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1.
PLoS One ; 19(8): e0309093, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39172817

RESUMO

Network Signalling Data (NSD) have the potential to provide continuous spatio-temporal information about the presence, mobility, and usage patterns of cell phone services by individuals. Such information is invaluable for monitoring large urban areas and supporting the implementation of decision-making services. When analyzed in real time, NSD can enable the early detection of critical urban events, including fires, large accidents, stampedes, terrorist attacks, and sports and leisure gatherings, especially if these events significantly impact mobile phone network activity in the affected areas. This paper presents empirical evidence that advanced NSD can detect anomalies in mobile traffic service consumption, attributable to critical urban events, with fine spatial (a spatial resolution of a few decameters) and temporal (minutes) resolutions. We introduce two methodologies for real-time anomaly detection from multivariate time series extracted from large-scale NSD, utilizing a range of algorithms adapted from the state-of-the-art in unsupervised machine learning techniques for anomaly detection. Our research includes a comprehensive quantitative evaluation of these algorithms on a large-scale dataset of NSD service consumption for the Paris region. The evaluation uses an original dataset of documented critical or unusual urban events. This dataset has been built as a ground truth basis for assessing the algorithms' performance. The obtained results demonstrate that our framework can detect unusual events almost instantaneously and locate the affected areas with high precision, largely outperforming random classifiers. This efficiency and effectiveness underline the potential of NSD-based anomaly detection in significantly enhancing emergency response strategies and urban planning. By offering a proactive approach to managing urban safety and resilience, our findings highlight the transformative potential of leveraging NSD for anomaly detection in urban environments.


Assuntos
Algoritmos , Telefone Celular , Humanos , Paris , Cidades
2.
J Clin Invest ; 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39207851

RESUMO

BACKGROUND: Donor cell engraftment is a pre-requisite of successful allogeneic hematopoietic stem cell transplantation. Based on peripheral blood analyses it is characterized by early myeloid recovery and T- and B-cells lymphopenia. However, cellular networks associated with bone marrow engraftment of allogeneic human cells have been poorly described. METHODS: Mass cytometry and CITEseq analyses were performed on bone marrow cells, three months post-transplant in patients with acute myelogenous leukemia. RESULTS: Mass cytometry in 26 patients and 20 healthy controls disclosed profound alterations in myeloid and B-cell progenitors, with a shift towards terminal myeloid differentiation and decreased B-cell progenitors. Unsupervised analysis separated recipients into 2 groups, one of them being driven by previous GVHD (R2 patients). We then used single-cell CITEseq to decipher engraftment, which resolved 36 clusters, encompassing all bone marrow cellular components. Hematopoiesis in transplant recipients was sustained by committed myeloid and erythroid progenitors in a setting of monocytes-, NK cells- and T-cells mediated inflammation. Gene expression disclosed major pathways in transplant recipients, namely, TNFα signaling via NFκ-B, and interferon-γ response. The hallmark of allograft rejection was consistently found in clusters from transplant recipients, especially in R2 recipients. CONCLUSION: Bone marrow cell engraftment of allogeneic donor cells is characterized by a state of emergency hematopoiesis in the setting of allogeneic response driving inflammation. TRIAL REGISTRATION: Not applicable. FUNDING: This study has been supported by the French National Cancer Institute (Institut National du Cancer): PLBIO19-239 and by an unrestricted research grant by Alexion Pharmaceutical.

3.
J Med Virol ; 96(8): e29836, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39078052

RESUMO

Primary effusion lymphoma (PEL) is a rare B-cell non-Hodgkin lymphoma associated with Kaposi Sarcoma-associated herpesvirus (KSHV/HHV8) infection. Lymphoma cells are coinfected with Epstein-Barr virus (EBV) in 60-80% of cases. Tools allowing a reliable PEL diagnosis are lacking. This study reports PEL diagnosis in 4 patients using a Flow-Fluorescence in situ hybridization (FlowFISH) technique that allowed detection of differentially expressed EBV and HHV8 transcripts within the same sample, revealing viral heterogeneity of the disease. Moreover, infected cells exhibited variable expressions of CD19, CD38, CD40, and CD138. Therefore, FlowFISH is a promising tool to diagnose and characterize complex viral lymphoproliferations.


Assuntos
Herpesvirus Humano 4 , Herpesvirus Humano 8 , Hibridização in Situ Fluorescente , Linfoma de Efusão Primária , Humanos , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/isolamento & purificação , Hibridização in Situ Fluorescente/métodos , Linfoma de Efusão Primária/virologia , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Masculino , Idoso , Pessoa de Meia-Idade , Feminino , Infecções por Herpesviridae/virologia , Infecções por Herpesviridae/diagnóstico , Infecções por Vírus Epstein-Barr/virologia , Infecções por Vírus Epstein-Barr/complicações , Idoso de 80 Anos ou mais
4.
Small Methods ; : e2400472, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856032

RESUMO

Advancements in operando techniques have unraveled the complexities of the Electrode Electrolyte Interface (EEI) in electrochemical energy storage devices. However, each technique has inherent limitations, often necessitating adjustments to experimental conditions, which may compromise accuracy. To address this challenge, a novel battery cell design is introduced, integrating piezoelectric sensors with electrochemical analysis for surface-sensitive operando measurements. This innovative approach aims to overcome conventional limitations by accommodating commercial-grade battery electrodes within a single body, alongside a piezoelectric sensor. This enables operando electrogravimetric measurements to be realized, and the electrochemistry of a battery to be more faithfully reproduced at the sensor level. A proof of concept is carried out on both Li-ion (LiFePO4//Graphite) and Na-ion (Na3V2(PO4)2F3//Hard carbon) systems, utilizing commercially available powder electrodes. In both cases, the results reveal rational mass variations at the sensor level during the cycling of commercial electrodes with mass loadings several orders of magnitude higher, while performing Galvanostatic Charge Discharge (GCD) tests across various C-rates. This innovative design opens up possibilities for a broader application of operando electrogravimetry within the battery community, to enhance the understanding of EEI behavior and facilitate the development of more efficient energy storage solutions.

6.
Neurobiol Dis ; 188: 106345, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37926170

RESUMO

The neocortex is highly susceptible to metabolic dysfunction. When exposed to global ischemia or anoxia, it suffers a slowly propagating wave of collective neuronal depolarization that ultimately impairs its structure and function. While the molecular signature of anoxic depolarization (AD) is well documented, little is known about the brain states that precede and follow AD onset. Here, by means of multisite extracellular local field potentials and intracellular recordings from identified pyramidal cells, we investigated the laminar expression of cortical activities induced by transient anoxia in rat primary somatosensory cortex. Soon after the interruption of brain oxygenation, we observed a well-organized sequence of stereotyped activity patterns across all cortical layers. This sequence included an initial period of beta-gamma activity, rapidly replaced by delta-theta oscillations followed by a decline in all spontaneous activites, marking the entry into a sustained period of electrical silence. Intracellular recordings revealed that cortical pyramidal neurons were depolarized and highly active during high-frequency activity, became inactive and devoid of synaptic potentials during the isoelectric state, and showed subthreshold composite synaptic depolarizations during the low-frequency period. Contrasting with the strong temporal coherence of pre-AD activities along the vertical axis of the cortical column, the onset of AD was not uniform across layers. AD initially occurred in layer 5 or 6 and then propagated bidirectionally in the upward and downward direction. Conversely, the post-anoxic waves that indicated the repolarization of cortical neurons upon brain reoxygenation did not exhibit a specific spatio-temporal profile. Pyramidal neurons from AD initiation site had a more depolarized resting potential and higher spontaneous firing rate compared to superficial cortical cells. We also found that the propagation pattern of AD was reliably reproduced by focal injection of an inhibitor of sodium­potassium ATPases, suggesting that cortical AD dynamics could reflect layer-dependent variations in cellular metabolic regulations.


Assuntos
Neocórtex , Animais , Ratos , Neurônios , Células Piramidais , Ciclo Celular , Hipóxia
7.
Leukemia ; 37(6): 1245-1253, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37085611

RESUMO

Tandem duplications (TDs) of the UBTF gene have been recently described as a recurrent alteration in pediatric acute myeloid leukemia (AML). Here, by screening 1946 newly diagnosed adult AML, we found that UBTF-TDs occur in about 3% of patients aged 18-60 years, in a mutually exclusive pattern with other known AML subtype-defining alterations. The characteristics of 59 adults with UBTF-TD AML included young age (median 37 years), low bone marrow (BM) blast infiltration (median 25%), and high rates of WT1 mutations (61%), FLT3-ITDs (51%) and trisomy 8 (29%). BM morphology frequently demonstrates dysmyelopoiesis albeit modulated by the co-occurrence of FLT3-ITD. UBTF-TD patients have lower complete remission (CR) rates (57% after 1 course and 76% after 2 courses of intensive chemotherapy [ICT]) than UBTF-wild-type patients. In patients enrolled in the ALFA-0702 study (n = 614 patients including 21 with UBTF-TD AML), the 3-year disease-free survival (DFS) and overall survival of UBTF-TD patients were 42.9% (95%CI: 23.4-78.5%) and 57.1% (95%CI: 39.5-82.8%) and did not significantly differ from those of ELN 2022 intermediate/adverse risk patients. Finally, the study of paired diagnosis and relapsed/refractory AML samples suggests that WT1-mutated clones are frequently selected under ICT. This study supports the recognition of UBTF-TD AML as a new AML entity in adults.


Assuntos
Leucemia Mieloide Aguda , Adulto , Criança , Humanos , Intervalo Livre de Doença , Tirosina Quinase 3 Semelhante a fms/genética , Leucemia Mieloide Aguda/genética , Mutação , Prognóstico , Indução de Remissão
8.
Haematologica ; 108(9): 2369-2379, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36951151

RESUMO

Debates on the role and timing of allogeneic hemtopoietic stem cell transplantation (HSCT) in acute myelogenous leukemia (AML) have persisted for decades. Time to transplant introduces an immortal time and current treatment algorithm mainly relies on the European LeukemiaNet disease risk classification. Previous studies are also limited to age groups, remission status and other ill-defined parameters. We studied all patients at diagnosis irrespective of age and comorbidities to estimate the cumulative incidence and potential benefit or disadvantage of HSCT in a single center. As a time-dependent covariate, HSCT improved overall survival in intermediate- and poor-risk patients (hazard ratio =0.51; P=0.004). In goodrisk patients only eight were transplanted in first complete remission. Overall, the 4-year cumulative incidence of HSCT was only 21.9% but was higher (52.1%) for patients in the first age quartile (16-57 years old) and 26.4% in older patients (57-70 years old) (P<0.001). It was negligible in patients older than 70 years reflecting our own transplant policy but also barriers to transplantation (comorbidities and remission status). However, HSCT patients need to survive, be considered eligible both by the referring and the HSCT physicians and have a suitable donor to get transplantation. We, thus, comprehensively analyzed the complete decision-making and outcome of all our AML patients from diagnosis to last followup to decipher how patient allocation and therapy inform the value of HSCT. The role of HSCT in AML is shifting with broad access to different donors including haploidentical ones. Thus, it may (or may not) lead to increased numbers of allogeneic HSCT in AML in adults.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Adulto , Humanos , Idoso , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Transplante Homólogo , Leucemia Mieloide Aguda/terapia , Indução de Remissão , Modelos de Riscos Proporcionais , Estudos Retrospectivos
9.
BMC Cancer ; 22(1): 972, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36088307

RESUMO

BACKGROUND: Myelodysplastic syndromes (MDS) are clonal hematopoietic diseases of the elderly characterized by chronic cytopenias, ineffective and dysplastic haematopoiesis, recurrent genetic abnormalities and increased risk of progression to acute myeloid leukemia. A challenge of routine laboratory Complete Blood Counts (CBC) is to correctly identify MDS patients while simultaneously avoiding excess smear reviews. To optimize smear review, the latest generations of hematology analyzers provide new cell population data (CPD) parameters with an increased ability to screen MDS, among which the previously described MDS-CBC Score, based on Absolute Neutrophil Count (ANC), structural neutrophil dispersion (Ne-WX) and mean corpuscular volume (MCV). Ne-WX is increased in the presence of hypogranulated/degranulated neutrophils, a hallmark of dysplasia in the context of MDS or chronic myelomonocytic leukemia. Ne-WX and MCV are CPD derived from leukocytes and red blood cells, therefore the MDS-CBC score does not include any platelet-derived CPD. We asked whether this score could be improved by adding the immature platelet fraction (IPF), a CPD used as a surrogate marker of dysplastic thrombopoiesis. METHODS: Here, we studied a cohort of more than 500 individuals with cytopenias, including 168 MDS patients. In a first step, we used Breiman's random forests algorithm, a machine-learning approach, to identify the most relevant parameters for MDS prediction. We then designed Classification And Regression Trees (CART) to evaluate, using resampling, the effect of model tuning parameters on performance and choose the "optimal" model across these parameters. RESULTS: Using random forests algorithm, we identified Ne-WX and IPF as the strongest discriminatory predictors, explaining 37 and 33% of diagnoses respectively. To obtain "simplified" trees, which could be easily implemented into laboratory middlewares, we designed CART combining MDS-CBC score and IPF. Optimal results were obtained using a MDS-CBC score threshold equal to 0.23, and an IPF threshold equal to 3%. CONCLUSIONS: We propose an extended MDS-CBC score, including CPD from the three myeloid lineages, to improve MDS diagnosis on routine laboratory CBCs and optimize smear reviews.


Assuntos
Anemia , Hematologia , Síndromes Mielodisplásicas , Trombocitopenia , Idoso , Contagem de Células Sanguíneas , Plaquetas , Humanos , Aprendizado de Máquina , Síndromes Mielodisplásicas/diagnóstico
10.
ACS Appl Mater Interfaces ; 14(18): 20835-20847, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35481776

RESUMO

Li-ion batteries are the electrochemical energy storage technology of choice of today's electrical vehicles and grid applications with a growing interest for Na-ion and K-ion systems based on either aqueous or non-aqueous electrolyte for power, cost, and sustainable reasons. The rate capability of alkali-metal-ion batteries is influenced by ion transport properties in the bulk of the electrolyte, as well as by diverse effects occurring at the vicinity of the electrode and electrolyte interface. Therefore, identification of the predominant factor affecting the rate capability of electrodes still remains a challenge and requires suitable experimental and computational methods. Herein, we investigate the mechanistic of the K+ insertion process in the Prussian blue phase, Fe4III[FeII(CN)6]3 in both aqueous and non-aqueous electrolytes, which reveals drastic differences. Through combined electrochemical characterizations, electrochemical-quartz-crystal-microbalance and ac-electrogravimetric analyses, we provide evidences that what matters the most for fast ion transport is the positioning of the partially solvated cations adsorbed at the material surface in aqueous as opposed to non-aqueous electrolytes. We rationalized such findings by molecular dynamics simulations that establish the K+ repartition profile within the electrochemical double layer. A similar trend was earlier reported by our group for the aqueous versus non-aqueous insertion of Li+ into LiFePO4. Such a study unveils the critical but overlooked role of the electrode-electrolyte interface in ruling ion transport and insertion processes. Tailoring this interface structuring via the proper salt-solvent interaction is the key to enabling the best power performances in alkali-metal-ion batteries.

12.
JAMA Dermatol ; 157(11): 1349-1354, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34495287

RESUMO

IMPORTANCE: VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) is a recently described severe adult-onset autoinflammatory disease that is associated with myeloid lineage-restricted ubiquitin-activating enzyme 1 (UBA1) somatic variations that primarily affect the skin (Sweet syndrome), cartilage, and bone marrow. Skin symptoms have been poorly described. OBJECTIVE: To better describe clinical and pathological skin manifestations and their pathophysiology in VEXAS syndrome. DESIGN, SETTING, AND PARTICIPANTS: This multicenter retrospective case series study of clinical and histological features of 8 patients with VEXAS syndrome and skin involvement was conducted in France from December 2007 to March 2021, with molecular data obtained from March to April 2022. Any UBA1 variations were detected by Sanger or next-generation sequencing that was performed on bone marrow and formalin-fixed paraffin-embedded tissue sections of skin lesion biopsies. RESULTS: All 8 patients were men, and the median age at symptom onset was 65.5 years (interquartile range, 54-76 years). All patients had neutrophilic dermatosis skin lesions, including tender red or violaceous papules, sometimes edematous, without fever, arthralgia, recurrence or pathergy, inflammatory edematous papules on the neck and trunk (sometimes umbilicated), and firm erythematous purpuric or pigmented infiltrated plaques and nodules. Three patients had livedo racemosa. The infiltrates were perivascular and consisted of mature neutrophils with leukocytoclasia, which were admixed with myeloperoxidase-positive CD163-positive myeloid cells with indented nuclei and lymphoid cells in all cases. A sequencing analysis of paired bone marrow samples and skin lesion biopsies identified the same loss-of-function UBA1 variation in both samples for all patients. CONCLUSIONS AND RELEVANCE: This case series study describes the different clinical presentations of skin lesions found in VEXAS syndrome, which is characterized histologically by neutrophilic dermatosis. The findings suggested that the dermal infiltrates seen in VEXAS skin lesions are derived from the pathological myeloid clone. This suggests that using therapies that target the pathological clone may be effective in the long-term management of the disease.


Assuntos
Síndrome de Sweet , Enzimas Ativadoras de Ubiquitina , Adulto , Medula Óssea , Humanos , Masculino , Mutação , Estudos Retrospectivos , Síndrome de Sweet/diagnóstico , Enzimas Ativadoras de Ubiquitina/genética
15.
Sensors (Basel) ; 21(2)2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33450881

RESUMO

Unmanned aerial vehicles (UAVs) have become a very popular way of acquiring video within contexts such as remote data acquisition or surveillance. Unfortunately, their viewpoint is often unstable, which tends to impact the automatic processing of their video flux negatively. To counteract the effects of an inconsistent viewpoint, two video processing strategies are classically adopted, namely registration and stabilization, which tend to be affected by distinct issues, namely jitter and drifting. Following our prior work, we suggest that the motion estimators used in both situations can be modeled to take into account their inherent errors. By acknowledging that drifting and jittery errors are of a different nature, we propose a combination that is able to limit their influence and build a hybrid solution for jitter-free video registration. In this work, however, our modeling was restricted to 2D-rigid transforms, which are rather limited in the case of airborne videos. In the present paper, we extend and refine the theoretical ground of our previous work. This addition allows us to show how to practically adapt our previous work to perspective transforms, which our study shows to be much more accurate for this problem. A lightweight implementation enables us to automatically register stationary UAV videos in real time. Our evaluation includes traffic surveillance recordings of up to 2 h and shows the potential of the proposed approach when paired with background subtraction tasks.

16.
Br J Haematol ; 193(1): 72-82, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33314017

RESUMO

A translocation involving the cyclin-dependent kinase 6 (CDK6) gene [t(CDK6)] is a rare but recurrent abnormality in B-cell neoplasms. To further characterise this aberration, we studied 57 cases; the largest series reported to date. Fluorescence in situ hybridisation analysis confirmed the involvement of CDK6 in all cases, including t(2;7)(p11;q21) immunoglobulin kappa locus (IGK)/CDK6 (n = 51), t(7;14)(q21;q32) CDK6/immunoglobulin heavy locus (IGH) (n = 2) and the previously undescribed t(7;14)(q21;q11) CDK6/T-cell receptor alpha locus (TRA)/T-cell receptor delta locus (TRD) (n = 4). In total, 10 patients were diagnosed with chronic lymphocytic leukaemia, monoclonal B-cell lymphocytosis or small lymphocytic lymphoma, and 47 had small B-cell lymphoma (SmBL) including 36 cases of marginal zone lymphoma (MZL; 34 splenic MZLs, one nodal MZL and one bronchus-associated lymphoid tissue lymphoma). In all, 18 of the 26 cytologically reviewed cases of MZL (69%) had an atypical aspect with prolymphocytic cells. Among the 47 patients with MZL/SmBL, CD5 expression was found in 26 (55%) and the tumour protein p53 (TP53) deletion in 22 (47%). The TP53 gene was mutated in 10/30 (33%); the 7q deletion was detected in only one case, and no Notch receptor 2 (NOTCH2) mutations were found. Immunoglobulin heavy-chain variable-region (IGHV) locus sequencing revealed that none harboured an IGHV1-02*04 gene. Overall survival was 82% at 10 years and not influenced by TP53 aberration. Our present findings suggest that most t(CDK6)+ neoplasms correspond to a particular subgroup of indolent marginal zone B-cell lymphomas with distinctive features.


Assuntos
Antígenos CD5/metabolismo , Quinase 6 Dependente de Ciclina/metabolismo , Leucemia Linfocítica Crônica de Células B/metabolismo , Linfoma de Zona Marginal Tipo Células B/metabolismo , Neoplasias Esplênicas/patologia , Proteína Supressora de Tumor p53/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Brônquicas/diagnóstico , Neoplasias Brônquicas/metabolismo , Diferenciação Celular , Aberrações Cromossômicas , Feminino , Genes p53/genética , Humanos , Cadeias Pesadas de Imunoglobulinas/metabolismo , Hibridização in Situ Fluorescente/métodos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Linfoma de Zona Marginal Tipo Células B/diagnóstico , Linfoma de Zona Marginal Tipo Células B/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Mutação , Fenótipo , Análise de Sobrevida , Estruturas Linfoides Terciárias/patologia , Translocação Genética/genética , Trissomia/genética
17.
Sci Rep ; 10(1): 18468, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33116241

RESUMO

The development of microarray patches for vaccine application has the potential to revolutionise vaccine delivery. Microarray patches (MAP) reduce risks of needle stick injury, do not require reconstitution and have the potential to enhance immune responses using a fractional vaccine dose. To date, the majority of research has focused on vaccine delivery with little characterisation of local skin response and recovery. Here we study in detail the immediate local skin response and recovery of the skin post high density MAP application in 12 individuals receiving 3 MAPs randomly assigned to the forearm and upper arm. Responses were characterised by clinical scoring, dermatoscopy, evaporimetry and tissue viability imaging (TiVi). MAP application resulted in punctures in the epidermis, a significant transepidermal water loss (TEWL), the peak TEWL being concomitant with peak erythema responses visualised by TiVi. TEWL and TiVi responses reduced over time, with TEWL returning to baseline by 48 h and erythema fading over the course of a 7 day period. As MAPs for vaccination move into larger clinical studies more variation of individual subject phenotypic or disease propensity will be encountered which will require consideration both in regard to reliability of dose delivery and degree of inherent skin response.


Assuntos
Epiderme , Eritema , Adesivo Transdérmico/efeitos adversos , Vacinação/efeitos adversos , Vacinas , Adolescente , Adulto , Idoso , Epiderme/imunologia , Epiderme/patologia , Eritema/etiologia , Eritema/imunologia , Eritema/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Vacinas/administração & dosagem , Vacinas/imunologia
18.
Anal Chem ; 92(20): 13803-13812, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32945170

RESUMO

Numerous sophisticated diagnostic techniques have been designed to monitor electrode-electrolyte interfaces that mainly govern the lifetime and reliability of batteries. Among them is the electrochemical quartz crystal microbalance (EQCM) that offers valuable insights of the interfaces once the required conditions of the deposited film in terms of viscoelastic and hydrodynamic properties are fulfilled. Herein, we propose a friendly protocol that includes the elaboration of a homogeneous deposit by spray coating followed by QCM measurements at multiharmonic frequencies to ensure the film flatness and rigidity for collecting meaningful data. Moreover, for easiness of the measurements, we report the design of a versatile and airtight EQCM cell setup that can be used either with aqueous or non-aqueous electrolytes. We also present, using a model battery material, LiFePO4, how dual frequency and motional resistance monitoring during electrochemical cycling can be used as a well-suitable indicator for achieving reliable and reproducible electrogravimetric measurements. We demonstrate through this study the essential role of the solvent assisting lithium-ion insertion at the LiFePO4 interface with a major outcome of solvent-dependent interfacial behavior. Namely, in aqueous media, we prove a near-surface desolvation of lithium ions from their water solvation shell as compared with organic molecules. This spatial dissimilarity leads to a smoother Li-ion transport across the LFP-H2O interface, hence accounting for the difference in rate capability of LFP in the respective electrolytes. Overall, we hope our analytical insights on interfacial mechanisms will help in gaining a wider acceptance of EQCM-based methods from the battery community.

19.
Front Pediatr ; 8: 304, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32596193

RESUMO

Background: In patients with pituitary stalk interruption syndrome (PSIS), long-term follow-up is necessary to address their gonadotrophic status. The objectives of this study were (1) to describe pubertal features of and (2) to assess the ability of serum inhibin B concentration to predict hypogonadotropic hypogonadism (HH) in patients with PSIS. Methods: This retrospective single-center study included 35 patients with PSIS and known gonadotrophic status for whom a serum sample preserved at -22°C (collected at initial evaluation or later) was available for measuring inhibin B by the same hormonal immunoassay method. Results: Among the 21 boys, 15 had normal puberty (early in two), and six had partial (n = 2) or complete (n = 4) HH. Among the 14 girls, five had normal puberty (early in one)-four with regular menses and one in the process of puberty-, four had complete HH, and five had amenorrhea (primary in three and secondary in two) after normal pubertal development, despite a normal pubertal gonadotropin response to gonadotropin-releasing hormone test. These were considered as having partial HH. Only three boys had values over the normal lower range for serum inhibin B concentrations despite partial (n = 2) or complete (n = 1) HH. Inhibin B concentrations were low in all girls with complete HH, normal in all those with partial HH except in one and in those with normal puberty except in two. Considering boys and girls together, the occurrence of under-range inhibin B was significantly higher in those with HH than in those without (47 vs. 10%, p = 0.02). All 15 patients with HH had associated thyroid-stimulating hormone and adrenocorticotropic hormone deficiency except for 3 girls with partial HH. Conclusions: Under-range inhibin B concentrations in patients with PSIS might be suggestive of HH. These concentrations provide a simple first-line predictive test, especially in boys.

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