'Round the Clock Observations of the Q0957+561 A,B Gravitationally Lensed Quasar

An observing campaign with 10 participating observatories has undertaken to monitor the optical brightness of the Q0957 gravitationally lensed quasar for 10 consecutive nights in January 2000. The resulting A image brightness curve has significant brightness fluctuations and makes a photometric prediction for the B image light curve for a second campaign planned for 12-21 March 2001. The ultimate purpose is to determine the gravitational lens time delay to a fraction of an hour, and to seek evidence for rapid microlensing.Comment: 8 pages, AASTeX 4.0, accepted by the Astrophysical Journa

Temperate Forage Grass-Legume Mixtures: Advances And Perspectives

The paper summarises some of the advances which have been made a) in increasing understanding of the grass-legume association, especially grass-white clover, so that the association can be more predictably exploited and b) in overcoming limitations in the use of such mixtures. The contribution which forage legumes make to the N economy of mixtures is reviewed with estimates approaching 400 kg N ha-1 for some. Uptake by grass of legume- derived N (N transfer) reduces soil mineral N levels and increases the proportion of fixed N in the total legume N relative to legume monoculture. Although N transfer also causes inconsistent contribution of legume to mixed swards, models of the effect of legume derived N on the interaction between grass and legume are helping to predict likely grass-legume balance, even when grazed. The higher nutritive value and intake of legumes relative to grass is due to a range of factors including faster rate of particle breakdown, faster digestion in the rumen, more non- ammonium N reaching the small intestine and higher efficiency of energy utilization although efficiency of N utilization is lower. Poor utilization is not an issue with birdsfoot trefoil and sainfoin due to their herbage having a high content of condensed tannins which protect protein from degradation in the rumen. Breeding programmes using conventional and biotechnological methods are aiming to improve nutritive value such as increasing protein quality and introducing condensed tannins into clovers and lucerne. Breeding of legumes to reduce antiquality factors, such as bloat, is underway. Breeding to reduce oestrogenic effects has been successful in red clover and subclover. Advances are leading to improved legume consistency in mixture including improvement in tolerance to biotic and environmental stress by breeding and increased understanding of the role of companion grasses. Research which underpins management techniques to improve predictability of grass-legume balance is also discussed, including the positive and negative role of the grazing animal. The potential and limitations of grass-legume swards to reduce N loss, including NO3 leaching, in whole farm systems is evaluated where grass/white clover can reduce leaching by 50% compared with a high fertilizer N system at only 20% reduction in output. Other factors which may result in increased reliance on forage legumes, in addition to the improvements in forage legumes resulting from research, include de-intensification policy decisions to reduce stocking rates, increased uptake of organic farming, increased cost of N fertilizer relative to commodity prices. Shared research effort between countries is advocated to supply adequate resources to solve some of the remaining problems in grass/legume associations and effective technology transfer should include development of decision support systems due to the complexity of the association

Nitrogen and Phosphorus Losses in Runoff on Beef Production Systems

In West Europe countries between 37 and 82% of the nitrogen (N) and between 27 and 38% of the phosphorus (P) reaching water sources come from agriculture and a strong correlation between the number of animals per area unit and N and P contribution to waters has been shown (Issermann, 1990). There are few data about the environmental impact of beef production systems in Southern Chile. The objective of this experiment was to quantify N and P losses in runoff (surface and subsurface) with two different stocking rates in Southern Chile

Current challenges facing the assessment of the allergenic capacity of food allergens in animal models

Food allergy is a major health problem of increasing concern. The insufficiency of protein sources for human nutrition in a world with a growing population is also a significant problem. The introduction of new protein sources into the diet, such as newly developed innovative foods or foods produced using new technologies and production processes, insects, algae, duckweed, or agricultural products from third countries, creates the opportunity for development of new food allergies, and this in turn has driven the need to develop test methods capable of characterizing the allergenic potential of novel food proteins. There is no doubt that robust and reliable animal models for the identification and characterization of food allergens would be valuable tools for safety assessment. However, although various animal models have been proposed for this purpose, to date, none have been formally validated as predictive and none are currently suitable to test the allergenic potential of new foods. Here, the design of various animal models are reviewed, including among others considerations of species and strain, diet, route of administration, dose and formulation of the test protein, relevant controls and endpoints measured

Hippocampal - diencephalic - cingulate networks for memory and emotion: An anatomical guide

This review brings together current knowledge from tract tracing studies to update and reconsider those limbic connections initially highlighted by Papez for their presumed role in emotion. These connections link hippocampal and parahippocampal regions with the mammillary bodies, the anterior thalamic nuclei, and the cingulate gyrus, all structures now strongly implicated in memory functions. An additional goal of this review is to describe the routes taken by the various connections within this network. The original descriptions of these limbic connections saw their interconnecting pathways forming a serial circuit that began and finished in the hippocampal formation. It is now clear that with the exception of the mammillary bodies, these various sites are multiply interconnected with each other, including many reciprocal connections. In addition, these same connections are topographically organised, creating further subsystems. This complex pattern of connectivity helps explain the difficulty of interpreting the functional outcome of damage to any individual site within the network. For these same reasons, Papez’s initial concept of a loop beginning and ending in the hippocampal formation needs to be seen as a much more complex system of hippocampal–diencephalic–cingulate connections. The functions of these multiple interactions might be better viewed as principally providing efferent information from the posterior medial temporal lobe. Both a subcortical diencephalic route (via the fornix) and a cortical cingulate route (via retrosplenial cortex) can be distinguished. These routes provide indirect pathways for hippocampal interactions with prefrontal cortex, with the preponderance of both sets of connections arising from the more posterior hippocampal regions. These multi-stage connections complement the direct hippocampal projections to prefrontal cortex, which principally arise from the anterior hippocampus, thereby creating longitudinal functional differences along the anterior–posterior plane of the hippocampus

Is the meiofauna a good indicator for climate change and anthropogenic impacts?

Our planet is changing, and one of the most pressing challenges facing the scientific community revolves around understanding how ecological communities respond to global changes. From coastal to deep-sea ecosystems, ecologists are exploring new areas of research to find model organisms that help predict the future of life on our planet. Among the different categories of organisms, meiofauna offer several advantages for the study of marine benthic ecosystems. This paper reviews the advances in the study of meiofauna with regard to climate change and anthropogenic impacts. Four taxonomic groups are valuable for predicting global changes: foraminifers (especially calcareous forms), nematodes, copepods and ostracods. Environmental variables are fundamental in the interpretation of meiofaunal patterns and multistressor experiments are more informative than single stressor ones, revealing complex ecological and biological interactions. Global change has a general negative effect on meiofauna, with important consequences on benthic food webs. However, some meiofaunal species can be favoured by the extreme conditions induced by global change, as they can exhibit remarkable physiological adaptations. This review highlights the need to incorporate studies on taxonomy, genetics and function of meiofaunal taxa into global change impact research

Evolución de un sistema de lodos activos sin aporte de alimentación

[ES] En el presente trabajo se ha estudiado el comportamiento de una unidad de lodos activos durante un periodo de tiempo de 21 días durante los cuales no se realizó aporte alguno de materia orgánica al sistema. Se ha observado un descenso en la biomasa presente en el reactor, el cual puede estar relacionado con la degradación de los componentes intracelulares como consecuencia del metabolismo endógeno, así como con la disminución producida en el valor de los sólidos durante los cuatro primeros días. La degradación de los lodos durante el tiempo en que se lleva a cabo el ensayo, produce un descenso de la actividad respiratoria y enzimática de los microorganismos presentes en el sistema.Coello Oviedo, MD.; Sales Márquez, D.; Quiroga Alonso, JM. (2003). Evolución de un sistema de lodos activos sin aporte de alimentación. Ingeniería del agua. 10(1):11-17. https://doi.org/10.4995/ia.2003.2572OJS1117101APHA; AWWA; WPCF (1989). Métodos Normalizados. Para el análisis de aguas potables y residuales. Editorial Díaz de Santos, S. A., Edición en español (1990).Awong, J., Bitton, G., Koopman, B. (1985). ATP, Oxigen uptake rate and INT-dehydrogenase activity of actinomycete foams. Water Res., 7(19): 917-921.Baldwin, H. And Chandler, G. (1966). Freshwater Biology. Edmonson, Washington, D.C.Benedek, P., Farkas, P., Literathy P. (1972). Kinetics of aerobic sludge stabilization. Water Res., 6, 91-97.Curds C. R. (1982). British and other freshwater Ciliated Protozoa. Part I. Cambridge University Press, London.Curds, C.R., Gates, M.A. and Roberts, D. McL. (1983). ). British and other freshwater Ciliated Protozoa. Part II. Cambridge University Press, London.Gaudy A. F. Jr, Ramanathan, M., Yong, P.Y. and Degeare, T.V. (1970). Studies of the operational stability of the extend aeration process. J. Water Poll. Control Fed., 42, 165-170.Griebe, T., Shaule, G., Wuertz, S. (1997). Determination of microbial respiratory and redox activity in activated sludge. Journal of Industrial Microbiology & Biotechnology 19, 118-122.Horan N. J. and Shanmugan, P. (1986). Effects of starvation ad nutrient depletion on the settling properties of activated sludge. Wat. Res. 20, 661-666.Jenkins, C.J. and Mavinic, D.S. (1989). Anoxic.aerobic digestion of waste activated sludge :Part I- Solids reduction and digested sludge characteristics. Environ. Technol. Lett., 10, 355-370.Kim, M. H. and Hao, O.J. (1990). Comparison of activated sludge stabilization under aerobic or anoxic conditions. J. Water Pollut. Control Fed., 62, 160-168.Kjelleberg, S., Hermansson M., Marden, P., Jones, G. W. (1987). The transient phase between growth and non-growth of 4heterotrophic bacteria, with emphasis on marine environment. Ann. Rev. Microbiol., 41, 25-49.Lee, J.J., Hunter S.H. and Bovee E. C. (1985). An illustrated guide to the protozoa. Society of Protozoologists. Lawrence, Kansas.Mason C. A., Bryers, J.D. and Hamer, G. (1986). Activity, death and lysis during microbial growth in a chemostat. Chem Eng. Commun., 45, 163-176.Mason, C.A., Hamer, G. (1987). Crytic growth in Klebsiella pneumoniae. Appl. Environ. Biotech., 25, 577-584.Matin, A. (1979) Microbial regulatory mechanism at low nutrient concentrations as studied in chemostat. In:Strategies of Microbial Life in Extreme Environments, Shilo M. (Ed), pp 323-339, Dahhlem KMetcalf & Eddy. Inc. Wastewater Engineering. Collection and pumping of wastewater. G. Tchobanoblous Ed. MacGraw-Hill, Inc., Nueva York, 1981.Reddy, M.P., Gaudy A. F. Jr., and Mannickam, T. (1983). Total oxidation process using and aerobic digestor as a source of recicle sludge. Chem. Eng. Commun., 23, 137-150.Roszak D.B. y Colwell R.R. (1987). Survival strategies of bacteria in the natural environment. Microbiol., 41, 25-49.Schaule, G; Flemming, H-C; Ridgway, H.F.; (1993). Use of 5-Cyano-2,3-Ditolyl Tetrazolium Chloride for Quantifying Planktonic and Sessile Respiring Bacteria in Drinking Water. Applied and Environmental Microbiology 11 (59): 3850-3857.Teuber, M. and Brodish, K. E. V. (1977). Enzymatic activities of activated sludge. Eur. J. Appl. Microbiol., 4, 185-194.Urbain, V, Pys, E., Block, J.C., Manem, J. (1993). Composition and activity of activated sludge under starvation conditions. Environmental Technology, 14:731-740

Visuospatial bootstrapping:Binding useful visuospatial information during verbal working memory encoding does not require set-shifting executive resources

Immediate serial recall of digits is better when the digits are shown by highlighting them in a\ud familiar array, such as a phone keypad, compared to presenting them serially in a single\ud location; a pattern referred to as ‘visuospatial bootstrapping’. This pattern implies the\ud establishment of temporary links between verbal and spatial working memory, alongside\ud access to information in long term memory. However, the role of working memory control\ud processes like those implied by the ‘Central Executive’ in bootstrapping has not been directly\ud investigated. Here we report a study addressing this issue, focusing on executive processes of\ud attentional shifting. Tasks in which information has to be sequenced are thought to be heavily\ud dependent on shifting. Memory for digits presented in keypads versus single locations was\ud assessed under two secondary task load conditions, one with and one without a sequencing\ud requirement, and hence differing in the degree to which they invoke shifting. Results\ud provided clear evidence that multimodal binding (visuospatial bootstrapping) can operate\ud independently of this form of executive control process

Biosensor immunoassay for traces of hazelnut protein in olive oil

The fraudulent addition of hazelnut oil to more expensive olive oil not only causes economical loss but may also result in problems for allergic individuals as they may inadvertently be exposed to potentially allergenic hazelnut proteins. To improve consumer safety, a rapid and sensitive direct biosensor immunoassay, based on a highly specific monoclonal antibody, was developed to detect the presence of hazelnut proteins in olive oils. The sample preparation was easy (extraction with buffer); the assay time was fast (4.5 min only) and the limit of detection was low (0.08 μg/g of hazelnut proteins in olive oil). Recoveries obtained with an olive oil mixed with different amounts of a hazelnut protein containing hazelnut oil varied between 93% and 109%