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2003

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Fluid Flow In Oscillating Cavities, Srivathsan Ragunathan Dec 2003

Fluid Flow In Oscillating Cavities, Srivathsan Ragunathan

Engineering

Oscillatory flows have gained considerable research attention in the recent decades following an interest in transport enhancement in micro-electronic devices. Heat transfer enhancement due to flow modulation has an inherent advantage over conventional mechanical heat transfer components in terms of reduction in weight and space. The present work is aimed at studying fluid flow in oscillating square cavities as a first step towards heat transfer enhancement. A commercial CFD code, Fluent, was used to model a test case consisting of Stokes' second problem, with a source code written in the C programming language. The simulated results were in good agreement …

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Water Quality From Rainwater Catchments Throughout Alaska: Looking At Contaminants In Catchment Materials, Corianne Irene Hart Dec 2003

Water Quality From Rainwater Catchments Throughout Alaska: Looking At Contaminants In Catchment Materials, Corianne Irene Hart

Engineering

A field study which focused on linking materials used in rainwater catchments to the quality of water they produce was conducted throughout Alaska in the summer of 2003. The importance of this project stems from the fact that many families throughout Alaska depend on rainwater catchment systems to provide water for washing, cleaning, cooking and/or drinking purposes. After a core group of participants were identified, samples were periodically collected from participants' water taps and were analyzed for a suite of contaminants that included metals (e.g., Pb and Zn), organics (e.g., volatile organic compounds) and bacteria. Based on variables, such as …

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The 1931 Eruption Of Aniakchak Volcano, Alaska: Deposit Characteristics And Eruption Dynamics, Robert Stokes Nicholson Dec 2003

The 1931 Eruption Of Aniakchak Volcano, Alaska: Deposit Characteristics And Eruption Dynamics, Robert Stokes Nicholson

Geosciences

The 1931 eruption of Aniakchak progressed through several eruptive phases from multiple vents that totaled 1.4 x 10⁸ m³ dense rock equivalent of magma. The sequence of phases began with a sub-plinian eruption followed by a phreatomagmatically-influenced vulcanian phase originating from the primary vent. Effusive activity from two separate vents occurred simultaneously with the vulcanian phase. The eruption from the main vent progressed to strombolian in nature and eventually subsided into an effusive eruption. The composition of the magma ranged from trachydacite at the onset of the eruption to basaltic andesite at its conclusion. Volcanoes commonly exhibit variations in eruptive …

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A Place For The Birds: The Legacy Of Creamer's Field Migratory Waterfowl Refuge, Jessica A. Ryan Dec 2003

A Place For The Birds: The Legacy Of Creamer's Field Migratory Waterfowl Refuge, Jessica A. Ryan

Arctic and Northern Studies

This thesis details the farming history and current importance of the Creamer's Field Migratory Waterfowl Refuge in Fairbanks, Alaska. More significantly, it is the story of a grassroots effort by the community of Fairbanks, working with a kindly old farmer, to preserve open land in the heart of a rapidly expanding city for the benefit of the thousands of migrating cranes, geese and ducks that rely upon the grain fields each spring and fall. Because of their vision, Creamer's Field has become a center for environmental education, outdoor recreation, and biological research while actively providing for the needs of wildlife.

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An In Vitro Analysis Of Neuronal Survival In Response To Hormones And Photoperiod In The Hvc Of The Songbird Junco Hyemalis, Catherine Martin Humphries Dec 2003

An In Vitro Analysis Of Neuronal Survival In Response To Hormones And Photoperiod In The Hvc Of The Songbird Junco Hyemalis, Catherine Martin Humphries

Chemistry and Biochemistry

The ability of songbirds to sing is essential for their survival, proper reproductive behavior, and territorial establishment. Male and female juvenile passerine songbirds learn their song through the formation of a song template in their earliest days of life, first by listening to their parents, and then followed by auditory feedback against their own templates to crystallize their individual songs. However, in most passerine species, only the adult males actually sing on a seasonal basis with little to no singing during winter, followed by a phase of song production in the spring in correlation with increased plasma testosterone concentration and …

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Chemical And Mass Spectral Studies Of 2,2-Dialkylglycine Decarboxylase, Julie Ann La Rocca-Brigham Dec 2003

Chemical And Mass Spectral Studies Of 2,2-Dialkylglycine Decarboxylase, Julie Ann La Rocca-Brigham

Chemistry and Biochemistry

2,2-Dialkylglycine Decarboxylase, DGD, is a decarboxylating transaminase that is dependent on a vitamin B6 cofactor, pyridoxal 5'-phosphate (PLP). DGD catalyzes the decomposition of 2-methylalanine in two steps. DGD was purified by ammonium sulfate precipitation and ion-exchange chromatography. The enzyme was reduced to form a covalent bond between the enzyme and the PLP. Also, [alpha]-(Trifluoromethyl) Alanine, a suicide mechanism based inhibitor was reacted with DGD until the enzyme was completely inactivated. The nonmodified DGD and these two modified forms of the enzyme were subjected to enzymatic digestion by trypsin. Finally, all three peptide mixtures were analyzed by LC/MS/MS. The mass spectra …

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Human Impacts To Fire Regime In Interior Alaska, La'ona Dewilde Dec 2003

Human Impacts To Fire Regime In Interior Alaska, La'ona Dewilde

Biological Sciences

A thorough analysis of human impacts on interior Alaska's fire regime demonstrates that human activities have effects in populated areas. Two approaches were used to determine impacts: I examined three regions with very different populations, and also one large region to analyze suppression, ignition, and vegetation interactions. The Fairbanks Region, with a large human population and an extensive road system, differs from two other regions with low human populations and few roads. In the Fairbanks Region, humans have impacted fire regime by causing more fires in certain fuel types and doubling the length of the fire season. The Fairbanks Region, …

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Timing Of Breeding And Reproductive Success In A Subarctic Population Of Yellow Warblers (Dendroica Petechia), Kristine Marie Sowl Dec 2003

Timing Of Breeding And Reproductive Success In A Subarctic Population Of Yellow Warblers (Dendroica Petechia), Kristine Marie Sowl

Biological Sciences

Detailed knowledge of reproductive rates is necessary for understanding population dynamics, but this information is lacking for many populations of migratory songbirds. I examined breeding chronology and reproductive success of Yellow Warblers (Dendroica petechia) breeding in east central Alaska in 1997-2000. Yellow Warblers nested in both spruce forest and willow shrub habitats, but breeding density and nest success were greater in shrub habitat. Annual productivity was influenced by the number of breeding attempts per female, clutch size, success of individual eggs or nestlings, and nest success. Mean clutch size was larger than in lower latitude populations and decreased seasonally. The …

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The Role Of Mammalian Herbivores In Primary Succession On The Tanana River Floodplain, Interior Alaska, Lemuel Gordon Butler Dec 2003

The Role Of Mammalian Herbivores In Primary Succession On The Tanana River Floodplain, Interior Alaska, Lemuel Gordon Butler

Biological Sciences

I compared willow (Salix) communities along the Tanana River exposed to varying levels of herbivory to examine how herbivory influences the landscape distribution of vegetation. Moose (Alces alces) and snowshoe hare (Lepus americanus) herbivory decreased plant biomass and canopy height and increased the proportion of dead stems in willow communities. Herbivory also shifted the age distribution of plants in willow communities towards younger age classes, and also decreased the number of communities dominated by willow on the landscape. A frame-based simulation model was built to incorporate the effects of herbivory and river fluvial dynamics on plant succession. My results show …

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Northeast Research Station Watertown, South Dakota Annual Progress Report, 2003, Agricultural Experiment Station, Plant Science Department Dec 2003

Northeast Research Station Watertown, South Dakota Annual Progress Report, 2003, Agricultural Experiment Station, Plant Science Department

Agricultural Experiment Station and Research Farm Annual Reports

This is the 2003 annual progress report for the Northeast Research Station in Watertown, South Dakota. This report is issued by the South Dakota Agricultural Experiment Station and the South Dakota State University Plant Science Department. This report includes weather data, yield comparisons, crop performance trials, corn trials, soybean trials, winter wheat performance testing, Barley Foliar information, weed and pest control, herbicide demonstrations, canola and flax variety trials and more.

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Two Unh Fraternities Found, Kim Billings Dec 2003

Two Unh Fraternities Found, Kim Billings

Media Relations

No abstract provided.

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Annual Flower Evaluations 2003, Patricia S. Holloway, Grant E. Matheke, Jan Hanscom, Alfreda Gardiner, Victoria Hill, Eileen Van Wyhe Dec 2003

Annual Flower Evaluations 2003, Patricia S. Holloway, Grant E. Matheke, Jan Hanscom, Alfreda Gardiner, Victoria Hill, Eileen Van Wyhe

Circulars

No abstract provided.

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Cultural Activity And Market Enterprise: A Circumpolar Comparison Of Reindeer Herding Communities At The End Of The 20th Century, Michael Stephen Koskey Dec 2003

Cultural Activity And Market Enterprise: A Circumpolar Comparison Of Reindeer Herding Communities At The End Of The 20th Century, Michael Stephen Koskey

Anthropology

Reindeer herding throughout the circumpolar North is in decline. Investigating this decline, this dissertation takes a comparative approach with a focus on four case studies: the Chukchi of Chukotskii Peninsula, the Iñupiat of the Seward Peninsula, the Saami of the Kola Peninsula, and the Saami of Finnmark. Because various rates and types of decline are occurring in these different cases, a comparative method leads to a systematic analysis of how patterns develop in the practice of contemporary reindeer herding, both locally and globally. Comparing and contrasting the trajectories of declines in reindeer herding identifies and explains the dimensions of specific …

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Stock Structure And Environmental Effects On Year Class Formation And Population Trends Of Pacific Herring, Clupea Pallasi, In Prince William Sound, Alaska, Evelyn D. Brown Dec 2003

Stock Structure And Environmental Effects On Year Class Formation And Population Trends Of Pacific Herring, Clupea Pallasi, In Prince William Sound, Alaska, Evelyn D. Brown

Fisheries

Fluctuating forage fish populations trigger large ecosystem responses in the North Pacific. A representative species, Pacific herring, Clupea pallasi, was chosen to model environmental effects on population fluctuations and recruitment with a case example in Prince William Sound (PWS), Alaska. A unique approach was used to 1) develop a spatially-explicit, life history-based conceptual stock model, 2) quantify population level effects of climatic trends, and 3) model key environmental factors affecting recruitment. Framed as a simulation model, the stock model was compartmentalized by life-history stages based on shared habitats and environmental forcing. Initial model conditions impacting year-class formation were adult size-at-age, …

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Movement And Habitat Utilization By Golden King Crab Lithodes Aequispinus Benedict 1895 In Southeastern Alaska, Zachary N. Hoyt Dec 2003

Movement And Habitat Utilization By Golden King Crab Lithodes Aequispinus Benedict 1895 In Southeastern Alaska, Zachary N. Hoyt

Fisheries

Movements and habitat use of golden king crabs (GKC), Lithodes aequispinus, were investigated with a manned submersible and ultrasonic telemetry in Frederick Sound, Alaska. Crabs were collected with commercial crab pots and ultrasonic transmitters were attached to the carapaces of 26 crabs; movements and depth distribution of male and female crabs were monitored bi- monthly from May 11, 2000 to April 12, 2001. Crabs preferred steep, complex habitat with hard substrate; few were on flat, soft substrate. Male and female GKC were not segregated by depth in mid-May. Seventeen pairs of courting crabs were observed during dives; 14 of these …

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Growth Dynamics Of Juvenile Yellowfin Sole (Pleuronectes Asper) And Northern Rock Sole (Lepidopsetta Polyxystra) In The Eastern Bering Sea, Benjamin Charles Williams Dec 2003

Growth Dynamics Of Juvenile Yellowfin Sole (Pleuronectes Asper) And Northern Rock Sole (Lepidopsetta Polyxystra) In The Eastern Bering Sea, Benjamin Charles Williams

Fisheries

The first five growth zones of 744 yellowfin sole and 512 northern rock sole otoliths were measured from year-classes 1974-1989, to identify patterns of annual growth and sources of temporal variation. Growth patterns were observed graphically and temporal variation was examined by partitioning growth into year and age effects via linear models. Growth and recruitment relationships with biological and environmental variables were explored through correlation analysis and stepwise regression. Results indicate that growth of yellowfin sole and rock sole declined from the late 1970s to the mid 1980s. Yellowfin sole length at age rebounded after 1985, while rock sole length …

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Investigation And Development Of A Mathematical Model For The Oxidation Of Cyanide In The Inco So₂/O₂ Process, James L. Oleson Dec 2003

Investigation And Development Of A Mathematical Model For The Oxidation Of Cyanide In The Inco So₂/O₂ Process, James L. Oleson

Engineering

The purpose of this study was to develop a mathematical model to describe the oxidation of cyanide with SO₂ as proposed in the INCO process. This research employed a direct method for measuring the change in cyanide concentration with respect to time as affected by varying concentrations of SO₂ and copper and pH. This model may be applicable in determining optimum conditions in a process well known and used in the mining industry.

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Post-Caldera Eruptions At Okmok Volcano, Umnak Island, Alaska, With Emphasis On Recent Eruptions From Cone A, Delenora M. Grey Dec 2003

Post-Caldera Eruptions At Okmok Volcano, Umnak Island, Alaska, With Emphasis On Recent Eruptions From Cone A, Delenora M. Grey

Geosciences

Okmok volcano has undergone two caldera-forming eruptions, 12,000 and 2050 BP, and has been quite active in historic time. The historic eruptive record has been compiled and augmented with descriptions and photographs of recent eruptions. Eruptions in 1958 and 1997 produced the first post-caldera lava flows to traverse most of the caldera floor. The source of these flows, Cone A, has been constructed largely during the 20th century. Major element analysis of lavas from eight major intracaldera cones reveals two chemically and spatially separate trends, which suggest two separate magma sources beneath the caldera, one feeding an arc of cones …

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Hydrovolcanism In Okmok Caldera, Alaska, Leslie Deanne Almberg Dec 2003

Hydrovolcanism In Okmok Caldera, Alaska, Leslie Deanne Almberg

Geosciences

Hydrovolcanic activity in Okmok Caldera predominated on the crater floor during approximately the first 775 years after the caldera collapsed at 2050 yr. B.P. Interactions between rising magma and shallow water (<100 m) controlled the development of lithofacies observed in the early post-caldera deposits. The distinctive lithofacies reflect the eruptive processes active as Cone D, a composite tuff, lava flow, and cinder cone, breached the surface of a lake which once covered the caldera floor. Three phases of eruptive activity constructed Cone D: first, a subaqueous cycle; second, emergent; and finally a purely subaerial strombolian and hawaiian phase built the edifice to its current height. Radiocarbon dates provide constraining ages for a catastrophic flood that emptied the 4.3 x 10⁹ m³ caldera lake and exposed the subaqueous lithofacies. An effusion rate of 2.7 x 10⁶ m³yr⁻¹ for this early eruptive period is calculated using eruptive volumes determined from a 5-m resolution DEM, based on AirSAR data. The prehistoric effusion rate determined for Cone D is on the same order of magnitude as the calculated historic effusion rate of 5.3 x 10⁶ m³yr⁻¹ from Cone A, based on mapped extents and thicknesses of lava flows and the cone itself.

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The Limitations Of Service Members' Constitutional Rights, Dene Ray Leonard Dec 2003

The Limitations Of Service Members' Constitutional Rights, Dene Ray Leonard

Justice

This thesis reviews the constitutional rights of service members and how they are limited by the military. These affected rights include the First Amendment's rights to free speech, religious exercise and the ability to petition the government for redress of grievances; the Fifth Amendment's due process clause; and the Sixth Amendment's right to a jury of one's peers. The discussion section of this thesis argues two justifications used by the military for limiting service members' rights. The first justification is in support of good order, discipline and morale. The second justification is in support of uniformity. The latter discussion also …

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Seasonal Abundance And Diversity Of Nearshore Fishes Around Steller Sea Lion Haulouts Of Kodiak Island, Catherine L. Hegwer Dec 2003

Seasonal Abundance And Diversity Of Nearshore Fishes Around Steller Sea Lion Haulouts Of Kodiak Island, Catherine L. Hegwer

Marine Biology

Nearshore fishes around haulouts are potential prey for Steller sea lions, especially pups, as they learn to forage and supplement their milk diets during weaning. Visual surveys in July and November 2001, and March, May and July 2002 were used to quantify spatial and temporal variation in fish diversity and abundance around two Steller haulouts and two control sites. SCUBA divers sampled depths of 9, 15, 21, 27, and 33 m. Concurrent habitat surveys were used to quantify substrate, macroalga and benthic invertebrate cover. Steller haulout sites had fewer fish than control sites, but similar species richness and species composition …

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Effects Of Areas Closed To Bottom Trawling On Fish And Invertebrate Species In The Eastern Bering Sea, Christine Ann Frazier Dec 2003

Effects Of Areas Closed To Bottom Trawling On Fish And Invertebrate Species In The Eastern Bering Sea, Christine Ann Frazier

Marine Biology

The Bering Sea is a productive ecosystem with some of the most important fisheries in the United States. Constant commercial fishing for groundfish has occurred since the 1960s. The implementation of areas closed to bottom trawling to protect critical habitat for fish or crabs resulted in successful management of these fisheries. The efficacy of these closures on non-target species is unknown. This study determined if differences in abundance, biomass, diversity and evenness of dominant fish and invertebrate species occur among areas open and closed to bottom trawling in the eastern Bering Sea between 1996 and 2000. This study represented four …

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Factors Affecting Estuarine Populations Of Nereocystis Luetkeana In Kachemak Bay, Alaska, HéLoïSe Anne Chenelot Dec 2003

Factors Affecting Estuarine Populations Of Nereocystis Luetkeana In Kachemak Bay, Alaska, HéLoïSe Anne Chenelot

Marine Biology

Nereocystis luetkeana forms extensive kelp beds in Kachemak Bay, Alaska. Salinity and turbidity gradients apparently regulate kelp bed distribution throughout this estuary. The beds are large at the entrance of the bay, only solitary stands occur in the inner bay, and no kelp is found at the head of the bay. The role of salinity and turbidity on Nereocystis sporophyte growth was investigated by performing reciprocal transplants among three beds along the bay axis and regularly measuring stipe growth. The effects of salinity and light on spores were studied in the laboratory by recording sinking tendency, settlement success, germination success, …

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Barents Sea Hydrographic Variability (1975-1991), Sarah Lukens Zimmermann Dec 2003

Barents Sea Hydrographic Variability (1975-1991), Sarah Lukens Zimmermann

Marine Biology

Barents Sea temperature and salinity anomalies and their connection to the Arctic Oscillation (AO) are analyzed using a 16-year time-series of hydrographic data (1975-1991). Seasonal and inter-annual variations are investigated along two sections spanning the meridional and zonal length of the Barents Sea over two depth layers, 0 to 50m and 50 to 200m. Depending on location, mean seasonal differences in the deeper layer are as large as 3°C in temperature and 0.2 in salinity, whereas the upper layer differences are 6°C and 1.4. Inter-annual anomalies are 0.6°C and 0.07 in the deeper layer and 0.8⁰C and 1.2 in the …

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Water Policy Task Force Proposed Recommendations, J. David Aiken Dec 2003

Water Policy Task Force Proposed Recommendations, J. David Aiken

Cornhusker Economics

LB1003, establishing the Nebraska Water Policy Task Force, was signed by Governor Johanns on April 12, 2002. The task force was established to consider (1) changes to LB108, the law dealing with Department of Natural Resources (DNR) and Natural Resources District (NRD) regulations to deal with conflicts between surface water users and groundwater users, and (2) authorizing the buying and selling of water rights, including water leasing and water banking. The task force was initially designed to consider changes in Nebraska water law necessary to allow Nebraska to meet its responsibilities to help protect Platte River endangered species under the …

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Inside The Nh Primary Race 12/17/2003, Unh Survey Center Dec 2003

Inside The Nh Primary Race 12/17/2003, Unh Survey Center

All UNH Survey Center Polls

Howard Dean running away from the field in New Hampshire because he is in tune with the electorate and is viewed more favorably by the electorate. Election: NH Primary 2004

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Manufacturing Of Novel Continuous Nanocrystalline Ceramic Nanofibers With Superior Mechanical Properties, Yuris A. Dzenis, Ruqiang Feng, Gustavo F. Larsen, Joseph Turner, Xiao Cheng Zeng Dec 2003

Manufacturing Of Novel Continuous Nanocrystalline Ceramic Nanofibers With Superior Mechanical Properties, Yuris A. Dzenis, Ruqiang Feng, Gustavo F. Larsen, Joseph Turner, Xiao Cheng Zeng

Papers in Nanotechnology

This project is in the area of nanomanufacturing of advanced nanostructured materials. Nanostructured materials (NSMs) with unusual and extreme properties will play a key role in many emerging technologies. However, manufacturing of NSMs with the desired properties is highly complex and currently is over-reliant on empirical data. In this project, a novel manufacturing process producing a new class of ceramic materials, i.e. continuous ceramic nanofibers, is addressed. The novel sol-gel electrospinning technique (patents pending), invented recently by two of the PI’s (Dzenis and Larsen), produces ceramic fibers of submicron diameters with potentially extreme thermomechanical properties. This technique is being analyzed …

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Assembly Of Α4Β2 Nicotinic Acetylcholine Receptors Assessed With Functional Fluorescently Labeled Subunits: Effects Of Localization, Trafficking, And Nicotine-Induced Upregulation In Clonal Mammalian Cells And In Cultured Midbrain Neurons, Raad Nashmi, Mary E. Dickinson, Sheri Mckinney, Mark Jareb, Cesar Labarca, Scott E. Fraser E. Fraser, Henry A. Lester Dec 2003

Assembly Of Α4Β2 Nicotinic Acetylcholine Receptors Assessed With Functional Fluorescently Labeled Subunits: Effects Of Localization, Trafficking, And Nicotine-Induced Upregulation In Clonal Mammalian Cells And In Cultured Midbrain Neurons, Raad Nashmi, Mary E. Dickinson, Sheri Mckinney, Mark Jareb, Cesar Labarca, Scott E. Fraser E. Fraser, Henry A. Lester

Biology Faculty Publications

Fura-2 recording of Ca2+ influx was used to show that incubation in 1 μM nicotine (2–6d) upregulates several pharmacological components of acetylcholine (ACh) responses in ventral midbrain cultures, including a MLA-resistant, DHβE-sensitive component that presumably corresponds to α4β2 receptors. To study changes in α4β2 receptor levels and assembly during this upregulation, we incorporated yellow and cyan fluorescent proteins (YFPs and CFPs) into the α4 or β2 M3–M4 intracellular loops, and these subunits were coexpressed in human embryonic kidney (HEK) 293T cells and cultured ventral midbrain neurons. The fluorescent …

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Meeting Notes 2003-12-17 [Part B] , Joint Policy Advisory Committee On Transportation Dec 2003

Meeting Notes 2003-12-17 [Part B] , Joint Policy Advisory Committee On Transportation

Joint Policy Advisory Committee on Transportation

No abstract provided.

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Meeting Notes 2003-12-17 [Part A] , Joint Policy Advisory Committee On Transportation Dec 2003

Meeting Notes 2003-12-17 [Part A] , Joint Policy Advisory Committee On Transportation

Joint Policy Advisory Committee on Transportation

No abstract provided.

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