On the simplicial volumes of fibre bundles

We show that surface bundles over surfaces with base and fiber of genus at least 2 have non-vanishing simplicial volume.Comment: 4 pages, revised version, one reference added, to appear in the Proceedings of the AM

Investigation into the reactions of aliphatic methoxydiazo-ketones upon treatment with boron trifluoride etherate

This research was a study of the possible cyclization reactions of the aliphatic methoxydiazoketones (I) and (II) upon treatment with BF3 etherate. Previous work in this area had dealt with aromatic systems. J. Moore and H. Shaffer (10) showed that 1-diazo-3-(o-anisyl)-2-propanone (III) is converted in about 35% yield to chromanone (IV) upon treatment with BF3. They obtained lesser amounts of chromanone and larger amounts of open chain products when mineral acids were employed. Diazoketones such as (V) and (VI) have shown a pronounced tendency to form four-membered rings upon treatment with mineral acids. (8) No open chain products were isolated in the latter case even in the presence of excess nucleophile. The formation of five and six-membered rings has generally been limited to the sterically favorable ortho-substituted aromatic forms. Based on the fact that the Lewis Acid, BF3, gave the best yield of cyclic product in the aromatic system a similar result might be expected from the aliphatic series. The object of this research was to produce the cyclic compounds oxetanone-3 (VII) and tetrahydro-3-furanone (VIII) by the BF3 method. The diazoketones which appear in this paper will be written as RCOCHN2 although the actual structure is a resonance hybrid of the three forms

Reproductive Health and Morphometric Comparison of Catostomid Species in Two Midwestern Rivers

Wastewater treatment effluent, agricultural runoff, and impoundments can alter the water quality and flow regime of rivers. Fishes around the world are increasingly exposed to estrogenic compounds due to the discharge of wastewater into rivers. Estrogenic compounds, such as those found in birth control pills and soybean byproducts, are endocrine disruptors in vertebrates. The Sanitary District of Decatur serves the municipal and industrial entities of Macon County, IL, and discharges its effluent into the Sangamon River, which includes byproducts of industrial soybean processing. I assessed impacts of treated wastewater on the health of fishes in the Sangamon River. Abnormal caudal fins have been observed in several Catostomid species in the study reach of the Sangamon River. I assessed sex ratios, plasma vitellogenin concentrations, and the occurrence of gonadal intersex in three Catostomid species (River Carpsucker Carpiodes carpio, Smallmouth Buffalo Ictiobus bubalus, and Shorthead Redhorse Moxostoma macrolepidotum). I also assessed condition and morphometrics of these species to determine if relative weight is affected by fin morphology. Data were collected in spring of 2016 in the Sangamon and Embarras Rivers. All sexually mature fishes were sexed and blood was drawn from all adults identified as male and analyzed with ELISA test kits to determine vitellogenin concentrations. Fish testes were dissected, weighed, preserved for histology, and analyzed for the presence of testicular oocytes. No testicular oocytes were found in any of the species. Shorthead Redhorse from the Embarras River had a higher gonadosomatic index compared to fish from the Sangamon River, but no differences were found for River Carpsucker and Smallmouth Buffalo. Due to vitellogenin detection in a high percentage of males, populations were intersexed and female biased in both rivers for all species. Using traditional and geometric morphometrics, I used standard and total lengths to determine if River Carpsucker and Smallmouth Buffalo from the Sangamon River have significantly longer total lengths compared to standard lengths. River Carpsucker and Smallmouth Buffalo have longer caudal fins in the Sangamon River than the Embarras River. Longer caudal fins cause lower relative weight due to relative weight calculation incorporating total length. Geometric morphometrics revealed Sangamon River River Carpsucker and Smallmouth Buffalo have significantly different body shapes due to fin morphology than fishes in the Embarras River. The occurrence of feminization in both rivers, as well as the difference in body shapes between rivers, demonstrates these populations, especially in the Sangamon River, may be at risk for deterioration of health and further reproductive disruption due to contaminant exposure

Reproductive Health and Morphometric Comparison of Catostomid Species in Two Midwestern Rivers

Wastewater treatment effluent, agricultural runoff, and impoundments can alter the water quality and flow regime of rivers. Fishes around the world are increasingly exposed to estrogenic compounds due to the discharge of wastewater into rivers. Estrogenic compounds, such as those found in birth control pills and soybean byproducts, are endocrine disruptors in vertebrates. The Sanitary District of Decatur serves the municipal and industrial entities of Macon County, IL, and discharges its effluent into the Sangamon River, which includes byproducts of industrial soybean processing. I assessed impacts of treated wastewater on the health of fishes in the Sangamon River. Abnormal caudal fins have been observed in several Catostomid species in the study reach of the Sangamon River. I assessed sex ratios, plasma vitellogenin concentrations, and the occurrence of gonadal intersex in three Catostomid species (River Carpsucker Carpiodes carpio, Smallmouth Buffalo Ictiobus bubalus, and Shorthead Redhorse Moxostoma macrolepidotum). I also assessed condition and morphometrics of these species to determine if relative weight is affected by fin morphology. Data were collected in spring of 2016 in the Sangamon and Embarras Rivers. All sexually mature fishes were sexed and blood was drawn from all adults identified as male and analyzed with ELISA test kits to determine vitellogenin concentrations. Fish testes were dissected, weighed, preserved for histology, and analyzed for the presence of testicular oocytes. No testicular oocytes were found in any of the species. Shorthead Redhorse from the Embarras River had a higher gonadosomatic index compared to fish from the Sangamon River, but no differences were found for River Carpsucker and Smallmouth Buffalo. Due to vitellogenin detection in a high percentage of males, populations were intersexed and female biased in both rivers for all species. Using traditional and geometric morphometrics, I used standard and total lengths to determine if River Carpsucker and Smallmouth Buffalo from the Sangamon River have significantly longer total lengths compared to standard lengths. River Carpsucker and Smallmouth Buffalo have longer caudal fins in the Sangamon River than the Embarras River. Longer caudal fins cause lower relative weight due to relative weight calculation incorporating total length. Geometric morphometrics revealed Sangamon River River Carpsucker and Smallmouth Buffalo have significantly different body shapes due to fin morphology than fishes in the Embarras River. The occurrence of feminization in both rivers, as well as the difference in body shapes between rivers, demonstrates these populations, especially in the Sangamon River, may be at risk for deterioration of health and further reproductive disruption due to contaminant exposure

Junior Recital, Samantha Hoster, oboe

The presentation of this junior recital will fulfill in part the requirements for the Bachelor of Music degree in Music Education. Samantha Hoster studies oboe with Alyssa McKeithen

Single Rigid Ladder Safety Revision Affected by Ascent Biomechanics

The objective of this article is to review the critical conditions of a single beam ladder using the temporospatial ladder stability analysis with integrated biomechanical considerations. From the ergonomic perspective, the non-occupational incidents may involve even more critical parameters than the occupational incidents. This is because the occupational users are assumed to have necessary psychophysical abilities, experience, training and awareness of appropriate standards and regulations, and are moreover familiar with proper ladder settings and their utilization, unlike most of the non-occupational users. Such a perspective supports our safety concern about ladder use, especially for non-occupational environments, what is in focus of this article. Computational modelling of expected ladder ascent and usage were exploited, with taking into consideration the real time kinetics and kinematics, anthropometry of the climber and variable contact friction factors. The results are shown in a parametric diagram, that revises and confirms the guideline for setting the ladder slant at 75,5°. Then, regardless of the climber’s mass, the intensity of the ascent (period or cycle duration, hence the extremes in acceleration), and of the low coefficient of friction at the ground contact, the climb is safe. Created computational ladder model and representative equations are validated, henceforth the created computational model is attributed the ability to revise the ladder use recommendations. Created and validated model is expected to makes possible a further extension of the set of the considered and analysed ladder usage parameters. Hence, inclusivity of wider range of parameters of ladder utilization and design is expected to reveal other underestimated or neglected factors that might appear as critical ones

Electrochemical kinetics:a surface-science supported picture of hydrogen electrochemistry on Ru(0001) and Pt/Ru(0001)

In this short review, we compare the kinetics of hydrogen desorption in vacuum to those involved in the electrochemical hydrogen evolution/oxidation reactions (HER/HOR) at two types of atomically smooth model surfaces: bare Ru(0001), and the same surface covered by a 1.1 atomic layer thick Pt film. Low/high H2 (D2) desorption rates at room temperature in vacuum quantitatively correspond to low/high exchange current densities for the HOR/HER in electrochemistry. In view of the “volcano plot” concept, these represent two surfaces that adsorb hydrogen atoms, Had, too strongly and too weakly, respectively. Atomically smooth, vacuum annealed model surfaces are the closest approximation to the idealised slab geometries typically studied by density functional theory (DFT). A predictive volcano plot based on DFT-based adsorption energies for the Had intermediates agrees well with the experiments if two things are considered: (i) the steady-state coverage of Had intermediates and (ii)local variations in film thickness. The sluggish HER/HOR kinetics of Ru(0001) allows for excellent visibility of cyclic voltammetry (CV) features even in H2 saturated solution. The CV switches between a Had and a OHad/Oad dominated regime, but the presence of H2 in the electrolyte increases the Had dominated potential window by a factor of two. Whereas in plain electrolyte two electrochemical adsorption processes compete in forming adlayers, it is one electrochemical and one chemical one in the case of H2 saturated electrolyte. We demonstrate and quantitatively explain that dissociative H2 adsorption is more important than H+ discharge for Had formation in the low potential regime on Ru(0001)

Ultrahigh vacuum and electrocatalysis:the powers of quantitative surface imaging

We highlight the impact of Ultrahigh Vacuum (UHV)-born surface science on modern electrocatalysis. The microscopic, atomic level picture of surface adsorption and reaction, which was developed in the surface science community in decades of systematic research on single crystals in UHV, has meanwhile become state-of-the-art also in electrochemistry. For the example of CO on Pt(111) single crystals, which has been extensively studied at the solid/gas and the solid/liquid interface using atomic resolution scanning tunnelling microscopy (STM), we highlight how both interfaces may have even more in common than often assumed. We then illustrate how planar model surfaces such as mono- and bimetallic single crystals and surface alloys, prepared and thoroughly analysed in UHV, enabled a systematic search for improved electrocatalysts. Surface alloys, thermodynamically more stable than foreign metal islands, are a particularly important sub-group of model surfaces, which so far have only been fabricated in UHV. We also flag that model surfaces may not always assume the structure anticipated for the respective experiment, regardless of their preparation in UHV or by electrochemical methods. “Accidental” surface alloying may be more common than often assumed, leading to misinterpretations of the structure-property relationships targeted in many model studies. We highlight that controlled surface alloy formation should be a key step in any model study looking at bimetallic systems in order to get an idea what the effect of unintended alloying could possibly be, and to cross-check whether alloyed surfaces may potentially be the better electrocatalysts in the first place