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The present study focuses on the spin-dependent vibrational properties of HKUST-1, a metal-organic framework with potential applications in gas storage and separation. Employing density functional theory (DFT), we explore the consequences of spin couplings in the copper paddle wheels (as the secondary building units of HKUST-1) on the material's vibrational properties. By systematically screening the impact of the spin state on the phonon bands and densities of states in the various frequency regions, we identify asymmetric -COO- stretching vibrations as being most affected by different types of magnetic couplings. Notably, we also show that the DFT-derived insights can be quantitatively reproduced employing suitably parametrized, state-of-the-art machine-learned classical potentials with root-mean-square deviations from the DFT results between 3 cm -1 and 7 cm -1 . This demonstrates the potential of machine-learned classical force fields for predicting the spin-dependent properties of complex materials, even when explicitly considering spins only for the generation of the reference data used in the force-field parametrization process.

Background: The INFINITY total ankle implant is a widely and successfully used option for total ankle arthroplasty. The purpose of this study is to assess the 2-year survivorship, complication rates, patient-reported outcomes, and radiologic findings of prospectively enrolled patients undergoing a fixed-bearing total ankle arthroplasty (TAA). This study sought to determine if factors such as traditional vs patient-specific instrumentation, preoperative degree of arthritis, deformity, or etiology of arthritis impact surgical or clinical outcomes., Methods: A total of 143 prospectively enrolled patients (148 ankles) underwent TAA with a fixed-bearing total ankle implant between 2017 and 2019 at 9 different institutions by 9 different surgeons. A total of 116 completed 2-year follow-up. Patients were stratified by instrumentation used, degree of preoperative deformity, the Canadian Orthopaedic Foot and Ankle Society (COFAS) grading system, and etiology of arthritis. Outcomes used included implant survivorship and adverse events within 2 years of surgery. Additionally, patient-reported outcomes and radiographs were collected at 6-month, 1-year, and 2-year postoperatively. PROMs used included Ankle Osteoarthritis Score (AOS), Patient-Reported Outcomes Measurement Information System (PROMIS) global health score, the Foot and Ankle Outcome Score (FAOS), and patient satisfaction (rated from excellent to poor)., Results: Implant survivorship at 2 years was 97.79%. There were 17 reoperations (11.5%), with 4 of the implants requiring revision (2.7%). Significant improvements in all PROMs were observed among all subgroups at all postoperative time points without significant variation between subgroups. Patients classified as COFAS type 2 arthritis preoperatively demonstrated significantly more improvement in FAOS Total Symptom Score at the 1- and 2-year measurements than COFAS type 3 patients at both time points., Conclusion: Total ankle arthroplasty with a fixed-bearing implant system is a safe and reliable treatment option for patients with end-stage arthritis regardless of degree of deformity or COFAS grading., Level of Evidence: Level II, prospective cohort study., Competing Interests: Ethical ApprovalEthical approval for this study was obtained from Medical University of South Carolina institutional review board Pro00080181. Declaration of Conflicting InterestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Jesse Doty, MD, reports grants or contracts from any entity; royalties or licenses; consulting fees; and payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events from Stryker. Donald R. Bohay, MD, FACS, reports consulting fees; and payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Stryker. G. Andrew Murphy, MD, Paul T. Fortin, MD, and Anand Vora, MD, report support for the present manuscript from Wright Medical. David A. Friscia, MD, reports support for the present manuscript; consulting fees; payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events; and support for attending meetings and/or travel from Stryker. ICMJE forms for all authors are available online.

Effects of dietary protein quality on insect development (not just growth) are unclear. Dietary amino acid blends matching yolk proteins support reproduction and juvenile development in Drosophila melanogaster. We matched amino acids to vitellogenin and tested development of juvenile male lubber grasshoppers, which do not produce vitellogenin. Last instars were fed classic dry diets with amino acids substituted for proteins. Matching amino acids to vitellogenin allowed molting to adulthood, while an unmatched isonitrogenous diet did not. Health on dry diets was poor, so we developed wet diets with agar, horse feed, and amino acids. Juveniles fed these diets matched to vitellogenin developed comparably to juveniles fed lettuce. However, wet diets with amino acids dissimilar to vitellogenin (low-quality) slowed development but maintained size at adulthood. We observed no compensatory feeding on low-quality diets. Theory suggests accumulation of proteins permits development. To detect a threshold, we started last juvenile instars on high-quality diets, then abruptly switched them to low-qualities diets. When switched to the poor-quality diet at 6d, grasshoppers molted at a similar age (∼17d) to grasshoppers continuously on the high-quality diet. Total hemolymph proteins levels were unaffected by the timing of diet switches. Last, methionine is essential but can be noxious at high levels. Diets with low-quality protein except for methionine slowed growth early but did not alter the time or size at molt. Overall, the feeding threshold is solely due to essential amino acids, and low-quality protein diets slowed development but did not affect adult size., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

We seek to determine the effect of competing intermolecular hydrogen bonds from water on the preferred conformation of 4-aminobutanol (4AB) monomers stabilized by intramolecular hydrogen bonds. Toward this end, the rotational spectrum of the 4-aminobutanol-H 2 O complex was recorded using Fourier transform microwave spectroscopy and fit to the rotational, quadrupole coupling, and centrifugal distortion constants of the Watson S-reduction Hamiltonian. The experimental results are consistent with a 4AB-water complex that preserves the intramolecular hydrogen bond within the 4AB monomer and forms a single intermolecular bond with water acting as a donor. The experimental monomer structure agrees well with the lowest energy conformation calculated at the MP2/6-311++G(d,p) level of theory. Upon complex formation and the introduction of competing intermolecular bonds from water, only small changes in the OH···N intramolecular hydrogen bond and backbone torsional angles of the 4-aminobutanol monomer are observed. Similar small changes were observed for the shorter chain 3-aminopropanol amino alcohol monomer when complexed with water, in contrast to the 2-aminoethanol-H 2 O complex. In the latter, a large change in the backbone torsional angle and a breaking of the intramolecular hydrogen bond were observed. Thus, extending the methylene chain results in an increase in the strength of the intramolecular hydrogen bond in unbranched amino alcohols.

Background: Peroneal tendon displacement (subluxation or dislocation) accompanying an intra-articular calcaneal fracture is often undetected and under-treated. The goals of this study were to determine (1) the prevalence of peroneal tendon displacement accompanying intra-articular calcaneal fractures, (2) the association of tendon displacement with fracture classifications, (3) the association of tendon displacement with heel width, and (4) the rate of missed diagnosis of the tendon displacement on radiographs and computed tomography (CT) scans and the resulting treatment rate., Methods: A retrospective radiographic review of all calcaneal fractures presenting at three institutions from June 30, 2006, to June 30, 2011, was performed. CT imaging of 421 intra-articular calcaneal fractures involving the posterior facet was available for review. The prevalence of peroneal tendon displacement was noted and its associations with fracture classification and heel width were evaluated., Results: Peroneal tendon displacement was identified in 118 (28.0%) of the 421 calcaneal fracture cases. The presence of tendon displacement was significantly associated with joint-depression fractures compared with tongue-type fractures (p < 0.001). Only twelve (10.2%) of the 118 cases of peroneal tendon displacement had been identified in the radiology reports. Although sixty-five (55.1%) of the fractures with tendon displacement had been treated with internal fixation, the tendon displacement was treated surgically in only seven (10.8%) of these cases., Conclusions: Analysis of CT images showed a 28% prevalence of peroneal tendon displacement accompanying intra-articular calcaneal fractures. Surgeons and radiologists are encouraged to consider this association.