Optimization of a fiber Fabry-Perot resonator for low-threshold modulation instability Kerr frequency combs.

We report a theoretical and experimental investigation of fiber Fabry-Perot cavities aimed at enhancing Kerr frequency comb generation. The modulation instability (MI) power threshold is derived from the linear stability analysis of a generalized Lugiato-Lefever equation. By combining this analysis with the concepts of power enhancement factor (PEF) and optimal coupling, we predict the ideal manufacturing parameters of fiber Fabry-Perot (FFP) cavities for the MI Kerr frequency comb generation. Our findings reveal a distinction between the optimal coupling for modulation instability and that of the cold cavity. Consequently, mirror reflectivity must be adjusted to suit the specific application. We verified the predictions of our theory by measuring the MI power threshold as a function of detuning for three different cavities.

Low phase noise self-injection-locked diode laser with a high-Q fiber resonator: model and experiment: publisher's note.

This publisher's note contains a correction to Opt. Lett.49, 1933 (2024)10.1364/OL.514778.

Low phase noise self-injection-locked diode laser with a high-Q fiber resonator: model and experiment.

Low phase noise and narrow linewidth lasers are achieved by implementing self-injection locking of a DFB laser on two distinct fiber Fabry-Perot resonators. More than 45 dB improvement of the laser phase or frequency noise is observed when the laser is locked. In both cases, a frequency noise floor below 1 Hz2/Hz is measured. The integrated linewidth of the best of the two lasers is computed to be in the range of 400 Hz and appears to be dominated by vibration noise close to the carrier. The results are then compared with a model based on the retro-injected power and the Q factors ratio between the DFB laser and the resonator. This straightforward model facilitates the extraction of the theoretical performance of these sources close to the carrier, a characteristic still hidden by vibration noise.

Evaluation of a medically coordinated care program in the management of autism.

Autism spectrum disorders (ASD) are neurodevelopmental disorders of varying intensity and disability. The reference health strategy in France for the care of young children with autism is day care hospital (DCH). As the number of places in DCH is insufficient, medically coordinated care programs by the mental health consultation centers (MHCC) are being developed in response. OBJECTIVES: Our objective is to evaluate the effectiveness of a medically coordinated care program in a MHCC versus the care in DCH of child psychiatry. METHODS: Non-inferiority retrospective study comparing the evolution after one year of care of 20 ASD children divided into two groups DCH and MHCC. In the DCH ASD group, the child is taken care of two half-days a week in a day hospital with individual educational care. In the MHCC ASD group, the child benefits from a medically coordinated care program. The medical care is reinforced by more frequent and longer consultations with guidance offered to parents. In both groups, the child receives speech therapy and psychomotor therapy in private practice at the same rate. Comparison is made using a composite criterion associating CARS-2 and VABS-II. Non-inferiority of the medically coordinated care program in autism in reference to DCH was tested on the difference between the changes (DCH group variation - MHCC group variation) with a non-inferiority threshold of 10% of the initial value of each score. RESULTS: We observed a reduction in autism severity at the CARS-2 and a moderate improvement in socio-adaptive behavior at the VABS-II in both groups. This trend was even more pronounced in the MHCC group than in the DCH group, but only the greater reduction in CARS-2 severity in the MHCC was statistically significant. CONCLUSIONS: As it is necessary to integrate the two scales into the composite criterion, it is not possible to retain the non-inferiority of the MHCC with care program. However, both those children followed in DCH and those in the MHCC care program progress. This shows the relevance of the care offered at the MHCC for children suffering from ASD, in the context of a growing lack of space in DCH. The continuation of this research work through multicenter studies with larger numbers could demonstrate the non-inferiority of coordinated care programs in the MHCC versus DCH. It would also allow subgroups to be set up, taking into account the initial characteristics of the children in order to have more precise indications concerning the relevance of each treatment.

[Oral language development in maltreated and foster children]. / Le développement du langage oral chez les enfants maltraités et placés.

Language disorders, which are still very poorly detected, are often present in abused children. While the consequences are well known and long-lasting, little is known about the development and specific characteristics of these children, depending on where they were placed, the type of abuse they suffered and the age at which they were placed. This finding led to a review of the literature aimed at better defining the state of knowledge on the subject, for the benefit of better detection and treatment.

Impact of pump pulse duration on modulation instability Kerr frequency combs in fiber Fabry-Pérot resonators.

We report an experimental investigation on the impact of the pump pulse duration on the modulation instability process in fiber Fabry-Pérot resonators. We demonstrate that cross-phase modulation between the forward and the backward waves alters significantly the modulation instability process. By varying the pump pulse duration, we show the modification of the modulation instability threshold and frequency. These experimental observations are in excellent agreement with theoretical predictions.

Observation of modulation instability Kerr frequency combs in a fiber Fabry-Pérot resonator.

We report the experimental observation of a modulation instability induced Kerr frequency comb in an all fiber Fabry-Pérot resonator. We fully characterized, in intensity and phase, the frequency comb using a commercial 10 MHz resolution heterodyne detection system to reveal more than 125 comb teeth within each of the modulation instability sidelobes. Moreover, we were able to reveal the fine temporal structure in phase and intensity of the output Turing patterns. The experimental results are generally in good agreement with numerical simulations.

Early-onset schizophrenia: studying the links between cognitive and clinical dimensions.

BACKGROUND: Early-onset schizophrenia (EOS), a rare and severe chronic psychiatric condition, is defined by an onset of schizophrenia symptoms before the age of 18. Core symptoms also include cognitive impairments. However, little is known about links between psychiatric symptoms of EOS and cognitive abilities. OBJECTIVE: To explore the clinical and neurocognitive profiles of EOS patients and their links. METHOD: EOS patients have been phenotyped using standardised psychiatric assessments for DSM-5 diagnoses (K-SADS-PL) and for symptoms (PANSS and SANS), together with neurocognitive evaluations. RESULTS: The EOS sample (n = 27, 12.4 +/-3.2 years) presented hallucinations (83%), negative symptoms (70%) and delusion (59%). 81% of patients presented comorbidities such as anxiety disorders (33%), autism spectrum disorder (26%) and attention-deficit hyperactivity disorder (26%). Patients presented borderline intellectual deficiency (total IQ = 72.5 +/-4.7), with low performances in working memory subtest. We highlight a positive correlation between the IQ and intensity of positive symptoms (PANSS) and between the IQ and a first treatment being administered at an older age. We also highlight a negative correlation between the IQ and attention items of SANS. CONCLUSION: Cognitive skills are correlated with symptom intensity in EOS patients. An older age of onset seems to be a protective factor for cognitive development.

[Child psychiatry in pediatric intensive care unit]. / Pédopsychiatrie en unité de soins intensifs pédiatriques.

A study was conducted in the pediatric intensive care and resuscitation unit of the Nice pediatric hospitals, University Hospital Center Lenval (06) from January to March 2015. Its objective was to describe the events and child psychiatric interventions experienced by young patients. Of the 181 individuals managed during the research, 63 met the inclusion criteria.

A novel microduplication in INPP5A segregates with schizophrenia spectrum disorder in the family of a patient with both childhood onset schizophrenia and autism spectrum disorder.

Childhood-Onset Schizophrenia (COS) is a very rare and severe psychiatric disorder defined by adult schizophrenia symptoms occurring before the age of 13. We report a microduplication in the 10q26.3 region including part of the Inositol Polyphosphate-5-Phosphatase A (INPP5A) gene that segregates with Schizophrenia Spectrum Disorders (SSDs) in the family of a female patient affected by both COS and Autism Spectrum Disorder (ASD). Phenotyping and genotyping (including CGH-array) were performed for mother, healthy sister, and affected child according to the GenAuDiss protocol (NCT02565524). The duplication size is 324 kb and is present in a patient with COS and in her mother with SSD, but not in the patient's healthy sister. INPP5A encodes a membrane-associated 43 kDa type I inositol 1,4,5-trisphosphate (InsP3) 5-phosphatase. This protein is found both in mouse and human brains and we found that its Drosophila homologue 5PtaseI is specifically expressed in the central nervous system. Hydrolyzed products from InsP3 5-phosphatases mobilize intracellular calcium, which is relevant for dendritic spine morphogenesis in neurons and altered in both schizophrenia and ASD. These may constitute arguments in favor of this gene alteration in the pathophysiology of COS.

[The psychologist in paediatric intensive care, liaison and separation]. / Le psychologue en réanimation pédiatrique, liaison et séparation.

The relationship between the interventions of liaison psychiatry and those of general medicine is essential. The psychologist, notably, plays an important role in a paediatric intensive care unit. A double temporality, somatic and psychological, is to be taken into account in order to hear, beyond the individual, what the subjet has to say.

Relationship between social cognition and emotional markers and acoustic-verbal hallucination in youth with post-traumatic stress disorder: Protocol for a prospective, 2-year, longitudinal case-control study.

INTRODUCTION: Auditory-verbal hallucinatory experiences (AVH) have a 12% prevalence in the general pediatric population. Literature reports a higher risk of developing AVH in post-traumatic stress disorder (PTSD). The persistence of AVHs during adolescence represents a risk of evolution into psychotic disorders. Social cognition and emotional markers could be considered prodromes markers of this evolution. The objectives of this prospective observational study are to observe social cognition and emotional markers correlation with the presence and persistence of AVH over two years and with the evolution of PTSD and psychotic diagnosis. METHODS AND ANALYSIS: This prospective case-control study, longitudinal over two years (with an interim reassessment at six months and one year), will include 40 participants aged 8 to 16 years old with a diagnosis of PTSD and without a diagnosis of psychosis according to the criteria of DSM-5 (K-SADS-PL). Subjects included are divided into two groups with AVH and without AVH matched by gender, age and diagnosis. The primary outcome measure will be the correlation between social cognition and emotional makers and the presence of AVH in the PTSD pediatric population without psychotic disorders. The social cognition marker is assessed with the NEPSY II test. The emotional marker is assessed with the Differential Emotion Scale IV and the Revised Beliefs About Voices Questionnaire. The secondary outcome measures are the correlation of these markers with the persistence of AVH and the evolution of the patient's initial diagnosis two years later. DISCUSSION: The originality of our protocol is to explore the potential progression to psychosis from PTSD by cognitive biases. This study supports the hypothesis of connections between PTSD and AVH through sensory, emotional and cognitive biases. It proposes a continuum model from PTSD to psychotic disorder due to impaired perception like AVH. TRIAL REGISTRATION: Clinical trial registration: ClinicalTrials.gov Identifier: NCT03356028.

Somatic and Posttraumatic Stress Symptoms in Children and Adolescents in France.

Importance: Somatic symptoms are a major concern among the pediatric population because of frequency and burden. The association between adverse childhood experiences and somatic symptoms in adults is well established but less is known concerning somatic symptoms in young people. Objective: To explore the frequency and intensity of somatic symptoms in children and adolescents exposed to traumatic events. Design, Setting, and Participants: This cross-sectional study was conducted from January 1 to December 31, 2021, at the Nice Pediatric Psychotrauma Referral Center in Nice, France. Participants included pediatric outpatients, aged 7 to 17 years, who were referred to the center. Statistical analysis was performed in January 2022. Exposure: All participants experienced at least 1 traumatic event during life. Main Outcome and Measure: Somatic and posttraumatic stress symptoms were assessed using the Patient Health Questionnaire-13 (PHQ-13) and Child PTSD Checklist (CPC). Posttraumatic stress disorder (PTSD) and non-PTSD groups were defined based on CPC symptoms severity score. In the hypothesized association between somatic symptoms and posttraumatic stress symptoms (PTSS), PTSD and non-PTSD groups were compared, correlations between PTSS and severity of CPC were analyzed, and a regression model was performed. Results: There were 363 participants included (mean [SD] age, 13.58 [0.25] years; 174 [47.9%] female, 189 [52.1%] male). Compared with the non-PTSD group, the PTSD group presented with a higher mean (SD) number of somatic symptoms (7.0 [2.5] vs 4.0 [2.5] symptoms; t360 = 11.7; P < .001), and higher mean (SD) intensity (10.4 [4.6] vs 4.8 [3.7] points; t360 = 12.6; P < .001). Most of the explored somatic symptoms positively correlated with the intensity of PTSS and their functional alterations (eg, PTSS intensity correlated with stomach pain symptoms [r = .30; P < .001]; and with headaches symptoms [r = .44; P < .001]). In the regression model, the combination of migraines, palpitation, nausea, tiredness, and sleep disorders explained 6.5% of the variance in the PTSD group. (F1,341 = 22.651; P < .001). Conclusions and Relevance: In this cross-sectional study, somatic symptoms were positively correlated with PTSS both in frequency and intensity among youths. These results suggest that the systematic screening for somatic symptoms in youths with traumatic exposure should be a routine evaluation procedure.

Psychiatric outcomes in outpatients affected by long COVID: A link between mental health and persistence of olfactory complaint.

BACKGROUND: Anosmia was one of the main symptoms of coronavirus disease 2019 (COVID-19). A psychiatric history (i.e., depression) may be an independent contributor to the risk of COVID-19 diagnosis, and COVID-19 survivors appear to have an increased risk of neuropsychiatric sequelae (bidirectional association). AIM: To compare the rate of psychiatric disorder among post-COVID patients without anosmia vs patients with persistent olfactory complaints. METHODS: We conducted a prospective case control study from March 2020 to May 2021. Patients recruited at the ENT department of Nice University Hospital had a subjective olfactory complaint (visual analogue scale) for over 6 wk and a molecular or CT-proven severe acute respiratory syndrome coronavirus 2 diagnosis confirmed by serology. Post-COVID patients without persistent olfactory disorders were recruited at the university hospital infectiology department. Psychiatric medical histories were collected by a psychiatrist during the assessments. RESULTS: Thirty-four patients with post-COVID-19 olfactory complaints were included in the first group of the study. Fifty percent of the patients were female (n = 17). The group's mean age was 40.5 ± 12.9 years. The control group included 32 participants, of which 34.4% were female (n = 11), and had a mean age of 61.2 ± 12.2 years. The rate of psychiatric disorder among post-COVID patients with olfactory complaints was significatively higher (41.7%) than among patients without (18.8%) (χ2 = 5.9, P = 0.015). CONCLUSION: The presence of a psychiatric history may constitute a potential risk factor for the development of long COVID due to persistent anosmia. It therefore seems important to establish reinforced health monitoring after a COVID 19 infection in at-risk patients. Further prospective, translational, and collaborative studies are needed to extrapolate these results to the general population.

Developmental Profile of Children with Autism Spectrum Disorder Versus Social Communication Disorder: A Pilot Study.

BACKGROUND: Social Communication Disorder (SCD), introduced in the DSM-5, is distinguished from Autism Spectrum Disorder (ASD) by the absence of restricted and repetitive behaviors or interests (RRBIs). AIM: To compare the adaptive, sensory, communication, and cognitive profiles of children with ASD and SCD. METHODS: The assessments of nine children with SCD and ten with ASD were compared with either Fisher's Exact Test or the Mann-Whitney Test. Assessments included the Vineland Adaptive Behavior Scales, the Autism Diagnostic Observation Schedule (ADOS), the Short Sensory Profile, Bishop's Children's Communication Checklist, a pragmatics evaluation, and the Wechsler Intelligence Scale for Children IV. RESULTS: The total ADOS score and the second subtotal "Restricted and Repetitive Behaviors" were significantly higher (p = 0.022) in the ASD group than in the SCD group. The Vineland standard score for the "Socialization" domain was significantly lower (p = 0.037) in the ASD group (mean: 51 +/- 19) than in the SCD group (mean: 80 +/- 28). The working memory index score was also significantly lower (p = 0.013) in the ASD group compared to the SCD group. CONCLUSIONS: While ASD and SCD share similarities in communication and pragmatic difficulties, some distinctions have been identified, e.g. in executive functioning and the impact on socialization, which may be linked to the absence of RRBIs in SCD. These findings highlight the challenges posed by this nosographic separation during diagnostic evaluations due to the scarcity of discriminative tools.

Impact of the 7/14/2016 Nice terrorist attack on pediatric emergency department visits thanks to syndromic surveillance: a descriptive study.

Objective: Study the impact of 14th July 2016 Nice terrorist attack on Pediatric Emergency Department (PED) visits by youth under 18 years of age. Methods: PED visits diagnoses (ICD10) were clustered and analyzed based on retrospective data from the syndromic surveillance system of the Children's university hospital of Nice (Southern France). The studied period ranges from 2013 to 2019, i.e., 3 years before and after the terrorist attack of 14th July 2016. Results: Among 416,191 PED visits, the number of visits for stress in 4-17 years old appeared to increase in the 3 years after the attack compared to the 3 years before, particularly in September 2016 (acute effect) with 11 visits compared to an average of 2.3 visits per month from September 2013 to 2016 (p = 0.001827). In September 2017, we noticed 21 visits compared to an average of 4.8 visits per month during the following period (2013-2019). In 2017, PED visits for stress among 4-17 year olds were higher in comparison to the other years of the study: 107 visits compared to an annual average of 57. Conclusion: To our knowledge, this is the first study of the use of the pediatric care system before and after a terrorist attack involving syndromic surveillance. This suggests acute and long-term effects of the terrorist attack on PED use by youth for mental health issues. Further studies of the pediatric care system involving syndromic surveillance are needed in the context of mass violent events, such as terrorist attacks.

Study protocol: how does parental stress measured by clinical scales and voice acoustic stress markers predict children's response to PTSD trauma-focused therapies?

INTRODUCTION: Post-traumatic stress disorder (PTSD) symptoms in youth are influenced by parental anxiety and stress. When parents have high levels of stress or have developed PTSD themselves, children tend to show more anxiety symptoms. Parental stress can affect the severity of children's PTSD and lower the success of recovery. However, the influence of parental stress on the effectiveness of trauma-focused therapies (eye movement desensitisation and reprocessing and cognitive behavioural therapy) has not yet been investigated to our knowledge. Hence, we will measure parental stress (using both validated scales and vocal acoustic markers) and investigate how it influences children's PTSD recovery. METHOD AND ANALYSIS: Sixty children between the ages of 7 and 15 years who experienced type 1 trauma will be recruited at the Nice Pediatric Psychotrauma Center in France. We plan to measure stress using two different approaches. We will ask parents to answer validated scales of stress and mood in general. Stress will also be measured using vocal acoustic markers. Parents will be recorded while narrating their child's trauma and during the narrative of a positive and neutral recall of events. Child participants will have to complete anxiety, PTSD and depression scales before the beginning of the trauma-focused therapy and after 3 months of treatment.Linear mixed effects models and differential statistics, such as significance testing corrected for multiple testing, will be used to determine the validity of speech features for the proposed hypotheses. Repeated measures analysis of variance will be performed on the clinical scales scores according to parental stress. Correlations will be performed between clinical scales of parents and children according to time of assessment. ETHICS AND DISSEMINATION: This study was approved by the Committee for the Protection of Individuals of the University of Nice Sophia Antipolis (CERNI) on 21 February 2022, under the number CER2022-015.All participants will be informed that this is an observational study and their consent taken prior to the experiment. Participants will be informed that they can withdraw from the study at any time and that it would not affect the care provided. TRIAL REGISTRATION NUMBER: CER AVIS n° 2022-015.