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A set of 11 abstracts and short papers (extended abstracts) of presentations given at a meeting organized by the NFSR Working Group, "Micropaléontologie végétale et Palynologie (MVP)", held on May 24, 2006 at the University of Liège, Belgium. These contributions are available only in English or in French. 1- Some considerations on Devonian miospore taxonomy. 2- A classification of spores by support vectors based on an analysis of their ornament spatial distribution – An application to Emsian miospores from Saudi Arabia. 3- Palynology of Baudour Clays Formation (Mons Basin, Belgium): correlation within the "stratotypic" Wealden. 4- Observations on Wealden fossilised wood from the Mons Basin (Belgium) and their palaeoclimatic implications – preliminary results. 5- Advances in Ediacaran biostratigraphy in Australia. 6- Patterns of diversification in early eukaryotes. 7- Strud: old quarry, new discoveries. Preliminary report. 8- PalyWeb: A palynomorph database project on the web. 9- Palynological and geochemical data in peat sediments alongside an old (Roman or Merovingian) paved road in the Hautes-Fagnes. 10- Chitinozoans of the lower Llanvirn Huy and the middle Caradoc Sart-Bernard formations (Middle to Upper Ordovician): implications for the stratigraphy of the Condroz Inlier (Belgium). 11- Middle Devonian (Givetian) megaspores from Belgium (Ronquières) and Libya (A1-69 borehole).

Summary: Manual curation of bacterial cell detections in microscopy images remains a time-consuming and laborious task. This work offers a comprehensive, step-by-step tutorial on training a support vector machine to autonomously distinguish between good and bad cell detections. Jupyter notebooks are included to perform feature extraction, labeling, and training of the machine learning model. This method can readily be incorporated into profiling pipelines aimed at extracting a multitude of features across large collections of individual cells, strains, and species.For complete details on the use and execution of this protocol, please refer to Govers et al.1 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

A set of 14 abstracts and short papers (extended abstracts) of presentations given at a meeting organized by the NFSR Working Group, "Micropaléontologie végétale et Palynologie (MVP)", held on May 11, 2005 at the University of Liège, Belgium.

This extended abstract describes well-preserved palynomorph assemblages recovered from Devonian strata in five shallow boreholes in the northern part of Saudi Arabia. These fully cored holes overlap stratigraphically to form a 1,640 ft composite section spanning the upper Tawil, Jauf and lower Jubah formations. Only the Jauf and lower Jubah, represented by 188 samples taken over a 1,300 ft stratigraphic interval, are addressed here as the sandy Tawil lithologies are unsuitable for palynological analysis. The 900 feet of alternating of siliciclastic and carbonate units, that together comprise the five members of the Jauf Formation, were sampled comprehensively. However, the Jubah Formation, like the Tawil Formation, is mostly sandstone and is productive palynologically at only two levels separated by a 300 ft barren interval. The age of the sampled succession is assessed using index species from the established Euramerican Devonian palynozonations of Richardson & McGregor (1986) and Streel et alii (1987), and is shown to span the late Early and Middle Devonian.

Summary: Although ethanol is a class I carcinogen and is linked to more than 700,000 cancer incidences, a clear understanding of the molecular mechanisms underlying ethanol-related carcinogenesis is still lacking. Further understanding of ethanol-related cell damage can contribute to reducing or treating alcohol-related cancers. Here, we investigated the effects of both short- and long-term exposure of human laryngeal epithelial cells to different ethanol concentrations. RNA sequencing shows that ethanol altered gene expression patterns in a time- and concentration-dependent way, affecting genes involved in ribosome biogenesis, cytoskeleton remodeling, Wnt signaling, and transmembrane ion transport. Additionally, ethanol induced a slower cell proliferation, a delayed cell cycle progression, and replication fork stalling. In addition, ethanol exposure resulted in morphological changes, which could be associated with membrane stress. Taken together, our data yields a comprehensive view of molecular changes associated with ethanol stress in epithelial cells of the upper aerodigestive tract.

Introduction: Cardiotoxicity is one of the leading causes of compound attrition during drug development. Most in vitro screening platforms aim at detecting acute cardio-electrophysiological changes and drug-induced chronic functional alterations are often not studied in the early stage of drug development. Therefore, we developed an assay using human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) that evaluates both drug-induced acute and delayed electrophysiological and cytotoxic effects of reference compounds with clinically known cardiac outcomes.Methods: hiPSC-CMs were seeded in 48-well multielectrode array (MEA) plates and were treated with four doses of reference compounds (covering and exceeding clinical free plasma peak concentrations -fCmax values) and MEA recordings were conducted for 4 days. Functional-electrophysiological (field-potentials) and viability (impedance) parameters were recorded with a MEA machine.Results: To assess this platform, we tested tyrosine-kinase inhibitors with high-cardiac risk profile (sunitinib, vandetanib and nilotinib) and low-cardiac risk (erlotinib), as well as known classic cardiac toxic drugs (doxorubicin and BMS-986094), ion-channel trafficking inhibitors (pentamidine, probucol and arsenic trioxide) and compounds without known clinical cardiotoxicity (amoxicillin, cetirizine, captopril and aspirin). By evaluating the effects of these compounds on MEA parameters, the assay was mostly able to recapitulate different drug-induced cardiotoxicities, represented by a prolongation of the field potential, changes in beating rate and presence of arrhythmic events in acute (

This paper describes dispersed cryptospores and trilete spores from tropical, temperate and cool climate belts within Přídolí and compares them with the land plant megafossil record. The palynology of earlier intervals in the Silurian are also reviewed. A common feature of the cryptospore and trilete spore records is that their number is surprisingly lowest in the tropical climatic belt and much higher in the temperate and especially in the cool latitude, and the highest number of cryptospore taxa occurring only in one belt is found in the cool belt while the highest number of trilete spore taxa that occurred only in one belt is recorded in the temperate belt. In general, based on the dispersed spore record, we can estimate that the plant assemblages of the tropical belt were dominated by rhyniophytes; trimerophytes probably prevailed over rhyniophytes in the temperate belt, and rhyniophytes again dominated within the cool belt.

Lycopsids are a minor component of current terrestrial herbaceous floras. However, lycopsid fossil diversity shows a great diversity and disparity including heterosporous woody plants, e.g. the giant isoetaleans that populated the extensive Pennsylvanian wetlands. The earliest known isoetaleans come from late Devonian localities from China. Here, we describe Lilingostrobus chaloneri gen. et sp. nov., a new isoetalean lycopsid from the Upper Devonian (Famennian) Xikuangshan Formation of China (Hunan Province, South China), which adds to the already impressive diversity of the Devonian lycopsids from China. Lilingostrobus shows an unusual combination of characters. This new plant is pseudoherbaceous, with a possible tufted habit, and consists of narrow axes with rare isotomies. The stem includes small quantities of secondary xylem. Each fertile axis bears one terminal strobilus comprising sporophylls ending in a very long upturned lamina. Microspores and putative megaspores have been found, but whether the plant has mono- or bisporangiate strobili is unknown. Importantly, our cladistic analysis identifies Lilingostrobus as a direct precursor of Isoetales, which provides new insights into the early evolution of lycopsids.

The Lower Devonian Posongchong Formation (Wenshan, Yunnan Province, southwestern China) consists of a series of continental deposits with an outstanding plant megafossil diversity. More than 20 years ago, this formation was interpreted as 'Siegenian' (∼Pragian) in age based on palynology. However, such interpretation needs further evidence because of the known differences between the dispersed spore assemblages from South China and Euramerica/northwestern Gondwana. Here, we present new dispersed spore assemblages recently recovered from the Posongchong Formation. The isolated spore diversity is highly diverse, with 18 genera and 32 species. The recognised taxa include, among others, Ambitisporites avitus , Aneurospora conica , Aneurospora posongchongensis sp. nov., Aneurospora xujiachongensis , Apiculiretusispora plicata , Archaeozonotriletes chulus , Concentricosisporites agradabilis , Dibolisporites echinaceus , Emphanisporites rotatus , Gneudnaspora divellomedia , Latosporites ovalis , Retusotriletes triangulatus , Tetrahedraletes medinensis and Verrucosporites polygonalis , with Aneurospora and Retusotriletes being the most abundant forms. The known Posongchong palynoflora (previous spore data included) suggests that the Posongchong Formation assemblages can be correlated with the Pragian interval of the polygonalis–wetteldorfensis Oppel Zone (PoW). This age determination is supported by the presence of index species of PoW, such as Verrucosporites polygonalis , Dictyotriletes subgranifer and Camarozonotriletes parvus (sensu Steemans, 1989), the latter being known only from the Pragian of Belgium and Germany. Recent advances in the study of the marine faunas in the overlying sequences also indicate a Pragian age for the Posongchong Formation. This new investigation of the Posongchong palynoflora highlights differences of abundance at species level between the Gondwanan–Laurussian floras during the Early Devonian. [ABSTRACT FROM AUTHOR]

The QSIM-801 well from Central Saudi Arabia contains beds transitional between the Sajir Member of the Saq Formation and the Hanadir Member of the Qasim Formation. Core samples from these beds yielded rich assemblages of well-preserved palynomorphs of low thermal maturity. They are dominated by marine forms (acritarchs, chitinozoans and scolecodonts) but also include relatively abundant and diverse terrestrial forms (cryptospores and dispersed phytodebris), especially in samples from the upper part of the Sajir Member. The cryptospore assemblage is taxonomically consistent with other Middle Ordovician assemblages previously reported from Saudi Arabia, and is concordant with the late Dapingian to early Darriwillian (Llanvirn) age of the Sajir-Hanadir transitional beds, as suggested by palynological evidence (i.e., presence of Siphonochitina formosa and Linochitina pissotensis chitinozoan zones in the basal Hanadir). It includes a variety of monads and permanent dyads and tetrads, which are often characterized by well-developed surface ornamentation such as microgranulation, as well as, in some instances, by thick walls displaying distinct layering. [ABSTRACT FROM AUTHOR]

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Core samples from the QSIM-801 water well, drilled in central Saudi Arabia, cover a 93-foot interval spanning the transition between the Sajir Member of the Saq Formation, that consists mainly of sandstones of tidal sand flat environments, and the Hanadir Member of the Qasim Formation, characterized by argillaceous graptolitic mudstones, corresponding to a tidal delta front. The samples contain abundant, exceptionally well-preserved and diverse palynomorphs, which include cryptospores, acritarchs and chitinozoans, other problematic organic-walled microfossils as well as other organic particles such as cuticle-like fragments. The studied interval is biostratigraphically well constrained by the presence of chitinozoans of the formosa and pissotensis Zones of late-early to late Darriwilian age (Middle Ordovician) in the uppermost Saq Formation and Hanadir Member. The biostratigraphic age of the Sajir Member considered to span the Dapingian–Darriwilian boundary, is re-discussed based on the results herein. The uppermost part of the Sajir Member yielded the ichnofossil, Phycodes fusiforme . Acritarch assemblages from the Sajir Member of the Saq Formation are poorly diversified and dominated by sphaeromorphs. More diverse assemblages of acritarchs, associated with enigmatic forms, occur in the Hanadir Member of the Qasim Formation. The contact between the two formations and the transition between the palynomorph assemblages are sharp, suggesting a stratigraphic hiatus. A quantitative analysis allows us to discuss the paleoenvironmental changes and possibly climatic changes associated with an hypothesis of ice house conditions during this period. Among the diagnostic acritarch taxa observed are Frankea breviuscula, F. longiuscula , Baltisphaeridium ternatum , Dasydorus cirritus , Dicrodiacrodium ancoriforme, Poikilofusa ciliaris, Pterospermopsis colbathii and Uncinisphaera fusticula. These are associated with other typical forms known to range across the Lower–Middle Ordovician boundary, such as Aremoricanium rigaudae , Aureotesta clathrata , Barakella fortunata , B. rara, Baltisphaeridium klabavense, Glaucotesta latiramosa and Striatotheca spp. Galeate and peteinoid acritarchs are also well represented, as well as tiny forms of ultraplanctonic size. Three new species of acritarchs are proposed: Frankea longiuscula var . darriwilense var. nov, Micrhystridium regulum sp. nov, and Tyrannus proteus sp. nov. Repeated occurrences throughout the section of cryptospores, problematic microfossils such as organic filaments, cuticle-like tissues, striated and pigmented leiospheres frequently in clusters, are interpreted to reflect recurrent terrestrial and freshwater inputs in the depositional environment. Single-specimen, high-resolution analyses using Confocal Laser Scanning Microscopy on the enigmatic form Tyrannus proteus sp. nov. show fluorescence emission spectra and microstructural properties significantly different from those of typical marine acritarchs from the same levels. [ABSTRACT FROM AUTHOR]