Pushing Off

Women's eight getting ready to push off form the dock.

Sexual behavior and factors affecting female reproduction in house and field crickets

The objective of this investigation was to clarify the adaptive significance of female sexual behaviours in the house cricket, Acheta domesticus, and the Texas field cricket, Gryllus integer. Experiments were focussed primarily on: nutritional factors affecting female reproductive success; the ontogeny of female sexual behaviours; female mating frequency and progeny production; and the pattern of sperm competition. Reproduction of singly mated female A. domesticus assigned to 3 nutritional regimes was compared . Females fed a vitamin and protein-enriched mouse chow, cannibalistic females, and starved females produced on the average, 513 , 200 and 68 offspring, respectively. Cannibals probably could not obtain the same amounts of essential nutrients as females fed mouse chow. Reabsorption of oocytes was likely the major factor contributing to the decreased reproduction of starved females. In addition, female !. domesticus fed mouse chow, but allowed constant access to males produced 11 times as many offspring than did females fed corn meal. Females fed corn meal probably could not absorb or synthesize enough dietary lipids, thus resulting in poor ovariole growth. Female !. domesticus first mate at an average adult age of 7 days, closely corresponding to when they first exhibit positive phonotaxis. Females mate repeatedly and often consume the externally attached spermatophore. In ~. domesticus, females allowed constant access to males produced significantly more offspring than did single maters. Similarly, doubly mated G. integer females produced more offspring than did single maters. This difference resulted largely from the failure of many single maters to reproduce. Remating by female crickets partly functions in offsetting the possibility of a failed initial mating. Nymph production increased significantly with the time the spermatophore was attached in singly mated ~. domesticus. Spermatophore consumption by the female was not affected by male guarding behaviour, and the interval between mating and eating of the spermatophore may often be shorter than the time required for maximum insemination. Some degree of sperm depletion in singly mated !. domesticus and G. integer may have occurred. The patterns of daily offspring production of singly and multiplymated females suggests that a factor provided by a male during mating stimulates female oviposition and/or egg production. Female crickets also might acquire nutrition from spermatophore consumption, a benefit that is augmented by female multiple mating. The electrophoretic examination of various allozymes in ~. integer did not permit determination of a pattern of sperm competition. However, the possibility of last male sperm predominance is related to male guarding behaviour.

The structure of arabidopsis NPR1 : its function as a salicylic acid receptor and a metal-binding protein

The Arabidopsis NPRI protein regulates systemic acquired resistance dependent on salicylic acid. Analyses by plant two-hybrid analysis in vivo and pull-down assays in vitro showed that the BTB/POZ domain of NPRI at the N-terminus serves as an autoinhibitory domain to negate the function of the transactivation domain at the C-terminus through direct binding of these two domains. I t was also shown that the binding of the BTB/POZ domain to the C-terminus of NPRI was abolished by SA treatment, suggesting that SA could interfere directly with this binding. By gel filtration, it was demonstrated that SA affects the conformation of full-length NPRl , confirming the role of NPRI as an SA receptor. Gel filtration analysis also indicated that NPRI could be converted from an oligomer to a dimer with SA treatment. Furthermore, one N-terminal deletion ~513 has been shown to act as a metal-binding protein and its two Cys-521 and Cys-529 are important for binding to Ni 2 + by pull-down assays.

The Gentleman's Magazine and Historical Chronicle - 1814 July to December Index and Supplements

The Gentleman's Magazine and Historical Chronicle was a monthly periodical published in England during the years of 1736-1833. The volumes of interest from 1812-1815 were written and compiled by Sylvanus Urban, Gentleman. These volumes were Printed in London by Nichols, Son and Bentley at Cicero's Head, Red Lion Passage and Fleet Street. Click on the pdf links to the right to view the monthly issue. This bound volume has been divided by months. The page divisions are as listed. Index pages 705-732 July pages 1-96 August pages 97-200 September pages 201-304 October pages 305-408 November pages 409-512 December pages 513-632 Supplement pages 633-704

The Gentleman's Magazine and Historical Chronicle - 1814 July

The Gentleman's Magazine and Historical Chronicle was a monthly periodical published in England during the years of 1736-1833. The volumes of interest from 1812-1815 were written and compiled by Sylvanus Urban, Gentleman. These volumes were Printed in London by Nichols, Son and Bentley at Cicero's Head, Red Lion Passage and Fleet Street. Click on the pdf links to the right to view the monthly issue. This bound volume has been divided by months. The page divisions are as listed. Index pages 705-732 July pages 1-96 August pages 97-200 September pages 201-304 October pages 305-408 November pages 409-512 December pages 513-632 Supplement pages 633-704

The Gentleman's Magazine and Historical Chronicle - 1814 August

The Gentleman's Magazine and Historical Chronicle was a monthly periodical published in England during the years of 1736-1833. The volumes of interest from 1812-1815 were written and compiled by Sylvanus Urban, Gentleman. These volumes were Printed in London by Nichols, Son and Bentley at Cicero's Head, Red Lion Passage and Fleet Street. Click on the pdf links to the right to view the monthly issue. This bound volume has been divided by months. The page divisions are as listed. Index pages 705-732 July pages 1-96 August pages 97-200 September pages 201-304 October pages 305-408 November pages 409-512 December pages 513-632 Supplement pages 633-704

The Gentleman's Magazine and Historical Chronicle - 1814 September

The Gentleman's Magazine and Historical Chronicle was a monthly periodical published in England during the years of 1736-1833. The volumes of interest from 1812-1815 were written and compiled by Sylvanus Urban, Gentleman. These volumes were Printed in London by Nichols, Son and Bentley at Cicero's Head, Red Lion Passage and Fleet Street. Click on the pdf links to the right to view the monthly issue. This bound volume has been divided by months. The page divisions are as listed. Index pages 705-732 July pages 1-96 August pages 97-200 September pages 201-304 October pages 305-408 November pages 409-512 December pages 513-632 Supplement pages 633-704

The Gentleman's Magazine and Historical Chronicle - 1814 October

The Gentleman's Magazine and Historical Chronicle was a monthly periodical published in England during the years of 1736-1833. The volumes of interest from 1812-1815 were written and compiled by Sylvanus Urban, Gentleman. These volumes were Printed in London by Nichols, Son and Bentley at Cicero's Head, Red Lion Passage and Fleet Street. Click on the pdf links to the right to view the monthly issue. This bound volume has been divided by months. The page divisions are as listed. Index pages 705-732 July pages 1-96 August pages 97-200 September pages 201-304 October pages 305-408 November pages 409-512 December pages 513-632 Supplement pages 633-704

The Gentleman's Magazine and Historical Chronicle - 1814 November

The Gentleman's Magazine and Historical Chronicle was a monthly periodical published in England during the years of 1736-1833. The volumes of interest from 1812-1815 were written and compiled by Sylvanus Urban, Gentleman. These volumes were Printed in London by Nichols, Son and Bentley at Cicero's Head, Red Lion Passage and Fleet Street. Click on the pdf links to the right to view the monthly issue. This bound volume has been divided by months. The page divisions are as listed. Index pages 705-732 July pages 1-96 August pages 97-200 September pages 201-304 October pages 305-408 November pages 409-512 December pages 513-632 Supplement pages 633-704

The Gentleman's Magazine and Historical Chronicle - 1814 December

The Gentleman's Magazine and Historical Chronicle was a monthly periodical published in England during the years of 1736-1833. The volumes of interest from 1812-1815 were written and compiled by Sylvanus Urban, Gentleman. These volumes were Printed in London by Nichols, Son and Bentley at Cicero's Head, Red Lion Passage and Fleet Street. Click on the pdf links to the right to view the monthly issue. This bound volume has been divided by months. The page divisions are as listed. Index pages 705-732 July pages 1-96 August pages 97-200 September pages 201-304 October pages 305-408 November pages 409-512 December pages 513-632 Supplement pages 633-704

Thorold Tunnel opening ceremony photographs, September 18,1968.

Construction on the Thorold tunnel began in 1965 and was completed in 1967. It was designed by H. G. Acres & Company Ltd. and built by Pitts-Atlas, a joint venture of C.A. Pitts, General Contractor Ltd., and Atlas Construction Company Ltd. The tunnel replaced two lift bridges (Bridge 9 at Ontario Paper Co. and Bridge 7) that carried traffic over the Welland Canal. The majority of the construction occurred during the winter months, when the canal was closed to shipping. The water was drained and concrete sections shaped liked tubes were poured, creating the tunnel. During the summer months, the end sections of the tunnel were constructed so that shipping could continue uninterrupted. The 24 million dollar project was financed jointly by the Department of Highways and the St. Lawrence Seaway Authority. The tunnel was officially opened on September 18, 1968.