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All-out exercise may not impair all central nervous system processes, such as those related to visual-motor abilities, and may actually prove stimulatory to such tasks allowing athletes and sports conditioning specialists to develop strategies to take advantage of/mitigate the effects of such exercise on athletic performance. Despite research indicating that visual-motor abilities play a critical role in athletic performance, research has primarily focused on the effect of all-out exercise on processes along the motor pathway, such as resultant force production or simple cognitive tasks. Such research has neglected to investigate the effect of all-out exercise on visual tasks. When investigations on visual tasks are forthcoming, they focus on prolonged aerobic exercise, which is not the primary metabolic pathway for all, or even the majority of sports. Sixty untrained males (experimental group; N = 30, control group; N = 30) completed a standardised six-item baseline sports vision test battery and one week later, the experimental participants returned to undertake a 30-second Wingate anaerobic test (30-WAnT) immediately followed by the same test battery. Significant (P < 0.05) improvements were found in accommodation facility, saccadic eye movement, speed of recognition, peripheral awareness and hand-eye coordination (P < 0.001 for all), but not visual memory (P = 0.242) following the 30-WAnT. Although the mechanisms underlying these improvements in visual task performance have not yet been studied, this study suggests that simple anaerobic all-out exercise does not cause central- or brain-based fatigue impairing the oculomotor system but may rather provide "excitability" of the underlying motor cortex, motoneurons and/or corticofugal connections utilised in visual task response. It appears that the sweeping improvements in visual task performance elucidate the need for an intense anaerobic warm-up when training visual skills and when visual skills form an integral part of athletic performance. [ABSTRACT FROM AUTHOR]

The Gram-negative bacterium Vibrio cholerae is responsible for the severe diarrheal pandemic disease cholera, representing a major global public health concern. This pathogen transitions from aquatic reservoirs into epidemics in human populations, and has evolved numerous mechanisms to sense this transition in order to appropriately regulate its gene expression for infection. At the intersection of pathogen and host in the gastrointestinal tract lies the community of native gut microbes, the gut microbiome. It is increasingly clear that the diversity of species and biochemical activities within the gut microbiome represents a driver of infection outcome, through their ability to manipulate the signals used by V. cholerae to regulate virulence and fitness in vivo. A better mechanistic understanding of how commensal microbial action interacts with V. cholerae pathogenesis may lead to novel prophylactic and therapeutic interventions for cholera. Here, we review a subset of this burgeoning field of research. [ABSTRACT FROM AUTHOR]

In this study, potential of the air-diffusion channels to maintain the desired controlled atmosphere condition in the storage chambers was evaluated. The diffusion channels of different combination in length (60, 120, 180, 240 mm) and diameter (3, 6, 9, 12 mm) were installed in the storage chambers of 2 L capacity. Tomato samples (0.805 kg) were taken in the chambers and stored at 10°C. Oxygen concentration in the chambers was measured periodically until the end of storage period. The tomatoes were stored upto 40 days under the channel length of 180 mm and diameter of 9 mm with harvest-fresh appearance, better texture and colour. The experimental results showed that the oxygen concentration ranging from 7% to 15% was maintained depending on the channel length and its tendency was found directly proportional to the channel diameter and inversely related to the channel length. Simultaneously, respiration rate of tomato was determined by closed respiration system to facilitate working with diffusion channel model. A model was developed based on Fick's first law of gas diffusion to predict the channel length. The model was fitted to the experimental data and channel lengths were calculated theoretically in the ranges between 30 and 320 mm. The predicted channel lengths maintained the oxygen concentration between 4% and 16% irrespective of the channel diameters. The predicted results were in accordance with the experimental results. The model was very useful in predicting the diffusion channel length and establishing the controlled atmosphere condition for storage of tomatoes. [ABSTRACT FROM AUTHOR]

This paper reports the characterization of the polluting potential of sugarcane vinasse, the main wastewater from ethanol production. Compositional data from vinasse samples collected from sugarcane biorefineries were used to predict negative effects on the soil, water resources and crops potentially associated with fertirrigation, the primary final destination of vinasse in Brazil. High risks of soil salinization were associated with the land disposal of vinasse, as evidenced by the high levels of total dissolved solids (TDS; >4,000 mg L−1) and electrical conductivity (>6.7 dS m−1). The high TDS levels coupled with the high biodegradable organic content of vinasse (>14 g L−1) also favor organic overloading events, leading to local anaerobiosis conditions. Conversely, soil sodification should not be observed in areas fertirrigated with sugarcane vinasse, given the low Na concentrations (<66 mg L−1) relative to Mg (>145.1 mg L−1) and Ca (>458.4 mg L−1) levels. Priority pollutants (Cu, Cr, Ni, Pb and Zn) and phytotoxic elements (Al and Fe) were also found in the analyzed samples; however, relevant environmental impacts should not be associated with these particular constituents. Overall, the relatively simple methodology used herein could efficiently replace massive field data collection to provide a basic understanding of the fate of vinasse in the environment in order to highlight the priority points to be considered in the management of this effluent. In summary, the prompt implementation of treatment plants in distilleries, in addition to a continuous and broad compositional characterization of vinasse, is essential to guarantee its adequate reuse. [ABSTRACT FROM AUTHOR]

Denitrification results in the formation of two gaseous end-products: radiatively active greenhouse gas nitrous oxide (N2O) and radiatively inert di-nitrogen (N2). Measuring N2produced by soil microorganisms has historically been difficult because of interference by high background concentrations (780,840 ppm) of atmospheric N2.Here, we applied a new automated technique for simultaneous measurement of the denitrification end-products N2O and N2. We tested the hypothesis that the temperature response function (defined here as Q10) for N2O was greater than for N2under anaerobic conditions in the laboratory. The Q10for N2O was 2.0 and the Q10for N2was 1.4, indicating differences in sensitivity to temperature. Denitrified-N shifted towards N2O as temperature increased. While moisture strongly controls the relative abundance of denitrification end-products, additional experiments are needed to determine how a wider range of temperatures may affect N2O and N2. Results could enhance understanding of temperature controls on N2O production and consumption processes. [ABSTRACT FROM PUBLISHER]

Excess biological sludge, WAS, produced during activated sludge process is a growing problem for the utilities owing to the stringent regulations now imposed worldwide. One method of handling the excess sludge is to digest it, to reduce its amount and to stabilize it. Aerobic digestion is particularly suitable for nutrient treating plants as sludge should not be exposed to anaerobiosis since this will lead to release of accumulated phosphorus. A novel and patented ozone-assisted aerobic sludge digestion process (PCT/TR2010/000213) is shown to appreciably shorten the 15–30-day aerobic digestion period and the extent of solids destroyed. WAS samples were ozonated for different periods in Erlenmeyer flasks, once a day, on each of four consecutive days. Flasks were continuously aerated between ozone applications. The MLVSS, MLSS, COD and OUR parameters were measured routinely during the course of four days of digestion in order to optimize the process. As a result 22.6%, 40%, 75% and 84% MLVSS reductions were obtained at total ozone applications of 0.42, 0.64, 0.85 and 1.27 mg O3g−1MLSS, at the end of the fourth day. Hence, it became possible to save on contact time as well as achieving a bio-solids digestion far exceeding the standard aerobic process, which is 40–50% in 15–30 days, at the expense of a minimum of ozone dose. The developed process is deemed superior over side-stream ozonation where ozone is applied to the return activated sludge, RAS, line; in that it does not cause any reduction in active biomass amount maintained in the aeration tank. Conversely, reduction in active biomass concentration results in reduced treatment efficiency. [ABSTRACT FROM AUTHOR]

This study focused on biogas yields and biogas composition, especially methane production, during the anaerobic co-digestion of topinambour (Helianthus tuberosus L.) tuber through a laboratory-based biogas plant. A comparative study between the laboratory-based biogas plant and a biogas plant in practice revealed that the results from the laboratory experiments were realistic and transferable into practice. Biogas yields and the ultimate amounts of methane from topinambour co-digestion were much higher compared to other energy crops used as agrarian co-ferments, such as maize, sugar beets, and potatoes. Mean biogas yield was 1222 (±41) lN/kg-1 VS and mean methane yield was 74.5 (±2.5)%, and thus both parameters were markedly higher relative to other agricultural co-ferments. Based on mean yields of topinambour tubers in Germany of 6.4 - 12.2 t ha-1 dr.M. biogas yields from approximately 7800 - 15 000 m3 N ha-1 and methane yields from 5800 - 11 000 m3 N ha-1 can be calculated. Biogas manure from topinambour co-digestion was characterized by high amounts of total N (66.05 ± 3.1 mg g-1 dr.M.) and ammonia-N (45.27 ± 2.1 mg g-1 dr.M.). Amounts of total heavy metals of Pb, Cu, Ni, and Zn were far below the critical values of the German Biowaste Ordinance. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the responses of the oyster Crassostrea gigas to oxygen levels at subcellular and whole organism levels. Two experiments were carried out. The first experiment was designed to measure the clearance and oxygen consumption rates of oysters exposed at different concentrations of oxygen at 15, 20 and 25°C for 20 h. The goal of this first part was to estimate the hypoxic threshold for oysters below which their metabolism shifts towards anaerobiosis, by estimating the oxygen critical point (PcO2) at 15, 20 and 25°C. The second experiment was carried out to evaluate the metabolic adaptations to hypoxia for 20 days at three temperatures: 12, 15 and 20°C. The metabolic pathways were characterized by the measurement of the enzymes pyruvate kinase (PK) and phosphoenolpyruvate carboxykinase (PEPCK), the alanine and succinate content and the adenylate energy charge. Respiratory chain functioning was estimated by the measurement of the activity of the electron transport system (ETS). The values of PcO2 were 3.02±0.15, 3.43±0.20 and 3.28±0.24 mg O2 l-1 at 15, 20 and 25°C, respectively. In whole oysters, hypoxia involved the inhibition of PK whatever the temperature, but PEPCK was not stimulated. Succinate accumulated significantly only at 12°C and alanine at 12 and 15°C. A negative relationship between the PK activity and the alanine content was only found in hypoxic oysters. Finally, hypoxia increased significantly the activity of ETS. With high PcO2 values, the metabolic depression occurred quickly, showing that oysters had a low capacity to regulate their respiration when oxygen availability is reduced, particularly in the summer. [ABSTRACT FROM AUTHOR]

Low O2 stress to a varied extent affects almost all the organisms either throughout or at specific stages in their life cycle. Plants experience this stress generally in field conditions when flooding, submergence or waterlogging of roots/plants occurs. Low O2 availability during flooding stress results in enormous yield losses in variety of crops. There is overwhelming evidence indicating that adaptations to low O2 stress involves changes in molecular, biochemical, physiological, genetical and anatomical/morphological attributes in plants. Most plants respond to anaerobiosis by switching their respiration from the oxidative (involving complete oxidation of pyruvate into CO2) to the fermentation (involving incomplete oxidation of pyruvate into lactate/ethanol) pathway. Fermentation pathway-related proteins (such as pyruvate decarboxylase and alcohol dehydrogenase enzymes) have been characterized to a significant extent. However, attempts made in altering levels of pyruvate decarboxylase and alcohol dehydrogenase proteins in transgenic plants have not yielded significantly enhanced levels of low O2 /flooding stress tolerance as yet. Applying modern tools of transcriptome and proteome analysis, mechanism(s) responsible for low O2 /flooding stress tolerance phenotype are being addressed. Progress made in understanding plant responses to low O2 stress is herewith discussed. [ABSTRACT FROM AUTHOR]

In contrast to previous steady-state analyses of the 02-responsive transcriptome, here we examined the dynamics of the response to short-term anaerobiosis (2 generations) in both catabolite-repressed (glucose) and derepressed (galactose) cells, assessed the specific role that Msn2 and Msn4 play in mediating the response, and identified gene networks using a novel clustering approach. Upon shifting cells to anaerobic conditions in galactose medium, there was an acute (∼10 mm) yet transient (< 45 mm) induction of Msn2- and/or Msn4- regulated genes associated with the remodeling of reserve energy and catabolic pathways during the switch from mixed respiro-fermentative to strictly fermentative growth. Concomitantly, MCB- and SCB-regulated networks associated with the G1/S transition of the cell cycle were transiently down-regulated along with rRNA processing genes containing PAC and RRPE motifs. Remarkably, none of these gene networks were differentially expressed when cells were shifted in glucose, suggesting that a metabolically derived signal arising from the abrupt cessation of respiration, rather than O2 deprivation perse, elicits this "stress response." By ∼ 0.2 generation of anaerobiosis in both media, more chronic, heme-dependent effects were observed, including the down-regulation of Hapi-regulated networks, derepression of Roxi-regulated networks, and activation of Upc2-regulated ones. Changes in these networks result in the functional remodeling of the cell wall, sterol and sphingolipid metabolism, and dissimilatory pathways required for long-term anaerobiosis. Overall, this study reveals that the acute withdrawal of oxygen can invoke a metabolic state-dependent "stress response" but that acclimatization to oxygen deprivation is a relatively slow process involving complex changes primarily in heme-regulated gene networks. [ABSTRACT FROM AUTHOR]

Wetland rice fields are source of atmospheric methane. Methane is formed following reduction of carbon dioxide by hydrogen and through decarboxylation of acetate in anaerobic soils under reduced conditions. Methane production requires flow of carbon and electrons to microbial population of methanogens under reduced conditions in the strict absence of free oxygen. Application of or in-situ availability of terminal electron acceptors (oxidants) such as ferric iron or sulfate allows iron or sulfate reducers to successfully compete for substrates, hydrogen or acetate, with methanogens. This stops methane production. Electron acceptors also oxidize methane and reduce its emission. Since iron redox system plays a dominant role in tropical rice soils, which are rich in iron, the role of iron oxides and hydroxides as electron acceptor for controlling methane emission from wetland rice fields deserves more attention. For mitigating methane emission from wetland rice fields, ferric iron as a terminal electron-accepting agent, can either be added to the soil or regenerated in the soil by manipulating redox potential through soil and water management. Examples are given from recent literature illustrating the role of electron acceptors (ferric iron, sulfate, etc.) in reducing methane emission from submerged rice soils. The need for future research is also examined. [ABSTRACT FROM AUTHOR]

A new biotechnology on sludge granulation in upflow anaerobic sludge blanket (UASB) system was developed in this study. Methanol-cultured sludge for UASB inoculation demonstrated a beneficial effect on the granulation process. This new biotechnology accelerated the formation of embryonic granules in a laboratory-scale UASB reactor, and the granulation process reached its post-maturation stage in about 15-20 days ahead of the control reactor. There were no significant negative effects on COD removal and gas production due to this methanogen-enriched seed sludge. Methanol-cultured seed sludge for UASB inoculation could be an effective method to reduce the time required for UASB system start-up. [ABSTRACT FROM AUTHOR]

Provides information on a study conducted to determine whether wearing a Breathe Right nasal strip, with or without an athletic mouthpiece can affect anaerobic power output during anaerobic exercise. Information on the design of nasal strips; Methodology employed in this study; Findings of the study.

Using the leucine zipper domain of a small anaerobically induced bZIP transcription factor in a yeast two hybrid screen, anaerobically induced genes were identified. One peptide corresponds to an anaerobically induced IDS4-like protein that maybe involved in G-protein signaling. Surprisingly, another interacting peptide corresponds to a novel anaerobically induced 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase, designated ACO5. ACO5 harbours a leucine zipper and transcription is mainly induced in fruits and to a lesser extend in leaves. The role of ACO5 in the low oxygen response of tomato is discussed. [ABSTRACT FROM AUTHOR]