Nanodefects in nanostructures

The notion of nanodefects (topological defects of nanoscale translational order) in nanostructures of various types is introduced. Experimental data reported in the literature are discussed giving direct evidence for the existence of nanodefects in self-assembled periodically ordered nanostructures such as arrays of quantum dots, self-assembled superlattice films of nanoparticles, and arrays of carbon nanotubes. Also, the specific geometric features of perfect and partial cellular dislocations (being a kind of nanodefect) and their role in superplastic deformation in nanocrystalline materials are considered.     

A test of the sensorimotor account of vision and visual perception

Two theories define the relationship between sensory experience and perception of location. The doctrine of specific nerve energies relies on hard-wired, genetically specified relationships between stimulation and perception, modifiable only within limits by adaptation. In a newer sensorimotor account, experience tunes the relationship between stimulation and perception. The perception of pressure phosphenes can differentiate the two theories, because the phosphene appears at a location predicted by physiological optics and in a modality predicted by specific nerve energies. Moving a finger vertically along the outer orbit of the eye while pressing gently on it through the lid during nasally directed gaze results in apparent motion of the phosphene out of phase with the finger, therefore in contradiction to information from motor efference to the finger, tactile sense at the fingertip, eyelid and bulb, joint receptors, and proprioception from muscles driving the finger. A test of the sensorimotor theory giving it every advantage had six observers in darkness moving their fingers along the eye and observing phosphenes for 1 h and 2400 motion cycles; the phosphene always obeyed the doctrine of specific nerve energies, never adapting or changing modality as the sensorimotor theory predicts.     

A phase-field model for deformation twinning

We propose a phase-field model for modeling microstructure evolution during deformation twinning. The order parameters are proportional to the shear strains defined in terms of twin plane orientations and twinning directions. Using a face-centered cubic Al as an example, the deformation energy as a function of shear strain is obtained using first-principle calculations. The gradient energy coefficients are fitted to the twin boundary energies along the twinning planes and to the dislocation core energies along the directions that are perpendicular to the twinning planes. The elastic strain energy of a twinned structure is included using the Khachaturyan's elastic theory. We simulated the twinning process and microstructure evolution under a number of fixed deformations and predicted the twinning plane orientations and microstructures.     

Ordered nanostructures by site-specific heterogeneous nucleation

Highly site-specific heterogeneous nucleation from the vapour phase has been exploited to produce metallic nanostructures on reconstructed ceramic surfaces. The site-specificity arises from the fact that nucleation takes place under highly undersaturated conditions and hence occurs only on specific favourable sites. This approach has been used to produce ordered arrays of nanoparticles, nanorods and nanowires of different metals. The experimental conditions needed to produce different nanostructures are elucidated.     

A novel method for measurement of electronic work function of micro/nanostructure materials using a Kelvin probe system

Work function (WF) can be measured using the Kelvin probe (KP) technique to characterize surface behavior of micro/nanostructures grown on substrates such as metals or semiconductors. However, for such micro/nanostructures, substrates with different WF can strongly affect the measurements if they are exposed directly to face the Kevin probe tip. In this article, a model is proposed to investigate the WF of sparse ZnO nanorods grown on an Si substrate. It is demonstrated that theoretical results from the model are consistent with experimental observations performed using a KP system.     

Primary, secondary, and emotional control across adulthood

Schulz and Heckhausen (1996) have recently formulated a theory of successful aging that centers on perceptions of control as a major theme in the developmental process. They suggest primary control is a universal phenomenon and that people will strive for primary control over secondary control. Secondary control mechanisms, on the other hand, may serve to mediate losses in primary control. This study evaluates the relationship between primary and secondary control among 327 men and women, by administering a general sense of control scale and an emotion control measure with four sub-scales. Consistent with previous research, both age and gender differences were found in primary and secondary control. The results of this study provide support for the theory of emotional selectivity which postulates that as people age they are more able to regulate their emotions, thereby directing energies at increasing secondary control mechanisms (Carstensen, 1986).     

Primary, secondary, and emotional control across adulthood

Schulz and Heckhausen (1996) have recently formulated a theory of successful aging that centers on perceptions of control as a major theme in the developmental process. They suggest primary control is a universal phenomenon and that people will strive for primary control over secondary control. Secondary control mechanisms, on the other hand, may serve to mediate losses in primary control. This study evaluates the relationship between primary and secondary control among 327 men and women, by administering a general sense of control scale and an emotion control measure with four sub-scales. Consistent with previous research, both age and gender differences were found in primary and secondary control. The results of this study provide support for the theory of emotional selectivity which postulates that as people age they are more able to regulate their emotions, thereby directing energies at increasing secondary control mechanisms (Carstensen, 1986).     

Strategy for Dualism

Dualists need to change their argumentative strategies if they wish to make a plausible case for dualism. In particular, dualists should not merely react and respond to physicalist views and arguments; they need to develop their own positive agenda. But neither should they focus their energies on constructing a priori arguments for dualism. Rather, dualists should acknowledge that what supports their view that consciousness exists and is a nonphysical phenomenon is observation, not argumentation. What is needed is a positive account of the nature of consciousness and the indispensable role that it plays in our lives, for it is only by showing the explanatory utility of the nonphysical that dualists can begin to discredit those who would deny its existence. In this paper, I try to give some idea of what such a positive theory of consciousness would look like. In particular, I argue for a theory of consciousness that contains a priori synthetic truths about the ontological nature and causal powers of consciousness.     

Our Growing Understanding of Subtle Energies and Their Function in the Evolving Universe

This article focuses on subtle energies (those energies that fall outside the four regularly recognized energy forces of gravity, electromagnetism, and the strong and weak nuclear forces). Research and insights from the social, physical, and healing sciences are discussed. Key concepts from these disciplines are explored creating a cross-disciplinary analysis of recent research. A case is made for building upon the growing understanding of the influence and importance of the subtle energies in our daily lives as well as the ongoing evolution of our species and planet. The author advocates for increased explorations in the use of these energies for positive social transformation and healing.     

Do new Ethical Issues Arise at Each Stage of Nanotechnological Development?

The literature concerning ethical issues associated with nanotechnologies has become prolific. However, it has been claimed that ethical problems are only at stake with rather sophisticated nanotechnologies such as active nanostructures, integrated nanosystems and heterogeneous molecular nanosystems, whereas more basic nanotechnologies such as passive nanostructures mainly pose technical difficulties. In this paper I argue that fundamental ethical issues are already at stake with this more basic kind of nanotechnologies and that ethics impacts every kind of nanotechnologies, already from the simplest kind of engineered nanoproducts. These ethical issues are mainly associated with the social desirability of nanotechnologies, with the difficulties to define nanotechnologies properly, with the important uncertainties surrounding nanotechnologies, with the threat of ‘nano-divide’, and with nanotechnology as ‘dual-use technology’.     

Effects of absolute mask energy and mask energy range on metacontrast suppression

In an experiment similar to one by Bernstein, Fisicaro, and Fox (1976), subjects were asked to judge the brightness of test stimuli in a metacontrast display. The energies of the test and of the mask varied orthogonally. Various experimental conditions differed with respect to the range of mask energies. Individually, the mask energies were generally weaker than the test energies. The results replicated the main findings of Bernstein et al. (1976) in that judgments of the test were negatively correlated with mask energy at short stimulus onset asynchrony (SOA) but positively correlated at long SOA. These effects were more pronounced when the masks were similar in energy range and level to the tests than when they were wider in energy range and weaker. In general, there was no evidence for the effects of trial-to-trial variation described by Hake, Faust, McIntyre, and Murray     

Planar dissociations and recombination energy of [110] superdislocations in Ni3Al: Generalized Peierls model in combination with ab initioelectron theory

Planar dissociation configurations of the [110] superdislocation in stoichiometric Ni₃Al are investigated by the generalized Peierls model using the {111} γ-surface energies calculated by the ab initio electron theory. The dissociation into four Shockley partials with the formation of an antiphase boundary and two complex stacking fault (CSF) ribbons turned out to be the energetically most favourable configuration. For the edge superdislocation the obtained dissociation widths should be large enough to be resolved in a weakbeam image, whereas for the corresponding configuration of the screw superdislocation the CSF ribbon has a rather small width which may be beyond the limit of the resolution. A twofold dissociation involving a superlattice intrinsic stacking fault is energetically less favourable. The recombination energy of the two Shockley partials in one superpartial is found to be 0.24eV/b.     

Effective Hamiltonian of the two-band Hubbard model: An exact result

An effective Hamiltonian for the two-band Hubbard model was derived by a canonical transformation which was calculated and summed up to infinite order . The transformed Hamiltonian contains terms with strongly renormalized interaction energies. These new interaction energies show sign reversals as a function of the hopping integral in addition to a strong reduction in the charge-transfer gap and a significant increase in the attractive oxygen Hubbard term.     

Via Kundalini: Psychosomatic excursions in transpersonal psychology

Abstract

A model of psychosomatic mysticism (PM) is proposed that reintroduces the body into transpersonal psychology. The argument for PM develops links between transpersonal psychology and neuroimmunology and includes scientific notions of the mind as embodied not just in the brain but more widely throughout the body, as well as the comparative analyses of perspectives on the body in various spiritual traditions. PM is used to examine how transpersonal psychology can integrate the body, thus meeting the goals of the clinician, the standards of the researcher, and the emerging needs of psychosomatic medicine. The core principles of PM are explicated, such as: 1) decentralized consciousness, 2) structural phenomenological correlations between the psyche and the body, 3) in‐depth understanding of energy as intentionality, and 4) the possibility of actualizing cosmic awareness in the individual psyche. Examples of the clinical use of psychospiritual practices of PM show practical applications of these principles. It is concluded that the studies of the embodied consciousness and subtle energies through PM can help to develop both transpersonal theory and applications.     

Stacking fault and dislocation glide on the basal plane of graphite

Generalized stacking-fault energies for the basal plane of graphite are calculated from first principles for slip along two high-symmetry directions. The rhombohedral fault energy compares well with experiment and the anisotropy in behaviour is consistent with observed dislocation network geometry. Utilizing these calculated fault energies within a modified Peierls-Nabarro model, we estimate the barrier for basal dislocation motion based on lattice friction. This is found to be extremely small, from which we conclude that dislocation network interaction and pinning, rather than the Peierls barrier, must determine the practical shear strength of graphite. However, at low dislocation densities or over small crystallite regions, the shear strength should tend to this lower limit. We discuss the relevance of this to the mechanism of lubrication.     

Characteristics,Properties and Ethical Issues of Carbon Nanotubes in Biomedical Applications

The field of nanotechnology and nanoscience is growing rapidly in many areas of research, from electronics to biomedicine to material science. Carbon nanotubes are receiving a lot of attention in the research due to their unique properties and many possible applications. This new material is a good example of how nanotechnology provides us with new opportunities, but at the same time leaves us a lot of unknowns to deal with. In order to deal with the unknowns we need to consider both the science and the ethics of the different applications of this novel material. Nanoethics is the study of the ethical issues in nanotechnology. It is a relatively new field of study and a lot of different methods have been suggested in this area. In this article a method is suggested combining an existing ethical theory with a practical approach in order to do a case study of the ethical considerations of using carbon nanotubes in biomedicine. For the case study to be of practical significance the scientific characteristics and properties of carbon nanotubes are reviewed to give the reader an overview of the research field.     

Effects of irradiation with electrons of different energies on the dark conductivity and the network of hydrogenated amorphous silicon films

The effects of irradiation with electrons having energies in the range 0.7–1.7 MeV on the dark conductivity and the network of hydrogenated amorphous silicon (a-Si:H) thin films have been studied. The dark conductivity measurements show that electron irradiation leads to a degradation in the dark conductivity, with the degradation being greater at lower electron energies. The Raman results suggest that the irradiation induces structural defects in the a-Si:H films, with the lower energy electrons producing more disorder in the amorphous network.     

Galileo's eye: a new vision of the senses in the work of Galileo Galilei

Reflections on the senses, and particularly on vision, permeate the writings of Galileo Galilei, one of the main protagonists of the scientific revolution. This aspect of his work has received scant attention by historians, in spite of its importance for his achievements in astronomy, and also for the significance in the innovative scientific methodology he fostered. Galileo's vision pursued a different path from the main stream of the then contemporary studies in the field; these were concerned with the dioptrics and anatomy of the eye, as elaborated mainly by Johannes Kepler and Christoph Scheiner. Galileo was more concerned with the phenomenology rather than with the mechanisms of the visual process. His general interest in the senses was psychological and philosophical; it reflected the fallacies and limits of the senses and the ways in which scientific knowledge of the world could be gathered from potentially deceptive appearances. Galileo's innovative conception of the relation between the senses and external reality contrasted with the classical tradition dominated by Aristotle; it paved the way for the modern understanding of sensory processing, culminating two centuries later in Johannes Müller's elaboration of the doctrine of specific nerve energies and in Helmholtz's general theory of perception.     

The history of large group phenomena in relation to group analytic psychotherapy: The story of the median group

This paper presents a history of the large group approach in relation to Foulkesian group analytic psychotherapy, including the nature of this approach in relation to Foulkesian principles. Much of the theory reflects Foulkes's attitude, but there are also clear distinctions made, notably a new stance in our thinking about groups as a result of the increase in size (i.e., a membership of about 20), the introduction of the cultural dimension which this increase entails, and the question of what happens after the resolution of Kleinian, oedipal and familial conflicts has been achieved in psychoanalysis and small groups, no-tably what happens once “exile” has been achieved. The approach presented proposes to handle the frustration and hate that these conflicts engender in the form of negative or antilibidinal energies, and their transformation into psychic energy, through dialogue leading from hate to the establishment of koinonia, or impersonal fellowship, and of microcultural influences which promote rather than inhibit communication. Being neither small nor large, a group of about 20 members has become known as a “median” group.     

Apparent movement and metacontrast suppression: A decisional analysis

Three test and three mask energies were varied orthogonally and randomly over trials. The stimulus onset asynchrony (ISOA) separating test and mask was varied between trial blocks within each of two display conditions, apparent movement (two-object) and metacontrast (threeobject). Subjects were required to makebrightness judgments of both test and mask energies by responding “bright,” “medium,” or “dim” with respect to the apparent intensity of each stimulus. The accuracy and the coherence lconsistencyt of test judgments were U-shaped functions of SOA for both apparent movement and metacontrast situations. However, the accuracy and the coherence of mask judgments did not vary with SOA for either apparent movement or metacontrast. It was noted that substantially the same results have been reported previously when subjects were required to makecontour judgments. Hence, it is argued that apparent movement and metacontrast suppression are intimately related.