Effects of Aramchol on in vitro bile cholesterol crystallization and bile acid detergency

The hydrophilic bile acid ursodeoxycholic acid may dissolve cholesterol gallstones and is beneficial in cholestatic liver diseases. The C20 fatty acid‐bile acid conjugate arachidyl amido cholanoic acid (Aramchol) could be a more effective option. We therefore studied its effects on cholesterol crystallization and on bile salt‐induced cytotoxicity. Effects of Aramchol at therapeutically relevant concentrations on crystallization in supersaturated model biles (by microscopy and chemical measurement), on the ternary cholesterol‐taurocholate‐phosphatidylcholine phase diagram, and on micelle ? vesicle transitions (by serial dilution or by incubation of cholesterol‐phosphatidylcholine vesicles with taurocholate) were evaluated. Effects on bile salt‐induced cytotoxicity were determined in erythrocytes and CaCo2 cells. Incorporation of Aramchol in model biles did not change micellar cholesterol solubilization, induced a small rightward shift of crystal‐containing zones of the ternary phase diagram, exerted no appreciable effects on vesicle ? micelle transitions and had only minor effects on cholesterol crystallization. Bile salt‐induced cytotoxicity was increased by Aramchol in all models. Since Aramchol does not affect cholesterol crystallization, its previously reported beneficial effects in animal gallstone models should relate to other mechanisms. Since Aramchol increases bile salt detergency, it is not likely to be beneficial in cholestatic liver disease.     

Phenolic content and antioxidant capacity of supercritical carbon dioxide-treated and air-classified oat bran concentrate microwave-irradiated in water or ethanol at varying temperatures

Oat bran concentrate (OBC) was defatted with supercritical carbon dioxide (SCD), then microwave-irradiated (MI) at 50, 100 or 150 °C for 10 min in water, 50% or 100% ethanol, and extract pH, soluble solids, phenolic content (PC) and antioxidant capacity (AC) were analysed. OBC was air-classified into five fractions and MI in water at 150 °C. OBC without SCD and microwave irradiation was extracted at 22 °C. Most effective temperature during microwave irradiation for maximising extraction of PC and AC was 150 °C. Defatted OBC in 50% ethanol and MI at 150 °C extracted greatest PC and AC. SCD treatment slightly reduced PC and AC. OBC extracted in water or 50% ethanol at 22 °C without microwave irradiation had similar PC and AC than OBC MI at 150 °C, but much higher levels were observed for latter heat treatment using absolute ethanol. Air-classification shows potential to enhance PC and AC.     

Balancing nutrient inputs to Lake Kivu

The primary production in meromictic Lake Kivu is sustained by external nutrient inputs and by internal loading due to upwelling caused by sub-aquatic sources. We present here the results of external loading of phosphorus (P), nitrogen (N) and silica (Si) by rivers and atmospheric deposition measured from 2006 to 2008. These external inputs are compared to internal loading. The input of soluble-reactive P (SRP), supplied in equal parts from rivers and atmospheric deposition, adds up to 230 t P yr^− 1, 20 times less than total P load. Ammonium (mainly via rainwater) and nitrate (mainly via rivers) are primary sources of the dissolved N load (5400 t N yr^− 1), with both species contributing ∼ 50%. Dissolved Si input (40,000 t Si yr^− 1) is unique in that only ∼ 60% enters by rivers, while the remaining ∼ 40% comes from sub-aquatic sources and atmospheric deposition is negligible. Based on the molar nutrient ratios, we identify P as the limiting factor for algae production. Despite the strong anthropogenic impact on the catchment and the high particle erosion (74 t km^− 2 yr^− 1), the area-specific nutrient mobilization is rather low. The external nutrient input is therefore not the cause for the reported increase of methane production in the last decades. External loading to the epilimnion plays a lesser role for all three nutrients (∼ 10% for SRP, ∼ 25% for dissolved N and ∼ 45% for dissolved Si), as compared to the lake-internal loading by upwelling (90%, 75% and 55%, respectively). Lake Kivu, therefore, is similar to other East African large lakes in that the internal loading exceeds the external loading. Despite the substantial uncertainty of the load estimates of up to 50%, we can conclude that the observed nutrient input is consistent with the primary production of 260 g C m^− 2 yr^− 1 recently measured by Sarmento et al. (2006) and also consistent with the lake-internal fluxes established by Pasche et al. (in press).     

Model-Supported Impact Assessment for the Water Sector in Central Germany Under Climate Change—A Case Study

Climate change challenges water managers and researchers to find sustainable management solutions, in order to avoid undesirable impacts on water resources, environment and water-dependent sectors. Needed are projections into the future for the main driving forces, the resulting pressures on water resources, and quantification of the impacts. Modeling studies can play an important role in investigating, quantifying, and communicating possible impacts of climate change, with account of uncertainty of the results. However, climate change related impacts and a need for adaptation still play a minor role in current river basin management plans that have to comply e.g. with the EU Water Framework Directive (WFD). One important reason is that climate impact assessment is generally done in research institutes, while management plans are designed by practitioners working in national and regional environmental agencies and water supply companies. Knowledge transfer from science to practice and visa versa is often missing. In the present study, we propose a methodology and a case study for model-supported decision making in the water sector applicable to a participatory water resources planning process. The methodology is applied in a case study investigating climate change impacts on water resources. The case study area is the German State of Saxony-Anhalt, where the task was to develop a climate change impact assessment including possible adaptation measures as basis for a federal adaptation directive.     

Syngas formation in methane flames and carbon monoxide release during quenching

Following a recent investigation into chemi-ionization and chemiluminescence during gradual aeration of small, laminar methane flames, we proposed that partial oxidation products, or syngas constituents, formed in the pre-flame zone well below the luminous region, were responsible for the observed effects. We therefore map temperature, CO, and H₂ for geometries and conditions relevant to burners in domestic boiler systems, to assess the potential hazard of CO release into the ambient atmosphere, should any partial quenching occur. CO concentrations peaks of 5.5 volume % are recorded in the core surrounding the axis. Appreciable CO concentrations are also found in the absence of added air. Experiments on various burner port geometries and temperatures suggest that this is not due to air entrainment at the flame base but to diffusion from zones closer to the flame. Next, quenching surfaces such as grids, perforated plates and flame trap matrices of different metals are progressively lowered into the flame. To avoid flow line distortion, suction aspirates the quenched products. The highest emission rate occurs with the quenching plane some 4 mm above the burner; further lowering of the quenching surface causes flame extinction. The maximum CO release is close to converting 10% of the CH₄ feed, with some variation with quenching material. Expressing this potential release in terms of, e.g. boiler power, predicts a potentially serious hazard. Results of numerical simulations adequately parallel the experimental sampling profiles and provide insights into local concentrations, as well as the spatially resolved CO flux, which is calculated for a parabolic inlet flow profile. Integration across the stream implies, on the basis of the simulation, a possible tripling of the experimental CO release, were quenching simply to release the local gas composition into the atmosphere. Comparison with experiment suggests some chemical interaction with the quenching surface.     

Efficiency and equity considerations in financing agricultural research and extension

Benefits resulting from agricultural research and extension activities conducted in one region may affect producers and consumers throughout the country. Measurement of these benefit spillovers is required to equitably and efficiently finance these activities. Spillover benefit ratios per dollar of internal benefits for all farm production regions in the United States are calculated using an economic surplus framework to account for the effects of research and extension on both producers and consumers. In nine out of ten regions, the spillover ratios are greater than one, indicating that benefits accruing outside the region conducting research and extension activities are greater than the benefits accruing internally to the region. The average spillover ratio, which is 3.71 for all regions, is greater than the ratio of federal expenditures to regional expenditures. The implication of these ratios being unequal is that the federal contribution would need to be increased in order for regional costs to match regional benefits.     

Phenotypes of yeast mutants lacking the mitochondrial protein Pet20p

The pet20-delta deletion in Saccharomyces cerevisiae causes diminished growth on media containing non-fermentable carbon sources when incubated at both above and below the 30 degrees C optimal growth temperature. Furthermore, the pet20-delta strain has a greatly reduced level of cytochrome c, especially at 37 degrees C. The pet20-delta strain was sensitive to high NaCl and CaCl2 concentrations, hydrogen peroxide, oligomycin, polymixin B, amphotericin B and fluconazole. Biochemical fractionation and immunofluorescence staining demonstrated that Pet20p is located primarily in the mitochondria. Rhodamine B staining of pet20-delta cells showed an altered mitochondrial staining, indicating the possible lack of the mitochondrial membrane potential. We suggest that PET20 encodes a protein required for proper assembly or maintenance of mitochondrial components, but does not serve an enzymatic role. It is also possible that Pet20p may constitute a non-catalytic subunit of an uncharacterized mitochondrial complex or serve as a transporter or a coupling factor.     

Solution Enhancement and Post-enhancement Storage Effects on the Quality, Sensory, and Retail Display Characteristics of Beef Triceps Brachii Muscles

Beef triceps brachii muscles (6 d postmortem; n= 15; muscle sections n= 45) were sectioned into 3rds and allocated to 1 of 3 treatments. The treatments were untreated (CNT), or injected at a 12% pump rate with either tap water‐only (H₂O) or a solution comprising tetrasodium pyrophosphate and sodium chloride (TSPP/ NaCl) at 0.4% and 1.0% target final product weight concentrations, respectively. Each muscle (comprising all 3 treatments) was then allocated to 2, 14, or 28 d of vacuum‐packaged 1°C storage. Purge losses during storage were greatest (P < 0.05) for H₂O muscles and least (P < 0.05) for TSPP/NaCl muscles. Purge losses also increased (P < 0.05) from 2 d to 14 d of storage. Steaks enhanced with TSPP/NaCl had less (P < 0.05) free water and lower (P < 0.05) cooking losses than either CNT or H₂O steaks. Storage duration did not affect (P > 0.05) Warner‐Bratzler shear force (WBS) or sensory tenderness, but juiciness decreased (P < 0.05) with increased storage duration. While storage duration did not impact (P > 0.05) instrumental color characteristics, aerobic plate counts generally increased during storage. The TSPP/NaCl steaks had lower (P < 0.05) WBS values and improved (P < 0.05) sensory tenderness and juiciness characteristics compared with CNT or H₂O steaks. While CNT steaks had greater (P < 0.05) L* values (lightness) than TSPP/NaCl steaks, TSPP/NaCl steaks had similar (P > 0.05) oxymyoglobin proportions (630/580 nm) and a* values (redness) as CNT steaks. These results suggest enhancement with TSPP/NaCl can improve triceps brachii yield and palatability characteristics. Increased post‐enhancement storage did not impact or worsened palatability while increasing purge losses, suggesting general deleterious effects of increased postmortem storage for this muscle.     

Public Perceptions and Actions towards Sustainable Groundwater Management in the Pacific Northwest Region,USA

A 50-question survey was developed by the land grant universities in the Pacific Northwest to document public awareness, aptitudes, attitudes and actions toward water issues in the states of Alaska, Idaho, Oregon and Washington, USA. Demographic data were also collected about the survey respondents. The statistically designed survey was completed by over 50% of the 1800 residents who were solicited for the study. The public consider clean groundwater a high priority issue. Survey respondents currently consider groundwater quality to be good; however, most people are unaware of groundwater quantity issues. In the last 5 years, a majority of survey respondents have taken voluntary actions both to protect groundwater quality and to conserve the use of this resource. People want the government to focus more attention on groundwater issues; however, they are unwilling to pay increased taxes to achieve this end. Based on this survey, the land grant universities need to increase groundwater education programmes for the public using television, radio, newspapers and the Internet rather than by the traditional workshop delivery methods.     

Axial Compression of Footings in Cohesionless Soils. II: Bearing Capacity

An extensive database of full-scale field load tests was used to examine the bearing capacity for footings in cohesionless soils. Each load test curve was evaluated consistently to determine the interpreted failure load (i.e., bearing capacity) using the L1-L2 method. This test value then was compared with the theoretical bearing capacity, computed primarily using the basic Vesi? model. The comparisons show that, for footing widths B>1?m, the field results agree very well with the Vesi? predictions. However, for B<1?m, the results indicated a relationship between B and the predicted-to-measured bearing capacity ratio. Accordingly, a simple modification was made to the bearing capacity equation, and the resulting predictions are very good.