Creatine Supplementation Prevents the Accumulation of Fat in the Livers of Rats Fed a High-Fat Diet

The aim of the present study was to examine the effects of creatine supplementation on liver fat accumulation induced by a high-fat diet in rats. Rats were fed 1 of 3 different diets for 3 wk: a control liquid diet (C), a high-fat liquid diet (HF), or a high-fat liquid diet supplemented with creatine (HFC). The C and HF diets contained, respectively, 35 and 71% of energy derived from fat. Creatine supplementation involved the addition of 1% (wt:v) of creatine monohydrate to the liquid diet. The HF diet increased total liver fat concentration, liver TG, and liver TBARS and decreased the hepatic S-adenosylmethionine (SAM) concentration. Creatine supplementation normalized all of these perturbations. Creatine supplementation significantly decreased the renal activity of L-arginine:glycine amidinotransferase and plasma guanidinoacetate and prevented the decrease in hepatic SAM concentration in rats fed the HF diet. However, there was no change in either the phosphatidylcholine:phosphatidylethanolamine (PE) ratio or PE N-methyltransferase activity. The HF diet decreased mRNA for PPAR as well as 2 of its targets, carnitine palmitoyltransferase and long-chain acylCoA dehydrogenase. Creatine supplementation normalized these mRNA levels. In conclusion, creatine supplementation prevented the fatty liver induced by feeding rats a HF diet, probably by normalization of the expression of key genes of beta-oxidation. J. Nutr. 141: 1799-1804, 2011.

Nitrification in a Vertisol subsoil and its relationship to the accumulation of ammonium-nitrogen at depth

Unusually high concentrations of ammonium have been observed in a Vertisol below 1 m depth in southeast Queensland. This study investigated the possibility that an absence of nitrification is allowing this ammonium to accumulate and persist over time, and examined the soil environmental characteristics that may be responsible for limiting nitrifying organisms. The possibility that anaerobiosis, soil acidity, soil salinity, low organic carbon concentrations, and/or an absence of active nitrifying microorganisms were responsible for limiting nitrification was examined in laboratory and field studies. The presence/absence of anaerobic conditions was determined qualitatively using a field test to give an indication of electron lability. In addition, an incubation study was conducted and soil environmental conditions were improved for nitrifying organisms by adjusting the pH from 4.4 to 7, adjusting the electrical conductivity from 1.6 to 0.5 dS/m, amending with a soluble carbon substrate at a rate of 500 mg/kg, and using microorganisms from the surface horizon to inoculate to the subsoil. Over a 180-day period no nitrification was detected in the control samples from the incubation study, indicating that an extremely low rate of nitrification is likely to be responsible for allowing ammonium to accumulate in this soil. Analysis of the effect of soil environmental conditions on nitrification revealed that anaerobic conditions did not exist at depth and that pH, EC, organic carbon, and inoculation treatments added in isolation had no effect on nitrification. However, when inoculum was added to the soil in combination with pH, a significant increase in nitrification was observed, and the greatest amount of nitrification was observed when inoculum, pH, and EC treatments were added in combination. It was concluded that the reason for the low rate of nitrification in this soil is primarily the absence of a significant population of active nitrifying microorganisms, which may have been unable to colonise the subsoil environment due to its acidic, and to a lesser extent, its saline environment.

Nitrate ammonification and its relationship to the accumulation of ammonium in a Vertisol subsoil

High concentrations of ammonium ( up to 270 kg N/ha) have been observed in a Vertisol soil below 1 m depth near Warra in south-east Queensland. This study examined the possibility that increased water movement into the subsoil after the removal of native vegetation, and a subsequent increase in periods of waterlogging, could have triggered nitrate ammonification and be responsible for the production of ammonium. Two incubation experiments were conducted to test this hypothesis. The first involved the incubation of repacked cores that had been amended with 30 mg N/kg of 5 atom% N-15 nitrate under low oxygen conditions for a period of 360 days. Over this time period the N-15 enrichment of the exchangeable ammonium fraction was monitored in order to detect any reduction of nitrate to ammonium. The second experiment involved the incubation of soil amended with 30 mg N/ kg of 5 atom% N-15 nitrate under waterlogged and low oxygen conditions for 75 days. During this period the redox potential of the soil was monitored using a field test to determine if reducing conditions would develop in this soil over a period of waterlogging, combined with the monitoring of any nitrate reduction to ammonium. The results of these experiments indicated that a small amount of nitrate ammonification (< 0.1 mg N/ kg) could be observed in the Warra subsoil, but that unless the rate of reduction were to significantly increase with time, this could not account for the accumulation of ammonium observed in the field. The environmental conditions that would make either dissimilatory or abiotic nitrate ammonification favourable were not observed to develop. Consequently, it has been concluded that the observed nitrate ammonification occurred via an assimilatory pathway. Due to the low rate of microbial activity in this subsoil it is considered unlikely that this process was responsible for the subsoil ammonium accumulation at Warra.

Patent policy, patent pools, and the accumulation of claims in sequential innovation

We present a dynamic model where the accumulation of patents generates an increasing number of claims on sequential innovation. We compare innovation activity under three regimes -patents, no-patents, and patent pools- and find that none of them can reach the first best. We find that the first best can be reached through a decentralized tax-subsidy mechanism, by which innovators receive a subsidy when they innovate, and are taxed with subsequent innovations. This finding implies that optimal transfers work in the exact opposite way as traditional patents. Finally, we consider patents of finite duration and determine the optimal patent length.

Activity in inferior parietal and medial prefrontal cortex signals the accumulation of evidence in a probability learning task.

In an uncertain environment, probabilities are key to predicting future events and making adaptive choices. However, little is known about how humans learn such probabilities and where and how they are encoded in the brain, especially when they concern more than two outcomes. During functional magnetic resonance imaging (fMRI), young adults learned the probabilities of uncertain stimuli through repetitive sampling. Stimuli represented payoffs and participants had to predict their occurrence to maximize their earnings. Choices indicated loss and risk aversion but unbiased estimation of probabilities. BOLD response in medial prefrontal cortex and angular gyri increased linearly with the probability of the currently observed stimulus, untainted by its value. Connectivity analyses during rest and task revealed that these regions belonged to the default mode network. The activation of past outcomes in memory is evoked as a possible mechanism to explain the engagement of the default mode network in probability learning. A BOLD response relating to value was detected only at decision time, mainly in striatum. It is concluded that activity in inferior parietal and medial prefrontal cortex reflects the amount of evidence accumulated in favor of competing and uncertain outcomes.

The accumulation of reproductive incompatibilities in African cichlid fish.

The rate at which different components of reproductive isolation accumulate with divergence time between species has only been studied in a limited, but growing, number of species. We measured premating isolation and hybrid inviability at four different ontogenetic stages from zygotes to adults in interspecific hybrids of 26 pairs of African cichlid species, spanning the entire East African haplochromine radiation. We then used multiple relaxed molecular clock calibrations to translate genetic distances into absolute ages to compare evolutionary rates of different components of reproductive isolation. We find that premating isolation accumulates fast initially but then changes little with increasing genetic distance between species. In contrast, postmating isolation between closely related species is negligible but then accumulates rapidly, resulting in complete hybrid inviability after 4.4/8.5/18.4 million years (my). Thus, the rate at which complete intrinsic incompatibilities arise in this system is orders of magnitude lower than rates of speciation within individual lake radiations. Together these results suggest divergent ecological adaptations may prevent populations from interbreeding and help maintain cichlid species diversity, which may be vulnerable to environmental degradation. By quantifying the capacity to produce viable hybrids between allopatric, distantly related lineages our results also provide an upper divergence time limit for the "hybrid swarm origin" model of adaptive radiation.

The accumulation of financial and social capital as a means to achieve a sustained competitive advantage for consumer co-operatives

By so far, scholars have discussed how the characteristics of consumer co-operatives (cooperative principles, values and the dual role of members as the users and owners) can potentially give them a competitive advantage over investor-owned firms (IOFs). In addition, concern for the community (as partly derived from locality and regionality) has been seen as a potential source of success for consumer co-operatives. On the other hand, the geographicbound purpose of consumer co-operation causes that consumer co-operative can be regarded as a challenging company form to manage. This is because, according to the purpose of consumer co-operation, co-operatives are obligated to 1) provide the owners with services and goods that are needed and do so at more affordable prices than their competitors do and/or 2) to operate in areas in which competitors do not want to operate (for example, because of the low profitability in certain area of business or region). Thus, consumer co-operatives have to operate very efficiently in order to execute this geographic-bound corporate purpose (e.g. they cannot withdraw from the competition during the declining stages of business). However, this efficiency cannot be achieved by any means; as the acceptance from the important regional stakeholders is the basic operational precondition and lifeline in the long run. Thereby, the central question for the survival and success of consumer co-operatives is; how should the consumer co-operatives execute its corporate purpose so it can be the best alternative to its members in the long run? This question has remained unanswered and lack empirical evidence in the previous studies on the strategic management of consumer cooperation. In more detail, scholars have not yet empirically investigated the question: How can consumer co-operatives use financial and social capital to achieve a sustained competitive advantage? It is this research gap that this doctoral dissertation aims to fulfil. This doctoral dissertation aims to answer the above questions by combining and utilizing interview data from S Group co-operatives and the central organizations in S Group´s network (overall, 33 interviews were gathered), archival material and 56 published media articles/reports. The study is based on a qualitative case study approach that is aimed at theory development, not theory verification (as the theory is considered as nascent in this field of study). Firstly, the findings of this study indicate that consumer co-operatives accumulate financial capital; 1) by making profit (to invest and grow) and 2) by utilizing a network-based organizational structure (local supply chain economies). As a result of financial capital accumulation, consumer co-operatives are able to achieve efficiency gains but also remain local. In addition, a strong financial capital base increases consumer co-operatives´ independence, competitiveness and their ability to participate in regional development (which is in accordance with their geographically bound corporate purpose). Secondly, consumer cooperatives accumulate social capital through informal networking (with important regional stakeholders), corporate social responsibility (CSR) behaviour and CSR reporting, pursuing common good, and interacting and identity sharing. As a result of social capital accumulation, consumer co-operatives are able to obtain the resources for managing; 1) institutional dependencies and 2) customer relations. By accumulating both social and financial capital through the above presented actions, consumer co-operatives are able to achieve sustained competitive advantage. Finally, this thesis provides useful ideas and new knowledge for cooperative managers concerning why and how consumer co-operatives should accumulate financial and social capital (to achieve sustained competitive advantage), while aligning with their corporate purpose.

Genotypic variations in the accumulation of Cd, Cu, Pb and Zn exhibited by six commonly grown vegetables

Metal contaminants in garden and allotment soils could possibly affect human health through a variety of pathways. This study focused on the potential pathway of consumption of vegetables grown on contaminated soil. Five cultivars each of six common vegetables were grown in a control and in a soil spiked with Cd, Cu, Pb and Zn. Highly significant differences in metal content were evident between cultivars of a number of vegetables for several of the contaminants. Carrot and pea cultivars exhibited significant differences in accumulated concentrations of Cd and Cu with carrot cultivars also exhibiting significant differences in Zn. Distinctive differences were also identified when comparing one vegetable to another, legumes (Leguminosae) tending to be low accumulators, root vegetables (Umbelliferae and Liliaceae) tending to be moderate accumulators and leafy vegetables (Compositae and Chenopodiaceae) being high accumulators. (c) 2006 Elsevier Ltd. All rights reserved.

Effects of N supply on the accumulation of photosynthetic pigments and photoprotectors in Gracilaria tenuistipitata (Rhodophyta) cultured under UV radiation

We have studied the effects of nitrate supply under photosynthetic active radiation (PAR) plus ultraviolet radiation (UVR) exposure on photosynthetic pigments (chlorophyll a and carotenoids), photoprotective UV screen mycosporine-like amino acids (MAAs), and photosynthetic parameters, including the maximum quantum yield (F(v)/F(m)) and electron transport rate (ETR) on the red agarophyte Gracilaria tenuistipitata. Apical tips of G. tenuistipitata were cultivated under ten different concentrations of NO(3)(-) for 7 days. It has been shown that G. tenuistipitata cultured under laboratory conditions has the ability to accumulate high amounts of MAAs following a nitrate concentration-dependent manner under PAR+UVR. Two MAAs were identified, shinorine and porphyra-334. The relative concentration of the first increased under high concentrations of nitrate, while the second one decreased. The presence of antheraxanthin is reported for the first time in this macro-algae, which also contains zeaxanthin, lutein, and beta-carotene. The accumulation of pigments, photoprotective compounds, and photosynthetic parameters of G. tenuistipitata is directly related to N availability. All variables decreased under low N supplies and reached constant maximum values with supplements higher than 0.5 mM NO(3)(-). Our results suggest a high potential to acclimation and photoprotection against stress factors (including high PAR and UVR) directly related to N availability for G. tenuistipitata.

Dietary restriction, caloric value and the accumulation of hepatic fat

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)