Distinctive compositional characteristics and evolutionary trend of Precambrian glaucony: Example from Bhalukona Formation, Chhattisgarh basin, India

2015 ◽  
Vol 271 ◽  
pp. 33-48 ◽  
Author(s):  
Santanu Banerjee ◽  
Saikat Mondal ◽  
Partha Pratim Chakraborty ◽  
S.S. Meena
2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Consuele Morrone ◽  
Fabio Ietto

AbstractThis contribution focuses on a multidisciplinary research showing the geomorphological evolution and the beach sand composition of the Tyrrhenian shoreline between Capo Suvero promontory and Gizzeria Lido village (Calabria, southern Italy). The aim of the geomorphological analysis was to reconstruct the evolutionary shoreline stages and the present-day sedimentary dynamics along approximately 6 km of coastline. The results show a general trend of beach nourishment during the period 1870–2019. In this period, the maximum shoreline accretion value was estimated equal to + 900 m with an average rate of + 6.5 m/yr. Moreover, although the general evolutionary trend is characterized by a remarkable accretion, the geomorphological analysis highlighted continuous modifications of the beaches including erosion processes. The continuous beach modifications occurred mainly between 1953 and 1983 and were caused mainly by human activity in the coastal areas and inside the hydrographic basins. The beach sand composition allowed an assessment of the mainland petrological sedimentary province and its dispersal pattern of the present coastal dynamics. Petrographic analysis of beach sands identified a lithic metamorphi-clastic petrofacies, characterized by abundant fine-grained schists and phyllites sourced from the crystalline terrains of the Coastal Range front and carried by the Savuto River. The sand is also composed of a mineral assemblage comparable to that of the Amato River provenance. In terms of framework detrital constituents of QFL (quartz:feldspars:aphanitic lithic fragments) and of essential extraclasts, such as granitoid:sedimentary:metamorphic phaneritic rock fragments (Rg:Rs:Rm), sand maturity changes moderately from backshore to shoreface, suggesting that transport processes had a little effect on sand maturity. Moreover, the modal composition suggests that the Capo Suvero promontory does not obstruct longshore sand transport from the north. Indeed, sands displaced by currents driven by storm-wave activity bypass this rocky headland.


OP-Journal ◽  
2021 ◽  
Author(s):  
Genevieve Westacott ◽  
Kirsten Vallmurr ◽  
Michael Schütz

AbstractData transfer has been forced to evolve as digital technologies are implemented throughout various aspects of the healthcare system. Despite the uniqueness of both the geography and the population of Queensland, information exchange and data communication has continued to follow this evolutionary trend. There have been a number of different health reforms designed to integrate digital innovations and allow critical data and information to be shared with the appropriate health professionals when necessary. Strict healthcare legislation has been navigated and to provide newly upgraded technologies and processes while maintaining privacy, confidentiality and security standards. A large portion of the digital revolution has been the implementation of the national run project, the My Health Record and the state run project, the Integrated Electronic Medical Record. Both are platforms that allow secure information exchange allowing patients to have improved quality of care. To maintain the steady progress, both the state and federal governments have developed strategies and visions to help provide guidance and direct for ongoing and future digital projects. They also outline areas that require further advancements to ensure Queensland is delivering equitable, high quality healthcare.


1992 ◽  
Vol 70 (3) ◽  
pp. 642-650 ◽  
Author(s):  
Raymond Louis Tremblay

Reduction in the number of pollinator species per plant species is a mechanism that may lower the cost of pollen transfer. Using efficient pollinators may have an evolutionary significance. It is hypothesized that an evolutionary trend from many pollinators to few pollinators per plant species should be observable when species from ancestral versus recently derived monophyletic taxon are compared. Three different orchid phylogenetic sequences are used; two of the phylogenies show a reduction in the number of pollinator species per orchid species from the most ancestral to the most recently derived subfamilies. The third classification did not show this trend. It is thus possible to observe macroevolution of pollinator specialization of a monophyletic plant taxon. Key words: evolution, pollination, systematics, Orchidaceae, evolutionary ecology.


Clay Research ◽  
2020 ◽  
Vol 39 (2) ◽  
pp. 77-88
Author(s):  
Ranjan Paul ◽  
Karunakaran Karthikeyan ◽  
Duraisamy Vasu ◽  
Sonalika Sahoo ◽  
Pramod Tiwary ◽  
...  
Keyword(s):  

2021 ◽  
pp. 72-77
Author(s):  
A.V. Verkhoturov ◽  
◽  
A.A. Obukhov

Analyzed is one of the most comprehensive modern approaches to the problem of the existence of evolution of human society as such and of specific human communities, i.e. “General Theory of Historical Development” by American historian and sociologist Stephen Sanderson. While agreeing, in general, with its main ideas, we believe that it is important to note that the issue of existence of individual communities demonstrating devolution (regression to an earlier historical state), stagnation or degeneration at certain historical stages is practically ignored in the framework of the theory under consideration. This creates its vulnerability in the face of specific empirical data, indicating a deviation from the evolutionary trend. We believe that overcoming this theoretical difficulty is possible in the process of comprehending the theory of S. Sanderson in the context of ideas of the world-system approach of Immanuel Wallerstein. We want to show that examples of devolution, stagnation and degeneration of societies do not deny general progressive evolutionary tendencies, characteristic for the world-system as a whole, but only indicate the transition of a particular society to a lower level within the world-system (from the core to the semi-periphery, or from the semi-periphery to the periphery).


Zootaxa ◽  
2011 ◽  
Vol 2825 (1) ◽  
pp. 1 ◽  
Author(s):  
MICHEL ROUX ◽  
PHILIP LAMBERT

Two new species of deep-sea stalked crinoids belonging to the family Hyocrinidae were collected in the northeastern Pacific. The descriptions contain detailed information on character variations and ontogeny. The five specimens of Gephyrocrinus messingi n. sp. lived at depths ranging from 1,777 m to 2,110 m off British Columbia and California. This new species is the first record of the genus Gephyrocrinus in the Pacific Ocean, which was previously known from only a single species, G. grimaldii, from the northeastern Atlantic at the same depth range. The two species illustrate opposing phenotypes within the same genus. Fifty-eight specimens of the second new species, Ptilocrinus clarki n. sp., were dredged off British Columbia close to the type-locality of P. pinnatus, the type species of the genus Ptilocrinus, but at shallower depths ranging from 1,178 to 1,986 m. This exceptional collection provides significant data on intraspecific variation in the main morphological characters, especially arm pattern. The ontogeny of stalk articulations and the main traits of adoral plate differentiation are described in detail. A complementary investigation on P. pinnatus was conducted using specimens collected by the “Albatross” expedition at a depth of 2,906 m. Despite similarities in external morphology, tegmen and cover plates, the two ptilocrinid species display significant differences in pinnule architecture, aboral cup and stalk articulations. From comparison with Gephyrocrinus messingi n. sp. and Ptilocrinus clarki n. sp., G. grimaldii and P. pinnatus are interpreted as the result of heterochronic development by paedomorphy after ecological or geographic isolation. Pinnule architecture in the two new species suggests first steps in an evolutionary trend toward a rigid box which protects gonad inflation in the proximal part of the pinnule. These new data on Ptilocrinus and Gephyrocrinus create problems in the current taxonomy of the family Hyocrinidae. The main derived characters, especially in pinnule and arm pattern, are used to propose new hypotheses for hyocrinid phylogeny.


Author(s):  
Javier Hernández Pacheco

Resumen: Después de revisar las tesis fundamentales de un radical monismo materialista, este trabajo presenta, con una cierta simpatía, la visión alternativa de un no menos radical panpsiquismo, con raíces en la arcaica tradición hylozoista griega y más recientemente rei­vindicado por el romanticismo europeo. Dejando aparte una solución dualista, el autor vuelve la vista a Aristóteles para proponer una concepción dinámica, donde un monismo pneumático constituye el término final de una evolución en la que el mismo ente consiste en la continua superación de la materialidad inercial. Palabras clave: Naturaleza, creación, evolución. Abstract: After reviewing the ground tenets of a radical materialist monism, this paper presents, with a certain sympathy, the alternative view of a not less radical panpsychism, with roots in the archaic Greek hylozoist tradition and more recently vindicated by the European Romantic. Letting aside a dualist solution, the author looks back to Aristotle to propose a dynamic conception, where a pneumatic monism constitutes the final term of an evolutionary trend, in which Being itself consists in the continuous overcoming of in­ertial materiality. Key words: nature, creation, evolution


mSystems ◽  
2020 ◽  
Vol 5 (6) ◽  
pp. e01234-20
Author(s):  
Kaichao Chen ◽  
Chen Yang ◽  
Ning Dong ◽  
Miaomiao Xie ◽  
Lianwei Ye ◽  
...  

ABSTRACTThe incidence of ciprofloxacin resistance in Salmonella has increased dramatically in the past decade. To track the evolutionary trend of ciprofloxacin resistance-encoding genetic elements during this period, we surveyed the prevalence of Salmonella in food products in Shenzhen, China, during the period of 2012 to 2017 and performed whole-genome sequencing and genetic analysis of 566 ciprofloxacin-resistant clinical Salmonella strains collected during this survey. We observed that target gene mutations have become much less common, with single gyrA mutation currently detectable in Salmonella enterica serovar Typhimurium only. Multiple plasmid-mediated quinolone resistance (PMQR) genes located in the chromosome and plasmids are now frequently detectable in ciprofloxacin-resistant Salmonella strains of various serotypes. Among them, the qnrS1 gene was often harbored by multiple plasmids, with p10k-like plasmids being the most dominant. Importantly, p10k-like plasmids initially were not conjugative but became transmissible with the help of a helper plasmid. Ciprofloxacin resistance due to combined effect of carriage of the qnrS1 gene and other resistance mechanisms is common. In S. Typhimurium, carriage of qnrS1 is often associated with a single gyrA mutation; in other serotypes, combination of qnrS1 and other PMQR genes located in the chromosomal fragment or plasmid is observed. Another major mechanism of ciprofloxacin resistance, mainly observable in S. Derby, involves a chromosomal fragment harboring the qnrS2–aac(6′)lb-cr–oqxAB elements. Intriguingly, this chromosomal fragment, flanked by IS26, could form a circular intermediate and became transferrable. To conclude, the increase in the incidence of various PMQR mobile genetic elements and their interactions with other resistance mechanism contribute to a sharp increase in the prevalence of ciprofloxacin-resistant clinical Salmonella strains in recent years.IMPORTANCE Resistance of nontyphoidal Salmonella to fluoroquinolones such as ciprofloxacin is known to be mediated by target mutations. This study surveyed the prevalence of Salmonella strains recovered from 2,989 food products in Shenzhen, China, during the period 2012 to 2017 and characterized the genetic features of several PMQR gene-bearing plasmids and ciprofloxacin resistance-encoding DNA fragments. The emergence of such genetic elements has caused a shift in the genetic location of ciprofloxacin resistance determinants from the chromosomal mutations to various mobile genetic elements. The distribution of these PMQR plasmids showed that they exhibited high serotype specificity, except for the p10k-like plasmids, which can be widely detected and efficiently transmitted among Salmonella strains of various serotypes by fusing to a new conjugative helper plasmid. The sharp increase in the prevalence of ciprofloxacin resistance in recent years may cause a predisposition to the emergence of multidrug-resistant Salmonella strains and pose huge challenges to public health and infection control efforts.


2020 ◽  
Author(s):  
Jing Li ◽  
Meiqi Lv ◽  
Lei Du ◽  
A Yunga ◽  
Shijie Hao ◽  
...  

AbstractThe monocot family Melanthiaceae with varying genome sizes in a range of 230-fold is an ideal model to study the genome size fluctuation in plants. Its family member Paris genus demonstrates an evolutionary trend of bearing huge genomes characterized by an average c-value of 49.22 pg. Here, we report a 70.18 Gb genome assembly out of the 82.55 Gb genome of Paris polyphylla var. yunnanensis (PPY), which represents the biggest sequenced genome to date. We annotate 69.53% repetitive sequences in this genome and 62.50% of which are long-terminal repeat (LTR) transposable elements. Further evolution analysis indicates that the giant genome likely results from the joint effect of common and species-specific expansion of different LTR superfamilies, which might contribute to the environment adaptation after speciation. Moreover, we identify the candidate pathway genes for the biogenesis of polyphyllins, the PPY-specific medicinal saponins, by complementary approaches including genome mining, comprehensive analysis of 31 next-generation RNA-seq data and 55.23 Gb single-molecule circular consensus sequencing (CCS) RNA-seq reads, and correlation of the transcriptome and phytochemical data of five different tissues at four growth stages. This study not only provides significant insights into plant genome size evolution, but also paves the way for the following polyphyllin synthetic biology.


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