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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 Schefflera elegantissimaplant, namely C31H64and C30H61OH and their binary mixtures. We observe defined grain microstructure in C31H64crystals and nanoscale domains of chain-ordered lamellae within these grains. Moreover, nematic phases and dynamical disorder coexist with the domains of ordered lamellae. C30H61OH exhibits more disordered chain packing with no grain structure or lamellar domains. Binary mixtures from 0–50% C30H61OH exhibit a loss of grain structure with increasing alcohol content accompanied by increasingly nematic rather than lamellar chain packing, suggesting a partial but limited solid solution behavior. Together, these results unveil the previously unseen microstructural features governing flexibility and permeability in leaf waxes and outline an approach to microstructure analysis across agrochemicals, pharmaceuticals, and food.

The 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. We aimed to better characterize the protein expression and uptake activity of SERT following mild traumatic brain injury (mTBI). A murine model of blast-induced mTBI was utilized to characterize alterations in SERT expression and function following injury. mTBI was found to decrease (≈26%) the protein levels of SERT 3 days postinjury (DPI) in the dorsal raphe nucleus (DRN), the primary locale of 5-HT neuronal cell bodies within the central nervous system. Concomitant reductions in midbrain SERT-dependent radiolabeled 5-HT uptake were observed 3 DPI (≈24%). No alterations in SERT expression were observed 10 DPI in the DRN. Additionally, no alterations in SERT expression or function were observed in prefrontal cortex samples at any time point observed. This data reveals time- and location-dependent alterations in SERT expression and function following mTBI. These studies illustrate the critical importance of ongoing research efforts to characterize the molecular effects of various forms of neurotrauma on SERT protein expression and function, which may yield novel drug targets within 5-HT systems.

The American Physical Therapy Association (APTA), in conjunction with the Cardiovascular and Pulmonary Section of APTA, published a clinical practice guideline (CPG) in January 2020 in the Physical Therapy journal to assist physical therapists in their clinical decision-making when treating patients with heart failure (HF). The purpose of this executive summary is to briefly describe the major themes of the CPG and provide current recommendations for evidence-based interventions in the management of patients with HF. A summary table of the 9 key action statements along with clinical algorithms guides the physical therapist in appropriate clinical decision-making.

Austin, AB, Collins, SM, Huggins, RA, Smith, BA, and Bowman, TG. The impact of environmental conditions on player loads during preseason training sessions in women's soccer athletes. J Strength Cond Res35(10): 2775–2782, 2021—Our objective was to determine the impact of environmental conditions on player loads during preseason training sessions in women's soccer athletes. Eleven women's NCAA Division III soccer players (age = 20 ± 1 year, height = 167.28 ± 8.65 cm, body mass = 60.18 ± 5.42 kg, V̇o2max = 43.70 ± 3.95 ml·kg−1·min−1) volunteered to wear Global Positioning System (GPS) devices (Sports Performance Tracking, Melbourne, Australia) that provided measures of training session external intensity throughout all preseason practices (n= 15). We recorded wet-bulb globe temperature (WBGT), session Rating of Perceived Exertion-Training Load (sRPE-TL), and ΔBM during each preseason training session and set α ≤ 0.05. The combination of WBGT, sRPE-TL, and ΔBM explained 34% of the variance in GPS-based intensity score (proprietary measure) (F3,153= 26.25, p< 0.001). Wet-bulb globe temperature (t156= −2.58, p= 0.01), sRPE (t156= 8.24, p< 0.001), and ΔBM (t156= 2.39, p= 0.02) were significantly associated with intensity. The ΔBM from prepractice (60.00 ± 5.21 kg) to postpractice (59.61 ± 5.10 kg) was statistically significant (p< 0.001); however, ΔBM from the beginning of preseason (59.87 ± 5.31 kg) to the end of preseason (59.91 ± 5.58 kg) was not significant (p= 0.89). Despite relatively low to moderate environmental conditions, increases in WBGT were associated with reductions in GPS intensity and elevated internal load via sRPE-TL. Our findings support the association between exercise intensity and WBGT, internal load, and hydration status; thus, coaches and exercise scientists should take these factors into account when monitoring or interpreting intensity metrics. Furthermore, these findings support the continued use of environmental monitoring and hydration best-practice policies to limit exercise intensity in the heat so as to mitigate excessive heat stress.

Nature controls the assembly of complex architectures through self-limiting processes; however, few artificial strategies to mimic these processes have been reported to date. Here we demonstrate a system comprising two types of nanocrystal (NC), where the self-limiting assembly of one NC component controls the aggregation of the other. Our strategy uses semiconducting InP/ZnS core–shell NCs (3 nm) as effective assembly modulators and functional nanoparticle surfactants in cucurbit[n]uril-triggered aggregation of AuNCs (5–60 nm), allowing the rapid formation (within seconds) of colloidally stable hybrid aggregates. The resultant assemblies efficiently harvest light within the semiconductor substructures, inducing out-of-equilibrium electron transfer processes, which can now be simultaneously monitored through the incorporated surface-enhanced Raman spectroscopy–active plasmonic compartments. Spatial confinement of electron mediators (for example, methyl viologen (MV2+)) within the hybrids enables the direct observation of photogenerated radical species as well as molecular recognition in real time, providing experimental evidence for the formation of elusive σ–(MV+)2dimeric species. This approach paves the way for widespread use of analogous hybrids for the long-term real-time tracking of interfacial charge transfer processes, such as the light-driven generation of radicals and catalysis with operando spectroscopies under irreversible conditions.

Defect engineering can enhance key properties of metal–organic frameworks (MOFs). Tailoring the distribution of defects, for example in correlated nanodomains, requires characterization across length scales. However, a critical nanoscale characterization gap has emerged between the bulk diffraction techniques used to detect defect nanodomains and the subnanometer imaging used to observe individual defects. Here, we demonstrate that the emerging technique of scanning electron diffraction (SED) can bridge this gap uniquely enabling both nanoscale crystallographic analysis and the low-dose formation of multiple diffraction contrast images for defect analysis in MOFs. We directly image defect nanodomains in the MOF UiO-66(Hf) over an area of ca. 1000 nm and with a spatial resolution ca. 5 nm to reveal domain morphology and distribution. Based on these observations, we suggest possible crystal growth processes underpinning synthetic control of defect nanodomains. We also identify likely dislocations and small angle grain boundaries, illustrating that SED could be a key technique in developing the potential for engineering the distribution of defects, or “microstructure”, in functional MOF design.

Advances in the production of two-dimensional (2D) materials such as graphene and MoS2during the past two decades have spurred the search for other van der Waals materials with distinct functional properties. However, reducing the dimensionality of bulk van der Waals materials can lead to structural rearrangement and chemical degradation, especially in the presence of air. These challenges have slowed the progress of the discovery and analysis of chemically diverse 2D materials. Here, we provide a case study on the shear exfoliation of a class of wide band gap van der Waals materials termed II–VI layered hybrids (II–VI LHs) and show how reducing their dimension influences their structural and chemical stabilities. ZnSe(butylamine) and ZnSe(octylamine) are exfoliated, yielding shear-thinned material whose resistance toward degradation via oxidation is studied in depth by a variety of macro- and microscopic characterization techniques. Mechanical energy input, solvent–ligand interaction, and exposure to ambient conditions all play important roles in the stability of these materials. Our findings suggest that moderately coordinating alkylamine layers stabilize 2D materials that would otherwise degrade during exfoliation and exposure to air.

Vibrational spectroscopies directly record details of bonding in materials, but spatially resolved methods have been limited to surface techniques for mapping functional groups at the nanoscale. Electron energy loss spectroscopy (EELS) in the scanning transmission electron microscope presents a route to functional group analysis from nanoscale volumes using transmitted subnanometer electron probes. Here, we now use vibrational EELS to map distinct carboxylate and imidazolate linkers in a metal–organic framework (MOF) crystal–glass composite material. Domains <100 nm in size are observed using vibrational EELS, with recorded spatial resolution <15 nm at interfaces in the composite. This nanoscale functional group mapping is confirmed by correlated EELS at core ionization edges as well as X-ray energy dispersive spectroscopy for elemental mapping of the metal centers of the two constituent MOFs. These results present a complete nanoscale analysis of the building blocks of the MOF composite and establish spatially resolved functional group analysis using electron beam spectroscopy for crystalline and amorphous organic and metal–organic solids.

The American Physical Therapy Association (APTA), in conjunction with the Cardiovascular and Pulmonary Section of APTA, have commissioned the development of this clinical practice guideline to assist physical therapists in their clinical decision making when managing patients with heart failure. Physical therapists treat patients with varying degrees of impairments and limitations in activity and participation associated with heart failure pathology across the continuum of care. This document will guide physical therapist practice in the examination and treatment of patients with a known diagnosis of heart failure. The development of this clinical practice guideline followed a structured process and resulted in 9 key action statements to guide physical therapist practice. The level and quality of available evidence were graded based on specific criteria to determine the strength of each action statement. Clinical algorithms were developed to guide the physical therapist in appropriate clinical decision making. Physical therapists are encouraged to work collaboratively with other members of the health care team in implementing these action statements to improve the activity, participation, and quality of life in individuals with heart failure and reduce the incidence of heart failure-related re-admissions.

Metal–organic framework crystal-glass composites (MOF-CGCs) are materials in which a crystalline MOF is dispersed within a MOF glass. In this work, we explore the room-temperature stabilization of the open-pore form of MIL-53(Al), usually observed at high temperature, which occurs upon encapsulation within a ZIF-62(Zn) MOF glass matrix. A series of MOF-CGCs containing different loadings of MIL-53(Al) were synthesized and characterized using X-ray diffraction and nuclear magnetic resonance spectroscopy. An upper limit of MIL-53(Al) that can be stabilized in the composite was determined for the first time. The nanostructure of the composites was probed using pair distribution function analysis and scanning transmission electron microscopy. Notably, the distribution and integrity of the crystalline component in a sample series were determined, and these findings were related to the MOF-CGC gas adsorption capacity in order to identify the optimal loading necessary for maximum CO2sorption capacity.

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 in situhot corrosion testing. We map the changing distribution of chemical elements and compounds from 50 to 850 °C to reveal how sodium diffusion induces corrosion. The results are validated by in situX-ray diffraction and post-mortem TOF-SIMS. We additionally retrieve the through-solid sodium diffusion rate by fitting measurements to a Fickian diffusion model. This study presents a step change in analyzing microscopic diffusion mechanics with high chemical sensitivity and selectivity, a widespread analytical challenge that underpins the defining rates and mechanisms of solid-state reactions.

The 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. The authors identify, discuss, and apply existing parallel concepts in physical therapist literature. The authors then challenge acute care physical therapists, academic faculty, and clinical instructors on ways to integrate these concepts in practice.

This work investigates the corrosion of offshore structural steel surfaces over particularly short timescales. The focus is on the short-term effects between surface treatment and coating application (typically several hours). Offshore structures are exposed to an aggressive marine environment, where substrates will be contaminated by aerosols containing salts within hours, even under mild weather conditions. Localised corrosion studies of the anodic and cathodic regions of S355 steel surfaces undergoing salt drop corrosion are characterised. Significantly, the corrosion products are found to grow rapidly and are inhomogeneous, porous, and amorphous. They evolve to higher oxidation state oxides quickly with corrosion time. Therefore, microscopic corrosion products will form on newly exposed substrates in marine environments, even before the protective paint is applied.

Microstructured metal–organic framework (MOF) glasses have been produced by combining two amorphous MOFs. However, the electronic structure of these materials has not been interrogated at the length scales of the chemical domains formed in these glasses. Here, we report a subwavelength spatially resolved physicochemical analysis of the electronic states at visible and UV energies in a blend of two zeolitic imidazolate frameworks (ZIFs), ZIF-4-Co and ZIF-62-Zn. By combining spectroscopy at visible and UV energies as well as at core ionization energies in electron energy loss spectroscopy in the scanning transmission electron microscope with density functional theory calculations, we show that domains less than 200 nm in size retain the electronic structure of the precursor crystalline ZIF phases. Prototypical signatures of coordination chemistry including d–dtransitions in ZIF-4-Co are assigned and mapped with nanoscale precision.

Palladium-catalysed cross-coupling reactions, central tools in fine-chemical synthesis, predominantly employ soluble metal complexes despite recognized challenges with product purification and catalyst reusability1–3. Attempts to tether these homogeneous catalysts on insoluble carriers have been thwarted by suboptimal stability, which leads to a progressively worsening performance due to metal leaching or clustering4. The alternative application of supported Pd nanoparticles has faced limitations because of insufficient activity under the mild conditions required to avoid thermal degradation of the substrates or products. Single-atom heterogeneous catalysts lie at the frontier5–18. Here, we show that the Pd atoms anchored on exfoliated graphitic carbon nitride (Pd-ECN) capture the advantages of both worlds, as they comprise a solid catalyst that matches the high chemoselectivity and broad functional group tolerance of state-of-the-art homogeneous catalysts for Suzuki couplings, and also demonstrate a robust stability in flow. The adaptive coordination environment within the macroheterocycles of ECN facilitates each catalytic step. The findings illustrate the exciting opportunities presented by nanostructuring single atoms in solid hosts for catalytic processes that remain difficult to heterogenize.

When actions generate negative externalities for third parties, incentives exist to pass these “morally costly” decisions to others. In laboratory experiments, we investigate how market interaction affects allocations when the right to divide a sum of money between oneself and a passive recipient is commoditized. Allocation to recipients is reduced by more than half when determined by subjects who purchase or keep the right to make the division as compared to a control where subjects are directly assigned the right. Sellers report accurate beliefs about recipient allocations and do not report feeling less responsible the more often they sell the allocation right. The market allocates the right to make divisions more frequently to buyers who allocate more to recipients, but sellers who allocate less to recipients tend to sell less often. Selection cannot solely explain the results, suggesting market interaction itself may directly impact behavior.

•Continuity of care is a multidimensional construct.•Three types of continuity are relevant for inpatients receiving rehabilitation.•Management continuity is the component with the most negative experiences.•Most problems experienced by the participants are aspects that can be modified.

We present a combined scanning transmission electron microscopy–electron energy loss spectroscopy (STEM–EELS) investigation into the mode symmetries of plasmonic nanoparticle trimer and tetramer structures. We obtain nanometer-resolved energy loss spectra for both trimer and tetramer structures and compare these to boundary element method simulations. We show that EELS, in conjunction with eigenmode simulations, offers a complete characterization of the individual superstructures, and we trace the evolution of both optically dark and bright modes and identify multipolar mode contributions. We then apply this technique to tetramer structures that exhibit an expanded range of mode symmetries for two-dimensional and three-dimensional self-assembled geometries. These findings provide a comprehensive experimental account of the available photonic states in self-assembled nanoparticle clusters.

Catalytic and optical properties can be coupled by combining different metals into nanoscale architectures in which both the shape and the composition provide fine-tuning of functionality. Here, discrete, small Pt nanoparticles (diameter = 3–6 nm) were grown in linear arrays on Au nanoprisms, and the resulting structures are shown to retain strong localized surface plasmon resonances. Multidimensional electron microscopy and spectroscopy techniques (energy-dispersive X-ray spectroscopy, electron tomography, and electron energy-loss spectroscopy) were used to unravel their local composition, three-dimensional morphology, growth patterns, and optical properties. The composition and tomographic analyses disclose otherwise ambiguous details of the Pt-decorated Au nanoprisms, revealing that both pseudospherical protrusions and dendritic Pt nanoparticles grow on all faces of the nanoprisms (the faceted or occasionally twisted morphologies of which are also revealed), and shed light on the alignment of the Pt nanoparticles. The electron energy-loss spectroscopy investigations show that the Au nanoprisms support multiple localized surface plasmon resonances despite the presence of pendant Pt nanoparticles. The plasmonic fields at the surface of the nanoprisms indeed extend into the Pt nanoparticles, opening possibilities for combined optical and catalytic applications. These insights pave the way toward comprehensive nanoengineering of multifunctional bimetallic nanostructures, with potential applications in plasmon-enhanced catalysis and in situ monitoring of chemical processes via surface-enhanced spectroscopy.

Nitrogen alloyed gallium phosphide (GaP1–xNx) nanowires have been prepared by annealing gallium phosphide (GaP) nanowires in flowing NH3(g) at 750 °C. X-ray diffraction patterns and electron microscopy showed that changes in the annealing conditions afforded controlled alloying of N without effecting a complete conversion to gallium nitride (GaN). Raman measurements on nanowire films and individual nanowires highlighted intense new signatures, consistent with symmetry reduction from N incorporation in the zincblende lattice. The resultant optical properties and photoresponse of the GaP1–xNxnanowire films were investigated by wavelength-dependent diffuse reflectance and photoelectrochemical measurements, respectively. Diffuse reflectance measurements showed progressively lower reflectivity of visible light for nanowire films annealed in increasingly higher levels of NH3(g), indicating an increased light absorption. Corresponding photoelectrochemical measurements of the GaP1–xNxnanowires revealed an increased quantum efficiency, relative to GaP, for energy conversion of light with wavelengths longer than 545 nm. The presented data set thus identifies a methodology for improving the solar energy conversion properties of GaP nanowire film photoelectrodes for visible light.

In this work we describe present experimental results for two related ternary phosphide materials, N-alloyed GaP and ZnGeP2. These materials represent two potential mid-bandgap photoelectrode materials for artificial photosynthetic systems for solar energy conversion/storage. For photoelectrochemical cells designed to generate energyrich chemical fuels under illumination, candidate photoelectrode materials should demonstrate the capacity to sustain large photovoltages and photocurrent densities under solar insolation. The results in this work show that the optical properties of these two materials should enable the possibilities for light collection out past 600 nm. For N-alloyed GaP nanowire films, diffuse reflectance spectra show the increase of light absorption at sub-bandgap wavelengths with increasing NH3(g) used during the annealing step. Corresponding photoelectrochemical data show that the quantum efficiency for light collection at sub-bandgap wavelengths does not follow the same monotonic trend. Separately, we report the first demonstration of ZnGeP2nanowire films. The as-prepared materials show reflectance responses consistent with a mid-bandgap material featuring a pseudo-direct bandgap.

Single-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. Here, we introduce a customized deep-learning method for automated atom detection in image analysis, a rate-limiting step toward high-throughput TEM. Platinum atoms stabilized on a functionalized carbon support with a challenging irregular three-dimensional morphology serve as a practically relevant test system with promising scope in thermo- and electrochemical applications. The model detects over 20,000 atomic positions for the statistical analysis of important properties for establishing structure–performance relations over nanostructured catalysts, like the surface density, proximity, clustering extent, and dispersion uniformity of supported metal species. Good performance obtained on direct application of the model to an iron SAC based on carbon nitride demonstrates its generalizability for single-atom detection on carbon-related materials. The approach establishes a route to integrate artificial intelligence into routine TEM workflows. It accelerates image processing times by orders of magnitude and reduces human bias by providing an uncertainty analysis that is not readily quantifiable in manual atom identification, improving standardization and scalability.