Germanium is known to occupy tetrahedral sites by substituting silicon in germanosilicate zeolites. In this study, we present pioneering findings regarding the synthesis of zeolites with an MFI structure (GeMFI) incorporating a high germanium amount (16% Ge). Remarkably, the germanium atoms feature a slight electron deficiency with respect to GeO, and the typical coordination number of 4, as usually reported for the germanosilicate zeolites, is exceeded, giving rise to Ge dimers in a double-bridge configuration.
View Article and Find Full Text PDFZeolites are crystalline microporous materials constructed by corner-sharing tetrahedra (SiO and AlO), with many industrial applications as ion exchangers, adsorbents and heterogeneous catalysts. However, the presence of micropores impedes the use of zeolites in areas dealing with bulky substrates. Introducing extrinsic mesopores, that is, intercrystal/intracrystal mesopores, in zeolites is a solution to overcome the diffusion barrier.
View Article and Find Full Text PDFUnlabelled: Isolated gastric Crohn's disease (IGCD) is a rare manifestation of Crohn's disease confined to the stomach, unlike its more common forms that primarily affect the ileum and colon. We report the case of a 25-year-old female presenting with a one-month history of epigastric discomfort and nausea, with no other significant gastrointestinal or systemic symptoms. Upper endoscopy revealed an aphthous ulceration on the greater curvature of the stomach, with biopsies showing non-caseating granulomas consistent with Crohn's disease.
View Article and Find Full Text PDFIn this study, we assessed the quantity, strength, and acidity of zeolite composites comprising Silicalite-1 grown on ZSM-5 crystals using a combination of infrared (IR) and solid-state nuclear magnetic resonance (NMR) spectroscopy. The composites were created through the direct growth of Silicalite-1 crystals on ZSM-5 (P_ZSM-5), either with or without the organic structure-directing agent (OSDA) introduced into the ZSM-5 channels (samples: H_ZSM-5_Sil1 and TPA_ZSM-5_Sil1). The results revealed that Silicalite-1 grew differently when the ZSM-5 core was in the H form (empty pores) compared to when the OSDA was still present in the sample.
View Article and Find Full Text PDFClin Liver Dis (Hoboken)
April 2024
Purpose: Targeted Agent and Profiling Utilization Registry is a phase II basket trial evaluating the antitumor activity of commercially available targeted agents in patients with advanced cancer with genomic alterations known to be drug targets. Results of a cohort of patients with solid tumors with alterations treated with regorafenib are reported.
Methods: Eligible patients had measurable disease (RECIST v.
Numerous pieces of evidence in the literature suggest that zeolitic materials exhibit significant intrinsic flexibility as a consequence of the spring-like behavior of Si-O and Al-O bonds and the distortion ability of Si-O-Si and Al-O-Si angles. Understanding the origin of flexibility and how it may be tuned to afford high adsorption selectivity in zeolites is a big challenge. Zeolite flexibility may be triggered by changes in temperature, pressure, or chemical composition of the framework and extra-framework compounds, as well as by the presence of guest molecules.
View Article and Find Full Text PDFNeurological diseases, including neurodegenerative and neurodevelopmental disorders, affect nearly one in six of the world's population. The burden of the resulting deaths and disability is set to rise during the next few decades as a consequence of an aging population. To address this, zebrafish have become increasingly prominent as a model for studying human neurological diseases and exploring potential therapies.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
September 2023
This study has the novel aim of experimentally examining the efficiency of a pilot-scale treatment plant, composed of a multi-tube type falling-film distillation column equipped with a biphasic thermosiphon, for treating a real sample of high-salinity produced water (electrical conductivity of 20,700 μS cm). It investigates the influence of operational parameters, including feed temperature and steam chamber temperature of the biphasic thermosiphon, on distillate flow rate and reduction of conductivity. All experimental conditions tested achieved a reduction greater than 98% in terms of electrical conductivity.
View Article and Find Full Text PDFBackground: Fighter pilots are a specific population in which any adverse drug reaction can unpredictably interact with aeronautical constraints and thus compromise flight safety. This issue has not been evaluated in risk assessments.
Aim: To provide a semi-quantitative assessment of the risk to flight safety of self-medication in fighter pilots.
Silanols are key players in the application performance of zeolites, yet, their localization and hydrogen bonding strength need more studies. The effects of post-synthetic ion exchange on nanosized chabazite (CHA), focusing on the formation of silanols, were studied. The significant alteration of the silanols of the chabazite nanozeolite upon ion exchange and their effect on the CO adsorption capacity was revealed by solid-state nuclear magnetic resonance (NMR), Fourier-transform infrared (FTIR) spectroscopy, and periodic density functional theory (DFT) calculations.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
February 2023
Intensive research on improving the catalytic properties of zeolites is focused on modulating their acidity and the distribution of associated Al sites. Herein, by studying a series of ZSM-5 zeolites over a broad range of Al content, we demonstrate how the nature of the mineralizing agent (F or OH ) used in hydrothermal syntheses directly impacts Al sites distribution. The proportions of Al sites, probed by Al NMR, depend on the Si/Al ratio for F , but remain identical for OH (from Si/Al=30 to 760).
View Article and Find Full Text PDFThe precise location and role of all types of hydroxyls in zeolites are still enigmatic, and their control permits tailoring of novel properties increasing the efficiency of catalysts and adsorbents in industrial processes for cleaner energy.
View Article and Find Full Text PDFThis paper deals with the extension of the synthesis field of microporous zeolite-type materials and types of organic structure-directing agents (OSDA) that can be used to promote their crystallization. The highly hydrophilic hexamethylenetetramine (urotropine), with its C/N ratio = 1.5, which is unusual to act as a structure-directing agent in the crystallization of open-framework silica polymorphs, is used to exemplify the novelty of the employed approach.
View Article and Find Full Text PDFPurpose: Polypharmacy is prevalent in older adults starting cancer treatment and associated with potentially inappropriate medications (PIM), potential drug-drug interactions (DDI), and drug-cancer treatment interactions (DCI). For a large cohort of vulnerable older adults with advanced cancer starting treatment, we describe patterns of prescription and nonprescription medication usage, the prevalence of PIM, and the prevalence, severity, and type of DDI/DCI.
Methods: This secondary analysis used baseline data from a randomized study enrolling patients aged ≥70 years with advanced cancer starting a new systemic cancer treatment (University of Rochester Cancer Center [URCC] 13059; PI: Mohile).
Chemoradiotherapy (CRT) for locally-advanced head and neck squamous cell carcinoma (LA-HSNCC) yields 5-year survival rates near 50% despite causing significant toxicity. Dichloroacetate (DCA), a pyruvate dehydrogenase kinase metabolic inhibitor, reduces tumor lactate production and has been used in cancer therapy previously. The safety of adding this agent to CRT is unknown.
View Article and Find Full Text PDFIn this work we show the use of high-resolution H MAS NMR to distinguish between two kinds of aggregation states of (1,2)-ephedrine, a chiral organic structure directing agent, occluded within AFI-type microporous aluminophosphates. We investigate in particular the supramolecular assembly of the molecules through π⋯π type interactions of their aromatic rings when confined within the one-dimensional AFI channels. A series of high-resolution two-dimensional spin diffusion spectra combined with molecular simulations and DFT calculations allowed us to distinguish different aggregation states of ephedrine molecules and precisely estimate the distances between the aromatic rings and their closest protons inside the zeolite channels as a consequence of distinct proton spin diffusion profiles.
View Article and Find Full Text PDFIntroduction: The extraction of maxillary first premolars is usually the treatment of choice to resolve crowding, alveolar protrusion, or Class II malocclusion. The demand for a lingual orthodontic treatment is increasing because of its esthetic value; therefore, understanding lingual biomechanics is essential to every clinician. This study compared the 3-dimensional (3D) effects of sliding mechanics in labial and lingual orthodontics using the finite element method.
View Article and Find Full Text PDFThe preparation of defect-free MFI crystals containing single-site framework Mo through a hydrothermal postsynthesis treatment is reported. The insertion of single Mo sites in the MFI zeolite samples with different crystal sizes of 100, 200, and 2000 nm presenting a diverse concentration of silanol groups is revealed. The nature of the silanols and their role in the incorporation of Mo into the zeolite structure are elucidated through an extensive spectroscopic characterization (Si NMR, H NMR, P NMR, and IR) combined with X-ray diffraction and HRTEM.
View Article and Find Full Text PDFZeolites have been game-changing materials in oil refining and petrochemistry over the last 60 years and have the potential to play the same role in the emerging processes of the energy and environmental transition. Although zeolites are crystalline inorganic solids, their structures are not perfect and the presence of defect sites - mainly Brønsted acid sites and silanols - influences their thermal and chemical resistance as well as their performances in key areas such as catalysis, gas and liquid separations and ion-exchange. In this paper, we review the type of defects in zeolites and the characterization techniques used for their identification and quantification with the focus on diffraction, spectroscopic and modeling approaches.
View Article and Find Full Text PDFBackground: Aging-related deficits that eventually manifest as frailty may be associated with poor emotional health in older patients with advanced cancer. This study aimed to examine the relationship between frailty and emotional health in this population.
Methods: This was a secondary analysis of baseline data from a nationwide cluster randomized trial.