Observation of the Borromean Three-Body Förster Resonances for Three Interacting Rb Rydberg Atoms.

Three-body Förster resonances at long-range interactions of Rydberg atoms were first predicted and observed in Cs Rydberg atoms by Faoro et al. [Nat. Commun. 6, 8173 (2015)NCAOBW2041-172310.1038/ncomms9173]. In these resonances, one of the atoms carries away an energy excess preventing the two-body resonance, leading thus to a Borromean type of Förster energy transfer. But they were in fact observed as the average signal for the large number of atoms N≫1. In this Letter, we report on the first experimental observation of the three-body Förster resonances 3×nP_{3/2}(|M|)→nS_{1/2}+(n+1)S_{1/2}+nP_{3/2}(|M^{*}|) in a few Rb Rydberg atoms with n=36, 37. We have found here clear evidence that there is no signature of the three-body Förster resonance for exactly two interacting Rydberg atoms, while it is present for N=3-5 atoms. This demonstrates the assumption that three-body resonances can generalize to any Rydberg atom. As such resonance represents an effective three-body operator, it can be used to directly control the three-body interactions in quantum simulations and quantum information processing with Rydberg atoms.

Full counting statistics and phase diagram of a dissipative Rydberg gas.

Ultracold gases excited to strongly interacting Rydberg states are a promising system for quantum simulations of many-body systems. For off-resonant excitation of such systems in the dissipative regime, highly correlated many-body states exhibiting, among other characteristics, intermittency and multimodal counting distributions are expected to be created. Here we report on the realization of a dissipative gas of rubidium Rydberg atoms and on the measurement of its full counting statistics and phase diagram for both resonant and off-resonant excitation. We find strongly bimodal counting distributions in the off-resonant regime that are compatible with intermittency due to the coexistence of dynamical phases. Our results pave the way towards detailed studies of many-body effects in Rydberg gases.

Unravelling the clinical heterogeneity of undefined recurrent fever over time in the European registries on Autoinflammation.

BACKGROUND: Systemic autoinflammatory disorders (SAIDs) represent a growing spectrum of diseases characterized by dysregulation of the innate immune system. The most common pediatric autoinflammatory fever syndrome, Periodic Fever, Aphthous Stomatitis, Pharyngitis, Adenitis (PFAPA), has well defined clinical diagnostic criteria, but there is a subset of patients who do not meet these criteria and are classified as undefined autoinflammatory diseases (uAID). This project, endorsed by PRES, supported by the EMERGE fellowship program, aimed to analyze the evolution of symptoms in recurrent fevers without molecular diagnosis in the context of undifferentiated AIDs, focusing on PFAPA and syndrome of undifferentiated recurrent fever (SURF), using data from European AID registries. METHODS: Data of patients with PFAPA, SURF and uSAID were collected from 3 registries including detailed epidemiological, demographic and clinical data, results of the genetic testing and additional laboratory investigations with retrospective application of the modified Marshall and PRINTO/Eurofever classification criteria on the cohort of PFAPA patients and preliminary SURF criteria on uSAID/SURF patients. RESULTS: Clinical presentation of PFAPA is variable and some patients did not fit the conventional PFAPA criteria and exhibit different symptoms. Some patients did not meet the criteria for either PFAPA or SURF, highlighting the heterogeneity within these groups. The study also explored potential overlaps between PFAPA and SURF/uAID, revealing that some patients exhibited symptoms characteristic of both conditions, emphasizing the need for more precise classification criteria. CONCLUSIONS: Patients with recurrent fevers without molecular diagnoses represent a clinically heterogeneous group. Improved classification criteria are needed for both PFAPA and SURF/uAID to accurately identify and manage these patients, ultimately improving clinical outcomes.

Fusobacterium invasive infections in children: a retrospective study in two French tertiary care centres.

The purpose of this investigation was to describe the clinical and biological characteristics and evolution of invasive Fusobacterium infections in children admitted to two French paediatric tertiary care centres. Children who were admitted from 1998 to 2009 to two tertiary care centres for invasive Fusobacterium infection were included in a retrospective study. Thirty-one children with a median age of 5.7 years (interquartile range, IQR [2.3; 9.3]) were included. Nine children had an underlying condition, most commonly sickle cell disease (n = 3) or immunodeficiency (n = 3). Two children had skin effraction prior to the infection. The major sites of infection were the head and neck (n = 14) and abdomen (n = 10). Three children suffered from atypical Lemierre's syndrome. More than half of the children had a bacterial co-infection (58 %). Six children were hospitalised in an intensive care unit, and 67 % of them had a chronic underlying disease. None of the children died. Six children with negative cultures had Fusobacterium identified through 16S RNA-PCR. Fusobacterium is responsible for severe infection in children. Microbiological diagnosis might be improved by the wider use of molecular detection.

Rovibrational cooling of molecules by optical pumping.

We demonstrate rotational and vibrational cooling of cesium dimers by optical pumping techniques. We use two laser sources exciting all the populated rovibrational states, except a target state that thus behaves like a dark state where molecules pile up thanks to absorption-spontaneous emission cycles. We are able to accumulate photoassociated cold Cs(2) molecules in their absolute ground state (v = 0, J = 0) with up to 40% efficiency. Given its simplicity, the method could be extended to other molecules and molecular beams. It also opens up general perspectives in laser cooling the external degrees of freedom of molecules.

Observation of a resonant four-body interaction in cold cesium Rydberg atoms.

Cold Rydberg atoms subject to long-range dipole-dipole interactions represent a particularly interesting system for exploring few-body interactions and probing the transition from 2-body physics to the many-body regime. In this work we report the direct observation of a resonant 4-body Rydberg interaction. We exploit the occurrence of an accidental quasicoincidence of a 2-body and a 4-body resonant Stark-tuned Förster process in cesium to observe a resonant energy transfer requiring the simultaneous interaction of at least four neighboring atoms. These results are relevant for the implementation of quantum gates with Rydberg atoms and for further studies of many-body physics.

Deeply bound cold caesium molecules formed after 0(-)(g) resonant coupling.

Translationally cold caesium molecules are created by photoassociation below the 6s + 6p(1/2) excited state and selectively detected by resonance enhanced two photon ionization (RE2PI). A series of excited vibrational levels belonging to the 0(-)(g) symmetry is identified. The regular progression of the vibrational spacings and of the rotational constants of the 0(-)(g) (6s + 6p(1/2)) levels is strongly altered in two energy domains. These deviations are interpreted in terms of resonant coupling with deeply bound energy levels of two upper 0(-)(g) states dissociating into the 6s + 6p(3/2) and 6s + 5d(3/2) asymptotes. A theoretical model is proposed to explain the coupling and a quantum defect analysis of the perturbed level position is performed. Moreover, the resonant coupling changes dramatically the spontaneous decay products of the photoexcited molecules, strongly enhancing the decay into deeply bound levels of the a(3)Σ(+)(u) triplet state and of the X(1)Σ(+)(g) ground state. These results may be relevant when conceiving population transferring schemes in cold molecule systems.

[Transition from pediatric to adult care: Recommendations of the French network for autoimmune and autoinflammatory diseases (FAI2R)]. / La transition de la pédiatrie à l'âge adulte : recommandations de prise en charge de la filière des maladies auto-immunes et auto-inflammatoires rares FAI2R.

Autoimmune and autoinflammatory diseases (AIDs) are a heterogeneous group of diseases. They can occur in childhood and account for significant morbidity and mortality. Transitioning from pediatric to adult healthcare can be difficult for patients and their families. It can interfere with patient follow-up and management, and eventually lead to complications. Although recommendations exist for the successful transition of patients with chronic diseases, few are specifically adapted to children and adults with AIDs (Suris et al., 2015-Solau-Gervais, 2012). The French working group on transition of the rare autoimmune and autoinflammatory diseases presents its reflections and recommendations for a successful transition. Preparation for transition should start early. Its goals are to empower adolescents by providing them with the knowledge to manage their own care, respond appropriately to changes in their condition, and evolve within the adult healthcare system. This requires the active participation of the patient, his or her family, as well as the pediatric and adult medical teams. The transition process involves multidisciplinary care and dedicated therapeutic education programs. Finally, the identification of medical specialists by region, trained in rare AIDs and accompanied by expert patients, may improve the management of patients with rare AIDs from adolescence to adulthood.

Management of febrile infants aged 1 month and less than 3 months in a French university hospital: Clinical practice evaluation.

BACKGROUND: Management of febrile infants is challenging due to the increased risk of serious bacterial infections and it varies among physicians and hospitals. The goals of this study were to describe and compare the management of febrile infants aged 1-2 months in a hospital in 2011 and 2016. METHODS: We conducted a retrospective study in the Bordeaux Pellegrin University Hospital, France, in 2011 and 2016. All infants aged 1-2 months with diagnosis codes referring to fever were included. Data on infant characteristics, fever episodes, clinical symptoms, and management were collected from medical charts. Univariate analyses and multivariate logistic models were used. RESULTS: A total of 530 infants were included; 89.2% had blood testing and 81.1% urine testing; 79.6% of the infants were hospitalized, three of them in the pediatric intensive care unit. The median hospitalization duration was 3 days. In the sample investigated, 59.8% of the infants received antibiotic therapy and 128 (24.1%) had bacterial infections with no difference between 2011 and 2016. The main bacterial infection was pyelonephritis (86.7%). Urethral catheterization was implemented in 2016, whereas a urine bag was utilized for 174 out of 177 infants in 2011. The percentage of contaminated urine cultures was higher in 2011 (35.9%) than in 2016 (19.6%, P<0.001). The hospitalization rate was higher in 2016. CONCLUSIONS: Management of febrile infants changed between 2011 and 2016. The hospitalization rate and antibiotic therapy use remained high regarding the rate of bacterial infection. Use of urethral catheterization decreased the level of contamination.

[Cataract surgery in children with non-infectious uveitis: Review of current practices in France]. / Chirurgie de la cataracte uvéitique non infectieuse de l'enfant : bilan des pratiques actuelles en France.

PURPOSE: To evaluate the medical-surgical management of cataract surgery in children with chronic uveitis in various French pediatric ophthalmology centers. MATERIALS AND METHODS: Two-part study: first, a descriptive observational segment on the evaluation of French practices. A questionnaire was sent to the various pediatric ophthalmologists in France. A second retrospective chart review, including children with non-infectious chronic uveitis who had cataract surgery in the pediatric ophthalmology department of Bordeaux University Hospital from 2008 to 2017. RESULTS: Twenty-one ophthalmologists responded to the questionnaire. Only 23.8% systematically initiated immunosuppressive drugs (aside from corticosteroids) before surgery. A total of 88.2% prescribed oral corticosteroid treatment preoperatively. Eleven surgeons administered intravenous corticosteroid boluses during the surgery, and primary lens implantation is the most common method used in 95.2%. A total of 76.2% initiated oral steroid therapy after surgery. Postoperatively, all surgeons started local therapy with high-dose corticosteroids. At one year, 100% achieved improvement of visual acuity greater than or equal to 2 lines. On our service, 10 eyes (7 children) underwent cataract surgery. Seven were treated with systemic immunosuppressive drugs (aside from corticosteroids) and 80% of cases received oral corticosteroid therapy a few days before surgery. An intravenous corticosteroid bolus was administered preoperatively in 8 cases, and primary lens implantation was performed in 100% of cases. Postoperatively, 5 children received oral corticosteroid treatment. All were treated with local high dose steroids. At one year, the mean best-corrected visual acuity was 0.18 LogMar (0-0.7, SD: 0.25). CONCLUSION: When performed with an aggressive anti-inflammatory protocol, cataract surgery leads to a good visual outcome in selected children with chronic uveitis.

Real-World Experience and Impact of Canakinumab in Cryopyrin-Associated Periodic Syndrome: Results From a French Observational Study.

OBJECTIVE: The ENVOL study was designed to assess the psychosocial impact of disease and therapy in a French cohort of cryopyrin-associated periodic syndromes (CAPS) patients (and caregivers) treated with canakinumab. METHODS: The ENVOL study was a multicenter, observational study of CAPS patients given ≥1 canakinumab dose. Data were collected before treatment, at 6 and 12 months afterward, and at the last visit. Patients and caregivers completed questionnaires assessing changes from the 12 months of pretreatment to 12 months prior to interview. Data were analyzed retrospectively. RESULTS: The study included 10 physicians and 68 patients (53 adults, 15 children). Sixty-five patients (95.6%) were still receiving canakinumab at the last visit (median 5 years after starting therapy). The mean ± SD score for patient-reported general health increased from 7 ± 2.9 before canakinumab to 2.7 ± 2.7 after treatment (P < 0.001). Physical and emotional symptoms resolved or improved in a substantial proportion of patients, including bodily pain (38 of 46 patients), fever (32 of 39), skin disease (35 of 41), fatigue (31 of 47), self-confidence (29 of 46), and energy (34 of 47). Social activity, relationships, sexuality, and energy measures improved in >40% of respondents. Caregivers spent a median of 3 versus 0.5 hours/week on care in the 12 months of pretreatment versus 12 months prior to interview (P < 0.001). Following treatment, patients required fewer consultations with general practitioners (mean ± SD per patient per year: 5.2 ± 7.4 versus 8.5 ± 7.2 pretreatment), internists/rheumatologists/dermatologists (2.0 ± 2.1 versus 3.7 ± 3.9), and pediatricians (1.8 ± 1.5 versus 4.4 ± 4.2). CONCLUSION: Long-term treatment with canakinumab achieves a highly relevant improvement in the physical, emotional, and social lives of patients with CAPS, accompanied by a marked reduction in support required from caregivers and in health care consultations.

[Vaccinal status in children with seizures: a retrospective study conducted in the Bordeaux child hospital]. / Statut vaccinal d'enfants ayant un antécédent de convulsion ou d'épilepsie débutante: étude rétrospective comparative réalisée au CHU de Bordeaux.

UNLABELLED: Vaccination is a common act in medicine. Some serious side effects are always feared in a preventive action, mainly among high-risk patients such as epileptic children or children having already experienced a seizure. OBJECTIVES: To study consequences of such background on the vaccine medical practice. POPULATION AND METHODS: A retrospective study comparing the vaccine statute of children with or without case history of seizures was carried out by the neurologic and paediatric emergencies departments. The study compared 55 with seizures versus 109 without. RESULTS: On the whole, the 2 groups were insufficiently vaccinated. A statistically significant difference was highlighted between the 2 groups for the vaccination coverage by vaccine DTP (diphtheria-tetanus-pertussis) (P=0.017) and MMR (measles-mumps-rubella) (P=0.004). However, concerning the vaccination against hepatitis B, no difference was found. CONCLUSION: The usual contra-indications of these vaccines do not explain this difference and progress must be made to improve the vaccination coverage of epileptic children.

Ion microscopy based on laser-cooled cesium atoms.

We demonstrate a prototype of a Focused Ion Beam machine based on the ionization of a laser-cooled cesium beam and adapted for imaging and modifying different surfaces in the few-tens nanometer range. Efficient atomic ionization is obtained by laser promoting ground-state atoms into a target excited Rydberg state, then field-ionizing them in an electric field gradient. The method allows obtaining ion currents up to 130pA. Comparison with the standard direct photo-ionization of the atomic beam shows, in our conditions, a 40-times larger ion yield. Preliminary imaging results at ion energies in the 1-5keV range are obtained with a resolution around 40nm, in the present version of the prototype. Our ion beam is expected to be extremely monochromatic, with an energy spread of the order of the eV, offering great prospects for lithography, imaging and surface analysis.

Borromean three-body FRET in frozen Rydberg gases.

Controlling the interactions between ultracold atoms is crucial for quantum simulation and computation purposes. Highly excited Rydberg atoms are considered in this prospect for their strong and controllable interactions known in the dipole-dipole case to induce non-radiative energy transfers between atom pairs, similarly to fluorescence resonance energy transfer (FRET) in biological systems. Here we predict few-body FRET processes in Rydberg atoms and observe the first three-body resonance energy transfer in cold Rydberg atoms using cold caesium atoms. In these resonances, additional relay atoms carry away an energy excess preventing the two-body resonance, leading thus to a Borromean type of energy transfer. These few-body processes present strong similarities with multistep FRET between chromophores sometimes called donor-bridge-acceptor or superexchange. Most importantly, they generalize to any Rydberg atom and could lead to new implementations of few-body quantum gates or entanglement.

Spontaneous evolution of rydberg atoms into an ultracold plasma

We have observed the spontaneous evolution of a dense sample of Rydberg atoms into an ultracold plasma, in spite of the fact that each of the atoms may initially be bound by up to 100 cm(-1). When the atoms are initially bound by 70 cm(-1), this evolution occurs when most of the atoms are translationally cold, <1 mK, but a small fraction, approximately 1%, is at room temperature. Ionizing collisions between hot and cold Rydberg atoms and blackbody photoionization produce an essentially stationary cloud of cold ions, which traps electrons produced later. The trapped electrons rapidly collisionally ionize the remaining cold Rydberg atoms to form a cold plasma.

Photoassociative spectroscopy as a self-sufficient tool for the determination of the Cs triplet scattering length

In photoassociation spectroscopy, the line intensities of a given vibrational progression exhibit zero-signal modulation reflecting the node structure of the s-wave ground state wave function of two free colliding atoms. This leads to the determination of the scattering length. We performed photoassociation of cold Cs atoms polarized in the Zeeman sublevel f = 4, m(f) = 4. We analyzed the intensities of the lines associated with the Cs2 0(-)(g) state dissociating to the 6s(1/2)+6p(3/2) asymptote. This yields a value of the Cs triplet state scattering length, a(T) = -530a(0), while consistency requirements impose a value of the multipole ground state molecular coefficient, C6 = 6510 a.u.

The French version of the Childhood Health Assessment Questionnaire (CHAQ) and the Child Health Questionnaire (CHQ).

We report the results of the cross-cultural adaptation and validation into the French language of two health status instruments. The Childhood Health Assessment Questionnaire (CHAQ) is a disease specific instrument that measures functional ability in daily living activities in children with juvenile idiopathic arthritis (JIA). The Child Health Questionnaire (CHQ) is a generic health related quality of life instrument designed to capture the physical and psychosocial well-being of children independently from the underlying disease. Five hundred children were enrolled including 306 patients with JIA classified into systemic (23%), polyarticular (22%), extended oligoarticular (25%), and persistent oligoarticular (30%) subtypes, and 194 healthy children. Both instruments were reliable with intra-class correlation (ICC) coefficients for the test-retest procedure of 0.91 for the CHAQ, and 0.87 and 0.89 for the physical and psychosocial summary scores of CHQ, respectively. Agreement between parents and children evaluated for the CHAQ was high with an ICC of 0.89 for the disability index; weighted kappa coefficients for the 8 domains ranged from 0.61 to 0.72. Convergent validity was demonstrated by significant correlations with the JIA core set of variables (physician and parent global assessment, scores for active joints and joints with limited range of motion, erythrocyte sedimentation rate) for both instruments. Both CHAQ and CHQ discriminated between healthy and JIA children, but only the disease specific CHAQ questionnaire discriminated clearly between the 4 JIA subtypes. In conclusion, the French versions of the CHAQ and the CHQ are reliable, and valid health assessment questionnaires to be used in children suffering from JIA.

[(P)FAPA syndrome: value of cimetidine]. / (P)FAPA syndrome: intérêt de la cimétidine.

UNLABELLED: The (P)FAPA syndrome (periodic fever, adenitidis, pharyngitis, aphthous stomatitis) was described in 1987. The etiology of this periodic syndrome remains unknown. We report three new cases. CASE REPORTS: Three girls, aged from 23 months to eight years, developed (P)FAPA. The other causes of periodic fevers were eliminated and the various treatments (antibiotics, antipyretics, nonsteroidal anti-inflammatory agents) proved ineffective. The repetition of the periodic bouts resulted in depressive disorders, absenteeism from school and a drop in weight in the youngest patient. Two of them suffered a sinusal involvement (chronic sinusitis, polyp) and had an increase in the level of immunoglobulin A. In all three cases, cimetidine at a dose of 20 mg/kg/d was well tolerated and resulted in a disappearance of the periodic fevers. CONCLUSION: Cimetidine, as an immunomodulating agent, appears to be beneficial in the in-depth treatment of (P)FAPA syndrome.

[Familial idiopathic hypertrophic osteoarthropathy and atopic dermatitis (Currarino's disease)]. / Ostéoarthropathie hypertrophique primitive familiale et dermatite atopique (maladie de Currarino).

CASE REPORT: Two brothers with a Currarino's disease are reported. Patients characteristics included a dysmorphic syndrome, cranial suture defects, hypertrophic osteoarthropathy and severe chronic eczema. COMMENTS: Consanguinity of parents suggests an autosomal recessive inheritance. CONCLUSION: Currarino's disease is a rare unknown constitutional syndrome. The age of beginning of the disease, the cranial suture defects and the chronic eczema allow to distinguish it from the others primary hypertrophic osteoarthropathies.

[Neurocysticercosis: pediatric aspects]. / La neurocysticercose: particularités pédiatriques.

Neurocysticercosis is the most frequent parasitosis of the central nervous system in the world. Due to the extension of the pandemy, and the importance of the migrations from endemic countries, this parasitosis is being diagnosed with increasing frequency in France. Epilepsy is the main revealing symptom. However, in endemic countries, neurocysticercosis should be suspected in patients with any neurological sign. Diagnosis is based upon imaging procedures (computed tomography and magnetic resonance imaging) and serology (Elisa and Western blot). The evolution is highly variable, from complete latency to severe encephalopathy with psychomotor regression. Praziquantel and albendazole are the main therapeutic agents. Although corticosteroids are usually very effective on symptoms of the acute phase of the disease, their place in the treatment remains to be clarified. Racemic and ventricular forms of the disease usually need neurosurgery. In endemic regions, the diminution of the frequency of the disease relies upon prevention through health education compaigns, pending the achievement of an efficient vaccine.