Minnesota Hybrid Corn: Field Trials, 1938

This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu

Vibrational relaxation of CH3I in the gas phase and in solution

This is the publisher's version, also available electronically from http://scitation.aip.org/content/aip/journal/jcp/120/15/10.1063/1.1676292.Transient electronic absorption measurements reveal the vibrational relaxation dynamics of CH(3)I following excitation of the C–H stretch overtone in the gas phase and in liquid solutions. The isolated molecule relaxes through two stages of intramolecular vibrational relaxation (IVR), a fast component that occurs in a few picoseconds and a slow component that takes place in about 400 ps. In contrast, a single 5–7 ps component of IVR precedes intermolecular energy transfer (IET) to the solvent, which dissipates energy from the molecule in 50 ps, 44 ps, and 16 ps for 1 M solutions of CH(3)I in CCl(4), CDCl(3), and (CD(3))(2)CO, respectively. The vibrational state structure suggests a model for the relaxation dynamics in which a fast component of IVR populates the states that are most strongly coupled to the initially excited C–H stretch overtone, regardless of the environment, and the remaining, weakly coupled states result in a secondary relaxation only in the absence of IET

Vibrational relaxation of CH(2)I(2) in solution: Excitation level dependence

This is the publisher's version, also available electronically from http://scitation.aip.org/content/aip/journal/jcp/118/12/10.1063/1.1554396.Transient electronic absorption monitors the flow of vibrational energy in methylene iodide (CH(2)I(2)) following excitation of five C–H stretch and stretch–bend modes ranging in energy from 3000 to 9000 cm(−1). Intramolecular vibrational relaxation (IVR) occurs through a mechanism that is predominantly state-specific at the C–H stretch fundamental but closer to the statistical limit at higher excitation levels. The IVR times change with the excitation energy between the fundamental and first C–H stretch overtone but are constant above the overtone. The intermolecular energy transfer (IET) times depend only weakly on the initial excitation level. Both the IVR and the IET times depend on the solvent[CCl(4), CDCl(3), C(6)D(6), C(6)H(6), or (CD(3))(2)CO] and its interaction strength, yet there is no energy level dependence of the solvent influence

Rag doll test for seed corn

7 pages; includes photographs and drawing. This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu

Barley in Minnesota

12 pages; includes photographs. This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu

Risk factors for exacerbations and pneumonia in patients with chronic obstructive pulmonary disease: a pooled analysis.

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) are at risk of exacerbations and pneumonia; how the risk factors interact is unclear. METHODS: This post-hoc, pooled analysis included studies of COPD patients treated with inhaled corticosteroid (ICS)/long-acting β2 agonist (LABA) combinations and comparator arms of ICS, LABA, and/or placebo. Backward elimination via Cox's proportional hazards regression modelling evaluated which combination of risk factors best predicts time to first (a) pneumonia, and (b) moderate/severe COPD exacerbation. RESULTS: Five studies contributed: NCT01009463, NCT01017952, NCT00144911, NCT00115492, and NCT00268216. Low body mass index (BMI), exacerbation history, worsening lung function (Global Initiative for Chronic Obstructive Lung Disease [GOLD] stage), and ICS treatment were identified as factors increasing pneumonia risk. BMI was the only pneumonia risk factor influenced by ICS treatment, with ICS further increasing risk for those with BMI <25 kg/m2. The modelled probability of pneumonia varied between 3 and 12% during the first year. Higher exacerbation risk was associated with a history of exacerbations, poorer lung function (GOLD stage), female sex and absence of ICS treatment. The influence of the other exacerbation risk factors was not modified by ICS treatment. Modelled probabilities of an exacerbation varied between 31 and 82% during the first year. CONCLUSIONS: The probability of an exacerbation was considerably higher than for pneumonia. ICS reduced exacerbations but did not influence the effect of risks associated with prior exacerbation history, GOLD stage, or female sex. The only identified risk factor for ICS-induced pneumonia was BMI <25 kg/m2. Analyses of this type may help the development of COPD risk equations

Oats in Minnesota

8 pages; includes 1 photograph. This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu

Bond selective dissociation of methane (CH3D) on the steps and terraces of Pt(211)

The dissociative chemisorption of singly deuterated methane (CH3D) has been studied on the steps and terraces of a Pt(211) surface by quantum state resolved molecular beam methods. At incident translational energy (Et) below 50 kJ/mol, CH3D dissociates only on the more reactive steps of Pt(211), where both C–H and C–D cleavage products CH2D(ads) and CH3(ads) can be detected by reflection absorption infrared spectroscopy. Vibrational excitation of a slow beam of CH3D (Et = 10 kJ/mol), prepared with one quantum of antisymmetric C–H stretch excitation by infrared laser pumping, allows for fully bond- and site-selective dissociation forming exclusively CH2D(ads) on the step sites. At higher kinetic energies (Et > 30 kJ/mol), bond selective dissociation by C–H bond cleavage is observed on the terrace sites for stretch excited CH3D (ν4) while on the steps, the C–H/C–D cleavage branching ratio approaches the statistical 3/1 limit. Finally, at Et > 60 kJ/mol, both C–H and C–D cleavages are observed on both step and terrace sites of Pt(211). Our experiments show how careful control of incident translational and vibrational energy can be used for site and bond selective dissociation of methane on a catalytically active Pt surface

IDENTIFICAZIONE DELLE LESIONI POLMONARI IN RM CON UNA SEQUENZA VIBE MODIFICATA E CON UNA SEQUENZA VIBE STANDARD: UN CONFRONTO CON LA TC.

Scopo valutare l\u2019accuratezza della RM a 3 Tesla nell\u2019individuazione di lesioni polmonari con una sequenza VIBE modificata e con una sequenza VIBE standard, usando la TC come riferimento. Materiale e metodi abbiamo rivalutato retrospettivamente 37 pazienti oncologici (11 pediatrici e 26 adulti; 19 F) sottoposti a TC e PET/RM da 3T il cui protocollo prevedeva una sequenza VIBE acquisita a respiro trattenuto con echo time (TE) di 0.89 ms e flip angle (FA) di 3\ub0. Le VIBE sono state valutate da tre osservatori per l'identificazione di noduli >5mm o =5mm. Un quarto osservatore ha valutato delle sequenze VIBE standard (TE di 1.2 ms e FA di 10\ub0), anch\u2019esse incluse nel protocollo, ed infine un quinto lettore ha analizzato le immagini TC (considerate come standard di riferimento).Sia per paziente che per singola lesione sono state calcolate sensibilit\ue0 e specificit\ue0 per le due categorie di noduli ed il coefficiente di correlazione intraclasse (ICC) per i lettori delle VIBE modificate. Risultati analisi per paziente (positivit\ue0=1 lesione): sensibilit\ue0 84.6% e specificit\ue0 di 100% per noduli>5mm (VIBE standard 69.2% e 100%) e 44.4% e 100% per noduli=5mm (VIBE standard 33.3% e 100%). Analisi per lesione (presenza/assenza): sensibilit\ue0 di 83.9% per noduli>5mm (VIBE standard 67.74%) e 37.5% per noduli=5mm (VIBE standard 18.7%). L\u2019ICC nell\u2019analisi per paziente era 0.911 per noduli>5mm e 0.902 per noduli=5mm; nell\u2019analisi per lesione 0.866 per noduli>5mm e 0.699 per noduli=5mm. Conclusioni la sequenza VIBE modificata \ue8 riproducibile ed accurata per l\u2019individuazione di noduli >5mm, mentre l\u2019accuratezza risulta meno soddisfacente per i noduli=5mm. L\u2019utilizzo della sequenza modificata nei protocolli RM sembra ragionevole per migliorare la visualizzazione del polmone