One-step synthesis of pyridines and dihydropyridines in a continuous flow microwave reactor

The Bohlmann–Rahtz pyridine synthesis and the Hantzsch dihydropyridine synthesis can be carried out in a microwave flow reactor or using a conductive heating flow platform for the continuous processing of material. In the Bohlmann–Rahtz reaction, the use of a Brønsted acid catalyst allows Michael addition and cyclodehydration to be carried out in a single step without isolation of intermediates to give the corresponding trisubstituted pyridine as a single regioisomer in good yield. Furthermore, 3-substituted propargyl aldehydes undergo Hantzsch dihydropyridine synthesis in preference to Bohlmann–Rahtz reaction in a very high yielding process that is readily transferred to continuous flow processing

Testing for Budget Constraint Effects in a National Advisory Referendum Survey on the Kyoto Protocol

In contrast to providing standard reminders about remembering household budgets, does asking survey respondents about their discretionary income and its use affect their voting responses in a national advisory referendum survey? We explore this question using U.S. household data from a unique set of multi-mode random samples (telephone and Internet surveys), and an advisory referendum concerning the Kyoto Protocol. The contingent valuation method is applied to estimate household willingness to pay (WTP) for a split-sample treatment: respondents who only received a standard reminder of household budgets (control group) versus respondents who received two mental accounting-type questions on discretionary income and its uses (treatment group). Results indicate that the treatment significantly influences voting responses and lowers estimated household WTP.budget constraint, contingent valuation, Kyoto Protocol, mental accounts, referendum, Environmental Economics and Policy,

Exploring the Beta Model Using Proportional Budget Information in a Contingent Valuation Study

Using a set of random telephone and Internet (web-based) survey samples for a national advisory referendum, we implement Beta models to handle proportional budget information, and allow for consistency in modeling assumptions and the calculation of estimated willingness to pay (WTP). Results indicate significant budget constraint effects and demonstrate the potential for Beta models in handling mental-accounting type information.Beta model

Seabed corrugations beneath an Antarctic ice shelf revealed by autonomous underwater vehicle survey: Origin and implications for the history of Pine Island Glacier

Ice shelves are critical features in the debate about West Antarctic ice sheet change and sea level rise, both because they limit ice discharge and because they are sensitive to change in the surrounding ocean. The Pine Island Glacier ice shelf has been thinning rapidly since at least the early 1990s, which has caused its trunk to accelerate and retreat. Although the ice shelf front has remained stable for the past six decades, past periods of ice shelf collapse have been inferred from relict seabed "corrugations" (corrugated ridges), preserved 340 km from the glacier in Pine Island Trough. Here we present high-resolution bathymetry gathered by an autonomous underwater vehicle operating beneath an Antarctic ice shelf, which provides evidence of long-term change in Pine Island Glacier. Corrugations and ploughmarks on a sub-ice shelf ridge that was a former grounding line closely resemble those observed offshore, interpreted previously as the result of iceberg grounding. The same interpretation here would indicate a significantly reduced ice shelf extent within the last 11 kyr, implying Holocene glacier retreat beyond present limits, or a past tidewater glacier regime different from today. The alternative, that corrugations were not formed in open water, would question ice shelf collapse events interpreted from the geological record, revealing detail of another bed-shaping process occurring at glacier margins. We assess hypotheses for corrugation formation and suggest periodic grounding of ice shelf keels during glacier unpinning as a viable origin. This interpretation requires neither loss of the ice shelf nor glacier retreat and is consistent with a "stable" grounding-line configuration throughout the Holocene