Canonical pathways for validating steroid-associated osteonecrosis in mice.

The present study aimed to establish and evaluate a preclinical model of steroid-associated osteonecrosis (SAON) in mice. Sixteen 24-week-old male C57BL/6 mice were used to establish SAON by two intraperitoneal injections of lipopolysaccharide (LPS), followed by three subcutaneous injections of methylprednisolone (MPS). Each injection was conducted on working day, with an interval of 24 h. Six cycles of injections were conducted. Additional twelve mice (age- and gender-matched) were used as normal controls. At 2 and 6 weeks after completing induction, bilateral femora and bilateral tibiae were collected for histological examination, micro-CT scanning, and bulk RNA sequencing. All mice were alive until sacrificed at the indicated time points. The typical SAON lesion was identified by histological evaluation at week 2 and week 6 with increased lacunae and TUNEL+ osteocytes. Micro-CT showed significant bone degeneration at week 6 in SAON model. Histology and histomorphometry showed significantly lower Runx2+ area, mineralizing surface (MS/BS), mineral apposition rate (MAR), bone formation rate (BFR/BS), type H vessels, Ki67+ (proliferating) cells, and higher marrow fat fraction, osteoclast number and TNFα+ areas in SAON group. Bulk RNA-seq revealed changed canonical signaling pathways regulating cell cycle, angiogenesis, osteogenesis, and osteoclastogenesis in the SAON group. The present study successfully established SAON in mice with a combination treatment of LPS and MPS, which could be considered a reliable and reproducible animal model to study the pathophysiology and molecular mechanism of early-stage SAON and to develop potential therapeutic approaches for the prevention and treatment of SAON.

Steep Posterior Tibial Slope and Excessive Anterior Tibial Translation Are Associated With Increased Sagittal Meniscal Extrusion After Posterior Lateral Meniscus Root Repair Combined With Anterior Cruciate Ligament Reconstruction.

Purpose: To (1) evaluate the clinical and radiographic outcomes of patients with primary anterior cruciate ligament reconstruction (ACLR) with type II posterior lateral meniscus root tear (PLMRT) repair and (2) identify whether increased anterior tibial subluxation of the lateral compartment (ATSLC) and steeper posterior tibial slope (PTS) are associated with sagittal lateral meniscal extrusion (LME). Methods: Patients who underwent primary anatomic ACLR with concomitant type II PLMRTs using the all-inside side-to-side repair technique between November 2014 and September 2020 were identified. To be included, patients must have had a minimum of 2 years follow-up. All patients, including those with ATSLC and PTS and sagittal and coronal LME, were retrospectively reviewed clinically and radiologically. The patients were divided into 2 subgroups according to the occurrence of sagittal LME. Results: Forty patients were included in this study with a mean follow-up of 44 months (range, 24-94 months). In general, the postoperative parameters, including grade of pivot shift, side-to-side difference, ATSLC, Lysholm score, and International Knee Documentation Committee (IKDC) score, were significantly improved compared with the preoperative ones. However, postoperative sagittal LME was detected to be significantly larger than the preoperative one. Minimal clinically important difference (MCID) analysis for postoperative outcomes showed that the rate of patients who achieved MCID thresholds was 100% for Lysholm, 95% for IKDC, 42.50% for coronal LME, 62.50% for sagittal LME, 40% for ATSLC, and 100% for side-to-side difference. Further comparisons, where patients were divided into 2 subgroups according to the occurrence of sagittal LME, showed significant differences in PTS, ATSLC, and coronal LME. Conclusions: Clinical outcomes after type II PLMRT repair with primary ACLR were significantly improved, except for LME, at the 2-year postoperative follow-up. After repair of type II PLMRT injuries, the presence of sagittal LME was associated with increased PTS and ATSLC. Level of Evidence: Level III, retrospective cohort study.

Effectiveness of Corticosteroid Therapy in Enhancing Early Postoperative Recovery in Lumbar Spinal Stenosis Patients: A Retrospective Study.

BACKGROUND The degree of postoperative symptom improvement in patients with lumbar spinal stenosis (LSS) is crucial to their postoperative rehabilitation process and functional exercise. Corticosteroids have certain anti-inflammatory effects. This study aimed to explore whether small doses of corticosteroids would improve postoperative neurological symptoms in patients with lumbar spinal stenosis. MATERIAL AND METHODS Patients with lumbar spinal stenosis who underwent open surgery were divided into a corticosteroid therapy group (CTG) and a non-corticosteroid therapy group (NCTG). They were followed up for 24 months after surgery. The numeric rating scale (NRS) for leg pain (NRS-LP) and leg numbness (NRS-LN), Oswestry Disability Index (ODI) scores, and Short Form Health Survey (SF-36) scores of the 2 groups were compared at different time points to evaluate the therapeutic effect. RESULTS Of the 232 eligible patients enrolled, 128 received corticosteroids and 104 did not. At the 1-month postoperative follow-up, patients in the CTG had significantly lower NRS-LP and NRS-LN scores than those in the NCTG (P=0.017; P=0.043). At the 3-month follow-up, the NRS-LP and ODI scores of patients in the CTG were significantly lower than those of the NCTG (P=0.015; P=0.027), and SF-36 scores were significantly higher than that of the NCTG (P=0.012). At the 6-month follow-up, the SF-36 scores of patients in the CTG was significantly higher than that of the NCTG (P=0.008). CONCLUSIONS Small doses of corticosteroid therapy for postoperative lumbar spinal stenosis reduced symptoms and improved quality of life scores after surgery. However, it had little long-term impact on final patient outcomes.

Artificial Intelligence in Scoliosis: Current Applications and Future Directions.

Scoliosis is a three-dimensional deformity of lateral bending and rotation of the spine. Artificial intelligence (AI) is a set of theories and techniques for studying artificial intelligence, which realizes machine intelligence by simulating and expanding human intelligence. With the continuous development of the multidisciplinary integration trend of modern medicine, artificial intelligence is used more and more in the diagnosis and treatment of scoliosis. Artificial intelligence has been widely used in the study of scoliosis and has penetrated into all fields of clinical practice of scoliosis. At present, artificial intelligence has shown good application prospects in early screening, diagnosis, treatment decision making, intraoperative operation, and prognosis prediction of scoliosis. This paper mainly summarizes the application of artificial intelligence in the clinical practice of scoliosis, and briefly introduces the AI model and its specific applications. In addition, this paper also discusses the limitations and future development of artificial intelligence. In the future, artificial intelligence will bring greater convenience to the diagnosis and treatment of scoliosis and provide better therapeutic effects for patients.

Unilateral interlaminar fenestration on the convex side provides a reliable access for intrathecal administration of nusinersen in spinal muscular atrophy: a retrospective study.

BACKGROUND: As the first gene therapy for spinal muscular atrophy (SMA), nusinersen is supposed to be administrated via intrathecal injection regularly for a lifetime. However, for SMA patients with severe spinal deformities, bony fusion following posterior spinal instrumentation sets great obstacles for the application of nusinersen. Therefore, efforts have been devoted to the exploration of appropriate approach for nusinersen administration. This study aims to evaluate the safety and reliability of unilateral interlaminar fenestration on the convex side during spinal fusion surgery for intrathecal nusinersen injection in SMA. RESULTS: SMA patients receiving posterior spinal fusion and interlaminar fenestration in Peking Union Medical College Hospital from January 2020 to October 2021 were retrospectively analyzed. 13 patients were included. Of the 13 patients, 10 were classified into SMA type II and 3 into SMA type III. Distal fusion to pelvis was undertaken in 11 patients; while L5 was selected as the lowest instrumented vertebra in the other 2 patients. All patients received interlaminar fenestration on the convex side only with an area of about 15 mm × 20 mm. Fenestration at L2-L3 level was performed in 6 patients; while L3-L4 level was selected for windowing in the remaining 7 patients. 9 of the 13 patients received lumbar puncture and intrathecal nusinersen administration during the 1-year follow-up, with an accumulative total of 50 times. All injections were performed successfully under ultrasound guidance, with no one transferred to radiographic assistance. No severe complications occurred after injection. CONCLUSIONS: In SMA with severe scoliosis planning to receive posterior spinal fusion, unilateral lumbar interlaminar fenestration on the convex side provides a feasible and reliable access for intrathecal nusinersen administration after surgery.

A two-dimensional hydrodynamics prediction framework for mantle-undulated propulsion robot using multiple proper orthogonal decomposition and long short term memory neural network.

In this paper, a deep learning based framework has been developed to predict hydrodynamic forces on a mantle-undulated propulsion robot (MUPRo). A multiple proper orthogonal decomposition (MPOD) algorithm has been proposed to efficiently identify fluid features near the undulating mantle of the MUPRo globally and locally. The results indicate that theL2error of the solution states near the undulating boundary of the proposed MPOD algorithm converges almost linearly to 0.2%. Furthermore, a hydrodynamics prediction framework has been developed based on the proposed MPOD algorithm, where a long short-term memory neural network predicts the temporal coefficients of the MPOD spatial modes. The developed framework achieves economical and reliable predictions of hydrodynamic forces acting on the undulating boundary compared to simulations and experiments. Moreover, theL2error of the developed framework is one to two orders of magnitude lower than that of the frameworks based on the classical POD algorithm when the degrees of freedom are consistent. Finally, the reliability of the proposed MPOD-NIROM is discussed through an offline parameter planning case of an aquatic-inspired robot. The model presented in this paper can provide support for the offline parameter planning of aquatic-inspired robots.

Silicon Micromachined TSVs for Backside Interconnection of Ultra-Small Pressure Sensors.

This paper presents an ultra-small absolute pressure sensor with a silicon-micromachined TSV backside interconnection for high-performance, high spatial resolution contact pressure sensing, including flexible-substrate applications. By exploiting silicon-micromachined TSVs that are compatibly fabricated with the pressure sensor, the sensing signals are emitted from the chip backside, thereby eliminating the fragile leads on the front-side. Such a design achieves a flat and fully passivated top surface to protect the sensor from mechanical damage, for reliable direct-contact pressure sensing. A single-crystal silicon beam-island structure is designed to reduce the deflection of the pressure-sensing diaphragm and improve output linearity. Using our group-developed microholes interetch and sealing (MIS) micromachining technique, we fabricated ultra-small piezoresistive pressure sensors with the chip size as small as 0.4 mm × 0.6 mm, in which the polysilicon-micromachined TSVs transfer the signal interconnection from the front-side to the backside of the wafer, and the sensor chips can be densely packaged on the flexible substrate via the TSVs. The ultra-small pressure sensor has high sensitivity of 0.84 mV/kPa under 3.3 V of supply voltage and low nonlinearity of ±0.09% full scale (FS) in the measurement range of 120 kPa. The proposed pressure sensors with backside-interconnection TSVs hold promise for tactile sensing applications, including flexible sensing of wearable wristwatches.

Intraband Transition of HgTe Nanocrystals for Long-Wave Infrared Detection at 12 µm.

The synthesis of n-doped HgTe colloidal quantum dots was optimized to produce samples with a 1Se-1Pe intraband transition in the long-wave infrared (8-12 µm). The spin-orbit splitting of 1Pe states places the 1Se-1Pe1/2 transition around 10 µm. The narrow line width of 130 cm-1 at 300 K is limited by the size distribution. This narrowing leads to an absorption coefficient about 5 times stronger than is possible with the HgTe CQD interband transition at similar energies. From 300 to 80 K, the intraband transition blueshifts by 90 cm-1, while the interband transition redshifts by 350 cm-1. These shifts are assigned to the temperature dependence of the band structure. With ∼2 electrons/dot doping at 80 K, a photoconductive film of 80 nm thickness on a quarter wave reflector substrate showed a detectivity (D*) of ∼107 Jones at 500 Hz in the 8-12 µm range.

An integrated nomogram combining deep learning, clinical characteristics and ultrasound features for predicting central lymph node metastasis in papillary thyroid cancer: A multicenter study.

Objective: Central lymph node metastasis (CLNM) is a predictor of poor prognosis for papillary thyroid carcinoma (PTC) patients. The options for surgeon operation or follow-up depend on the state of CLNM while accurate prediction is a challenge for radiologists. The present study aimed to develop and validate an effective preoperative nomogram combining deep learning, clinical characteristics and ultrasound features for predicting CLNM. Materials and methods: In this study, 3359 PTC patients who had undergone total thyroidectomy or thyroid lobectomy from two medical centers were enrolled. The patients were divided into three datasets for training, internal validation and external validation. We constructed an integrated nomogram combining deep learning, clinical characteristics and ultrasound features using multivariable logistic regression to predict CLNM in PTC patients. Results: Multivariate analysis indicated that the AI model-predicted value, multiple, position, microcalcification, abutment/perimeter ratio and US-reported LN status were independent risk factors predicting CLNM. The area under the curve (AUC) for the nomogram to predict CLNM was 0.812 (95% CI, 0.794-0.830) in the training cohort, 0.809 (95% CI, 0.780-0.837) in the internal validation cohort and 0.829(95%CI, 0.785-0.872) in the external validation cohort. Based on the analysis of the decision curve, our integrated nomogram was superior to other models in terms of clinical predictive ability. Conclusion: Our proposed thyroid cancer lymph node metastasis nomogram shows favorable predictive value to assist surgeons in making appropriate surgical decisions in PTC treatment.

1ppm-detectable hydrogen gas sensors by using highly sensitive P+/N+ single-crystalline silicon thermopiles.

Hydrogen (H2) is currently of strategic importance in the pursuit of a decarbonized, environmentally benign, sustainable global energy system; however, the explosive nature of H2 requires leakage monitoring to ensure safe application in industry. Therefore, H2 gas sensors with a high sensitivity and fast response across a wide concentration range are crucial yet technically challenging. In this work, we demonstrate a new type of MEMS differential thermopile gas sensor for the highly sensitive, rapid detection of trace H2 gas in air. Facilitated by a unique MIS fabrication technique, pairs of single-crystalline silicon thermopiles (i.e., sensing and reference thermopiles) are batch fabricated with high-density single-crystalline silicon thermocouples, yielding an outstanding temperature sensitivity at the sub-mK level. Such devices ensure the detection of miniscule temperature changes due to the catalytic reaction of H2 with a detection limit as low as ~1 ppm at an operating temperature of 120 °C. The MEMS differential thermopiles also exhibit a wide linear detection range (1 ppm-2%, more than four orders of magnitude) and fast response and recovery times of 1.9 s and 1.4 s, respectively, when detecting 0.1% H2 in air. Moreover, the sensors show good selectivity against common combustible gases and volatile organics, good repeatability, and long-term stability. The proposed MEMS thermopile H2 sensors hold promise for the trace detection and early warning of H2 leakage in a wide range of applications.

Comparison of Lumbar Fusion Surgical Outcomes Between Patients with Lumbar Spinal Stenosis ≥80 Versus 65-79 Years Old.

BACKGROUND The efficacy of lumbar fusion surgery in patients age 80 years and older with lumbar spinal stenosis (LSS) is still controversial. This retrospective study aimed to evaluate the surgical outcomes of LSS patients ³80 vs 65-79 years. MATERIAL AND METHODS The study included 66 patients diagnosed with LSS from 2014 to 2020; 33 patients were ³80 years and 33 patients were 65-79 years. The 2 groups were matched for sex and surgical segment. All patients underwent posterior lumbar decompression, fixation, and fusion surgery. The Numerical Rating Scale (NRS) of leg and back pain, Oswestry Disability Index (ODI), Short-Form Health Survey (SF-36), and radiographic data were collected before surgery and at 3, 6, and 12 months postoperatively. RESULTS NRS (back) in the ≥80 years group was significantly higher than in the 65-79 years group at 3 months [2 (0-3) vs 1 (0-3), P=0.001]. Improvement of SF-36 (3 months: 15.7±4.9 vs 27.6±5.4, P<0.001; 6 months: 27.3±6.8 vs 31.5±5.6, P=0.011) and Physical Component Score (PCS) (3 months: 6.5±2.5 vs 17.0±3.6, P<0.001; 6 months: 15.9±3.4 vs 20.1±3.1, P<0.001) at 3 and 6 months in the ≥80 years group were significantly smaller than in 65-79 years group. There was a difference of Pfirrmann index of adjacent segment disc between the 2 groups at 12 months [≥80 vs 65-79 years group: 5.5 (4-8) vs 5 (3-8), P=0.003]. CONCLUSIONS Lumbar fusion surgery in patients ≥80 years with LSS can provide comparable improvements in clinical and radiographic outcomes compared with younger patients. Postoperative physiological function recovery was slower in patients ≥80 years.

Ultra-Responsive MEMS Sensing Chip for Differential Thermal Analysis (DTA).

Ultra-responsive single-crystal silicon MEMS thermopiles for differential thermal analysis (DTA) are developed. Facilitated by a unique "microholes interetch and sealing (MIS)" technique, pairs of suspended thermopiles are batch fabricated in a differential form, with high-density (54 pairs) n-type/p-type single-crystal silicon thermocouples integrated within each thermopile (sample area ~0.045 mm2). The fabricated MEMS thermopile sensors exhibit outstanding power responsivity of 99.5 V/W and temperature responsivity of 27.8 mV/°C, which are more than 4 times higher than those reported for material thermal analysis. The high-responsivity MEMS DTA chips allow us to accurately measure the indium melting point at different heating rates of ~1-100 °C/s. We also perform DTA measurement of the dehydration process of CuSO4·5H2O and the crystals show three stages of losing water of crystallization before becoming anhydrous copper sulfate salt. Our high-performance, cost-effective MEMS sensing chips hold promise for rapid and accurate DTA characterization for a wide range of applications.

The regrouping of Luminal B (HER2 negative), a better discriminator of outcome and recurrence score.

BACKGROUND: Breast cancer (BC) remains the leading cause of cancer-related deaths worldwide. High recurrence risk Luminal BC receives adjuvant chemotherapy in addition to standard hormone therapy. Considering the heterogeneity of Luminal B BC, a more accurate classification model is urgently needed. METHODS: In this study, we retrospectively reviewed the data of 1603 patients who were diagnosed with HER2-negative breast invasive ductal carcinoma. According to the expression level of PR and Ki-67 index, the Luminal B (HER2-negative) BCs were divided into three groups: ER+PR-Ki67low (ER-positive, PR-negative, and Ki-67 index <20%), ER+PR+Ki67high (ER-positive, PR-positive, and Ki-67 index ≥20%), and ER+PR-Ki67high (ER-positive, PR-negative, and Ki-67 index ≥20%). The cox proportional hazards regression model was used to evaluate the correlation between each variable and outcomes. Besides, discriminatory accuracy of the models was compared using the area under the receiver operating characteristic curve and log-rank χ2 value. RESULTS: The analysis results showed that there was a significant correlation between subtypes using this newly defined classification and overall survival (p < 0.001) and disease-free survival (DFS) (p < 0.001). Interestingly, patients in the ER+PR-Ki67high subgroup have the worst survival outcome in Luminal B (HER2-negative) subtype, similar to Triple-negative patients. Besides, the ER+PR+Ki67high has worse 5-year DFS compared with Luminal A group. There was a significant relationship between the regrouping subtype and the recurrence score index (RI) (p < 0.001). Moreover, the results showed that patients in ER+PR-Ki67high subtype were more likely to have high RI for distance recurrence (RI-DR) and local recurrence (RI-LRR). Our newly defined classification has a better discrimination ability to predict survival outcome and recurrence score of Luminal B (HER2-negative) BC patients, which may help in clinical decision-making for individual treatment.

Poorer surgical outcomes at 2 years postoperatively in patients with lumbar spinal stenosis with long-term preoperative leg numbness: a single-center retrospective study.

BACKGROUND: The purpose of this study was to assess whether differences in duration of preoperative leg numbness lead to different surgical outcomes. METHODS: This study included patients with lumbar spinal stenosis (LSS) who underwent lumbar fusion surgery in our hospital from January 2018 to September 2020. Patients were divided into three groups based on duration of preoperative leg numbness: no numbness (NN) group, short-term numbness (STN) group (leg numbness ≤ 3 months) and long-term numbness (LTN) group (leg numbness > 3 months). The Numerical Rating Scale of leg pain (NRS-LP) and leg numbness (NRS-LN), Oswestry Disability Index (ODI) and Short-Form Health Survey (SF-36) were collected before surgery and at 3, 6, 12 and 24 months postoperatively. RESULTS: 178 patients were included in this study. At 24 months postoperatively, NRS-LP was significantly higher in LTN than in NN [NN vs. STN vs. LTN: 0 (0,1) vs. 0 (0,1) vs. 1 (0,1)] (p = 0.033). NRS-LN in STN [2 (1,3)] was significantly lower than in LTN [3 (2,3)] (p < 0.001). SF-36 was significantly lower in LTN than in other two groups (NN vs. STN vs. LTN: 86.10 ± 6.02 vs. 84.09 ± 5.59 vs. 78.93 ± 6.57) (p < 0.001). ODI was significantly higher in LTN than in other two groups [NN vs. STN vs. LTN: 18 (15,22) vs. 18 (16,20) vs. 21 (19,24)] (p = 0.001). CONCLUSIONS: Patients with LSS with long-term preoperative leg numbness have poorer outcomes at 2 years postoperatively. Surgical intervention should be performed before persistent leg numbness for more than 3 months to obtain a better prognosis.

Propulsion optimization of a jellyfish-inspired robot based on a nonintrusive reduced-order model with proper orthogonal decomposition.

In this research, the propulsion of the proposed jellyfish-inspired mantle undulated propulsion robot (MUPRo) is optimized. To reliably predict the hydrodynamic forces acting on the robot, the proposed nonintrusive reduced-order model (NIROM) based on proper orthogonal decomposition (POD) additionally considers the POD basis that makes an important contribution to the features on the specified boundary. The proposed model establishes a mapping between the parameter-driven motion of the mantle and the evolution of the fluid characteristics around the swimmer. Moreover, to predict new cases where the input needs to be updated, the input of the proposed model is taken from the kinematics of the robot rather than extracted from full-order high-fidelity models. In this paper, it takes approximately 950 s to perform a simulation using the full-order high-fidelity model. However, the computational cost for one prediction with the proposed POD-NIROM is around 0.54 s, of which about 0.2 s is contributed by preprocessing. Compared with the NIROM based on the classic POD method, the proposed POD-NIROM can effectively update the input and reasonably predict the characteristics on the boundary. The analysis of the hydrodynamic performance of the MUPRo pinpoints that, over a certain period and with a certain undulation amplitude, the hydrodynamic force generated by the swinging-like mantle motion (k< 0.5) is greater, outperformingAequorea victoriain startup acceleration. It is demonstrated that considering a certain power loss and a certain tail beat amplitude, the wave-like mantle motion (k> 0.5) can produce greater propulsion, which means higher propulsion efficiency.

The role of 18F-FDG PET/CT metabolic parameters in pediatric lymphoblastic lymphoma.

OBJECTIVE: This retrospective study aimed to evaluate the role of metabolic parameters of 18F-FDG PET/CT in pediatric lymphoblastic lymphoma (LBL). METHODS: Thirty patients with LBL underwent 42 scans. Metabolic parameters including maximum standardized uptake value (SUVmax), total metabolic tumor volume (TMTV), and total lesion glycolysis (TLG) were measured at baseline PET/CT. Univariate and multivariate analysis for survival were performed to assess their prognostic value. Twelve patients underwent PET/CT after reinduction regime, and the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of PET/CT for predicting relapse were calculated. RESULTS: Patients with stage Ⅳ had a higher TMTV than those with stage III (p = 0.031). Besides, patients with T-LBL or mediastinal involvement had a high TMTV and TLG (p < 0.05). There was no significant difference in PET/CT metabolic parameters between patients with different outcomes (p > 0.05). Children with a low TMTV (<242.91 cm³) had a better 3-year EFS compared with those with a high TMTV (88.9% vs. 56.3%; p = 0.036). SUVmax and TLG were not predictive of EFS (p = 0.874; p = 0.152). However, none of the metabolic parameters of baseline PET/CT were independent prognostic factors for outcomes of pediatric LBL. PET/CT underwent after reinduction regime present with higher sensitivity (50% vs. 0%) and NPV (90% vs. 83.3%) for predicting relapse than CT alone. CONCLUSIONS: Metabolic parameters of baseline PET/CT were not predictive of outcomes in children with LBL. PET/CT done after the reinduction regime had better sensitivity and NPV than CT alone, and a negative scan could be a reliable indicator for sustained remission.

Chip-Based MEMS Platform for Thermogravimetric/Differential Thermal Analysis (TG/DTA) Joint Characterization of Materials.

Combined use of thermal analysis techniques can realize complementarity of different characterization methods. Comprehensive thermal analysis with both thermogravimetric analysis and differential thermal analysis (TG/DTA) can measure not only mass change of a sample but also its temperature change during programmed heating-induced reaction or phase transition processes, thereby obtaining multiaspect thermal information of the material such as dehydration, structural decomposition, phase change and thermal stability. This study proposes and develops a MEMS chip-based TG/DTA microsystem that integrates both programmed heating and detecting elements into a TG chip and a DTA chip to enable the microinstrument performing TG/DTA joint characterization under microscope observation. The TG chip contains a self-heating resonant microcantilever to measure heating-induced mass change of a sample and the DTA chip is with a microheater and a temperature-detecting thermopile integrated on a suspended thermal-insulating diaphragm. Only nanogram and microgram-level samples are needed for the TG and DTA chips, thereby achieving safe measurement to energetic materials such as strong oxidants. The chip-based microinstrument surpasses the state-of-the-art commercial TG/DTA instruments that have, in the long term, suffered from large sample-amount (milligram level) requirements and have been unable to measure energetic materials. Compared with commercial instruments, the chip-based microinstrument is advantageous given its more accurate analysis, much higher heating rate, much smaller instrument volume and much lower power consumption, etc. The microinstrument has been fabricated by using wafer-level MEMS techniques. Testing results show that the mass-detection sensitivity of the TG-chip is as high as 0.45 Hz/pg in air and the temperature sensitivity of the DTA chip achieves 2.9 mV/K under the high heating rate of 25 °C/s. The strong oxidant of KMnO4 is analyzed with the TG/DTA joint characterization under microscopic observation. At the same time as microscope observation of the thermal decomposition phenomena, two-step thermal decomposition process of KMnO4 is identified and the thermal decomposition temperatures are obtained. The TG/DTA microinstrument is promising to be applied for study of various materials.

The lanthanide doping effect on toluene catalytic oxidation over Pt/CeO2 catalyst.

The present work was undertaken to know the lanthanide doping effect on the physicochemical properties of Pt/CeO2 catalysts and their catalytic activity for toluene oxidation. A series of lanthanide ions (La, Pr, Nd, Sm and Gd) were incorporated into ceria lattice by hydrothermal method, and the Pt nanoparticles with equal quality were successfully loaded on various ceria-based supports. Their catalytic performance toward toluene oxidation shows a remarkable lanthanide-doping effect, and the activity is much dependent on the ion radius and valence state of dopants. Owing to smaller ion radius and low valence state, the dopant of Gd would form more Gd-Ce complex and less GdO8-type complex, generating more oxygen vacancies and then promoting oxygen replenishment. Furthermore, the high concentration of oxygen vacancy would drive electrons to transfer from support to metal, and thus electron-rich and under-coordinated Pt particles that are favorable for toluene adsorption and dissociation are obtained. Attributing to above positive factors, the doping of Gd would effectively enhance the catalytic oxidation of toluene over Pt/CeO2 catalyst. In addition, the Pt/CeGdO2 sample exhibits an excellent reaction stability and resistance of concentration impact.

Effect of personality traits on rehabilitation effect after anterior cruciate ligament reconstruction: An observational study.

BACKGROUND: Anterior cruciate ligament (ACL) reconstruction requires an extended period of postoperative rehabilitation. Psychological factors can affect recovery after surgery. Study of psychological factors is still limited to self-motivation, fear and pain. Study of personality traits associated with early rehabilitation outcome after ACL reconstruction is scarce. OBJECTIVE: We aimed to explore the effect of personality traits on early rehabilitation after ACL reconstruction and provide a reference for clinicians in designing a personalized rehabilitation plan. METHODS: This prospective analysis investigated 155 patients at 3 and 6 months after ACL reconstruction. Follow-up involved administration of a general data questionnaire, the Chinese Big Five Personality Inventory Brief Version, the Tegner activity score, the International Knee Documentation Committee Subjective Knee Score, the Knee injury and Osteoarthritis Outcome Score, the Lysholm Score and a balance test. RESULTS: Among the 155 patients included (124 males), Neuroticism was negatively correlated with subjective knee scores at 3 and 6 months after surgery (p<0.001). The odds of a poor balance test result was increased for each 1-point increase in Neuroticism score (odds ratio [OR] 1.74, 95% confidence interval [CI] 1.28-2.36, p<0.001). We found a positive correlation between Conscientiousness score and subjective knee scores at 3 and 6 months after surgery (p<0.001). For every 1-point increase in Conscientiousness score, the odds of a poor balance test result were decreased (OR 0.29, 95% CI 0.16-0.54, p<0.001). Agreeableness and Openness to experience scores were positively correlated with subjective knee scores at 3 and 6 months after surgery (p<0.001). We found no correlation between Extraversion and subjective knee scores at 3 and 6 months after surgery (p>0.05) but a positive correlation with the Tegner activity score at 3 and 6 months after surgery (p<0.05). CONCLUSION: We found a significant correlation between the Big Five personality dimensions and the early rehabilitation effect after ACL reconstruction, which can provide a reference for clinicians in designing a personalized rehabilitation plan.

Comparison of Function- and Activity-Related Outcomes After Anterior Talofibular Ligament Repair With 1 Versus 2 Suture Anchors.

BACKGROUND: Few studies have compared the clinical outcomes of using 1 versus 2 suture anchors for anterior talofibular ligament (ATFL) repair. PURPOSE: To compare the function and activity-related outcomes of arthroscopic ATFL repair using 1 versus 2 suture anchors. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: This retrospective study involved 46 patients (22 patients in the 1-anchor group, 24 patients in the 2-anchor group) who underwent ATFL repair between January 2015 and December 2017. American Orthopaedic Foot & Ankle Society score, Karlsson and Peterson score, and Tegner activity level were evaluated preoperatively and ≥2.5 years postoperatively. At follow-up, patients were also asked about time to return to sport as well as level and intensity of physical fitness. Satisfaction was evaluated with the Sefton grading system. RESULTS: After ≥2.5 years of follow-up (30 months in the 1-anchor group, 33 months in the 2-anchor group), patients in the 2-anchor group had a higher Tegner activity level than those in the 1-anchor group (mean ± SD, 4.75 ± 1.07 vs 4.05 ± 1.17; P = .039). As compared with patients in the 2-anchor group, fewer patients in the 1-anchor group returned to their preoperative activity level (54.2% vs 22.9%; P = .029); the rate of activity at the same or higher intensity as preinjury was also lower in the 1-anchor group (50% vs 79.2%; P = .038). However, there were no differences between the groups in terms of American Orthopaedic Foot & Ankle Society and Karlsson and Peterson scores, time to return to work/sport, duration of activity participation, level of physical fitness, or satisfaction according to Sefton grading. CONCLUSION: Arthroscopic ATFL repair appears to be an effective treatment regardless of whether 1 or 2 suture anchors are used. The techniques had similar functional outcome scores, but 1-anchor repair produced inferior activity-related outcomes.