J Pediatr Adolesc Gynecol
August 2024
Study Objective: Uptake of intrauterine devices (IUDs) in the adolescent population may be limited by anxiety and pain anticipated during the insertion procedure. Our institution offers conscious sedation for IUD insertion to mitigate this concern. The objective of this study was to identify characteristics and outcomes of teens choosing between two types of conscious sedation for insertion of a levonorgestrel IUD.
View Article and Find Full Text PDFBackground: For adolescents with suspected polycystic ovary syndrome (PCOS) and severely elevated testosterone concentrations, imaging is recommended to assess for neoplasm. Selective venous sampling (SVS) can be considered when imaging is nondiagnostic.
Case: An adolescent female treated for PCOS had a peak testosterone of 344 ng/dL (11.
The bacterial metallo-β-lactamases (MBLs) catalyze the inactivation of β-lactam antibiotics. Identifying novel pharmacophores remains crucial for the clinical development of additional MBL inhibitors. Previously, 1-hydroxypyridine-2(1H)-thione-6-carboxylic acid, hereafter referred to as 1,2-HPT-6-COOH, was reported as a low cytotoxic nanomolar β-lactamase inhibitor of Verona-integron-encoded metallo-β-lactamase 2, capable of rescuing β-lactam antibiotic activity.
View Article and Find Full Text PDFTime-of-flight secondary ion mass spectrometry (TOF-SIMS) is a powerful chemical characterization technique allowing for the distribution of all material components (including light and heavy elements and molecules) to be analyzed in 3D with nanoscale resolution. Furthermore, the sample's surface can be probed over a wide analytical area range (usually between 1 µm and 10 µm) providing insights into local variations in sample composition, as well as giving a general overview of the sample's structure. Finally, as long as the sample's surface is flat and conductive, no additional sample preparation is needed prior to TOF-SIMS measurements.
View Article and Find Full Text PDFMassive demand for Li-ion batteries stimulates the research of new materials such as high-capacity cathodes, metal anodes, and solid electrolytes, which should ultimately lead to new generations of batteries such as all-solid-state batteries. Such material discovery often requires knowledge on lithium's content and local distribution in complex Li-containing systems, which is a challenging analytical task. The state-of-the-art time-of-flight secondary-ion mass spectrometry (TOF-SIMS) is one of the few chemical analysis techniques allowing for parallel detection of all sample components and representing their distributions in 3D with nanoscale resolution.
View Article and Find Full Text PDFRecent developments in nanoprinting using focused electron beams have created a need to develop analysis methods for the products of electron-induced fragmentation of different metalorganic compounds. The original approach used here is termed focused-electron-beam-induced mass spectrometry (FEBiMS). FEBiMS enables the investigation of the fragmentation of electron-sensitive materials during irradiation within the typical primary electron beam energy range of a scanning electron microscope (0.
View Article and Find Full Text PDFDue to excellent electric conductivity and chemical inertness, Au can be used in new microdevices for energy applications, microelectronics, and biomedical solutions. However, the chemical analysis of Au-containing systems using time-of-flight secondary ion mass spectrometry (TOF-SIMS) can be difficult because of the negative ionization of Au, as most metals form positive ions, and therefore cannot be detected from the same analytical volume. In this work, we present the potential of fluorine gas coinjection for altering the polarity, from the negative to positive, of Au secondary ions generated under Ga beam bombardment.
View Article and Find Full Text PDFTime-of-flight secondary ion mass spectrometry (TOF-SIMS) is one of very few analytical techniques allowing sample chemical structure to be characterized in three-dimensional (3D) with nanometer resolution. Due to the excellent sensitivity in the order of ppm-ppb and capability of detecting all ionized elements and molecules, TOF-SIMS finds many applications for analyzing nanoparticle-containing systems and thin films used in microdevices for new energy applications, microelectronics, and biomedicine. However, one of the main drawbacks of this technique is potential mass interference between ions having the same or similar masses, which can lead to data misinterpretation.
View Article and Find Full Text PDFIn this work, we present the potential of high vacuum-compatible time-of-flight secondary ion mass spectrometry (TOF-SIMS) detectors, which can be integrated within focused ion beam (FIB) instruments for precise and fast chemical characterization of thin films buried deep under the sample surface. This is demonstrated on complex multilayer systems composed of alternating ceramic and metallic layers with thicknesses varying from several nanometers to hundreds of nanometers. The typical problems of the TOF-SIMS technique, that is, low secondary ion signals and mass interference between ions having similar masses, were solved using a novel approach of co-injecting fluorine gas during the sample surface sputtering.
View Article and Find Full Text PDFIn this work, we present a comprehensive comparison of time-of-flight secondary ion mass spectrometry (TOF-SIMS) and scanning transmission electron microscopy combined with energy-dispersive X-ray spectroscopy (STEM/EDX), which are currently the most powerful elemental characterization techniques in the nano- and microscale. The potential and limitations of these methods are verified using a novel dedicated model sample consisting of Al nanoparticles buried under a 50 nm thick Cu thin film. The sample design based on the low concentration of nanoparticles allowed us to demonstrate the capability of TOF-SIMS to spatially resolve individual tens of nanometer large nanoparticles under ultrahigh vacuum (UHV) as well as high vacuum (HV) conditions.
View Article and Find Full Text PDFInt J Mol Sci
December 2019
The ability of 2-deoxy-d-glucose (2-DG) to interfere with d-glucose metabolism demonstrates that nutrient and energy deprivation is an efficient tool to suppress cancer cell growth and survival. Acting as a d-glucose mimic, 2-DG inhibits glycolysis due to formation and intracellular accumulation of 2-deoxy-d-glucose-6-phosphate (2-DG6P), inhibiting the function of hexokinase and glucose-6-phosphate isomerase, and inducing cell death. In addition to glycolysis inhibition, other molecular processes are also affected by 2-DG.
View Article and Find Full Text PDFTime-of-flight secondary ion mass spectrometry (TOF-SIMS) detectors have been intensively developed in recent decades due to their unprecedented capability of representing a sample elemental composition in a three-dimensional space from nano- to submilliscale with high spatial resolution and mass resolution. A compact high-vacuum-compatible version of these detectors can be integrated into a focused ion beam (FIB) system which, assembled with scanning electron microscopy (SEM), is the most popular tool used in nanotechnology and material science. This gives a new opportunity for combining TOF-SIMS analysis with other instruments within the same analytical chamber.
View Article and Find Full Text PDFCombining a Gas-Injection System (GIS) with the Focused Ion Beam (FIB) has a broad scope of applications in sample preparation such as protective layer deposition, increasing material sputtering rates, and reducing FIB-related artifacts. On the other hand, injecting certain specific gases during a Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) analysis can significantly increase element ionization probability and, therefore, improve the quality of 3D representation of a sample elemental structure. In this work, for the first time, the potential of GIS for enhancing secondary ion signals acquired using a TOF detector incorporated into a commercial Ga FIB-SEM (Focused Ion Beam combined with Scanning Electron Microscope) instrument is presented.
View Article and Find Full Text PDFImaging nano-objects in complex systems such as nanocomposites using time-of-flight secondary ion mass spectrometry (TOF-SIMS) is a challenging task. Due to a very small amount of the material and a matrix effect, the number of generated secondary ions can be insufficient to represent a 3D elemental distribution despite being detected in a mass spectrum. Therefore, a model sample consisting of a ZrCuAg matrix with embedded Al nanoparticles is designed.
View Article and Find Full Text PDFStructural defects such as voids and compositional inhomogeneities may affect the performance of Cu(In,Ga)Se (CIGS) solar cells. We analyzed the morphology and elemental distributions in co-evaporated CIGS thin films at the different stages of the CIGS growth by energy-dispersive x-ray spectroscopy in a transmission electron microscope. Accumulation of Cu-Se phases was found at crevices and at grain boundaries after the Cu-rich intermediate stage of the CIGS deposition sequence.
View Article and Find Full Text PDFThe potential of a novel caesium evaporator for enhancing negative secondary ion yields during Focused Ion Beam Time-Of-Flight Secondary Ion Mass Spectrometry (FIB-TOF-SIMS) elemental analysis is presented. The design of the lab prototype Cs evaporator is based on alkali metal dispensers containing a stable Cs salt and therefore it can be safely used for FIB-TOF-SIMS measurements under high vacuum conditions. Continuous in-situ Cs deposition on an Au sample surface has allowed the TOF-SIMS signal to be increased by a factor of 260, which confirms the functionality of the technique.
View Article and Find Full Text PDFPurpose: Search for alternate pain medications has gained more importance in the past few years due to adverse effects associated with currently prescribed drugs including nervous system dysfunction with opioids, gastrointestinal discomfort with nonsteroidal anti-inflammatory drugs, and cardiovascular anomalies with cyclooxygenase-2 (COX-2) inhibitors. Phytomedicine has been explored for the treatment of pain, as these have been used for generations in regional communities and tend to lack major side effects in general. One such phytomedicine, incarvillateine (INCA), derived from the Chinese herb has its primary antinociceptive action through the adenosine receptor, a novel pain target.
View Article and Find Full Text PDFJ Public Health Manag Pract
June 2018
The Primary Care Capacity Project (PCCP), implemented by the Louisiana Public Health Institute, systematically and rigorously applied qualitative methodologies beyond simple interviews and focus groups to develop the project areas of focus, evaluate clinical transformation interventions in selected heath centers along the Gulf Coast, and provide data and support to foster ongoing quality improvement approaches. Qualitative methodologies were utilized for formative, implementation, and summative evaluation. During the early formative stages of PCCP, community prioritization meetings were conducted in Louisiana, Mississippi, Alabama, and Florida, in which key stakeholders were asked to brainstorm and prioritize major health issues and recommendations in their communities.
View Article and Find Full Text PDFThe prevalence of dual diagnosis, that is, the combination of psychiatric illnesses and substance use disorders, is high. As a vast majority of previous research in this context focusses on the effects of different treatment methods, rather than interpersonal issues, the purpose of the present study was to explore and illuminate in what way patients with a dual diagnosis experience conversations with nurses in an outpatient clinic to be caring. Five patients were interviewed regarding their experiences of caring conversations.
View Article and Find Full Text PDFIn this paper the potential of time-of-flight secondary ion mass spectroscopy combined with focused ion beam technology to characterize the composition of a solid oxide fuel cell (SOFC) in three-dimension is demonstrated. The very high sensitivity of this method allows even very small amounts of elements/compounds to be detected and localized. Therefore, interlayer diffusion of elements between porous electrodes and presence of pollutants can be analyzed with a spatial resolution of the order of 100 nm.
View Article and Find Full Text PDFWe present a novel sample preparation method that allows correlative 3D X-ray Computed Nano-Tomography (CNT) and Focused Ion Beam Time-Of-Flight Secondary Ion Mass Spectrometry (FIB-TOF-SIMS) tomography to be performed on the same sample. In addition, our invention ensures that samples stay unmodified structurally and chemically between the subsequent experiments. The main principle is based on modifying the topography of the X-ray CNT experimental setup before FIB-TOF-SIMS measurements by incorporating a square washer around the sample.
View Article and Find Full Text PDFThis paper shows how X-ray computed nanotomography (CNT) can be correlated with focused ion beam time-of-flight secondary ion mass spectrometry (FIB-TOF-SIMS) tomography on the same sample to investigate both the morphological and elemental structure. This methodology is applicable to relatively large specimens with dimensions of several tens of microns whilst maintaining a high spatial resolution of the order of 100 nm. However, combining X-ray CNT and FIB-TOF-SIMS tomography requires innovative sample preparation protocols to allow both experiments to be conducted on exactly the same sample without chemically or structurally modifying the sample between measurements.
View Article and Find Full Text PDFThis study employs a novel strategy for identifying points of resistance to education efforts aimed at reducing rates of child physical abuse and use of corporal punishment (CP). We analyzed online comments (n = 581) generated in response to media coverage of a study linking CP with increased child aggression. Most comments (71%) reflected approval of hitting children for disciplinary purposes.
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