93 research outputs found
Complete mitochondrial genomes of the freshwater mussels Amblema plicata (Say, 1817), Pleurobema oviforme (Conrad, 1834), and Popenaias popeii (Lea, 1857) (Bivalvia: Unionidae: Ambleminae)
Freshwater mussels are a critically imperiled group of mollusks that play key ecological roles and provide important services to humans. The Ambleminae is the only subfamily of these mussels, endemic to North America. Complete mitogenomes have only been sequenced for two of five tribes of the subfamily. Pleurobema oviforme, Amblema plicata, and Popenaias popeii each belong to tribes Pleurobemini, Amblemini, and Popenaidini, respectively, and have not had published mitogenomes. Thus, this study aims to present the complete mitogenomes for these species, to provide a phylogeny of the Ambleminae and confirm the gene arrangements with representation from each of its tribes. The newly sequenced mitogenomes range from 15,852 to 15,993 nucleotides, are composed of 13 PCGs, 22 tRNAs, and two rRNAs and all share the same (UF1) gene order.This work was supported by Portuguese Foundation for Science and
Technology (FCT) [grant number ConBioMics/BI-Lic/2019-037 (JTT), grant
number SFRH/BD/137935/2018 (AGS)]; COMPETE 2020, Portugal 2020
and the European Union through the ERDF, and by Portuguese
Foundation for Science and Technology (FCT) through national funds
[UID/Multi/04423/2019] under project ConBiomics: the missing approach
for the Conservation of Bivalves Project, and [project number NORTE-01-
0145-FEDER-030286]. Fieldwork in Texas was funded by the U.S. Fish and Wildlife Service, and Texas Parks and Wildlife Department (TPWD) as a Joint Traditional Section 6 Project 407348.info:eu-repo/semantics/publishedVersio
Mesozoic mitogenome rearrangements and freshwater mussel (Bivalvia: Unionoidea) macroevolution
© 2019, The Author(s), under exclusive licence to The Genetics Society. Using a new fossil-calibrated mitogenome-based approach, we identified macroevolutionary shifts in mitochondrial gene order among the freshwater mussels (Unionoidea). We show that the early Mesozoic divergence of the two Unionoidea clades, Margaritiferidae and Unionidae, was accompanied by a synchronous split in the gene arrangement in the female mitogenome (i.e., gene orders MF1 and UF1). Our results suggest that this macroevolutionary jump was completed within a relatively short time interval (95% HPD 201–226 Ma) that coincided with the Triassic–Jurassic mass extinction. Both gene orders have persisted within these clades for ~200 Ma. The monophyly of the so-called “problematic” Gonideinae taxa was supported by all the inferred phylogenies in this study using, for the first time, the M- and F-type mitogenomes either singly or combined. Within Gonideinae, two additional splits in the gene order (UF1 to UF2, UF2 to UF3) occurred in the Mesozoic and have persisted for ~150 and ~100 Ma, respectively. Finally, the mitogenomic results suggest ancient connections between freshwater basins of East Asia and Europe near the Cretaceous–Paleogene boundary, probably via a continuous paleo-river system or along the Tethys coastal line, which are well supported by at least three independent but almost synchronous divergence events
Expansion and systematics redefinition of the most threatened freshwater mussel family, the Margaritiferidae.
Two Unionida (freshwater mussel) families are present in the Northern Hemisphere; the Margaritiferidae, representing the most threatened of unionid families, and the Unionidae, which include several genera of unresolved taxonomic placement. The recent reassignment of the poorly studied Lamprotula rochechouartii from the Unionidae to the Margaritiferidae motivated a new search for other potential species of margaritiferids from members of Gibbosula and Lamprotula. Based on molecular and morphological analyses conducted on newly collected specimens from Vietnam, we here assign Gibbosula crassa to the Margaritiferidae. Additionally, we reanalyzed all diagnostic characteristics of the Margaritiferidae and examined museum specimens of Lamprotula and Gibbosula. As a result, two additional species are also moved to the Margaritiferidae, i.e. Gibbosula confragosa and Gibbosula polysticta. We performed a robust five marker phylogeny with all available margaritiferid species and discuss the taxonomy within the family. The present phylogeny reveals the division of Margaritiferidae into four ancient clades with distinct morphological, biogeographical and ecological characteristics that justify the division of the Margaritiferidae into two subfamilies (Gibbosulinae and Margaritiferinae) and four genera (Gibbosula, Cumberlandia, Margaritifera, and Pseudunio). The systematics of the Margaritiferidae family is re-defined as well as their distribution, potential origin and main biogeographic patterns
The male and female complete mitochondrial genomes of the threatened freshwater pearl mussel Margaritifera margaritifera (Linnaeus, 1758) (Bivalvia: Margaritiferidae)
The complete mitogenomes of one (M-)ale (North America), one Hermaphroditic (Europe), and two (F-)emale (North America and Europe) individuals of the freshwater pearl mussel Margaritifera margaritifera were sequenced. The M-type and F-type (Female and Hermaphroditic) mitogenomes have 17,421 and 16,122 nucleotides, respectively. All with the same content: 13 protein-coding genes, 22 transfer RNA, two ribosomal RNA genes, and one sex-related ORF. The M-type is highly divergent (37.6% uncorrected p-distance) from the F-type mitogenomes. North American and European F-type mitogenomes exhibit low genetic divergence (68 nt substitutions), and the Female and Hermaphroditic European mitogenomes are almost identical, and matching sex-related ORFs.This work was supported by Portuguese Foundation for Science and Technology (FCT) [grant number SFRH/BD/115728/2016 (MLL), grant number SFRH/BD/137935/2018 (AGS)]; Russian Foundation for Basic Research [grant number 18-34-20033 (IVV)]; Dawson Fellowship at St. Catharine's College, Cambridge (DCA); Life Margal Ulla [number LIFE09 NAT/ES/000514 (RA and PO)]; COMPETE 2020, Portugal 2020 and the European Union through the ERDF, and by Portuguese Foundation for Science and Technology (FCT) through national funds [UID/Multi/04423/2019] under project ConBiomics: the missing approach for the Conservation of freshwater Bivalves Project, and [project number NORTE-01-0145-FEDER-030286]; Federal Agency for Scientific Organizations under Grants [grant number 0409-2015-0143 (INB and IVV)
Ninety-day complication rate based on 532 Latarjet procedures in Dutch hospitals with different operation volumes
Background: In this study, we aimed to provide insight into the 90-day complication rates following the Latarjet procedure. Data from 2015 were collected from multiple hospitals in the Netherlands, with different volumes of Latarjet procedures. Our second aim was to examine which patient and surgical factors were associated with complications.Methods: We conducted a retrospective chart review of 13 hospitals between 2015 and 2022. Data regarding complications within 90 days of Latarjet procedures were extracted. The effect of sex, age, body mass index (BMI), smoking, previous shoulder operations, fixation material, hospital volume, screw size, and operation time on the complication rate was assessed by multivariable logistic regression analysis.Results: Of the 532 included patients, 58 (10.9%) had complications. The most common complications were material failure (n = 19, 3.6%) and nerve injury (n = 13, 2.4%). The risk of complications was lower for male patients than for female patients (odds ratio, 0.40; 95% confidence interval, 0.21-0.77; P = .006). Age, BMI, smoking, previous shoulder operations, type of fixation material, hospital volume, screw size, and operation time were not associated with complications.Conclusion: The 90-day complication rate after the Latarjet procedure was 10.9% and was higher in female patients than in male patients. Age, BMI, smoking, previous shoulder operations, type of fixation material, hospital volume, screw size, and operation time did not affect complication rates. We advise setting up a national registry to prevent under-reporting of complications.</p
Mitogenomic phylogeny and fossil-calibrated mutation rates for all F- and M-type mtDNA genes of the largest freshwater mussel family, the Unionidae (Bivalvia)
The Unionidae represent an excellent model taxon for unravelling the drivers of freshwater diversity, but, phylogeographic studies on Southeast Asian taxa are hampered by lack of a comprehensive phylogeny and mutation rates for this fauna. We present complete female- (F) and male-type (M) mitogenomes of four genera of the Southeast Asian clade Contradentini+Rectidentini. We calculate substitution rates for the mitogenome, the 13 protein-coding genes, the two ribosomal units and three commonly used fragments (co1, nd1 and 16S) of both F- and M-mtDNA, based on a fossil-calibrated, mitogenomic phylogeny of the Unionidae. Phylogenetic analyses, including an M+F concatenated dataset, consistently recovers a monophyletic Gonideinae. Subfamily-level topology is congruent with that of a previous nuclear genomic study and with patterns in mitochondrial gene order, suggesting Unionidae F-type 2 as a synapomorphy of the Gonideinae. Our phylogeny indicates that the clades Contradentini+Rectidentini and Lamprotulini+Pseudodontini+Gonideini split in the early Cretaceous (~125 Mya), and that the crown group of Contradentini+Rectidentini originated in the late Cretaceous (~79 Mya). Most gonideine tribes originated during the early Palaeogene. Substitution rates were comparable to those previously published for F-type co1 and 16S for certain Unionidae and Margaritiferidae species (pairs)
Identifying and Prioritizing Greater Sage-Grouse Nesting and Brood-Rearing Habitat for Conservation in Human-Modified Landscapes
BACKGROUND: Balancing animal conservation and human use of the landscape is an ongoing scientific and practical challenge throughout the world. We investigated reproductive success in female greater sage-grouse (Centrocercus urophasianus) relative to seasonal patterns of resource selection, with the larger goal of developing a spatially-explicit framework for managing human activity and sage-grouse conservation at the landscape level. METHODOLOGY/PRINCIPAL FINDINGS: We integrated field-observation, Global Positioning Systems telemetry, and statistical modeling to quantify the spatial pattern of occurrence and risk during nesting and brood-rearing. We linked occurrence and risk models to provide spatially-explicit indices of habitat-performance relationships. As part of the analysis, we offer novel biological information on resource selection during egg-laying, incubation, and night. The spatial pattern of occurrence during all reproductive phases was driven largely by selection or avoidance of terrain features and vegetation, with little variation explained by anthropogenic features. Specifically, sage-grouse consistently avoided rough terrain, selected for moderate shrub cover at the patch level (within 90 m(2)), and selected for mesic habitat in mid and late brood-rearing phases. In contrast, risk of nest and brood failure was structured by proximity to anthropogenic features including natural gas wells and human-created mesic areas, as well as vegetation features such as shrub cover. CONCLUSIONS/SIGNIFICANCE: Risk in this and perhaps other human-modified landscapes is a top-down (i.e., human-mediated) process that would most effectively be minimized by developing a better understanding of specific mechanisms (e.g., predator subsidization) driving observed patterns, and using habitat-performance indices such as those developed herein for spatially-explicit guidance of conservation intervention. Working under the hypothesis that industrial activity structures risk by enhancing predator abundance or effectiveness, we offer specific recommendations for maintaining high-performance habitat and reducing low-performance habitat, particularly relative to the nesting phase, by managing key high-risk anthropogenic features such as industrial infrastructure and water developments
Technology-supported learning innovation in cultural contexts
Many reform initiatives adopt a reductionist, proceduralized approach to cultural change, assuming that deep changes can be realized by introducing new classroom activities, textbooks, and technological tools. This article elaborates a complex system perspective of learning culture: A learning culture as a complex system involves macro-level properties (e.g., epistemological beliefs, social values, power structures) and micro-level features (e.g., technology, classroom activities). Deep changes in macro-level properties cannot be reduced to any component. This complex system perspective is applied to examining technology-supported educational change in East Asia and analyzing how teachers sustain the knowledge building innovation in different contexts. Working with the macro-micro dynamics in a learning culture requires a principle-based approach to learning innovation that specifies macro-level changes using principle-based instead of procedure-based terms and engages teachers’ deep reflection and creative engagement at both the macro- and the micro-level
The conservation status of the world's freshwater molluscs
With the biodiversity crisis continuing unchecked, we need to establish levels and drivers of extinction risk, and reassessments over time, to effectively allocate conservation resources and track progress towards global conservation targets. Given that threat appears particularly high in freshwaters, we assessed the extinction risk of 1428 randomly selected freshwater molluscs using the IUCN Red List Categories and Criteria, as part of the Sampled Red List Index project. We show that close to one-third of species in our sample are estimated to be threatened with extinction, with highest levels of threat in the Nearctic, Palearctic and Australasia and among gastropods. Threat levels were higher in lotic than lentic systems. Pollution (chemical and physical) and the modification of natural systems (e.g. through damming and water abstraction) were the most frequently reported threats to freshwater molluscs, with some regional variation. Given that we found little spatial congruence between species richness patterns of freshwater molluscs and other freshwater taxa, apart from crayfish, new additional conservation priority areas emerged from our study. We discuss the implications of our findings for freshwater mollusc conservation, the adequacy of a sampled approach and important next steps to estimate trends in freshwater mollusc extinction risk over time
Variable responses of individual species to tropical forest degradation
The functional stability of ecosystems depends greatly on interspecific differences in responses to environmental perturbation. However, responses to perturbation are not necessarily invariant among populations of the same species, so intraspecific variation in responses might also contribute. Such inter-population response diversity has recently been shown to occur spatially across species ranges, but we lack estimates of the extent to which individual populations across an entire community might have perturbation responses that vary through time. We assess this using 524 taxa that have been repeatedly surveyed for the effects of tropical forest logging at a focal landscape in Sabah, Malaysia. Just 39 % of taxa – all with non-significant responses to forest degradation – had invariant responses. All other taxa (61 %) showed significantly different responses to the same forest degradation gradient across surveys, with 6 % of taxa responding to forest degradation in opposite directions across multiple surveys. Individual surveys had low power (< 80 %) to determine the correct direction of response to forest degradation for one-fifth of all taxa. Recurrent rounds of logging disturbance increased the prevalence of intra-population response diversity, while uncontrollable environmental variation and/or turnover of intraspecific phenotypes generated variable responses in at least 44 % of taxa. Our results show that the responses of individual species to local environmental perturbations are remarkably flexible, likely providing an unrealised boost to the stability of disturbed habitats such as logged tropical forests
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