13,271 research outputs found
Duration discrimination of brief visual stimuli
Visual flash duration discrimination and decision theory analysis of effects of temporal and brightness difference
Duration discrimination of brief visual off-flashes
Visual flash duration discrimination and analysis of temporal and energy cue models, and memory effect
Brood diseases of bee
American foul brood (AFB) also know as American brood disease (ABD) is an infectious disease of honey bees cause by bacteria, Bacillus larvae. This bacteria forms spores which will survive many years in the environment and the bee larvae become infected by swallowing the spores with teir food. The spores then develop and multiply within the larvae.https://researchlibrary.agric.wa.gov.au/bulletins/1253/thumbnail.jp
Comment on "Quantum Confinement and Optical Gaps in Si Nanocrystals"
We show that the method used by Ogut, Chelikowsky and Louie (Phys. Rev. Lett.
79, 1770 (1997)) to calculate the optical gap of Si nanocrystals omits an
electron-hole polarization energy. When this contribution is taken into
account, the corrected optical gap is in excellent agreement with
semi-empirical pseudopotential calculations.Comment: 3 pages, 1 figur
Quahogs in Eastern North America: Part II, History by Province and State
The northern quahog, Mercenaria mercenaria, ranges along the
Atlantic Coast of North America from the Canadian Maritimes to Florida, while the southern quahog, M. campechiensis,
ranges mostly from Florida to southern Mexico. The northern quahog was fished by native North Americans during prehistoric periods. They used the meats as food and the shells as scrapers and as utensils. The European colonists copied the Indians treading method, and they also used short
rakes for harvesting quahogs. The Indians of southern New England and Long Island, N.Y., made wampum from quahog shells, used it for ornaments and sold it to the colonists, who, in turn, traded it to other Indians for furs. During the late 1600’s, 1700’s, and 1800’s, wampum was made in small factories for eventual trading with Indians farther west for furs.
The quahoging industry has provided people in many coastal communities with a means of earning a livelihood and has
given consumers a tasty, wholesome food whether eaten raw, steamed, cooked in chowders, or as stuffed quahogs. More than a dozen methods and types of gear have been used in the last two centuries for harvesting quahogs. They include treading and using various types of rakes and dredges,
both of which have undergone continuous improvements in design. Modern dredges are equipped with hydraulic jets and one type has an escalator to bring the quahogs continuously to the boats. In the early 1900’s, most provinces and states
established regulations to conserve and maximize yields of their quahog stocks. They include a minimum size, now almost
universally a 38-mm shell width, and can include gear limitations and daily quotas.
The United States produces far more quahogs than either Canada or Mexico. The leading producer in Canada is Prince
Edward Island. In the United States, New York, New Jersey, and Rhode Island lead in quahog production in the north, while Virginia and North Carolina lead in the south. Connecticut and Florida were large producers in the 1990’s. The State of Tabasco leads in Mexican production. In the northeastern United States, the bays with large openings, and thus large exchanges of bay waters with ocean waters,
have much larger stocks of quahogs and fisheries than bays with small openings and water exchanges.
Quahog stocks in certified beds have been enhanced by transplanting stocks to them from stocks in uncertified waters and by planting seed grown in hatcheries, which grew in number from Massachusetts to Florida in the 1980’s and 1990’s
Non-local nuclear spin quieting in quantum dot molecules: Optically-induced extended two-electron spin coherence time
We demonstrate the extension of coherence between all four two-electron spin
ground states of an InAs quantum dot molecule (QDM) via non-local suppression
of nuclear spin fluctuations in both constituent quantum dots (QDs), while
optically addressing only the upper QD transitions. Long coherence times are
revealed through dark-state spectroscopy as resulting from nuclear spin locking
mediated by the exchange interaction between the QDs. Lineshape analysis
provides the first measurement of the quieting of the Overhauser field
distribution correlating with reduced nuclear spin fluctuations.Comment: Supplementary materials can be found on the publication page of our
website. http://research.physics.lsa.umich.edu/dst/Publications.htm
Frequency-dependent spontaneous emission rate from CdSe and CdTe nanocrystals: influence of dark states
We studied the rate of spontaneous emission from colloidal CdSe and CdTe
nanocrystals at room temperature. The decay rate, obtained from luminescence
decay curves, increases with the emission frequency in a supra-linear way. This
dependence is explained by the thermal occupation of dark exciton states at
room temperature, giving rise to a strong attenuation of the rate of emission.
The supra-linear dependence is in agreement with the results of tight-binding
calculations.Comment: 11 page
Problem-based Learning in Institutional and Curricular Design at the New Model Institute for Technology and Engineering (NMITE)
NMITE’s Master’s in Integrated Engineering (MEng) was created with a unique philosophy of integrating not only traditionally separate strands of engineering, but also of integrating engineering with other disciplines such as arts, humanities, and business. This broad and deep integration is made possible by adopting the principles and practices of problem-based learning (PBL) and embedding them within predetermined module challenges. In this way, each PBL challenge highlights and hones areas of engineering expertise and embeds liberal subjects whilst maintaining the integration intrinsic to the programme. Overall, this method supports the use of block learning with deep integration of employers and the community in the educational experience
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