Mobility of the hydrated electron

The transient change in conductivity in diluted barium hydroxide solutions during and immediately after irradiation with single pulses of electrons from a 15-million-electron-volt linear accelerator was measured. Ionic mobility of the radiation-produced hydrated electrons was 1.84 x 10(-3)cm(-2) volt(-1) sec(-1) +/- 10 percent. This value corresponds to a diffusion constant of 4.75 x 10(-5) cm(2) sec(-1).     

Mummified pleistocene ostracods in alaska

Preserved soft parts of ostracod specimens were recovered from beach and lagoon sediments from the Gubik Formation, of Quaternary age, at Barrow, Alaska.     

Synchroneity of tropical and high-latitude Atlantic temperatures over the last glacial termination

A high-resolution western tropical Atlantic sea surface temperature (SST) record from the Cariaco Basin on the northern Venezuelan shelf, based on Mg/Ca values in surface-dwelling planktonic foraminifera, reveals that changes in SST over the last glacial termination are synchronous, within +/-30 to +/-90 years, with the Greenland Ice Sheet Project 2 air temperature proxy record and atmospheric methane record. The most prominent deglacial event in the Cariaco record occurred during the Younger Dryas time interval, when SSTs dropped by 3 degrees to 4 degrees C. A rapid southward shift in the atmospheric intertropical convergence zone could account for the synchroneity of tropical temperature, atmospheric methane, and high-latitude changes during the Younger Dryas.     

Environmental DNA sequencing primers for eutardigrades and bdelloid rotifers

Background  

The time it takes to isolate individuals from environmental samples and then extract DNA from each individual is one of the problems with generating molecular data from meiofauna such as eutardigrades and bdelloid rotifers. The lack of consistent morphological information and the extreme abundance of these classes makes morphological identification of rare, or even common cryptic taxa a large and unwieldy task. This limits the ability to perform large-scale surveys of the diversity of these organisms.     

Sulfated Polysaccharides from Macroalgae Are Potent Dual Inhibitors of Human ATP-Hydrolyzing Ectonucleotidases NPP1 and CD39

Extracellular ATP mediates proinflammatory and antiproliferative effects via activation of P2 nucleotide receptors. In contrast, its metabolite, the nucleoside adenosine, is strongly immunosuppressive and enhances tumor proliferation and metastasis. The conversion of ATP to adenosine is catalyzed by ectonucleotidases, which are expressed on immune cells and typically upregulated on tumor cells. In the present study, we identified sulfopolysaccharides from brown and red sea algae to act as potent dual inhibitors of the main ATP-hydrolyzing ectoenzymes, ectonucleotide pyrophosphatase/phosphodiesterase-1 (NPP1) and ecto-nucleoside triphosphate diphosphohydrolase-1 (NTPDase1, CD39), showing nano- to picomolar potency and displaying a non-competitive mechanism of inhibition. We showed that one of the sulfopolysaccharides tested as a representative example reduced adenosine formation at the surface of the human glioblastoma cell line U87 in a concentration-dependent manner. These natural products represent the most potent inhibitors of extracellular ATP hydrolysis known to date and have potential as novel therapeutics for the immunotherapy of cancer.     

Choline administration: modification of the central actions of atropine

The anticholinergic agent atropine decreases acetylcholine concentrations and increases high-affinity choline uptake in cortical and hippocampal regions of rat brain. Administration of choline 1 hour before atropine prevents both of these atropine-induced alterations. These findings suggest that alterations in acetylcholine precursor availability may modify the effects of centrally active anticholinergic agents.     

Sulphur supply affects morphology,growth and nutritional status of Tanzania Guinea grass and Mineirão stylo

Forage plants constitute the primary food source for ruminants, and their aboveground growth and belowground growth depend on mineral nutrient supply. The objective of this study was to identify and quantify variation in morphology, production and nutritional status in Panicum maximum cv. Tanzânia and Stylosanthes guianensis cv. Mineirão grown with varying levels of S availability. In an experimental setting, plants of both species received rates of S calculated to reflect suboptimum, adequate and excessive levels of the element. S had a direct effect on morphology and production in both species. S limitation altered the allocation of photosynthates between the aboveground and belowground portions of Guinea grass and stylo, and was associated with lower root dry mass production. Guinea grass plants increased root surface area as an adaptive mechanism when S was limiting in the growth medium. The relative chlorophyll index of recently expanded leaves was correlated with aboveground dry mass production. After the initial growth, Guinea grass and stylo plants showed similar S requirements and use efficiency to achieve the maximum of aboveground productivity, although leguminous plants have a substantially higher capacity for store S in the shoot tissue as compared to gramineous plants growing under similar availability of S in the medium. While applying S was necessary for increasing dry mass production in both species, planting these species together is a promising strategy for guaranteeing high yields of forage with a nutritional value that satisfies the S requirements of ruminants.     

Behavioural responses of harbour seals to human‐induced disturbances

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Improvement of nutritional quality of live feed for aquaculture: An overview

In hatcheries, the adequate supply of live feed has a vital role in feeding fish larvae, fry and fingerlings. Furthermore, the enhancement of the nutritional quality of live feeds is well‐developed techniques in aquaculture. Essential fatty acids (EFA) such as docosahexaenoic acid (DHA; C22:6 n?3), eicosapentaenoic acid (EPA; 20:5(n?3) and arachidonic acid (ARA; 20:4(n?6) and amino acids are an essential source of proteins for larval rearing of fish. However, the common practised live feeds used for the primary feeding such as rotifers and Artemia are naturally deficient in essential nutrient components. Hence, the improvement of the nutritional quality of live feeds with different oil emulsions and commercial diets, and manipulation of the feed are necessary for fish production. The production protocols of copepods, Moina and fairy shrimps as live feed are still underdeveloped in hatcheries. The different lipid sources using for the enrichment of Artemia and rotifers are not effective on other live feeds, especially copepods and cladocerans (Moina, Daphnia) and fairy shrimps. This review focuses on the importance of live feeds by the techniques of feed enhancement or enrichment of zooplankton by direct incorporation of nutrients for feeding of early stages of fish.