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Holyoke, MA, United States

Okamura M.,Brookhaven National Laboratory | Okamura M.,RIKEN | Adeyemi A.,Holyoke Community College | Kanesue T.,RIKEN | And 6 more authors.
Review of Scientific Instruments | Year: 2010

A laser ion source (LIS) can easily provide a high current beam. However, it has been difficult to obtain a longer beam pulse while keeping a high current. On occasion, longer beam pulses are required by certain applications. For example, more than 10 μs of beam pulse is required for injecting highly charged beams to a large sized synchrotron. To extend beam pulse width, a solenoid field was applied at the drift space of the LIS at Brookhaven National Laboratory. The solenoid field suppressed the diverging angle of the expanding plasma and the beam pulse was widened. Also, it was observed that the plasma state was conserved after passing through a few hundred gauss of the 480 mm length solenoid field. © 2010 American Institute of Physics.

Kahn D.,Harvard University | Gover T.,Holyoke Community College
International Review of Neurobiology | Year: 2010

This chapter argues that dreaming is an important state of consciousness and that it has many features that complement consciousness in the wake state. The chapter discusses consciousness in dreams and how it comes about. It discusses the changes that occur in the neuromodulatory environment and in the neuronal connectivity of the brain as we fall asleep and begin our night journeys. Dreams evolve from internal sources though the dream may look different than any one of these since something entirely new may emerge through self-organizing processes. The chapter also explores characteristics of dreaming consciousness such as acceptance of implausibility and how that might lead to creative insight. Examples of studies, which have shown creativity in dream sleep, are provided to illustrate important characteristics of dreaming consciousness. The chapter also discusses the dream body and how it relates to our consciousness while dreaming. Differences and similarities between wake, lucid, non-lucid and day dreaming are explored and the chapter concludes with a discussion on what we can learn from each of these expressions of consciousness. © 2010 Elsevier Inc.

Wentworth K.L.,Holyoke Community College | Brittingham M.C.,Pennsylvania State University | Wilson A.M.,Pennsylvania State University
Journal of Soil and Water Conservation | Year: 2010

Almost 30,000 ha (74,100 ac) of grassland were created in south-central Pennsylvania through the USDA Conservation Reserve Enhancement Program (CREP) from 2000 to 2004.To assess the use of these fields by grassland and other birds and to develop region-specific management guidelines, we conducted transect counts of singing birds in 103 CREP fields during 2002 to 2004 and measured within-field vegetation and landscape characteristics.Thirty-two bird species were found on fields during the breeding season. Redwinged blackbirds (Agelaius phoeniceus) were most numerous, followed by three shrub-scrub species. Grassland obligate species were rare and were most abundant on larger fields with a lower density of vegetation and a predominance of cool-season grasses. Abundances of shrub-scrub species were highest on smaller fields with a higher density of vegetation and a higher proportion of warm-season grasses. Avian use of CREP fields in Pennsylvania differs from Midwestern Conservation Reserve Program fields in a number of important ways. Shrub-scrub species were more common, which may be due to the small mean field size and the more forested landscape. In addition, grassland obligates were found in greater densi-ties on fields of cool-season grasses than in fields of warm-season or mixed grasses. Targeted enrollment and management of large fields or those adjoining other grasslands for grassland birds and small fields or those adjoining woodlands for shrub-scrub species may be the best approach to maximize the benefits of CREP for a range of bird species.

Eggler D.H.,Pennsylvania State University | Ehmann A.N.,Pennsylvania State University | Ehmann A.N.,Holyoke Community College
American Mineralogist | Year: 2010

A mixture of antigorite, forsterite, and enstatite was reacted at 2 GPa pressure, with water, to study kinetics of the reaction Mg48Si 34O85(OH)62 = 10 Mg2Si 2O6 + 14 Mg2SiO4 + 31 H 2O. Reaction progress, F, which can vary between +1 and -1, was measured by comparing areas under X-ray diffraction peaks for run products with corresponding peaks for the starting material. Rates for dehydration and hydration can be regressed with the equation: r FR/t = K rA°θ[-171{1-Teq/T}]n mol/cmrock3/s The function FR accounts for the decrease in Aθ, specific surface area, from A θ° at F = 0 to 0 at F = 1: FR = 1/1-p [1-(1-F)1-p] where p, ∼0.50 for elongate grains, characterizes grain shape. Regression of the rate equation for dehydration runs can be combined with Aθ°, measured on the antigorite starting material, to give reaction rate Kr: -9.2(l.2) × 10 -15mol/s/cm2. With that rate, we calculate that well-defined conventional reversal brackets of 5 °C around the equilibrium temperature would require run lengths of 729(99) h, considerably longer than in this or any previous study. The rate equations can be applied to the question of overstepping of antigorite dehydration below arcs. One modeled geotherm 40 km below a slab surface crosses the antigorite dehydration reaction at about 2 GPa; the slab takes 3 × 105 years to warm one degree. For grain sizes in a serpentinite in the 0.1 to 10 cm range, complete dehydration would take 104-105 years. During that time, the plate would travel no more than a kilometer past the point of first dehydration. If earthquakes associated with dehydration occurred on timescales of 10 3-104 years, complete dehydration of a volume of plate would require 10-100 separate dehydration events.

Gross D.,University of Massachusetts Amherst | Pietri E.S.,Yale University | Anderson G.,University of Massachusetts Amherst | Moyano-Camihort K.,University of Massachusetts Amherst | And 2 more authors.
CBE Life Sciences Education | Year: 2015

Active-learning environments such as those found in a flipped classroom are known to increase student performance, although how these gains are realized over the course of a semester is less well understood. In an upper-level lecture course designed primarily for biochemistry majors, we examine how students attain improved learning outcomes, as measured by exam scores, when the course is converted to a more active flipped format. The context is a physical chemistry course catering to life science majors in which approximately half of the lecture material is placed online and in-class problem-solving activities are increased, while total class time is reduced. We find that exam performance significantly improves by nearly 12% in the flipped-format course, due in part to students interacting with course material in a more timely and accurate manner. We also find that the positive effects of the flipped class are most pronounced for students with lower grade point averages and for female students. © 2015 D. Gross et al.

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