New palaeoceanographic constraints on the Eocene-Oligocene Transition in the Pacific (abstract of paper presented at AGU Fall Meeting, San Francisco, 6-10 Dec 2002)

The Eocene-Oligocene (E/O) transition represents perhaps the most pivotal phase in the shift from Cenozoic greenhouse to icehouse and is marked by the most pronounced shift in the calcite compensation depth (CCD) over the last 100 Myr. Yet detailed palaeoceanographic records for these important events are rare because of the lack of well-dated, expanded deep-sea sedimentary sections containing well-preserved calcareous microfossils. Recently, during Ocean Drilling Program Leg 199, we recovered a series of high-quality E/O sections across a latitudinal and depth transect in the central tropical Pacific Ocean. These sections provide an excellent opportunity to improve our understanding of the palaeoceanographic chain of events that took place across this important interval in the region of the world where the CCD perturbation is believed to be most extreme and in the largest ocean basin. Here, we report new high-resolution records of bulk sediment d13C, d18O and percent carbonate from ODP Sites 1217 through 1220. Our results show the following: (i) Bulk records from the central tropical Pacific have the potential to provide a remarkably clean and detailed chemostratigraphy for the E/O transition. (ii) CCD deepening occurred remarkably rapidly (initial depression <50 ka) and, in the most expanded section, at the shallowest end of the transect (Site 1218), as a two-step shift. (iii) The form of this two-step shift is strikingly similar to the bulk d18O record on the build up to Oi-1. (iv) The intermediate plateau that occurs between the two steps in the d18O series fits very well with the main ~100-120 ky eccentricity cycles observed in multi-sensor track data and their amplitude modulation (plateau = one cycle). (v) The interval of maximum CCD as defined by high carbonate sediment content (≥60% CO3) at the deeper end of the transect (Site 1220) correlates with the onset of Oi-1 and lasts for ~250 ka. (vi) Hitherto unrecorded extreme perturbations to low d18O and d13C values occur in the uppermost Eocene at Site 1218. (vii) d18O and d13C records from this site show significantly more structure within Oi-1 than published records (characteristic features of obliquity control, with a small imprint of precession)

Journal Staff

BACKGROUND: It has been hypothesised that an upregulation of the neuropeptide substance P (SP) and its preferred receptor, the neurokinin-1 receptor (NK-1 R), is a causative factor in inducing tenocyte hypercellularity, a characteristic of tendinosis, through both proliferative and antiapoptotic stimuli. We have demonstrated earlier that SP stimulates proliferation of human tenocytes in culture. AIM: The aim of this study was to investigate whether SP can mediate an antiapoptotic effect in tumour necrosis factor-α (TNF-α)-induced apoptosis of human tenocytes in vitro. RESULTS: A majority (approximately 75%) of tenocytes in culture were immunopositive for TNF Receptor-1 and TNF Receptor-2. Exposure of the cells to TNF-α significantly decreased cell viability, as shown with crystal violet staining. TNF-α furthermore significantly increased the amount of caspase-10 and caspase-3 mRNA, as well as both BID and cleaved-poly ADP ribosome polymerase (c-PARP) protein. Incubation of SP together with TNF-α resulted in a decreased amount of BID and c-PARP, and in a reduced lactate dehydrogenase release, as compared to incubation with TNF-α alone. The SP effect was blocked with a NK-1 R inhibitor. DISCUSSION: This study shows that SP, through stimulation of the NK-1 R, has the ability to reduce TNF-α-induced apoptosis of human tenocytes. Considering that SP has previously been shown to stimulate tenocyte proliferation, the study confirms SP as a potent regulator of cell-turnover in tendon tissue, capable of stimulating hypercellularity through different mechanisms. This gives further support for the theory that the upregulated amount of SP seen in tendinosis could contribute to hypercellularity

Activity Loyalty and Recreation Participation: A Conceptual Perspective

Marketers have long had an interest in understanding consumers\u27 purchasing/usage patterns. This paper proposes a conceptual definition of activity loyalty. This variable may be central to understanding why individuals develop different rates and frequency of participation

Assessment of International Tourists\u27 Perception on Local Foods in Tanzania

Consumption of local food is broadly recognized as an essential part of tourists’ experience. Locally distinctive food can be important both as a tourism attraction in itself and in helping to shape the image of a destination. Local food experiences have the potential to contribute considerably to sustainable development, help maintain regional identities and support agricultural diversification. While local foods have the potential to reduce poverty in rural communities, their image and perception to tourists remain largely unexamined. The aim of this paper is to evaluate the way international tourists perceive local food in Tanzania. Data was collected using questionnaires (N = 540) at Kilimanjaro International Airport (KIA), which serves tourists who have just completed their visits from the most popular “Northern Circuit” of Tanzania National Parks. The findings show that (74.5%) of the respondents agreed that overall local food was of good quality and (58.5%) agreed that local food was safe to eat. However, respondents felt strongly that the hotels they stayed in did not provide many varieties of local foods (42.3%) or sufficient information about local foods (36.5%)

International Tourism: An Unrecognized Potential in Rural Tourism Development

This paper presents an overview of international tourism and its role in rural economic development. It briefly describes the current approaches to rural economic development followed by a brief look at international tourism 1n the United States, and the potential for tourism in rural areas is examined. An initial step in assessing the extent to which international tourists visit rural America is determining the factors which currently attract those visitors to rural areas. The purpose of this paper is to profile potential international travelers to rural areas

Issues in Rural Community Tourism Development

Policy makers are turning to tourism as a potential industry force that may bring both economic and demographic stability to American rural communities. The systematic planning and appropriate utilization of community related physical, economic, and socio-cultural attributes is the key to the establishment of sustainable tourism. This paper focuses on several issues that are increasingly recognized as critical factors in the community system. Both quality of life and sense of place are emphasized. The paper concludes with broadly defined guidelines for future planning toward sustainable development

The Former USSR Forest Sector and Capital Constraints

This study presents an analysis of the likely capital constraints that Russia and other republics of the former Soviet Union will face under evolving competitive market conditions. As such it serves as a first step in determining the future of forestry in the former Soviet republics, particularly Russia. The objectives of the study are to identify likely competitive price responses in the former Soviet Union market for roundwood, the likely impacts of different levels of roundwood exports on international prices and the feedback of international prices may have on the domestic price. The study postulates that, without adequate levels of investments in harvesting and processing capacity, domestic demand -- with below international market prices -- will further erode the existing capital base. As a consequence capital constraints will lead to serious shortages in wood supply in the near future in the absence of capital investment. A more rapid approach to market prices would force serious inflationary pressures on domestic demand. The results of the study may be used to determine possible policy strategies needed to forestall a decline in output in the forest sector. A collapse of the forest sector will lead to serious wood shortages in meeting the domestic demands of former Soviet republics and may lead to a deterioration in the environment. Lower returns to the sector will limit forest management activities. The forest sector may also miss the opportunity to raise foreign exchange in international markets

Tracking the Equator Into the Paleogene (abstract of paper presented at AGU Fall Meeting, San Francisco, 8-12 Dec 2003)

Stratigraphy has been compiled for 63 tropical Pacific drill sites that sample lower Neogene and Paleogene sediments. These Sites derive from drilling on DSDP Leg 5 through ODP Leg 199. All Sites have been put on the biostratigraphic and paleomagnetic timescale refined by Leg 199 scientists. Sediment accumulation rates have been calculated for ten intervals ranging in age from 10 Ma to 56 Ma. A simple fixed hotspot model was used for Pacific lithospheric plate rotation in reconstructing the position of the selected sites for each of these ten intervals. The reconstruction of all intervals show the development of a tongue of relatively high accumulation rates associated with the oceanographic divergence at the geographic equator. The estimated position of the geographic equator based on these reconstructions lies consistently south of the position of the equator based on the rotation model used. However, the southward displacement is generally 2 degrees of latitude or less. We believe that this relatively small disagreement between the two estimates of equatorial position back to 56 Ma indicates: 1) Whatever hotspot movement that may have occurred in the interval between 40 and 56 Ma did not affect the motion of the Pacific plate; its motion after 40 Ma appears to have been approximately the same as before 40 Ma. 2) The estimated rate of true polar wander during the interval of 40 - 56 Ma must be very small (~0.125$\deg$/m.y.) and is probably not significant (i.e., well within the error of these reconstructions)

Three newly-discovered M-dwarf companions of Solar Neighbourhood stars

We present low-resolution spectroscopy of newly-discovered candidate companions to three stars in the Solar Neighbourhood. All three companions are M dwarfs, with spectral types ranging from M4 to M9.5. In two cases, G85-55`B' (M6) and G87-9`B' (M4), we have circumstantial evidence from spectroscopy, photometry and limited astrometry that the systems are physical binaries; in the third, G216-7B (M9.5), comparison of POSS II IIIaF plate material and the 2MASS image indicates common proper motion. The primary star in this system, G216-7A (M0), appears itself to be an unresolved, nearly equal-mass binary. All three low-mass companions are highly likely to be stellar in nature, although G216-7B lies very close to the hydrogen-burning limit.Comment: Accepted for publication in PASP; 21 pages, 6 figure