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Deciduous trees remobilize the nitrogen in senescing leaves during the process of autumn colouration, which in many species is associated with increased concentrations of anthocyanins. Archetti1 and Hamilton and Brown2 observed that autumn colouration is stronger in tree species facing a high diversity of specialist aphids. They proposed a coevolution theory that the bright colours in autumn might provide an honest signal of defence commitment, thus deterring migrant aphids from settling on the leaves. So far, there have been very few (...) experimental results to support the hypothesis, and tree commitment to phenolics‐based defences has not shown direct protection against aphids. Predators and parasitoids have been found to be the major controllers of arboreal aphids. Indirect defences involve the emission of attractive volatile compounds that enhance the effectiveness of carnivorous enemies. The indirect defence hypothesis is presented to explain low aphid diversity on tree species that are green during autumn. The hypothesis suggests that green foliage can continue to produce herbivore‐inducible plant volatiles and maintain volatile‐based indirect plant defences against aphids until leaf abscission. BioEssays 30:889–896, 2008. © 2008 Wiley Periodicals, Inc. (shrink)

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Stationary spacetimes containing a black hole have several properties akin to those of atoms. For instance, such spacetimes have only three classical degrees of freedom, or observables, which may be taken to be the mass, the angular momentum, and the electric charge of the hole. There are several arguments supporting a proposal originally made by Bekenstein that quantization of these classical degrees of freedom gives an equal spacing for the horizon area spectrum of black holes. We review some of these (...) arguments and introduce a specific Hamiltonian quantum theory of black holes. Our Hamiltonian quantum theory gives, among other things, a discrete spectrum for the classical observables, and it produces an area spectrum which is closely related to Bekenstein's proposal. We also present a foamlike model of horizons of spacetime. In our model spacetime horizon consists of microscopic Schwarzschild black holes. Applying our Hamiltonian approach to this model we find that the entropy of any horizon is one quarter of its area. (shrink)

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The book deals with the reception and critique of symbolic logic among German-speaking philosophers at the turn of the 20th century. The first part discusses the period from the late 1870s up to the end of the 19th century. The main issue is the arrival of the Boolean algebra of logic in Germany and Austria. It examines also the reasons why Gottlob Frege was so unsuccessful in his attempts to draw the attention of philosophers to his logicist programme. The second (...) part deals with the first two decades of the 20th century. Its main topic of inquiry is the reception of Bertrand Russell's and Louis Couturat's ideas in the German-speaking world. In particular, it concentrates on the relationship between Russell and neo-Kantians. (shrink)

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We study the computational complexity of the model checking problem for quantifier-free dependence logic ${(\mathcal{D})}$ formulas. We characterize three thresholds in the complexity: logarithmic space (LOGSPACE), non-deterministic logarithmic space (NL) and non-deterministic polynomial time (NP).

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Fundamental assumptions behind qualitative modelling are critically considered and some inherent problems in that modelling approach are outlined. The problems outlined are due to the assumption that a sufficient set of symbols representing the fundamental features of the physical world exists. That assumption causes serious problems when modelling continuous systems. An alternative for intelligent system building for cases not suitable for qualitative modelling is proposed. The proposed alternative combines neural networks and quantitative modelling.

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The paper discusses neo-Kantian commentaries on Russell's views on logic and the philosophy of mathematics at the beginning of the twentieth century. Although Russell and the neo-Kantians had similar philosophical interests at this time, their views were usually incompatible. First, I examine the differences between Russell's A Critical Exposition of the Philosophy of Leibniz and Cassirer's Leibniz' System in seinen wissenschaftlichen Grundlagen. Second, I discuss the critiques of the logicist programme presented by the neo-Kantians Paul Natorp, Ernst Cassirer and Jonas (...) Cohn. They argued that Russell's attempt to deduce the number concept from the class concept is a petitio principii. Russell replied that the sense in which every object is ‘one’ must be distinguished from the sense in which ‘one’ is a number. I claim that Russell was wrong in dismissing the neo-Kantian argument as an elementary error. Neo-Kantians understood the logicist definition of number in terms of the neo-Kantian movement to which they belonged; that is to say, although the notion ‘a class with one object’ does not presuppose the number ‘one’ if one accepts the logicist definition of number, it will presuppose it if one advocates a neo-Kantian theory of number. (shrink)

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Contemporary semantic theories can be classified along two dimensions: (i) the way and time-course in which contextual factors influence sentence truth-conditions; and (ii) whether and to what extent comprehension involves sensory, motor and emotional processes. In order to explore this theoretical space, our ERP study investigates the time-course of the interaction between the lexically specified telic component of a noun (the function of the object to which the noun refers to, e.g., a funnel is generally used to pour liquids into (...) containers) and an ad-hoc affordance contextually induced by the situation described in the discourse. We found that, if preceded by a neutral discourse context, a verb incongruent with the noun’s telic component as in “She uses the funnel to hang her coat” elicited an enhanced N400 compared to a congruent verb as in “She uses the funnel to pour water into a container”. However, if the situation introduced in the preceding discourse induced a new function for the object as an ad-hoc affordance (e.g., the funnel is glued to the wall and the agent wants to hang the coat), we observed a crossing-over regarding the direction of the N400 effect: comparing the ad-hoc affordance-inducing context with the neutral context, the N400 for the incongruent verb was significantly reduced, whereas the N400 for the congruent verb was significantly enhanced. We explain these results as a consequence of the incorporation of the contextually triggered ad-hoc affordance into the meaning of the noun. Combining these results with an analysis of semantic similarity values between test sentences and contexts, we argue that one possibility is that the incorporation of an ad-hoc affordance may be explained on the basis of the mental simulation of concurrent motor information. (shrink)

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This Correspondence argues in response to Coolsaet et al. (2024) that there is an important role to play for stance-independent justice discussions that are not tied to specific social, political or critical perspectives. These can be valuable for climate research audiences, but also as a basis upon which to critically debate and research injustices.

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Climate change and decarbonization raise complex justice questions that researchers and policymakers must address. The distributions of greenhouse gas emissions rights and mitigation efforts have dominated justice discourses within scenario research, an integrative element of the IPCC. However, the space of justice considerations is much larger. At present, there is no consistent approach to comprehensively incorporate and examine justice considerations. Here we propose a conceptual framework grounded in philosophical theory for this purpose. We apply this framework to climate mitigation scenarios (...) literature as proof of concept, enabling a more holistic and multidimensional investigation of justice. We identify areas of future research, including new metrics of service provisioning essential for human well-being. [Can be freely read by clicking the ReadCube link below.]. (shrink)

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Mismatch brain responses to unpredicted rare stimuli are suggested to be a neural indicator of prediction error, but this has rarely been studied in the somatosensory modality. Here, we investigated how the brain responds to unpredictable and predictable rare events. Magnetoencephalography responses were measured in adults frequently presented with somatosensory stimuli that were occasionally replaced by two consecutively presented rare stimuli [unpredictable rare stimulus and predictable rare stimulus ; p = 0.1 for each]. The FRE and PR were electrical stimulations (...) administered to either the little finger or the forefinger in a counterbalanced manner between the two conditions. The UR was a simultaneous electrical stimulation to both the forefinger and the little finger. The grand-averaged responses were characterized by two main components: one at 30–100 ms and the other at 130–230 ms latency. Source-level analysis was conducted for the primary somatosensory cortex and the secondary somatosensory cortex. The M55 responses were larger for the UR and PR than for the FRE in both the SI and the SII areas and were larger for the UR than for the PR. For M150, both investigated areas showed increased activity for the UR and the PR compared to the FRE. Interestingly, although the UR was larger in stimulus energy and had a larger prediction error potential than the PR, the M150 responses to these two rare stimuli did not differ in source strength in either the SI or the SII area. The results suggest that M55, but not M150, can possibly be associated with prediction error signals. These findings highlight the need for disentangling prediction error and rareness-related effects in future studies investigating prediction error signals. (shrink)

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Jarmo Pulkkinen, The threat of logical mathematism. A study on the critique of mathematical logic in Germany at the turn of the 20th century. Frankfurt a.M:Peter Lang, 1994. Scandinavian University Studies in the Humanities and Social Sciences; 7). 186 pp. 24 DM. ISBN 3-631-47409-1.

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1- The first period of human life in prehistoric times was known as the period of food gathering economy, as it depended on gathering wild plants and hunting animals, and made simple tools and machines from stones and animal bones that were used in hunting, and used tree leaves and animal skins to make clothes. As for the second period, the Neolithic era, it was known as the period of food production economy when he learned agriculture and domesticated animals. Agriculture (...) was initially described as meeting the need and was cultivated in small areas and in one season. 2- When he learned the life of stability and lived in permanent villages, the oldest of which is the village ofJarmo, many tools were found made of flint, stone vessels, spoons and pottery. In addition, the village contained permanent houses and clay ovens for making bread, fireplaces, basins, stoves and clay dolls. 3- Domesticating animals, especially goats, sheep and pigs, benefiting from their meat, cheese, skins and fat to make oils, and domesticating dogs. 4- The most important crops that he cultivated were wheat and barley, and later in other areas he cultivated lentils, flax and legumes. 5- In the Stone Age, he learned fertilization and artificial irrigation. He cultivated large areas and had a surplus in production, which prompted him to make large-sized stores to store the surplus, noting that the stores had existed since the era of Hassouna, but they were small. He also learned trade and the barter system and the discovery of metals. Specialization in work and division of labor appeared, and other crafts and professions appeared. The pottery wheel, spinning and weaving discs, and seals were invented. 6- Wool and hair of sheep and goats and some plants such as flax were used to make clothes using spinning discs. 7- Many pottery vessels of different sizes and shapes were found, and they contained drawings, decorations, engravings, and colors of great precision, some of which were made by hand and others with a pottery wheel. Tools and machines were made of copper. 8- Moving to the south and the emergence of large cities, carrying out irrigation projects, and the emergence of the first systems of government. 9- A change and development occurred in the human mind, benefiting from the natural environment and the wealth it contains that could serve him as a result of the development of social, cultural and economic life. 10- Plant cultivation and domestication were coupled with animal husbandry and domestication, as both complement each other in terms of benefit. Because of them, other crafts and professions emerged, including the manufacture of tools and machines, pottery and weaving. Trade also flourished as a result of an increase in the surplus and the increase in labor. 11- Learning how to extract oils and methods of obtaining them from plants and animals which was of great importance because it had multiple uses, especially in cooking, and the demand for it increased in trade. 12- Plant and animal wealth played an important role in its prosperity and economic recovery, as it represented the backbone of the economy of Mesopotamia. 13- Our information about animals and plants came from cuneiform texts and seals that show scenes of hunting animals, scenes of grazing sheep, scenes of ears of wheat and plants, and from murals on the walls of palaces, scenes of barns designated for raising animals, scenes of relief and three-dimensional sculptures that show domesticated domesticated animals, and scenes of hunting predatory animals. (shrink)

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