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1.
Small ; : e2403028, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38860552

ABSTRACT

Methane is a valuable resource and its valorization is an important challenge in heterogeneous catalysis. Here it is shown that CeO2/CuO composite prepared by ball milling activates methane at a temperature as low as 250 °C. In contrast to conventionally prepared catalysts, the formation of partial oxidation products such as methanol and formaldehyde is also observed. Through an in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) and operando Near Edge X-Ray Absorption Fine Structure Spectroscopy (NEXAFS) approach, it can be established that this unusual reactivity can be attributed to the presence of Ce4+/Cu+ interfaces generated through a redox exchange between Ce3+ and Cu2+ atoms facilitated by the mechanical energy supplied during milling. DFT modeling of the electronic properties confirms the existence of a charge transfer mechanism. These results demonstrate the effectiveness and distinctiveness of the mechanical approach in creating unique and resilient interfaces thereby enabling the optimization and refining of CeO2/CuO catalysts in methane activation reactions.

3.
JCEM Case Rep ; 2(1): luad153, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38170043

ABSTRACT

Glucocorticoid resistance syndrome is a rare genetic condition characterized by generalized or partial target-tissue insensitivity to glucocorticoids and a consequent hyperactivation of the hypothalamic-pituitary-adrenal axis. Clinical manifestations may include mineralocorticoid and/or androgen excess without manifestations of Cushing syndrome. At a cellular level, glucocorticoid actions are mediated by the nuclear glucocorticoid receptor encoded by the NR3C1 gene. To date, only 33 glucocorticoid receptor loss-of-function pathogenic variants have been associated with glucocorticoid resistance syndrome. The NR3C1 gene has 2 known disease-causing mechanisms: haploinsufficiency and negative dominance. We describe a mother and her son with a mild hyperandrogenic phenotype and a novel genetic variant of the NR3C1 gene predicting a truncated protein and causing glucocorticoid resistance syndrome. To date, no accurate genotype-phenotype correlation has been found.

5.
Nat Commun ; 14(1): 7280, 2023 Nov 10.
Article in English | MEDLINE | ID: mdl-37949914

ABSTRACT

The combination of the ability to absorb most of the solar radiation and simultaneously suppress infrared re-radiation allows selective solar absorbers (SSAs) to maximize solar energy to heat conversion, which is critical to several advanced applications. The intrinsic spectral selective materials are rare in nature and only a few demonstrated complete solar absorption. Typically, intrinsic materials exhibit high performances when integrated into complex multilayered solar absorber systems due to their limited spectral selectivity and solar absorption. In this study, we propose CoSbx (2 < x < 3) as a new exceptionally efficient SSA. Here we demonstrate that the low bandgap nature of CoSbx endows broadband solar absorption (0.96) over the solar spectral range and simultaneous low emissivity (0.18) in the mid-infrared region, resulting in a remarkable intrinsic spectral solar selectivity of 5.3. Under 1 sun illumination, the heat concentrates on the surface of the CoSbx thin film, and an impressive temperature of 101.7 °C is reached, demonstrating the highest value among reported intrinsic SSAs. Furthermore, the CoSbx was tested for solar water evaporation achieving an evaporation rate of 1.4 kg m-2 h-1. This study could expand the use of narrow bandgap semiconductors as efficient intrinsic SSAs with high surface temperatures in solar applications.

6.
Article in English | MEDLINE | ID: mdl-37870421

ABSTRACT

Concomitant presence of atrial fibrillation and coronary artery disease requiring percutaneous coronary intervention is a frequent occurrence. The choice of optimal antithrombotic therapy, in this context, is still challenging. To offer the best protection both in terms of stroke and stent thrombosis, triple therapy with oral anticoagulation and dual antiplatelet therapy would be required. Several drug combinations have been tested in recent years, including direct oral anticoagulants, with the aim of balancing ischemic and bleeding risk. Both pharmacokinetic aspects of the molecules and patient's characteristics should be analyzed in choosing oral anticoagulation. Then, as suggested by guidelines, triple therapy should start with a seven-day duration and the aim to prolong to thirty days in high thrombotic risk patients. Dual therapy should follow to reach twelve months after coronary intervention. Even not fully discussed by the guidelines, in order to balance ischemic and bleeding risk it should also be considered: 1) integrated assessment of coronary artery disease and procedural complexity of coronary intervention; 2) appropriateness to maintain the anticoagulant drug dosage indicated in technical data sheet; the lack of data on the suspension of antiplatelet drugs one year after percutaneous intervention; 3) the possibility of combination therapy with ticagrelor; and 4) the need to treat the occurrence of paroxysmal atrial fibrillation during acute coronary syndrome. With data provided clinician should pursue a therapy as personalized as possible, both in terms of drug choice and treatment duration, in order to balance ischemic and bleeding risk.

7.
ACS Appl Mater Interfaces ; 15(21): 26166-26174, 2023 May 31.
Article in English | MEDLINE | ID: mdl-37199730

ABSTRACT

Magnesium chloride is a prototypical deliquescent material whose surface properties, although central for Ziegler-Natta cataysis, have so far remained elusive to experimental characterization. In this work, we use surface-selective X-ray absorption spectroscopy (XAS) at ambient pressure in combination with multivariate curve resolution, molecular dynamics, and XAS theoretical methods to track in real time and accurately describe the interaction between water vapor and the MgCl2 surface. By exposing MgCl2 to water vapor at temperatures between 595 and 391 K, we show that water is preferentially adsorbed on five-coordinated Mg2+ sites in an octahedral configuration, confirming previous theoretical predictions, and find that MgCl2 is capable of retaining a significant amount of adsorbed water even under prolonged heating to 595 K. As a consequence, our work provides first experimental insights into the unique surface affinity of MgCl2 for atmospheric water. The developed technique is proven highly sensitive to the modifications induced by adsorbates on a given low-Z metal based surface and may be useful in the toolbox required to disentangle the mechanisms of interfacial chemical processes.

8.
J Phys Chem Lett ; 14(5): 1334-1342, 2023 Feb 09.
Article in English | MEDLINE | ID: mdl-36727689

ABSTRACT

Hydrogen production from methanol decomposition to syngas (H2 + CO) is a promising alternative route for clean energy transition. One major challenge is related to the quest for stable, cost-effective, and selective catalysts operating below 400 °C. We illustrate an investigation of the surface reactivity of a Ni3Sn4 catalyst working at 250 °C, by combining density functional theory, operando X-ray absorption spectroscopy, and high-resolution transmission electron microscopy. We discovered that the catalytic reaction is driven by surface tin-oxide phases, which protects the underlying Ni atoms from irreversible chemical modifications, increasing the catalyst durability. Moreover, we found that Sn content plays a key role in enhancing the H2 selectivity, with respect to secondary products such as CO2. These findings open new perspectives for the engineering of scalable and low-cost catalysts for hydrogen production.

9.
Nanomaterials (Basel) ; 13(2)2023 Jan 09.
Article in English | MEDLINE | ID: mdl-36678025

ABSTRACT

The development of Ce-based materials is directly dependent on the catalyst surface defects, which is caused by the calcination steps required to increase structural stability. At the same time, the evaluation of cerium's redox properties under reaction conditions is of increasing relevant importance. The synthesis of Ce-UiO-66 and CeZr-UiO-66 and their subsequent calcination are presented here as a simple and inexpensive approach for achieving homogeneous and stable CeO2 and CeZrOx nanocrystals. The resulting materials constitute an ideal case study to thoroughly understand cerium redox properties. The Ce3+/Ce4+ redox properties are investigated by H2-TPR experiments exploited by in situ FT-IR and Ce M5-edge AP-NEXAFS spectroscopy. In the latter case, Ce3+ formation is quantified using the MCR-ALS protocol. FT-IR is then presented as a high potential/easily accessible technique for extracting valuable information about the cerium oxidation state under operating conditions. The dependence of the OH stretching vibration frequency on temperature and Ce reduction is described, providing a novel tool for qualitative monitoring of surface oxygen vacancy formation. Based on the reported results, the molecular absorption coefficient of the Ce3+ characteristic IR transition is tentatively evaluated, thus providing a basis for future Ce3+ quantification through FT-IR spectroscopy. Finally, the FT-IR limitations for Ce3+ quantification are discussed.

10.
ACS Appl Mater Interfaces ; 14(33): 38370-38378, 2022 Aug 24.
Article in English | MEDLINE | ID: mdl-35968677

ABSTRACT

Interfaces between water and materials are ubiquitous and are crucial in materials sciences and in biology, where investigating the interaction of water with the surface under ambient conditions is key to shedding light on the main processes occurring at the interface. Magnesium oxide is a popular model system to study the metal oxide-water interface, where, for sufficient water loadings, theoretical models have suggested that reconstructed surfaces involving hydrated Mg2+ metal ions may be energetically favored. In this work, by combining experimental and theoretical surface-selective ambient pressure X-ray absorption spectroscopy with multivariate curve resolution and molecular dynamics, we evidence in real time the occurrence of Mg2+ solvation at the interphase between MgO and solvating media such as water and methanol (MeOH). Further, we show that the Mg2+ surface ions undergo a reversible solvation process, we prove the dissolution/redeposition of the Mg2+ ions belonging to the MgO surface, and we demonstrate the formation of octahedral [Mg(H2O)6]2+ and [Mg(MeOH)6]2+ intermediate solvated species. The unique surface, electronic, and structural sensitivity of the developed technique may be beneficial to access often elusive properties of low-Z metal ion intermediates involved in interfacial processes of chemical and biological interest.

11.
Nanomaterials (Basel) ; 12(9)2022 May 09.
Article in English | MEDLINE | ID: mdl-35564319

ABSTRACT

The electronic properties of 2D boroxine networks are computationally investigated by simulating the NEXAFS spectra of a series of molecular models, with or without morphologic defects, with respect to the ideal honeycomb structure. The models represent portions of an irregular 2D boroxine framework obtained experimentally, as supported by the Au(111) surface. The B K-edge NEXAFS spectra are calculated within the transition potential (TP) approximation (DFT-TP). The role of the Au(111) supporting surface on the spectral features has also been investigated by comparing the calculated spectra of a defect-rich model in its free-standing and supported form. The calculated NEXAFS spectra differ from the experimental ones, as the position of the main resonance does not match in the two cases. This finding could suggest the presence of a strong interaction of the 2D boroxine network with the Au substrate, which is not captured in the model calculations. However, good agreement between measured and calculated B K-edge NEXAFS spectra is obtained for a model system, namely, trihydroxy boroxine, in which the B atoms are less screened by the valence electrons compared to the B-B linked boroxine network models considered here. These results suggest catalytic activity in the gold substrate in promoting a weakening or even the breaking of the B-B bond, which is not revealed by calculations.

12.
J Endocr Soc ; 6(5): bvac028, 2022 May 01.
Article in English | MEDLINE | ID: mdl-35350393

ABSTRACT

Context: Small-for-gestational-age (SGA) children have a particular metabolic and hormonal pattern at birth that changes rapidly. Objective: To evaluate the linear and weight growth in the first year of life in SGA children. Design: Prospective, monocentric cohort study. Setting: Real-world data collected from April 2012 to January 2016. Patients: SGA newborns uniformly defined by either growth or length lower than -2 SDs for gestational age. Interventions: All children were evaluated for 1 year after birth, at 3 days of life, then 3, 6, and 12 months after birth. Main outcome measures: Anthropometric parameters and biochemical variables, such as blood glucose, insulin, leptin, IGF-1, IGF binding protein-3 (IGFBP-3), and homeostasis model assessment - insulin resistance (HOMA-IR) index. Results: A total of 133 SGA children were enrolled. Length significantly improved 1 month after birth, whereas weight significantly increased only at 3 months after birth. Biochemical variables increased during the first year of life, showing a prediction by IGFBP-3 and HOMA-IR index. Then, the variables were divided considering either weight, length, or both, showing a different incidence. The biochemical variable changes recorded in the first step were maintained considering SGA children for weight or length, whereas they disappeared when weight and length were considered together. Conclusions: Our study shows a specific catchup growth for weight and length in SGA children. Moreover, we highlight that weight and length should be considered as independent parameters in SGA children, defining 2 different metabolic-hormonal populations with different conceivable predictive role in early catchup growth and in later growth and metabolic status.

13.
ACS Appl Energy Mater ; 5(2): 1905-1913, 2022 Feb 28.
Article in English | MEDLINE | ID: mdl-35252774

ABSTRACT

Lithium-rich layered oxides (LRLOs) are opening unexplored frontiers for high-capacity/high-voltage positive electrodes in Li-ion batteries (LIBs) to meet the challenges of green and safe transportation as well as cheap and sustainable stationary energy storage from renewable sources. LRLOs exploit the extra lithiation provided by the Li1.2TM0.8O2 stoichiometries (TM = a blend of transition metals with a moderate cobalt content) achievable by a layered structure to disclose specific capacities beyond 200-250 mA h g-1 and working potentials in the 3.4-3.8 V range versus Li. Here, we demonstrate an innovative paradigm to extend the LRLO concept. We have balanced the substitution of cobalt in the transition-metal layer of the lattice with aluminum and lithium, pushing the composition of LRLO to unexplored stoichiometries, that is, Li1.2+x (Mn,Ni,Co,Al)0.8-x O2-δ. The fine tuning of the composition of the metal blend results in an optimized layered material, that is, Li1.28Mn0.54Ni0.13Co0.02Al0.03O2-δ, with outstanding electrochemical performance in full LIBs, improved environmental benignity, and reduced manufacturing costs compared to the state-of-the-art.

14.
J Phys Chem Lett ; 12(37): 9182-9187, 2021 Sep 23.
Article in English | MEDLINE | ID: mdl-34528795

ABSTRACT

In this work, we apply for the first time ambient pressure operando soft X-ray absorption spectroscopy (XAS) to investigate the location, structural properties, and reactivity of the defective sites present in the prototypical metal-organic framework HKUST-1. We obtained direct evidence that Cu+ defective sites form upon temperature treatment of the powdered form of HKUST-1 at 160 °C and that they are largely distributed on the material surface. Further, a thorough structural characterization of the Cu+/Cu2+ dimeric complexes arising from the temperature-induced dehydration/decarboxylation of the pristine Cu2+/Cu2+ paddlewheel units is reported. In addition to characterizing the surface defects, we demonstrate that CO2 may be reversibly adsorbed and desorbed from the surface defective Cu+/Cu2+ sites. These findings show that ambient pressure soft-XAS, combined with state-of-the-art theoretical calculations, allowed us to shed light on the mechanism involving the decarboxylation of the paddlewheel units on the surface to yield Cu+/Cu2+ complexes and their reversible restoration upon exposure to gaseous CO2.

17.
Heart Rhythm ; 17(11): 1897-1903, 2020 11.
Article in English | MEDLINE | ID: mdl-32512176

ABSTRACT

BACKGROUND: Recent studies suggest that atrioventricular (AV) conduction may recover after pacemaker (PM) implantation following transcatheter aortic valve replacement (TAVR), but little is known about long-term follow-up of such patients. OBJECTIVE: The purpose of this study was to evaluate the long-term percentage of right ventricular pacing in patients who underwent TAVR and required PM implantation stratified based on the indication for permanent pacing. METHODS: Retrospective analysis of all consecutive patients who underwent TAVR from February 2008 to August 2019 at 3 centers was performed. Patients already implanted with a PM/implantable cardioverter-defibrillator (ICD) before TAVR, implanted with a cardiac resynchronization therapy device, or implanted >30 days after TAVR were excluded. Eligible patients were divided into 2 groups based on the presence (persistent atrioventricular block [AVB] group) or absence (nonpersistent AVB group) of persistent third-degree AVB after TAVR. RESULTS: A total of 1594 patients underwent TAVR. Two hundred four patients were implanted with a PM or ICD after TAVR and 32 met exclusion criteria, so 172 patients were eligible (median time TAVR-PM implant 4 days) for a total of 352 follow-up visits analyzed. A significant difference in the percentage of ventricular pacing was observed at follow-up performed 7-90 days after implantation (98% persistent AVB group vs 8% nonpersistent AVB group; P <.001). This difference remained significant at follow-up performed 91-270 days (95% vs 3.5%; P <.001), 271-540 days (95.5% vs 3%; P = .006), and 541-900 days (97.4% vs 2.2%; P <.001) after implantation. CONCLUSION: Patients requiring PM implantation due to persistent third-degree AVB after TAVR were less likely to show AV conduction recovery, whereas patients implanted for other indications showed a low percentage of pacing during follow-up.


Subject(s)
Aortic Valve/surgery , Atrioventricular Block/therapy , Cardiac Pacing, Artificial/methods , Heart Conduction System/physiopathology , Heart Valve Diseases/surgery , Postoperative Complications , Transcatheter Aortic Valve Replacement/adverse effects , Aged, 80 and over , Atrioventricular Block/etiology , Atrioventricular Block/physiopathology , Female , Follow-Up Studies , Heart Ventricles/physiopathology , Humans , Male , Retrospective Studies , Risk Factors , Time Factors
18.
Ann Vasc Surg ; 60: 480.e1-480.e5, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31200060

ABSTRACT

The prevalence of combined severe aortic stenosis and abdominal aortic aneurysm is increasing with the aging of the population. Both conditions are associated with adverse outcome if not adequately managed. The choice of the optimal treatment of these patients is challenging and no clear recommendations are available. We report 2 cases of patients with concomitant severe symptomatic aortic stenosis and infrarenal abdominal aortic aneurysm successfully treated with combined transfemoral transcatheter aortic valve implantation (TAVI) and endovascular aortic aneurysm repair (EVAR). The reported cases demonstrate the versatility of transcatheter techniques and suggest that, in carefully selected patients, the combined procedure of TAVI plus EVAR, if performed by multidisciplinary expert operators, is safe and effective.


Subject(s)
Aortic Aneurysm, Abdominal/surgery , Aortic Valve Stenosis/surgery , Blood Vessel Prosthesis Implantation , Endovascular Procedures , Transcatheter Aortic Valve Replacement , Aged , Aged, 80 and over , Aortic Aneurysm, Abdominal/complications , Aortic Aneurysm, Abdominal/diagnostic imaging , Aortic Aneurysm, Abdominal/physiopathology , Aortic Valve Stenosis/complications , Aortic Valve Stenosis/diagnostic imaging , Aortic Valve Stenosis/physiopathology , Blood Vessel Prosthesis , Blood Vessel Prosthesis Implantation/instrumentation , Endovascular Procedures/adverse effects , Endovascular Procedures/instrumentation , Female , Heart Valve Prosthesis , Humans , Male , Risk Assessment , Risk Factors , Severity of Illness Index , Stents , Transcatheter Aortic Valve Replacement/adverse effects , Transcatheter Aortic Valve Replacement/instrumentation , Treatment Outcome
19.
Int J Cardiol ; 280: 46-48, 2019 04 01.
Article in English | MEDLINE | ID: mdl-30700383

ABSTRACT

Current guidelines recommend a three- to six-months dual antiplatelet therapy (DAPT) in patients undergoing transcatheter aortic valve replacement (TAVR) or to continue with oral anticoagulant agents (OAC) if already indicated before procedure. However, recent studies showed that treatment with aspirin has the same efficacy of DAPT but it was associated with a significant reduction of major bleeding. Furthermore, half of cerebrovascular events, occurring >24 h after procedure, may be related to new onset of atrial fibrillation or to subclinical leaflets thrombosis and they may be prevented by use of OAC rather than antiplatelet therapy. In absence of very high bleeding risk and of recent percutaneous coronary intervention, the use of OAC over SAPT or DAPT might theoretically be considered in patients undergoing TAVR waiting for results of ongoing clinical trials.


Subject(s)
Anticoagulants/administration & dosage , Aortic Valve Stenosis/surgery , Platelet Aggregation Inhibitors/administration & dosage , Transcatheter Aortic Valve Replacement/trends , Atrial Fibrillation/etiology , Atrial Fibrillation/prevention & control , Humans , Thrombosis/etiology , Thrombosis/prevention & control , Transcatheter Aortic Valve Replacement/adverse effects
20.
Nutr. hosp ; 36(1): 233-237, ene.-feb. 2019. graf
Article in Spanish | IBECS | ID: ibc-183207

ABSTRACT

Objetivo: exponer los resultados del registro de nutrición enteral domiciliaria (NED) de los años 2016 y 2017 del Grupo NADYA-SENPE. Material y métodos: se recopilaron los pacientes introducidos en el registro del 1 de enero al 31 de diciembre de 2016 y la mismas fechas de 2017 para proceder al análisis descriptivo y analítico de los datos. Resultados: en el año 2016 se obtuvieron 4.578 pacientes activos (prevalencia = 98,33 pacientes/millón de habitantes) y en 2017 fueron 4.777 (prevalencia = 102,57). Por sexos, hubo un 50,8% de varones en 2016 y un 50,5% en 2017. En el periodo 2016-17, la edad mediana fue de 71,5 años (IIQ 57-83); asimismo, finalizaron 1.558 episodios de NED y la causa principal fue el fallecimiento (793 pacientes, 50,89%). Los varones adultos fueron más jóvenes que las mujeres (65,3 vs. 73,3 años, p-valor < 0,001) y el diagnóstico más frecuente fue la enfermedad neurológica que cursa con afagia o disfagia severa (59%). La sonda nasogástrica (SNG) fue la vía de acceso más utilizada (48,3%) y se observa, además, que esta es la vía que se utiliza en los pacientes más ancianos (p < 0,001). Se registraron 126 pacientes pediátricos (57,1% niñas). La edad mediana de inicio de la NED fue de cuatro meses. Otras patologías fue el grupo diagnóstico más registrado (41,3%), seguido por la enfermedad neurológica que cursa con afagia o disfagia severa. Se alimentaban a través de gastrostomía en el 57,6% de los casos. Se observó que los niños más pequeños eran los que se alimentaban preferentemente por SNG (p-valor 0,001). Conclusiones: el número de pacientes del registro, así como el número de centros participantes, se va incrementando progresivamente. Las principales características de los pacientes no han variado. A pesar del aumento de posibilidades diagnósticas en la población pediátrica, llama la atención la clasificación dentro del grupo de Otras patologías


Objective: to present the results of the Spanish home enteral nutrition (HEN) registry of the NADYA-SENPE group for the year 2016 and 2017. Material and methods: from January 1st 2016 to December 31st 2017, the HEN registry was recorded and afterwards a further descriptive and analytical analysis was done. Results: in 2016, 4,578 active patients were recorded and prevalence was 98.33 patients per one million inhabitants; in 2017, 4,777 patients were recorded, with a prevalence of 102.57 per one million inhabitants; 50.8% were males in 2016 and 50.5% in 2017. During the period 2016-17, median age was 71.5 years (IIQ 57-83), 1,558 HEN episodes were finished and the main cause was death (793 patients, 50.89%). Adult males were younger than females (65.3 vs. 73.3 years, p-value < 0.001). The most frequent diagnosis was the neurological disorder that presents with aphagia or severe dysphagia (59%). Nasogastric tube was the most frequent administration route (48.3%) and it is the most widely used in elderly patients (p < 0.001). One hundred and twenty-six pediatric patients were registered (57.1% females). Median age at the beginning of HEN in children was four months. "Other disorders" was the most recorded diagnostic group (41.3%), followed by the group of neurological disorder that presents with aphagia or severe dysphagia. Regarding children, 57.6% were fed through gastrostomy and the younger ones were fed through nasogastric tube (p-value 0.001). Conclusions: the number of patients in the registry, as well as the number of participating centers, is progressively increasing. The main characteristics of the patients have not changed. Despite the increase in diagnostic possibilities in the pediatric population, the classification within the group of "Other pathologies" is quite significant


Subject(s)
Humans , Male , Female , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Young Adult , Adult , Middle Aged , Aged , Aged, 80 and over , Enteral Nutrition/statistics & numerical data , Parenteral Nutrition, Home/statistics & numerical data , Records , Enteral Nutrition/trends , Parenteral Nutrition/trends , Parenteral Nutrition, Home/trends , Sex Factors , Spain/epidemiology
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