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Well-designed laboratories can help students master content and science practices by successfully completing the laboratory experiments. Upper-division chemistry laboratory courses often present special challenges for instruction due to the instrument intensive nature of the experiments. To address these challenges, particularly those associated with rotation style course structures, pre-laboratory videos were generated for two upper-division laboratory courses, Analytical Measurements and Physical Measurements. Sets of videos were developed for each experiment: a pre-laboratory lecture, an experimental, and a data analysis video. We describe the theoretical principles that guided the design of the instructional videos as well as the process. To assess the impact of the videos on students' successful completion of the experiments, a mixed-methods approach to data collection was used, which included video-recorded laboratory observations, student one-on-one interviews, and the Meaningful Learning in the Laboratory Inventory (MLLI) survey. Our findings indicate that video-based resources can help alleviate some challenges associated with rotation-style labs, particularly the temporal disconnect between pre-laboratory lectures and experiment completion as well as the need for more student autonomy in upper-division laboratory courses.

Ionic liquids (ILs) add complexity to electrochemical interfaces that cannot be adequately treated with traditional double layer models. We present a series of carefully controlled capacitance measurements to optimize the collection of reproducible and uniform capacitance-potential datasets. We quantitatively evaluate analysis methods on the experimentally observed capacitance of l-ethyl-3-methylimidazolium trifluoromethauesulfonate [Emim][TFO] IL at the gold-IL interface. The major outcomes of our work are to identify how experimental data collection methods affect capacitive hysteresis, and to suggest a systematic approach to collect reproducible capacitance data for IL systems. We evaluate different potential scan directions, examine varying potential sweep rates, and capacitance collection methods. We find that faster scan rates can mitigate the capacitive hysteresis between the anodic and cathodic scans for a particular collection technique. However, faster scan rates also result in more variation between the collection techniques. We also find that decreasing the effective potential sweep rate reduces hysteresis between different collection techniques when other factors are held constant. It is crucial for researchers to consistently report the direction of the potential sweep and the effective rate of potential sweep. Our data suggest that using slower effective potential perturbation rates would reduce discrepancies in capacitance data collected from different laboratories under different experimental conditions. [ABSTRACT FROM AUTHOR]

Abstract Background The braconid subfamily Rogadinae is a large, cosmopolitan group of endoparasitoid wasps characterised by 'mummifying' their lepidopteran host larvae, from which the adult subsequently emerges. Rogadines attack a variety of both macro- and microlepidopteran taxa, although the speciose genus Aleiodes almost exclusively attacks macrolepidopterans. Here, we investigate the phylogenetic history of the Rogadinae, revise their higher-level classification and assess the evolution of their host ranges and mummy types. We also assess the divergence times within the subfamily and discuss the reasons for the extraordinary evolutionary diversification of Aleiodes. Results Our Bayesian analyses weakly support the monophyly of the subfamily. A clade comprising all Aleiodes species and some other taxa is not nested within the tribe Rogadini as previously supposed, but instead is recovered as sister to the Yeliconini, with the remaining Rogadini genera being recovered as sister to the Stiropiini. The Rogadinae is estimated to have originated during the mid to late Eocene, 36.1–51.62 MYA. Molecular dating gives a more recent origin for the Aleiodes clade (17.98–41.76 MYA) compared to the origins proposed for two of its principal lepidopteran host groups (Noctuidae: 60.7–113.4 MYA; Geometridae 48–62 MYA). The Bayesian ancestral reconstruction of the emergence habits from the mummified hosts weakly recovered an anterior emergence as the ancestral condition for the subfamily. Producing a hard mummy has evolved at various times independently, though most of the species with this biology belong to the Aleiodes clade. Conclusion Based on our results, we erect the tribe Aleiodini nov. to include Aleiodes and Heterogamus stat. rev. Cordylorhogas, Pholichora and Hemigyroneuron are synonymised with Aleiodes. The molecular dating of clades and the ancestral reconstruction of host ranges support the hypothesis that radiation within Aleiodes s. s. was due to host recruitment leading to host range expansion followed by speciation, and not to parasitoid-host coevolution. Within the Rogadinae, variation in the site of emergence from the mummified host probably evolved as a consequence of the mummy's site and mode of formation, and the extent of mummy tanning/hardness to the degree of protection needed in relation to the cost of providing it.

The electrochemical reduction of atmospheric carbon dioxide to value added chemicals and fuels using renewable energy is a promising route to a sustainable economy. In this work we present results from the electrochemical reduction of carbon dioxide on copper/silver alloy electrodes alongside pure copper and pure silver in acetonitrile-water electrolyte mixtures. EIS measurements show that the copper/silver alloys exhibit lower charge-transfer resistance when compared to the pure metal electrodes. Reduced product analysis identifies carbon monoxide (CO) as the major product on pure Ag, Ag with alloyed with 10% Cu, and Cu alloyed with 10% Ag with Faradaic efficiencies over 60%. Formate is the major reduced product close to the 50:50 (Cu:Ag) ratio with Faradaic efficiencies exceeding 30%. Our results suggest that changes in the metallic lattice and structural strain of the bimetallic electrodes influences reduced product selectivity. [ABSTRACT FROM AUTHOR]

In this work, we conduct a systematic experimental investigation of surface integrity for steel and aluminum alloys processed via nanosecond laser-based high-throughput surface nanostructuring (nHSN) process. nHSN surface morphology and surface chemistry are first experimentally characterized, and the results show that surface nanostructure with proper surface chemistry is generated due to the combined effect of chemical etching and attachment of functional groups of low surface energy. Desired surface wetting behavior is achieved using a proper silane reagent during the nHSN chemical immersion treatment phase, while surface nanostructure can be finely modulated by adjusting the laser processing parameters. nHSN nanostructures with fluorosilane chemistry exhibit strong capability to repel water, leading to superhydrophobicity achieved on two important engineering metal alloys, namely steel and aluminium alloys. It is further experimentally demonstrated that the microhardness and anti-corrosion performance of the nHSN surface can be significantly enhanced compared with the untreated surface, indicating that the nHSN process is very effective for enhancing the mechanical strength and corrosion resistance of these important metal alloys. These results show that nHSN simultaneously creates random nanostructures, attains desirable surface chemistry and enhances surface integrity over large-area metal alloy surfaces. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Veterinary Journal / Revue Vétérinaire Canadienne is the property of Canadian Veterinary Medical Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article explored the commonly-assumed notion that the Libyan Civil War generated the current conflict in Mali. It applies the causal mechanisms from the theories of escalation and diffusion or contagion to the issue in order to determine the link between conflict in both the two countries and found that Libyan Civil War is respinsible for conflict in Mali and also dicuses ways by which the conflict can spread out of Mali in other neighboring countries.

Background Thromboembolism has recently been described as a complication following treatment for idiopathic thrombocytopenic purpura ( ITP). This pilot study was undertaken to determine whether dogs suffering from ITP experience hypercoagulability during treatment and recovery. Study design Thromboelastograms ( TEG) were performed on dogs with ITP within 24 hours of admission to the hospital, the first day the platelet count exceeded 40 × 109/L (Day 1), and on Days 4, 7, and 14. Key findings All dogs had hypocoagulable TEG tracings on initial admission to the hospital, but developed TEG tracings suggestive of hypercoagulability during the study period as indicated by increased maximum amplitude. Significance Dogs with ITP developed changes on TEG consistent with hypercoagulability during the study period. Many factors are likely to contribute to these changes. The clinical risk of thrombosis in these patients is unknown. [ABSTRACT FROM AUTHOR]

A medication error resulted in two kittens being treated with azathioprine (12 and 12.5 mg/kg) instead of azithromycin for 2 weeks. On clinical examination, the kittens were febrile, weak, and had oronasal hemorrhage. Complete blood cell counts indicated severe bone marrow suppression. Treatment consisted of multiple transfusions, antibiotics, and granulocyte colony-stimulating factor. One of the kittens responded to therapy and had a complete recovery. The other kitten was treated for 40 days with no clinical response before dying. Both kittens also contracted Mycoplasma hemofelis infection from a contaminated blood transfusion. [ABSTRACT FROM AUTHOR]

The case records of 20 dogs that were treated for tetanus between 1988 and 2004 were reviewed. Young, large-breed dogs were most commonly affected. Twelve dogs had a likely source of infection identified. All dogs were treated with intravenous antibiotics and supportive care, such as muscle relaxants and sedation for muscle tremors and rigidity. Sixteen dogs received tetanus antitoxin. The mortality rate was 50%. Complete recovery in survivors required approximately 1 month. J Am Anim Hosp Assoc 2007;43:143-148. [ABSTRACT FROM AUTHOR]