Nanoscale spin-wave circuits based on engineered reconfigurable spin-textures

Magnonics is gaining momentum as an emerging technology for information processing. The wave character and Joule heating-free propagation of spin-waves hold promises for highly efficient computing platforms, based on integrated magnonic circuits. The realization of such nanoscale circuitry is crucial, although extremely challenging due to the difficulty of tailoring the nanoscopic magnetic properties with conventional approaches. Here we experimentally realize a nanoscale reconfigurable spin-wave circuitry by using patterned spin-textures. By space and time-resolved scanning transmission X-ray microscopy imaging, we directly visualize the channeling and steering of propagating spin-waves in arbitrarily shaped nanomagnonic waveguides, with no need for external magnetic fields or currents. Furthermore, we demonstrate a prototypic circuit based on two converging nanowaveguides, allowing for the tunable spatial superposition and interference of confined spin-waves modes. This work paves the way to the use of engineered spin-textures as building blocks of spin-wave based computing devices

Emotional dysregulation and callous unemotional traits as possible predictors of short-term response to methylphenidate monotherapy in drug-naïve youth with ADHD

Background: emotional dysregulation (ED) and callous unemotional (CU) traits can be associated with ADHD in youth, influencing its natural history and outcome, but their effect on medication efficacy is unexplored. We examined whether two measures of baseline ED and CU traits, the Child Behavior Checklist-Dysregulation Profile (CBCL-DP) and the Antisocial Process Screening Device (APSD), respectively, were predictors of change of ADHD-Rating Scale (ADHD-RS) after a 4-week methylphenidate (MPH) monotherapy.Methods: 43 patients (37 males, 8–16 years, mean 9.9 ± 2.7 years) were included. Hierarchical linear regression models were used to explore whether CBCL-DP and APSD might predict ADHD-RS score, controlling for baseline severity.Results: saseline CBCL-DP predicted higher post-treatment ADHD-RS scores in total and hyperactivity-impulsivity, but not in inattention subscale. Baseline APSD was not significantly related to ADHD-RS scores at the follow-up.Limitations: small sample size, lack of gender diversity, non-blind design and short period of observation.Conclusion: ED, assessed with that CBCL-DP, might be a negative predictor of change of hyperactive-impulsive symptoms after MPH treatment and should be systematically assessed at baseline

Effects of melatonin in children with attention-deficit/ hyperactivity disorder with sleep disorders after methylphenidate treatment

Purpose: Methylphenidate (MPH), the first-line medication in children with attention-deficit/hyperactivity disorder (ADHD), is associated with increased risk of sleep disorders. Melatonin has both hypnotic and chronobiotic properties that influence circadian rhythm sleep disorders. This study explores the effectiveness of melatonin in children with ADHD who developed sleep problems after starting MPH. Patients and methods: This study, based on a clinical database, included 74 children (69 males, mean age 11.6±2.2 years) naturalistically treated with MPH (mean dosage 33.5±13.5 mg/d). The severity of sleep disorder (sleep onset delay) was recorded at baseline and after a follow-up of at least 4 weeks using a seven-point Likert scale according to the Clinical Global Impression Severity score. Effectiveness of melatonin on sleep (mean dosage 1.85±0.84 mg/d) after 4 weeks was assessed using a seven-point Likert scale according to the Clinical Global Impression Improvement (CGI-I) score, and patients who scored 1 (very much improved) or 2 (much improved) were considered responders. Results: Clinical severity of sleep disorders was 3.41±0.70 at the baseline and 2.13±1.05 after the follow-up (P<0.001). According to the CGI-I score, 45 patients (60.8%) responded to the treatment with melatonin. Gender and age (children younger and older than 12 years) did not affect the response to melatonin on sleep. Patients with or without comorbidities did not differ according to sleep response. Specific comorbidities with disruptive behavior disorders (oppositional defiant disorder or conduct disorder), affective (mood and anxiety) disorders and learning disabilities did not affect the efficacy of melatonin on sleep. Treatment was well tolerated, and no side effects related to melatonin were reported. Conclusion: In children with ADHD with sleep problems after receiving MPH treatment, melatonin may be an effective and safe treatment, irrespective of gender, age and comorbidities

Callous–Unemotional Traits and Intelligence in Children with Externalizing Behavioral Problems

Research on the association between callous–unemotional (CU) traits and intelligence yielded contradictory results. Moreover, several previous studies focused on global intelligence scores or verbal vs. nonverbal/performance abilities usually evaluated with short/abbreviated instruments. The current study builds on these previous works and explores the link between CU traits and intelligence using the full version of the Wechsler Intelligence Scale for Children—4th Edition (WISC-IV), which provides four different verbal and nonverbal abilities scores. This guarantees a more detailed evaluation of children’s intelligence and its relation to CU traits. The sample included children (N = 149; age 6–14 years old) with severe behavioral problems. Clinicians administered the WISC-IV, and parents completed questionnaires evaluating the child’s externalizing problems and CU traits. Findings showed that CU traits were associated with lower verbal comprehension scores after also controlling for gender, age, externalizing problems, and the other WISC-IV indexes. In addition, CU traits and externalizing problems did not interact in predicting the WISC-IV indexes, and there were no significant differences in the WISC-IV indexes between children with CU traits and high vs. low externalizing problems. The current study suggests the relevance of assessing and addressing verbal abilities in children with behavioral problems and CU traits

Treatment with Methylphenidate Improves Affective but Not Cognitive Empathy in Youths with Attention-Deficit/Hyperactivity Disorder

Background: Beside the core symptoms, patients with attention-deficit/hyperactivity disorder (ADHD) frequently show relevant difficulty in developing relationships with peers. Although ADHD symptoms may account for social impairment, deficits in cognitive and/or affective empathy have also been involved. Our aim was to investigate the effect of methylphenidate (MPH) treatment on affective and cognitive empathy. Methods: Sixty-one drug-naïve youths with ADHD (age range 6 to 17 years, mean 10.3 ± 2.8 years, 51 males) naturalistically treated with MPH monotherapy were followed up for 6 months for ADHD symptoms and empathy, measured with the Basic Empathy Scale. Results: After being treated with MPH, the patients showed a significant improvement in affective and cognitive empathy scores. Linear regression models showed that changes in inattention symptoms predicted changes in affective but not in cognitive empathy, while changes in the hyperactivity/impulsivity symptoms did not predict changes in affective or cognitive empathy. Conclusions: Our study provides a further contribution for a better understanding of the possible effects of the MPH on youth’s characteristics

Internet Gaming Disorder in Children and Adolescents with Attention Deficit Hyperactivity Disorder

Although Attention Deficit Hyperactivity Disorder (ADHD) has been related to an increased risk for behavioral addictions, the relationship between ADHD and Internet Gaming Disorder (IGD) is still debated. The aim of this study is to address this topic by exploring the prevalence of IGD in a consecutive sample of ADHD youth, compared to a normal control group, and by assessing selected psychopathological and cognitive features in ADHD patients with and without IGD. One hundred and eight patients with ADHD (mean age 11.7 ± 2.6 years, 96 males) and 147 normal controls (NC) (mean age 13.9 ± 3.0 years, 114 males) were included in the study and received structured measures for IGD. In the ADHD group, 44% of the sample were above the IGD cut-off, compared to 9.5% in the NC group. ADHD patients with IGD presented with greater severity and impairment, more severe ADHD symptomatology, more internalizing symptoms, particularly withdrawal/depression and socialization problems, and more prominence of addiction and evasion dimensions. A binary logistic regression showed that the degree of inattention presented a greater weight in determining IGD. These findings may be helpful for identifying, among ADHD patients, those at higher risk for developing a superimposed IGD