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Polymorphism grants metal–organic frameworks (MOFs) a high degree of structural diversity for various applications. Here, we describe the discovery of three new phases of zirconium-muconate MOFs, denoted as NU-412 (bct), NU-413 (bcu), and NU-414 (reo). NU-412 was first synthesized using formic acid as both modulator and coligand de novo and was crystallographically characterized. The formate coligand in NU-412 could be selectively removed to yield NU-413 with a higher degree of coordinative unsaturation at the Zr6node and maintained the channel geometry of the structure. Inspired by the intermediate NU-414 product observed during the growth of NU-412, we investigated the possibility of phase transformations as an approach to yield NU-412 and demonstrated success in accessing novel polymorphs from existing phases.

Surgery is essential for gastrointestinal (GI) cancer treatment. Many patients lack access to surgical care that optimizes outcomes. Scarce availability and/or low accessibility of appropriate resources may be the reason for this, especially in economically disadvantaged areas. This study aimed to investigate providers’ and survivors’ perspectives on barriers and facilitators to the availability and accessibility of surgical care.

This work presents a capacitor voltage balancing controller for current-controlled flying capacitor multilevel converters. A small-signal model of the converter derived from state–space averaging informs the parallel controller structure. The proposed controller incorporates nonlinear actions to decouple flying capacitor control loops and prevent adverse interaction between the capacitor voltage balancing and inductor current controllers. Experimental results of closed-loop line and load transient responses demonstrate significant performance improvements with the proposed balancing architecture compared to a converter relying on natural capacitor balancing. These improvements are quantified with experimental measurements of switch voltage stress and load current disturbance as a response to line voltage perturbations at different frequencies. Limits to control bandwidths in balancing controllers based on averaged models are discussed. The closed-loop stability of the converter operating with the proposed active balancing architecture is discussed as a function of the operating point, controller gains, and hardware parameters, such as output filter inductance and inductor current ripple.

We combined synchrotron-based infrared absorbance and Raman scattering spectroscopies with diamond anvil cell techniques and a symmetry analysis to explore the properties of multiferroic (NH4)2FeCl5·H2O under extreme pressure–temperature conditions. Compression-induced splitting of the Fe–Cl stretching, Cl–Fe–Cl and Cl–Fe–O bending, and NH4+librational modes defines two structural phase transitions, and a group–subgroup analysis reveals space group sequences that vary depending upon proximity to the unexpectedly wide order–disorder transition. We bring these findings together with prior high-field work to develop the pressure–temperature–magnetic field phase diagram uncovering competing polar, chiral, and magnetic phases in this system.

Bottlebrush polymers, macromolecules consisting of dense polymer side chains grafted from a central polymer backbone, have unique properties resulting from this well-defined molecular architecture. With the advent of controlled radical polymerization techniques, access to these architectures has become more readily available. However, synthetic challenges remain, including the need for intermediate purification, the use of toxic solvents, and challenges with achieving long bottlebrush architectures due to backbone entanglements. Herein, we report hybrid bonding bottlebrush polymers (systems integrating covalent and noncovalent bonding of structural units) consisting of poly(sodium 4-styrenesulfonate) (p(NaSS)) brushes grafted from a peptide amphiphile (PA) supramolecular polymer backbone. This was achieved using photoinitiated electron/energy transfer-reversible addition–fragmentation chain transfer (PET-RAFT) polymerization in water. The structure of the hybrid bonding bottlebrush architecture was characterized using cryogenic transmission electron microscopy, and its properties were probed using rheological measurements. We observed that hybrid bonding bottlebrush polymers were able to organize into block architectures containing domains with high brush grafting density and others with no observable brushes. This finding is possibly a result of dynamic behavior unique to supramolecular polymer backbones, enabling molecular exchange or translational diffusion of monomers along the length of the assemblies. The hybrid bottlebrush polymers exhibited higher solution viscosity at moderate shear, protected supramolecular polymer backbones from disassembly at high shear, and supported self-healing capabilities, depending on grafting densities. Our results demonstrate an opportunity for novel properties in easily synthesized bottlebrush polymer architectures built with supramolecular polymers that might be useful in biomedical applications or for aqueous lubrication.

Elicitation of effective antitumor immunity following cancer vaccination requires the selective activation of distinct effector cell populations and pathways. Here we report a therapeutic approach for generating potent T cell responses using a modular vaccination platform technology capable of inducing directed immune activation, termed the Protein-like Polymer (PLP). PLPs demonstrate increased proteolytic resistance, high uptake by antigen-presenting cells (APCs), and enhanced payload-specific T cell responses. Key design parameters, namely payload linkage chemistry, degree of polymerization, and side chain composition, were varied to optimize vaccine formulations. Linking antigens to the polymer backbone using an intracellularly cleaved disulfide bond copolymerized with a diluent amount of oligo(ethylene glycol) (OEG) resulted in the highest payload-specific potentiation of antigen immunogenicity, enhancing dendritic cell (DC) activation and antigen-specific T cell responses. Vaccination with PLPs carrying either gp100, E7, or adpgk peptides significantly increased the survival of mice inoculated with B16F10, TC-1, or MC38 tumors, respectively, without the need for adjuvants. B16F10-bearing mice immunized with gp100-carrying PLPs showed increased antitumor CD8+T cell immunity, suppressed tumor growth, and treatment synergy when paired with two distinct stimulator of interferon gene (STING) agonists. In a human papillomavirus-associated TC-1 model, combination therapy with PLP and 2′3′-cGAMP resulted in 40% of mice completely eliminating implanted tumors while also displaying curative protection from rechallenge, consistent with conferment of lasting immunological memory. Finally, PLPs can be stored long-term in a lyophilized state and are highly tunable, underscoring the unique properties of the platform for use as generalizable cancer vaccines.

While intensive studies have focused on the synthesis and characterization of new metal–organic nanotube (MONT) structures, the lack of size and morphology control remains an obstacle in broadening applications for this class of materials. Herein, we demonstrate control of MONT crystallite size and morphology by tuning polarity and the protic/aprotic nature of solvents, including dimethylformamide, N-methyl-2-pyrrolidone, ethanol, and 2-methyltetrahydrofuran, for the isostructural syntheses of two MONTs. Through a combination of transmission electron microscopy, powder X-ray diffraction, and selected area electron diffraction, we find that MONT crystallite sizes can be tuned while maintaining control over the relative dispersity without significantly altering the underlying crystal structure.

There is a significant gap in prevailing theories of change and resulting discipleship methodologies. This gap is the result of the dominate assumption that people are primarily thinking and doing beings and that spiritual maturity is largely a function of biblical knowledge and ministry activism. This way of being does not account for a person’s interior life, specifically the aspect of an internal working model which drives how a person experiences or emotionally relates to God, something known as a ‘‘god image.’’ This article addresses the critical factors that play into how each person develops a representation of God, and how wounded god images function as a ceiling of sorts that keep so many from substantive and deep formation into Christlikeness through the Spirit. After exploring the role a person’s god image plays in the process of spiritual formation, the article will examine how the Spirit is at work in the deepest parts of human persons to open them up to experience the love of God in new, transformative ways.

Hemorrhage accounts for 40-50% of deaths in severe trauma patients. IV administration of TXA within three hours of injury reduces mortality. In this study we show IM TXA is equally efficacious as IV in treating hyperfibrinolysis in an in vivo swine model.

ABSTRACTInternationally, there is recognition that the transition from military service to civilian life is challenged by a military identity. The aim of this study was to present the impact of an occupational military identity on the transition to civilian life from the perspective of former serving Australian Defence Force members. A narrative inquiry methodology was employed to explore the transition experience of the participants who each shared the story of their transition, presenting a narrative for data analysis. This analysis utilised Braun and Clarke’s thematic analysis (2006, 2020), and the a prioritheme of identity. The 12 participant narratives led to the presentation of four themes: 1) Transition and a military identity; 2) Military service and a military identity; 3) Military identity and separation type (voluntary and involuntary); and 4) Enabling transition and the military identity in civilian life. The participants’ narratives highlighted how their occupational participation in military training and culture shaped an identity to challenge transition. Yet, they also highlighted the positive influence of a military identity, offering insights into how best to enable the transition from military service to civilian life.

Organophosphorus chemicals, including chemical warfare agents (CWAs) and insecticides, are acutely toxic materials that warrant capture and degradation. Metal–organic frameworks (MOFs) have emerged as a class of tunable, porous, crystalline materials capable of hydrolytically cleaving, and thus detoxifying, several organophosphorus nerve agents and their simulants. One such MOF is M-MFU-4l (M = metal), a bioinspired azolate framework whose metal node is composed of a variety of divalent first-row transition metals. While Cu-MFU-4l and Zn-MFU-4l are shown to rapidly degrade CWA simulants, Ni-MFU-4l and Co-MFU-4l display drastically lower activities. The lack of reactivity was hypothesized to arise from the strong binding of the phosphate product to the node, which deactivates the catalyst by preventing turnover. No such study has provided detailed insight into this mechanism. Here, we leverage isothermal titration calorimetry (ITC) to monitor the binding of an organophosphorus compound with the M-MFU-4l series to construct a complete thermodynamic profile (Ka, ΔH, ΔS, ΔG) of this interaction. This study further establishes ITC as a viable technique to probe small differences in thermodynamics that result in stark differences in material properties, which may allow for better design of first-row transition metal MOF catalysts for organophosphorus hydrolysis.

The first general enantioselective alkyl-Nozaki–Hiyama–Kishi (NHK) coupling reactions are disclosed herein by employing a Cr-electrocatalytic decarboxylative approach. Using easily accessible aliphatic carboxylic acids (via redox-active esters) as alkyl nucleophile synthons, in combination with aldehydes and enabling additives, chiral secondary alcohols are produced in a good yield with high enantioselectivity under mild reductive electrolysis. This reaction, which cannot be mimicked using stoichiometric metal or organic reductants, tolerates a broad range of functional groups and is successfully applied to dramatically simplify the synthesis of multiple medicinally relevant structures and natural products. Mechanistic studies revealed that this asymmetric alkyl e-NHK reaction was enabled by using catalytic tetrakis(dimethylamino)ethylene, which acts as a key reductive mediator to mediate the electroreduction of the CrIII/chiral ligand complex.

Raised peatlands, or bogs, are gently mounded landforms that are composed entirely of organic matter1–4and store the most carbon per area of any terrestrial ecosystem5. The shapes of bogs are critically important because their domed morphology4,6,7accounts for much of the carbon that bogs store and determines how they will respond to interventions8,9to stop greenhouse gas emissions and fires after anthropogenic drainage10–13. However, a general theory to infer the morphology of bogs is still lacking4,6,7. Here we show that an equation based on the processes universal to bogs explains their morphology across biomes, from Alaska, through the tropics, to New Zealand. In contrast to earlier models of bog morphology that attempted to describe only long-term equilibrium shapes4,6,7and were, therefore, inapplicable to most bogs14–16, our approach makes no such assumption and makes it possible to infer full shapes of bogs from a sample of elevations, such as a single elevation transect. Our findings provide a foundation for quantitative inference about the morphology, hydrology and carbon storage of bogs through Earth’s history, as well as a basis for planning natural climate solutions by rewetting damaged bogs around the world.

Study design: Biomechanical simulation of DVR and pure-moment testing on thoracic spines. Objectives: Characterize load-deformation response of thoracic spines under DVR maneuvers until failure, and compare to pure-moment testing of same spines. Summary of background data: Despite reports of surgical complications, few studies exist on increase in ROM under DVR torque. Biomechanical models predicting increases from surgical releases have consistently used “pure-moments”, a standard established for non-destructive measurement of ROM. Yet, DVR torque is not accurately modeled using pure moments and, moreover, magnitudes of torque applied during DVR maneuvers may be substantially higher than pure-moment testing. Methods: Cadaveric thoracic spines (N= 11) were imaged, then prepared. Polyaxial pedicle screws were implanted at T7–T10 after surgical releases. Bilateral facetectomies and Ponte osteotomies were completed at T10–T11. A custom apparatus, mounted into an 8-dofMTS load frame, was used to attach to pedicle screws, allowing simulation of surgical DVR maneuvers. Motions of vertebrae were measured using optical motion tracking. Torque was increased until rupture of the T10–T11 disc or fracture at the pedicle screw sites at any level. The torque-rotation behavior was compared to its behavior under pure-moment testing performed prior to the DVR maneuver. Results: Under DVR maneuvers, failure of the T10–T11 discs accompanied in most cases by pedicle screw loosening, occurred at 13.7–54.7 Nm torque, increasing axial rotation by 1.4°–8.9°. In contrast, pure-moment testing (4 Nm) increased axial rotation by only 0.0°–0.9°. Conclusions: DVR resulted in substantially greater correction potential increases compared to pure-moment testing even at the same torque. These results suggest increased flexibility obtained by osteotomies and facetectomies is underestimated using pure-moment testing, misrepresenting clinical expectations. The present study is an important and necessary step toward the establishment of a more accurate and ultimately surgically applied model. Level of evidence: III.

The conventional dc-link aluminum electrolytic capacitor bank simply, efficiently, and cost-effectively decouples the instantaneous power mismatch inherent to all single-phase ac–dc power converters. However, the practical realization of the capacitor bank remains largely qualitative and dependent on the opaque performance capabilities of the capacitor technology. This work presents an exhaustive survey of commercial aluminum electrolytic capacitors and defines both quantitative and justly comparative device-level figures-of-merit (FOM). By configuring the relative voltage ripple ratio specification $\alpha$ of the dc bus, these device FOM enable the determination of minimal dc-link capacitor volume, cost, and/or mass. Graphical illustration demonstrates that the set of commercially available yet viable components diminishes as specification $\alpha$ increases; the realized dc-link capacitor bank volume and cost will grow appreciably for ${\alpha >\!10\,{\%}}$ and ${\alpha >\!5\,{\%}}$, respectively.

This article presents a general analytical framework enabling the large-signal characterization of resonant switched-capacitor (ReSC) power converters that accounts for passive component voltage and current ripple, for operation at and above resonance. From this, appropriate phase durations for minimized rms currents are derived, in addition to expressions for total passive component volume using an intuitive peak energy method. An example hardware prototype validates both the derived waveforms and timings—as well as total passive volume—through three comparable hardware configurations, one of which minimizes passive component volume. In addition, the proposed technique formulates analytical expressions for both rms currents and peak blocking voltages, facilitating refined loss estimation and component selection. Subsequent calculation of the large-signal volt-amp switch stress metric allows a more accurately quantified tradeoff between active and passive components compared to prior work, which has not fully accounted for ripple. Four common ReSC topologies are exemplified throughout, with topology-specific parameters documented for reference.

There has been significant progress in the prevention of sudden cardiac death in repaired tetralogy of Fallot. Contemporary cohorts report greater survival attributable to improved surgical techniques, heart failure management, and proactive strategies for risk stratification and management of ventricular arrhythmias including defibrillator implantation and ablation technology. Over the last 25 years, our understanding of predictive risk factors has also improved from invasive and more limited measures to individualized risk prediction scores based on extensive demographic, imaging, electrophysiological, and functional data. Although each of these contemporary scoring systems improves prediction, there are important differences between the study cohorts, included risk factors, and imaging modalities that can significantly affect interpretation and implementation for the individual patient. In addition, accurate phenotyping of disease complexity and anatomic repair substantially modulates this risk and the mechanism of sudden death. Routine implementation of risk stratification within repaired tetralogy of Fallot management is important and directly informs primary prevention defibrillator implantation as well as consideration for proactive invasive strategies including ventricular tachycardia ablation and pulmonary valve replacement. Assessment and risk stratification by a multidisciplinary team of experts in adult congenital heart disease are crucial and critical. Although we have increased understanding, reconciliation of these complex factors for the individual patient remains challenging and often requires careful consideration and discussion with multidisciplinary teams, patients, and their families.

Herein, we have developed a drug-loaded matrix metalloproteinase (MMP)-responsive micellar nanoparticle (NP) intended for minimally invasive intravenous injection during the acute phase of myocardial infarction (MI) and prolonged retention in the heart for small-molecule drug delivery. Peptide-polymer amphiphiles (PPAs) bearing a small-molecule MMP inhibitor (MMPi), PD166793, were synthesized via ring-opening metathesis polymerization (ROMP) and formulated into spherical micelles by transitioning to aqueous solution. The resulting micellar NPs underwent MMP-induced aggregation, demonstrating enzyme responsiveness. Using a rat MI model, we observed that these NPs were capable of successfully extravasating into the infarcted region of the heart where they were retained due to the active, enzyme-mediated targeting, remaining detectable after 1 week post administration without increasing macrophage recruitment. Furthermore, in vitrostudies show that these NPs demonstrated successful drug release following MMP treatment and maintained drug bioactivity as evidenced by comparable MMP inhibition to free MMPi. This work establishes a targeted NP platform for delivering small-molecule therapeutics to the heart after MI, opening possibilities for myocardial infarction treatment.

Geographic atrophy is a leading cause of progressive, irreversible vision loss. The objectives of OAKS and DERBY were to assess the efficacy and safety of pegcetacoplan compared with sham treatment in patients with geographic atrophy.