Interactions between the cholinergic and dopaminergic system during the production of ultrasonic vocalizations in rats

Rats produce ultrasonic vocalizations that can be categorized into two types of ultrasonic calls based on their sonographic structure. One group contains 22-kHz ultrasonic vocalization (USVs), characterized by relatively constant (flat) frequency with peak frequency ranging from 19 to 28-kHz, and a call duration ranging between 100 – 3000 ms. These vocalization can be induced by cholinomimetic agents injected into the ascending mesolimbic cholinergic system that terminates in the anterior hypothalamic-preoptic area (AH-MPO) and lateral septum (LS). The other group of USVs contains 50-kHz USVs, characterized by high peak frequency, ranging from 39 to 90-kHz, short duration ranging from 10-90 ms, and varying frequency and complex sonographic morphology. These vocalizations can be induced by dopaminergic agents injected into the nucleus accumbens, the target area for the mesolimbic dopaminergic system. 22-kHz USVs are emitted in situations that are highly aversive, such as proximity of a predator or anticipation of a foot shock, while 50 kHz USVs are emitted in rewarding and appetitive situations, such as juvenile play behaviour or anticipation of rewarding electrical brain stimulation. The activities of these two mesolimbic systems were postulated to be antagonistic to each other. The current thesis is focused on the interaction of these systems indexed by emission of relevant USVs. It was hypothesized that emission of 22 kHz USVs will be antagonized by prior activation of the dopaminergic system while emission of 50 kHz will be antagonized by prior activation of the cholinergic system. It was found that injection of apomorphine into the shell of the nucleus accumbens significantly decreased the number of carbachol-induced 22 kHz USVs from both AH-MPO and LS. Injection of carbachol into the LS significantly decreased the number of apomorphine-induced 50 kHz USVs from the shell of the nucleus accumbens. The results of the study supported the main hypotheses that the mesolimbic dopaminergic and cholinergic systems function in antagonism to each other.

CENTRAL NORTH ATLANTIC PALEOCEANOGRAPHY DURING THE MIDDLE PLEISTOCENE (ca. 726–603 ka): INSIGHTS FROM THE DINOFLAGELLATE CYST RECORD

Integrated Ocean Drilling Program (IODP) Site U1313, located at the northern boundary of the subtropical gyre in the central North Atlantic, lies within the southern part of the ice-rafted debris belt. Seventy-three palynological samples were studied from an uninterrupted interval ca. 726–603 ka (upper Marine Isotope Stage [MIS] 18 through lower MIS 15) to resolve conflicting paleoceanographic interpretations. Glacial stages were characterized by high productivity surface waters reflecting a southward shift of the Arctic Front. Sea surface salinities (SSSs) and sea surface temperatures (SSTs) were obtained by transfer functions using the Modern Analogue Technique. The lowest SSTs of 9ºC (±1.3) and 10ºC (±1.3) were recorded in glacial MIS 16 and MIS 18 respectively. However, these reconstructions are influenced by abundant heterotrophic taxa and may reflect elevated nutrient levels rather than lowered temperatures. Reworked palynomorphs uniquely indicate a Cretaceous as well as Paleozoic provenance for the first Heinrich-like events.

Canadian Military Institute: Officers of the British Forces in Canada during the War of 1812-1815

There is a note in the front cover written to Mary from B. Johnston on April 22, 1942. He refers to page 73 of the book in which William Woodruff is listed as a Lieutenant and Richard Woodruff is listed as an Ensign in the Niagara District. A full text version is available at the following link: http://www.archive.org/details/officersbritish00instgoog

Examining peer-controlled KR schedules during the learning of a movement-timing task as a function of task experience.

Learners can be provided with feedback in the form of knowledge of results (KR), under self-controlled and peer-controlled schedules. Recently, McRae, Hansen, and Patterson (2015), identified that inexperienced peers can provide KR that can facilitate motor skill acquisition. However, it is currently unknown whether previous task experience differentially impacts how peers present learners with KR and whether this KR impacts motor skill acquisition. In the present study, participants were randomly assigned to become inexperienced peer facilitators, learners with an inexperienced peer, learners with self-control who later became experienced peers, learners with an experienced peer, or learners in a control group. During acquisition learners completed a serial-timing task with a goal of 2500ms and returned approximately twenty four hours later for a delayed retention, time transfer, and pattern transfer test. We predicted that during the delayed tests, learners with self-control would outperform all other groups. Furthermore, we predicted that learners who received KR from experienced peers would outperform learners who received KR from inexperienced peers. However, our results indicated that participants who received peer-controlled and self-controlled KR schedules learned the task in an equivalent manner. Thus, our results are novel as they identify that inexperienced peers can provide KR that is as effective as KR provided by experienced peers and KR requested under self-controlled conditions.

Chart of estimate #7 of work done by John Williams during the month of May. This is signed by Fred Holmes, May 29, 1856

Chart of estimate #7 of work done by John Williams during the month of May. This is signed by Fred Holmes, May 29, 1856.

Chart of estimate #8 of work done by John Williams during the month of June

Chart of estimate #8 of work done by John Williams during the month of June. This is signed by Fred Holmes, June 1856

Note regarding the number of days Fred Holmes was employed upon the Port Robinson and Thorold macadamized road during the months of July and August

Note regarding the number of days Fred Holmes was employed upon the Port Robinson and Thorold macadamized road during the months of July and August. This is signed by S.D. Woodruff and Fred Holmes, November, 1857.

Estimate for Fred Holmes and William Baird for time on the Port Robinson and Thorold Macadamized Road during the months of September, October and November, 1856

Estimate for Fred Holmes and William Baird for time on the Port Robinson and Thorold Macadamized Road during the months of September, October and November, 1856. This was sent to S.D. Woodruff by Fred Holmes, Nov.29, 1856.

Estimate of work done by A. Cook on the marsh lands main drain during the month of June 1857

Estimate of work done by A. Cook on the marsh lands main drain during the month of June 1857. This is signed by Fred Holmes, June 30, 1857.

Estimate for A. Cook for the excavation of the marsh lands main drain during the month of July for A. Cook and Rose Osborne

Estimate for A. Cook for the excavation of the marsh lands main drain during the month of July for A. Cook and Rose Osborne. This was sent to S.D. Woodruff by Fred Holmes, July 27, 1857.

General return (copy) showing the quantity of each article transported on the Welland Canal during the year ending January 5th 1857 (Port Robinson)

General return (copy) showing the quantity of each article transported on the Welland Canal during the year ending January 5th 1857 (Port Robinson) (2 pages), 1857.

General return showing the quantity of each article transported on the Welland Canal during the year ending 1857 and the amount of tolls collected thereon (Port of Maitland)

General return showing the quantity of each article transported on the Welland Canal during the year ending 1857 and the amount of tolls collected thereon (Port of Maitland) (2 page, printed blank), 1857.

General return showing the quantity of each article transported on the Welland Canal during the year ending December 31st, 1858

General return showing the quantity of each article transported on the Welland Canal during the year ending December 31st, 1858 and the amount of tolls collected thereon (Port of Maitland). This is signed by William Turner, collector (2 page, printed blank), 1858.

General return showing the quantity of each article transported on the Welland Canal during the year ending on the 31st of December 1858

General return showing the quantity of each article transported on the Welland Canal during the year ending on the 31st of December 1858 and the tolls collected thereon (office at Port Robinson) (2 pages), 1858.

General return showing the quantity of each article transported on the Welland Canal during the year ending the 31st of December 1860 and the amount of tolls collected thereon

General return showing the quantity of each article transported on the Welland Canal during the year ending the 31st of December 1860 and the amount of tolls collected thereon. This document was mouldy (now inactive). This does not affect the text. It is signed by William Turner, collector (office at Port Maitland), 1860.