METR 100: Weather and Climate–Peer Review of Teaching Project Benchmark Portfolio

The target course for this benchmark portfolio is METR 100: Weather and Climate, an introductory-level course about Earth’s weather and climate. Students enrolled span all undergraduate class levels and during the spring semester most students are non-science majors. Through the Peer Review of Teaching Project, this course was re-designed to better align the course objectives with the University of Nebraska – Lincoln’s Achievement Centered Education (ACE) program. The number of topics covered during the semester was reduced and time spent practicing skills was increased in an effort to improve student attainment of course goals. This portfolio outlines course objectives, pedagogical approaches and describes course activities that were used to give students practice with the desired skills. It includes a discussion of the development and implementation of an assessment tool (pre-post-test) for evaluating student achievement of the learning goals. The results of the assessment suggest that decreasing the number of topics covered and increasing the amount of time spent working toward the learning goals had a positive effect on student achievement of the learning goals

Less is More: Course Redesign and the Development of an Atmospheric Science Process Skills Assessment

General education science courses strive to promote scientific literacy and the development of scientific process skills. However, research shows that many general education courses are still designed to stress content mastery. In this study, the number of topics in five semester-long introductory atmospheric science courses was reduced to increase time for the development of scientific process skills, a critical component of scientific literacy. The Atmospheric and Climate Science Literacy Frameworks and a general science education skills rubric were used to guide the course redesign and development of course activities. Details of the course structure and sample course activities are described. A pre-post-test was developed to evaluate attainment of five scientific process skills and the efficacy of the course redesign. Preliminary validity and reliability studies suggest that the majority of the assessment questions are reliable, though further validation of the assessment is required

Risk of climate-induced damage in historical textiles

Eleven wool and silk historic textiles and two modern artist's canvases were examined to determine their water vapour adsorption, moisture dimensional response and tensile behaviour. All the textiles showed a similar general pattern of moisture response. A rise in ambient relative humidity (RH) from dry conditions produced expansion of a textile until a certain critical RH level after which a contraction occurred to a greater or lesser degree depending on the yarn crimp and the weave geometry. The largest expansion recorded between the dry state and 80% RH was 1.2 and 0.9% for wool and silk textiles, respectively. The largest shrinkage of 0.8% at high RH range was experienced by a modern linen canvas. Two potential damage mechanisms related to the moisture response of the textiles—stress building as a result of shrinkage of the textile restrained in its dimensional response and the fretting fatigue when yarns move with friction one against another—were found insignificant in typical textile display environments unless the textiles are severely degraded or excessively strained in their mounting

Origin and radiative forcing of black carbon transported to the Himalayas and Tibetan Plateau

The remote and high elevation regions of central Asia are influenced by black carbon (BC) emissions from a variety of locations. BC deposition contributes to melting of glaciers and questions exist, of both scientific and policy interest, as to the origin of the BC reaching the glaciers. We use the adjoint of the GEOS-Chem model to identify the location from which BC arriving at a variety of locations in the Himalayas and Tibetan Plateau originates. We then calculate its direct and snow-albedo radiative forcing. We analyze the seasonal variation in the origin of BC using an adjoint sensitivity analysis, which provides a detailed map of the location of emissions that directly contribute to black carbon concentrations at receptor locations. We find that emissions from northern India and central China contribute the majority of BC to the Himalayas, although the precise location varies with season. The Tibetan Plateau receives most BC from western and central China, as well as from India, Nepal, the Middle East, Pakistan and other countries. The magnitude of contribution from each region varies with season and receptor location. We find that sources as varied as African biomass burning and Middle Eastern fossil fuel combustion can significantly contribute to the BC reaching the Himalayas and Tibetan Plateau. We compute radiative forcing in the snow-covered regions and find the forcing due to the BC induced snow-albedo effect to vary from 5–15 W m<sup>−2</sup> within the region, an order of magnitude larger than radiative forcing due to the direct effect, and with significant seasonal variation in the northern Tibetan Plateau. Radiative forcing from reduced snow albedo likely accelerates glacier melting. Our analysis may help inform mitigation efforts to slow the rate of glacial melt by identifying regions that make the largest contributions to BC deposition in the Himalayas and Tibetan Plateau

On the near-wall accumulation of injectable particles in the microcirculation: smaller is not better

Although most nanofabrication techniques can control nano/micro particle (NMP) size over a wide range, the majority of NMPs for biomedical applications exhibits a diameter of ~100 nm. Here, the vascular distribution of spherical particles, from 10 to 1,000 nm in diameter, is studied using intravital microscopy and computational modeling. Small NMPs (≤100 nm) are observed to move with Red Blood Cells (RBCs), presenting an uniform radial distribution and limited near-wall accumulation. Larger NMPs tend to preferentially accumulate next to the vessel walls, in a size-dependent manner (~70% for 1,000 nm NMPs). RBC-NMP geometrical interference only is responsible for this behavior. In a capillary flow, the effective radial dispersion coefficient of 1,000 nm particles is ~3-fold larger than Brownian diffusion. This suggests that sub-micron particles could deposit within diseased vascular districts more efficiently than conventional nanoparticles

Source attribution and interannual variability of Arctic pollution in spring constrained by aircraft (ARCTAS, ARCPAC) and satellite (AIRS) observations of carbon monoxide

We use aircraft observations of carbon monoxide (CO) from the NASA ARCTAS and NOAA ARCPAC campaigns in April 2008 together with multiyear (2003–2008) CO satellite data from the AIRS instrument and a global chemical transport model (GEOS-Chem) to better understand the sources, transport, and interannual variability of pollution in the Arctic in spring. Model simulation of the aircraft data gives best estimates of CO emissions in April 2008 of 26 Tg month−1 for Asian anthropogenic, 9.4 for European anthropogenic, 4.1 for North American anthropogenic, 15 for Russian biomass burning (anomalously large that year), and 23 for Southeast Asian biomass burning. We find that Asian anthropogenic emissions are the dominant source of Arctic CO pollution everywhere except in surface air where European anthropogenic emissions are of similar importance. Russian biomass burning makes little contribution to mean CO (reflecting the long CO lifetime) but makes a large contribution to CO variability in the form of combustion plumes. Analysis of two pollution events sampled by the aircraft demonstrates that AIRS can successfully observe pollution transport to the Arctic in the mid-troposphere. The 2003–2008 record of CO from AIRS shows that interannual variability averaged over the Arctic cap is very small. AIRS CO columns over Alaska are highly correlated with the Ocean Niño Index, suggesting a link between El Niño and Asian pollution transport to the Arctic. AIRS shows lower-than-average CO columns over Alaska during April 2008, despite the Russian fires, due to a weakened Aleutian Low hindering transport from Asia and associated with the moderate 2007–2008 La Niña. This suggests that Asian pollution influence over the Arctic may be particularly large under strong El Niño conditions

Effect of epinephrine on lidocaine clearance in vivo: a microdialysis study in humans.

Background: Local anesthetic nerve block prolonged by epinephrine is thought to result from local vasoconstriction and consequent decreased local anesthetic clearance from the injection site. However, no study has yet confirmed this directly in humans by measuring tissue concentrations of local anesthetic over time. In addition, recent studies have shown that the ␣ 2 -adrenergic receptor agonist, clonidine, also prolongs nerve block without altering local anesthetic clearance. Because epinephrine is also an ␣ 2 -adrenergic receptor agonist, it is possible that epinephrine prolongs local anesthetic block by a pharmacodynamic mechanism and not a pharmacokinetic one. This study was designed to address this issue. Methods: Microdialysis probes were placed adjacent to the superficial peroneal nerve in both feet of eight volunteers. Plain lidocaine (1%) was injected along one peroneal nerve and lidocaine with epinephrine (2.5 g/ml) was injected along the other nerve in a double-blinded, randomized manner. The concentration of lidocaine in tissue was measured at 5-min intervals, and sensory block and cutaneous blood flow were assessed by laser Doppler at 10-min intervals for 5 h. The resulting data for lidocaine concentration versus time were fit to a two-compartment model using modeling software. Results: Epinephrine prolonged sensory block by decreasing local blood flow and slowing clearance. There was no evidence of a pharmacodynamic effect of epinephrine. Conclusion: Although epinephrine activates ␣ 2 -adrenergic receptors, its mechanism for prolonging the duration of local anesthetic block rests on its ability to decrease local anes

Selektivno određivanje Fe(III) u uzorcima Fe(II) UV-spektrofotometrijom pomoću kvercetina i morina

Selective UV-spectrophotometric methods for determination of iron(III) in iron(II) samples have been developed. The methods are based on the interaction of Fe(III) with quercetin and morin, compounds of the flavonoid group. Redox reactions occurring between Fe(III) ions and the reagents used make the basis for the detection. Iron(II) does not react with quercetin and morin under the conditions applied [aqueous-methanolic (3 : 2) solutions, 0.3 mol L1 HCl, and 1.2 × 10-4 mol L1 quercetin (morin)] and does not interfere with the determination of Fe(III). Iron(III) can be determined up to 15 μg mL1 using both the examined systems. The detection limits are 0.06 and 0.38 μg mL1 when using quercetin or morin, respectively. The method with quercetin was applied to the determination of Fe(III) (ca. 0.2%) in a Fe(II) pharmaceutical product.U radu je opisan razvoj selektivnih UV-spektrofotometrijskih metoda za određivanje željeza(III) u uzorku željeza(II). Metode se temelje na redoks reakciji Fe(III) sa spojevima iz skupine flavonoida kvercetinom i morinom u reakcijskim uvjetima u kojima željezo(II) ne reagira (vodeno/metanolna otopina 3:2, 0,3 mol L1 HCl, 1,2 x 104 mol L1 kvercetin ili morin). Najniža koncentracija željeza(III) koja se može odrediti je 15 μg mL1 u oba ispitivana sustava. Granice detekcije su 0,06 i 0,38 μg mL1 ako se koristi kvercetin, odnosno morfin. Metoda s kvercetinom primijenjena je za određivanje Fe(III (približno 0,2%) u farmaceutskom produktu Fe(II)