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This study investigated the corrosion resistance and mechanical properties of Mg-2Zn-0.46Y-0.5Nd (wt.%) alloy plates and screws with fluorinated coatings and atomic layer deposition (ALD)-derived zirconia (ZrO2) coatings in vitro under physiological stress conditions. Synthetic polyurethane hemimandible replicas were split and fixed as the following three groups of magnesium alloy plates and screws: no additional surface coating treatment (Group A), with fluorinated coatings (Group B), and with duplex fluorinated and ALD-derived 100 nm ZrO2 coatings (Group C). A circulating stress of 1–10 N was applied to the distal bone segment, and a 4-week simulated body fluid immersion test was employed to study the remaining material volume and the mechanical properties of the different groups. Compared with Group A and Group B, the degradation rate of magnesium alloy plates and screws' head regions was significantly slowed down under the protection of duplex MgF2/ZrO2 coatings (p < 0.01). There was no significant difference in the degradation rate of the screw shaft region between groups (p = 0.077). In contrast to fluoride coatings, duplex MgF2/ZrO2 coatings maintained the mechanical strength of magnesium alloy plates and screws after a 14 day in vitro SBF immersion test. We conclude that duplex MgF2/ZrO2 coatings exhibited a certain protective effect on the Mg alloy plates and screws under physiological stress conditions. [ABSTRACT FROM AUTHOR]

Summary: Brassinosteroids (BRs) play a crucial role in shaping the architecture of rice (Oryza sativa) plants. However, the regulatory mechanism of BR signalling in rice immunity remains largely unexplored. Here we identify a rice mutant dla, which exhibits decreased leaf angles and is insensitive to 24‐epiBL (a highly active synthetic BR), resembling the BR‐deficient phenotype. The dla mutation caused by a T‐DNA insertion in the OsDLA gene leads to downregulation of the causative gene. The OsDLA knockout plants display reduced leaf angles and less sensitivity to 24‐epiBL. In addition, both dla mutant and OsDLA knockout plants are more susceptible to rice blast compared to the wild type. OsDLA is a GRAS transcription factor and interacts with the BR signalling core negative regulator, GSK2. GSK2 phosphorylates OsDLA for degradation via the 26S proteasome. The GSK2 RNAi line exhibits enhanced rice blast resistance, while the overexpression lines thereof show susceptibility to rice blast. Furthermore, we show that OsDLA interacts with and stabilizes the WRKY transcription factor OsWRKY53, which has been demonstrated to positively regulate BR signalling and blast resistance. OsWRKY53 directly binds the promoter of PBZ1 and activates its expression, and this activation can be enhanced by OsDLA. Together, our findings unravel a novel mechanism whereby the GSK2‐OsDLA‐OsWRKY53 module coordinates blast resistance and plant architecture via BR signalling in rice. [ABSTRACT FROM AUTHOR]

A fast and efficient method is proposed in this letter to characterize the dielectric permittivity of thin‐film materials. The measuring system is based on a TE103 rectangular split‐cavity resonator operating at around 10 GHz, which has the advantage of providing nondestructive measurements while maintaining a high level of accuracy. The thin‐film materials under test can be directly inserted in the split without being processed in a specific shape. Different dielectric materials are tested using this method. And the theoretical derivations and experimental measurements have been performed to confirm the validity and effectiveness of this approach. [ABSTRACT FROM AUTHOR]

A design of planar dual‐polarized differentially fed multibeam patch antenna array (DFMPAA) is presented in this article. The dual‐polarized DFMPAA is composed of two circular 4 × 4 butler matrixs (BMs) and a 1 × 4 dual‐polarized patch antenna array. The two BMs are designed in the top and bottom layer as the feeding network of horizontal polarization (HP) and vertical polarization (VP), respectively. The patch is designed as the radiation element of the dual‐polarized DFMPAA, which is fed by the slot and aperture coupling to generate the HP and VP wave, respectively. To achieve high cross‐polarization discrimination (XPD), the antenna element is fed differentially. A prototype working at 5.5 GHz is fabricated and measured in order to validate the performance of the proposed dual‐polarized DFMPAA. The dimension of the dual‐polarized DFMPAA is 3.8 λ0 × 1.7 λ0. Measured results show that when the beam scan to the maximal pointing angle, the XPD of the dual‐polarized DFMPAA in HP and VP are higher than 27 and 29 dB, respectively. Additionally, the beams of the dual‐polarized DFMPAA can cover the range of ±42° in horizontal plane. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study is to compare the short- and long-term reproducibility of verbal and nonverbal facial expressions of normal people using dynamic 3-dimensional (3-D) imaging. Design: Prospective, cross-sectional, controlled study. Setting: Peking University School and Hospital of Stomatology, Beijing, China. Patients and Participants: Twenty-seven participants, 12 males and 15 females, were recruited for this study. Methods: A 3-D dynamic system was applied to capture the process of 4 nonverbal facial expressions (smile lips closed, smile lips open, lip purse, cheek puff) and 2 verbal facial expressions (/i:/, /u:/) at an initial time point, 15 minutes later, and 1 week later. Key frames were selected from each expression recording sequence. Main Outcome Measures: The root mean square (RMS) between each key frame and its corresponding frame at rest was calculated. ΔRMS reflected the difference of the same key frames between the different sessions of the same expression of the same participant. The reproducibility of different facial expressions at different time intervals were analyzed. Results: There was no significant difference in verbal and nonverbal expression repeatability during a 15-minute interval, except for cheek puff motion. Following a 1-week interval, verbal expression repeatability was superior to that of nonverbal expressions (P <.01). Compared with nonverbal expressions, the repeatability of verbal expressions did not obviously decrease with the increase in recording interval. Conclusions: Dynamic 3-D imaging is a useful technique for facial expression analysis. Verbal expressions showed greater reproducibility than nonverbal expressions. [ABSTRACT FROM AUTHOR]

Lesion mimic mutants constitute a valuable genetic resource for unraveling the signaling pathways and molecular mechanisms governing the programmed cell death and defense responses of plants. Here, we identified a lesion mimic mutant, spl-D , from T-DNA insertion rice lines. The mutant exhibited higher accumulation of H2O2, spontaneous cell death, decreased chlorophyll content, up-regulation of defense-related genes, and enhanced disease resistance. The causative gene, OsGRDP1 , encodes a cytosol- and membrane-associated glycine-rich domain protein. OsGRDP1 was expressed constitutively in all of the organs of the wild-type plant, but was up-regulated throughout plant development in the spl-D mutant. Both the overexpression and knockdown (RNAi) of OsGRDP1 resulted in the lesion mimic phenotype. Moreover, the intact-protein level of OsGRDP1 was reduced in the spotted leaves from both overexpression and RNAi plants, suggesting that the disruption of intact OsGRDP1 is responsible for lesion formation. OsGRDP1 interacted with an aspartic proteinase, OsAP25. In the spl-D and overexpression plants, proteinase activity was elevated, and lesion formation was partially suppressed by an aspartic proteinase inhibitor. Taken together, our results reveal that OsGRDP1 is a critical feedback regulator, thus contributing to the elucidation of the mechanism underlying cell death and disease resistance. [ABSTRACT FROM AUTHOR]

The utilization of guided tissue regeneration membranes is a significant approach for enhancing bone tissue growth in areas with bone defects. Biodegradable magnesium alloys are increasingly being used as guided tissue regeneration membranes due to their outstanding osteogenic properties. However, the degradation rates of magnesium alloy bone implants documented in the literature tend to be rapid. Moreover, many studies focus only on the initial 3-month period post-implantation, limiting their applicability and impeding clinical adoption. Furthermore, scant attention has been given to the interplay between the degradation of magnesium alloy implants and the adjacent tissues. To address these gaps, this study employs a well-studied magnesium-aluminum (Mg-Al) alloy membrane with a slow degradation rate. This membrane is implanted into rat skull bone defects and monitored over an extended period of up to 48 weeks. Observations are conducted at various intervals (2, 4, 8, 12, 24, and 48 weeks) following the implantation. Assessment of degradation behavior and tissue regeneration response is carried out using histological sections, micro-CT scans, and scanning electron microscopy (SEM). The findings reveal that the magnesium alloy membranes demonstrate remarkable biocompatibility and osteogenic capability over the entire observation duration. Specifically, the Mg-Al alloy membranes sustain their structural integrity for 8 weeks. Notably, their osteogenic ability is further enhanced as a corrosion product layer forms during the later stages of implantation. Additionally, our in vitro experiments employing extracts from the magnesium alloy display a significant osteogenic effect, accompanied by a notable increase in the expression of osteogenic-related genes. Collectively, these results strongly indicate the substantial potential of Mg-Al alloy membranes in the context of guided tissue regeneration.

Objective: The aim of this study is to compare the short- and long-term reproducibility of verbal and nonverbal facial expressions of normal people using dynamic 3-dimensional (3-D) imaging., Design: Prospective, cross-sectional, controlled study., Setting: Peking University School and Hospital of Stomatology, Beijing, China., Patients and Participants: Twenty-seven participants, 12 males and 15 females, were recruited for this study., Methods: A 3-D dynamic system was applied to capture the process of 4 nonverbal facial expressions (smile lips closed, smile lips open, lip purse, cheek puff) and 2 verbal facial expressions (/i:/, /u:/) at an initial time point, 15 minutes later, and 1 week later. Key frames were selected from each expression recording sequence., Main Outcome Measures: The root mean square (RMS) between each key frame and its corresponding frame at rest was calculated. ΔRMS reflected the difference of the same key frames between the different sessions of the same expression of the same participant. The reproducibility of different facial expressions at different time intervals were analyzed., Results: There was no significant difference in verbal and nonverbal expression repeatability during a 15-minute interval, except for cheek puff motion. Following a 1-week interval, verbal expression repeatability was superior to that of nonverbal expressions ( P < .01). Compared with nonverbal expressions, the repeatability of verbal expressions did not obviously decrease with the increase in recording interval., Conclusions: Dynamic 3-D imaging is a useful technique for facial expression analysis. Verbal expressions showed greater reproducibility than nonverbal expressions.