bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antidiabetic properties of polysaccharide- and polyphenolic-enriched fractions from the brown seaweedAscophyllum nodosumThis article is one of a selection of papers published in this special issue (part 2 of 2) on the Safety and Efficacy of Natural Health Products.
Authors: Zhang Junzeng , Tiller Christa , Shen Jingkai , Wang Can , Girouard Gabrielle S. , Dennis Dorothy , Barrow Colin J. , Miao Mingsan , Ewart H. Stephen 
Published: December 2007

We screened seaweed species from Atlantic Canada for antidiabetic activity by testing extracts for α-glucosidase inhibitory effect and glucose uptake stimulatory activity. An aqueous ethanolic extract of Ascophyllum nodosum was found to be active in both assays, inhibiting rat intestinal α-glucosidase (IC50= 77 μg/mL) and stimulating basal glucose uptake into 3T3-L1 adipocytes during a 20-minute incubation by about 3-fold (at 400 μg/mL extract). Bioassay-guided fractionation of the A. nodosum extract showed that α-glucosidase inhibition was associated with polyphenolic components in the extract. These polyphenolics, along with other constituents appeared to be responsible for the stimulatory activity on glucose uptake. However, attempts to further concentrate this activity through fractionation techniques were unsuccessful. A crude polyphenol extract (PPE), an enriched polyphenolic fraction (PPE-F1) and a polysaccharide extract (PSE) were prepared from commercial A. nodosum powder and administered to streptozotocin-diabetic mice for up to 4-weeks by daily gavage at 200 mg/kg body mass. PPE and PPE-F1 improved fasting serum glucose level in diabetic mice; however, the effect was only statistically significant at day 14. In addition, PPE-F1 was shown to blunt the rise in blood glucose after an oral sucrose tolerance test in diabetic mice. Mice treated with PPE and PPE-F1 had decreased blood total cholesterol and glycated serum protein levels compared with untreated diabetic mice, whereas PPE also normalized the reduction in liver glycogen level that occurred in diabetic animals. All 3 A. nodosum preparations improved blood antioxidant capacity.
Senecio latifolius induces in vitro hepatocytotoxicity in a human cell lineThis article is one of a selection of papers published in this special issue (part 2 of 2) on the Safety and Efficacy of Natural Health Products.
Authors: Neuman Manuela G. , Jia Angela Y. , Steenkamp Vanessa 
Published: December 2007

The objectives of this study were twofold: (i) to determine the mechanism(s) of Senecio -induced toxicity in human hepatoblastoma cells (HepG2) in vitro and whether such toxicity could be prevented using N-acetyl-cysteine (NAC), and (ii) to evaluate whether caspases are involved in Senecio-induced apoptosis. Cells were treated with aqueous extracts of Senecio (10 mg·mL–1) with and without NAC. Cytotoxicity was determined by using the MTT assay. Total glutathione (GSH) was measured by using the Tietze assay. Cells were also treated with aqueous extracts of Senecio in the presence or absence of 50 μmol/L caspase-3 inhibitor (IDN) for 24 h. Apoptosis was determined by transmission electron microscopy, and DNA fragmentation was determined by ELISA and terminal dUTP nick-end labelling (TUNEL). Senecio produced cytotoxicity and depleted GSH in a concentration- and time-dependent manner. A significant depletion in GSH was observed after 15 min (p < 0.001 vs. control), whereas significant cytotoxicity was only observed after 3 h (p < 0.001 vs. control). Treatment with NAC prevented Senecio-induced GSH depletion and resulted in a significant decrease in Senecio-induced cytotoxicity (p < 0.001 vs. NAC-untreated cells). Treatment with Senecio for 24 h resulted in 22% ± 2.5% (p < 0.001) apoptosis (vs. control). Pretreatment with 50 μmol caspase inhibitor reduced Senecio-induced apoptosis significantly (vs. non-exposed to IDN) (12% ± 1.5%; p < 0.05). Our results suggest the mechanism of Senecio-induced cytotoxicity in HepG2 cells in vitro involves depletion of cellular GSH. Cytotoxicity is reduced by supplementation with NAC, which thus prevents GSH depletion. Caspase activation is involved in Senecio-induced apoptosis.
Adjuvant activities of saponins from the root of Polygala senega L.This article is one of a selection of papers published in this special issue (part 2 of 2) on the Safety and Efficacy of Natural Health Products.
Authors: Katselis Georgios S. , Estrada Alberto , Gorecki Dennis K.J. , Barl Branka 
Published: December 2007

Eight pure triterpenoid saponin compounds isolated from the root of Polygala senega L., a plant indigenous to the Canadian prairies, were evaluated for their immunological activity in mouse models. The specific antibody responses of the IgG2asubclass increased significantly when isolated P. senega saponins were used as adjuvants in the immunization of mice with OVA antigen. In addition, increased IL-2 levels were observed in spleen cell cultures from P. senega saponin-immunized mice after in vitro secondary antigen stimulation. The saponins were tested for their toxicity in mice by using a haemolytic activity assay and found to be less toxic than Quillaja saponaria saponins that have long been used as adjuvants in vaccine formulations. This study has shown the potential of P. senega saponins to be considered as a natural source of vaccine adjuvants with biological activity equivalent to the current commercially available saponin adjuvants.
Soil, human society and the environment
Authors: Blum W. E. H. , Warkentin B. P. , Frossard E. 
Published: December 2007

Abstract

Soils, forming the top layer of the Earth's crust, are a mixture of mineral particles, organic matter, water, air and living organisms. Processes between these components perform vital functions within ecosystems. The soil forms an interface between the geosphere, the biosphere, the hydrosphere and the atmosphere, and is a largely non-renewable resource.
Ugolini & Warkentin
show the fruitful relationships which geology and soil science have established since the birth of soil science, and how these two disciplines together could contribute to solve future problems.

The dynamic soil system delivers functions and services vital for human societies and the environment. Soil is the basis for food and biomass production, and plays a central role as a habitat for biota and as a gene pool. Moreover, it stores, filters, buffers and transforms a large variety of substances, including water, inorganic and organic compounds, and is a major sink and source for greenhouse gases. Soil provides raw materials for human use. It also serves as the basis for human activities (landscape and heritage) and for our technical and socio-economic infrastructure, delivering materials for their implementation and maintenance.
Soils as sources and sinks of greenhouse gases
Authors: Leifeld Jens 
Published: December 2007

Abstract

Soils annually emit between 6.8 and 7.9 Gt CO
2
equivalents, mainly as CH
4
from intact peatlands and from rice agriculture; as N
2
O from unmanaged and managed soils; and as CO
2
from land-use change. Methane emissions attributable to other wetlands add another 1.6–3.8 Gt CO
2
equivalents. From a global standpoint, N
2
O from unmanaged soils and CH
4
from peatlands and other wetlands make soils naturally net greenhouse gas emitters. In addition, the storage of carbon in soils and the fluxes of CH
4
and N
2
O have been changed by anthropogenic effects towards emission rates 52 to 72% above those under natural conditions before the dawn of intensive agriculture and land-use change. Land-use changes on mineral soils induced most of the recorded losses of soil organic matter (SOM), but there is evidence that proper agricultural management of soil resources is able to recover some of these losses and to maintain soil functions. However, the discrepancy between so-called ‘sequestration potentials’ and the measures already adopted is amazingly large. Globally, only about 5% of the cropped areas is managed according to practices such as no tillage or organic farming. The contribution of soil loss by erosion, desertification and sealing to global oxidative SOM losses is uncertain; however, in the case of soil erosion, it is considered to be a major factor in global SOM decline. Mitigation options calculated for SOM restoration, reduced CH
4
and N
2
O emissions are able to alleviate mean annual emissions by 1.2 to 2.9 Gt CO
2
equivalents, mainly as a result of carbon sequestration, which is the most efficient measure for the next few decades. In the longer term, however, the large potential for reducing CH
4
and N
2
O emissions outweigh the finite capacity of soils to recover C. Integrated assessment of net greenhouse-gas fluxes is key for evaluating management practices aimed at reducing overall emissions. From the viewpoint of climate change and taking into consideration the mean fluxes of CO
2
, CH
4
and N
2
O, peatland protection is more favourable than peatland cultivation in the long term. The most important gaps in our understanding appear to be with regard to estimating fluxes along with soil erosion and desertification processes, in the extent of peatland cultivation; the role of black carbon formation, natural ‘background’ sequestration rates of undisturbed soils; and the net response of soils, particularly in cold regions, to global warming. With regard to the societal perception of soil contributing to the global cycling of greenhouse gases, it is important to emphasize that significant proportions of the emissions are inevitably linked to intensive agriculture.
Understanding of a soil system derived from a single bed-rock, for improved vineyard management in Southern France
Authors: Dosso M. , Philippon O. , Ruellan A. 
Published: December 2007

Abstract

The ‘Massif de La Clape’ in Southern France is a calcareous hill with a semi-arid Mediterranean climate. All the agricultural lands are under vineyards managed by different châteaux. The objective of this work was to understand the soil system of Château X to solve a problem of vineyard mortality and to show how the exceptional variability of the soil conditions could be taken into account for optimal vineyard management. The soils of Château X are derived from sandstone that fills a basin of about 40 ha, surrounded by a calcareous formation. The study of the soil system showed the presence of four soil domains, two located at the top of the basin and mainly derived from eluviation, and two located at the bottom of the basin, which are mainly derived from illuviation. The domain located at the very bottom of the basin showed an accumulation of swelling clays in its Bt
M
horizon. The zones of highest vine mortality were located at the bottom of the basin, on the soil with the Bt
M
horizon. This mortality was explained by the strong discontinuity between the E and the Bt
M
horizons, with the accumulation of Cu at toxic concentrations as a consequence of lateral water flows. In this soil, root growth was hindered by the high bulk density of the Bt
M
horizon. In order to solve the problem of vine mortality and manage the vineyard according to the different soil conditions observed in the topo-sequence, several proposals are made.
Cultural soilscapes
Authors: Wells E. C. 
Published: December 2007

Abstract
While soil is normally studied as the outcome of natural geological and chemical processes, soil research by archaeologists, geographers and other social scientists focuses on the human behavioural dimensions of soil formation. As a result, ‘cultural soilscape’ is an analytical concept common to both Earth and social sciences that encourages a more holistic, transdisciplinary approach to studying soil formation processes. This paper introduces the concept of cultural soilscape and reviews important archaeological work on this theme over the past decade.
From agricultural geology to hydropedology: forging links within the twenty-first-century geoscience community
Authors: Landa Edward R. 
Published: December 2007

Abstract

Despite historical linkages, the fields of geology and soil science have developed along largely divergent paths in the United States during much of the mid- to late-twentieth century. The shift in recent decades within both disciplines, towards greater emphasis on environmental-quality issues and a systems approach, has created new opportunities for collaboration and cross-training. Because of the importance of the soil as a dynamic interface between the hydrosphere, biosphere, atmosphere and lithosphere, introductory and advanced soil-science classes are now taught in a number of Earth and environmental science departments. The National Research Council's recent report,
Basic Research Opportunities in Earth Science
, highlights the soil zone as part of the land surface to groundwater ‘critical zone’ requiring additional investigation. To better prepare geology undergraduates to deal with complex environmental problems, their training should include a fundamental understanding of the nature and properties of soils. Those undergraduate geology students with an interest in this area should be encouraged to view soil science as a viable Earth-science specialty area for graduate study.
Policies for a sustainable use of soil resources
Authors: Montanarella Luca 
Published: December 2007

Abstract
Soil protection policies have been developed at National level in a number of countries. The US Soil Conservation Act, the German Federal Soil Protection Act, and the Soil Action Plan for England are just some examples of such policies. International policies for a sustainable use of soil resources have been developed both at regional level and at global level. The Alpine Convention and the upcoming EU Thematic Strategy for Soil Protection are two examples of regional policies addressing soil protection. No specific binding global policy exists for soil protection. Nevertheless, a number of environmental protection policies address soil-protection aspects, like the climate-change convention, the biodiversity convention and the desertification convention. Further development of the EU Thematic Strategy for Soil Protection will make it possible to explore new methods of international cooperation in this field.
Nutrient balances for improving the use-efficiency of non-renewable resources: experiences from Switzerland and Southeast Asia
Authors: Menzi H. , Gerber P. 
Published: December 2007

Abstract
Simple nutrient balances can be a valuable tool to assess and visualize whether farming systems are in equilibrium or not with respect to nutrient inputs and outputs. Thus, they can raise awareness about environmental risks of agricultural production, and especially intensive livestock production. They are also a valuable tool for policy development and implementation processes. In this paper, we discuss how a nutrient-balance approach can help to improve the awareness of different stakeholders about the ecological impacts of agriculture and the efficient use of nutrients. While the example from Switzerland demonstrates the potential ecological benefits of compulsory nutrient balancing, the examples from Asia demonstrate how a combination of nutrient balancing and geographic information system (GIS) was used to identify hot-spots with respect to insufficient and excessive P input, and we will discuss a nutrient-balance method developed to improve nutrient management in the rapidly growing intensive livestock-production sector.
Parameterization of meander-belt elements in high-resolution three-dimensional seismic data using the GeoTime cube and modern analogues
Authors: Rabelo I. R. , Luthi S. M. , Van Vliet L. J. 
Published: December 2007

Abstract
The parametric quantification of geological bodies from high-resolution seismic data helps in understanding and predicting their occurrences, but is often hampered by layer distortions caused by post-depositional processes. A method called GeoTime cube is presented that overcomes this by creating a seismic volume between two near-isochronous geological markers in which the vertical axis corresponds approximately to relative geologic time. This volume is no longer affected by post-depositional deformations, a feature that greatly facilitates the extraction of sedimentary elements of interest. A case study of a fluvio-estuarine reservoir from Suriname demonstrates how fluvial point bars, channel fills and crevasse splays can be extracted from the GeoTime cube. Their geometries are quantified with the help of recent analogues. Meandering rivers are found to show relatively constant curvatures and a characteristic spacing of their meander loops. Cubic splines are suitable parametric descriptors of such river paths. Point bars are their main depositional product and can be approximated by two intersecting circle segments, representing the initial and the final position of the meander loop. The axis joining the circle centres corresponds to the direction of accretion, and the normals to these axes describe the drainage trend. Knowledge of these parameters from a limited area can be used to stochastically model the meander belt in the up- and downstream direction.
Seismic geomorphology of Palaeozoic collapse features in the Fort Worth Basin (USA)
Authors: Sullivan E. C. , Marfurt K. J. , Blumentritt C. , Ammerman M. 
Published: December 2007

Abstract
Modern multi-trace geometric attributes produce three-dimensional volumes that can facilitate the recognition of karst geomorphology by avoiding the need to pre-interpret irregular horizons and by enhancing subseismic lateral variations in reflectivity. These geometric attributes include the well-established coherence technology, coupled with recent developments in spectrally limited estimates of volumetric curvature. Coherence measures lateral changes in waveform, and as such, is often sensitive to joints, small faults, sinkholes and collapse features. The many components of reflector curvature, including the most negative, most positive, Gaussian curvature and related shape indices (e.g. valleys, saddles, domes), are complimentary to coherence measures. Short wavelength estimates of curvature will illuminate small-scale lineaments while longer wavelength estimates of curvature illuminate more subtle flexures and compaction features. We show the results of applying a variety of multi-trace geometric attributes to a three-dimensional seismic volume from the Fort Worth Basin, where a collapse system extends vertically some 800m from the Ordovician Ellenburger carbonates through the dominantly siliciclastic Mississippian— Pennsylvanian interval. The collapse features in our data set appear as rounded, sinkhole-like appearances on time and horizon slices in the Pennsylvanian Marble Falls Limestones and the Ellenburger horizon displays features that can be interpreted as cockpit karst, dolines and frying pan valleys. Although a variety of palaeocave breccia facies in core and image logs indicate that the Ellenburger surface has been karsted, these breccias are not confined to the mega collapse features visible in seismic. The large (up to 700 m diameter) collapse chimneys can be shown in multi-spectral curvature attributes to have elongate rhombohedral shapes associated with intersections of Pennsylvanian age, field-scale to basin-scale, basement lineaments and faults. Isochores indicate greatest tectonic growth on faults from Mississippian until early Pennsylvanian, coincident with thickest fill of collapse features. Thus we interpret the origin of the chimneys to be primarily tectonic. The multi-trace geometric attributes permit better imaging of the three-dimensional shapes of the collapse features, provide better constraints on timing of their formation, allow us to begin to separate karst processes from tectonic processes and provide a means of predicting most likely locations of fluid movement along faults.
Fluvial seismic geomorphology: a view from the surface
Authors: Ethridge F. G. , Schumm S. A. 
Published: December 2007

Abstract
Three-dimensional seismic data enable geoscientists to image the stratigraphic record along selected stratal or time slices. These slices provide detailed images of the planform geometry of ancient depositional systems and environments. In this presentation we attempt to provide a partial answer to the question: what kind of information do nonmarine channel and valley patterns and parameters convey regarding sediment load, channel stability, structural or climatic history of the area, and palaeochannel and reservoir architecture? Geomorphologists have long recognized four basic channel patterns: straight, meandering, braided and anastomosing. They have also developed a classification based on aerial pattern and sediment load. This relationship seems straightforward; however the patterns form a continuum with a great deal of complexity related to degree and character of sinuosity, braiding and anabranching. For example an equal- width sinuous pattern suggests moderate to high lateral stability, and low bed load to suspended load deposits. A wide bend sinuous pattern suggests low to moderate lateral stability, and higher bed load to suspended load deposits. Because of convergence and divergence, interpretation of controls on palaeochannel patterns is difficult. Nevertheless, a better understanding of the various controls on modem river morphology and dynamics can produce useful information regarding palaeo-systems. For example, river type (straight, braided, meandering and anastomosing) depends upon upstream controls such as geologic history (glaciated v. non-glaciated systems), tectonics (relief), lithology (sediment type) and climate (hydrology and vegetation), and downstream controls such as base-level (up and down) and length (avulsion). In addition, factors such as bedrock, active tectonics, floods and vegetation cause considerable pattern variability. Only by taking into account the effect of these controls and by using all available data can there be more predictive and interpretive explanations of seismic data.
Seismic expression of turbidity-current and bottom-current processes on the Northern Mauritanian continental slope
Authors: Schwab A. M. , Tremblay S. , Hurst A. 
Published: December 2007

Abstract
The architectural framework of the Mauritanian continental slope is characterized by a complex mixture of gravity and bottom current deposits that modify the pelagic background sedimentation. Since the Neogene, the Mauritanian passive margin bottom-currents have been the main control on the construction and topography of the slope. On the lower slope, numerous sediment waves and contourites occur. Turbidity-current channel incisions and slope failures are responsible for the destructive remodelling of the slope. The upper-slope incisions have a dendritic pattern, and converge into highly sinuous main channels in the lower slope, where the channels become constructional with levees and lateral accretion packages. Subsurface data exhibit older slope failures, which guide the location of later turbidity-current channel pathways. The seabed and shallow seismic expression of deep-water slope deposits generated by variable gravity-transport and bottom-current processes in offshore Northern Mauritania can be compared with analogous settings in lower resolution, deeper subsurface seismic data to gain a better understanding of the slope environment and deposits.
Doing Theology: Engaging the Public
Authors: Elliot Alison 
Published: December 2007

AbstractThis article examines the characteristics of some of the contexts in which public theology is done. Examples are taken from Scotland and particularly the experience of representatives of the Church of Scotland. Three publics are identified as target audiences: an institutional public in which official positions are debated and defended; a constructed public in which theological understanding is developed in the company of others; and a personal public which characterizes some forms of broadcasting. Discourse in each public has different characteristics, drawing on distinctive theological assumptions about church and faith. The article examines how public theology can draw strength from practice in each context.