An expanding carbon cap-and-trade regime? A decade of experience with RGGI charts a path forward

On carbon, states have been forced by federal inaction to take matters into their own hands. Over a dozen states are participating in or considering CO₂ cap-and-trade regimes. The oldest – the Regional Greenhouse Gas Initiative – has in a decade achieved emission reductions through joint state implementation and efficient market-based carbon pollution control. The initiative also has yielded $5 billion in economic benefits and tens of thousands of jobs. RGGI thus charts a path forward for states seeking a practical approach to carbon reduction in the absence of federal leadership.     

Thermal stability of nanocrystalline Ni- and Co-based pulsed current electrodeposits: correlation of calorimetric measurements and microstructure development upon annealing

The exceptional properties associated with nanocrystalline materials are, to a large extent, a result of their high inter-crystalline volume fraction. However, the intrinsic instability of the nanostructured state may compromise the gain in properties by the occurrence of grain growth during exposure at elevated temperatures. Thermal stability is, therefore, a fundamental materials issue for nanocrystalline materials. This article describes what can be deduced from calorimetric measurements in the context of what is known about the microstructural evolution upon annealing of nanocrystalline Ni- and Co-based pulsed current electrodeposits. Special emphasis is put on interpreting the shape of the curves obtained by a differential scanning calorimetry (DSC). The temperature ranges for relaxation, segregation, precipitation, as well as abnormal and normal grain growth can be predicted. Also, by evaluating the shift in peak temperature with heating rate (Kissinger plot), the activation energies for grain growth can be obtained for the different materials.     

Thermally induced variation in barrier height and ideality factor of Ni/Au contacts to p-GaN

In this paper, we describe the change in barrier heights (ϕ_B) and ideality factors (n) of Ni/Au contacts to p-GaN determined from current-voltage measurements as a result of (a) rapid thermal annealing between 400–700°C under flowing nitrogen, and (b) testing at temperatures of 20–300°C. The lowest barrier height and ideality factor values were obtained from samples annealed at 500–600°C. These results provide supporting evidence that thermal processing helps to remove contaminants at the contact-GaN interface, thus decreasing effective barrier height and consequently, contact resistance.     

An examination of depression in the spouses of stroke patients.

Examined the prevalence and correlates of depression in the spouses (SPs [mean age 61.8 yrs]) of 41 stroke patients (SPTs [mean age 65.6 yrs]). SPs reported their own mood on the Beck Depression Inventory (BDI) and rated their partners' (the SPTs') mood using the Hamilton Rating Scale for Depression (HRSD). A clinician evaluated the SPTs' mood using the HRSD and their cognitive/language and physical impairments using a battery of neuropsychological tests. Results indicated that 44% of the SPs were depressed. SP depression was not correlated with the severity of the SPTs' physical, cognitive, or language impairments. However, the SPs' perception of the SPTs' mood was a better predictor of the SPs' mood than was the clinicians' evaluation of the SPTs' mood. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Serial assessment of the cardiovascular system in normal pregnancy. Role of arterial compliance and pulsatile arterial load

BACKGROUND: Temporal changes in systemic arterial compliance and wave propagation properties (pulsatile arterial load) and their role in ventricular-systemic arterial coupling during gestation have not been explored. Noninvasive methods combined with recently developed mathematical modeling techniques were used to characterize vascular and left ventricular (LV) mechanical adaptations during normal gestation. METHODS AND RESULTS: Fourteen healthy women were studied at each trimester of pregnancy and again postpartum. Experimental measurements included instantaneous aortic pressure (subclavian pulse tracings) and flow (aortic Doppler velocities) and echocardiographic imaging of the LV. A small increase in LV muscle mass and end-diastolic chamber dimension occurred by late gestation, with no significant alterations in myocardial contractility. Cardiac output increased and the steady component of arterial load (total vascular resistance) decreased during pregnancy. Several changes in pulsatile arterial load were noted: Global arterial compliance increased (approximately 30%) during the first trimester and remained elevated thereafter. The magnitude of peripheral wave reflections at the aorta was reduced. The mathematical model-based analysis revealed that peripheral wave reflections at the aorta were delayed and that both conduit and peripheral vessels contributed to the increased arterial compliance. Finally, coordinated changes in the pulsatile arterial load and LV properties were responsible for maintaining the efficiency of LV-to-arterial system energy transfer. CONCLUSIONS: The rapid time course of compliance changes and the involvement of both conduit and peripheral vessels are consistent with reduced vascular tone as being the main underlying mechanism. The pulsatile arterial load alterations during normal pregnancy are adaptive in that they help to accommodate the increased intravascular volume while maintaining the efficiency of ventricular-arterial coupling and diastolic perfusion pressure.     

Long-chain free fatty acids: Semiochemicals for host location by western corn rootworm larvae

A bioassay-driven sequential fractionation scheme was used to isolate fractions of a crude dichloromethane maize seedling extract behaviorally active to larvae of the western corn rootworm,Diabrotica virgifera virgifera LeConte. (Z,Z)-9,12-Octadecadienoic (linoleic) acid, (Z)-9-octadecenoic (oleic) acid, and octadecanoic (stearic) acid were identified from a purified fraction of maize extract that was attractive to western corn rootworm larvae in choice tests with equal levels of carbon dioxide on both sides of the choice. When synthetic linoleic, oleic, and stearic acids were tested together in the amounts and proportions found in the attractive fraction (1000, 800, and 300 ng of linoleic, oleic, and stearic acids, respectively), significantly more western corn rootworm larvae were found on the side with synthetic free fatty acids plus carbon dioxide than on the side with carbon dioxide alone. Results of the choice-test bioassays were not significantly different when the synthetic blend of free fatty acids was substituted for the purified maize fraction. Neither the purified extract nor the synthetic blend was behaviorally active in preliminary single-choice experiments without carbon dioxide. Linoleic, oleic, and stearic acids were also tested individually in the choice test bioassay with carbon dioxide on both sides of the choice to determine a dose-response curve. Linoleic and oleic acid each had one dose that was significantly attractive in conjunction with carbon dioxide on both sides of the choice, but stearic acid was not active in the doses tested.     

Enantiomeric composition of grandisol and grandisal produced byPissodes strobi andP. nemorensis and their electroantennogram response to pure enantiomers

Grandisol (cis-2-isopropenyl-1-methylcyclobutaneethanol) and its corresponding aldehyde, grandisal, were previously isolated and identified as aggregation pheromone components forPissodes strobi (Peck) andP. nemorensis Germar, but the enantiomeric ratios produced by these insects were not previously determined. We isolated grandisol and grandisal from males of bothP. strobi andP. nemorensis. The insect-produced grandisol was derivatized with trifluoroacetic anhydride, and the enantiomeric composition was determined by gas chromatography on an optically active cyclodextrin glass capillary column. The insect-produced grandisal was first reduced to grandisol before derivatization.P. nemorensis produced nearly 100% (1R,2S)-grandisol and nearly 100% (1S,2R)-grandisal.P. strobi produced 99% (1R,2S)-grandisol and approximately 60% (lR,2S)-grandisal. In electroantennogram (EAG) studies with liveP. nemorensis andP. strobi, no significant differences were found between the responses of males and females to racemic grandisol, racemic grandisal, or the 1R,2S and 1S,2R enantiomers of grandisol and grandisal, which is consistent with previous assertions that these compounds are aggregation pheromones. Although no studies to date withP. strobi have demonstrated a behavioral response to grandisol and grandisal,P. strobi antennae detected all enantiomers of grandisol and grandisal tested in EAG tests. The antennae of P.nemorensis responded significantly more to (1R,2S) grandisal than to (1S,2R)-grandisal, despite producing only (1S,2R)-grandisal.Coleoptera: Curculionidae.     

Reinforcement of microtruss cellular materials by nanocrystalline electrodeposition

Compositionally graded microtruss cellular materials can be created by electrodepositing ultrahigh-strength sleeves of nanocrystalline material over precursor microtruss cores. Due to their position relative to the neutral axis of the struts, even relatively thin coatings can provide significant strength and weight benefits to the precursor assembly. Using nanocrystalline nickel as an example, the questions of strength prediction, performance increase, sleeve/core delamination and sleeve fracture are discussed.