scholarly journals A phasianid bird from the Pleistocene of Tainan: the very first avian fossil from Taiwan

2021 ◽  
Author(s):  
Cheng-Hsiu Tsai ◽  
Gerald Mayr
Keyword(s):  
Fossil Birds ◽  
Phasianus Colchicus ◽  
Diagnostic Features ◽  
Physical Evidence ◽  
Evolutionary Origins ◽  
Geological Past ◽  
Fossil Bird ◽  
New Perspective ◽  
High Degree ◽  
Unambiguous Assignment

AbstractTaiwan accommodates more than 600 avian species, including about 30 endemic ones. As yet, however, no fossil birds have been scientifically documented from Taiwan, so that the evolutionary origins of this diversified avifauna remain elusive. Here we report on the very first fossil bird from Taiwan. This Pleistocene specimen, a distal end of the left tarsometatarsus, shows diagnostic features of the galliform Phasianidae, including an asymmetric plantar articular facet trochlea metatarsi III. Our discovery of a Pleistocene phasianid from Taiwan opens a new perspective on studies of the evolution of the avifauna in Taiwan because the fossil shows that careful search for fossils in suitable localities has the potential of recovering avian remains. In general, East Asia has an extremely poor avian fossil record, especially if terrestrial birds are concerned, which impedes well-founded evolutionary scenarios concerning the arrival of certain groups in the area. The Phasianidae exhibit a high degree of endemism in Taiwan, and the new fossil presents the first physical evidence for the presence of phasianids on the island, some 400,000–800,000 years ago. The specimen belongs to a species the size of the three larger phasianids occurring in Taiwan today (Syrmaticus mikado, Lophura swinhoii, and Phasianus colchicus). Still, an unambiguous assignment to either of these species is not possible due to the incomplete nature of the left tarsometatarsus. Because the former two species are endemic to Taiwan, the fossil has the potential to yield the first data on their existence in the geological past of Taiwan if future finds allow identification on species-level.

scholarly journals Rat mesangial cells and matrix metalloproteinase inhibitor: inhibition of 72-kD type IV collagenase (MMP-2) and of cell proliferation.

1997 ◽  
Vol 8 (3) ◽  
pp. 395-405 ◽  
Author(s):  
K Steinmann-Niggli ◽  
M Lukes ◽  
H P Marti
Keyword(s):  
Mesangial Cells ◽  
Inflammatory Diseases ◽  
Constitutive Expression ◽  
Matrix Metalloproteinase Inhibitor ◽  
Type Iv Collagenase ◽  
Type Iv ◽  
Synthetic Inhibitor ◽  
Inflammatory Phenotype ◽  
New Perspective ◽  
High Degree

The synthetic inhibitor of matrix metalloproteinases (MMP) Ro 31-9790, a hydroxamic-acid derivative, was investigated for its effect on rat mesangial cells (MC) in culture. For these studies, proliferating MC with a high degree of constitutive expression of a MMP, the 72-kD Type IV collagenase (gelatinase A, MMP-2), were chosen, because they reflect aspects of an inflammatory phenotype that may occur during certain forms of glomerular inflammatory diseases. Ro 31-9790 inhibited activity of the rat MC MMP-2 in a concentration-dependent and competitive fashion, as analyzed by quantitative densitometry and by a continuously recording fluorescent assay. Furthermore, Ro 31-9790 inhibited the proliferation rate of cultured rat MC in a concentration-dependent and at least partially reversible manner without affecting cell viability. It was concluded that the application of synthetic MMP inhibitors may offer a new perspective for the therapy of mesangial cell-derived forms of glomerulonephritis.

scholarly journals Demystifying Social Bots: On the Intelligence of Automated Social Media Actors

2020 ◽  
Vol 6 (3) ◽  
pp. 205630512093926 ◽  
Author(s):  
Dennis Assenmacher ◽  
Lena Clever ◽  
Lena Frischlich ◽  
Thorsten Quandt ◽  
Heike Trautmann ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Social Media ◽  
Public Opinion ◽  
Research Effort ◽  
Online Media ◽  
Social Media Platforms ◽  
New Perspective ◽  
High Degree ◽  
Supportive Nature ◽  
Shed Light

Recently, social bots, (semi-) automatized accounts in social media, gained global attention in the context of public opinion manipulation. Dystopian scenarios like the malicious amplification of topics, the spreading of disinformation, and the manipulation of elections through “opinion machines” created headlines around the globe. As a consequence, much research effort has been put into the classification and detection of social bots. Yet, it is still unclear how easy an average online media user can purchase social bots, which platforms they target, where they originate from, and how sophisticated these bots are. This work provides a much needed new perspective on these questions. By providing insights into the markets of social bots in the clearnet and darknet as well as an exhaustive analysis of freely available software tools for automation during the last decade, we shed light on the availability and capabilities of automated profiles in social media platforms. Our results confirm the increasing importance of social bot technology but also uncover an as yet unknown discrepancy of theoretical and practically achieved artificial intelligence in social bots: while literature reports on a high degree of intelligence for chat bots and assumes the same for social bots, the observed degree of intelligence in social bot implementations is limited. In fact, the overwhelming majority of available services and software are of supportive nature and merely provide modules of automation instead of fully fledged “intelligent” social bots.

scholarly journals A Christian Emperor between Pagan Gods

2021 ◽  
pp. 1-44
Author(s):  
Ketty Iannantuono
Keyword(s):  
Roman Empire ◽  
Late Antiquity ◽  
Late Antique ◽  
Political Dissent ◽  
The Media ◽  
New Form ◽  
New Perspective ◽  
Ancient Monuments ◽  
High Degree

Abstract In recent years, images of rage against monuments have filled the media. Unmistakably expressing a high degree of tension in societies, these forms of hostility against heritage have been diversely interpreted, prompting passionate expressions of support as well as fierce criticism. Contesting public memorials, however, is not a new form of socio-political dissent. During Late Antiquity, for example, a new sensibility towards ancient monuments emerged in the vast territories that were once part of the Roman Empire. In this article, the late-antique fate of the so-called ‘temple of Hadrian’ at Ephesus is analysed as a case-study. The aim is to gain a better understanding of the approaches adopted to accommodate traditional monumental landscapes in the changed late-antique socio-political context. This analysis offers a new perspective on ancient and contemporary phenomena of contestations of monuments.

scholarly journals Multi-region proteome analysis quantifies spatial heterogeneity of prostate tissue biomarkers

2018 ◽  
Vol 1 (2) ◽  
pp. e201800042 ◽  
Author(s):  
Tiannan Guo ◽  
Li Li ◽  
Qing Zhong ◽  
Niels J Rupp ◽  
Konstantina Charmpi ◽  
...  
Keyword(s):  
Biomarker Discovery ◽  
Specific Antigen ◽  
Proteome Analysis ◽  
Tissue Microarrays ◽  
Protein Biomarker ◽  
Pressure Cycling ◽  
Pressure Cycling Technology ◽  
New Perspective ◽  
High Degree ◽  
Independent Cohort

It remains unclear to what extent tumor heterogeneity impacts on protein biomarker discovery. Here, we quantified proteome intra-tissue heterogeneity (ITH) based on a multi-region analysis of prostate tissues using pressure cycling technology and Sequential Windowed Acquisition of all THeoretical fragment ion mass spectrometry. We quantified 6,873 proteins and analyzed the ITH of 3,700 proteins. The level of ITH varied depending on proteins and tissue types. Benign tissues exhibited more complex ITH patterns than malignant tissues. Spatial variability of 10 prostate biomarkers was validated by immunohistochemistry in an independent cohort (n = 83) using tissue microarrays. Prostate-specific antigen was preferentially variable in benign prostatic hyperplasia, whereas growth/differentiation factor 15 substantially varied in prostate adenocarcinomas. Furthermore, we found that DNA repair pathways exhibited a high degree of variability in tumorous tissues, which may contribute to the genetic heterogeneity of tumors. This study conceptually adds a new perspective to protein biomarker discovery: it suggests that recent technological progress should be exploited to quantify and account for spatial proteome variation to complement biomarker identification and utilization.

Cretaceous fossil birds from Hornby Island (British Columbia)

2005 ◽  
Vol 42 (12) ◽  
pp. 2097-2101 ◽  
Author(s):  
Kurt Morrison ◽  
Gareth J Dyke ◽  
Luis M Chiappe
Keyword(s):  
British Columbia ◽  
Marine Sediments ◽  
West Coast ◽  
Marine Ecosystems ◽  
Fossil Birds ◽  
The West ◽  
Strait Of Georgia ◽  
Fossil Bird

We present the first records of Mesozoic fossil birds to be described from British Columbia. New fossil avians from the Campanian Northumberland Formation on Hornby Island (Strait of Georgia) add to the known distributions of two groups of fossil birds during the latter stage of the Mesozoic. New specimens referred to the clades Ornithurae and Enantiornithes demonstrate the presence of a diverse marine avifauna in Canadian Pacific marine sediments prior to the Cretaceous–Tertiary (K–T) boundary. These new fossil bird remains from coastal rocks on the west coast of British Columbia lend further support to suggestions that ocean-going birds were important constituents of marine ecosystems in the terminal stages of the Mesozoic.

scholarly journals Obituary notices of fellows deceased

1926 ◽  
Vol 100 (705) ◽  
Keyword(s):  
New Zealand ◽  
British Museum ◽  
Fossil Birds ◽  
Limb Bones ◽  
Vertebrate Palaeontology ◽  
General Catalogue ◽  
Fossil Bird ◽  
London Clay ◽  
The University ◽  
Geological Research

Charles William Andrews was born at Hampstead in 1866, and died in London on May 25, 1924, having spent his active official life in the service of the British Museum. He was a graduate in both arts and science of the University of London, and began his career as a schoolmaster. His main interest, however, was in biological and geological research, and in 1892 he was fortunate in being the successful candidate in a competitive examination for an assistantship in the Department of Geology in the British Museum (Natural History). Here he soon began to add original investigation to his curatorial duties, and he eventually became one of the foremost exponents of vertebrate palæontology. Dr. Andrews at first paid much attention to the fossil birds, of which a useful general catalogue had just been published by Lydekker. He made himself well acquainted with the osteology of birds, and so was adequately equipped for dealing with the large collections of bones of extinct birds which were then being discovered in the surface deposits of lands in the southern hemisphere. In his earliest paper, published in the Geological Magazine in 1894, he described some limb-bones of the largest known running bird from Madagascar, which he named Aepyornis titan . In subsequent years he made several important contributions to our knowledge of both the Aepyornithes and the fossil carinate birds of Madagascar. At the same time he studied the extinct birds of New Zealand, and a large collection of fossil bird-bones from the Chatham Islands which Lord Rothschild had obtained for the Tring Museum. He pointed out especially that the occurrence of closely related flightless rails in Mauritius, the Chatham Islands, and New Zealand, did not necessitate a former con­nection between those widely separated lands. The rails might have become flightless independently in the different restricted habitats, and an almost flightless rail, Nesolimnas , among the fossils from the Chatham Islands seemed to show that in this form the wings were actually being reduced on the spot. Dr. Andrews also published important new observations on the remains of the Stereornithes and other remarkable extinct birds, discovered by Ameghino in Patagonia, which were received by the British Museum in 1896. To the end he retained an interest in all fossil remains of birds, and his descriptions of an ancestral tropic-bird, Prophaethon , from the Eocene London Clay of Sheppey, and a sternum of the largest known flying bird from an Eocene formation in Nigeria, are especially noteworthy.

scholarly journals First dinosaur from the Isle of Eigg (Valtos Sandstone Formation, Middle Jurassic), Scotland

2020 ◽  
pp. 1-16
Author(s):  
Elsa PANCIROLI ◽  
Gregory F. FUNSTON ◽  
Femke HOLWERDA ◽  
Susannah C. R. MAIDMENT ◽  
Davide FOFFA ◽  
...  
Keyword(s):  
Middle Jurassic ◽  
Diagnostic Features ◽  
Cross Sectional ◽  
Limb Bones ◽  
Fossil Material ◽  
Sandstone Formation ◽  
Dinosaur Fossil ◽  
High Degree ◽  
Body Fossil ◽  
Isle Of Skye

ABSTRACT Dinosaur body fossil material is rare in Scotland, previously known almost exclusively from the Great Estuarine Group on the Isle of Skye. We report the first unequivocal dinosaur fossil from the Isle of Eigg, belonging to a Bathonian (Middle Jurassic) taxon of uncertain affinity. The limb bone NMS G.2020.10.1 is incomplete, but through a combination of anatomical comparison and osteohistology, we determine it most likely represents a stegosaur fibula. The overall proportions and cross-sectional geometry are similar to the fibulae of thyreophorans. Examination of the bone microstructure reveals a high degree of remodelling and randomly distributed longitudinal canals in the remaining primary cortical bone. This contrasts with the histological signal expected of theropod or sauropod limb bones, but is consistent with previous studies of thyreophorans, specifically stegosaurs. Previous dinosaur material from Skye and broadly contemporaneous sites in England belongs to this group, including Loricatosaurus and Sarcolestes and a number of indeterminate stegosaur specimens. Theropods such as Megalosaurus and sauropods such as Cetiosaurus are also known from these localities. Although we find strong evidence for a stegosaur affinity, diagnostic features are not observed on NMS G.2020.10.1, preventing us from referring it to any known genera. The presence of this large-bodied stegosaur on Eigg adds a significant new datapoint for dinosaur distribution in the Middle Jurassic of Scotland.

Fossil Birds

The Geologist ◽  
1863 ◽  
Vol 6 (11) ◽  
pp. 415-424
Keyword(s):  
Future Study ◽  
British Museum ◽  
The State ◽  
Fossil Birds ◽  
The Future ◽  
Fossil Bird ◽  
The Subject ◽  
Do So

The wonderful remains of the Archæopteryx, recently acquired for the British Museum, have naturally drawn attention to a muchneglected department of palæontology; and it will therefore not only be interesting, but useful also to the advance of science, to pass under review, at the present time, the state of our knowledge of the former existence of birds during past geological ages. The early authors, for the most part, speak not of fossil bird-remains properly so called, but in reality of mere incrustations by “petrifying springs,” of the fanciful tracery of dendritic markings, or the imagined resemblances of oddly-formed stones. Thus Albertus Magnus, in his book ‘De Mineralibus,’ printed in 1495, describes a fossil nest, with eggs, on the branch of a tree. This might or might not be a true fossil, but our recent discoveries of fossil birds and reptiles' eggs, and the knowledge we have now of delicate objects truly fossilized, such as insects, fruits, flowers, and feathers, renders it possible that some of the old records of such may have had a foundation of truth, and gives a probability that some at least may be brought within the capacity of belief as actual facts.With this view, we shall quote from the old authors all the passages known to us, commenting on them as occasion may require; and in thus working up the bibliography of fossil ornithology and arranging the whole of our knowledge of the subject, as far as we have the power to do so, we shall be able to separate facts from fictions, and give a solid basis for further investigations in the future study of ornithological palæontology.

scholarly journals Transcriptomic analysis of diplomonad parasites reveals a trans-spliced intron in a helicase gene in Giardia

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e2861 ◽  
Author(s):  
Scott William Roy
Keyword(s):  
Dna Sequences ◽  
Molecular Mechanisms ◽  
Transcriptomic Data ◽  
Coding Regions ◽  
Evolutionary Origins ◽  
Helicase Gene ◽  
Trans Splicing ◽  
High Degree ◽  
Future Work

Background The mechanisms by which DNA sequences are expressed is the central preoccupation of molecular genetics. Recently, ourselves and others reported that in the diplomonad protist Giardia lamblia, the coding regions of several mRNAs are produced by ligation of independent RNA species expressed from distinct genomic loci. Such trans-splicing of introns was found to affect nearly as many genes in this organism as does classical cis-splicing of introns. These findings raised questions about the incidence of intron trans-splicing both across the G. lambliatranscriptome and across diplomonad diversity in general, however a dearth of transcriptomic data at the time prohibited systematic study of these questions. Methods I leverage newly available transcriptomic data from G. lamblia and the related diplomonad Spironucleus salmonicidato search for trans-spliced introns. My computational pipeline recovers all four previously reported trans-spliced introns in G. lamblia, suggesting good sensitivity. Results Scrutiny of thousands of potential cases revealed only a single additional trans-spliced intron in G. lamblia, in the p68 helicase gene, and no cases in S. salmonicida. The p68 intron differs from the previously reported trans-spliced introns in its high degree of streamlining: the core features of G. lamblia trans-spliced introns are closely packed together, revealing striking economy in the implementation of a seemingly inherently uneconomical molecular mechanism. Discussion These results serve to circumscribe the role of trans-splicing in diplomonads both in terms of the number of genes effected and taxonomically. Future work should focus on the molecular mechanisms, evolutionary origins and phenotypic implications of this intriguing phenomenon.

The Avifauna of the Rio Branco, an Amazonian evolutionary and ecological hotspot in peril

2019 ◽  
Vol 30 (1) ◽  
pp. 21-39 ◽  
Author(s):  
LUCIANO N. NAKA ◽  
THIAGO ORSI LARANJEIRAS ◽  
GISIANE RODRIGUES LIMA ◽  
ALICE C. PLASKIEVICZ ◽  
DANIELE MARIZ ◽  
...  
Keyword(s):  
Bird Species ◽  
Flood Pulse ◽  
Sandy Beaches ◽  
Physical Evidence ◽  
Habitat Specialisation ◽  
River Islands ◽  
Ecological Features ◽  
Hydroelectric Dam ◽  
Gallery Forests ◽  
High Degree

SummaryThe Rio Branco is a river with unique biogeographic and ecological features, threatened by the Brazilian Government’s plan to build a major hydroelectric dam and associated hydroway along its course. The river crosses one of Amazonia’s largest rainfall gradients and a major geomorphological boundary along a savanna/forest ecotone, marked by the Bem Querer rapids. Above the rapids, the upper Rio Branco runs through the Boa Vista sedimentary formation and crosses the crystalline rocks of the Guiana Shield, and its margins are flanked by gallery forests. Downriver, it runs through a low-lying sedimentary basin, with Amazonian floodplain forests along its margins. Here, we present the results of ∼ 15 years of ornithological research on the Branco and its major tributaries, providing baseline data and evaluating potential threats to the riverine avifauna. Our surveys included opportunistic observations and standardized surveys along the entire length of the river in 16 systematically distributed localities. We catalogued 439 bird species, 87% of which are documented by physical evidence (specimens, recordings, photographs). Forty-six percent are restricted to single habitats, suggesting a high degree of habitat specialisation. A third of the species are widely distributed along the river, whereas 45% are restricted to either the upper or the lower Rio Branco, including 40 and 30 Indicator Species, respectively. Twenty-five species are threatened at global or national levels, including two ‘Critically Endangered’, nine ‘Vulnerable’, and 14 ‘Near Threatened’. We present a list of 50 bird species that are candidates for monitoring studies. Threats to the avifauna from dam construction include permanent flooding above the dam, eliminating gallery forests, river islands, and sandy beaches, and the disruption of the flood pulse along the river, affecting river island and floodplain forest specialists, many of which are globally threatened with extinction. If built, the Bem Querer dam will wipe out the ecotone region and affect dramatically the river’s avifauna.

Sign in / Sign up

Export Citation Format

Share Document