Cryptic grey-bellied dunnart (Sminthopsis griseoventer) discovered in South Australia: genetic, morphological and subfossil analyses show the value of collecting voucher material

2011 ◽  
Vol 59 (3) ◽  
pp. 127 ◽  
Author(s):  
Catherine M. Kemper ◽  
Steven J. B. Cooper ◽  
Graham C. Medlin ◽  
Mark Adams ◽  
David Stemmer ◽  
...  

The assumption that almost all mammal species are known to science has led to a recent trend away from collecting voucher specimens/tissues during field studies. Here we present a case study of a recently discovered cryptic marsupial (Sminthopsis griseoventer) in South Australia (SA) and show how such collections can contribute to rigorous biodiversity and biogeographic assessments. Morphological and genetic (allozyme and mitochondrial control region (CR) sequence data) analyses, including ancient DNA analyses of type material, were applied to 188 voucher specimens and 94 non-vouchered tissues of Sminthopsis held at the SA Museum. These data were used to confirm the presence of S. griseoventer in SA, validate means of identifying it morphologically and describe recent and pre-European distributions. Pelage differences between S. griseoventer and S. dolichura enabled their identification, but external measurements overlapped considerably. Subfossil S. griseoventer were identified from seven deposits and confirmed that in the past the species was more widespread in SA. CR divergences (>1.8%) among Western Australian and SA S. griseoventer suggested its long-term presence in SA. Discrepancies between the mitochondrial and allozyme affinities of S. aitkeni and S. griseoventer, coupled with the lack of obvious morphological differences, indicate that a taxonomic reappraisal of these species is warranted. The study strongly demonstrates an ongoing need for the routine collection of mammal voucher material in biological and environmental impact surveys.

2006 ◽  
Vol 19 (3) ◽  
pp. 211 ◽  
Author(s):  
Stephen D. Hopper ◽  
Andrew P. Brown

We uphold the generic rank of Paracaleana on the basis of its divergent pollination syndrome (sexual deception of male thynnid wasps compared with pollination of Caleana by male sawflies), recent DNA sequence data demonstrating monophyly, and nomenclatural stability. Ten of the 13 species recognised herein are new, all endemic to the South-west Australian Floristic Region: Paracaleana alcockii, P. brockmanii, P. dixonii, P. gracilicordata, P. granitica, P. hortiorum, P. lyonsii, P. parvula, P. terminalis and P. triens. Although some of these taxa have subtle morphological differences, primarily of labellum morphology, evidence from other Australian orchid genera whose flowers sexually deceive wasp pollinators indicates that reproductive isolation is probable among close sister taxa in Paracaleana. Moreover, phenological, ecological and geographical differences help separate morphologically close sister taxa. P. disjuncta D.L. Jones is considered to extend from Victoria and South Australia west into the South-west Australian Floristic Region, where James Drummond first collected the species, probably in 1838. Additional research is needed on pollinators, molecular phylogeny, possibly undescribed taxa within P. nigrita and on the few putative hybrids identified in the genus.


Author(s):  
В. А. Batasheva ◽  
R. А. Abdullaev ◽  
Е. Е. Radchenko ◽  
О. N. Kovaleva, ◽  
I. А. Zveynek

At the Dagestan experimental station, 360 samples of barley were studied from the world gene pool of the VIR named after NI Vavilov.  The sample was represented by 2- and 6-row, winter and spring, of different eco-geographical origin forms of culture. As a result of the long-term laboratory-field studies, samples with a productivity of more than 500 g / m2 were identified with an average sample size of 200-400 g. The Isp value of the noted varieties >1, therefore, they can be classified as ecologically plastic varieties. Samples of double-row barley are morphologically characterized by a combination of increased productive bushiness with a smaller number of spikelets, respectively, and grains in the ear than the six-row barley.  Theoretically, one would expect that with the development of plants and the formation of a crop under favorable conditions, low productive bushiness of 6-row forms is compensated by a large number of spikelets and grains in the ear; a smaller number of spikelets and grains in the ear in 2-row rows - high productive bushiness. At the same time, the significance of morphological differences in subspecies in the formation of their final productivity would not be significant. However, in the study area, six-rowed barley is more affected by the widespread Swedish fly (the factor that limits crop yield in the region) than double-rowed and in general the samples of the distichon L. subspecies exceed those of vulgare L. over the final crop. The frequency of occurrence of productive forms is higher among two-row barley. On the basis of the analysis of the results of many years of research, taking into account that the factors affecting the harvest of barley in this zone are plant damage caused by fungal diseases, damage to the Swedish fly, lodging, and salinization, we consider it economically more efficient to cultivate, in conditions of irrigated farming, southern Dagestan  with the corresponding characteristics.


Author(s):  
О. V. Levakova ◽  
L. М. Eroshenko ◽  
А. N. Eroshenko

The article presents and analyzes data of competitive varietal testing of promising varieties and lines of spring barley for yield and brewing qualities. Field studies were conducted in 2014–2017 on dark gray forest heavy loam soil. Agrochemical parameters are total nitrogen – 0.24%, humus content in a layer of 0-40 cm (according to Tyurin) – 5.19%, hydrolysis nitrogen – 123.5 mg / kg, salt extract pH – 4.92 mg-eq / 100g; labile phosphorus - 34.6 mg / 100g, labile potassium – 20.0 mg / 100g. The forerunner is winter wheat. Meteorological conditions in the years of research differed from each other and from the average long-term value. Barley samples were assessed by the protein content in the grain (GOST 10846-91), extract content (GOST 12130-77), weight 1000 grains (GOST 10842-89). Ecological plasticity was determined by the method proposed by E.D. Nettevich, A.I. Morgunov and M.I. Maksimenko, stability index (Ľ) by A. A. Gryaznov, indicator of stability level (Puss) by E. D. Nettevich and A. I. Morgunov. The main measure for assessing quality indicators is protein content. Many other biochemical and technological features of grain depend on its level. The experimental data convincingly testify to the significant influence of the soil and climatic conditions on the yield and, especially, on the brewing qualities of barley in the conditions of the Central Region of the Nonchernozem Zone. According to the studied traits, new valuable varieties Nadezhny, Sir, Noble and selection lines 141 / 1-09 h 746, 23 / 1-10 h 784, distinguished by high adaptability and resistance to adverse environmental factors, have been identified.


2020 ◽  
Vol 133 (3) ◽  
pp. 758-764
Author(s):  
Eung Koo Yeon ◽  
Young Dae Cho ◽  
Dong Hyun Yoo ◽  
Su Hwan Lee ◽  
Hyun-Seung Kang ◽  
...  

OBJECTIVEThe authors conducted a study to ascertain the long-term durability of coiled aneurysms completely occluded at 36 months’ follow-up given the potential for delayed recanalization.METHODSIn this retrospective review, the authors examined 299 patients with 339 aneurysms, all shown to be completely occluded at 36 months on follow-up images obtained between 2011 and 2013. Medical records and radiological data acquired during the extended monitoring period (mean 74.3 ± 22.5 months) were retrieved, and the authors analyzed the incidence of (including mean annual risk) and risk factors for delayed recanalization.RESULTSA total of 5 coiled aneurysms (1.5%) occluded completely at 36 months showed recanalization (0.46% per aneurysm-year) during the long-term surveillance period (1081.9 aneurysm-years), 2 surfacing within 60 months and 3 developing thereafter. Four showed minor recanalization, with only one instance of major recanalization. The latter involved the posterior communicating artery as an apparent de novo lesion, arising at the neck of a firmly coiled sac, and was unrelated to coil compaction or growth. Additional embolization was undertaken. In a multivariate analysis, a second embolization for a recurrent aneurysm (HR = 22.088, p = 0.003) independently correlated with delayed recanalization.CONCLUSIONSAlmost all coiled aneurysms (98.5%) showing complete occlusion at 36 months postembolization proved to be stable during extended observation. However, recurrent aneurysms were predisposed to delayed recanalization. Given the low probability yet seriousness of delayed recanalization and the possibility of de novo aneurysm formation, careful monitoring may be still considered in this setting but at less frequent intervals beyond 36 months.


Author(s):  
Liang Cheng ◽  
Xudong Han ◽  
Zijun Zhu ◽  
Changlu Qi ◽  
Ping Wang ◽  
...  

Abstract Since the first report of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in December 2019, the COVID-19 pandemic has spread rapidly worldwide. Due to the limited virus strains, few key mutations that would be very important with the evolutionary trends of virus genome were observed in early studies. Here, we downloaded 1809 sequence data of SARS-CoV-2 strains from GISAID before April 2020 to identify mutations and functional alterations caused by these mutations. Totally, we identified 1017 nonsynonymous and 512 synonymous mutations with alignment to reference genome NC_045512, none of which were observed in the receptor-binding domain (RBD) of the spike protein. On average, each of the strains could have about 1.75 new mutations each month. The current mutations may have few impacts on antibodies. Although it shows the purifying selection in whole-genome, ORF3a, ORF8 and ORF10 were under positive selection. Only 36 mutations occurred in 1% and more virus strains were further analyzed to reveal linkage disequilibrium (LD) variants and dominant mutations. As a result, we observed five dominant mutations involving three nonsynonymous mutations C28144T, C14408T and A23403G and two synonymous mutations T8782C, and C3037T. These five mutations occurred in almost all strains in April 2020. Besides, we also observed two potential dominant nonsynonymous mutations C1059T and G25563T, which occurred in most of the strains in April 2020. Further functional analysis shows that these mutations decreased protein stability largely, which could lead to a significant reduction of virus virulence. In addition, the A23403G mutation increases the spike-ACE2 interaction and finally leads to the enhancement of its infectivity. All of these proved that the evolution of SARS-CoV-2 is toward the enhancement of infectivity and reduction of virulence.


2021 ◽  
pp. 1-37
Author(s):  
Michał Burzyński ◽  
Frédéric Docquier ◽  
Hendrik Scheewel

Abstract In this paper, we investigate the long-term effects of climate change on the mobility of working-age people. We use a world economy model that covers almost all the countries around the world, and distinguishes between rural and urban regions as well as between flooded and unflooded areas. The model is calibrated to match international and internal mobility data by education level for the last 30 years, and is then simulated under climate change variants. We endogenize the size, dyadic, and skill structure of climate migration. When considering moderate climate scenarios, we predict mobility responses in the range of 70–108 million workers over the course of the twenty-first century. Most of these movements are local or inter-regional. South–South international migration responses are smaller, while the South–North migration response is of the “brain drain” type and induces a permanent increase in the number of foreigners in OECD countries in the range of 6–9% only. Changes in the sea level mainly translate into forced local movements. By contrast, inter-regional and international movements are sensitive to temperature-related changes in productivity. Lastly, we show that relaxing international migration restrictions may exacerbate the poverty effect of climate change at origin if policymakers are unable to select/screen individuals in extreme poverty.


2021 ◽  
Vol 13 (15) ◽  
pp. 8316
Author(s):  
Camelia Mirela Baba ◽  
Constantin Duguleană ◽  
Marius Sorin Dincă ◽  
Liliana Duguleană ◽  
Gheorghița Dincă

The Covid-19 induced economic crisis has significantly affected almost all businesses from nearly every sector, causing severe financial problems, lack of cash assets, and decrease of revenues. In this context, the economic entities were forced to look for adjustment and rescue solutions of their activities. One possible solution for the recovery and reorganization of economic entities’ activities is demerger. This paper evaluates the impact of demerger upon the sustainable development of economic entities in terms of economic efficiency and financial performances. To achieve this goal, a statistical analysis of profitability ratios before and after the demerger, as well as a structural analysis of 268 demerger projects for the April 2012–April 2021 period, were performed. The results attest there are no significant differences between the ex-ante and ex-post financial performances. However, demerger seems to have a positive effect upon analyzed companies helping them to overcome economic hardships, rethink their business strategies, and continue their activity in the medium and long-term time horizon.


2021 ◽  
Vol 22 (9) ◽  
pp. 4315
Author(s):  
Marta Puchta ◽  
Jolanta Groszyk ◽  
Magdalena Małecka ◽  
Marek D. Koter ◽  
Maciej Niedzielski ◽  
...  

Seed aging is a complex biological process that has been attracting scientists’ attention for many years. High-throughput small RNA sequencing was applied to examine microRNAs contribution in barley seeds senescence. Unique samples of seeds that, despite having the same genetic makeup, differed in viability after over 45 years of storage in a dry state were investigated. In total, 61 known and 81 novel miRNA were identified in dry seeds. The highest level of expression was found in four conserved miRNA families, i.e., miR159, miR156, miR166, and miR168. However, the most astonishing result was the lack of significant differences in the level of almost all miRNAs in seed samples with significantly different viability. This result reveals that miRNAs in dry seeds are extremely stable. This is also the first identified RNA fraction that is not deteriorating along with the loss of seed viability. Moreover, the novel miRNA hvu-new41, with higher expression in seeds with the lowest viability as detected by RT-qPCR, has the potential to become an indicator of the decreasing viability of seeds during storage in a dry state.


Mammalia ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Adrien André ◽  
Johan Michaux ◽  
Jorge Gaitan ◽  
Virginie Millien

Abstract Rapid climate change is currently altering species distribution ranges. Evaluating the long-term stress level in wild species undergoing range expansion may help better understanding how species cope with the changing environment. Here, we focused on the white-footed mouse (Peromyscus leucopus), a widespread small mammal species in North-America whose distribution range is rapidly shifting northward. We evaluated long-term stress level in several populations of P. leucopus in Quebec (Canada), from the northern edge of the species distribution to more core populations in Southern Quebec. We first tested the hypothesis that populations at the range margin are under higher stress than more established populations in the southern region of our study area. We then compared four measures of long-term stress level to evaluate the congruence between these commonly used methods. We did not detect any significant geographical trend in stress level across our study populations of P. leucopus. Most notably, we found no clear congruence between the four measures of stress level we used, and conclude that these four commonly used methods are not equivalent, thereby not comparable across studies.


1988 ◽  
Vol 133 ◽  
pp. 461-464
Author(s):  
O.J. Sovers ◽  
C.D. Edwards ◽  
C.S. Jacobs ◽  
G.E. Lanyi ◽  
R.N. Treuhaft

Intercontinental dual-frequency radio interferometric measurements were carried out during 1978 to 1985 between NASA's Deep Space Network stations in California, Spain, and Australia. Analysis of 6800 pairs of delay and delay rate observations made during 51 sessions produced a catalog of positions of 106 extragalactic radio sources, fairly uniformly distributed over the celestial sphere between −45° and +85° declination. Almost all of the resulting source positions have formal uncertainties between 0.5 and 3 milliarcseconds, with their distributions peaking somewhat below 1 mas. Root-mean-square uncertainties are 2.1 and 2.0 mas for RA and declination, respectively. Evidence is found for a long-term drift of the Earth's rotation axis in inertial space, relative to the 1984 IAU precession and nutation models. Tests for time variability of positions of 32 frequently observed sources place limits at the 1 mas/yr level. Comparisons with independently determined source catalogs of comparable quality show differences of positions of common sources that amount to a few mas, and may indicate the level of systematic errors in VLBI source position measurements.


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