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OBJECTIVE: This study aimed to investigate the effects of epidural analgesia administered as early as cervical dilatation of 1 cm on labor interventions and maternal and neonatal outcomes. METHODS: This retrospective research recruited 1007 full-term primigravidas, who were distributed to two separate cohorts for eligibility: epidural analgesia 1 (cervical dilatation = 1 cm) and epidural analgesia 2 (cervical dilatation >1 cm). Labor interventions (artificial rupture of membranes and oxytocin administration) and duration of labor were the primary outcomes. RESULTS: The effect of initiation timing of epidural analgesia on artificial membrane rupture was not statistically significant (adjusted odds ratio [OR]: 0.85 [0.58-1.24], p > 0.05). Less oxytocin was used in the epidural analgesia 2 group compared with the epidural analgesia 1 group (the adjusted OR: 0.68 [0.49-0.95], p < 0.05). There were no significant differences in the median time to latent phase of labor, active phase of labor, second, and third stages of labor (p > 0.05). There were no significant differences in maternal and neonatal outcomes between the epidural analgesia 1 group and the epidural analgesia 2 group. CONCLUSION: Epidural analgesia could be administered at cervical dilatation = 1 cm.

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Implant-related infections caused by drug-resistant bacteria remain a major challenge faced by orthopedic surgeons. Furthermore, ideal prevention and treatment methods are lacking in clinical practice. Here, based on the antibacterial and osteogenic properties of Zn alloys, Ag and Li were selected as alloying elements to prepare biodegradable Zn-Li-Ag ternary alloys. Li and Ag addition improved the mechanical properties of Zn-Li-Ag alloys. The Zn-0.8Li-0.5Ag alloy exhibited the highest ultimate tensile strength (>530 MPa). Zn-Li-Ag alloys showed strong bactericidal effects on methicillin-resistant Staphylococcus aureus (MRSA) in vitro. RNA sequencing revealed two MRSA-killing mechanisms exhibited by the Zn-0.8Li-0.5Ag alloy: cellular metabolism disturbance and induction of reactive oxygen species production. To verify that the therapeutic potential of the Zn-0.8Li-0.5Ag alloy is greater than that of Ti intramedullary nails, X-ray, micro-computed tomography, microbiological, and histological analyses were conducted in a rat femoral model of MRSA-induced osteomyelitis. Treatment with Zn-0.8Li-0.5Ag alloy implants resulted in remarkable infection control and favorable bone retention. The in vivo safety of this ternary alloy was confirmed by evaluating vital organ functions and pathological morphologies. We suggest that, with its good antibacterial and osteogenic properties, Zn-0.8Li-0.5Ag alloy can serve as an orthopedic implant material to prevent and treat orthopedic implant-related infections.

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Bone defects are commonly caused by severe trauma, malignant tumors, or congenital diseases and remain among the toughest clinical problems faced by orthopedic surgeons, especially when of critical size. Biodegradable zinc-based metals have recently gained popularity for their desirable biocompatibility, suitable degradation rate, and favorable osteogenesis-promoting properties. The biphasic activity of Sr promotes osteogenesis and inhibits osteoclastogenesis, which imparts Zn-Sr alloys with the ideal theoretical osteogenic properties. Herein, a biodegradable Zn-Sr binary alloy system was fabricated. The cytocompatibility and osteogenesis of the Zn-Sr alloys were significantly better than those of pure Zn in MC3T3-E1 cells. RNA-sequencing illustrated that the Zn-0.8Sr alloy promoted osteogenesis by activating the wnt/ß-catenin, PI3K/Akt, and MAPK/Erk signaling pathways. Furthermore, rat femoral condyle defects were repaired using Zn-0.8Sr alloy scaffolds, with pure Ti as a control. The scaffold-bone integration and bone ingrowth confirmed the favorable in vivo repair properties of the Zn-Sr alloy, which was verified to offer satisfactory biosafety based on the hematoxylin-eosin (H&E) staining and ion concentration testing of important organs. The Zn-0.8Sr alloy was identified as an ideal bone repair material candidate, especially for application in critical-sized defects on load-bearing sites due to its favorable biocompatibility and osteogenic properties in vitro and in vivo.

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Ultra-wideband (UWB), a radio transmission technology with wide bandwidth exceeding the minimum of 500 MHz or at least 20% of the center frequency, is a revolutionary approach for short-range high-bandwidth wireless communication. In this study, carbon nanotube (CNT) UWB antennas by direct laser-patterning technology have been successfully designed, fabricated and characterized. In contrast with traditional fabrication methods, the direct laser-patterning technology offers an exceptional potential for custom-designed, high-complexity and accuracy device fabrication. The "engraving" process on CNTs exposed to laser can be attributed to the bond breaking of C-C, evaporation of carbon atoms, and oxidation of CNTs by the oxygen molecules. Numerical analysis and experimental studies provide characteristics of CNT slot antennas with a wide impedance bandwidth (from 3.4 GHz to 14 GHz for S11 ≤ -10 dB), high average radiation efficiency (76%) and fractional bandwidth (121%) with small size of 30 × 30 mm2. The results indicate the advantages of laser-patterned UWB antennas based on carbon nanotubes, which paves the way for industrial applications, particularly in the world of consumer electronics.

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The transition from the current 4th generation mobile networks (4G) to the next generation, known as 5th generation mobile networks (5G), is expected to occur within the next decade. To provide greater network speed, capacity and better coverage, the wireless broadband technologies need to update traditional antennas for high frequency and millimeter wavelengths. In this study, meander line dipole antennas produced by direct ink-injecting technology have been successfully designed, fabricated and characterized, where the ink-injecting technology may open new routes to the fabrication of wireless antenna applications. An accurate electromagnetic numerical analysis model for the proposed meander line antenna is also developed. The designed dual-band antenna based on graphene flakes and Ag nanowires can operate from 1.2 GHz up to the 1.5 GHz band and from 3.2 GHz up to the 3.8 GHz band with |S 11| > 10 dB for wireless communications applications. Different mixtures by mass ratio of aqueous dispersions of CNTs and Ag nanowires (1 : 1, 5 : 1, 10 : 1, 20 : 1) are also prepared to investigate the influence of the network structure on the performance of the meander line antennas.

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