Shifts in biogenic carbon flow from particulate to dissolved forms under high carbon dioxide and warm ocean conditions

Photosynthesis by phytoplankton in sunlit surface waters transforms inorganic carbon and nutrients into organic matter, a portion of which is subsequently transported vertically through the water column by the process known as the biological carbon pump (BCP). The BCP sustains the steep vertical gradient in total dissolved carbon, thereby contributing to net carbon sequestration. Any changes in the vertical transportation of the organic matter as a result of future climate variations will directly affect surface ocean carbon dioxide (CO 2) concentrations, and subsequently influence oceanic uptake of atmospheric CO 2 and climate. Here we present results of experiments designed to investigate the potential effects of ocean acidification and warming on the BCP. These perturbation experiments were carried out in enclosures (3,000 L volume) in a controlled mesocosm facility that mimicked future pCO 2 (∼900 ppmv) and temperature (3°C higher than ambient) conditions. The elevated CO 2 and temperature treatments disproportionately enhanced the ratio of dissolved organic carbon (DOC) production to particulate organic carbon (POC) production, whereas the total organic carbon (TOC) production remained relatively constant under all conditions tested. A greater partitioning of organic carbon into the DOC pool indicated a shift in the organic carbon flow from the particulate to dissolved forms, which may affect the major pathways involved in organic carbon export and sequestration under future ocean conditions

Lactic acid bacteria affect serum cholesterol levels, harmful fecal enzyme activity, and fecal water content

<p>Abstract</p> <p>Background</p> <p>Lactic acid bacteria (LAB) are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as lower cholesterol. Although present in many foods, most trials have been in spreads or dairy products. Here we tested whether <it>Bifidobacteria </it>isolates could lower cholesterol, inhibit harmful enzyme activities, and control fecal water content.</p> <p>Methods</p> <p><it>In vitro </it>culture experiments were performed to evaluate the ability of <it>Bifidobacterium </it>spp. isolated from healthy Koreans (20~30 years old) to reduce cholesterol-levels in MRS broth containing polyoxyethanylcholesterol sebacate. Animal experiments were performed to investigate the effects on lowering cholesterol, inhibiting harmful enzyme activities, and controlling fecal water content. For animal studies, 0.2 ml of the selected strain cultures (10⁸~10⁹CFU/ml) were orally administered to SD rats (fed a high-cholesterol diet) every day for 2 weeks.</p> <p>Results</p> <p><it>B. longum </it>SPM1207 reduced serum total cholesterol and LDL levels significantly (<it>p </it>< 0.05), and slightly increased serum HDL. <it>B. longum </it>SPM1207 also increased fecal LAB levels and fecal water content, and reduced body weight and harmful intestinal enzyme activities.</p> <p>Conclusion</p> <p>Daily consumption of <it>B. longum </it>SPM1207 can help in managing mild to moderate hypercholesterolemia, with potential to improve human health by helping to prevent colon cancer and constipation.</p

Selective Leaching of Zinc from Spent Zinc-Carbon Battery with Ammoniacal Ammonium Carbonate

This paper describes the ammoniacal ammonium carbonate leaching behavior of zinc and manganese from spent zinc-carbon batteries. For selective extraction of Zn from the spent zinc-carbon battery, leaching tests were carried out as a function of process parameters such as concentration of (NH 4 ) 2 CO 3 , ammonia, temperature, time and pulp density. Physical methods of separation such as crushing was applied to reduce the material to 10-20 mm size followed by magnetic separation to separate iron with a recovery about 10 mass% leaving most of Zn and Mn in the non-magnetic fraction. Non-magnetic fraction was further subjected to sieving to separate 2.46 mm over and under size fractions. The oversize material was processed by eddy current separation to recover zinc sheet and carbon rods and plastics. The under size material with chemical composition of Zn 15.5 mass%, Mn 17.5 mass%, and Fe 1.4 mass% was used for leaching studies. Under the optimum leaching conditions (2.0 kmol/m 3 (NH 4 ) 2 CO 3 and 4.0 kmol/m 3 ammonia, 40 C, 100 g/L pulp density, 30 min and 250 rpm), the leaching efficiency of zinc and manganese was 80.2% and less than 0.1%, respectively, indicating the selective recovery of zinc from the spent zinc-carbon battery. An overall zinc recovery is about 88%

Ecologic correlation Study on Nutrients/Foods Intake and Mortal ity for Female Breast Cancer in Korea

In order to investigate the possible role of dieta-ry factors on the recent increase in mortality for female breast cancer in Korea, an ecologic correlation study between per capita intakes of nutrients and foods and the mortality for female breast cancer during the last 10 years was conducted. In spite of the possibility of an ecologic fallacy, the age-adjusted mortality rates for female breast cancer were positively correlated with protein from animal source, total lipid, total animal foods, animal foods to total intake, fresh fish and shellfish, milk and milk products, and meat and meat products. The rates were inversely associated with energy from cereal, total carbohydrate, vegetable foods to total intake, total vegetable foods, daily intake of cereals and grain products, and starch and starch roots. These results suggest that an increased intake of protein- and fat-rich foods rather than carbohydrate-rich foods or vegetables might be associated with the increase in mortality for breast cancer during the last 10 years in Korea

Improvement of Biological Effects of Root-Filling Materials for Primary Teeth by Incorporating Sodium Iodide

Therapeutic iodoform (CHI3) is commonly used as a root-filling material for primary teeth; however, the side effects of iodoform-containing materials, including early root resorption, have been reported. To overcome this problem, a water-soluble iodide (NaI)-incorporated root-filling material was developed. Calcium hydroxide, silicone oil, and NaI were incorporated in different weight proportions (30:30:X), and the resulting material was denoted DX (D5~D30), indicating the NaI content. As a control, iodoform instead of NaI was incorporated at a ratio of 30:30:30, and the material was denoted I30. The physicochemical (flow, film thickness, radiopacity, viscosity, water absorption, solubility, and ion releases) and biological (cytotoxicity, TRAP, ARS, and analysis of osteoclastic markers) properties were determined. The amount of iodine, sodium, and calcium ion releases and the pH were higher in D30 than I30, and the highest level of unknown extracted molecules was detected in I30. In the cell viability test, all groups except 100% D30 showed no cytotoxicity. In the 50% nontoxic extract, D30 showed decreased osteoclast formation compared with I30. In summary, NaI-incorporated materials showed adequate physicochemical properties and low osteoclast formation compared to their iodoform-counterpart. Thus, NaI-incorporated materials may be used as a substitute for iodoform-counterparts in root-filling materials after further (pre)clinical investigation