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1.
Angew Chem Int Ed Engl ; 63(17): e202401996, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38445364

RESUMEN

Metal-organic frameworks (MOFs) show wide application as the cathode of aqueous zinc-ion batteries (AZIBs) in the future owning to their high porosity, diverse structures, abundant species, and controllable morphology. However, the low energy density and poor cycling stability hinder the feasibility in practical application. Herein, an innovative strategy of organic/inorganic double electroactive sites is proposed and demonstrated to obtain extra capacity and enhance the energy density in a manganese-based metal-organic framework (Mn-MOF-74). Simultaneously, its energy storage mechanism is systematically investigated. Moreover, profiting from the coordination effect, the Mn-MOF-74 features with stable structure in ZnSO4 electrolyte. Therefore, the Zn/Mn-MOF-74 batteries exhibit a high energy density and superior cycling stability. This work aids in the future development of MOFs in AZIBs.

2.
Child Abuse Negl ; 151: 106723, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38461709

RESUMEN

BACKGROUND: Childhood psychological maltreatment is a risk factor for social anxiety in adulthood. Parent-child separation, as one of the most serious adversities in early life, may exacerbate the risk of psychological maltreatment and influence the interactions between childhood psychological maltreatment and biological sensitivity to stress in relation to social anxiety. However, there has been a dearth of work on this issue. OBJECTIVE: This study investigated the interactive effects between childhood psychological maltreatment and parasympathetic nervous system (PNS) activity on social anxiety in college students by comparing those who experienced parent-child separation versus those who did not. Potential sex differences in the aforementioned associations were tested as an exploratory aim. PARTICIPANTS AND SETTING: Data were obtained from 264 college students (Mage = 18.45 years, SD = 0.69), including 156 students who experienced parent-child separation and 108 students without this experience. METHODS: Participants completed measures of childhood psychological maltreatment and social anxiety and reported their parent-child separation experience. The data of PNS activity, measured by respiratory sinus arrhythmia (RSA) reactivity, were obtained during the Trier Social Stress Test (TSST) in the lab. RESULTS: Childhood psychological maltreatment was positively associated with college students' social anxiety. RSA reactivity moderated the relationship between childhood psychological maltreatment and college students' social anxiety, and the moderating role of RSA reactivity varied with parent-child separation experience and sex. CONCLUSIONS: Parent-child separation experience influenced the biosocial interactions between childhood psychological maltreatment and PNS activity in relation to individuals' social anxiety, and this effect persisted in adulthood.


Asunto(s)
Maltrato a los Niños , Arritmia Sinusal Respiratoria , Humanos , Masculino , Femenino , Adolescente , Niño , Estudiantes/psicología , Sistema Nervioso Parasimpático/fisiología , Arritmia Sinusal Respiratoria/fisiología , Relaciones Padres-Hijo , Ansiedad/epidemiología , Maltrato a los Niños/psicología
3.
J Adolesc ; 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509447

RESUMEN

INTRODUCTION: Left-behind adolescents are vulnerable to depressive symptoms under the context of parent-adolescent separation. However, limited knowledge is available regarding left-behind adolescents' depression trajectory and the protective resources against it. The aim of this longitudinal study was to investigate the depression trajectory and its association with parent-adolescent separation (left-behind status, age of separation and duration of separation) and parent-adolescent cohesion (father-adolescent cohesion, mother-adolescent cohesion) among left-behind adolescents. METHODS: The participants were 1,107 left-behind adolescents (Mage = 13.23 ± 0.86 years at T1; 45.17% girls; 38.48% both-parent migrant adolescents, 61.52% father-only migrant adolescents) from two rural areas of Shandong Province in China, who were participated in assessment at three time points with 6 months apart from November 2014 to November 2015. RESULTS: The results indicated that the trajectory of left-behind adolescents' depression symptoms showed a decreasing trend. Both-parent migrant adolescents reported a higher initial level of depressive symptoms than father-only migrant adolescents. Duration of separation positively predicted the initial level of left-behind adolescents' depressive symptoms. Mother-adolescent cohesion negatively predicted the initial level and positively predicted the change rate of left-behind adolescents' depressive symptoms. Moreover, mother-adolescent and father-adolescent cohesion buffered the negative effect of parent-adolescent separation on the initial level of left-behind adolescents' depressive symptoms. CONCLUSIONS: These findings highlight the protective role of parent-adolescent cohesion for left-behind adolescents, having important implications for interventions targeted toward mitigating the detrimental influence of parent-adolescent separation on left-behind adolescents' depression trajectory.

4.
Int J Pharm ; 651: 123778, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38181990

RESUMEN

To identify a replacement strategy for bronchial thermoplasty (BT) with non-invasive and free-of-severe side effect is urgently needed in the clinic for severe asthma treatment. In this study, PLGA-PEG@ICG@TRPV1 pAb (PIT) photothermal nanoparticles targeting bronchial TRPV1 were designed for photothermal therapy (PTT) against severe murine asthma induced by ovalbumin and lipopolysaccharide. PIT was formulated with a polyethylene glycol (PEG)-grafted poly (lactic-co-glycolic) acid (PLGA) coating as a skeleton structure to encapsulate indocyanine green (ICG) and was conjugated to the polyclonal antibody against transient receptor potential vanilloid 1 (TRPV1 pAb). The results revealed that PIT held good druggability due to its electronegativity and small diameter. PIT demonstrated great photothermal effects both in vivo and in vitro and exhibited good ability to target TRPV1 in vitro because of its selective cell uptake and specific cell toxicity toward TRPV1-overexpressing cells. The PIT treatment effectively reduced asthma symptoms in mice. This is evident from improvements in expiratory airflow limitation, significant decreases in inflammatory cell infiltration in the airways, and increases in goblet cell and columnar epithelial cell proliferation. In conclusion, PIT alleviates severe murine asthma symptoms through a combination of TRPV1 targeting and photothermal effects.


Asunto(s)
Antineoplásicos , Asma , Nanopartículas , Animales , Ratones , Verde de Indocianina , Fototerapia/métodos , Ovalbúmina , Lipopolisacáridos , Nanopartículas/química , Polietilenglicoles/química , Asma/tratamiento farmacológico , Línea Celular Tumoral , Canales Catiónicos TRPV
5.
J Phys Chem B ; 128(3): 812-823, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38193806

RESUMEN

As fourth-generation refrigerants with great development prospects, hydrofluoroolefins (HFOs) can be mixed with other refrigerants, such as carbon dioxide (CO2), to form refrigerant mixtures with low global warming potential (GWP) and zero ozone depleting potential (ODP) while retaining the advantages of each component. Refrigerants can work together to achieve complementary benefits. Combinations of CO2 and HFOs can strengthen the thermodynamic properties of CO2 while inhibiting the flammability of HFOs. At present, relatively few studies have been conducted on the CO2 + 3,3,3-trifluoropropene (R1243zf) mixture. Besides experimental approaches, molecular simulation has grown in importance as a way to determine thermodynamic and transport properties in recent years. In this study, the Gibbs Ensemble Monte Carlo (GEMC) method was used to simulate the vapor-liquid equilibrium (VLE) properties of the CO2 + R1243zf binary mixture in the temperature range of 273.15 to 313.15 K, in which the three-site rigid TraPPE force field and a fully flexible transferable all-atom force field were selected to describe CO2 and R1243zf, respectively. By comparing the GEMC simulation results with the experimental data, it was found that the average deviation of pressure is 2.33%, the average deviation of liquid phase molar fraction Δx is 0.0099, and the mean deviation of gaseous phase molar fraction Δy is 0.0204. The simulation results accord well with the experimental data and the fitting data of the correlation model in the literature, indicating that the molecular models used for CO2 and R1243zf can reliably predict the VLE properties. Finally, the critical parameters of the mixture at a temperature of 313.15 K were predicted, and the radial distribution functions (RDFs) of pure R1243zf and the mixture at 273.15 K and 3.5 MPa were calculated and analyzed by molecular dynamics (MD) simulation.

6.
IEEE Trans Biomed Eng ; 71(3): 1010-1021, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37856261

RESUMEN

OBJECTIVE: The precise alignment of full and partial 3D point sets is a crucial technique in computer-aided orthopedic surgery, but remains a significant challenge. This registration process is complicated by the partial overlap between the full and partial 3D point sets, as well as the susceptibility of 3D point sets to noise interference and poor initialization conditions. METHODS: To address these issues, we propose a novel full-to-partial registration framework for computer-aided orthopedic surgery that utilizes reinforcement learning. Our proposed framework is both generalized and robust, effectively handling the challenges of noise, poor initialization, and partial overlap. Moreover, this framework demonstrates exceptional generalization capabilities for various bones, including the pelvis, femurs, and tibias. RESULTS: Extensive experimentation on several bone datasets has demonstrated that the proposed method achieves a superior C.D. error of 8.211 e-05 and our method consistently outperforms state-of-the-art registration techniques. CONCLUSION AND SIGNIFICANCE: Hence, our proposed method is capable of achieving precise bone alignments for computer-aided orthopedic surgery.


Asunto(s)
Procedimientos Ortopédicos , Cirugía Asistida por Computador , Algoritmos , Pelvis , Cirugía Asistida por Computador/métodos , Computadores , Imagenología Tridimensional/métodos
7.
Adv Mater ; 36(6): e2309753, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37939787

RESUMEN

Zinc powder (Zn-P) anodes have significant advantages in terms of universality and machinability compared with Zn foil anodes. However, their rough surface, which has a high surface area, intensifies the uncontrollable growth of Zn dendrites and parasitic side reactions. In this study, an anti-corrosive Zn-P-based anode with a functional layer formed from a MXene and Cu-THBQ (MXene/Cu-THBQ) heterostructure is successfully fabricated via microfluidic-assisted 3D printing. The unusual anti-corrosive and strong adsorption of Zn ions using the MXene/Cu-THBQ functional layer can effectively homogenize the Zn ion flux and inhibit the hydrogen evolution reaction (HER) during the repeated process of Zn plating/stripping, thus achieving stable Zn cycling. Consequently, a symmetric cell based on Zn-P with the MXene/Cu-THBQ anode exhibits a highly reversible cycling of 1800 h at 2 mA cm-2 /1 mAh cm-2 . Furthermore, a Zn-organic full battery matched with a 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl organic cathode riveted on graphene delivers a high reversible capacity and maintains a long cycle life.

8.
BMC Musculoskelet Disord ; 24(1): 899, 2023 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-37980527

RESUMEN

OBJECTIVE: The purpose of this study was to compare the therapeutic effects of Kirschner wire fixation and external fixation in the treatment of proximal humeral fractures in older children and adolescents. METHODS: A retrospective analysis was performed on the clinical data of older children and adolescents who underwent surgery at our institution for proximal humeral fractures between April 2014 and May 2022. One group (n = 28) underwent fracture reduction and Kirschner wire fixation, and the other group (n = 23) underwent external fixation. During the follow-up, the differences in shoulder joint function between the two groups were compared by analysing Quick Disabilities of the Arm, Shoulder, and Hand (Quick DASH) and Constant-Murley scores. Postoperative complications were also recorded. RESULTS: The operation time of the Kirschner wire group was shorter than that of the external fixation group (69.07 ± 11.34 min vs. 77.39 ± 15.74 min, P = 0.33). The time to remove the fixator in the external fixation group was shorter than that in the Kirschner wire group (6.74 ± 1.57 vs. 7.61 ± 1.22, P = 0.032). The Quick DASH score and Constant-Murley score of the patients in the external fixation group were significantly better than those in the Kirschner wire group at 3 months after surgery (5.63 ± 4.33 vs. 8.93 ± 6.40, P = 0.040; 93.78 ± 2.43 vs. 91.75 ± 2.15, P = 0.003). There was no significant difference in the Quick DASH score or Constant-Murley score between the patients in the external fixator group and those in the Kirschner wire group at 9 months after the operation (2.77 ± 3.14 vs. 3.17 ± 3.68, P = 0.683; 97.39 ± 1.80 vs. 96.57 ± 2.15, P = 0.152). The most common complication of the two groups was pin tract infection. The incidence rate of infection was higher in the external fixation group than that in the Kirschner wire group (9 vs. 4, P = 0.043). CONCLUSION: Both Kirschner wire fixation and external fixation of N-H III and IV proximal humeral fractures in older children and adolescents produce good outcomes. External fixation is a preferred surgical treatment option for paediatric proximal humerus fractures because early mobilization of the affected limb can be realized.


Asunto(s)
Fracturas del Húmero , Fracturas del Hombro , Humanos , Niño , Adolescente , Hilos Ortopédicos , Fijación de Fractura/efectos adversos , Fijadores Externos , Fijación Interna de Fracturas/efectos adversos , Estudios Retrospectivos , Fracturas del Hombro/diagnóstico por imagen , Fracturas del Hombro/cirugía , Resultado del Tratamiento , Fracturas del Húmero/cirugía
9.
Int J Surg ; 109(11): 3395-3406, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37526114

RESUMEN

BACKGROUND: The prognostic nutritional index (PNI) has been proposed as a useful prognostic tool in multiple populations. However, its prognostic value has not been fully evaluated in the hip fracture population. We aimed to assess the relationship between PNI and postoperative complications as well as 2-year all-cause mortality in the hip fracture population. MATERIALS AND METHODS: We included patients aged 45 or older who underwent surgery for hip fracture between 2000 and 2022. The baseline serum albumin and total lymphocyte count were used to calculate PNI with the following formula: 10×serum albumin level (g/dl)+0.005×total lymphocyte count (per mm 3 ). Patients were classified into low, medium, and high categories based on tertiles of PNI (≤43.23, 43.23-47.35, and >47.35, respectively). Logistic regression and Cox proportional hazards models were used to calculate the odds ratio (OR) for postoperative compilations and the hazard ratio (HR) for mortality, adjusting for potential confounders. RESULTS: Of 3351 hip patients, 236 (7.04%) developed postoperative complications, and 305 (9.10%) died during the 2-year follow-up. Compared to the low-category patients, the medium-category and high-category patients showed lower odds of postoperative complications (ORs 0.69, 95% CI 0.48-0.98; and 0.61, 95% CI 0.40-0.93, respectively), and lower hazards of 2-year mortality (HRs 0.66, 95% CI 0.49-0.88; and 0.61, 95% CI 0.42-0.88, respectively). These associations were robust across a series of analyses, including subgroup analyses and dose-response sensitivity analyses. CONCLUSION: PNI is an independent predictor of postoperative complications and 2-year all-cause mortality in hip fracture patients. PNI can be used to identify patients who may be at high risk of a poor prognosis.


Asunto(s)
Fracturas de Cadera , Evaluación Nutricional , Humanos , Estado Nutricional , Pronóstico , Factores de Riesgo , Estudios Retrospectivos , Albúmina Sérica/análisis , Estudios de Cohortes , Fracturas de Cadera/complicaciones , Fracturas de Cadera/cirugía , Complicaciones Posoperatorias
10.
J Colloid Interface Sci ; 650(Pt A): 875-882, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37450976

RESUMEN

Aqueous rechargeable Zn-ion batteries (ARZIBs) are promising for energy storage. However, the Zn dendrite and corrosive reactions on the surface of Zn anode limit the practical uses of ARZIBs. Herein, we present a valid electrolyte additive of NaI, in which I- can modulate the morphology of Zn crystal growth by adsorbing on specific crystal surfaces (002), and guide Zn deposition by inducing a negative charge on the Zn anode. Simultaneously, it enhances the reduction stability of water molecules by participating in the solvation structure of Zn(H2O)62+ by forming ZnI(H2O)5+. At 10 mA cm-2, the assembled Zn symmetrical batteries can run stably over 1,100 h, and the depth of discharge (DOD) can reach 51.3 %. At 1 A g-1, the VO2||Zn full-cell in 2 M ZnCl2 electrolyte with 0.4 M NaI (2 M ZnCl2-0.4 M NaI) maintains of the capacity retention of 75.7 % over 300 cycles. This work offers an insight into inorganic anions as electrolyte additives for achieving stable zinc anodes of ARZIBs.

11.
Nat Commun ; 14(1): 4435, 2023 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-37481665

RESUMEN

The operation of traditional aqueous-electrolyte zinc-ion batteries is adversely affected by the uncontrollable growth of zinc dendrites and the occurrence of side reactions. These problems can be avoided by the development of functional hydrogel electrolytes as replacements for aqueous electrolytes. However, the mechanism by which most hydrogel electrolytes inhibit the growth of zinc dendrites on a zinc anode has not been investigated in detail, and there is a lack of a large-scale recovery method for mainstream hydrogel electrolytes. In this paper, we describe the development of a recyclable and biodegradable hydrogel electrolyte based on natural biomaterials, namely chitosan and polyaspartic acid. The distinctive adsorptivity and inducibility of chitosan and polyaspartic acid in the hydrogel electrolyte triggers a double coupling network and an associated synergistic inhibition mechanism, thereby effectively inhibiting the side reactions on the zinc anode. In addition, this hydrogel electrolyte played a crucial role in an aqueous acid-based Zinc/MnO2 battery, by maintaining its interior two-electron redox reaction and inhibiting the formation of zinc dendrites. Furthermore, the sustainable biomass-based hydrogel electrolyte is biodegradable, and could be recovered from the Zinc/MnO2 battery for subsequent recycling.

12.
Front Bioeng Biotechnol ; 11: 1172934, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37324437

RESUMEN

Objective: In this study, the advantages of the internal fixation configuration composed of uniplanar pedicle screws in the treatment of thoracolumbar fractures were verified by biomechanical experimental methods, which provided the basis for subsequent clinical experiments and clinical applications. Methods: A total of 24 fresh cadaveric spine specimens (T12-L2) were utilized to conduct biomechanical experiments. Two different internal fixation configurations, namely, the 6-screw configuration and the 4-screw/2-NIS (new intermediate screws) configuration, were tested using fixed-axis pedicle screws (FAPS), uniplanar pedicle screws (UPPS), and polyaxial pedicle screws (PAPS) respectively. The spine specimens were uniformly loaded with 8NM pure force couples in the directions of anteflexion, extension, left bending, right bending, left rotation, and right rotation, and the range of motion (ROM) of the T12-L1 and L1-L2 segments of the spine was measured and recorded to access biomechanical stability. Results: No structural damage such as ligament rupture or fracture occurred during all experimental tests. In the 6-screw configuration, the ROM of the specimens in the UPPS group was significantly better than that of the PAPS group but weaker than those of the FAPS group (p < 0.01). In the 4-screw/2-NIS configuration, the results were identical to the biomechanical test results for the 6-screw configuration (p < 0.01). Conclusion: Biomechanical test results show that the internal fixation configuration with UPPS can maintain the stability of the spine well, and the results are better than that of PAPS. UPPS has both the biomechanical advantages of FAPS and the superiority of easy operation of PAPS. We believe it is an optional internal fixation device for minimally invasive treatment of thoracolumbar fractures.

13.
Acta Pharmacol Sin ; 44(9): 1790-1800, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37142683

RESUMEN

Meteorin-like (Metrnl) is a novel secreted protein with various biological activities. In this study, we investigated whether and how Metrnl regulated skin wound healing in mice. Global Metrnl gene knockout mice (Metrnl-/-) and endothelial cell-specific Metrnl gene knockout mice (EC-Metrnl-/-) were generated. Eight-mm-diameter full-thickness excisional wound was made on the dorsum of each mouse. The skin wounds were photographed and analyzed. In C57BL/6 mice, we observed that Metrnl expression levels were markedly increased in skin wound tissues. We found that both global and endothelial cell-specific Metrnl gene knockout significantly retarded mouse skin wound healing, and endothelial Metrnl was the key factor affecting wound healing and angiogenesis. The proliferation, migration and tube formation ability of primary human umbilical vein endothelial cells (HUVECs) were inhibited by Metrnl knockdown, but significantly promoted by addition of recombinant Metrnl (10 ng/mL). Metrnl knockdown abolished the proliferation of endothelial cells stimulated by recombinant VEGFA (10 ng/mL) but not by recombinant bFGF (10 ng/mL). We further revealed that Metrnl deficiency impaired VEGFA downstream AKT/eNOS activation in vitro and in vivo. The damaged angiogenetic activity in Metrnl knockdown HUVECs was partly rescued by addition of AKT activator SC79 (10 µM). In conclusion, Metrnl deficiency retards skin wound healing in mice, which is related to impaired endothelial Metrnl-mediated angiogenesis. Metrnl deficiency impairs angiogenesis by inhibiting AKT/eNOS signaling pathway.


Asunto(s)
Neovascularización Fisiológica , Proteínas Proto-Oncogénicas c-akt , Animales , Humanos , Ratones , Movimiento Celular , Proliferación Celular , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Cicatrización de Heridas
14.
Adv Mater ; 35(36): e2303336, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37200200

RESUMEN

Aqueous Zn ion batteries are promising systems due to their intrinsic safety, low cost, and non-toxicity, and the Zn corrosion and dendrite growth will cause the poor reversibility of Zn anode. Herein, the porous Zn@C solid, hollow, and yolk-shell microsphere films are developed as Zn anode antifluctuator (ZAAF). The prepared yolk-shell microspheres (Zn@C yolk-shell microsphere [ZCYSM]) film with superior buffering can effectively restrict the deposition of Zn metal in its interior and inhibit the volume expansion during plating/stripping process, thus modulating the Zn2+ flux and enabling stable Zn cycling. As a proof of concept, the ZCYSM@Zn symmetric cells achieve the excellent cyclic stability over 4000 h and cumulative plated capacity of 4 Ah cm-2  at a high current density of 10 mA cm-2 . Concomitantly, the suppressed corrosion reactions and dendrite-free ZAAF significantly improve the durability of full cells (coupled to CaV6 O16 ·3H2 O). Additionally, durable pouch cell and electrochemical neuromorphic inorganic device (ENIDe) are integrated to simulate neural network, providing a strategy for extreme interconnectivity comparable to the human brain.

15.
J Youth Adolesc ; 52(6): 1301-1312, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37067641

RESUMEN

Parent-child separation caused by parental migration could have adverse effects on individuals' emotional adaptation. However, research on this topic is limited in its focus on childhood or adolescence samples and solely environmental factors, and less is known about how positive environmental factors, biological factors and parent-child separation experience interact to influence emotional adaptation in emerging adulthood. The present study addressed these issues by investigating the relationships between parent-child cohesion and positive/negative affect, and examining the moderating roles of sympathetic nervous system activity (measured by skin conductance level reactivity, SCLR) and parent-child separation experience in the relationships. Data from 248 college students (Mage = 18.91 years, SD = 0.70; 32.3% males), including 158 college students with parent-child separation experience and 90 college students without parent-child separation experience. The results showed that parent-child cohesion predicted college students' positive/negative affect. Moreover, the moderating role of SCLR on the relationship between father-child cohesion and negative affect varied with parent-child separation experience. Specifically, father-child cohesion negatively predicted negative affect when SCLR was lower for college students with parent-child separation experience, while negatively predicted negative affect when SCLR was higher for college students without parent-child separation experience. These results indicate that the interaction pattern of Biological × Environmental predicting college students' positive/negative affect varies across parent-child separation status in childhood or adolescence.


Asunto(s)
Relaciones Padres-Hijo , Estudiantes , Masculino , Adolescente , Humanos , Adulto , Adulto Joven , Femenino , Estudiantes/psicología , Ajuste Emocional , Sistema Nervioso Simpático , Afecto
16.
Sensors (Basel) ; 23(8)2023 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-37112417

RESUMEN

Aiming at the problem of fast divergence of pure inertial navigation system without correction under the condition of GNSS restricted environment, this paper proposes a multi-mode navigation method with an intelligent virtual sensor based on long short-term memory (LSTM). The training mode, predicting mode, and validation mode for the intelligent virtual sensor are designed. The modes are switching flexibly according to GNSS rejecting situation and the status of the LSTM network of the intelligent virtual sensor. Then the inertial navigation system (INS) is corrected, and the availability of the LSTM network is also maintained. Meanwhile, the fireworks algorithm is adopted to optimize the learning rate and the number of hidden layers of LSTM hyperparameters to improve the estimation performance. The simulation results show that the proposed method can maintain the prediction accuracy of the intelligent virtual sensor online and shorten the training time according to the performance requirements adaptively. Under small sample conditions, the training efficiency and availability ratio of the proposed intelligent virtual sensor are improved significantly more than the neural network (BP) as well as the conventional LSTM network, improving the navigation performance in GNSS restricted environment effectively and efficiently.

18.
Injury ; 54 Suppl 2: S70-S77, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35177266

RESUMEN

PURPOSE: This study was to test the hypothesis that intramedullary (IM) nailing fixation of midshaft clavicle fractures could result in better clinical outcomes and lower complications rates than plating fixation. METHODS: PubMed, Embase, and the Cochrane Library database were used to search all English language published randomized controlled trials (RCTs) of midshaft clavicle fractures using plating versus IM nailing. The characteristics of the study participants were collected. Outcomes of postoperative shoulder functional measurements, operative data and complications rates were meta-analyzed. RESULTS: Eight hundred and ninety-five patients in ten RCTs and three quasi-RCTs were involved in the meta-analysis. The results of meta-analysis of these studies showed that the functional outcome evaluated by the Constant Shoulder and Disabilities of the Arm, Shoulder and Hand (DASH) scores after accepting IM nailing was significantly better than that of plating fixation at one year post-operatively (P < 0.01), with the heterogeneity of 43% and 91%, respectively. Sensitivity analyses of the pooled results of Constant and DASH scores displayed that the functional advantage of IM nailing fixation comes from the subgroup of locked IM nailing. Further, regarding the operative statistics, operative time, blood loss and wound length were significantly less in the IM nailing group than the plating group (P < 0.001). The rates of infection, major complications and complications-related revision surgery were significantly higher in the plating group than the IM nailing group; however, there were no significantly statistical differences in other complications, e.g., nonunion, refracture after hardware removal, implant failure, symptomatic hardware, etc. (P > 0.05). CONCLUSION: The observations in this review suggested that IM nailing, especially locked IM nailing, could provide better shoulder functional outcome at one-year follow-up. Moreover, IM nailing fixation could effectively reduce operative time, blood loss, rates of infection, major complications, and revision surgery than plating. Further high-quality clinical trials with large samples and consistent designs are still needed to verify the long-term functional advantage of locked and unlocked IM nailing for midshaft clavicle fractures. LEVEL OF EVIDENCE: Level II.


Asunto(s)
Fijación Intramedular de Fracturas , Fracturas Óseas , Humanos , Fijación Intramedular de Fracturas/métodos , Clavícula/cirugía , Placas Óseas , Ensayos Clínicos Controlados Aleatorios como Asunto , Fracturas Óseas/terapia
19.
Adv Mater ; 35(9): e2209886, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36515180

RESUMEN

Zn powder (Zn-P)-based anodes are always regarded as ideal anode candidates for zinc ion batteries owing to their low cost and ease of processing. However, the intrinsic negative properties of Zn-P-based anodes such as easy corrosion and uncontrolled dendrite growth have limited their further applications. Herein, a novel 3D cold-trap environment printing (3DCEP) technology is proposed to achieve the MXene and Zn-P (3DCEP-MXene/Zn-P) anode with highly ordered arrangement. Benefitting from the unique inhibition mechanism of high lattice matching and physical confinement effects within the 3DCEP-MXene/Zn-P anode, it can effectively homogenize the Zn2+ flux and alleviate the Zn deposition rate of the 3DCEP-MXene/Zn-P anode during Zn plating-stripping. Consequently, the 3DCEP-MXene/Zn-P anode exhibits a superior cycling lifespan of 1400 h with high coulombic efficiency of ≈9.2% in symmetric batteries. More encouragingly, paired with MXene and Co doped MnHCF cathode via 3D cold-trap environment printing (3 DCEP-MXene/Co-MnHCF), the 3DCEP-MXene/Zn-P//3DCEP-MXene/Co-MnHCF full battery delivers high cyclic durability with the capacity retention of 95.7% after 1600 cycles. This study brings an inspired universal pathway to rapidly fabricate a reversible Zn anode with highly ordered arrangement in a cold environment for micro-zinc storage systems.

20.
J Orthop Res ; 41(5): 1088-1096, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36116025

RESUMEN

To compare the biomechanical stability of slide compression anatomic plates of the femoral neck, cannulated compression screws and dynamic hip screws with derotation screws for stabilizing unstable femoral neck fractures (Pauwels angle = 70°). Pauwels III femoral neck fractures were created on 45 Sawbones femurs and randomly assigned to three implant groups (1:1:1). The biomechanical stability of all Sawbones in each treatment group was evaluated with three tests. First, in the static loading test, the load-displacement curve, vertical stiffness (load/vertical displacement [N/mm]) and 5 mm failure load were recorded. Second, in the incremental cyclic loading test (700, 1000, and 1400 N), the cyclic-displacement curve and the displacement of the fragments were recorded. Third, in the torsion test, the torsional rigidity, maximum torque, and torsional angle corresponding to the maximum torque were recorded. The static compression test showed that slide compression anatomic place-femoral neck (SCAP-FN) had the largest vertical stiffness (275 ± 11 N/mm, p < 0.01) and 5 mm failure load (1232 ± 156, p < 0.01). The cyclic loading test showed that SCAP-FN had the lowest change in displacement after 30000 cycles of loading. The torsional stiffness and the maximum torque followed the order SCAP-FN > dynamic hip screw systems (DHS) + derotational screw (DS) > CCS, and the torsional angle corresponding to the maximum torque followed the order SCAP-FN < DHS + DS < CCS. The SCAP-FN construct provides stiffness and stability compared with other standard fixation techniques (3CS and DHS + DS). The fixation strategy of SCAP-FN might be sufficient for clinical use, indicating studies in the human body are warranted.


Asunto(s)
Fracturas del Cuello Femoral , Cuello Femoral , Humanos , Fenómenos Biomecánicos , Placas Óseas , Tornillos Óseos , Fracturas del Cuello Femoral/cirugía , Cuello Femoral/cirugía , Fijación Interna de Fracturas/métodos
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