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High-entropy-alloy (HEA) nanoparticles are attractive for several applications in catalysis and energy. Great efforts are currently devoted to establish composition-property relationships to improve catalytic activity or selectivity. Equally importantly, developing practical fabrication methods for shaping HEA-based materials into complex architectures is a key requirement for their utilization in catalysis. However, shaping nano-HEAs into hierarchical structures avoiding demixing or collapse remains a great challenge. Herein, we overcome this issue by introducing a simple soft-chemistry route to fabricate ordered macro- and mesoporous materials based on HEA nanoparticles, with high surface area, thermal stability, and catalytic activity toward CO oxidation. The process is based on spray-drying from an aqueous solution containing five different noble metal precursors and polymer latex beads. Upon annealing, the polymer plays a double role: templating and reducing agent enabling formation of HEA nanoparticle-based porous networks at only 350 °C. The formation mechanism and the stability of the macro- and mesoporous materials were investigated by a set of

Noble metal coordination xerogel films (mesostructured with block-copolymers) exhibit solubility switching with increasing X-ray irradiation. Different from other sol-gel systems, these are attributed to film deconstruction under irradiation. These materials can be used as recyclable negative tone resists for deep X-ray lithography that can be further converted into metallic nanoarchitectured films.

International audience; Solution-processed inorganic nanoporous films are key components for the vast spectrum of applications ranging from dew harvesting to solar cells. Shaping them into complex architectures required for advanced functionality, often need time-consuming or expensive fabrication. In this work, we show how crack formation is harnessed to pattern porous inorganic films in a single step and without using lithography. We developed aqueous ink formulations that, in the presence of polymeric latexes, enable evaporation-induced, defect-free periodic arrays of cracks with tunable dimensions over several centimeters. The ink formulation strategy was generalized to more than ten inorganic materials including simple and binary porous oxide and metallic films covering a whole spectrum of properties including insulator, photocatalytic, electrocatalytic, conductive or electrochromic materials. Notably, this approach enables three-dimensional self-assembly of cracks by stacking several layers of different compositions, yielding periodic assemblies of polygonal shapes and Janus-type patterns. The crack patterned periodic arrays of nanoporous TiO2 diffract light, and are used as temperature-responsive diffraction grating sensors. More broadly, this method represents a unique example of self-assembly process leading to long-range order (over several cm) in a robust and controlled way.

L’introduzione nella pratica clinica del dosaggio della copeptina come marcatore surrogato di arginin-vasopressina sta modificando radicalmente l’approccio diagnostico alle sindromi poliurico-polidipsiche, rendendo sempre meno utilizzato il test indiretto dell’assetamento. Un semplice dosaggio di copeptina al mattino a digiuno e in grado di diagnosticare con elevata accuratezza diagnostica il diabete insipido nefrogenico, mentre per distinguere il diabete insipido centrale dalla poliuria primaria e necessario ricorrere al dosaggio della copeptina stimolata con infusione di soluzione ipertonica 3% NaCl. Recentemente, e stato proposto di sostituire l’infusione di soluzione ipertonica con l’infusione di arginina e i primi dati sono certamente incoraggianti, ma si rimane in attesa di conferme da studi prospettici su vasta scala. L’impiego del dosaggio di copeptina nella diagnostica dell’iponatremia non e ancora entrato nella pratica clinica quotidiana. Tuttavia, alcuni studi indicano che il dosaggio di copeptina potrebbe essere utile, ad esempio, per distinguere alcuni sottogruppi di sindrome da inappropriata antidiuresi (SIAD) e, in associazione con la sodiuria, per individuare i pazienti ipovolemici. Mancano, comunque, conferme basate su evidenze piu nette.

Lo scopo di questa rassegna e fornire una visione generale dell’attuale stato della chirurgia ipofisaria e delle sue prospettive future, che possa essere utile ai differenti professionisti coinvolti nella gestione dei pazienti ipofisari per orientarsi nel rapido sviluppo di questo campo, anche per effetto dello sviluppo tecnologico. Oltre alla precisazione dei vantaggi, dei limiti, ma anche delle possibili evoluzioni, del rivoluzionario approccio endoscopico, verranno presentate anche le altre opzioni attualmente a disposizione della chirurgia. Saranno considerati quegli sviluppi tecnologici di imaging sia preoperatorio sia intraoperatorio che potranno caratterizzare il futuro prossimo della chirurgia ipofisaria, aumentandone ulteriormente le potenzialita, l’efficacia e la sicurezza, come la RM avanzata, i possibili sviluppi della radiomica, le applicazioni della realta aumentata e dell’Artificial Intelligence e il valore aggiunto di un nuovo modello organizzativo, rappresentato dalle Pituitary Units, comprendenti le differenti discipline coinvolte nella gestione delle patologie ipofisarie.

The control of magnetic properties at the nanoscale is a current topic of intense research. It was shown that combining both magnetic and plasmonic nanoparticles (NPs) led to the improvement of their magneto-optical signal. In this context, common strategies consist of the design of bimetallic NPs. However, the understanding of the physics leading to the coupling between magnetic and plasmonic NPs is lacking, preventing any significant progress for the development of future photonic devices. In this article, we propose to focus our attention on an efficient and commonly used magnetic metal, cobalt, and evaluate its plasmonic properties at the nanoscale through the use of NP regular arrays, as a potential candidate combining both optical and magnetic functionalities within the same metal. We show that such NPs display plasmonic properties within a large spectral range from the UV to the NIR spectral range, with efficient quality factors, when the inter-particle distance is properly selected. These as-fabricated simple materials could find applications in integrated photonic devices for telecommunications.

Objective Pituitary neuroendocrine tumours (PitNET)s can be aggressive, thus presenting local invasion, postsurgical recurrence and/or resistance to treatment, responsible for significant morbidity. The study aimed at identifying prognostic factors of postsurgical outcome using data-driven classification of patients.Design Retrospective observational study.Methods Clinicopathological and radiological data of patients with PitNET treated via endoscopic endonasal surgery were collected. Tumour recurrence/progression and progression-free survival were assessed by classification tree analysis (CTA) and Kaplan-Meier curves, respectively. Histological subtype, cavernous/sphenoid sinus invasion, mitosis, Ki-67, p53, Trouillas' grading, degree of tumour exeresis and postsurgery disease activity were also evaluated.Results A total of 1066 (466 gonadotroph, 287 somatotroph, 148 lactotroph, 157 corticotroph and 8 thyrotroph) tumours were included; 21.7% invaded the cavernous/sphenoid sinus. Based on Trouillas' classification, 64.3% were grade 1a, 14.2% 1b, 16.1% 2a, and 5.4% 2b; 18.3% had >2/10 HPF mitoses, 24.9% had Ki-67 >= 3%; 15.8% were positive for p53. Exeresis was radical in 81.2% of the cases. Median follow-up was 59.2 months. At last evaluation, 79.4% of the patients were cured; 20.6% had disease persistence, controlled by medical treatment in 18.3% of them. Disease recurrence/progression was recorded in 10.9% of the cases. CTA identified 5 distinct patient subgroups with different risk of disease recurrence/progression. Grade 2 of the Trouillas' grading, >2/10 HPF mitoses, Ki-67 >= 3%, p53 protein expression (P < .001), tumour invasion (P = .002) and ACTH-subtype (P = .003) were identified as risk factors of disease recurrence/progression.Conclusions The combined evaluation of Trouillas' grading, proliferation indexes and immunohistochemistry appears promising in the prediction of surgical outcome in PitNET.

Purpose Biochemical remission (BR), gross total resection (GTR), and intraoperative cerebrospinal fluid (CSF) leaks are important metrics in transsphenoidal surgery for acromegaly, and prediction of their likelihood using machine learning would be clinically advantageous. We aim to develop and externally validate clinical prediction models for outcomes after transsphenoidal surgery for acromegaly. Methods Using data from two registries, we develop and externally validate machine learning models for GTR, BR, and CSF leaks after endoscopic transsphenoidal surgery in acromegalic patients. For the model development a registry from Bologna, Italy was used. External validation was then performed using data from Zurich, Switzerland. Gender, age, prior surgery, as well as Hardy and Knosp classification were used as input features. Discrimination and calibration metrics were assessed. Results The derivation cohort consisted of 307 patients (43.3% male; mean [SD] age, 47.2 [12.7] years). GTR was achieved in 226 (73.6%) and BR in 245 (79.8%) patients. In the external validation cohort with 46 patients, 31 (75.6%) achieved GTR and 31 (77.5%) achieved BR. Area under the curve (AUC) at external validation was 0.75 (95% confidence interval: 0.59–0.88) for GTR, 0.63 (0.40–0.82) for BR, as well as 0.77 (0.62–0.91) for intraoperative CSF leaks. While prior surgery was the most important variable for prediction of GTR, age, and Hardy grading contributed most to the predictions of BR and CSF leaks, respectively. Conclusions Gross total resection, biochemical remission, and CSF leaks remain hard to predict, but machine learning offers potential in helping to tailor surgical therapy. We demonstrate the feasibility of developing and externally validating clinical prediction models for these outcomes after surgery for acromegaly and lay the groundwork for development of a multicenter model with more robust generalization.

Gelled mediums were widely used during the nineteenth century, added to paint on the palette to modify its rheological, optical, and drying properties. Many variations of gelled mediums exist in the literature, all with the common basis of mastic resin or varnish, drying oil, and a lead compound. With the aim of unveiling the chemistry of such systems, reconstructions were carried out not only following the historical recipes, but in addition, exploring variations and simplifications to get a better understanding of the key ingredients and interactions inducing gelation. Different parameters were tested to establish whether these have an impact on the gelation mechanisms, particularly the influence of the nature and proportions of the ingredients and the preparation process. These reconstructions and their FTIR characterisation reveal the formation of metal-resin soaps, but also underline the specific role of lead in the gelation.

Prolactinomas are the most frequent pituitary adenomas. Prolactinoma may occur in different clinical settings and always require an individually tailored approach. This is the reason why a panel of Italian neuroendocrine experts was charged with the task to provide indications for the diagnostic and therapeutic approaches that can be easily applied in different contexts. The document provides 15 recommendations for diagnosis and 54 recommendations for treatment, issued according to the GRADE system. The level of agreement among panel members was formally evaluated by RAND-UCLA methodology. In the last century, prolactinomas represented the paradigm of pituitary tumors for which the development of highly effective drugs obtained the best results, allowing to avoid neurosurgery in most cases. The impressive improvement of neurosurgical endoscopic techniques allows a far better definition of the tumoral tissue during surgery and the remission of endocrine symptoms in many patients with pituitary tumors. Consequently, this refinement of neurosurgery is changing the therapeutic strategy in prolactinomas, allowing the definitive cure of some patients with permanent discontinuation of medical therapy.

International audience; Due to their high porosity and chemical versatility, metal-organic frameworks (MOFs) exhibit physical properties appealing for photonic-based applications. While several MOF photonic structures have been reported, examples of applications thereof are mainly limited to chemical sensing. Herein, the range of application of photonic MOFs is extended to local thermal and photothermal sensing by integrating them into a new architecture: MOF photonic balls. Micrometric-sized photonic balls are made of monodispersed MOFs colloids that are self-assembled via spray-drying, a low-cost, green, and high-throughput method. The versatility of the process allows tuning the morphology and the composition of photonic balls made of several MOFs and composites with tailored optical properties. X-ray nanotomography and environmental hyperspectral microscopy enable analysis of single objects and their evolution in controlled atmosphere and temperature. Notably, in presence of vapors, the MOF photonic balls act as local, label-free temperature probes. Importantly, compared to other thermal probes, the temperature detection range of these materials can be adjusted "on-demand." As proof of concept, the photonic balls are used to determine local temperature profiles around a concentrated laser beam. More broadly, this work is expected to stimulate new research on the physical properties of photonic MOFs providing new possibilities for device fabrication.

Combining high activity and stability, iridium oxide remains the gold standard material for the oxygen evolution reaction in acidic medium for green hydrogen production. The reasons for the higher electroactivity of amorphous iridium oxides compared to their crystalline counterpart is still the matter of an intense debate in the literature and, a comprehensive understanding is needed to optimize its use and allow for the development of water electrolysis. By producing iridium-based mixed oxides using aerosol, we are able to decouple the electronic processes from the structural transformation, i.e. Ir oxidation from IrO2 crystallization, occurring upon calcination. Full characterization using in situ and ex situ X-ray absorption spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction and transmission electron microscopy allows to unambiguously attribute their high electrochemical activity to structural features and rules out the iridium oxidation state as a critical parameter. This study indicates that short-range ordering, corresponding to sub-2nm crystal size for our samples, drives the activity independently of the initial oxidation state and composition of the calcined iridium oxides., The origins of the superior catalytic activity of poorly crystallized Ir-based oxide material for the OER in acid is still under debate. Here, authors synthesize porous IrMo oxides to deconvolute the effect of Ir oxidation state from short-range ordering and show the latter to be a key factor.

Introduction: Endobronchial ultrasound (EBUS) is an endoscopic diagnostic procedure combining flexible fibrobronchoscopy with ultrasound techniques; it allows transbronchial needle aspiration biopsy for the diagnosis and staging of mediastinal masses. We present our preliminary experience with the use of the i-gel O2 supraglottic airway device for management of EBUS procedures. Methods: An observational study on 39 patients who underwent EBUS under general anesthesia was performed. Airways were managed with i-gel O2 by anesthesiologists unfamiliar with it. Data collected included patient characteristics, i-gel O2 positioning, mechanical ventilation, procedure, and complications occurring during and after the EBUS. Results: The i-gel airway was successfully positioned during the first attempt in 34/39 cases (87.2%). No failed positioning was recorded. The EBUS scope easily passed through the i-gel in all patients and in 14 (35.6%) cases it was also inserted through the esophagus allowing the examination or fine needle aspiration of paraesophageal lymph nodes. In one case, during the EBUS procedure, the i-gel was dislocated but easily put in place again. During EBUS, air leakages were significant in 2 cases (5.1%) and minimal in 14 cases (35.9%). A brief self-solved laryngospasm and a bronchospasm during bronchoscopy were recorded. After recovery, no patients had dysphagia; mild odynophagia and pharyngodinia were referred by 2 (5.1%) and 12 (30.1%) patients, respectively. Conclusions: The i-gel O2 airway is easy to position and manage even for anesthesiologists unfamiliar with it. This supraglottic airway device is suitable for a complete endosonographic evaluation of the mediastinum.

Objective and design A clinicopathological score has been proposed by Trouillas et al. to predict the evolution of pituitary adenomas. Aim of our study was to perform an independent external validation of this score and identify other potential predictor of post-surgical outcome. Methods The study sample included 566 patients with pituitary adenomas, specifically 253 FSH/LH-secreting, 147 GH-secreting, 85 PRL-secreting, 72 ACTH-secreting and 9 TSH-secreting tumours with at least 3-year post-surgical follow-up. Results In 437 cases, pituitary adenomas were non-invasive, with low (grade 1a: 378 cases) or high (grade 1b: 59 cases) proliferative activity. In 129 cases, tumours were invasive, with low (grade 2a: 87 cases) or high (grade 2b: 42 cases) proliferative activity. During the follow-up (mean: 5.8 years), 60 patients developed disease recurrence or progression, with a total of 130 patients with pituitary disease at last follow-up. Univariate analysis demonstrated a significantly higher risk of disease persistence and recurrence/progression in patients with PRL-, ACTH- and FSH/LH-secreting tumours as compared to those with somatotroph tumours, and in those with high proliferative activity (grade 1b and 2b) or >1 cm diameter. Multivariate analysis confirmed tumour type and grade to be independent predictors of disease-free-survival. Tumour invasion, Ki-67 and tumour type were the only independent prognostic factors of disease-free survival. Conclusions Our data confirmed the validity of Trouillas’ score, being tumour type and grade independent predictors of disease evolution. Therefore, we recommend to always consider both features, together with tumour histological subtype, in the clinical setting to early identify patients at higher risk of recurrence.

Proton-exchange membrane water electrolyzers (PEMWEs) electrodes use scarce and costly platinum group metals (PGMs), but only such devices are able to meet the requirements associated with renewable energies (large amplitude and frequent and rapid variations in the current applied to the cell). Catalysts represent only 8 % to the overall stack cost, 6 % being associated with the high iridium (Ir) loading used to electrocatalyze the anodic oxygen evolution reaction (OER). High surface area supported Ir oxide (IrOx) catalysts thus represent a promising strategy to reduce the cost of this technology and limit the geological pressure on Ir. However, the Gibbs-Thompson effect, which controls the electrochemical stability of nanomaterials casts a doubt on the viability of this approach. To shed light into the benefits and limitations of supported and unsupported IrOx catalysts, we benchmarked commercial materials (unsupported IrO2, Ir/C), unsupported porous IrOx microparticles, and IrOx nanoparticles (NPs) supported on carbon black or on doped tin oxide aerogels (AG)/nanofibers (NFs). Transmission electron microscopy (TEM) and identical-location transmission electron microscopy (IL-TEM) provided changes in morphology during accelerated stress testing. Complementarily, a flow cell connected to an inductively-coupled mass spectrometer (FC-ICP-MS) was used to assess their stability number (S-number, see Figure 1). The results show that supported IrOx nanocatalysts are extremely active toward the OER because they feature mixed Ir oxidation states and a high density of active sites (small crystallite/particle size). The lack of robustness of their supports, however, prevents the nanocatalysts from sustaining this high OER activity [1, 2]. Similar to what was observed on extended surfaces, we report that mild thermal annealing (450°C) leads to lower Ir atom dissolution rate. Overall, the best compromise between OER activity and stability was obtained for unsupported porous IrOx microparticles after mild thermal annealing under air at 450°C [2]. On the cathode side, IL-TEM measurements revealed mild changes in morphology for Pt/C nanoparticles [3]. Ackowledgements This work was supported by the French National Research Agency in the frame of the MOISE project (grant number ANR-17-CE05-0033). References S. Abbou, R. Chattot, V. Martin, F. Claudel, L. Solà-Hernández, C. Beauger, L. Dubau, F. Maillard, ACS Catal. 10 (2020) 7283-7284. C. Daiane Ferreira da Silva, F. Claudel, V. Martin, R. Chattot, S. Abbou, K. Kumar, I. Jiménez-Morales, S. Cavaliere, D. Jones, J. Rozière, L. Solà-Hernandez, C. Beauger, M. Faustini, J. Peron, B. Gilles, C. Beauger, L. Piccolo, F. H. Barros de Lima, L. Dubau, F. Maillard, ACS Catal. 11 (2021) 4107-4116. A. Viola, L. Dubau, F. Maillard, in preparation. Figure 1. S-number values calculated for supported and unsupported IrOx electrocatalysts during a galvanostatic accelerated stress test (j = 10 mA cm-2 geo, T = 80 °C, U cut-off = 2 V vs. RHE) performed in Ar-saturated 0.05 M H2SO4. Reprinted with permission from ref. [2]. Copyright 2021 American Chemical Society. Figure 1

We demonstrated recently a record 19.9%-efficient GaAs solar cell with an absorber thickness of only 200 nm. Our next step is to optimize the device to reach a 25% efficiency. In this contribution we will present our latest simulation and experimental results based on an extensive analysis of the optical and electrical losses. The benefits brought by the contacts optimization and the improvement of the nanostructured design at the rear side of the solar cell will be emphasized.

International audience; Metal-Assisted Chemical Etching (MACE) has emerged as effective method to fabricate high aspect ratio nanostructures. This method requires a catalytic mask that is generally composed by a metal. Here, we challenge the general view that the catalyst needs to be metal by introducing Oxide-assisted Chemical Etching (OACE). We perform etching with metal oxides such as RuO 2 and IrO 2 , by transposing materials used in electrocatalysis to nanofabrication. These oxides can be solution-processed as polymers exhibiting similar capabilities of metals for MACE. Nanopatterned oxides can be obtained by direct nanoimprint lithography or blockcopolymer lithography from chemical solution on large scale. High aspect ratio silicon nanostructures were obtained at the sub-20 nm scale exclusively by cost-effective solution processing by halving the number of fabrication steps compared to MACE. More in general, OACE is expected to stimulate new fundamental research on chemical etching assisted by other materials providing new possibilities for device fabrication.

We propose an easy and low-cost bonding method for III-V//Si tandem solar cells, based on conductive sol-gel-derived and hybrid materials. The design enables current matching and photon recycling. First prototypes have been demonstrated successfully.

International audience; Advanced materials are needed to meet the requirements of devices designed for harvesting and storing renewable electricity. In particular, polymer electrolyte membrane water electrolyzers (PEMWEs) could benefit from a reduction in the size of the iridium oxide (IrO x) particles used to electrocatalyze the sluggish oxygen evolution reaction (OER). To verify the validity of this approach, we built a library of 18 supported and unsupported IrO x catalysts and established their stability number (S-number) values using inductively coupled plasma mass spectrometry and electrochemistry. Our results provide quantitative evidence that (i) supported IrO x nanocatalysts are more active toward the OER but less stable than unsupported micrometer-sized catalysts, for example, commercial IrO 2 or porous IrO x microparticles; (ii) tantalum-doped tin oxides (TaTO) used as supports for IrO x nanoparticles are more stable than antimony-doped tin oxides (ATO) and carbon black (Vulcan XC72); (iii) thermal annealing under air atmosphere yields depreciated OER activity but enhanced stability; (iv) the beneficial effect of thermal annealing holds both for micro-and nano-IrO x particles and leads to 1 order of magnitude lower Ir atom dissolution rate with respect to nonannealed catalysts; (v) the best compromise between OER activity and stability was obtained for unsupported porous IrO x microparticles after thermal annealing under air at 450°C. These insights provide guidance on which material classes and strategies are the most likely to increase sustainably the OER efficiency while contributing to diminish the cost of PEMWE devices.

Hypopituitarism seems to be rather common following aneurysmal subarachnoid haemorrhage (aSAH), even though its real prevalence remains unclear and the effects on six-month patient functional outcomes are debatable. This study correlated hypopituitarism after aSAH and cognitive performances using neuropsychological tests.In a prospective cohort of patients with aSAH, basal pituitary hormone testing was undergone and two neuropsychological tests, Montreal Cognitive Assessment (MoCA) and Mini Mental Status Examination (MMSE), were administered in three phases: in the subacute phase (2 weeks), the chronic phase (3-6 months) and the follow-up phase (6-12 months) post aSAH.Twenty-five patients were enrolled in the study. Considering the median values of MMSE and MoCA in the subacute phase there was an association with hypo-free triiodothyronine (fT3) (p = 0.03, p = 0.03), hypo-luteinizing hormone (LH) (p = 0.002, p = 0.0002), hypo-follicle stimulating hormone (FSH) (p = 0.002, p = 0.002) and hypo-testosterone (p = 0.02, p = 0.05) respectively. Similarly, in the chronic phase we found an association of median values of MMSE and MoCA with hypo-free thyroxine (fT4) (p = 0.03, p = 0.03), hypo-LH (p = 0.03, p = 0.03) and hypo-FSH (p = 0.03, p = 0.03), respectively. Finally, in the follow-up phase, MMSE and MoCA correlated with hypo-fT4 (p = 0.03, p = 0.03), hypo-LH (p = 0.05, p = 0.05) and hypo-FSH (p = 0.05, p = 0.05), respectively.For aSAH patients in the post-acute phase, neuropsychological tests can represent an inexpensive tool to confirm cognitive impairment, which can be associated with neuroendocrine dysfunction.

Single crystals and thin films of metal–organic frameworks can now be directly patterned by lithography down to the sub-50-nm scale, enabling straightforward integration in solid-state devices.

International audience; For several decades, the sol-gel process allows the fabrication of functional materials through the strong coupling between materials chemistry and advanced processing. This branch of material's science is generally associated to the formation of oxide and hybrid materials obtained through a transition between a sol and a gel. Engineering the sol-gel process to extend same principles to other classes of materials is an emerging and promising research line. These aspects will be illustrated in this article by reviewing the successful case of optical materials with tunable structural colors. It will be shown that sol-gel transition from molecular or colloidal building blocks results in optical materials with great diversity in structure and composition such as oxide, hybrid or, Metal Organic Frameworks. Applicative examples will be provided including photocatalytic, "invisible" and anti-reflective coatings, graded photonic mirrors and 2D photonic sensors.

International audience; Living tissues, heterogeneous at the microscale, usually scatter light. Strong scattering is responsible for the whiteness of bones, teeth, and brain and is known to limit severely the performances of biomedical optical imaging. Transparency is also found within collagen-based extracellular tissues such as decalcified ivory, fish scales, or cornea. However, its physical origin is still poorly understood. Here, we unveil the presence of a gap of transparency in scattering fibrillar collagen matrices within a narrow range of concentration in the phase diagram. This precholesteric phase presents a three-dimensional (3D) orientational order biomimetic of that in natural tissues. By quantitatively studying the relation between the 3D fibrillar network and the optical and mechanical properties of the macroscopic matrices, we show that transparency results from structural partial order inhibiting light scattering, while preserving mechanical stability, stiffness, and nonlinearity. The striking similarities between synthetic and natural materials provide insights for better understanding the occurring transparency.

Engineering photothermal effects in plasmonic materials is of paramount importance for many applications, such as cancer therapy, chemical synthesis, cold catalysis and, more recently, metasurfaces. The evaluation of plasmonic heating at the nanoscale is challenging and generally requires sophisticated equipments and/or temperature-sensitive probes such as fluorescent molecules or materials. Here, we propose to use water vapor as a probe to evaluate the local heating around plasmonic nanoparticles. We demonstrate the concept for the case of a plasmonic colloidal film characterized by bi-modal nanoporosity. In particular, we exploit the thermal and light water liquid–vapor phase transitions taking place in the nanoporous medium that can be triggered by external stimuli, such as heating or irradiation, to obtain structural and optical variations in the film. The local temperature is then estimated using spectroscopic ellipsometry data acquired by a multimodal chamber. More generally, this method offers a simple and general approach to determine the local temperature that only requires a nanoporous material and water vapor, such as environmental humidity. In addition, this approach can be further generalized to other materials, vapor molecules or optical techniques.

International audience; Mesoporous silica nanoparticles (MSNs) have seen a fast development as drug delivery carriers thanks to their tunable porosity and high loading capacity. The employ of MSNs in biomedical applications requires a good understanding of their degradation behavior both to control drug release and to assess possible toxicity issues on human health. In this work, we study mesoporous silica degradation in biologically relevant conditions through in situ ellipsometry on model mesoporous nanoparticle or continuous thin films, in buffer solution and in media containing proteins. In order to shed light on the structure/dissolution relationship, we performed dissolution experiments far from soluble silicate species saturation. Via a complete decorrelation of dissolution and diffusion contributions, we proved unambiguously that surface area of silica vectors is the main parameter influencing dissolution kinetics, while thermal treatment and open mesoporous network architecture have a minor impact. As a logical consequence of our dissolution model, we proved that the dissolution lag-time can be promoted by selective blocking of the mesopores that limits the access to the mesoporous internal surface. This study was broadened by studying the impact of the organosilanes in the silica structure, of the presence of residual structuring agents, and of the chemical composition of the dissolution medium. The presence of albumin at blood concentration was found affecting drastically the dissolution kinetics of the mesoporous structure, acting as a diffusion barrier. Globally, we could identify the main factors affecting mesoporous silica materials degradation and proved that we can tune their structure and composition for adjusting dissolution kinetics in order to achieve efficient drug delivery.

International audience; Porous noble metal nanostructures providing high surface areas and large pore volumes are attractive for numerous applications especially catalysis. However, the synthesis of such architectures with nanoscale features is challenging because of i.e high surface energy. Previous reports are based on multi-step synthetic approaches with low yield thus not compatible with industrial scale. Herein, we demonstrate that hierarchical nanostructured noble metals and alloys, with thermal stability up to 800 °C, can be fabricated by a high throughput, green and straightforward aerosol-assisted synthesis using bi-functional reducing templates. We unravel the reduction mechanism at the solid/solid interface at the single-particle level using state-of-the-art techniques such as in situ Transmission Electron Microscopy, in situ synchrotron-based X-ray absorption spectroscopy. We propose a mechanism based on a radical process thermally triggered by the depolymerization of organic components. From a fundamental point of view, this study sheds light on the reduction processes of noble metals in the presence of organic compounds with important fundamental implications for catalysis and electrocatalysis.

Endoscopic endonasal represents an expanding surgical approach for craniopharyngiomas, thanks to the recent technological innovation and advancement in the endoscopic technique. This approach has the advantages to permit to reach these complex tumors through a complete extra cranial route, avoiding brain retraction and vasculo-nervous structures manipulation, giving a wide and panoramic surgical view of the suprasellar region.

Background In the last years, few reports have shown the feasibility of the endoscopic endonasal approach (EEA) for craniopharyngiomas in pediatric patients. For these tumors, recent studies have suggested less aggressive surgery, favoring the preservation of the patient's quality of life. Objective The aim of this study was to assess the outcome of the EEA in a large series with specific attention on the long-term functional sequelae. Materials All consecutive pediatric craniopharyngiomas operated on through this approach since 2000 were included in the study. Preoperative and postoperative operative clinical, radiologic, and pathologic features were retrieved from patient records (mean follow-up, 72 ± 67 months). Results The series included 25 patients (12 female; mean age, 8.9 ± 4.1 years). Most of the tumors presented with a supradiaphragmatic extension (88%). Removal was radical in 23 patients (92%). Complications consisted of 6 cerebrospinal fluid leaks (24%). One patient (4%) died of postoperative respiratory complications. Most patients (92%) developed panhypopituitarism and visual disturbances normalized or improved in 6 patients (43%). At follow-up, 9 patients (36%) were overweight/obese (6 were already overweight before surgery). The tumor recurrence rate was 19%. Conclusions EEA can be an effective approach for midline craniopharyngiomas in children older than 3 years. It gives a satisfactory exposure of the suprasellar region and an adequate assessment of the brain–tumor interface. Its main limitations are age-related anatomic features of nasal/paranasal sinuses and the risk of cerebrospinal fluid leak.

Myasthenia gravis (MG) is an autoimmune disease affecting neuromuscular transmission that manifests with muscle weakness and typically involves the eye muscles, often producing diplopia and ptosis. Recent studies suggest that hyperprolactinaemia may have a role in the development of MG, although its association with prolactinoma is extremely rare. We report the unusual case of a 71-year-old male affected with macroprolactinoma, who presented at our Center 2 weeks after starting cabergoline treatment because of acute onset of headache, diplopia, and ptosis. On admission, he presented with drowsiness, dropped head, swallowing impairment and bilateral ptosis, which rapidly worsened. Based on clinical manifestation and history, emergency surgery was performed on suspicion of pituitary apoplexy (PA), the typical complication occurring in patients with macroadenomas who present these symptoms. No pituitary haemorrhage was found. The symptoms initially resolved after surgery, but soon returned and worsened day by day, especially in the evening, despite the increase of cortisone replacement doses. MG was thus suspected and confirmed by the detection of antibodies to the acetylcholine receptor. Pyridostigmine was started with prompt improvement of neurological symptoms. In conclusion, although very rare, MG should be considered in the differential diagnosis of patients with macroprolactinomas and suggestive neurological symptoms in order to provide early and appropriate treatment. The role of hyperprolactinaemia in MG onset and evolution is also discussed.

This study aimed to quantify 24 h body core temperature (BcT°) and sleep-wake cycle rhythm alterations in craniopharyngioma (CP) patients and to identify markers related to the postsurgical outcomes. Ten consecutive CP patients underwent neuroradiological, endocrinological and ophthalmological evaluations, 24 h BcT° and sleep-wake cycle recordings before and after endoscopic endonasal surgery. The sample included four women and six men. Nocturnal sleep efficiency was pathologically reduced in eight patients before surgery. Seven out of ten patients presented one to three daytime naps. 24 h BcT° rhythm was pathological in six out of ten cases. Post-surgery sleep efficiency normalized in four out of eight patients, whereas nine out of ten patients presented with two to six longer daytime naps. Diurnal naps were mainly present in patients showing pre-operative involvement of the third ventricle floor. 24 h BcT° remained pathological in only one out of six cases, returned to normal in two and improved in three. 24 h BcT° rhythm improved more in papillary CPs than in adamantomatous CPs. Our data confirmed that both CP and surgery frequently disrupt the sleep-wake cycle and BcT° rhythms. Tumour location and histotype may be related to a worse postsurgical outcome. Therefore, in-depth investigation including circadian monitoring is crucial for surgical outcome.

International audience; British 19th century painters formulated gelled systems often described as ideal paint mediums. These so-called megilps or gumtions are based on common paint materials like linseed oil, lead acetate, and mastic resin, and allowed painters such as J.M.W Turner to improve their paint's properties and achieve unprecedented effects in an age of innovation. To propose a structural scheme of these hybrid systems of unprecedented complexity, it is paramount to design and study model systems using a broad combination of advanced spectroscopic techniques and microscopies. Through this approach, gel Mediums can be described as nanocomposites based on lead metallogels co-existing with lead oxide nanoparticles and a partially polymerized fraction. These functional hybrid materials created a real breakthrough on 19th century paints performances.

The performance of Proton Exchange Membrane Electrolyzers (PEMWE) is mostly impeded by the efficiency of the anode catalysts allowing for the Oxygen Evolution Reaction (OER) to occur. New catalytic materials should possess at least as high performance and stability as state of the art materials, since the price of electrolysis is mostly impacted by the price of electricity and higher overpotentials would render the catalysts not viable for application in PEMWE. The use of noble metal at the anode for the OER is at the current stage essential due to the highly oxidative and strongly acidic environment. Nevertheless, due to cost and resources considerations, it is necessary to reduce the noble metal content. In addition, according to present industrial requirements, PEMWE cells should be able to work at very high current density and under high pressure. Water and gases management are also a major challenge in PEMWE catalyst layers, and unlike in fuel cells or PEMWE cathodes the use of a cheap carbon based porous support for electronic conduction at the anode is highly undesirable due to highly anodic potential. We have developed a cheap, clean and easily scalable synthesis method to produce highly porous iridium-based materials. The materials are synthesized in aqueous solutions in presence of a porogen. The resulting material is further calcinated to remove the porogen and initiate crystallization of the inorganic phase. By adjusting reactant concentrations and calcination conditions, metallic iridium, iridium oxide or mixed oxides can be obtained. This last point is of high importance since in addition to reducing noble metals content compared to current technologies, the atomic neighborhood of dissimilar metals is expected to modify the monometallic behavior and potentially gives rise to new desired characteristics, i.e.to decrease the OER overpotential and/or increase the material stability. Structural characteristics and chemical composition of the materials have been determined using XRD, XPS and XRF. The influence of the thermal treatment has a strong impact on the crystallite size and the composition of the particle surface. SEM-FEG and BET characterizations have shown that the type of the porogen used for material synthesis directly impacts its morphology and porosity. To assess the catalytic performances of these hierarchically porous materials, a screening of the electrocatalytic activity of a series of prepared materials has been performed using a three-electrodes electrochemical setup. The optimized material shows lower overpotential than commercial Ir or IrO2 nanoparticles as shown on the figure thereafter. Finally, selected materials have been used to prepare anode catalyst layers and have been tested in a complete electrolysis device. With a loading of 2 mg cm-2 in Iridium, a potential of 1.65 V at 1 A cm-2 and of 1.85 V at 2 A cm-2 is obtained. The produced specific morphologies are very well adapted to the formation of porous percolating networks, which promote gases and water transport throughout the catalyst layer. Figure 1