Guidelines,enthusiasms, uncertainty,and the limits to purchasing.

Recently government ministers have set out their vision of the future of purchasing. Ineffective treatments will be discarded and purchasing will be based on guidelines or protocols rather than activity. But have the advocates of this approach considered all the issues? This paper examines the challenges of balancing the desire for protocol based uniformity with the needs of individual patients, explores the extent to which existing purchasing structures can support this process, and questions whether such moves will actually lead to reduced costs. In each case it is concluded that oversimplistic analyses are likely to be misleading and that much of the current debate fails to recognise the complexity of health care.     

Discrete hierarchical organization of social group sizes

The 'social brain hypothesis' for the evolution of large brains in primates has led to evidence for the coevolution of neocortical size and social group sizes, suggesting that there is a cognitive constraint on group size that depends, in some way, on the volume of neural material available for processing and synthesizing information on social relationships. More recently, work on both human and non-human primates has suggested that social groups are often hierarchically structured. We combine data on human grouping patterns in a comprehensive and systematic study. Using fractal analysis, we identify, with high statistical confidence, a discrete hierarchy of group sizes with a preferred scaling ratio close to three: rather than a single or a continuous spectrum of group sizes, humans spontaneously form groups of preferred sizes organized in a geometrical series approximating 3-5, 9-15, 30-45, etc. Such discrete scale invariance could be related to that identified in signatures of herding behaviour in financial markets and might reflect a hierarchical processing of social nearness by human brains.     

Research on contaminant sources identification of uncertainty water demand using genetic algorithm

Urban water supply network is easily affected by intentional or occasional chemical and biological pollution, which threatens the health of consumers. In recent years, drinking water contamination happens occasionally, which seriously harms social stabilization and safety. Placing sensors in water supply pipes can monitor water quality in real time, which may prevent contamination accidents. However, how to reversely locate pollution sources through the detecting information from water quality sensors is a challengeable issue. Its difficulties lie in that limited sensors, massive pipe network nodes and dynamic water demand of users lead to the uncertainty, large-scale and dynamism of this optimization problem. This paper mainly studies the uncertainty problem in contaminant sources identification (CSI). The previous study of CSI supposes that hydraulic output (e.g., water demand) is known. Whereas, the inherent variability of urban water consumption brings an uncertain problem that water demand presents volatility. In this paper, the water demand of water supply network nodes simulated by Gaussian model is stochastic, and then being used to solve the problem of CSI, simulation–optimization method finds the minimum target of CSI and concentration which meet the simulation value and detected value of sensors. This paper proposes an improved genetic algorithm to solve the CSI problem under uncertainty water demand and comparative experiments are placed on two water distribution networks of different sizes.     

Fibronectin organization under and near cells

Polymerization of soluble fibronectin molecules results in fibres that are visible as networks using fluorescently labelled fibronectin protomers or by antibody labelling. Displacement of fibres composed of modified protomers in living cells provides information regarding matrix structure, organization, and movement. A static analysis of fibronectin structures and patterns of organization provide insight into their reorganization during adhesion and motility. Confocal microscopy and atomic force microscopy (AFM) reveal fibronectin-containing networks aligned in arrays perpendicular to the retracting cell edge and in apparently disordered networks of fibres under the cell. The change in patterns suggests a reorganization of fibronectin from disordered arrays used for adhesion into ordered arrays during movement of the cell. Comparison of confocal images with corresponding AFM images confirms that the fibres left on the surface as the cell moves away do contain fibronectin. The orientation of these fibres relative to the tail (uropod) and the receding edges of the cell leads us to propose that cells generate a force on the fibres that exceeds the adhesion force of the fibres to the surface causing them to pull fibronectin fibres into straight arrays. However, when the fibres are parallel to the direction of pull, the fibres remain attached to the surface. The data supports the hypothesis that disorganized, linear fibres are the product of Fn polymerization induced by the cell beneath it and serve to adhere the cell to the substrate as the cell spreads, whereas arrays of fibres found outside the cell are formed as existing fibrils and reorganize during cell motility.Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.     

A preliminary study of kinship and social organization in a semi-free-ranging group ofLemur catta

From long-term studies of a number of anthropoid species, many investigators have shown that kinship affinities affect social relationships. Factors such as proximity, social grooming, dominance rank, and mating patterns have been shown to be related to kinship. In this paper, we report the results of a preliminary study of the social organization of a group of prosimians (Lemur catta) in which individuals were identified and kinship affinities were known. We found that close matrilineal kin preferred to groom one another and to remain in close proximity more than did nonkin and distantly related animals. Furthermore, no copulations were observed within matrilines. These results are similar to those found in a number of species of anthropoids. This research was conducted on a semi-free-ranging group at the Duke University Primate Facility, Durham, North Carolina.     

Systems analysis of cellular networks under uncertainty

Besides the often-quoted complexity of cellular networks, the prevalence of uncertainties about components, interactions, and their quantitative features provides a largely underestimated hallmark of current systems biology. This uncertainty impedes the development of mechanistic mathematical models to achieve a true systems-level understanding. However, there is increasing evidence that theoretical approaches from diverse scientific domains can extract relevant biological knowledge efficiently, even from poorly characterized biological systems. As a common denominator, the methods focus on structural, rather than more detailed, kinetic network properties. A deeper understanding, better scaling, and the ability to combine the approaches pose formidable challenges for future theory developments.     

Genomic organization of human histo-blood group ABO genes

We have isolated human genomic DNA clones encompassing 30 kbpof the histo-blood group ABO locus. The locations of the exonshave been mapped and the nucleotide sequences of the exon-intronboundaries have been determined. The human ABO genes consistof at least seven exons, and the coding sequence in the sevencoding exons spans over 18 kb of the genomic DNA. The exonsrange in size from 28 to 688 bp, with most of the coding sequencelying in exon 7. ABO genomic glycosyltransferase histo-blood group transfusion     

The effects of foraging demand on social interactions in a laboratory group of Bonnet Macaques

The relationship between foraging demand and social behavior was experimentally studied in a laboratory group of bonnet macaques. Fourteen adult animals were housed in a large outdoor enclosure containing three shallow gravelfilled circular containers that served as the foraging sites. During the experimental foraging sessions raisins were placed in the containers and the social and foraging behaviors of the group were observed for 50 min following the distribution of raisins. Three types of foraging conditions were inter-spersed with one another on different test days: (1) surface load— raisins placed on top of the gravel; (2) buried load— raisins hidden underneath the gravel; and (3) sham load— no raisins placed at the foraging sites. Three basic foraging patterns, defined along a temporal dimension, were seen. One group of animals completed 50% of their total foraging by the end of the first 15 min. A second group foraged more steadily through the session. A third group foraged late, completing 50% of their foraging during the last half of the session. The foraging patterns were similar in the buried and surface condition, although the patterns were more compressed during the surface condition. More aggression and more avoidance of other animals occurred in the buried condition than in the surface condition. Very little foraging occurred during the sham condition. There was no clear relationship between the patterns of interaction during foraging and nonforaging observation sessions. The results suggest the value of manipulative laboratory studies in examining the relationship between ecological variables and social behavior in nonhuman primates.     

Developments of the Price equation and natural selection under uncertainty

Many approaches to the study of adaptation, following Darwin, centre on the number of offspring of individuals. Population genetics theory makes clear that predicting gene frequency changes requires more detailed knowledge, for example of linkage and linkage disequilibrium and mating systems. Because gene frequency changes underlie adaptation, this can lead to a suspicion that approaches ignoring these sophistications are approximate or tentative or wrong. Stochastic environments and sexual selection are two topics in which there are widespread views that focusing on number of offspring of individuals is not enough, and that proper treatments require the introduction of further details, namely variability in offspring number and linkage disequilibrium, respectively. However, the bulk of empirical research on adaptation and a great deal of theoretical work continue to employ these approaches. Here, a new theoretical development arising from the Price equation provides a formal justification in very general circumstances for focusing on the arithmetic average of the relative number of offspring of individuals.     

Efficiency of a visual system under conditions of uncertainty of the appearance of a moving object

The effect of uncertainty of a moving object appearance in the noise field upon the coefficient efficiency, we studied. At short durations of presentation (40-80 msec) and high level of external noise, this effect was maximal: magnified 100 times. The efficiency coefficient dependence on the duration of a moving object presentation was shown to be characterized by two maximums. The position of minimum situated between these two maximums was found to be independent of either presence or absence of uncertainty of a number of parameters: such as initial position of the object the image, time of its appearance, noise level, velocity and direction of the movement, and has a latency approximately 120 sec. A functional model of the observed phenomena, has been proposed.     

Managing uncertainty: information and insurance under the risk of starvation

In an uncertain world, animals face both unexpected opportunities and danger. Such outcomes can select for two potential strategies: collecting information to reduce uncertainty, or insuring against it. We investigate the relative value of information and insurance (energy reserves) under starvation risk by offering model foragers a choice between constant and varying food sources over finite foraging bouts. We show that sampling the variable option (choosing it when it is not expected to be good) should decline both with lower reserves and late in foraging bouts; in order to be able to reap the reduction in uncertainty associated with exploiting a variable resource effectively, foragers must be able to afford and compensate for an initial increase in the risk of an energetic shortfall associated with choosing the option when it is bad. Consequently, expected exploitation of the varying option increases as it becomes less variable, and when the overall risk of energetic shortfall is reduced. In addition, little activity on the variable alternative is expected until reserves are built up early in a foraging bout. This indicates that gathering information is a luxury while insurance is a necessity, at least when foraging on stochastic and variable food under the risk of starvation.     

Comparative genetic organization of incompatibility group P degradative plasmids.

Plasmids that encode genes for the degradation of recalcitrant compounds are often examined only for characteristics of the degradative pathways and ignore regions that are necessary for plasmid replication, incompatibility, and conjugation. If these characteristics were known, then the mobility of the catabolic genes between species could be predicted and different catabolic pathways might be combined to alter substrate range. Two catabolic plasmids, pSS50 and pSS60, isolated from chlorobiphenyl-degrading strains and a 3-chlorobenzoate-degrading plasmid, pBR60, were compared with the previously described IncP group (Pseudomonas group P-1) plasmids pJP4 and R751. All three of the former plasmids were also members of the IncP group, although pBR60 is apparently more distantly related. DNA probes specific for known genetic loci were used to determine the order of homologous loci on the plasmids. In all of these plasmids the order is invariant, demonstrating the conservation of this "backbone" region. In addition, all five plasmids display at least some homology with the mercury resistance transposon, Tn501, which has been suggested to be characteristic of the beta subgroup of the IncP plasmids. Plasmids pSS50 and pSS60 have been mapped in detail, and repeat sequences that surround the suspected degradation genes are described.     

Structural-functional organization of the incompatibility group P plasmid pBS221

Plasmid pBS221 was physically mapped for restriction endonucleases EcoRI, BamHI, BglII, HindIII. The regions essential for the plasmid existence and participating in replication (oriV trfA*) and mobilization (mob) were cloned. The tet determinant and oriV trfA* regions were localized on the physical map of the plasmid. A DNA sequence homologous to genes of Tn501 mer operon was detected in this plasmid. The studies on homology of plasmids RP4 (IncP alpha), R751 (IncP beta) and pBS221 plasmid suggest that the latter belongs to the IncP beta subgroup.     

Paramagnetic spin label interactions with the envelope of a group A arbovirus. Lipid organization

Electron paramagnetic resonance observations were made on nitroxide spin-labeled molecules which were bound to the TC-83 vaccine strain of Venezuelan equine encephalomyelitis virus. Paramagnetic resonance parameters derived from the observations and their dependence on sample temperature were similar but not identical to those which have been reported for these labels dissolved in lipid bilayer membranes of mammalian and bacterial origin. The data are consistent with the existence of a bilayer lipid structure in the virion envelope which has a mechanical rigidity substantially greater than that of bilayers in cellular membranes. A model is presented which assumes the location of the lipid bilayer outside the nucleoprotein capsid and inside a spherical layer of envelope proteins. The model is in accord with Harrison's X-ray diffraction results for Sindbis virus. The model is discussed in terms of its implications with respect to the role played by lipid in viral maturation and infectivity.     

Significance of motivation balance for a choice of dog's behavior under conditions of environmental uncertainty

Two experimental models with a choice between two reinforcements were used for assessment of individual typological features of dogs. In the first model dogs were given the choice of homogeneous food reinforcements: between less valuable constantly delivered reinforcement and more valuable reinforcement but delivered with low probabilities. In the second model the dogs had the choice of heterogeneous reinforcements: between performing alimentary and defensive reactions. Under conditions of rise of uncertainty owing to a decrease in probability of getting the valuable food, two dogs continued to prefer the valuable reinforcement, while the third animal gradually shifted its behavior from the choice of a highly valuable but infrequent reward to a less valuable but easily achieved reinforcement. Under condition of choice between the valuable food reinforcement and avoidance of electrocutaneous stimulation, the first two dogs preferred food, whereas the third animal which had been previously oriented to the choice of the low-valuable constant reinforcement, steadily preferred the avoidance behavior. The data obtained are consistent with the hypothesis according to which the individual typological characteristics of animals's (human's) behavior substantially depend on two parameters: extent of environmental uncertainty and subjective features of reinforcement assessment.