Phase Correction Following a Perturbation in Sensorimotor Synchronization Depends on Sensory Information

In models of sensorimotor synchronization, it is generally assumed that phase correction occurs in response to information about sensorimotor asynchrony or relative phase. Without such feedback, a phase perturbation in the motor activity should not be followed by phase correction. Alternatively, internally generated temporal expectations could provide a basis for phase correction in the absence of feedback. To test those hypotheses, the author conducted an experiment in which participants (N = 8) tapped their finger in synchrony with isochronous auditory sequences containing a single shifted event onset, after which there could be a gap of up to 3 missing events. Participants were instructed to not react to the shifted event and to continue tapping regularly during any gap. The shifted event caused an involuntary phase shift of the following tap. The shift was corrected if the sequence continued, but during a gap, the shift persisted without correction. Those results confirm that sensory feedback is necessary for phase correction to occur.     

Reward feedback processing in children and adolescents: Medial frontal theta oscillations

We examined event-related electroencephalography (EEG) oscillations, including event-related spectral perturbations (ERSP) and intertrial coherence (ITC), to compare feedback processing during a chance-based reward vs. non-reward task in groups of 10–12-year-old (n = 42), 13–14-year-old (n = 34) and 15–17-year-olds (n = 32). Because few, if any studies have applied these analytic methods to examine feedback processing in children or adolescents, we used a fine-grained approach that explored one half hertz by 16 ms increments during feedback (no win vs. win events) in the theta (4–8 Hz) frequency band. Complex wavelet frequency decomposition revealed that no win feedback was associated with enhanced theta power and phase coherence. We observed condition and age-based differences for both ERSP and ITC, with stronger effects for ITC. The transition from childhood to early adolescence (13–14 yrs.) was a point of increased differentiation of ITC favoring no win vs. wins feedback and also compared to children or older adolescents, a point of heightened ITC for no win feedback (quadratic effect).     

The trial period and the creation of analytic patients

Just as there are many roads to Rome, the trial period may be considered one of many opening moves in psychotherapy or psychoanalysis. The responsive – and responsible – therapist must be many things to many patients, some of whom know nothing about the psychotherapeutic/analytic process. Freud advocated the trial period to help him take a “sounding” when he knew little about the patient and when the patient knew little about psychoanalysis. R.I.P.? This brief communication laments the apparent demise of this promising procedure and makes an effort at resurrection by describing the hitherto unmapped latent structure of the trial period. Even if there are fewer patients in psychoanalysis today, there may be a number of reasons to recommend a trial period, no matter what we name this period of optimistic uncertainty at the beginning of every treatment. Even if “consultation” is the term de jour, the psychoanalytic psychotherapist cannot escape certain role responsibilities at the beginning of every treatment, which has been made clear in the ethical principles of the American Psychoanalytic Association. What we will learn about the trial period should serve our understanding of what must also occur in the beginning of every psychotherapy or psychoanalysis. Conceptually, I propose that a trial analysis (1) will serve as a discriminative stimulus, signaling, to the patient, the unique nature of the analytic conversation; (2) will permit an in vivo assessment of the patient's suitability for psychoanalysis, and, more importantly, the fit between analyst and patient; (3) will provide anticipatory socialization for the unfamiliar and difficult roles of patient and therapist within the analytic process; (4) will offer true informed consent about the task facing therapist and patient; and (5) will facilitate an opportunity for therapeutic assessment, all of which will help the naive patient acquire the skills and lived experience to become an analytic patient. The trial period is the perfect host for all that must happen – and what we can do– to help naive patients become analytic patients.     

Combined effect of strontium modifier and antimony refiner on texture and growth mode of eutectic phase in an Al-11Si-2Cu-0.8Zn-0.6Fe cast alloy

Results of electron back-scattered diffraction and transmission electron microscopy studies reveal that the orientation of aluminium in the eutectic phase is different from the surrounding aluminium dendrites and that twin spacing of eutectic silicon increased significantly due to the interaction between strontium and antimony. In addition, the formation of ternary Mg₂Sb₂Sr intermetallic compound that precedes the eutectic reaction was proposed to be responsible for interaction.     

Criteria of kinetic suppression of lateral growth of intermediate phases

In many cases, the formation of intermediate phases in solid-state reaction starts from nucleation, proceeds at first by lateral spreading along interface in the form of narrow layer and after that continues slow growth in normal direction. So far, the lateral growth stage was considered as something almost instant. Yet, if the emerging phase is not the first one and the already growing phase layer has high diffusivity, the lateral growth can be also kinetically suppressed due to ‘sucking out’ of atoms from the moving interface into the growing first phase layer. Criteria of such suppression are formulated and examples of real systems are discussed.     

Formation and analysis of amorphous and nanocrystalline phases in Al–Cu–Mg alloy under friction stir processing

Homogeneous amorphous and nanocrystalline phases formed in the nugget zone of a friction stir-processed Al–Cu–Mg alloy have been studied. X-ray diffraction analysis indicated a diffuse scattering peak with characteristics of an amorphous phase existed in the range 15°–29°. Further, TEM analysis proved the existence of an amorphous structure. Friction stir processing provides special physical conditions, such as high temperature, high hydrostatic pressure and large shear stress, which could induce the amorphization of the alloy.     

Phase transformation of Cu precipitate in Fe–Cu alloy studied using self-guided molecular dynamics

The self-guided molecular dynamics (SGMD) method, which can enhance the conformational sampling efficiency in MD simulations, was applied in investigating the phase transformation of Cu precipitate in α-iron that took place during thermal aging. It was shown that the SGMD method can accelerate calculating the bcc to 9R structure transformation of a small precipitate (even 4.0 nm in size), enabling the transformation without introducing any excess vacancies. The size dependence of the transformation also agreed with that seen in previous experimental studies.     

Mechanism of formation of aligned two-phase microstructure in a Fe-0.25wt%C alloy under high magnetic field gradients

The effect of a magnetic force on creating an aligned two-phase microstructure in a Fe-0.25wt%C alloy under magnetic field gradients has been investigated. Through the changes in the heating temperature, both dipolar interactions and magnetic forces work together during the austenite to ferrite transformation. The results showed that the aligned two-phase microstructure is not observed under the influence of the magnetic force alone. The ferrite grains are elongated due to dipole interactions at the early stages of their nucleation and growth and then the magnetic force turns the elongated ferrite grains, whose major axis is not parallel to the direction of magnetic force, to the direction of the field in the presence of magnetic field gradients.     

Nanoindentation measurements on deformation-induced α’-martensite in a metastable austenitic high-alloy CrMnNi steel

The hardness of deformation-induced α’- martensite and parent austenitic matrix in high-alloy CrMnNi steel was investigated by nanoindentation measurements inside scanning electron microscope using picoindenter. After the indentation, the microstructure was investigated by electron backscattered diffraction measurements. The hardness values for α’-martensite are only 24% higher than those of austenite. Thus, the increase in strength during the formation of deformation-induced α’-martensite is rather caused by the small grain size of α’-nuclei resulting in a dynamic Hall–Petch effect than by its “intrinsic” hardness.