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Interbody fusion devices are critical in spinal surgery to restore spinal stability, reduce pain and improve function. Polyetheretherketone (PEEK) has become a commonly used alternative material for fusion cages owing to its excellent mechanical properties and biocompatibility, but its biological inertness limits bone regeneration and may lead to poor fusion. In this study, a novel strategy for preparing bioactive biomineralized PEEK cages was developed using a unique combination of osteoinductive CaP bioceramic fillings in the cage window, acid sulfonation and simulated body fluid incubation. In vitro experiments showed that biomineralized PEEK cages and CaP bioceramics regulate immunity and promote angiogenesis and bone integration via activation of hypoxia-inducible factor 1-alpha and cyclic guanosine monophosphate/protein kinase G signaling pathways. In vivo goat spinal fusion experiments demonstrated that PEEK cages filled with CaP bioceramics resulted in good bone growth and spinal fusion. Therefore, the high mechanical strength and good biocompatibility of biomineralized PEEK cages, together with the excellent bioactivity and degradation properties of CaP bioceramics, provide an ideal microenvironment for bone fusion. The development of this composite material not only addresses some of the limitations of existing fusion devices but also will facilitate the development of spinal fusion technology.

Dryness is a critical limiting factor for achieving high agricultural productivity on China’s Loess Plateau (LP). High-precision, field-scale dryness monitoring is essential for the implementation of precision agriculture. However, obtaining dryness information with adequate spatial and temporal resolution remains a significant challenge. Unmanned aerial vehicle (UAV) systems can capture high-resolution remote sensing images on demand, but the effectiveness of UAV-based dryness indices in mapping the high-resolution spatial heterogeneity of dryness across different crop areas at the agricultural field scale on the LP has yet to be fully explored. Here, we conducted UAV–ground synchronized experiments on three typical croplands in the eastern Gansu province of the Loess Plateau (LP). Multispectral and thermal infrared sensors mounted on the UAV were used to collect high-resolution multispectral and thermal images. The temperature vegetation dryness index (TVDI) and the temperature–vegetation–soil moisture dryness index (TVMDI) were calculated based on UAV imagery. A total of 14 vegetation indices (VIs) were employed to construct various VI-based TVDIs, and the optimal VI was selected. Correlation analysis and Gradient Structure Similarity (GSSIM) were applied to evaluate the suitability and spatial differences between the TVDI and TVMDI for dryness monitoring. The results indicate that TVDIs constructed using the normalized difference vegetation index (NDVI) and the visible atmospherically resistant index (VARI) were more consistent with the characteristics of crop responses to dryness stress. Furthermore, the TVDI demonstrated higher sensitivity in dryness monitoring compared with the TVMDI, making it more suitable for assessing dryness variations in rain-fed agriculture in arid regions.

This study investigates the spatial patterns of residential migration among older adults in the city center of Yancheng and the influencing factors using data on the home purchases of individuals aged 65 and older from 2016 to 2018, along with peripheral point of interest (POI) data, analyzed with ArcGIS and a decision tree model. The results indicated that persons aged 60–65 accounted for 42.8% of the total sample and primarily chose to migrate in the early stages of retirement. The intra-city migration of older adults exhibits both centripetal and centrifugal patterns, with a greater tendency toward the city center. House prices, floor levels, and commercial facilities significantly impact their choice of migration destinations. Among these, house prices were the most critical determinant, with the majority of older adults migrating to neighborhoods with lower house prices. This study contributes by integrating residential migration and location choice research and constructing an analytical framework based on facility accessibility. The findings provide insights into the key determinants of location choice for intra-city residential migration among older adults and the construction of livable neighborhoods for them.

This paper aims to characterize the varied urban settings community-based elderly care facilities are located, and examine whether characteristics of urban built environments influence the number of older people attending care facilities for multiple services. The dataset incorporates 108 cases of community-based elderly care facilities and usage records from over 17000 users collected in the Chinese city of Nanjing. A network-based approach was employed to comprehensively describe urban built environments surrounding care facilities with a series of metrics on street morphology and land-uses. It was found that urban built environments significantly influenced the number of users attending care facilities. Facilities having more users tended to locate in places with more shops and stores, on major arterial streets of the city, or inside large housing estates in the outer city. Moreover, urban factors performed differently in affecting users of different services as services accepting spontaneous users were more likely to be influenced by street morphology. This study revealed specific urban factors facilitating older people's usage of care resources. It also generated practical implications regarding the strategies for the planning of spatial locations and service provision to improve the utilization of community-based elderly care.

[Introduction] With the rapid development of AC/DC distribution networks and distributed generation technology, the role of DC microgrids in distribution networks is becoming increasingly important and will become an important component of future distribution networks. Due to the small coverage area and low line impedance of the DC microgrid, when an inter pole short circuit fault occurs, the fault current increases rapidly and has a large amplitude, which can reach more than 10 times the rated working current. This makes it difficult to set the protection of DC microgrids and requires high equipment selection, which restricts the rapid development of DC microgrids. [Method] In response to the above issues, taking the DC microgrid as the research object, starting from the working principle of inter pole faults in the DC microgrid, the fault characteristics on the DC side of the DC microgrid were analyzed. In response to the shortcomings of existing main current limiting methods, a voltage controllable fault current controller was proposed to achieve precise control of fault current. The simulation model of DC microgrid and fault current controller was built for simulation verification. [Result] The simulation results show that the fault current controller can significantly reduce the fault current and achieve precise control of the fault current, making the system controllable before and after the fault without locking the protection. During steady-state operation, the fault current controller can also assist the VSC (Voltage Source Converter) in further stabilizing the DC bus voltage. [Conclusion] To cooperate with the normal operation of the relay protection device and avoid VSC triggering overcurrent protection blocking, it is recommended to set the fault current control range between 1~2 pu.

The development of osteoimmunology has highlighted the crucial role of biomaterial surface topography in modulating macrophage responses, subsequently affecting bone formation. However, the underlying mechanism remains largely unexplored. This study introduced two biphasic calcium phosphate (BCP) ceramics with different surface architecture, finding that compared to micron-scale counterparts (BCP2, ∼3.07 μm), BCP with submicron-scale structure (BCP1, ∼0.66 μm) enhanced ectopic bone formation and facilitated M2 macrophage polarization in vivo. Previous studies have focused predominantly on soluble cytokines secreted by macrophages, the significance of exosomes in intercellular communication has been overlooked. This study isolated exosomes from macrophages treated with either submicron- or micron-scale surfaces, designated as B1-Exos and B2-Exos, respectively. Notably, B1-Exos could significantly improve osteogenic differentiation of mesenchymal stem cells (MSCs), potentially attributable to miRNA cargos within these exosomes. SmallRNA sequencing, western blotting, qRT-PCR, and bioinformatics analyses indicated that submicron-sized BCP1 ceramic markedly elevated miR-142a-5p levels in macrophage-derived exosomes, activating the PTEN/AKT signaling pathway, and consequently guiding the differentiation of MSCs towards osteoblast lineage. These findings not only deepen our understanding of the biomaterial-mediated osteoinduction mechanism, but also inform the design of bone repair materials with specialized surface design for proper immunomodulation to initiate osteogenesis.

The crux of building and planning standards for age-friendly built environment in all countries resides in the regulation of age-friendly built environment practices, yet there exist variations in the representation of content dimensions. The UK is distinguished by its discretionary approach to guidance, whereas China exhibits a highly controlled disposition. Control and guidance may appear to be antithetical, it is essential to recognize that the building and planning standards for age-friendly built environment in both countries never deviate from the legal constraints while providing guidance in achieving age-friendly environments, thus striking a delicate balance between control and guidance. The study examines the standard systems of national standards, local standards and organizational standards, as well as the three dimensions of foundation standards, generic standards and specialized standards. The analysis of building and planning standards for age-friendly built environment in the UK and China scrutinizes the disparities between control and guidance, identifying similarities and differences in the building and planning standard system and content dimensions of the two countries. This analysis serves as a valuable reference for the development of building and planning standards for age-friendly built environment in China.

Acquiring high-performance calcium phosphate (CaP) ceramics via 3D printing is critical for their applications in bone regenerative repair. In current study, a complete process study of 3D printed CaP ceramics based on digital light processing (DLP) technology was performed to get the ideal implant for the regenerative repair of calvarial defects. The smaller particle size of initial powder would be more favorable to getting slurry with high solid content and low viscosity. CaP green body with high precision and high curing rate could be fabricated at the exposure energy density and exposure time of 6.20 mJ cm−2 and 2 s, respectively. Moreover, the post-curing treatment could eliminate the interlayer cracks and increase the curing rate from 69.78% to 93.91% of green body. After that, the mechanical strength of CaP ceramics increased by 46.34%. In-vitro cellular experiments showed that 3D printed CaP ceramics had good biocompatibility, and could promote the osteoblastic differentiation of BMSCs. In-vivo rat cranial defect implantation revealed 3D printed CaP ceramics exhibited better osteogenic ability than the commercial ones (BAM®), reaching the close level with the autografts. Overall, this study could provide a closed-loop solution for 3D printed CaP ceramics with high-precision and low-defect to induce bone regeneration.

Osteoinductivity is a crucial factor to determine the success and efficiency of posterolateral spinal fusion (PLF) by employing calcium phosphate (Ca-P) bioceramics. In this study, three kinds of Ca-P ceramics with microscale to nanoscale gain size (BCP-control, BCP-micro and BCP-nano) were prepared and their physicochemical properties were characterized. BCP-nano had the spherical shape and nanoscale gain size, BCP-micro had the spherical shape and microscale gain size, and BCP-control (BAM®) had the irregular shape and microscale gain size. The obtained BCP-nano with specific nanotopography could well regulate in vitro protein adsorption and osteogenic differentiation of MC3T3 cells. In vivo rabbit PLF procedures further confirmed that nanotopography of BCP-nano might be responsible for the stronger bone regenerative ability comparing with BCP-micro and BCP-control. Collectedly, due to nanocrystal similarity with natural bone apatite, BCP-nano has excellent efficacy in guiding bone regeneration of PLF, and holds great potentials to become an alternative to standard bone grafts for future clinical applications.

So far, how to achieve the optimal regenerative repair of large load-bearing bone defects using artificial bone grafts is a huge challenge in clinic. In this study, a strategy of combining osteoinductive biphasic calcium phosphate (BCP) bioceramic scaffolds with intramedullary nail fixation for creating stable osteogenic microenvironment was applied to repair large segmental bone defects (3.0 cm in length) in goat femur model. The material characterization results showed that the BCP scaffold had the initial compressive strength of over 2.0 MPa, and total porosity of 84%. The cell culture experiments demonstrated that the scaffold had the excellent ability to promote the proliferation and osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (BMSCs). The in vivo results showed that the intramedullary nail fixation maintained the initial stability and structural integrity of the implants at early stage, promoting the osteogenic process both guided and induced by the BCP scaffolds. At 9 months postoperatively, good integration between the implants and host bone was observed, and a large amount of newborn bones formed, accompanying with the degradation of the material. At 18 months postoperatively, almost the complete new bone substitution in the defect area was achieved. The maximum bending strength of the repaired bone defects reached to the 100% of normal femur at 18 months post-surgery. Our results demonstrated the good potential of osteoinductive BCP bioceramics in the regenerative repair of large load-bearing bone defects. The current study could provide an effective method to treat the clinical large segmental bone defects.

High efficiency monochrome red and white OLEDs were realized through the control of dopant concentration by employing the exciplex mCP:PO-T2T as host. The red OLED based on exciplex host achieved the maximum external quantum efficiency (EQE) of 21%, a 44% increase compared with traditional CBP single host. Further, the white OLED with maximum current efficiency, power efficiency and EQE of 41.2 cd/A, 43.1 lm/W, and 19.5%, respectively, was obtained by decreasing the dopant concentration to achieve the simultaneous emission of exciplex host and dopant emitter. The results demonstrate that the barrier-free charge injection, balanced charge transport/recombination, and high triplet excition harvest are responsible for the high efficiency.

The sliding mode observer (SMO)–based sensorless control is essentially a discontinuous switching control algorithm. Therefore, there is large speed or torque chattering in the permanent magnet synchronous motor (PMSM) with existing sliding mode observer–based control methods. In order to solve this problem well, an algorithm based on an improved sliding mode observer is proposed. In detail, the piecewise power function approach is used to replace the traditional ones, that is, the sgn function or the sigmoid function approach. Simulation verifications are conducted to validate the effectiveness of the proposed observer. It shows that the piecewise power function–based sliding mode observer algorithm has obvious advantages in the stability of the three-phase current, namely, it improves the estimation accuracy of the rotor position, rotor speed, and dynamic response to various loads. For further verification, the proposed sliding mode observer algorithm is implemented and verified in a marine electric propulsion motor with a DSP chip of TMS320F28377D. Experimental results validate that the piecewise power function–based sliding mode observer algorithm has high control accuracy and fewer fluctuations, which are all vital in marine engineering.

Abstract Objective To evaluate the effects of yoga on exercise capacity and quality of life in patients with lymphangioleiomyomatosis (LAM), a rare cystic lung disease in women. Patients and methods This was a nonrandomized, controlled study conducted in Beijing, China (August 27, 2017 – April 26, 2018). Twenty-six participants were allocated to the intervention (yoga) group (n = 13) or control group (n = 13). The yoga intervention involved a 24-week program of yoga class training for 90 min once a week and no fewer than 2 at-home sessions per week (at least 15 min per session). The 6-min walking distance (6MWD), lung function, serum vascular endothelial growth factor-D (VEGF-D) levels, quality of life, and symptoms of anxiety and depression were measured at baseline, 12-week and 24-week follow-up. An incremental cardiopulmonary exercise test was conducted at baseline and the 24-week follow-up. Results Eleven patients completed the yoga training program. The yoga group exhibited improvements in the following outcomes versus those of the control group: 6MWD (+ 55 ± 29 m vs + 18 ± 49 m, P = 0.04), anaerobic threshold (3.4 ± 2.4 ml/min/kg vs 1.6 ± 1.4 ml/min/kg, P = 0.035) and peak work load (11.7 ± 14.6 W vs 0.2 ± 9.1 W, P = 0.027). There was no significant difference in peak oxygen consumption (VO2peak), lung function, VEGF-D level, and quality of life between the yoga and control groups. No adverse effects were found in the yoga group. Conclusion Yoga is a feasible and safe intervention for pulmonary rehabilitation and potentially improves exercise capacity in patients with LAM. Trial registration (Clinical trial registration number at www.chictr.org.cn : ChiCTR-OON-1701274)

Early neovascularization and osteoinductivity are two key factors to determine the regenerative abilities of biphasic calcium phosphate (BCP) bioceramics in bone repair. Due to the uncontrolled pore structure and large grain size, the biological performances of the conventional BCP bioceramics is restricted to a large extent. Herein, this study attempted to fabricate BCP bioceramics with appropriately uniform macropores and abundant micropores by combining the advantages of the H2O2 foaming method with the microsphere-sintering method, and different sintering methods were adopted to adjust the micro-nano topography. Due to the optimal design of macropore distribution and nano topography, the obtained BCP bioceramics could well trigger and regulate in vitro biological responses, such as degradation, bone-like apatite formation, protein adsorption, cell spreading, angiogenic and osteogenic differentiation. In vivo canine intramuscular implantation further revealed that the nano topography and appropriately uniform macropores might be responsible for the early neovascularization and osteoinductivity of the prepared BCP bioceramics. Collectedly, the neovascularization and osteoinductivity of BCP bioceramics were further enhanced by optimally designing the pore structure and micro-nano topography, which hold huge potential to be an alternative to the gold standard of autogenous bone in bone repairing applications.

Recent studies on osteoimmunology have revealed the indispensable role of immune cells in osteogenesis. The surface topography of biomaterials plays a critical role in regulating cellular behaviors; however, little attention is paid to its effects on the immune response. Three dense hydroxyapatite (HA) disks with grain size in nano-scale (∼100 nm) to submicron (∼500 nm) range were prepared to investigate their role in macrophage polarization and functional status. It was found that HA ceramics with nano-topography promoted macrophage phenotypic switching from the pro-inflammatory M1 type to the pro-healing M2 type. A reduction in grain size could significantly inhibit the secretion of pro-inflammatory cytokine and increase the proportion of CD206+ M2 population in vitro. Meanwhile, nano-topography could reduce tissue inflammation, up-regulate gene expression of M2 phenotypic marker, and raise the fraction of ARG+ M2 macrophages in vivo. This might be attributed to the differential integrin expression to regulate the activation of intracellular signaling cascades. These findings indicate that the surface topography of HA ceramics regulates macrophage responses, thereby adjusting inflammation and subsequent tissue regeneration. An improved understanding of the relationship between material features and its immunomodulatory potential may help to design bone substitute materials with good biological performance.

The regeneration of bone defects in osteoporotic patients presents a big challenge. Icariin (Ica), which is the main active component of traditional Chinese medicine - herba epimedii, has been widely loaded to scaffolds for the treatment of bone fracture and osteoporosis. To increase drug loading capacity, and meanwhile achieve a stable and safe drug delivery, in present study, a novel icariin derivative - thiolated icariin (Ica-SH) molecule with good cytocompatibility and bioactivity was incorporated into biphasic calcium phosphate (BCP) ceramic scaffold through Ica-SH intermolecular disulfide bonds (abbr., Ica-SH/BCP) to form film coating. Compared with Ica-loaded BCP scaffolds via physical adsorption (abbr., Ica/BCP), the formation of Ica-SH intermolecular disulfide bonds in Ica-SH/BCP scaffolds led to a decreased real-time drug release concentration, and a reduced drug release rate. The released drug from Ica-SH/BCP scaffolds could promote the proliferation, migration, and osteoblastic differentiation of ovariectomized rat bone mesenchymal stem cells (OVX-rBMSCs), and up-regulate the angiogenic gene expression in human umbilical vein endothelial cells (HUVECs) in vitro. The OVX-rat femoral condyle defect model also demonstrated that Ica-SH/BCP scaffolds promoted a superior bone regeneration in osteoporotic animals than BCP ones. These findings suggest that Ica-SH is a promising drug, which can be facilely incorporated into a variety of scaffolds for repairing bone defects of patients, in particular the ones with osteoporosis.

Nine-switch inverters were designed by sharing three-switches to realize dual-outputs, which are normally realized by two three phase inverters with 12 power semiconductors. Therefore, its modulation strategy is very complex and hard to implement. For this reason, a simplified modulations strategy for the nine-switch inverter is proposed. Based on the switched system model, m-modes controllability of the nine-switch inverter is first proposed to design a simplified space vector pulse width modulation (SVPWM) strategy. Compared with the conventional SVPWM strategies, the newly proposed switching scheme cannot only reduce half of the operating modes but also reduce the switching frequencies. It is significant since it can simplify the control, increase power efficiency and reduce economy cost. Finally, a prototype is designed to verify the proposed modulation strategy.

Nausea and vomiting are among the most common and distressing side effects of chemotherapy. Additional antiemetic drugs are urgently needed to effectively manage and ameliorate chemotherapy-induced nausea and vomiting (CINV). The efficacy of ginger as an antiemetic modality for ameliorating CINV has not been established in previous studies. The aim of this study was to examine the efficacy of ginger, as an adjuvant drug to standard antiemetic therapy, in ameliorating acute and delayed CINV in patients with lung cancer receiving cisplatin-based regimens. In this randomized, double-blind, placebo-controlled clinical trial, 140 patients with lung cancer receiving cisplatin-based regimens were enrolled and allocated to receive either ginger root powder or a placebo. Ginger root powder was administered orally (0.5 g, 2 capsules per day, 0.25 g per capsule, every 12 hours) for 5 days beginning on the first day of chemotherapy. The incidence and severity of acute and delayed nausea and vomiting were assessed using the MASCC (Multinational Association for Supportive Care in Cancer) Antiemesis Tool (MAT). Adverse effects and patient adherence were also assessed in this study. No significant difference was observed between the ginger and control groups in the reduction of the incidence and severity of nausea and vomiting ( P > .05). No significant difference in adverse events was observed between the 2 groups ( P > .05). No study-treatment-related adverse events were observed in this study. As an adjuvant drug to standard antiemetic therapy, ginger had no additional efficacy in ameliorating CINV in patients with lung cancer receiving cisplatin-based regimens.