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1.
Natl Sci Rev ; 11(8): nwae107, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39007011

RESUMEN

The magnetic correlations at the superconductor/ferromagnet (S/F) interfaces play a crucial role in realizing dissipation-less spin-based logic and memory technologies, such as triplet-supercurrent spin-valves and 'π' Josephson junctions. Here we report the observation of an induced large magnetic moment at high-quality nitride S/F interfaces. Using polarized neutron reflectometry and DC SQUID measurements, we quantitatively determined the magnetization profile of the S/F bilayer and confirmed that the induced magnetic moment in the adjacent superconductor only exists below T C. Interestingly, the direction of the induced moment in the superconductors was unexpectedly parallel to that in the ferromagnet, which contrasts with earlier findings in S/F heterostructures based on metals or oxides. First-principles calculations verified that the unusual interfacial spin texture observed in our study was caused by the Heisenberg direct exchange coupling with constant J∼4.28 meV through d-orbital overlapping and severe charge transfer across the interfaces. Our work establishes an incisive experimental probe for understanding the magnetic proximity behavior at S/F interfaces and provides a prototype epitaxial 'building block' for superconducting spintronics.

2.
Chem Asian J ; : e202400464, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38861115

RESUMEN

As a type of diverse and structurally adjustable metal-oxo clusters, polyoxometalates (POMs) based materials have been extensively applied as a catalysis in various valuable reactions. This review summarized recent progress in the application of POMs-based catalysts for various carbonylation reactions including (1). Carbonylation of olefins, (2). Carbonylation of formaldehyde, (3). Carbonylation of methanol or dimethyl ether, (4). Oxidative carbonylation of methane, (5). Oxidative carbonylation of phenol and (6). Reductive carbonylation of nitrobenzene. A brief perspective on POMs-based catalysts for the carbonylation reactions is proposed.

3.
Chem Asian J ; : e202400467, 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38923814

RESUMEN

3-Methylpyridine holds a pivotal role in organic chemistry as it constitutes a fundamental structure in numerous biologically active compounds. Its significance is underscored by its involvement in synthesizing vitamin B3 and developing pyridine insecticides, garnering considerable attention. Consequently, chemists have dedicated efforts to devising efficient and environmentally friendly methods for its preparation. This review systematically reviews several synthetic routes to 3-methylpyridine, alongside recent advancements, while summarizing its application progress in various organic transformations.

4.
ACS Appl Mater Interfaces ; 16(26): 34386-34392, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38869156

RESUMEN

Highly crystalline and easily feasible topological insulator-superconductor (TI-SC) heterostructures are crucial for the development of practical topological qubit devices. The optimal superconducting layer for TI-SC heterostructures should be highly resilient against external contamination and structurally compatible with TIs. In this study, we provide a solution to this challenge by showcasing the growth of a highly crystalline TI-SC heterostructure using refractory TiN (111) as the superconducting layer. This approach can eliminate the need for in situ cleavage or growth. More importantly, the TiN surface shows high resilience against contaminations during air exposure, as demonstrated by the successful recyclable growth of Bi2Se3. Our findings indicate that TI-SC heterostructures based on nitride films are compatible with device fabrication techniques, paving the way to the realization of practical topological qubit devices in the future.

5.
Nano Lett ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38781119

RESUMEN

Although transition-metal nitrides have been widely applied for several decades, experimental investigations of their high-resolution electronic band structures are rare due to the lack of high-quality single-crystalline samples. Here, we report on the first momentum-resolved electronic band structures of titanium nitride (TiN) films, which are remarkable nitride superconductors. The measurements of the crystal structures and electrical transport properties confirmed the high quality of these films. More importantly, from a combination of high-resolution angle-resolved photoelectron spectroscopy and first-principles calculations, the extracted Coulomb interaction strength of TiN films can be as large as 8.5 eV, whereas resonant photoemission spectroscopy yields a value of 6.26 eV. These large values of Coulomb interaction strength indicate that superconducting TiN is a strongly correlated system. Our results uncover the unexpected electronic correlations in transition-metal nitrides, potentially providing a perspective not only to understand their emergent quantum states but also to develop their applications in quantum devices.

6.
Knee Surg Sports Traumatol Arthrosc ; 32(7): 1650-1659, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38651601

RESUMEN

PURPOSE: To explore the relationship between preoperative J-sign grading and structural bone abnormalities in patients with recurrent patellar dislocation (RPD). METHODS: A retrospective study was conducted on RPD patients over 5 years. Patients were categorised based on J-sign grade into low (J- and J1+), moderate (J2+) and high groups (J3+). Trochlear dysplasia (TD) and osseous structures (femoral anteversion angle [FAA], knee torsion, tibial tuberosity-trochlear groove [TT-TG] distance, Caton-Deschamps index) were assessed and grouped according to risk factor thresholds. The χ2 test was used to compare composition ratio differences of structural bone abnormalities among the groups. RESULTS: A total of 256 patients were included, with 206 (80.5%) females. The distribution of J-sign grade was as follows: 89 knees (34.8%) of low grade, 86 moderate (33.6%) and 81 high (31.6%). Among the five structural bone abnormalities, TD was the most common with a prevalence of 78.5%, followed by increased TT-TG at 47.4%. Excessive tibiofemoral rotation had the lowest occurrence at 28.9%. There were 173 (67.6%) patients who had two or more abnormalities, while 45 (17.6%) had four to five bony abnormalities. Among patients with any bony abnormality, the proportion of high-grade J-sign surpassed 40%. Patients with moderate and high-grade J-sign had more increased FAA and more pronounced patella alta (all p < 0.001). The proportion of excessive knee torsion and TD increased with increasing each J-sign grade, with the more notable tendency in knee torsion (high vs. moderate vs. low-grade: 61% vs. 22% vs 7%, p < 0.001). Furthermore, the higher J-sign grade was also associated with more combined bony abnormalities (p < 0.001). In the high-grade J-sign group, 90.2% of the knees had two or more bony risk factors and 40.7% had four or more, which were significantly higher than the moderate and low-grade J-sign groups (40.7% vs. 11.6% vs. 2.2%, p < 0.001). CONCLUSION: In patients with a high-grade J-sign, over 90% of the lower limbs had two or more structural bone risk factors, and more than 40% had four or more. These proportions were significantly higher compared to knees with low-grade and moderate J-sign. In clinical practice, when treating high-grade patellar mal-tracking, it is important to focus on and correct these strongly correlated abnormal bone structures. LEVEL OF EVIDENCE: Level III.


Asunto(s)
Fémur , Luxación de la Rótula , Recurrencia , Humanos , Femenino , Masculino , Luxación de la Rótula/diagnóstico por imagen , Estudios Retrospectivos , Adulto , Adolescente , Fémur/anomalías , Fémur/diagnóstico por imagen , Adulto Joven , Tibia/anomalías , Tibia/diagnóstico por imagen , Factores de Riesgo , Rótula/anomalías , Rótula/diagnóstico por imagen
7.
Discov Nano ; 19(1): 42, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38467967

RESUMEN

Vanadium nitride (VN) is a transition-metal nitride with remarkable properties that have prompted extensive experimental and theoretical investigations in recent years. However, there is a current paucity of experimental research investigating the temperature-dependent electronic structure of single-crystalline VN. In this study, high-quality VN(111) films were successfully synthesized on α -Al 2 O 3 (0001) substrates using magnetron sputtering. The crystal and electronic structures of the VN films were characterized by a combination of high-resolution X-ray diffraction, low-energy electron diffraction, resonant soft X-ray absorption spectroscopy, and ultraviolet photoelectron spectroscopy. The electrical transport measurements indicate that the superconducting critical temperature of the VN films is around 8.1 K. Intriguingly, the temperature-dependent photoelectron spectroscopy measurements demonstrate a weak temperature dependence in the electronic structure of the VN films, which is significant for understanding the ground state of VN compounds.

8.
Knee Surg Sports Traumatol Arthrosc ; 32(1): 151-166, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38226710

RESUMEN

PURPOSE: The purpose of this study is to systematically review and quantitatively analyse the clinical outcomes of combined derotational distal femoral osteotomy (D-DFO) and medial patellofemoral ligament reconstruction (MPFL-R) in the treatment of recurrent patellar dislocation (RPD) with increased femoral anteversion angle (FAA). METHODS: This study was performed in line with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and AMSTAR (Assessing the Methodological Quality Of Systematic Reviews) Guidelines. PubMed, Embase, Web of Science and Cochrane Library databases were searched to identify studies reporting clinical outcomes of combined D-DFO and MPFL-R in RPD patients with increased FAA. Data on patient-reported outcome measures, radiological parameters, patellar tracking as revealed by J-sign and complications were extracted based on the inclusion criteria. The Methodological Index for Non-Randomized Study score was used for quality assessment. Review Manager and R statistical software were used to perform the statistical analysis. RESULTS: Eleven studies with a total of 569 knees in 553 patients were included. Patients were predominantly female (79%). The weighted mean of FAA decreased from 33.6° to 13.0° (weighted mean difference = 20.59; p < 0.00001) after the combined procedure. Significant improvements (p < 0.00001) were identified in the Lysholm score (weighted mean: 55.5 vs. 80.4), International Knee Documentation Committee (IKDC) score (weighted mean: 52.8 vs. 78.6) and Kujala score (weighted mean: 54.5 vs. 80.6). The incidence of residual J-sign ranged from 14.3% to 38.3% with an overall pooled rate of 28.2% (95% confidence interval = 22.8%-33.6%). The overall redislocation rate was 1.1%. No patients experienced surgical site infection or bone nonunion. Two studies compared the clinical outcomes of MPFL-R with and without D-DFO. Compared with isolated MPFL-R, the combined procedure yielded a better Lysholm score (weighted mean: 84.9 vs. 79.3, p < 0.0001), IKDC score (weighted mean: 84.1 vs. 79.9, p = 0.001), Kujala score (weighted mean: 84.3 vs. 79.4, p < 0.0001) and a lower residual J-sign rate (26/97 [26.8%] vs. 44/105 [41.9%], p = 0.02), respectively. CONCLUSION: The combination of D-DFO and MPFL-R led to improved clinical outcomes and a low redislocation rate in patients with RPD and increased FAA. Additional D-DFO can achieve more favourable results in subjective function and patellar tracking than isolated MPFL-R in the setting of excessive FAA. LEVEL OF EVIDENCE: Level IV.


Asunto(s)
Luxaciones Articulares , Inestabilidad de la Articulación , Luxación de la Rótula , Ligamento Rotuliano , Articulación Patelofemoral , Humanos , Femenino , Masculino , Luxación de la Rótula/cirugía , Articulación Patelofemoral/cirugía , Fémur/cirugía , Osteotomía/métodos , Ligamentos Articulares/cirugía , Inestabilidad de la Articulación/cirugía , Ligamento Rotuliano/cirugía
9.
Knee Surg Sports Traumatol Arthrosc ; 31(11): 5162-5170, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37789216

RESUMEN

PURPOSE: To compare clinical outcome between recurrent patellar dislocation (RPD) with or without actual tibial tubercle lateralisation (TTL) after medial patellofemoral ligament reconstruction (MPFL-R) combined with tibial tubercle transfer. METHODS: From 2015 to 2018, a total of 172 knees with RPD and a tibial tubercle-trochlear groove (TT-TG) distance of > 20 mm were treated with MPFL-R combined with tibial tubercle transfer. Patients were divided into the lateralisation group (TT-PCL > 24 mm, n = 74) and the nonlateralisation group (TT-PCL ≤ 24 mm, n = 60) based on the presence or absence of actual TTL (TT-PCL > 24 mm). Clinical outcomes were assessed postoperatively at a minimum of 2 years. Second-look arthroscopic evaluations were available for 84 knees to assess cartilage damage. RESULTS: A total of 134 knees with a median follow-up time of 32 months were included. Tibiofemoral rotation (TFR) was significantly higher in the nonlateralisation group than in the lateralisation group (15.4° vs. 9.4°, P < 0.001). At the final follow-up, the nonlateralisation group had significantly lower Kujala (78.2 vs. 86.4, P = 0.001) and Lysholm (80.3 vs. 88.2, P = 0.003) scores than the lateralisation group. At the time of the second-look arthroscopic assessment, 38.9% of the patients in the nonlateralisation group showed cartilage worsening in the medial patellar facet that was significantly higher than that in the lateralisation group (38.9% vs. 12.5%, P = 0.015). CONCLUSION: Patients with RPD and an increased TT-TG distance of > 20 mm but without actual tibial tubercle lateralisation benefit less from tibial tubercle transfer than patients with actual tibial tubercle lateralisation, which may be related to the significantly higher tibiofemoral rotation angle of the former. LEVEL OF EVIDENCE: III.


Asunto(s)
Luxaciones Articulares , Inestabilidad de la Articulación , Luxación de la Rótula , Articulación Patelofemoral , Humanos , Luxación de la Rótula/cirugía , Articulación Patelofemoral/cirugía , Rotación , Tibia/cirugía , Osteotomía , Estudios Retrospectivos , Inestabilidad de la Articulación/etiología , Inestabilidad de la Articulación/cirugía
10.
JACS Au ; 3(8): 2166-2173, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37654585

RESUMEN

Numerous chemical transformations require two or more catalytically active sites that act in a concerted manner; nevertheless, designing heterogeneous catalysts with such multiple functionalities remains an overwhelming challenge. Herein, it is shown that by the integration of acidic flexible polymers and Pd-metallated covalent organic framework (COF) hosts, the merits of both catalytically active sites can be utilized to realize heterogeneous synergistic catalysis that are active in the conversion of nitrobenzenes to carbamates via reductive carbonylation. The concentrated catalytically active species in the nanospace force two catalytic components into proximity, thereby enhancing the cooperativity between the acidic species and Pd species to facilitate synergistic catalysis. The resulting host-guest assemblies constitute more efficient systems than the corresponding physical mixtures and the homogeneous counterparts. Furthermore, this system enables easy access to a family of important derivatives such as herbicides and polyurethane monomers and can be integrated with other COFs, showing promising results. This study utilizes host-guest assembly as a versatile tool for the fabrication of multifunctional catalysts with enhanced cooperativity between different catalytic species.

11.
Int J Food Microbiol ; 403: 110305, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37421839

RESUMEN

Salmonella is a major foodborne pathogen that poses a substantial risk to food safety and public health. This study aimed to assess the prevalence, antibiotic susceptibility, and genomic features of Salmonella isolates recovered from 600 retail meat samples (300 pork, 150 chicken and 150 beef) from August 2018 to October 2019 in Shaanxi, China. Overall, 40 (6.67 %) of 600 samples were positive to Salmonella, with the highest prevalence in chicken (21.33 %, 32/150), followed in pork (2.67 %, 8/300), while no Salmonella was detected in beef. A total of 10 serotypes and 11 sequence types (STs) were detected in 40 Salmonella isolates, with the most common being ST198 S. Kentucky (n = 15), ST13 S. Agona (n = 6), and ST17 S. Indiana (n = 5). Resistance was most commonly found to tetracycline (82.50 %), followed by to ampicillin (77.50 %), nalidixic acid (70.00 %), kanamycin (57.50 %), ceftriaxone (55.00 %), cefotaxime (52.50 %), cefoperazone (52.50 %), chloramphenicol (50.00 %), levofloxacin (57.50 %), cefotaxime (52.50 %), kanamycin (52.50 %), chloramphenicol (50.00 %), ciprofloxacin (50.00 %), and levofloxacin (50.00 %). All ST198 S. Kentucky isolates showed multi-drug resistance (MDR; ≥3 antimicrobial categories) pattern. Genomic analysis showed 56 distinct antibiotic resistance genes (ARGs) and 6 target gene mutations of quinolone resistance determining regions (QRDRs) in 40 Salmonella isolates, among which, the most prevalent ARG types were related to aminoglycosides and ß-lactams resistance, and the most frequent mutation in QRDRs was GyrA (S83F) (47.5 %). The number of ARGs in Salmonella isolates showed a significant positive correlation with the numbers of insert sequences (ISs) and plasmid replicons. Taken together, our findings indicated retail chickens were seriously contaminated, while pork and beef are rarely contaminated by Salmonella. Antibiotic resistance determinants and genetic relationships of the isolates provide crucial data for food safety and public health safeguarding.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple , Levofloxacino , Bovinos , Animales , Prevalencia , Farmacorresistencia Bacteriana Múltiple/genética , Pollos , Salmonella , Antibacterianos/farmacología , Carne , Cefotaxima , China , Cloranfenicol , Kanamicina , Genómica , Pruebas de Sensibilidad Microbiana
12.
Polymers (Basel) ; 15(11)2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37299308

RESUMEN

An eco-friendly medium-density fiberboard (MDF) was prepared using vanillin (V) crosslinked chitosan (CS) adhesive through a hot-pressing process. The cross-linking mechanism and the effect of different proportions of added chitosan/vanillin on the mechanical properties and dimensional stability of MDF were investigated. The results showed that vanillin and chitosan are crosslinked to form a three-dimensional network structure due to the Schiff base reaction between the aldehyde group of vanillin and the amino group of chitosan. At the same time, when the mass ratio between vanillin/chitosan was 2:1, MDF obtained the best mechanical properties, the maximum modulus of rupture (MOR) of 20.64 MPa, the mean modulus of elasticity (MOE) of 3005 MPa, the mean internal bonding (IB) of 0.86 MPa, and the mean thickness swelling (TS) of 14.7%. Therefore, the MDF bonded with V-crosslinked CS can be a promising candidate for environmentally-friendly wood-based panels.

13.
Nano Lett ; 23(9): 3879-3886, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37115190

RESUMEN

The fabrication of flexible single-crystalline plasmonic or photonic components in a scalable way is fundamentally important to flexible electronic and photonic devices with high speed, high energy efficiency, and high reliability. However, it remains a challenge. Here, we have successfully synthesized flexible single-crystalline optical hyperbolic metamaterials by directly depositing refractory nitride superlattices on flexible fluorophlogopite-mica substrates with magnetron sputtering. Interestingly, these flexible hyperbolic metamaterials show dual-band hyperbolic dispersion of dielectric constants with small dielectric losses and high figures of merit in the visible to near-infrared ranges. More importantly, the optical properties of these nitride-based flexible hyperbolic metamaterials show remarkable stability during 1000 °C heating or after being bent 1000 times. Therefore, the strategy developed in this work offers an easy and scalable route for fabricating flexible, high-performance, and refractory plasmonic or photonic components, which can significantly expand the applications of current electronic and photonic devices.

14.
ACS Appl Mater Interfaces ; 15(8): 10868-10876, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36794989

RESUMEN

Incorporating emerging ultrawide bandgap semiconductors with a metal-semiconductor-metal (MSM) architecture is highly desired for deep-ultraviolet (DUV) photodetection. However, synthesis-induced defects in semiconductors complicate the rational design of MSM DUV photodetectors due to their dual role as carrier donors and trap centers, leading to a commonly observed trade-off between responsivity and response time. Here, we demonstrate a simultaneous improvement of these two parameters in ε-Ga2O3 MSM photodetectors by establishing a low-defect diffusion barrier for directional carrier transport. Specifically, using a micrometer thickness far exceeding its effective light absorption depth, the ε-Ga2O3 MSM photodetector achieves over 18-fold enhancement of responsivity and simultaneous reduction of the response time, which exhibits a state-of-the-art photo-to-dark current ratio near 108, a superior responsivity of >1300 A/W, an ultrahigh detectivity of >1016 Jones, and a decay time of 123 ms. Combined depth-profile spectroscopic and microscopic analysis reveals the existence of a broad defective region near the lattice-mismatched interface followed by a more defect-free dark region, while the latter one serves as a diffusion barrier to assist frontward carrier transport for substantially enhancing the photodetector performance. This work reveals the critical role of the semiconductor defect profile in tuning carrier transport for fabricating high-performance MSM DUV photodetectors.

15.
Am J Sports Med ; 51(4): 968-976, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36779576

RESUMEN

BACKGROUND: Anterior tibial subluxation (ATS) of the lateral compartment entails a pathological tibiofemoral alignment in knees with anterior cruciate ligament (ACL) injury. Causes of increased ATS after an acute ACL injury are not clear, but soft tissue abnormalities and bony variations of the knee are potential causes. PURPOSE: To determine whether increased ATS of the lateral compartment in knees with acute ACL injury is associated with (1) anterolateral ligament (ALL) status and (2) inherent anatomy of the lateral femoral condyle (LFC) and lateral tibial plateau (LTP). STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A total of 337 patients with clinically diagnosed ACL injuries treated between September 2019 and August 2021 were retrospectively reviewed, and 119 patients with acute ACL injury were included. Of them, 79 patients with impaired ALL (ALL injury group) and 40 patients with intact ALL (ALL intact group) were identified based on magnetic resonance imaging (MRI). The ATS of the lateral compartment measured on MRI was compared between the 2 groups. The bony anatomy of knees, quantified by the LFC length, LFC height, LTP length, and LTP slope, was also evaluated on MRI and correlated with the ATS with partial correlation coefficients. Multivariate linear regression was used to identify the independent predictors of increased ATS. RESULTS: The ATS of the lateral compartment in the ALL injury group was significantly larger than that in the ALL intact group (6.3 mm vs 4.0 mm, respectively; P = .001). In all included patients, the presence of ALL injuries independently predicted a mean increase in ATS of 1.8 mm (P = .003). In the ALL injury group, ATS was significantly correlated with LFC length (r = 0.463; P < .001), LFC height (r = -0.415; P < .001), and LTP slope (r = 0.453; P < .001); further, a 1-mm increase in LFC length, 1-mm decrease in LFC height, and 1° increase in LTP slope independently predicted a mean increase in ATS of 0.7 mm (P < .001), 0.6 mm (P < .001), and 0.5 mm (P < .001), respectively. In the ALL intact group, there was no significant correlation between ATS and any bony parameter. CONCLUSION: An impaired ALL increased the ATS of the lateral compartment after acute ACL injuries. In patients with combined ALL injuries, a flatter LFC and a steeper LTP in the sagittal plane were predictors of a further increase in ATS.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Luxaciones Articulares , Humanos , Lesiones del Ligamento Cruzado Anterior/diagnóstico por imagen , Lesiones del Ligamento Cruzado Anterior/cirugía , Lesiones del Ligamento Cruzado Anterior/complicaciones , Estudios Retrospectivos , Estudios de Cohortes , Estudios Transversales , Reconstrucción del Ligamento Cruzado Anterior/efectos adversos , Articulación de la Rodilla/cirugía , Tibia/cirugía , Ligamento Cruzado Anterior/cirugía , Luxaciones Articulares/cirugía , Imagen por Resonancia Magnética
16.
Adv Sci (Weinh) ; 10(8): e2206203, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36703616

RESUMEN

The anomalous Hall effect (AHE) is a quantum coherent transport phenomenon that conventionally vanishes at elevated temperatures because of thermal dephasing. Therefore, it is puzzling that the AHE can survive in heavy metal (HM)/antiferromagnetic (AFM) insulator (AFMI) heterostructures at high temperatures yet disappears at low temperatures. In this paper, an unconventional high-temperature AHE in HM/AFMI is observed only around the Néel temperature of AFM, with large anomalous Hall resistivity up to 40 nΩ cm is reported. This mechanism is attributed to the emergence of a noncollinear AFM spin texture with a non-zero net topological charge. Atomistic spin dynamics simulation shows that such a unique spin texture can be stabilized by the subtle interplay among the collinear AFM exchange coupling, interfacial Dyzaloshinski-Moriya interaction, thermal fluctuation, and bias magnetic field.

17.
Am J Sports Med ; 51(3): 663-671, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36661484

RESUMEN

BACKGROUND: Derotational distal femoral osteotomy (DDFO) has been used to treat patients with recurrent patellar dislocation (RPD) with increased femoral anteversion. However, no study has reported second-look arthroscopic findings in the patellofemoral joint after DDFO. PURPOSE: To report clinical and second-look arthroscopic outcomes for DDFO with combined medial patellofemoral ligament reconstruction (MPFL-R) in treating RPD with increased femoral anteversion. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: From 2015 to 2019, 131 consecutive patients (144 knees) with RPD were treated with combined MPFL-R and DDFO. Patients with a femoral anteversion angle >30° and a minimum 2-year clinical follow-up period were included in the study. Three-dimensional computed tomography was performed to evaluate rotational deformities of the lower leg. Radiographic parameters presenting bony abnormalities associated with RPD were measured. Second-look arthroscopic evaluations were available for 86 knees to assess patellar tracking and chondral lesion changes. Moreover, clinical and radiologic outcomes were assessed pre- and postoperatively at a minimum 2 years. RESULTS: A total of 102 knees in 92 patients were included in the present study with a mean clinical follow-up of 4.1 years (range, 2.0-5.6 years). Mean ± SD femoral anteversion changed significantly from 34.7°± 7.5° preoperatively to 11.3°± 0.2° postoperatively (P < .001), and mean tibial tubercle-trochlear groove distance decreased significantly from 19.6 ± 3.5 mm preoperatively to 17.4 ± 3.2 mm postoperatively (P < .001). In the majority of knees, at the time of second-look arthroscopic assessment, chondral lesion status remained unchanged at the lateral patellar facet (96%) and trochlear groove (95%); in contrast, chondral damage at the medial patellar facet was aggravated in 9 cases (10%). All functional scores (Tegner, Lysholm, visual analog scale, and Kujala scores) improved significantly at final follow-up. None of the patients experienced redislocation or subluxation after surgery. CONCLUSION: Chondral lesions in the patellofemoral joint remained unchanged in the majority of cases in second-look arthroscopy after combined MPFL-R and DDFO. Moreover, high-grade trochlear dysplasia and arthroscopic residual patellar maltracking might be associated with cartilaginous deterioration at the medial patellar facet after surgery.


Asunto(s)
Luxaciones Articulares , Luxación de la Rótula , Articulación Patelofemoral , Humanos , Luxación de la Rótula/diagnóstico por imagen , Luxación de la Rótula/cirugía , Estudios de Seguimiento , Estudios Retrospectivos , Articulación Patelofemoral/diagnóstico por imagen , Articulación Patelofemoral/cirugía , Ligamentos Articulares/cirugía , Osteotomía/métodos
18.
J Org Chem ; 88(8): 5044-5051, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-36511368

RESUMEN

Ionic liquids (ILs) have been widely used in transition metal-catalyzed processes, but the precise behavior of ILs and catalysts in these reactions is unknown. Herein, the role of ILs and the interaction pattern between Shvo's catalyst and ILs have been revealed with characterization by 1H NMR and crystallography based on the catalytic hydrogenation of CO2. ILs promote the dissociation of Shvo's catalyst and enhance the rate of production of CO. The CO that is produced is subsequently used in the tandem hydroformylation-reduction of alkenes to produce valuable alcohols. In the absence of ILs, formamides can be obtained by N-formylation of most primary or secondary amines.

19.
Open Life Sci ; 17(1): 1579-1590, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36518886

RESUMEN

RUNX3 is a transcription factor and tumor suppressor that is silenced or inactivated in diverse tumors. The effect of RUNX3 on the epithelial-mesenchymal transition in clear-cell renal cell carcinoma (CCRCC) remains unclear. We determined the expression of RUNX3 and E-cadherin in tumor tissues and adjacent normal tissues of 30 CCRCC patients; established cultured CCRCC cells with the overexpression of RUNX3; and examined the in vivo tumorigenic function of RUNX3 in a nude mouse xenograft model of CCRCC. RUNX3 and E-cadherin were downregulated in human CCRCC samples. Cell lines with RUNX3 overexpression had reduced cell proliferation, invasion, and migration, a prolonged cell cycle, increased apoptosis, and increased expression of E-cadherin. In the nude mouse xenograft model of CCRCC, tumors with the overexpression of RUNX3 had smaller volumes and weights and had increased expression of E-cadherin. In conclusion, RUNX3 overexpression increased the level of E-cadherin and inhibited the proliferation, invasion, and migration of CCRCC in vitro and in vivo. RUNX3 has potential use as a biomarker for prognostic monitoring of CCRCC and as a therapeutic target for the treatment of this cancer.

20.
Orthop J Sports Med ; 10(12): 23259671221138854, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36532153

RESUMEN

Background: The tibiofemoral rotation angle has been found to be higher in patients with recurrent patellar dislocations (RPDs) than in healthy people; however, little is known about the clinical significance of this finding. Purpose: To determine whether an increased tibiofemoral rotation angle is associated with graft failure after primary medial patellofemoral ligament reconstruction (MPFL-R) and to investigate the role of the tibiofemoral rotation angle in predicting MPFL-R failure in patients with RPDs. Study Design: Case-control study; Level of evidence, 3. Methods: We retrospectively analyzed the records of 632 consecutive patients with clinically diagnosed RPDs from 2011 to 2018. Postoperative stress radiography of the patellofemoral joint was performed to identify whether the graft failed. After a review, 33 patients who showed MPFL-R failure were allocated to the failure group. They were matched 1:2 to 66 participants who underwent successful MPFL-R (control group). The cutoff value and area under the curve (AUC) of the tibiofemoral rotation angle for predicting graft failure after primary MPFL-R were determined, and the risk factors for MPFL-R failure were assessed by multivariate logistic regression analysis. Results: The tibiofemoral rotation angle was significantly higher in the failure group than in the control group (16.4° ± 5.6° vs 6.4° ± 4.5°, respectively; P < .001). The cutoff value of the tibiofemoral rotation angle for predicting graft failure was 12.3° (sensitivity, 81.8%; specificity, 89.4%; AUC, 0.920). Overall, 3 risk factors for MPFL-R failure were determined: excessive tibiofemoral rotation (≥12.3°) (odds ratio [OR], 13.159 [95% CI, 2.469-70.139]; P = .003), a preoperative high-grade J-sign (OR, 7.674 [95% CI, 1.232-47.809]; P = .029), and a femoral tunnel malposition (OR, 6.976 [95% CI, 1.077-45.187]; P = .042). Conclusion: In this study, excessive tibiofemoral rotation, a preoperative high-grade J-sign, and a femoral tunnel malposition were identified as risk factors for graft failure after primary MPFL-R in patients with RPDs. More importantly, excessive tibiofemoral rotation ( ≥ 12.3°) may predict the failure of primary MPFL-R, which can help surgeons easily identify high-risk patients of MPFL-R failure before surgery.

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