Host resistance to lung infection mediated by major vault protein in epithelial cells

The airway epithelium plays an essential role in innate immunity to lung pathogens. Ribonucleoprotein particles primarily composed of major vault protein (MVP) are highly expressed in cells that encounter xenobiotics. However, a clear biologic function for MVP is not established. We report here that MVP is rapidly recruited to lipid rafts when human lung epithelial cells are infected with Pseudomonas aeruginosa, and maximal recruitment is dependent on bacterial binding to the cystic fibrosis transmembrane conductance regulator. MVP was also essential for optimal epithelial cell internalization and clearance of P. aeruginosa. These results suggest that MVP makes a substantial contribution to epithelial cell-mediated resistance to infection.     

Effect of Golden Shiners on Plankton and Water Quality in Ponds Managed for Intensive Production

Water quality variables and plankton were monitored and compared between ponds that were stocked or not stocked with golden shiners in order to determine what changes occur in the plankton community and water quality of ponds managed for intensive production. Ponds with shiners had significantly lower phosphate and carbon dioxide concentrations and lower carbonate alkalinity than ponds without shiners. No significant difference in nitrite, nitrate, ammonia, temperature, secchi disk readings, or turbidity levels was found between the treatments. The standing crop of phytoplankton was nearly twice as great in ponds with fish. Ponds with fish had significantly fewer copepods but more rotifers than fishless ponds. Although the fish were offered a commercial feed with 29.5% protein and 1.5% crude fat at 3% of their biomass daily, they apparently continued to feed on crustacean zooplankton.     

Stable isotope ratios as naturally occurring tracers in the aquaculture food web

The natural isotopic ratio of ¹³C/¹²C (reported as δ C) in plant matter varies predictably among plant types. The isotopic ratio of an animal body reflects the isotopic ratio of the feed metabolized. By selecting inputs to an aquaculture feeding and/or fertilization system such that the components have significantly different δ C values, the relative meta-bolization of each of these inputs by the fish can be measured.

In tank-grown Tilapia aurea (δ C = −17), supplied feed (δ C = −18) provided the carbon incorporated into the fish body even though between feedings the fish consumed large quantities of algae (δ C = −22). In penaeid (δ C = −12) grow-out ponds, δ C analyses indicated that selected components of the feed pellet (average δC = −17; components: corn and sorghum δ C −12, soybeans δ C −25) were metabolized, while the benthic natural foods and other bottom organic matter (δ C = −21) provided little or no input. The value of such information for pond management and nutrition studies is clear.     

Threadfin shad impacts phytoplankton and zooplankton community structures in channel catfish ponds

Plankton community structure and chlorophyll a concentration were compared in twelve 0.1 ha earthen ponds co‐stocked with channel catfish (Ictalurus punctatus Rafinesque, 1818) in a multiple‐batch culture (initial biomass=5458 kg ha^?1) and a planktivore, threadfin shad (Dorosoma petenense Güther, 1867; initial biomass=449 kg ha^?1), during the April–November growing season. We used a completely randomized design in a 2 × 2 factorial arrangement to test the planktivore level (presence or absence of threadfin shad) and channel catfish feeding frequency (daily or every third day). Channel catfish were fed a 32% protein feed to apparent satiation on days fed. The presence of threadfin shad affected phytoplankton and zooplankton community structure more than did feeding frequency, and the impact in ponds was more pronounced after 1 July. The numbers of all major groups of zooplankton were lower in ponds with threadfin shad, but were unaffected by the feeding frequency. Chlorophyll a concentration before 1 July was higher in ponds with threadfin shad and unaffected by the feeding frequency, whereas after 1 July it was higher in ponds without threadfin shad and that were fed daily. Phytoplankton community structure after 1 July was dominated by nuisance algal bloom genera of cyanobacteria in ponds without threadfin shad and by Bacillariophyceae in ponds with threadfin shad.     

Climate data challenges in the 21st century

Climate data are dramatically increasing in volume and complexity, just as the users of these data in the scientific community and the public are rapidly increasing in number. A new paradigm of more open, user-friendly data access is needed to ensure that society can reduce vulnerability to climate variability and change, while at the same time exploiting opportunities that will occur.     

Autotrophic and heterotrophic production of micro-organisms in intensely-manured fish ponds,and related fish yields

Intensely-manured ponds produce 15–30 kg fish ha^?1 day^?1 with cow or chicken manure and nitrogen- and phosphate-rich fertilizers as the only nutritional inputs. The manure as it is supplied to the ponds is not a good fish food and does not produce good fish growth. Quantitative analysis shows that the production of all organisms, autotrophic and heterotrophic, pelagic and benthic, large enough to be used directly by the fish (i.e., larger than 37 microns) is adequate to account for less than half of the measured fish growth. Production within the microbial community that flourishes on and rapidly digests the manure organic matter is adequate to produce the measured fish growth. The fish appear to harvest the microorganisms at the level of bacteria and protozoa, by ingesting the small straw-like particles which comprise much of the manure and serve as the substrate for the microbial growth.