky. We show that this behavior is consistent with the general relativistic idea that space is expanding and is determined by the acceleration of the expansion of the universe -- not a force or drag associated with the expansion itself. We also show that objects at a constant proper distance will have a nonzero redshift; receding galaxies can be blueshifted and approaching galaxies can be redshifted.Comment: 8 pages including 6 figures, to appear in Am. J. Phys., 2003. Reference added in postscrip

An Interesting Correspondence: A Discussion Between C. E. W. Dorris and Miss Nora Yount (Christians) and A. E. Clement, W. H. Lovell, Chas. B. Galloway, and Geo W. Nackles (Methodists).

https://digitalcommons.acu.edu/crs_books/1092/thumbnail.jp

VESPA: software to facilitate genomic annotation of prokaryotic organisms through integration of proteomic and transcriptomic data

<p>Abstract</p> <p>Background</p> <p>The procedural aspects of genome sequencing and assembly have become relatively inexpensive, yet the full, accurate structural annotation of these genomes remains a challenge. Next-generation sequencing transcriptomics (RNA-Seq), global microarrays, and tandem mass spectrometry (MS/MS)-based proteomics have demonstrated immense value to genome curators as individual sources of information, however, integrating these data types to validate and improve structural annotation remains a major challenge. Current visual and statistical analytic tools are focused on a single data type, or existing software tools are retrofitted to analyze new data forms. We present Visual Exploration and Statistics to Promote Annotation (VESPA) is a new interactive visual analysis software tool focused on assisting scientists with the annotation of prokaryotic genomes though the integration of proteomics and transcriptomics data with current genome location coordinates.</p> <p>Results</p> <p>VESPA is a desktop Java™ application that integrates high-throughput proteomics data (peptide-centric) and transcriptomics (probe or RNA-Seq) data into a genomic context, all of which can be visualized at three levels of genomic resolution. Data is interrogated via searches linked to the genome visualizations to find regions with high likelihood of mis-annotation. Search results are linked to exports for further validation outside of VESPA or potential coding-regions can be analyzed concurrently with the software through interaction with BLAST. VESPA is demonstrated on two use cases (<it>Yersinia pestis </it>Pestoides F and <it>Synechococcus </it>sp. PCC 7002) to demonstrate the rapid manner in which mis-annotations can be found and explored in VESPA using either proteomics data alone, or in combination with transcriptomic data.</p> <p>Conclusions</p> <p>VESPA is an interactive visual analytics tool that integrates high-throughput data into a genomic context to facilitate the discovery of structural mis-annotations in prokaryotic genomes. Data is evaluated via visual analysis across multiple levels of genomic resolution, linked searches and interaction with existing bioinformatics tools. We highlight the novel functionality of VESPA and core programming requirements for visualization of these large heterogeneous datasets for a client-side application. The software is freely available at <url>https://www.biopilot.org/docs/Software/Vespa.php</url>.</p

South African National Survey of Arachnida : a checklist of the spiders (Arachnida, Araneae) of the Lekgalameetse Nature Reserve, Limpopo Province, South Africa

The aim of the South African National Survey of Arachnida (SANSA) is to document the Arachnida fauna of South Africa. One of the focus areas of SANSA is to survey protected areas to obtain species-specific information, and species distribution patterns for Red Data assessments. Here, we provide the first checklist of the spider species of Lekgalameetse Nature Reserve (LNR) in the Limpopo province of South Africa collected during five surveys between 2009 and 2016 using methods targeting both the ground and field layers. Forty-five families, represented by 168 genera and 268 species, have been collected so far. The most species-rich families were the Salticidae (41 spp.) and Araneidae (38 spp.), followed by the Thomisidae (33 spp.), while 11 families were represented by one species. Information on spider guilds, endemicity value and conservation status are provided. The LNR protects approximately 12.2% of the total South African spider fauna. Two species, Hasarinella distincta Haddad & Wesołowska, 2013 (Salticidae) and Ballomma legala Jocqué & Henrard, 2015 (Zodariidae), are presently known to be endemic to the reserve. CONSERVATION IMPLICATIONS : The LNR falls within the Savanna Biome in the Limpopo province. Only five spider species were previously known from the reserve and 263 spp. are reported from the reserve for the first time. Thirteen species are possibly new to science and 2 species represent new distribution records for South Africa.http://www.koedoe.co.za/am2017Zoology and Entomolog

South African National Survey of Arachnida: A checklist of the spiders (Arachnida, Araneae) of the Tswalu Kalahari Reserve in the Northern Cape province, South Africa

One of the aims of South African National Survey of Arachnida (SANSA) is to survey protected areas to obtain species-specific information and compile inventories to determine species distribution patterns and evaluate their conservation status for Red Data assessments. The aim of this study, the first in a series of surveys of the Diamond Route Reserves, was to compile the first checklist of the spider species in the Northern Cape at the Tswalu Kalahari Reserve. Spiders were collected during three survey periods (2005−2013) using different collecting methods to sample both the ground and field layers. In total, 32 families represented by 108 genera and 136 species have been collected so far. The most species-rich families are the Salticidae (20 spp.) and Thomisidae (18 spp.), followed by the Gnaphosidae and Araneidae (11 spp. each), while nine families are represented by singletons. The free-living wandering spiders represent 97 spp., while 39 spp. are web-builders. Information on spider guilds, endemicity value and conservation status are provided. The Tswalu Kalahari Reserve protects approximately 6.1% of the total South African spider fauna, while 24.3% of the species found in the reserve are South African endemics, of which 5.9% are Northern Cape endemics. Approximately 6.0% of the species sampled are possibly new to science or represent new records for South Africa. Conservation implications: The Tswalu Kalahari Reserve falls within the Savanna Biome in the Northern Cape province. Only one spider species was previously known from the reserve; a further 135 spp. are reported for the first time, with 5.9% of the species being Northern Cape endemics and 24.3% South African endemics. Approximately 6.0% of the species may be new to science or represent new records for South Africa