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The oldest known bat skeletons and their implications for Eocene chiropteran diversification
Get PDFThe Fossil Lake deposits of the Green River Formation of Wyoming, a remarkable early Eocene Lagerstätte (51.98 ±0.35 Ma), have produced nearly 30 bat fossils over the last 50 years. However, diversity has thus far been limited to only two bat species. Here, we describe a new species of Icaronycteris based on two articulated skeletons discovered in the American Fossil Quarry northwest of Kemmerer, Wyoming. The relative stratigraphic position of these fossils indicates that they are the oldest bat skeletons recovered to date anywhere in the world. Phylogenetic analysis of Eocene fossil bats and living taxa places the new species within the family Icaronycteridae as sister to Icaronycteris index, and additionally indicates that the two Green River archaic bat families (Icaronycteridae and Onychonycteridae) form a clade distinct from known Old World lineages of archaic bats. Our analyses found no evidence that Icaronycteris? menui (France) nor I. sigei (India) belong to this clade; accordingly, we therefore remove them from Icaronycteridae. Taken in sum, our results indicate that Green River bats represent a separate chiropteran radiation of basal bats, and provide additional support for the hypothesis of a rapid radiation of bats on multiple continents during the early Eocene
Integrated de novo gene prediction and peptide assembly of metagenomic sequencing data
Get PDFMetagenomics is the study of all genomic content contained in given microbial communities. Metagenomic functional analysis aims to quantify protein families and reconstruct metabolic pathways from the metagenome. It plays a central role in understanding the interaction between the microbial community and its host or environment. De novo functional analysis, which allows the discovery of novel protein families, remains challenging for high-complexity communities. There are currently three main approaches for recovering novel genes or proteins: de novo nucleotide assembly, gene calling and peptide assembly. Unfortunately, their information dependency has been overlooked, and each has been formulated as an independent problem. In this work, we develop a sophisticated workflow called integrated Metagenomic Protein Predictor (iMPP), which leverages the information dependencies for better de novo functional analysis. iMPP contains three novel modules: a hybrid assembly graph generation module, a graph-based gene calling module, and a peptide assembly-based refinement module. iMPP significantly improved the existing gene calling sensitivity on unassembled metagenomic reads, achieving a 92–97% recall rate at a high precision level (>85%). iMPP further allowed for more sensitive and accurate peptide assembly, recovering more reference proteins and delivering more hypothetical protein sequences. The high performance of iMPP can provide a more comprehensive and unbiased view of the microbial communities under investigation. iMPP is freely available from https://github.com/Sirisha-t/iMPP
In situ Raman spectroscopy study of silver particle size effects on unpromoted Ag/α-Al2O3 during ethylene epoxidation with molecular oxygen
Get PDFIn situ Raman spectroscopy and parallel fixed bed reactor studies were conducted under ethylene epoxidation conditions with O2 at 1 atm and 200 ℃ on unpromoted Ag/α-Al2O3 catalysts with different Ag particle sizes. It was found that for Ag particles of 20–50 nm, the weight normalized conversion rate decreased rapidly with increasing Ag particle size but remained almost constant above 50 nm. On the other hand, the apparent TOF increased with increasing Ag particle sizes in the 20–170 nm studied range, while ethylene oxide selectivity at zero residence time was nearly constant (55 ± 4%). Raman bands at 815 (all Ag sizes) and 880 (Ag sizes > 100 nm) cm−1 were identified and assigned to active molecular oxygen species. The 880 cm−1 species was assigned to a molecular oxygen complex structure stabilized by subsurface oxygen. The presence of the 880 cm−1 oxygen species likely explain the higher apparent TOF in larger Ag particles (>100 nm)
Preliminary Evidence That Fiji Water Has Protective Effects against Aluminum Toxicity in Honey Bees (Apis mellifera)
Get PDFResearchers have determined that bioavailable aluminum chloride (AlCl3) may affect honey bee behavior (e.g., foraging patterns and locomotion) and physiology (e.g., abdominal spasms). The purpose of these experiments was to determine if Fiji water reduces the impacts of AlCl3 toxicity in bees by measuring circadian rhythmicity (number of times bees crossed the centerline during the day and night), average daily activity (average number of times bees crossed the centerline per day), and mortality rates (average number of days survived) using an automated monitor apparatus. Overall, the AlCl3 before and after Fiji groups had significantly higher average daily activity and rhythmicity rates compared to their respective AlCl3 before and after deionized water (DI) groups. One of the AlCl3 before DI groups exhibited no difference in rhythmicity rates compared to its respective AlCl3 after Fiji group. Overall, these results suggest that Fiji water might exert protective effects against AlCl3. The AlCl3 groups paired with Fiji water had higher activity and rhythmicity levels compared to the AlCl3 groups paired with DI. It is important for researchers to continue to study aluminum and possible preventatives for aluminum uptake
Impact of genus (Geotrigona, Melipona, Scaptotrigona) on the targeted 1H-NMR organic profile, and authenticity test by interphase emulsion of honey processed in cerumen pots by stingless bees in Ecuador
Get PDFThe biodiversity of Ecuadorian stingless bees is almost 200 species. Traditional pot-honey harvest in Ecuador is mostly done from nests of the three genera selected here Geotrigona Moure, 1943, Melipona Illiger, 1806, and Scaptotrigona Moure, 1942. The 20 pot-honey samples collected from cerumen pots and three ethnic honeys “abeja de tierra”, “bermejo”, and “cushillomishki” were analyzed for qualitative and quantitative targeted 1H-NMR honey profiling, and for the Honey Authenticity Test by Interphase Emulsion (HATIE). Extensive data of targeted organic compounds (41 parameters) were identified, quantified, and described. The three honey types were compared by ANOVA. Amino acids, ethanol, hydroxymethylfurfural, aliphatic organic acids, sugars, and markers of botanical origin. The number of phases observed with the HATIE were one in Scaptotrigona and three in Geotrigona and Melipona honeys. Acetic acid (19.60 ± 1.45 g/kg) and lactic acid (24.30 ± 1.65 g/kg) were particularly high in Geotrigona honey (in contrast to 1.3 g/kg acetic acid and 1.6 g/kg lactic acid in Melipona and Scaptotrigona), and with the lowest fructose + glucose (18.39 ± 1.68) g/100g honey compared to Melipona (52.87 ± 1.75) and Scaptotrigona (52.17 ± 0.60). Three local honeys were tested using PCA (Principal Component Analysis), two were assigned with a correct declared bee origin, but “bermejo” was not a Melipona and grouped with the Scaptotrigona cluster. However after HCA (Hierarchical Cluster Analysis) the three honeys were positioned in the Melipona-Scaptotrigona cluster. This research supports targeted 1H-NMR-based profiling of pot-honey metabolomics approach for multi-parameter visualization of organic compounds, as well as descriptive and pertained multivariate statistics (HCA and PCA) to discriminate the stingless bee genus in a set of Geotrigona, Melipona and Scaptotrigona honey types. The NMR characterization of Ecuadorian honey produced by stingless bees emphasizes the need for regulatory norms. A final note on stingless bee markers in pot-honey metabolites which should be screened for those that may extract phylogenetic signals from nutritional traits of honey. Scaptotrigona vitorum honey revealed biosurfactant activity in the HATIE, originating a fingerprint Honey Biosurfactant Test (HBT) for the genus in this set of pot-honeys
Care of plastic objects
Get PDFI routinely deal with plastics in my job as a library and archives conservator. Plastics conservation is a fairly new area for all of us, and conservators are still learning about how to care for these objects as they begin to actively deteriorate. Modern materials are challenging in new ways, with proprietary formulae, complex materials, and new deterioration challenges.
Today I will focus on the current research and what we can take away from it to meet daily needs in a museum. Sadly, there is not a “one-size-fits-all” solution for storage of all plastics, as different plastics have different needs.
This presentation comes out of my own research and tips I recently garnered from a webinar by Yvonne Shashoua, Research Professor at the University of Denmark—a chemist and leading researcher on plastics degradation.
Unless otherwise noted, all images come from KU Libraries, University of Kansas
Bond Behavior of Epoxy-Coated Reinforcing Bars in Non-Proprietary UHPC
Get PDFNon-proprietary ultra-high-performance concrete (UHPC) mixtures were developed for use in closure strips between precast members on reinforced concrete bridges. The mixtures contained ODOT approved Type I portland cement, slag cement, silica fume, graded fine aggregate, two high-range water-reducers (HRWRs), one of which incorporated a viscosity modifying admixture, and 2% by volume of 0.5-in. steel fibers. Several HRWRs of each type were included in the evaluations. Mixtures were evaluated based on flow, fiber distribution, flexural properties, compressive strength, and effect on bond strength using a modified pullout test and the ASTM A944 beam-end test for No. 5 uncoated, ASTM A755 epoxy-coated, and ASTM A1124 textured-epoxy-coated reinforcing bars. The UHPC mixture with the best properties was used to cast a closure strip between two precast sections to determine the splice strength of No. 4, No. 5, and No. 8 uncoated, epoxy-coated, and textured-epoxy-coated reinforcing bars with minimum clear covers ranging from 1.00 to 2.63 in. The results of the splice test were used to develop design recommendations. The study showed that UHPC can be made using ODOT approved materials. The splice strength of reinforcing bars in UHPC is two times the value in conventional concrete. The negative effects of epoxy coating on bond strength are lower in UHPC than in conventional concrete. ASTM A1124 textured epoxy-coated bars have the same bond strength as uncoated bars. The design procedures described in this report are based on UHPC with a minimum compressive strength at the time of load application of not less than 12 ksi, with a flow between 8 and 10 in. and good fiber distribution.Oklahoma Department of Transportation (ODOT SP&R Item Number 2290)Sherwin-WilliamsCommercial Metals CompanyGCP Applied TechnologiesMaster Builders SolutionsChryso and Midwest Concrete MaterialsDayton-Superio
Differences in countermovement vertical jump force-time metrics between starting and non-starting professional male basketball players
No full textWith force plates being widely implemented for neuromuscular performance assessment in sport-specific settings and various force-time metrics being able to differentiate athletes based on their performance capabilities, the purpose of the present study was to examine the differences in countermovement vertical jump (CVJ) characteristics between starting and non-starting professional male basketball players (e.g., ABA League). Twenty-three athletes (height = 199.2 ± 7.7 kg, body mass = 94.2 ± 8.2 kg, age = 23.8 ± 4.9 years) volunteered to participate in the present investigation. Upon completion of a standardized warm-up protocol, each athlete performed three maximal-effort CVJs without an arm swing while standing on a uni-axial force plate system sampling at 1,000 Hz. Independent t-tests were used to examine statistically significant differences (p < 0.05) in each force-time metric between starters (n = 10) and non-starters (n = 13). No significant differences in any of the CVJ force-time metrics of interest were observed between the two groups, during both the eccentric and concentric phases of the movement (i.e., impulse, duration, peak velocity, and mean and peak force and power). Moreover, starters and non-starters demonstrated similar performance on CVJ outcome (e.g., jump height) and strategy metrics (e.g., countermovement depth). Overall, these findings suggest that at the professional level of play, the ability to secure a spot in the starting lineup is not primarily determined by the players' CVJ performance characteristics
Continuity in Peirce's Lesson in Elocution: A Performance-based Approach
No full textPeirce's "Lesson in Elocution" (written ca. 1892) provides insight into his ideas on continuity and community through his knowledge of performance cultures such as theatre, elocution, rhetoric, and declamation. This unpublished manuscript constitutes the extant part of an application Peirce drafted to the Episcopal Church's General Theological Seminary for the position of elocution instructor. Continuing Henry C. Johnson, Jr.'s account (published in Transactions [2006] vol. 42, no. 4) of the Lesson as evidence of Peirce's religious practices, this article explores the Lesson as demonstration of his performance knowledge and experience. What would Peirce have brought as philosopher and scientist to the teaching of elocution? Conversely, what did his performance knowledge bring to his work on continuity and community? Outlining significant differences between Peirce's semiotic approach and that of the Seminary's then-current instructor, Francis Thayer Russell, the article argues, employing selected performance theory concepts, that performance often operates in semiosis itself, as Peirce defined it
Effects of aluminum-salt, CpG and emulsion adjuvants on the stability and immunogenicity of a virus-like particle displaying the SARS-CoV-2 receptor-binding domain (RBD) (Dataset)
No full textSecond-generation COVID-19 vaccines with improved immunogenicity (e.g., breadth, duration) and availability (e.g., lower costs, refrigerator stable) are needed to enhance global coverage. In this work, we formulated a clinical-stage SARS-CoV-2 receptor binding domain (RBD) virus-like particle (VLP) vaccine candidate (IVX-411) with widely available adjuvants. Specifically, we assessed the in vitro storage stability and in vivo mouse immunogenicity of IVX-411 formulated with aluminum-salt adjuvants (Alhydrogel™, AH and Adjuphos™, AP), without or with the TLR-9 agonist CpG-1018™ (CpG), and compared these profiles to IVX-411 adjuvanted with an oil-in-water nano-emulsion (AddaVax™, AV). Although IVX-411 bound both AH and AP, lower binding strength of antigen to AP was observed by Langmuir binding isotherms. Interestingly, AH- and AP-adsorbed IVX-411 had similar storage stability profiles as measured by antigen binding assays (competitive ELISAs), but the latter displayed higher pseudovirus neutralizing titers (pNT) in mice, at levels comparable to titers elicited by AV-adjuvanted IVX-411. CpG addition to alum (AP or AH) resulted in a marginal trend of improved pNTs in stressed samples only, yet did not impact the storage stability profiles of IVX-411. In contrast, previous work with AH-formulations of a monomeric RBD antigen showed greatly improved immunogenicity and decreased stability upon CpG addition to alum. At elevated temperatures (25, 37°C), IVX-411 formulated with AH or AP displayed decreased in vitro stability compared to AV-formulated IVX-411and this rank-ordering correlated with in vivo performance (mouse pNT values). This case study highlights the importance of characterizing antigen-adjuvant interactions to develop low cost, aluminum-salt adjuvanted recombinant subunit vaccine candidates