Desmotheca (Orthotrichaceae) : Gondwanan fragmentation and the origin of a Southeast Asian genus

Desmotheca Lindberg was proposed in 1872 as a replacement name for the illegitimate Cryptocarpon Dozy & Molk. (1844) and Cryptocarpus Dozy & Molk. (1846). Seven names have been placed in these genera, from which two species appear to be taxonomically valid. Desmotheca apiculata (Dozy & Molk.) Card. occurs from New Caledonia and New Guinea west to Indonesia and the Andaman Islands, north to Burma, Thailand, Vietnam and Mindanao in the Philippines, while D. brachiata (Hook. & Wils.) Vitt comb. nova is restricted to the island of Luzon in the Philippines. The evolution and dispersal of this genus can be related to the northward movement of Gondwanan island blocks during the Cretaceous

Corytophanes cristatus

Number of Pages: 6Integrative BiologyGeological Science

Comparing voiced and voiceless geminates in Sienese Italian: what role does preaspiration play?

This paper compares the acoustic phonetic appearance of voiced & voiceless geminate stops in Sienese Italian. In our spontaneous speech data voiceless geminate stops are frequently preaspirated, which is an extremely rare phenomenon cross-linguistically. Preaspiration of voiceless stops has been associated in other languages with devoicing of voiced stops. We compare the acoustic appearance & duration of voiceless /VC:/ sequences (with & without preaspiration) with voiced /VC:/ sequences in our language. Results indicate that long voiced stops in Sienese Italian are often partially devoiced – a phenomenon that has not been reported previously for any variety of Italian. We suggest that preaspiration & devoicing are likely related, & attempt to provide an articulatory explanation as to why they occur

Iguana delicatissima

Number of Pages: 14Integrative BiologyGeological Science

The Interactive Effects of Multiple Stressors on Lithobates catesbeianus and Anaxyrus americanus

Amphibian populations worldwide have experienced dramatic declines, and many species have already become locally, regionally, or globally extirpated with thousands more being threatened with extinction. These declines have occurred more rapidly in amphibians than any other group of vertebrates, which is especially concerning to scientists because amphibians serve as indicator species of overall environmental health. Major causes for amphibian declines are discussed in Chapter 1 and include: habitat modification and destruction, commercial over-exploitation, introduced species, environmental contaminants, global climate change, and infectious diseases. Chapter 2 discusses the major research aspects of the thesis by examining the interactive effects of multiple stressors on two species of larval amphibians. The study investigated the individual and combined effects of a major environmental contaminant (Glyphosate, commercial Roundup ®), increased temperatures, and predatory cues on survival, growth, and development of tadpoles from two species (Lithobates catesbeianus and Anaxyrus americanus). Glyphosate reduced tadpole survival in both amphibian species and becomes more toxic to tadpoles as temperature increases. Increased temperature reduced survivorship over time in both species; however, survivorship decreased only when temperature interacted with glyphosate. Increased temperature also caused a decrease in growth in L. catesbeianus and an increase in growth and development in A. americanus. Accelerated growth and development caused by temperature may ameliorate the adverse effects of glyphosate by reducing larval period and increasing size at metamorphosis. Glyphosate caused significant anatomical shape variation in L. catebeianus, while increased temperature caused significant anatomical shape variation in A. americanus. The shape variations caused by the different stressors may lead to further developmental and behavioral abnormalities. Predatory cues had no effect on A. americanus survival, and only decreased growth and development at intermediate glyphosate concentrations and temperatures; therefore, the effects of temperature and glyphosate concentration may have been enhanced in the presence of predatory cues. The study highlighted the importance of examining the interactions between multiple stressors on amphibian declines. Chapter 3 focuses on potential solutions for global amphibian declines. Conservation efforts such as educational outreach, effective land management and water quality regulation guidelines, captive breeding programs, and several others are discussed

Immune complexes, innate immunity, and NETosis in ChAdOx1 vaccine-induced thrombocytopenia

Aims - We recently reported five cases of vaccine-induced immune thrombotic thrombocytopenia (VITT) 7–10 days after receiving the first dose of the ChAdOx1 nCoV-19 adenoviral vector vaccine against corona virus disease 2019 (COVID-19). We aimed to investigate the pathogenic immunological responses operating in these patients. Methods and results - We assessed circulating inflammatory markers by immune assays and immune cell phenotyping by flow cytometry analyses and performed immunoprecipitation with anti-platelet factor (PF)4 antibody in plasma samples followed by mass spectrometry from all five patients. A thrombus was retrieved from the sinus sagittal superior of one patient and analysed by immunohistochemistry and flow cytometry. Precipitated immune complexes revealed multiple innate immune pathway triggers for platelet and leucocyte activation. Plasma contained increased levels of innate immune response cytokines and markers of systemic inflammation, extensive degranulation of neutrophils, and tissue and endothelial damage. Blood analyses showed activation of neutrophils and increased levels of circulating H3Cit, dsDNA, and myeloperoxidase–DNA complex. The thrombus had extensive infiltration of neutrophils, formation of neutrophil extracellular traps (NETs), and IgG deposits. Conclusions - The results show that anti-PF4/polyanion IgG-mediated thrombus formation in VITT patients is accompanied by a massive innate immune activation and particularly the fulminant activation of neutrophils including NETosis. These results provide novel data on the immune response in this rare adenoviral vector-induced VITT

Effect of permafrost thaw on CO2 and CH4 exchange in a western Alaska peatland chronosequence

Permafrost soils store over half of global soil carbon (C), and northern frozen peatlands store about 10% of global permafrost C. With thaw, inundation of high latitude lowland peatlands typically increases the surface-atmosphere flux of methane (CH4), a potent greenhouse gas. To examine the effects of lowland permafrost thaw over millennial timescales, we measured carbon dioxide (CO2) and CH4 exchange along sites that constitute a ~1000 yr thaw chronosequence of thermokarst collapse bogs and adjacent fen locations at Innoko Flats Wildlife Refuge in western Alaska. Peak CH4 exchange in July (123 ± 71 mg CH4–C m−2 d−1) was observed in features that have been thawed for 30 to 70 (\u3c100) yr, where soils were warmer than at more recently thawed sites (14 to 21 yr; emitting 1.37 ± 0.67 mg CH4–C m−2 d−1 in July) and had shallower water tables than at older sites (200 to 1400 yr; emitting 6.55 ± 2.23 mg CH4–C m−2 d−1 in July). Carbon lost via CH4 efflux during the growing season at these intermediate age sites was 8% of uptake by net ecosystem exchange. Our results provide evidence that CH4 emissions following lowland permafrost thaw are enhanced over decadal time scales, but limited over millennia. Over larger spatial scales, adjacent fen systems may contribute sustained CH4 emission, CO2 uptake, and DOC export. We argue that over timescales of decades to centuries, thaw features in high-latitude lowland peatlands, particularly those developed on poorly drained mineral substrates, are a key locus of elevated CH4 emission to the atmosphere that must be considered for a complete understanding of high latitude CH4 dynamics

Font Letter: April 25, 1951

https://griffinshare.fontbonne.edu/font-letter/1066/thumbnail.jp

Phenology and mortality of embryos in a Colombian population of Nymphargus grandisonae (Anura: Centrolenidae)

Fenologia e mortalidade de embriões em uma população colombiana de Nymphargus grandisonae (Anura: Centrolenidae). Estudos de fenologia e história natural dos anuros fornecem informações úteis para sua conservação. Isso é particularmente importante nos cenários atuais de doenças emergentes, altas taxas de desmatamento e mudanças climáticas. Monitoramos a época de reprodução da perereca-de-vidro Nymphargus grandisonae (Centrolenidae) e sua relação com a precipitação e a temperatura ambiental durante quatro anos em uma população localizada nos Andes Centrais da Colômbia, América do Sul. Além disso, registramos as causas de mortalidade nas desovas dessa espécie. Quantificamos a infestação por larvas de moscas e seus efeitos na sobrevivência dos embriões. Descobrimos que a atividade reprodutiva de N. grandisonae (número de machos vocalizando) foi sazonal e ocorreu nos meses de maior precipitação. A principal causa de mortalidade embrionária nas desovas esteve associada à infestação por uma mosca do gênero c.f. Cladochaeta (Drosophilidae). A sobrevivência de embriões em desovas infestadas foi significativamente menor do que naquelas não infestadas pelas larvas da mosca. Nossos achados fornecem dados básicos para o monitoramento da dinâmica populacional de anuros na região Andina usando a perereca-de-vidro N. grandisonae como modelo de estudo.Phenology and mortality of embryos in a Colombian population of Nymphargus grandisonae (Anura: Centrolenidae). Studies of phenology and natural history of anurans provide information useful for its conservation. This is particularly important in current scenarios of emergent diseases, high rates of deforestation, and climate change. We recorded the timing of breeding of the Glass Frog Nymphargus grandisonae and its relationship to precipitation and environmental temperature for four years in a population located in the Central Andes of Colombia, South America. In addition, we recorded the causes of mortality in egg clutches of this species. We quantified infestation by fly larvae and its impact on the survival of embryos. We found that the reproductive activity of N. grandisonae (number of males calling) was seasonal and occurred in months with highest precipitation. The main cause of embryo mortality in clutches was associated with the infestation by a spittlebug fly of the genus c.f. Cladochaeta (Drosophilidae). The survival of embryos in infested clutches was significantly lower than in those clutches not infested by fly larvae. Our results provide baseline data for the monitoring of anuran population dynamics in the Andean region using the glass frog N. grandisonae as a model system