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Based on the thread tooth load distribution of the inverted planetary roller screw mechanism（IPRSM）, the influence of roller modification and screw modification on the load distribution is analyzed. The results show that the uneven load on the screw-roller interface is more serious than that on the long nut-roller interface, and the maximum contact stress and the maximum load on the threaded teeth are effectively reduced by the roller modification. Besides, the long nut-roller interface is more sensitive to the modification amount than that of the screw-roller interface. Similarly, the maximum load can also be effectively reduced by the screw modification. This study has some reference significance for optimizing the load distribution of the IPRSM.

Bone and skeletal muscle work in coordination to maintain the function of the musculoskeletal system, in which skeletal muscle contraction drives the movement of the bone lever system while bone provides insert sites for skeletal muscle through the bone-muscle junction. Existing evidence suggests that factors secreted by skeletal muscle and bone mediate the interaction between the two tissues. Herein, we focused on the relationship between skeletal muscle and bone and the underlying mechanism of the interaction. Exercise can promote bone strength and secrete osteocalcin and insulin-like growth factor I into the blood, thus improving muscle quality. In addition, exercise can also promote myostatin, interleukin-6, Irisin, and apelin in muscles to enter the blood so that they can act on bones to maintain the balance between bone absorption and bone formation. There is a special regulatory axis interleukin-6/osteocalcin between myokines and osteokines, which is mainly influenced by exercise. Therefore, we pay attention to the important factors in the bone-muscle intersection that are affected by exercise, which were found or their functions were expanded, which strengthened the connection between organs of the whole body, highlighting the importance of exercise and contributing to the diagnosis, prevention, and treatment of osteoporosis and sarcopenia in the clinic.

ObjectivesTo investigate neonatal electroencephalography (EEG) background activity and electrographic seizures in patients in the pediatric intensive care unit (PICU) who underwent bedside video-electroencephalography (vEEG) monitoring.MethodsA total of 232 pediatric patients admitted or transferred to PICU that underwent vEEG monitoring were retrospectively enrolled in this study, and electrographic status epilepticus was observed after vEEG monitoring.ResultsThe median age was 1.56 years [95% confidence interval (CI) = 1.12–2.44]. Electrographic seizures occurred in 88 patients (37.9%), out of which 36 cases (40.9%) had electrographic status epilepticus. Prior epileptic encephalopathy diagnosis [odds ratio (OR) = 6.57, 95% CI = 1.91–22.59, p = 0.003], interictal epileptiform discharges (OR = 46.82, 95%CI = 5.31–412.86, p = 0.0005), slow disorganized EEG background (OR = 11.92, 95%CI = 1.31–108.71, p = 0.028), and burst-suppression EEG background (OR = 23.64, 95%CI = 1.71–327.57, p = 0.018) were the risk factors for electrographic seizures' occurrence. Of the 232 patients, the condition of 179 (77.2%) patients improved and they were discharged, 34 cases (14.7%) were withdrawn, and 18 cases (7.8%) died. The in-hospital death rate was 47.6% (10 in 21 cases) in patients with attenuated/featureless, compared to 0/23 with normal EEG background.ConclusionsElectrographic status epilepticus occurs in more than one-third of patients with electrographic seizures. vEEG is an efficient method to determine electrographic seizures in children. Abnormal EEG background activity is associated with both electrographic seizures' occurrence and unfavorable in-hospital outcomes.

Purpose: To assess the optimal planning target volume (PTV) margins for stereotactic body radiotherapy (SBRT) of prostate cancer based on inter- and intra-fractional prostate motion determined from daily image guidance. Methods and Materials: Two hundred and five patients who were enrolled on two prospective studies of SBRT (8 Gy × 5 fractions) for localized prostate cancer treated at a single institution between 2012 and 2017 had complete inter- and intra-fractional shift data available. All patients had scheduled kilovoltage planar imaging during SBRT with rigid registration to intraprostatic fiducials prior to each of four half-arcs delivered per fraction, as well as cone beam CT verification of anatomy prior to each fraction. Inter- and intra- fractional shift data were obtained to estimate the required PTV margins based on the classic van Herk formula. Inter- and intra-fractional motion were compared between patients with and without severe toxicities using the independent two-sample Wilcoxon test. Results: The margins required to account for inter-fractional motion were estimated to be 0.99, 1.52, and 1.45 cm in lateral (LR), longitudinal (SI), and vertical (AP) directions, respectively. The margins required to account for intra-fractional motion were estimated to be 0.19, 0.27, and 0.31 cm in LR, SI and AP directions, respectively. Large intra-fractional shifts were mostly observed in the SI and AP directions, with 2.0 and 5.4% of patients experiencing average intra-fractional motion >3 mm in the SI and AP directions, respectively, compared with none experiencing mean shifts >3 mm in the LR direction. Six patients experienced grade 3 gastrointestinal or genitourinary toxicity. There were no significant differences in mean inter- or intra-fractional motion in any of the cardinal directions compared to patients without severe toxicity (inter-fractional p = 0.46-0.99, intra-fractional p = 0.10-0.84). Conclusion: The inter- and intra-fractional margins estimated from this study are in line with prior reported values. Intra-fractional prostate motion was generally small with larger margins required for the SI and AP directions, notably just slightly exceeding the commonly used 3 mm posterior PTV margin even with realignment between half-arcs. Development of severe toxicity was not significantly associated with the degree of inter- or intra-fractional motion.

Inflammation plays an important role in nerve defects caused by intracerebral hemorrhage. Repairing brain damage by inhibiting the macrophage-inducible C-type lectin/spleen tyrosine kinase (Mincle/Syk) signaling pathway is a potential new target for treating cerebral hemorrhage. In this study, we aimed to determine whether acupuncture through Baihui (DU20) to Qubin (GB7) is an effective treatment for intracerebral hemorrhage through the Mincle/Syk signaling pathway. An intracerebral hemorrhage rat model was established by autologous blood infusion into the caudate nucleus. Acupuncture through Baihui to Qubin was performed for 30 minutes, once every 12 hours, for a total of three times. Piceatannol (34.62 mg/kg), a Syk inhibitor, was intraperitoneally injected as a control. Modified neurological severity score was used to assess neurological function. Brain water content was measured. Immunohistochemistry and western blot assay were used to detect immunoreactivity and protein expression levels of Mincle, Syk, and CARD9. Real-time polymerase chain reaction was used to determine interleukin-1β mRNA levels. Hematoxylin-eosin staining was performed to observe histopathological changes. Our results showed that acupuncture through Baihui to Qubin remarkably improved neurological function and brain water content, and inhibited immunoreactivity and expression of Mincle, Syk, CARD9, and interkeukin-1β. Moreover, this effect was similar to piceatannol. These findings suggest that acupuncture through Baihui to Qubin can improve neurological impairment after cerebral hemorrhage by inhibiting the Mincle/Syk signaling pathway.

Ni–P(–SiC) composite coatings were successfully deposited on 70 vol% SiCp/Al composite by electroless plating. The surface microstructures and the phase structures of the Ni–P(–SiC) coatings were examined and analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD) before and after heat-treatment at 200–400 °C for 2 h. The thermal diffusivity of the deposited samples and the interface adhesion between the coating and the substrate were investigated. The experimental results show that SiC content in the coatings increases obviously and XRD peaks are enhanced with SiC content in the bath increasing from 3 to 9 g·L−1. After heat-treatment, the surface of the coating becomes smoother and no diffusion layer is produced at the interface. A new phase Ni3P forms in the coating during heat-treatment at 400 °C. The critical load (Lc) of Ni–P–SiC composite coating on SiCp/Al composite reaches the maximum value of 84.9 N with SiC content of 3 g·L−1 after heat-treatment at 200 °C and more or less decreases with the increase in SiC content and heat-treatment temperature. The thermal diffusivity of deposited samples gradually increases as the temperature increases; however, it reduces firstly and then climbs with the increase in SiC content. [ABSTRACT FROM AUTHOR]