Increased temperature sensitivity of net DOC production from ombrotrophic peat due to water table draw-down.

The production and release of dissolved organic carbon (DOC) from peat soils is thought to be sensitive to changes in climate, specifically changes in temperature and rainfall. However, little is known about the actual rates of net DOC production in response to temperature and water table draw-down, particularly in comparison to carbon dioxide (CO2) fluxes. To explore these relationships, we carried out a laboratory experiment on intact peat soil cores under controlled temperature and water table conditions to determine the impact and interaction of each of these climatic factors on net DOC production. We found a significant interaction (P < 0.001) between temperature, water table draw-down and net DOC production across the whole soil core (0 to −55 cm depth). This corresponded to an increase in the Q10 (i.e. rise in the rate of net DOC production over a 10 °C range) from 1.84 under high water tables and anaerobic conditions to 3.53 under water table draw-down and aerobic conditions between −10 and − 40 cm depth. However, increases in net DOC production were only seen after water tables recovered to the surface as secondary changes in soil water chemistry driven by sulphur redox reactions decreased DOC solubility, and therefore DOC concentrations, during periods of water table draw-down. Furthermore, net microbial consumption of DOC was also apparent at − 1 cm depth and was an additional cause of declining DOC concentrations during dry periods. Therefore, although increased temperature and decreased rainfall could have a significant effect on net DOC release from peatlands, these climatic effects could be masked by other factors controlling the biological consumption of DOC in addition to soil water chemistry and DOC solubility. These findings highlight both the sensitivity of DOC release from ombrotrophic peat to episodic changes in water table draw-down, and the need to disentangle complex and interacting controls on DOC dynamics to fully understand the impact of environmental change on this system.

Acquisition of automatic imitation is sensitive to sensorimotor contingency

The associative sequence learning model proposes that the development of the mirror system depends on the same mechanisms of associative learning that mediate Pavlovian and instrumental conditioning. To test this model, two experiments used the reduction of automatic imitation through incompatible sensorimotor training to assess whether mirror system plasticity is sensitive to contingency (i.e., the extent to which activation of one representation predicts activation of another). In Experiment 1, residual automatic imitation was measured following incompatible training in which the action stimulus was a perfect predictor of the response (contingent) or not at all predictive of the response (noncontingent). A contingency effect was observed: There was less automatic imitation indicative of more learning in the contingent group. Experiment 2 replicated this contingency effect and showed that, as predicted by associative learning theory, it can be abolished by signaling trials in which the response occurs in the absence of an action stimulus. These findings support the view that mirror system development depends on associative learning and indicate that this learning is not purely Hebbian. If this is correct, associative learning theory could be used to explain, predict, and intervene in mirror system development.

The price of risk in construction projects: contingency approximation model (CAM)

Little attention has been focussed on a precise definition and evaluation mechanism for project management risk specifically related to contractors. When bidding, contractors traditionally price risks using unsystematic approaches. The high business failure rate our industry records may indicate that the current unsystematic mechanisms contractors use for building up contingencies may be inadequate. The reluctance of some contractors to include a price for risk in their tenders when bidding for work competitively may also not be a useful approach. Here, instead, we first define the meaning of contractor contingency, and then we develop a facile quantitative technique that contractors can use to estimate a price for project risk. This model will help contractors analyse their exposure to project risks; and help them express the risk in monetary terms for management action. When bidding for work, they can decide how to allocate contingencies strategically in a way that balances risk and reward.

In the intersection of the angles of a table, there is more truth than in all the tangle of muscles: Futurism as anti-humanist critique

The recent celebrations of the centenary of the publication of the Futurist manifesto led to a renewed discussion of the ideas and artworks of the Italian artists’ group. Jacques Rancière related the Futurist ethos with the modernist project of liberating art from representation. Franco ‘Bifo’ Berardi, in his post-Futurist manifesto, also identified a historical irony at play in the emptying out of Futurism’s promise: a liberated mechanical humanity did indeed materialize, in a global economic system premised on financial servitude to the future via debt. However, these models continue to assess Futurism against an unchallenged humanism, finding it either supporting ideals of freedom and human rights despite itself, or else lacking in these areas. But Futurism is potentially more relevant than ever not in spite of its anti-humanist agenda, precisely because of it. Tom McCarthy annexes not Futurist art but Futurist writing to an emerging object oriented ontology that seeks to challenge the primacy of the human. If Futurism is to be repurposed as a critical concept, it can only do so by countering the humanist myth the liberal subject that underlies the current cultural and political hegemony of neo-liberalism.

Contingency locus in ctsR of Listeria monocytogenes Scott A: a strategy for occurrence of abundant piezotolerant isolates within clonal populations

In a recent study we demonstrated that a high-hydrostatic-pressure-tolerant isolate of Listeria monocytogenes lacks a codon in the class 3 heat shock regulator gene ctsR. This mutation in the region that encodes four consecutive glycines was directly responsible for the observed piezotolerance, increased stress resistance, and reduced virulence. The aim of the present study was to determine whether mutations in ctsR are frequently associated with piezotolerance in L. monocytogenes. Wild-type cultures of L. monocytogenes were therefore exposed to 350 MPa for 20 min, and the piezotolerance of individual surviving isolates was assessed. This rendered 33 isolates with a stable piezotolerant phenotype from a total of 84 survivors. Stable piezotolerant mutants were estimated to be present in the initial wild-type population at frequencies of >10�5. Subsequent sequencing of the ctsR gene of all stable piezotolerant isolates revealed that two-thirds of the strains (i.e., n � 21) had mutations in this gene. The majority of the mutations (16 of 21 strains) consisted of a triplet deletion in the glycine-encoding region of ctsR, identical to what was found in our previous study. Interestingly, 2 of 21 mutants contained a codon insertion in this repeat region. The remaining three stable piezotolerant strains showed a 19-bp insertion in the glycine repeat region, a 16-bp insertion downstream of the glycine repeat area (both leading to frameshifts and a truncated ctsR), and an in-frame 114-bp deletion encoding a drastically shortened carboxy terminus of CtsR. In four instances it was not possible to generate a PCR product. A piezotolerant phenotype could not be linked to mutations in ctsR in 8 of 33 isolates, indicating that other thus-far-unknown mechanisms also lead to stable piezotolerance. The present study highlights the importance of ctsR in piezotolerance and stress tolerance of L. monocytogenes, and it demonstrates that short-sequence repeat regions contribute significantly to the occurrence of a piezotolerant and stress-tolerant subpopulation within L. monocytogenes cultures, thus playing an important role in survival.

Food marketing technology and contingency market valuation

Marketing activities are introduced into a rational expectations model of the food marketing system. The model is used to evaluate effects of alternative marketing technologies on the distribution of the benefits of contingency markets in agriculture. Benefits depend on two parameters: the cost share of farm inputs and the elasticity of substitution between farm and nonfarm inputs in food marketing. Over a broad spectrum of technologies, consumers are likely to be the net beneficiaries and farmers the net losers from the provision of contingency markets

The Choice of STIGA Table Tennis Blades : Evidence from China

The purpose of this paper is to investigate how individuals with different characteristics make their choice-decisions when consuming STIGA table tennis blades, which are combinations of various attributes, such as price, control, attack, etc. It is expected that the general trend of choice behavior on this special commodity can be, at least to some extent, revealed. Data were collected using questionnaires sent to registered members of a table tennis club in China. The questionnaires included information and questions about individuals’ monthly income levels, ages, technique styles, etc. A multinomial logit model was then applied to analyze factors determining Chinese consumers’ choice behavior on STIGA table tennis blades. The results indicated that the main element influencing Chinese consumers’ choice of STIGA ping-pong blades was the technique style and other variables did not seem to influence the choice of table tennis blades. These results might be explained by the limited sample size as well as unmeasured and immeasurable factors. Thus, a more extensive research is needed to be conducted in the future.