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Lifecycle assessment (LCA) modeling provides a quantitative statement about resource issues and environmental issues in waste management useful in evaluating alternative management systems and in mapping where major loads and savings take place within existing systems. Chapter 3.1 describes the concepts behind LCA modeling and Chapter 3.2 gives an overview of existing models and shows examples of their application. A recent comprehensive review of publicly available LCA studies (WRAP, 2006) concluded that, on a material basis, LCA modeling in general confirms the validity of the waste hierarchy and shows that recycling is superior to incineration with energy recovery, which again is better than landfilling. Cleary (2010) reviewed 20 waste management scenarios assessed in 11 studies published in the period 2002–2008 and concluded that, due to lack of transparency regarding boundary conditions and exchange with the energy systems, a comparison of results was hampered on a system level. In addition, differences in waste composition may affect the LCA results. This chapter provides results of LCA modeling of 40 waste management scenarios handling the same municipal waste (MSW) and using different combinations of waste recycling, biological treatment, incineration, mechanical–biological treatment and landfilling. The purpose is to compare waste management on a system level and to indentify the steps and treatments within the system contributing the most to the environmental performance of waste management systems. The study focuses on Europe in terms of waste composition and exchange with the energy system. The waste management systems modeled are described with respect to waste composition, waste management technologies, mass flows and energy exchange in the systems. Results are first presented with respect to Global Warming contributions (kg of CO2-eq./t of waste). These data are identical to those presented in Christensen et al. (2009). Finally also results for other

Past research has shown that top-heaviness is a perceptual property that plays a crucial role in triggering newborns’ preference toward faces. The present study examined the contribution of a second configural property, congruency, to newborns’ face preference. Experiments 1 and 2 demonstrated that, when embedded in non-facelike stimuli, congruency induces a preference of the same strength of that induced by facedness. Experiments 3 and 4 demonstrated that the attentional biases toward facedness and congruency produce a cumulative effect on newborns’ visual preferences according to an additive model. These findings were extended by those of Experiment 5, showing that the additive model holds true when congruency is added to top-heaviness in non-facelike stimuli displaying more elements in the upper portion.

An inborn predisposition to attend to biological motion has long been theorized, but had so far been demonstrated only in one animal species (the domestic chicken). In particular, no preference for biological motion was reported for human infants of <3 months of age. We tested 2-day-old babies’ discrimination after familiarization and their spontaneous preferences for biological vs. nonbiological point-light animations. Newborns were shown to be able to discriminate between two different patterns of motion (Exp. 1) and, when first exposed to them, selectively preferred to look at the biological motion display (Exp. 2). This preference was also orientation-dependent: newborns looked longer at upright displays than upside-down displays (Exp. 3). These data support the hypothesis that detection of biological motion is an intrinsic capacity of the visual system, which is presumably part of an evolutionarily ancient and nonspecies-specific system predisposing animals to preferentially attend to other animals.

The present chapter deals with the topic of the ontogeny and development of face processing in the first months of life and is organized into two sections concerning face detection and face recognition. The first section focuses on the mechanisms underlying infants' visual preference for faces. Evidence is reviewed supporting the contention that newborns' face preferences is due to a set of non-specific constraints that stem from the general characteristics of the human visuo-perceptual system, rather than to a representational bias for faces. It is shown that infants' response to faces becomes more and more tuned to the face category over the first 3 months of life, revealing a gradual progressive specialization of the face-processing system. The second section sought to determine the properties of face recognition at birth. In particular, a series of experiments are presented to examine whether the inner facial part is processed and encoded when newborns recognize a face, and what kind of information - featural or configural - newborns' face recognition rely on. Overall, results are consistent with the existence of general constraints present at birth that tune the system to become specialized for faces later during development.

The present study investigated, using the habituation technique, what perceptual cues are used by newborns in the process of recognition of a stranger's face. Evidence showed that newborns are able to discriminate and recognize a face when all the facial features are visible (exp. 1), and when only the inner (exp. 2) or the other features are present (exp. 3).

Existing data indicate that newborns are able to recognize individual faces, but little is known about what perceptual cues drive this ability. The current study showed that either the inner or outer features of the face can act as sufficient cues for newborns' face recognition (Exp.1), but the outer part of the face enjoys an advantage over the inner part (Exp. 2). Inversion of the face stimuli disrupted recognition when only the inner portion of the face was shown, but not when the whole face was fully visible or only the outer features were presented (Exp. 3). The results enhance our picture of what information newborns actually process and encode when they discriminate, learn and recognize faces.

The present study was aimed at investigating whether, because of a differential sensitivity between the upper and the lower visual fields, in a visual preference task newborns would orient more frequently and look longer at patterns with a great number of high-contrast areas in the upper or lower visual field Newborns were presented with three pairs of geometrical stimuli, each composed of a pattern with a greater number of elements in the upper part or a pattern with more elements in the lower part, The results showed a reliable preference for the stimuli that had more elements in the upper than in the lower part. The evidence obtained suggests the possibility that, at birth, the visibility of a stimulus depends not only on its sensory properties, but also on its structural characteristics

The goal of the study was to provide a direct comparison of newborns' ability to process and store, over a 2min delay, the shape of the internal local elements of schematic facelike and non-facelike patterns. Two experiments were carried out using a visual habituation technique with an infant control procedure. The results demonstrate that newborns discriminated between two schematic facelike and non-facelike configurations that differed exclusively for the shape of the internal local elements (Expt 1), and they maintained this discriminative ability even when recognition was tested after a 2min retention interval (Expt 2). The results are consistent with the existence of a general pattern learning mechanism that mediates newborns' ability to acquire information about any pattern, including faces (de Schonen Mancini, 1995; de Schonen, Mancini, Liegeois 1998; Johnson, 1997)

Six experiments are reported that were aimed at demonstrating the presence in newborns of a perceptual dominance of global over local visual information in hierarchical patterns, similar to that observed in adults (D. Navon, 1977, 198 1). The first four experiments showed that, even though both levels of visual information were detectable by the newborn (Experiments 1A and 1B), global cues enjoyed some advantage over local cues (Experiments 2 and 3). Experiments 4A and 4B demonstrated that the global bias was strictly dependent on the low spatial frequency content of the stimuli and vanished after selective removal of low spatial frequencies. The results are interpreted as suggesting parallels between newborns' visual processing and processing later in development

It has been proposed that newborns' preferential orienting to faces is solely controlled by a subcortically mediated orienting mechanism (i.e., Conspec). In contrast preferential-looking tasks show that face preference at birth manifests itself also with measures that index fixation duration. It is possible, however, that orienting and fixation duration are confounded and only orienting matters. The present study used a revised version of the preferential-looking technique, in which the same stimulus (i.e., a facelike or a nonfacelike pattern) was simultaneously presented to both sides of the visual field. Results showed that longer total fixation times on the facelike stimuli resulted from the sum of a greater number of brief fixations, rather than from the sum of a small number of long fixations. These findings support the hypothesis that, for facelike patterns, the duration of infant's fixation on the stimulus is determined by the nature of the pattern that impinges on the periphery of the visual field, more than by the nature of the pattern that is being looked at.

Many studies demonstrated that newborns prefer upright faces over upside-down faces. Based on this evidence, some have suggested that faces represent a special class of stimuli for newborns and there is a qualitative difference between the processes involved in perception of facelike and non-facelike patterns (i.e., structural hypothesis). Others suggest that there is no reason to suppose that faces are different from other patterns, because faces, like any other classes of visual stimuli, are subject to filtering by the properties of the visual system (i.e., sensory hypothesis). The core question that will be adressed in the present paper is whether, to manifest itself, face preference requires the unique structure of the face, represented by the relative spatial location of its internal features, or rather some more general properties that other stimuli may also possess. Evidence will be presented supporting the idea that newborns do not respond to facelike stimuli by "facedness" but, rather, by some general structural characteristics that best satisfy the constraints of the immature visual system.

Four experiments are reported that were aimed at elucidating some of the controversial issues concerning the preference for facelike patterns in newborns. The experiments were devised to contrast the original and the revised versions of the sensory hypothesis and the structural hypothesis as accounts of face preference in newborns, Experiments 1A and 1B supported the structural hypothesis by showing a visual preference for the stimulus for which components were located in the correct arrangement for a human face, Experiment 2 supported the sensory hypothesis by showing a visual preference for stimuli that were designed to have the optimal spatial frequency components for the newborn visual system. Experiment 3 showed that babies directed attention to a facelike pattern also when it was presented simultaneously with a nonfacelike stimulus with optimal spatial frequency for the newborn visual system