Waxes comprise a diverse set of materials from lubricants and coatings to biological materials such as the intracuticular wax layers on plant leaves that restrict water loss to inhibit dehydration. Despite the often mixed hydrocarbon chain lengths and functional groups within waxes, they show a propensity for ordering into crystalline phases, albeit with a wealth of solid solution behavior and disorder modes that determine chemical transport and mechanical properties. Here, we reveal the microscopic structure and heterogeneity of replica leaf wax models based on the dominant wax types in the plant, namely CH and CHOH and their binary mixtures.
View Article and Find Full Text PDFObjectives: Behavioral factors of pain catastrophizing and perceived injustice are associated with pain intensity in chronic pain. Diminished heart rate variability (HRV) is also strongly associated with chronic pain. These factors have been less explored earlier in the pain experience and it is unclear whether they play a role in the transition from acute to chronic pain.
View Article and Find Full Text PDFFrontloading home care visits has been found to be effective in the nursing profession but has not been investigated in physical therapy (PT) practice. This study aimed to examine the impact of frontloading home PT visits on function in persons with heart failure (HF). This was a prospective multi-center randomized controlled trial with blinded raters.
View Article and Find Full Text PDFThe purpose of this study was to observe if core stabilization training plays a significant role in firefighter time-to-completion during a functional performance test. A within subjects study design was used in which subjects ( = 13, 84.6% male, 33.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
October 2024
Single-atom catalysts (SACs) are an emerging class of materials, leveraging maximum atom utilization and distinctive structural and electronic properties to bridge heterogeneous and homogeneous catalysis. Direct imaging methods, such as aberration-corrected high-angle annular dark-field scanning transmission electron microscopy, are commonly applied to confirm the atomic dispersion of active sites. However, interpretations of data from these techniques can be challenging due to simultaneous contributions to intensity from impurities introduced during synthesis processes, as well as any variation in position relative to the focal plane of the electron beam.
View Article and Find Full Text PDFBackground/purpose: No studies have observed the effects of a collegiate lacrosse season on movement pattern quality, dynamic postural control, or the accuracy of athletes' perceived movement pattern quality. The purpose was to examine the effects of a nontraditional fall season on movement pattern quality, perceived movement pattern quality, and dynamic postural control in collegiate lacrosse athletes.
Design: Cross-sectional laboratory study.
Systematic control and design of solid-state chemical reactions are required for modifying materials properties and in novel synthesis. Understanding chemical dynamics at the nanoscale is therefore essential to revealing the key reactive pathways. Herein, we combine focused ion beam-scanning electron microscopy (FIB-SEM) and time-of-flight secondary ion mass spectrometry (TOF-SIMS) to track the migration of sodium from a borate coating to the oxide scale during hot corrosion testing.
View Article and Find Full Text PDFMild traumatic brain injury (mTBI) is a leading cause of disability in the United States, with neuropsychiatric disturbances such as depression, anxiety, PTSD, and social disturbances being common comorbidities following injury. The molecular mechanisms driving neuropsychiatric complications following neurotrauma are not well understood and current FDA-approved pharmacotherapies employed to ameliorate these comorbidities lack desired efficacy. Concerted efforts to understand the molecular mechanisms of and identify novel drug candidates for treating neurotrauma-elicited neuropsychiatric sequelae are clearly needed.
View Article and Find Full Text PDFRecently, increased attention has been focused on amorphous metal-organic frameworks (MOFs) and, more specifically, MOF glasses, the first new glass category discovered since the 1970s. In this work, we explore the fabrication of a compositional series of hybrid blends, the first example of blending a MOF and inorganic glass. We combine ZIF-62(Zn) glass and an inorganic glass, 30NaO-70PO, to combine the chemical versatility of the MOF glass with the mechanical properties of the inorganic glass.
View Article and Find Full Text PDFWe present an approach to harnessing the tuneable catalytic properties of complex nanomaterials for continuous flow heterogeneous catalysis by combining them with the scalable and industrially implementable properties of carbon pelleted supports. This approach, in turn, will enable these catalytic materials, which largely currently exist in forms unsuitable for this application ( powders), to be fully integrated into large scale, chemical processes. A composite heterogeneous catalyst consisting of a metal-organic framework-based Lewis acid, MIL-100(Sc), immobilised onto polymer-based spherical activated carbon (PBSAC) support has been developed.
View Article and Find Full Text PDFPalladium nanoparticles stabilised by aniline modified polymer immobilised ionic liquid is a remarkably active catalyst for the hydrogenation of CO to formate; the initial TOF of 500 h is markedly higher than either unmodified catalyst or its benzylamine and ,-dimethylaniline modified counterparts and is among the highest to be reported for a PdNP-based catalyst.
View Article and Find Full Text PDFThe health care industry has sought to reduce errors and patient harm by drawing upon human factors research developed largely in the aviation industry. However, literature that explicitly applies human factors concepts to physical therapist practice is scarce. Therefore, this clinical perspective highlights the key concepts in aviation safety and training that should be considered for application to physical therapist education and practice in the acute care setting, including the law of primacy, pilot in command, crew resource management, situational awareness, the instrument scan, currency versus proficiency, the advanced qualification program, and the use of checklists.
View Article and Find Full Text PDFLead mixed-halide perovskites offer tunable bandgaps for optoelectronic applications, but illumination-induced phase segregation can quickly lead to changes in their crystal structure, bandgaps, and optoelectronic properties, especially for the Br-I mixed system because CsPbI3 tends to form a non-perovskite phase under ambient conditions. These behaviors can impact their performance in practical applications. By embedding such mixed-halide perovskites in a glassy metal-organic framework, a family of stable nanocomposites with tunable emission is created.
View Article and Find Full Text PDFDrug-delivery systems based on polymeric nanoparticles are useful for improving drug bioavailability and/or delivery of the active ingredient for example directly to the cancerous tumour. The physical and chemical characterization of a functionalized nanoparticle system is required to measure drug loading and dispersion but also to understand and model the rate and extent of drug release to help predict performance. Many techniques can be used, however, difficulties related to structure determination and identifying the precise location of the drug fraction make mathematical prediction complex and in many published examples the final conclusions are based on assumptions regarding an expected structure.
View Article and Find Full Text PDFIntentionally disordered metal-organic frameworks (MOFs) display rich functional behaviour. However, the characterisation of their atomic structures remains incredibly challenging. X-ray pair distribution function techniques have been pivotal in determining their average local structure but are largely insensitive to spatial variations in the structure.
View Article and Find Full Text PDFAcceleration/deceleration forces are a common component of various causes of mild traumatic brain injury (mTBI) and result in strain and shear forces on brain tissue. A small quantifiable volume dubbed the compensatory reserve volume (CRV) permits energy transmission to brain tissue during acceleration/deceleration events. The CRV is principally regulated by cerebral blood flow (CBF) and CBF is primarily determined by the concentration of inspired carbon dioxide (CO).
View Article and Find Full Text PDFIntroduction: Traumatic brain injury (TBI) can lead to neurocognitive decline, in part due to phosphorylated tau (p-tau). Whether p-tau accumulation worsens in the setting of polytrauma remains unknown. Propranolol has shown clinical benefit in head injuries; however, the underlying mechanism is also unknown.
View Article and Find Full Text PDFCharacterization of nanoscale changes in the atomic structure of amorphous materials is a profound challenge. Established X-ray and neutron total scattering methods typically provide sufficient signal quality only over macroscopic volumes. Pair distribution function analysis using electron scattering (ePDF) in the scanning transmission electron microscope (STEM) has emerged as a method of probing nanovolumes of these materials, but inorganic glasses as well as metal-organic frameworks (MOFs) and many other materials containing organic components are characteristically prone to irreversible changes after limited electron beam exposures.
View Article and Find Full Text PDFThe monoamine neurotransmitter serotonin (5-HT) is important for the regulation of behavior, and aberrations in 5-HT signaling are linked to several neuropsychiatric and neurodevelopmental disorders. 5-HT signaling is dependent on and tightly regulated by the functional activity of the 5-HT transporter (SERT). Neurotrauma is known to structurally and functionally impact 5-HT neuronal tracts and 5-HT signaling; however, the extent to which various forms of neurotrauma alter homeostatic 5-HT signaling through the modulation of SERT expression and/or functional uptake capacity is currently not well characterized.
View Article and Find Full Text PDFThe ability to tailor the properties of metal centers in single-atom heterogeneous catalysts depends on the availability of advanced approaches for characterization of their structure. Except for specific host materials with well-defined metal adsorption sites, determining the local atomic environment remains a crucial challenge, often relying heavily on simulations. This article reports an advanced analysis of platinum atoms stabilized on poly(triazine imide), a nanocrystalline form of carbon nitride.
View Article and Find Full Text PDFSingle-atom catalytic sites may have existed in all supported transition metal catalysts since their first application. Yet, interest in the design of single-atom heterogeneous catalysts (SACs) only really grew when advances in transmission electron microscopy (TEM) permitted direct confirmation of metal site isolation. While atomic-resolution imaging remains a central characterization tool, poor statistical significance, reproducibility, and interoperability limit its scope for deriving robust characteristics about these frontier catalytic materials.
View Article and Find Full Text PDFThe interaction of high-energy electrons and X-ray photons with beam-sensitive semiconductors such as halide perovskites is essential for the characterization and understanding of these optoelectronic materials. Using nanoprobe diffraction techniques, which can investigate physical properties on the nanoscale, studies of the interaction of electron and X-ray radiation with state-of-the-art (FA MA Cs )Pb(I Br ) hybrid halide perovskite films (FA, formamidinium; MA, methylammonium) are performed, tracking the changes in the local crystal structure as a function of fluence using scanning electron diffraction and synchrotron nano X-ray diffraction techniques. Perovskite grains are identified, from which additional reflections, corresponding to PbBr , appear as a crystalline degradation phase after fluences of 200 e Å .
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