Major Subdivisions Research Articles

Bringing together but staying apart: decisive differences in animal and fungal mitochondrial inner membrane fusion.

Mitochondria are dynamic and plastic, undergoing continuous fission and fusion and rearrangement of their bioenergetic sub-compartments called cristae. These fascinating processes are best understood in animal and fungal models, which are taxonomically grouped together in the expansive Opisthokonta supergroup. In opisthokonts, crista remodelling and inner membrane fusion are linked by dynamin-related proteins (DRPs). Animal Opa1 (optical atrophy 1) and fungal Mgm1 (mitochondrial genome maintenance 1) are tacitly considered orthologs because their similar mitochondria-shaping roles are mediated by seemingly shared biochemical properties, and due to their presence in the two major opisthokontan subdivisions, Holozoa and Holomycota, respectively. However, molecular phylogenetics challenges this notion, suggesting that Opa1 and Mgm1 likely had separate, albeit convergent, evolutionary paths. Herein, we illuminate disparities in proteolytic processing, structure, and interaction network that may have bestowed on Opa1 and Mgm1 distinct mechanisms of membrane remodelling. A key disparity is that, unlike Mgm1, Opa1 directly recruits the mitochondrial phospholipid cardiolipin to remodel membranes. The differences outlined herein between the two DRPs could have broader impacts on mitochondrial morphogenesis. Outer and inner membrane fusion are autonomous in animals, which may have freed Opa1 to repurpose its intrinsic activity to remodel cristae, thereby regulating the formation of respiratory chain supercomplexes. More significantly, Opa1-mediated crista remodelling has emerged as an integral part of cytochrome c-regulated apoptosis in vertebrates, and perhaps in the cenancestor of animals. By contrast, outer and inner membrane fusion are coupled in budding yeast. Consequently, Mgm1 membrane-fusion activity is inextricable from its role in the biogenesis of fungal lamellar cristae. These disparate mitochondrial DRPs ultimately may have contributed to the different modes of multicellularity that have evolved within Opisthokonta.

Science Fiction in the Anthropocene

This article catalogs major recent trends in ecological science fiction (sf), focused primarily on sf published after the completion of N.K. Jemisin's paradigm-setting Broken Earth trilogy in 2017. Major subdivisions in the genre include dystopian and antiutopian narratives about climate collapse, technocratic solutionism, reckoning with climate change as a colonial project, intergenerational conflict, and posthuman formulation. Noting that sf both as literary genre and as fan community encompasses a wide range of political perspectives ranging from reactionary hypercapitalism to utopian socialism, the article does not seek to advance any particular political position but rather seeks to name the major currents of political and ethical debate within sf in this moment of ecological crisis. The article concludes with a brief discussion of the way the sf genre, in reframing the present as the history of multiple possible futures, calls on us to act to shape that future toward human thriving.

TAF15 downregulation contributes to the benefits of physical training on dendritic spines and working memory in aged mice.

Moderate physical training has been shown to hinder age-related memory decline. While the benefits of physical training on hippocampal memory function are well-documented, little is known about its impact on working memory, which is linked to the prelimbic cortex (PrL), one major subdivision of the prefrontal cortex. Here, we examined the effects of physical training on spatial working memory in a well-established animal model of physical training, starting at 16 months of age and continuing for 5 months (running wheel 1 h/day and 5 days/week). This training strategy improved spatial working memory in aged mice (22-month-old), which was accompanied by an increased spine density and a lower TAF15 expression in the PrL. Specifically, physical training affected both thin and mushroom-type spines on PrL pyramidal cells, and prevented age-related loss of spines on selective segments of apical dendritic branches. Correlation analysis revealed that increased TAF15-expression was detrimental to the dendritic spines. However, physical training downregulated TAF15 expression in the PrL, preserving the dendritic spines on PrL pyramidal cells and improving working memory in trained aged mice. When TAF15 was overexpressed in the PrL via a viral approach, the benefits of physical training on the dendritic spines and working memory were abolished. These data suggest that physical training at a moderate pace might downregulate TAF15 expression in the PrL, which favors the dendritic spines on PrL pyramidal cells, thereby improving spatial working memory.

Bibliometric Analysis of Trends and Future Directions of Research and Development of Seed Orchards

Seed orchards are important seed resources for producing improved tree crops for future plantations, forest restoration, and forestry practices (i.e., gene conservation) and for transmitting current gene diversity to future generations. Seed orchards are a major sub-division in forest science. The establishment and management of a seed orchard involves many steps, from the selection of superior trees to the harvesting of a seed crop. Studying the trends and future directions of seed orchards using different analysis methods is critically important, especially to establish resistant forests via the production of climate-smart, biotic/abiotic-stress-resistant seedling materials. Published papers related to seed orchards should be analyzed to determine the current trends in this field and to contribute to its future directions. Bibliometric analysis has been used for different purposes in various scientific fields. However, it has not been performed for publications in seed orchards. This study was carried out to analyze the current trends of research on seed orchards and to determine the future directions of these orchards based on published papers. For these purposes, 1018 published papers were obtained from the Science Citation Index, Science Citation Index Expanded, and citation index databases of “Web of Science” using the keyword “seed orchard”. The papers were published between 1980 and 2022 and were subjected to bibliometric analysis based on the most prolific contributors, references, countries, and keywords. CiteSpace software 6.1 R6 was applied to visualize information about seed orchard research. The average number of citations per publication was 13.05, and the 4 H-Index of the publication set was 48. The most prolific contributors with the strongest citation bursts, the highest centrality, and the greatest numbers of published papers were from Canada, Sweden, South Korea, Finland, and Czech Republic, while Canada (186 published articles), the USA (140), and Sweden (115), together with China, Brazil, and Germany, were active countries, especially based on citations from recent years. The “keywords” of the papers were the core of the research. “Mating pattern”, “Swedish forestry”, “fertility variation”, “Hymenoscyphus fraxineus”, “threatened Pacific sandalwood”, “outbreeding depression”, “climate change”, “management”, and “growth”, together with others such as “genetic improvement” and “effective size”, were active study areas and keywords, based on results of the analysis. They also guided the literature search and inventory and classification of early studies and served as predictors for future studies. The results of this study are discussed based on the trends and future directions of the research and development of seed orchards.

A cortical locus for modulation of arousal states.

Fluctuations in global arousal are key determinants of spontaneous cortical activity and function. Several subcortical structures, including neuromodulator nuclei like the locus coeruleus (LC), are involved in the regulation of arousal. However, much less is known about the role of cortical circuits that provide top-down inputs to arousal-related subcortical structures. Here, we investigated the role of a major subdivision of the prefrontal cortex, the anterior cingulate cortex (ACC), in arousal modulation. Pupil size, facial movements, heart rate, and locomotion were used as non-invasive measures of arousal and behavioral state. We designed a closed loop optogenetic system based on machine vision and found that real time inhibition of ACC activity during pupil dilations suppresses ongoing arousal events. In contrast, inhibiting activity in a control cortical region had no effect on arousal. Fiber photometry recordings showed that ACC activity scales with the magnitude of spontaneously occurring pupil dilations/face movements independently of locomotion. Moreover, optogenetic ACC activation increases arousal independently of locomotion. In addition to modulating global arousal, ACC responses to salient sensory stimuli scaled with the size of evoked pupil dilations. Consistent with a role in sustaining saliency-linked arousal events, pupil responses to sensory stimuli were suppressed with ACC inactivation. Finally, our results comparing arousal-related ACC and norepinephrinergic LC neuron activity support a role for the LC in initiation of arousal events which are modulated in real time by the ACC. Collectively, our experiments identify the ACC as a key cortical site for sustaining momentary increases in arousal and provide the foundation for understanding cortical-subcortical dynamics underlying the modulation of arousal states.

The international political economy of Saudi Arabia: Sovereign fund and foreign policy

AbstractThis article develops a framework for attributing motivations to Sovereign Wealth Fund (SWF) investment by noting that there are two major subdivisions, those that argue that the investments are undertaken due to macroeconomic factors and those that argue there is a political element as well. The political literature is divided into three subcategories of domestic political considerations, geopolitical competition and economic diplomacy. The literature of the Public Investment Fund (PIF) does not include any discussion of economic diplomacy as a consideration, an omission this article seeks to rectify. Using a realist understanding of international political economy (IPE), the article explores the influence of elites, the nature of PIF investments in America, India, China and Russia, and collaboration with other SWFs on investment. The article concludes that economic diplomacy should be considered as one of a multitude of variables that determine how and where the PIF invests.

Advances in Limnogeology: The lake‐basin‐type model revisited 25 years after…anomalies, conundrums and upgrades

AbstractThe lake‐basin‐type model classified the stratigraphic record of ancient lake systems according to rates of potential accommodation relative to sediment + water supply. The model convolved all modes and paths of water supply (direct fall, surficial, subsurface) with amounts and types of sediment supply (clastic, biogenic, chemical) into a single basin‐filling volume term (sediment + water); its major strength was its widespread applicability. This was supported by subsequent investigations confirming the utility of this approach, but it also revealed some important limitations due to simplifications in the original model. The model has been expanded here to address all inland waters (lakes, ponds, wetlands, playas) as well as adding two major subdivisions of the sediment + water term: (1) water supply paths and (2) the volume of water supply relative to sediment supply. Water supply flow paths in the subsurface are subdivided into ‘throughflow’, ‘recharge’ and ‘discharge’. Each of these groundwater hydrology states can be defined quite precisely by the ratio of net outflow to inflow, from persistently open to consistently closed. These paths can be deciphered using stable carbonate and oxygen isotope composition of primary lacustrine limestones, detailed sedimentology, stratigraphy, palaeontology and mineralogy. Distinguishing water supply paths provides additional insights into playa systems and the occurrence and character of evaporites and carbonates. The volume ratio of water to sediment supply most directly influences the water depths of lakes, ponds and wetlands, which affect water body hydrodynamics and ecosystem behaviour as well as the details of stratal stacking and depositional sequences. It helps fine‐tune estimates of the distribution of sediment texture, bedding, composition and organic matter content. The aim of this contribution is to address questions about the fundamental types of inland water bodies and to explain the new lake‐basin subtypes and provide examples that illustrate their potential to enable higher‐resolution, robust analysis of inland water systems and their stratigraphic records.

A detailed 3D MRI brain atlas of the African lungfish Protopterus annectens

The study of the brain by magnetic resonance imaging (MRI) in evolutionary analyses is still in its incipient stage, however, it is particularly useful as it allows us to analyze detailed anatomical images and compare brains of rare or otherwise inaccessible species, evolutionarily contextualizing possible differences, while at the same time being non-invasive. A good example is the lungfishes, sarcopterygians that are the closest living relatives of tetrapods and thus have an interesting phylogenetic position in the evolutionary conquest of the terrestrial environment. In the present study, we have developed a three-dimensional representation of the brain of the lungfish Protopterus annectens together with a rostrocaudal anatomical atlas. This methodological approach provides a clear delineation of the major brain subdivisions of this model and allows to measure both brain and ventricular volumes. Our results confirm that lungfish show neuroanatomical patterns reminiscent of those of extant basal sarcopterygians, with an evaginated telencephalon, and distinctive characters like a small optic tectum. These and additional characters uncover lungfish as a remarkable model to understand the origins of tetrapod diversity, indicating that their brain may contain significant clues to the characters of the brain of ancestral tetrapods.

Novel insight into lepidopteran phylogenetics from the mitochondrial genome of the apple fruit moth of the family Argyresthiidae

BackgroundThe order Lepidoptera has an abundance of species, including both agriculturally beneficial and detrimental insects. Molecular data has been used to investigate the phylogenetic relationships of major subdivisions in Lepidoptera, which has enhanced our understanding of the evolutionary relationships at the family and superfamily levels. However, the phylogenetic placement of many superfamilies and/or families in this order is still unknown. In this study, we determine the systematic status of the family Argyresthiidae within Lepidoptera and explore its phylogenetic affinities and implications for the evolution of the order. We describe the first mitochondrial (mt) genome from a member of Argyresthiidae, the apple fruit moth Argyresthia conjugella. The insect is an important pest on apples in Fennoscandia, as it switches hosts when the main host fails to produce crops.ResultsThe mt genome of A. conjugella contains 16,044 bp and encodes all 37 genes commonly found in insect mt genomes, including 13 protein-coding genes (PCGs), two ribosomal RNAs, 22 transfer RNAs, and a large control region (1101 bp). The nucleotide composition was extremely AT-rich (82%). All detected PCGs (13) began with an ATN codon and terminated with a TAA stop codon, except the start codon in cox1 is ATT. All 22 tRNAs had cloverleaf secondary structures, except trnS1, where one of the dihydrouridine (DHU) arms is missing, reflecting potential differences in gene expression. When compared to the mt genomes of 507 other Lepidoptera representing 18 superfamilies and 42 families, phylogenomic analyses found that A. conjugella had the closest relationship with the Plutellidae family (Yponomeutoidea-super family). We also detected a sister relationship between Yponomeutoidea and the superfamily Tineidae.ConclusionsOur results underline the potential importance of mt genomes in comparative genomic analyses of Lepidoptera species and provide valuable evolutionary insight across the tree of Lepidoptera species.

A multifaceted architectural framework of the mouse claustrum complex.

Accurate anatomical characterizations are necessary to investigate neural circuitry on a fine scale, but for the rodent claustrum complex (CLCX), this has yet to be fully accomplished. The CLCX is generally considered to comprise two major subdivisions, the claustrum (CL) and the dorsal endopiriform nucleus (DEn), but regional boundaries to these areas are debated. To address this, we conducted a multifaceted analysis of fiber- and cytoarchitecture, genetic marker expression, and connectivity using mice of both sexes, to create a comprehensive guide for identifying and delineating borders to CLCX, including an online reference atlas. Our data indicated four distinct subregions within CLCX, subdividing both CL and DEn into two. Additionally, we conducted brain-wide tracing of inputs to CLCX using a transgenic mouse line. Immunohistochemical staining against myelin basic protein (MBP), parvalbumin (PV), and calbindin (CB) revealed intricate fiber-architectural patterns enabling precise delineations of CLCX and its subregions. Myelinated fibers were abundant dorsally in CL but absent ventrally, whereas PV expressing fibers occupied the entire CL. CB staining revealed a central gap within CL, also visible anterior to the striatum. The Nr2f2, Npsr1, and Cplx3 genes expressed specifically within different subregions of the CLCX, and Rprm helped delineate the CL-insular border. Furthermore, cells in CL projecting to the retrosplenial cortex were located within the myelin sparse area. By combining own experimental data with digitally available datasets of gene expression and input connectivity, we could demonstrate that the proposed delineation scheme allows anchoring of datasets from different origins to a common reference framework.

Morphometric study of sex differences and static variation in the skull of Indochinese ground squirrel, Menetes berdmorei (Rodentia: Sciuridae)

Sexual dimorphism, a common morphological phenomenon in rodents, has often been explained as the result of both sexual and natural selection. However, few studies have focused on detailed patterns of sexual dimorphism in squirrels. In this study, we investigated the patterns of sex differences and static variation in the skull of Indochinese ground squirrel (Menetes berdmorei) using linear morphometrics. A total of 24 adult skulls (15 males and 9 females) were measured, of which males showed slightly larger mean size in 19 measurements. Univariate analyses demonstrated significant differences between the sexes in few variables, while discriminant analysis indicated well distinctiveness in craniomandibular morphology. The coefficient of variation showed an inverse relationship with the mean values of skull traits. This trend might be caused by real biological phenomena, as previously reported in several studies. Although coefficient of variation tended to be larger in anterior part of the viscerocranium and smaller in posterior of the neurocranium, similar variability patterns were observed in most of the skull trails. These trends were also supported by the alternative index of the coefficient of variation and coefficients of bivariate allometry. Even though, existence of developmental factors is suggested by the patterns of variability, higher integration is denoted in major subdivisions of the skull. In conclusion, our results demonstrate a slight male-biased sexual size dimorphism in M. berdmorei. Besides, variability patterns might indicate higher morphological integration in major components of the skull.

Abelisauroidea (Theropoda, Dinosauria) from Africa: a review of the fossil record

The Continental African abelisauroid theropod dinosaur fossil record from the Jurassic-Cretaceous periods is becoming increasingly better understood, and offers great insight into the evolution and biogeography of this long-lived group of carnivores. Abelisauroidea is among the most familiar groups of theropod dinosaurs from Gondwana, with fossil records in South America, Australia, India and Africa, along with Europe. The objective of the present study is to review the fossil record of abelisauroids in continental Africa. Based on the literature and records from the online databases “The Paleobiology Database” and “The Theropod Database”, we review the distribution of these theropods in Africa and comment on their evolution. The African continent is a major region of importance when it comes to 26 Abelisauroidea fossil findings, including records of both major subdivisions of the clade: the Abelisauridae and Noasauridae families. The oldest Abelisauroidea fossil record found in Africa dates from the Late Jurassic, while the final records date from the end of the Cretaceous. This indicates that clade was the longest surviving lineage of the large theropods of Africa, and they filled a variety of ecological roles, including apex predators, at the end of the Cretaceous, when tyrannosaurids occupied similar niches in the northern continents.

Tubarial Salivary Gland – The New Member of Nasopharynx

Tubarial Salivary Gland – The New Member of Nasopharynx

Biological differences between FIM2 and FIM3 fimbriae of Bordetella pertussis: not just the serotype

IntroductionBordetella pertussis still circulates worldwide despite vaccination. Fimbriae are components of some acellular pertussis vaccines. Population fluctuations of B. pertussis fimbrial serotypes (FIM2 and FIM3) are observed, and fim3 alleles (fim3-1 [clade 1] and fim3-2 [clade 2]) mark a major phylogenetic subdivision of B. pertussis. ObjectivesTo compare microbiological characteristics and expressed protein profiles between fimbrial serotypes FIM2 and FIM3 and genomic clades. MethodsA total of 19 isolates were selected. Absolute protein abundance of the main virulence factors, autoagglutination and biofilm formation, bacterial survival in whole blood, induced blood cell cytokine secretion, and global proteome profiles were assessed. ResultsCompared to FIM3, FIM2 isolates produced more fimbriae, less cellular pertussis toxin subunit 1 and more biofilm, but auto-agglutinated less. FIM2 isolates had a lower survival rate in cord blood, but induced higher levels of IL-4, IL-8 and IL-1β secretion. Global proteome comparisons uncovered 15 differentially produced proteins between FIM2 and FIM3 isolates, involved in adhesion and metabolism of metals. FIM3 isolates of clade 2 produced more FIM3 and more biofilm compared to clade 1. ConclusionFIM serotype and fim3 clades are associated with proteomic and other biological differences, which may have implications on pathogenesis and epidemiological emergence.

Biogeographic inferences across spatial and evolutionary scales.

The field of biogeography unites landscape genetics and phylogeography under a common conceptual framework. Landscape genetics traditionally focuses on recent-time, population-based, spatial genetics processes at small geographical scales, while phylogeography typically investigates deep past, lineage- and species-based processes at large geographical scales. Here, we evaluate the link between landscape genetics and phylogeographical methods using the western fence lizard (Sceloporus occidentalis) as a model species. First, we conducted replicated landscape genetics studies across several geographical scales to investigate how population genetics inferences change depending on the spatial extent of the study area. Then, we carried out a phylogeographical study of population structure at two evolutionary scales informed by inferences derived from landscape genetics results to identify concordance and conflict between these sets of methods. We found significant concordance in landscape genetics processes at all but the largest geographical scale. Phylogeographical results indicate major clades are restricted to distinct river drainages or distinct hydrological regions. At a more recent timescale, we find minor clades are restricted to single river canyons in the majority of cases, while the remainder of river canyons include samples from at most two clades. Overall, the broad-scale pattern implicating stream and river valleys as key features linking populations in the landscape genetics results, and high degree of clade specificity within major topographic subdivisions in the phylogeographical results, is consistent. As landscape genetics and phylogeography share many of the same objectives, synthesizing theory, models and methods between these fields will help bring about a better understanding of ecological and evolutionary processes structuring genetic variation across space and time.

Molecular Diversity of Neuron Types in the Salamander Amygdala and Implications for Amygdalar Evolution

The amygdala is a complex brain structure in the vertebrate telencephalon, essential for regulating social behaviors, emotions, and (social) cognition. In contrast to the vast majority of neuron types described in the many nuclei of the mammalian amygdala, little is known about the neuronal diversity in non-mammals, making reconstruction of its evolution particularly difficult. Here, we characterize glutamatergic neuron types in the amygdala of the urodele amphibian Pleurodeles waltl. Our single-cell RNA sequencing data indicate the existence of at least ten distinct types and subtypes of glutamatergic neurons in the salamander amygdala. These neuron types are molecularly distinct from neurons in the ventral pallium (VP), suggesting that the pallial amygdala and the VP are two separate areas in the telencephalon. In situ hybridization for marker genes indicates that amygdalar glutamatergic neuron types are located in three major subdivisions: the lateral amygdala, the medial amygdala, and a newly defined area demarcated by high expression of the transcription factor Sim1. The gene expression profiles of these neuron types suggest similarities with specific neurons in the sauropsid and mammalian amygdala. In particular, we identify Sim1+ and Sim1+ Otp+ expressing neuron types, potentially homologous to the mammalian nucleus of the lateral olfactory tract (NLOT) and to hypothalamic-derived neurons of the medial amygdala, respectively. Taken together, our results reveal a surprising diversity of glutamatergic neuron types in the amygdala of salamanders, despite the anatomical simplicity of their brain. These results offer new insights on the cellular and anatomical complexity of the amygdala in tetrapod ancestors.

Ordovician biostratigraphy: index fossils, biozones and correlation

Abstract Two remarkable events in the history of life on the Earth occur during the Ordovician Period (486.9–443.1 Ma). The first is an exceptionally rapid and sustained radiation of marine life known as the ‘Great Ordovician Biodiversification Event’ (GOBE), and the second is a catastrophic Late Ordovician mass extinction (LOME). Understanding the duration, rate and magnitude of these events requires an increasingly precise global correlation framework. In this chapter we review the major subdivisions of the Ordovician System, their Global Stratotype Section and Points, and the chronostratigraphic levels that define their bases. We also present a detailed set of correlation charts that illustrate the relationships between most of the regional graptolite, conodont and chitinozoan successions across the world.

Potential petroleum prospects in the middle Benue trough, central Nigeria: Inferences from integrated applications of geological, geophysical and geochemical studies

The Middle Benue Trough (MBT) is the least well-known of the three major sub-divisions of the Benue Trough (BT) and therefore poorly understood geologically. This paper presents preliminary results of an integrated geological, aeromagnetic, gravity and geochemical studies carried out as a first step approach to petroleum exploration in the central portion (MBT) of the Benue Trough, Nigeria, so as to be able to; 1. Appraise the regional geologic setting of the MBT with a view to understanding the stratigraphy and its oil generation characteristics; 2. Determine the basin configuration and sediment thicknesses and; 3. identify and delineate “leads” or prospect areas for further detailed exploration that could lead to significant commercial discoveries of hydrocarbon in the MBT. Results have revealed the existence of petroleum systems in the MBT with the interbedded shales of the Bima and Yolde formations at the upper portions and the shales of the Asu River Group, Awe, Ezeaku and Agwu formations corresponding to the potential source rocks. The main local potential reservoir rocks are the Bima Sandstones and sandstones of the Yolde Formation coupled with the interbedded arkosic sandstones of the Awe and Keana Formations, while potential regional seals are the shales of Pindiga Formation and the arkosic sandstones overlying the shales of the Asu River Group and the basal shales of the Ezeaku formation and the upper shales horizon of the Agwu formation. Geophysical studies (Aeromagnetic/gravity survey) revealed the variability of the surface to Basement depths within the Middle Benue Trough ranging from 3 – 6 km with the deepest portions of up to 8.2 km towards the Northeastern portion of the MBT. The thick sediment piles coupled with the favorable petroleum systems, provide the conditions necessary for hydrocarbon generation, migration and accumulation. The prominent lineament structure is the NE-SW directional Keana anticline which extends along a strike for more than 100 Km from the south of Makurdi to Zurak in the northern portion. Trans tensional and trans compressional fault systems in the basin have given rise to sub-surface and extensive lineament structures systems which could either constitute major structural traps or pathways for fluid (hydrocarbon) flow. The analysis of a wide range of geochemical data from the MBT revealed TOC values ranging from 0.43 to 3.90wt% for shales/coaly shales and 14.78–79.10wt% for shaly coal/coal facies embedded in the Agwu formation with Tmax values corresponding to immature to mature stages of thermal maturation. Their petroleum potential in terms of HI values ranges from 14 to 267mgHC/gTOC in shale/coaly shale facies and 36–157mgHC/gTOC in shaly coal/coal facies, corresponding to the predominance of type III (gas-prone) in addition to type II (oil and gas-prone) organic matter suggestive of having both oil and gas generating potential. The recent discovery of significant quantity of oil (+gas) in the well Kolmani River-1 in the Gongola Sub-basin, is in strong support of its occurrence in the MBT. The paper has recommended selected prospect areas favorable for further detail hydrocarbon exploration.

Coastal barrier morphogenic categories in Mississippi Delta plain development

Coastal barriers are defined as shore-parallel, aggraded-prograded supratidal beach ridge sets and individual single ridge-landforms, composed of sand and/or gravel. Island, spit, and mainland barriers represent the three major topographic subdivisions. In terms of bathymetric and hydrographic characteristics, bottom sediment types and associated habitats, barriers separate the marine offshore from inshore facies. This definition is not uniformly accepted and applied in the literature. Barriers impose reduced salinities inshore, diminish storm impact and moderate inland inundation, protect critical habitats and may mark ancient longshore transport directions, shore and sea-level positions. A wide range of dimensions, topography, and other factors characterize mainland strandplains. Shoal aggradation appears to be the prime island-forming mechanism, followed by accretion around semi-consolidated, elevated cores. Smaller islands may also form by barrier spit fragmentation. Detachment of dune ridges from the mainland shore is an often cited but at best unlikely mode of island genesis. Review of the literature and remote-sensed images created new insights, utilized barrier definitions and genetic theories, as applied in the Mississippi Delta Complex. A three-stage concept, involving dune ridge or barrier spit-detachment by marine encroachment and landward shift of fragmented transgressive islands forms the basis of a recent invited Marine Geology research article. That model assumes spit-growth from delta headlands, followed by splintering into landward-migrating islands. Submerged, they become permanent shoals. For several reasons, this “island-cycle” hypothesis is questionable and a reassessment of the geomorphic and stratigraphic context of this delta coast is required.Contradicting the geomorphic setting of assumed Stage 1, key component of the cycle-model, evidence is lacking for subrecent delta lobes and erosional headland in spawning barrier islands. In addition, the delta headland-flanking islands reveal only progradational (regressive) development and in situ disintegration,. Transgressive landward migrations is known only from the Chandeleur chain's prehistory. Sand from decaying Terrebonne-Lafourche 6 Subdelta headland was the dominant source for the Caminada Strandplain and for the shoal /or island predecessor of Grand Isle. Wave refraction around an inferred Lafourche delta lobe (dated provisionally between ∼2900 - ∼ 2300 yrs. BP) and its decayed erosional headland remnant resulted in diametric reversal of littoral sand transport. An earlier proferred ∼750–300 yrs. BP Caminada Strandplain age range is now replaced by a loosely defined ∼2200- to- ∼800 yrs. BP value, based on ages of Grand Isle and reworked delta hinterland sediments incorporated into the Strandplain.

Northern Tosk Albanian

Albanian (endonym: Shqip; Glotto: alba1268) is an Indo-European language which has been suggested to form an independent branch of the Indo-European family since the middle of the nineteenth century (Bopp 1855, Pedersen 1897, Çabej 1976). Though the origin of the language has been debated, the prevailing opinion in the literature is that it is a descendant of Illyrian (Hetzer 1995). Albanian is currently spoken by around 6–7 million people (Rusakov 2017: 552; Curtis 2018: 1800), the majority of whom live in Albania and Kosovo, with others in Italy, Greece, North Macedonia and Montenegro. Figure 1 shows a map of the main Albanian-speaking areas of Europe, with major linguistic subdivisions according to Gjinari (1988) and Elsie & Gross (2009) marked by different colours and shades.