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Subsurface information on source rock potential of the Eocene shale unit of the Abakaliki Fold Belt is limited and has not been widely discussed. The total organic carbon (TOC) content and results of rock-eval pyrolysis for nine shale samples, as well as the one-dimensional (1D) geochemical model, from an exploration well in the Abakaliki Fold Belt were used to evaluate the source rock potentials and timing of hydrocarbon generation of Lower Eocene source rocks. The TOC content values of all the samples exceeded the minimum threshold value of 0.5 wt.% required for potential source rocks. A pseudo-Van Krevelen plot for the shale samples indicated Type II–III organic matter capable of generating gaseous hydrocarbon at thermally mature subsurface levels. The 1D burial model suggests that the Eocene source rock is capable of generating oil and gas at the present time. The modelled transformation ratio trend indicates that a fair amount of hydrocarbon has been expelled from the source rocks. The results of this study indicate that the Eocene source units may have charged the overlying thin Eocene sand bodies of the Abakaliki Fold Belt.

The relationship of water chemistry and habitat stressors with selected biological metrics and indices was determined in a watershed using two different river segmentation scales. Results show that the scale used for data aggregation affects the correlation between stressors and the biology. This study showed that habitat appears to be a more important factor than chemistry when large stream segments are used to aggregate data.

The relative influences of water quality and in-streamhabitat on receiving water biology were investigatedin the Little Miami River, Ohio, a national and statescenic river located in the southwest corner of thestate. Monitored sample data for water chemistry,habitat, invertebrates and fish were obtained fromfederal and state sources and integrated via ageographical information system (GIS), using a uniquestream segmenting system. Locations and flowinformation for municipal wastewater treatment plants(WWTPs) were also integrated into the system. Therelative importance of water chemistry and habitat onbiological sample information was determined usingmultivariate forward stepwise regression. Theprincipal environmental factors that influencedbiological responses were in-stream habitat andpercent cumulative WWTP effluent at mean flow. Cumulative WWTP effluent at low flow dilution,nutrients and total toxic units from metals andammonia did not correlate with biological responses(e.g. number of mayfly species, invertebrate communityindex (ICI), number of fish species and index ofbiotic integrity (IBI)). We found the GIS-based datamethods to be highly useful for understanding theprincipal processes that guide receiving water health.

This study was performed to assess the role of exogenously administered polyamines on rat basilar and femoral artery contractile activity in vitro . With the endothelium removed, rings of tissue were set up in organ chambers to measure isometric tension. The polyamines (0.1–3mM), putrescine, spermidine, and spermine, were added to the tissue baths; after 30 min of incubation a cumulative concentration response curve (CRC) was obtained with either KCl or serotonin (5-HT). Additional CRCs were run with Ca ++ in high K + Krebs (60mM). In both tissues, the CRCs to KCl were shifted to the right in a dose-dependent manner for spermidine and spermine (1 & 3 mM) but not putrescine. Spermine (3mM) depressed the KCl maxima by 18.6% and 10.1% in the basilar and femoral artery respectively. For 5-HT CRCs, only spermine (3mM) slightly inhibited the maximal response in both tissues. The most potent action of spermine was on inhibition of Ca ++ responses in high K + where the EC 50 s were shifted 3.5 and 10 fold over control values in the basilar and femoral respectively. We conclude spermidine and spermine, but not putrescine, attenuate vascular smooth muscle contractions on the basilar and femoral arteries in vitro . The exact nature of the inhibition remains to be fully explored, but blockade of calcium entry through voltage operated Ca channels may play a role. Thus, certain polyamines may affect cerebral perfusion by inhibition of vascular contractility.

Background Because alpha 2 adrenoceptor agonists are used as adjuncts to anesthetics, their effects on the cerebrovascular circulation are of prime importance. We studied changes in the diameter of rat middle cerebral arteries after stimulation of alpha 2 adrenoceptors with UK14,304. Methods Rat middle cerebral arteries were isolated, cannulated at each end with a glass micropipette, and pressurized to 85 mmHg. The middle cerebral arteries were immersed in a bath (37 degrees C) containing physiologic saline solution, and luminally perfused with physiologic saline solution (100 microliters/ min). Changes in vessel diameter were measured after magnification with a microscope. Results Resting diameter of the middle cerebral arteries was 239 +/- 13 microns (n = 8) for the first study. A dose-dependent dilation was produced by addition of UK14,304 to the extraluminal bath; a 10-15% increase in diameter occurred at a concentration of 10(-4)M. The dilations produced by UK14,304 were blocked with selective alpha 2-antagonists, idazoxan and rauwolscine, but not by the selective alpha 1-antagonist, prazosin. The dilations could be blocked by removal of the endothelium, or the nitric oxide synthase inhibitor, N-nitro-L-arginine methyl ester (10(-5) M). The inhibitory effects of N-nitro-L-arginine methyl ester were reversed with the addition of 10(-3) M L-arginine, but not 10(-3) M D-arginine. Furthermore the dilation produced by UK14,304 was completely abolished with pertussis toxin (100 ng/ml). Conclusions It was concluded that the stimulation of alpha 2 adrenoceptors with UK14,304 produced a dilation in the rat middle cerebral artery that (1) was dependent on intact endothelium, (2) involved nitric oxide, and (3) acted via a pertussis toxin-sensitive G protein.

The 2000 Nuclear Data Sheets for A=142 by J.K. Tuli, with literature cutoff date of February 4, 2000, has been revised. The evaluated experimental data are presented for 16 known nuclides of mass 142 (Ba, Ce, Cs, Dy, Eu, Gd, Ho, I, La, Nd, Pm, Pr, Sm, Tb, Te, Xe). Comparing to the previous evaluation (2000Tu01) significant changes were done to the level schemes of Gd, Cs, Ce and Nd. For all nuclides, the more recent Q values have been added.

The Baskin School of Engineering at the University of California Santa Cruz has the Silicon Valley in its service area, and has working engineers from industry enrolled in its graduate engineering programs. In FIE 1996, we reported on plans to use a digital data link between a "matched pair" of classrooms (separated by a distance of about 30 miles and a range of coastal mountains) to link these students with our Santa Cruz campus graduate program, and thereby synchronously deliver an M.S. program in Network Engineering to Silicon Valley. In this paper we describe how our implementation matched our design, and evaluate the success of this undertaking from student and faculty perspectives. We also examine this program: it successes, the challenges faced, and the student and faculty experience and feedback. We discuss potential planned expansion of the program, and the some of the necessary or planned changes or modifications to the facilities used, including expansion to multiple sites, and extending from synchronous distance learning to uses of asynchronous delivery of some courses.

The development of new services for ATM networks continues, yet one service still required is end-to-end connection level priority/pre-emption (CLPP). This paper details the CLPP requirement, presents factors affecting its implementation, and provides a solution for the implementation of this service in the control plane of the ATM protocol reference model. Also presented is an analysis of a subset of the results obtained from over three thousand CLPP OPNET simulations, which were continually refined over a three-year period.

Future military defence networks will use asynchronous transfer mode technology. This paper defines the requirement for a connection level priority/pre-emption service in ATM to meet the needs of defence networks and presents the factors affecting the implementation of a priority/pre-emption service. A solution for the addition of this service to the control plane of the ATM protocol reference model is presented, followed by a discussion on its planned simulation with an OPNET model.

Future military defence networks will use asynchronous transfer mode (ATM) technology. This paper defines the requirement for a connection level priority/pre-emption service in ATM to meet the needs of defence networks and presents the factors affecting its implementation. A solution for the addition of the service to the control plane of the ATM protocol reference model is presented, followed by a discussion on its simulation in an OPNET model.

We have examined the potential to provide long-term or even permanent wound coverage in a mouse model of a 30% total body surface area burn using skin allografts. Treatment of the recipient mouse with rabbit anti-mouse thymocyte serum (ATS) followed by donor bone marrow infusion induces a state of specific unresponsiveness to the skin allograft without the need for chronic immunosuppression. Specifically, a B6AF1 mouse receives a burn on Day -2 relative to grafting, ATS on Day -1, and Day +2, a skin allograft from a C3H/He mouse on Day 0, and infusion of C3H/He donor bone marrow on Day +6. We studied three groups of burned mice: Group I, allograft control (n = 5); Group II, allograft plus ATS (n = 12); and Group III, allograft plus ATS and bone marrow infusion (n = 15). Mean graft survival was compared using a one-way analysis of variance and a Student-Newman-Keuls post hoc test. There was no statistical difference in animal mortality among any of the three groups, and there was no evidence of infectious morbidity. Mean skin allograft survival was as follows: Group I, 9 days; Group II, 29 days; and Group III, 66 days (P less than 0.05 vs Group I and II). Nine animals in Group III had intact hair bearing grafts at 90 days when the study was terminated. This study suggests the potential use of induced specific unresponsiveness to skin allografts for wound coverage in thermal injury without use of chronic immunosuppression. In our animal study this was accomplished without increased mortality or apparent infectious morbidity.