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Catchments provide water and sediment to downstream sedimentary systems, and these form individual source-to-sink systems. Source-to-sink systems comprise adjacent linked segments, commonly hinterland catchments, alluvial- and coastal plains, the continental shelf, continental slope and submarine fan. The dimensions of the catchment and how it scales to downstream segments provides insight into the sedimentary and tectonic controls that influence the morphology and sedimentation patterns in a basins evolution. In ancient sedimentary successions, where the sedimentary routing system is buried and inaccessible for study, or fragmented due to uplift and erosion, using scaling relationships can provide a powerful tool to understand the complete sedimentary system. Observational data from modern sedimentary systems provide an opportunity to create morphological and sedimentological scaling relationships of segments on the entire source-to-sink system. However, previous studies on global modern source-to-sink systems have typically been based on a limited number of examples restricted by the data available at the time and the methodology used to analyze large datasets. In the last decade, the volume and quality of remotely sensed information has significantly improved so that it is now timely to revisit scaling relationships of modern source-to-sink systems' segment morphologies, and discuss the implications of those r esults for sedimentological parameters and applicability to ancient source-to-sink systems. The results of this reanalysis show that dimensions of the catchment and submarine fan segments scale internally in terms of fan width, length and area. In addition, fan area scales to its largest hinterland catchment area in agreement with previous studies, however, it is important to consider all catchments that contribute sediment to a basin floor region. In paleogeographic settings, where individual submarine fans are difficult to tie to a single catchment, and where basin floor systems are amalgamated, the contributing sediment discharge of all catchments may be significant and likely influence the scale of its submarine fan. Accommodation versus sediment supply in relation to relative sea level change are important controls on the position of the shoreline which vary considerably from system to system over time and space, thus influencing morphological relationships between source-to-sink segments. The continental shelf should therefore be viewed as a transient geomorphic feature rather than a segment of a source-to-sink system. Furthermore, the continental slope length should not be used to scale other segments of the source-to-sink system, which contradicts previous research. The underlying tectonic and sedimentological control on the continental shelf and slope segments, in addition to the subjective interpretation of their basinward boundaries, may render those segments unsuitable for scaling the morphology of other segments. The study highlights both the temporal variability and complexity of controls that influence the morphology and scaling relationships of internal and adjacent linked source-to-sink segments, and the need to place this in a framework of both tectonic and sedimentological history.

Empirical rate data show that aggradation and progradation rates are negatively correlated with the duration they are averaged over. This means that we cannot understand deep time sedimentation rates in terms of the abundant rate data we have from modern environments. We are addressing this by investigating how growth of a sediment volume in multiple directions affects time-averaged accumulation rates that do not necessarily measure all directions of growth. We derive a mathematical model from mass-balance considerations of a sedimentary deposit that grows without erosion. We show that the non-linear relationship between the lengths, areas and volumes of growing objects require that time-averaged sedimentation rates are time-scale dependent when a deposit grows in multiple directions. We generate rate compilations from simple synthetic stratigraphies, which show that we can reproduce the empirical rate compilations by requiring only that deposition occur in a dynamic mosaic of sequential patches in which the areal extent of deposition increases with time-scale as described by our mathematical model. Our model has two implications with application in stratigraphic analysis. The first is that it provides a theoretical model of why we cannot expect high stratigraphic completeness if we measure a deposit in fewer directions than it has grown. The second is that it provides a framework by which to attribute anomalies in the stratigraphic completeness of a one-dimensional or two-dimensional sample to scaling effects or erosional hiatuses.

The South Lake Albert Basin (SLAB) is part of the Albertine graben , the northernmost part of the western arm of the East African Rift System (EARS). The study focused on interpretation of three-dimension (3D) seismic and suites of wireline log datasets, construction of 3D models, facies analysis , surface geological mapping and integrating both subsurface and surface data to assess reservoir rock properties. From previous studies, low to moderate reservoir quality (porosity, permeability and Vshale) was realized, and most of the drilled wells encountered two or more separate stacked oil accumulations (complex reservoirs) whose lateral extent had not been well understood and that was attributed to poor reservoir property distribution. The major aim of this study is to quantify the reservoir rock properties and integrating both subsurface and surface data in order to evaluate the reservoir property distribution within the study area, with specific objectives of (1) interpreting subsurface and facies modelling data and (2) to conduct field (surface) data sampling, analysis and interpretation (3) integrating both subsurface and surface data. From the obtained results, it was deduced that the lithology from facies modelling (subsurface results) and field geological mapping (surface results) data and the reservoir rock properties in both Kaiso Tonya and Kingfisher areas generally had moderate to good values for all the interpreted reservoir rock properties that were quantified however, the section under Lake Albert had better results. In addition, the reservoir rock properties for both subsurface and surface data were changing at very short intervals with intercalations of clay, silt, fine and coarse sands that was attributed to short changes in climatic (wet and dry) conditions that happened over time during the sedimentation process. It was further deduced that sediment compartmentalization and intercalation have effect on the reservoir rock properties.

The Middle to Late Triassic Snadd Formation represents one of the later stages of Early Mesozoic infilling of the Barents Sea Basin, expressed by a silicilastic wedge prograding from the southeast, where sediments were shed from the Uralide Orogeny. The formation was deposited in a shallow (100–500 m) basin facing the Boreal part of the Panthalassa Ocean, and the progradation reached its peak at the Svalbard Archipelago which has since been uplifted and where outcrops are exposed as the time-equivalent Botneheia and De Geerdalen formations. The Snadd Formation includes depositional environments ranging from offshore shale through shallow marine to fluvial, arranged in discrete stratigraphic sequences. Here we present a refined sequence stratigraphic framework for the Snadd Formation. Two second order sequences have been interpreted within the limits of the study area, divided into six third order sequences. The two second order sequences are split along an Intra Carnian maximum flooding surface. Depositional elements inherent to the sequence stratigraphic framework are also interpreted and extrapolated so as to describe the regional distribution of potential reservoir sandstones and the control exerted on the development of third order sequences. Different depositional environments from various datasets and scales of observation show the progressive development of a prograding delta across more than 700 km from a proximal position on the Finnmark Platform to a distal position on Edgeoya. Regional correlation of well logs and 2D seismic coupled with detailed depositional environment interpretation from 3D seismic and core has resulted in basin-wide palaeogeographic reconstruction of the formation throughout the Norwegian part of the Barents Sea, with implications for understanding the distribution and evolution of depositional systems during this large-scale basin infill.

The southeastern Piedmont of the USA was severely gullied during the early 20th century. A thick canopy established by reforestation in many areas now inhibits the identification or mapping of gullies by aerial photography or other conventional remote sensing methods. An Airborne Laser-Scanning (ALS or LiDAR) mapping mission flown for the U.S. Forest Service in April, 2004 acquired bare-Earth topographic data. This paper tests the ability of the ALS topographic data to identify headwater channels and gullies for two branching gully systems in forested areas and to extract gully morphologic information. Comparisons are made with field traverses using differential GPS and reference cross sections measured by leveling surveys. At the gully network scale, LiDAR data provide accurate maps – the best available – with robust detection of small gullies except where they are narrow or parallel and closely spaced. Errors in mapping channel location and network topological connectivity under forest canopy increase with attempts to identify smaller features such as large rills. The ability of LiDAR data to map gullies and channels in a forested landscape should improve channel-network maps and topological models. At the gully reach scale, attempts to use LiDAR data to extract gully cross-section morphologic information under forest canopy were less successful due to systematic underestimation of gully depths and overestimation of gully top widths. Limited morphologic accuracy of the data set at this scale may be due to low bare-Earth point densities, shadowing of gully bottoms, and filtering of topographic discontinuities during post-processing. The ALS data used in this study are not suitable for detailed morphometric analysis or subtle change detection to monitor gullies or develop sediment budgets. Data collection may be improved by orienting flights over gullies and with increased point densities through improved scanner technology or better filtering and software capabilities to differentiate between vegetation and ground surfaces.

Noninvasive assessment of left ventricular filling pressures by echocardiography has been validated by invasive hemodynamic studies and correlated with clinical findings. A comprehensive echocardiographic examination based on the referral diagnosis and patient symptomatology routinely includes efforts to measure specific parameters of left ventricular diastolic function. We provide a step-by-step approach to goal-directed echocardiographic assessment of diastolic function.

Three compositionally distinctive groups of oils identified in central Montana by biomarker analyses are also recognized by the unique compositions of their light hydrocarbon (gasoline range) fraction. The majority of oils produced from Paleozoic pools (Pennsylvanian Tyler–Amsden interval) group into one broad category based on the distribution of C 20 –C 40 biomarkers. These oils not only have the lowest Paraffin Indices and relative concentrations of normal heptane, but are readily distinguishable from the other compositional groups by using selected “Mango” parameters. However, the biomarker-based subdivision of this group into at least two sub-families is not reflected in the gasoline range fraction, suggesting little effect of source rock host lithology on the distribution of C 5 –C 8 hydrocarbons. Oils occurring predominantly in Jurassic–Cretaceous reservoirs display different biomarker and gasoline range characteristics, including Paraffin Indices, K1 parameter and relative concentrations of C 7 compounds, and are classified in two separate compositional categories. In contrast to oils from the Tyler–Amsden interval, the oils produced from the Mesozoic strata are amongst the most mature oils in the study area. The unique biomarker/light hydrocarbon signatures are likely due to different source organic matter. Secondary alteration of oil due to biodegradation and migration, although recognized, appears less significant. The results indicate the overall usefulness of gasoline range compositions in delineating compositional affinities of crude oils in central Montana, clearly suggesting that the oils found in Paleozoic and Mesozoic reservoirs belong to different petroleum systems.

As in all Aptian Salt Basins off western Africa, the post-rift evolution of the Lower Congo Basin offshore Angola was greatly influenced by raft tectonics. We suggest that rafting in the Lower Congo Basin took place during relatively short periods (7–10 Ma), characterized by high strain rates separated by longer periods (15–35 Ma), characterized by low strain rates. The high strain rate periods are dated as: Aptian–Late Cretaceous, Late Eocene–Late Oligocene and Late Miocene–Recent. With respect to the Tertiary development we have obtained a positive correlation between sedimentary thickness and cumulative stretching, suggesting sedimentary loading as an important driving mechanism for raft tectonics. During the Tertiary two different types of depocentres developed. These are (i) broad first order depocentres governed by regional subsidence and (ii) narrower elongated second order depocentres governed by growth on active faults. Within the study area the depocentres seem to have migrated from the west towards the east.

Characteristics of stream types were surveyed within the Chattooga River watershed in the Blue Ridge Mountains of southeastern US. The 728 km 2 watershed is contained within the states of Georgia, South Carolina and North Carolina. The stream types of about 190 streams of various sizes were determined as perennial, intermittent or ephemeral using a combination of physical and biological indicators. The key indicators were defined as channel erosion into the landscape and aquatic insects. Comparisons were made between the measured stream characteristics and their hydrologic orders. The stream data indicated that most headwater order 1 streams were either ephemeral or intermittent. Order 2 streams were divided among intermittent, perennial and ephemeral. All order 3 streams and larger ones were perennial, except for one small, third order intermittent stream with an 18% channel gradient. The data suggest that the total 4670 km stream network was approximately equally divided between defined channels (28% perennial and 17% intermittent) and undefined channels (55% ephemeral). Changes in stream order produced exponential changes in the total number, mean segment length and total length of streams. The fine detail included about 15,630 order 1 channels with a combined length of 2740 km. Comparisons are provided between the estimated extent of stream types and the ‘blue-line’ streams identified on the US Geological Survey topographic contour maps at both 1:24,000 and 1:100,000 scales. Streams indicated on the 1:100,000 scale maps identified about 650 km of streams, while the 1:24,000 scale mapped the blue-line stream extent at 970 km. Of the estimated 1300 km of perennial streams, the topographic maps identified 50–75%, depending on scale. However, only about 14–21% of the entire stream network which includes perennial, intermittent and ephemeral streams were marked on the topographic contour maps. Recommendations are included for improving the consistency of how ‘stream orders’ and ‘stream types’ are delineated. Since water quality protection measures are often related to the stream type, improvement in identifying streams should improve stream protection design and help to prevent impacts on water quality and aquatic habitat.

Various segments of the 3'-nontranslated region of the renal glutaminase (GA) mRNA were tested for their ability to enhance turnover and pH responsiveness. The combined effects were retained in the 340-base R-2 segment. However, the combined R-1 and R-3 fragments also imparted a partial destabilization and pH responsiveness to a chimeric beta-globin mRNA. RNA electrophoretic mobility shift assays indicated that cytosolic extracts of rat renal cortex contain a protein that binds to the R-2 and R-3 RNAs. The binding observed with the R-2 RNA was mapped to a direct repeat of an 8-base AU sequence. This binding was effectively competed with an excess of the same RNA, but not by adjacent or unrelated RNAs. UV cross-linking experiments identified a 48-kDa protein that binds to the AU repeats of the R-2 RNA. The apparent binding of this protein was greatly reduced in renal cytosolic extracts prepared from acutely acidotic rats. Two related RNA sequences in the R-3 segment also exhibited specific binding. However, the latter binding was more effectively competed by R-2 RNA than by itself, indicating that the homologous sites may be weaker binding sites for the same 48-kDa protein. Thus, a single protein may bind specifically to multiple instability elements within the 3'-nontranslated region of the GA mRNA and mediate its pH-responsive stabilization.

The primary goal of educational alcohol prevention programs is to lower the overall prevalence of alcohol use and abuse among populations at risk for negative alcohol-related outcomes. Youth are primarily targeted for prevention since there is ample evidence that alcohol-related injuries constitute a major risk for this group in particular. Prevention includes a goal to delay the onset of regular consumption and decrease high-risk consumption among youth who do drink. No matter what definition of alcohol use or abuse is adopted, the goal of prevention is to lower the proportion of youth who engage in that type of use. Among those who already use or abuse alcohol by any definition, the goal of prevention is to reduce the average intensity of use and prevent the progression of consumption to more severe levels. Reducing high-risk consumption may include preventing drinking while driving as well as promoting "responsible" drinking. Prevention programs may include a focus on reducing or eliminating consumption among occasional users. Prevention is also targeted at adults, primarily focusing on reduction of alcohol-impaired driving, reduction of alcohol-related violence, and reduction of alcohol consumption during pregnancy.

Sequence stratigraphic models are: (1) discussed from a theoretical point of view, with emphasis on a systematical discussion of the breakdown of depositional cycles produced by changes in relative sea-level and sediment supply into systems tracts and, (2) questioned by discussing and schematically showing alternative scenarios to the established ones. The “shoreline trajectory”, defined as the cross-sectional shoreline migration path along the depositional dip, is a useful building block for describing the internal architecture of the depositional cycles and their contained systems tracts. The shoreline trajectories can be grouped into discrete classes including accretionary and non-accretionary forced regression, normal regression, and accretionary and non-accretionary transgression. Depositional cycles formed as a response to successive rises and falls of relative sea-level should be divided into four, and not three systems tracts, which is the most common in the literature. Three key surfaces can encompass a complete cycle. These are the surfaces of maximum regression and transgression, and the subaerial unconformity formed during relative sea-level fall. The correlative conformity to the subaerial unconformity should correspond to the time of lowest relative sea-level. Variability of the lowstand wedge and highstand systems tracts can be treated together, since both are taking place during rising relative sea-level with sediment supply being larger than the accommodation being generated. The resultant progradation may or may not be interrupted by transgressive events. Three end-member scenarios for the transgressive systems tract can be envisaged: non-accretionary transgression; accretionary transgression; and backstepping by combined transgressions and normal regressions. Important controls on the variability of the forced regressive systems tract are the gradients of the shoreline trajectory and the fronting depositional foundation. Basin floor mass-gravity deposition may occur within all four systems tracts and will eventually take place both in a ramp and shelf-slope-basin setting if the receiving basin extends into deep waters and is oversupplied with sediments.

One-year follow-up data from three seventh-grade cohorts of Project SMART were examined to assess the effects of two social psychology-based programs within each of six subgroups: males, females, Asians, blacks, Hispanics, and whites. The three cohorts (total N = 5,070) were those receiving curriculum or serving as controls as seventh-graders in 1982-1983, 1983-1984, and 1984-1985 school years. The outcome measures used were composite indices based on lifetime and recent use items for cigarettes, alcohol, and marijuana. The major analysis was ANCOVA on classroom means for the composite indices at posttest, using pretest classroom means for the indices as a covariate. The results showed clear prevention effects for females but not for males. Overall prevention effects were strongest for cigarette smoking, but were also evident for alcohol. Significant sex by program interactions, showing differential program effects for males and females, were found for cigarettes and marijuana, but not for alcohol. There was a nonsignificant trend suggesting that the programs were most effective for Asians and least effective for whites. 0 1990 Academic

We report a case of a rare aneurysm of the right ventricular outflow tract, and a pseudoaneurysm of the right ventricle caused by a remote motor vehicle accident. (J Am Soc Echocardiogr 2002;15:1025-6.)

Program development processes for the Television, School, and Family Project, a school-based smoking prevention and cessation project, are presented in this article. We first review applications of social-psychological and communications theory to school-based and mass media program development. These include the three broad areas of (a) mediators of mass media effects on behavior change, (b) the social influences approach to smoking prevention, and (c) a self-management and social support approach to smoking cessation. A program development model for school-based mass media efficacy trials, with a summary of formative research and pilot study processes, is then presented. The importance of reciprocal support among school district administrators, project research staff, and television station personnel is emphasized with recommendations for future research and demonstration efforts.

Treatment joiners were differentiated from non-joiners when examined across six worksite clinic locations in the Los Angeles area. Predictors examined included preprogram smoking, demographic variables, smoking by significant others, behavioral expectations to quit, and self-efficacy regarding completing treatment and resisting urges to smoke. Non-joiners reported higher preprogram smoking levels and more friends and children who smoked.

Research is needed to identify risk factors specifically associated with the development of substance abuse. The current study explored the possibility that adolescents classified as having a problem behavior prone orientation (Type II) are predisposed to more rapid alcohol use onset compared to more normally socialized (Type I) adolescents. It was hypothesized that both types of adolescents would increase their alcohol use over time, but that problem behavior prone adolescents would increase their rates of alcohol consumption more rapidly than would normally socialized adolescents. Using ANCOVA (with baseline alcohol use as a covariate) and t tests (examining only nondrinkers at baseline), the hypotheses were strongly supported. Both Type I and Type II adolescents significantly increased their alcohol use over a one-year period. Type II adolescents, in comparison to Type I adolescents, had significantly higher alcohol use. The greater alcohol use among Type II adolescents was attributed to their problem behavior prone orientation. The findings suggest the existence of two different developmental pathways of alcohol use onset, one initiated by normally socialized adolescents and the other by adolescents with a problem behavior prone orientation. Future alcohol abuse prevention programs may benefit from tailored intervention strategies which take into account population specific risk factors.

This paper describes a valuable tool for tracing the origins of impurities introduced into high-purity germanium during the zone-refining and crystal growing processes. Small single crystals are located in the polycrystalline zone-refined ingots by chemical etching techniques and the concentration and type of residual impurities in these crystals are determined by Hall effect, conductivity measurements and photothermal ionization spectroscopy. Results are presented which indicate that the common impurities boron, aluminum and gallium all segregate more slowly in zone refining than is predicted by simple theory. This anomaly is attributed to compound formation involving the impurities and the zone-refining boat material.

The excitation spectra of shallow acceptors in ultra-pure germanium (109 cm-3 < NA − ND < 1012 cm-3 were studied using Fourier Transform Spectroscopy and photothermal excitation. Using samples with a total number of less than 108 acceptor atoms, the signal to noise ratio was better than 100. In the purest samples the natural width of some excited states was found to be below the instrumental resolution of 0.03 meV (= 0.25 cm-1). Some new observations involve the resolution of lines of states near the top of the valence band and the discovery of two unknown shallow acceptors.

Two drug abuse prevention curricula were tested to determine their efficacy in preventing the onset of tobacco, alcohol, and marijuana use among adolescents. The first program focused on prevention through social pressure resistance training. The second featured affective education approaches to prevention. Curricula were tested on seventh grade students. Subjects were pretested just prior to the program and were post-tested at 12 and 24 months. Post-test analyses indicated that the social program delivered to seventh grade subjects was effective in delaying the onset of tobacco, alcohol, and marijuana use. No preventive effect of the affective education program was observed. By the final post-test, classrooms that had received the affective program had significantly more drug use than controls.

A major issue in smoking prevention research is that no study has tried to equate program success expectancies across experimental and placebo control conditions. Equivalent overall program success expectancies should be established to help rule out the effects of extra-theoretical variables which influence program outcomes. The present study tested whether an attention-placebo (information based) smoking prevention program would produce equivalent expectancies about the likelihood of program success in comparison to an experimental social influences program. To try to equate program success expectancies, the design of the two programs differed in content but was similar in procedure. Fourteen middle schools were randomly assigned to the two conditions. As hypothesized, baseline expectancies were found to predict outcome measures, even after controlling for baseline smoking intentions, ethnic group, and gender. Second, the equivalence of program expectancies at posttest was tested. Youths held equivalent overall expectancies for success across conditions. This study suggested the need to control for program expectancies in prevention research, and showed that program expectancies could be controlled for by equating process of program delivery.

The purpose of this study was to examine psychosocial predictors of self-initiated smoking cessation among high school students. Students from nine high schools were pretested using a questionnaire which assessed smoking behavior, beliefs about positive and negative consequences of smoking, moral attitudes toward smoking, normative expectations about smoking, rebelliousness, peer smoking and parent smoking. Smokers identified at pretest were reexamined three months and fifteen months later. Three variables, moral attitudes, peer smoking and positive beliefs about smoking significantly discriminated continuing smokers from quitters at the three-month posttest. Three different variables, negative beliefs about smoking, parental smoking and rebelliousness significantly discriminated between those who quit and later relapsed and those who quit and maintained their non-smoking status at the 15 month posttest. Smoking characteristics at pretest failed to discriminate either those who would quit or those who would maintain their non-smoking status. Results support the development of public information programs which encourage early cessation of smoking which feature the development of appropriate attitudes and beliefs and which foster social support.

This note establishes the value of observation of etch-pit distributions as a guide in the selection of germanium for use in lithium-drifted germanium detectors. Results are presented showing a very good correlation between the etch-pit distribution and detector performance for a number of crystals pulled on the 111 axis. It is inferred that mechanical strain produced by thermal conditions in the crystal growing process is the major source of potential charge trapping sites in the final detector.

It is shown that high-purity germanium can be grown with rather simple precautions against airborne contamination. Several crystals have been grown with net impurity concentrations less than 5×10 10 /cm 3 over more than half the crystal length. Some initial results with detectors made from this materials are presented.

Results demonstrating the successful use of a gold surface-barrier as a thin-window p + termination of the intrinsic region of a lithium-drifted germanium detector are reviewed; these results are a rebutal to statements recently made by Dearnaley et al. in this journal.