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The piezoelectric stick-slip stage is very important in industrial manufacturing and precision machining. However, due to the stick-slip principle, it is inevitable to produce backward motion, which leads to a decrease in precision and efficiency. A novel smooth-drive scheme for piezoelectric stage is proposed by coupling stick-slip motion and inertial impact in this paper. In the coupling counteract phase, the sliding friction force of stick-slip driving mechanism (SDM) is counteract by the impact force of inertial impact driving mechanism (IDM), thus eliminating the backward motion and realizing the smooth driving of the stage. The feasibility of the stage is analyzed by theoretical calculation and transient dynamics simulation. In addition, the designed stage is fabricated and conducted a complete set of experimental tests. The external dimensions of the stage is 45 mm (L) × 24 mm (W) × 22 mm (H), and the mass is 84 g. Experimental results show that the piezoelectric stage can not only achieve smooth driving, but also actively adjust the output smoothness by adjusting the excitation voltage of PZT I and PZT II. The linear fitting correlation coefficient R2 of the displacement curve can reach above 0.999, and it still keeps good smoothness at 200 Hz. The maximum vertical mass load of the stage is 4 kg, which is about 47 times the mass of the stage, and the resolution of stick-slip state is about 85 nm. The scheme has positive reference value in the field of stable and accurate positioning.

Background Endometrial cancer (EC) is a common gynecological tumor in females with an increasing incidence over the past few decades. Alcohol consumption has been linked to the occurrence of various cancers; however, epidemiological studies have shown inconsistent associations between alcohol consumption and EC risk. This study aimed to investigate whether there is a causal relationship between alcohol consumption and EC.Methods Mendelian randomization (MR) analysis was conducted using publicly available summary-level data from genome-wide association studies (GWAS). Fifty-seven single nucleotide polymorphisms (SNPs) were extracted as instrumental variables for alcohol exposure from the Social Science Genetic Association Consortium (SSGAC) GWAS summary data involving 941,287 participants of European ancestry. SNPs for EC were obtained from the Endometrial Cancer Association Consortium, the Endometrial Cancer Epidemiology Consortium, and the UK Biobank, involving 121,885 European participants. The inverse variance weighted (IVW) method was used as the primary method to estimate the causal effect, and the MR-Egger regression and weighted median method were used as supplementary methods. Sensitivity analyses were conducted using the Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO) global test, MR-Egger intercept test, and leave-one-out analysis to evaluate the impact of pleiotropy on causal estimates.Results An increase of 1 standard deviation (SD) of genetically predicted log-transformed alcoholic drinks per day was associated with a 43% reduction in EC risk (odds ratio [OR], 0.57; 95% confidence interval [CI], 0.41–0.79; P༜0.001). Subgroup analysis of EC revealed that alcohol consumption was a protective factor for endometrioid endometrial cancer (EEC) (OR, 0.56; 95% CI, 0.38–0.83; P = 0.004) but not for non-endometrioid endometrial cancer (NEC) (OR, 1.36; 95% CI, 0.40–4.66; P = 0.626). The MR-Egger regression and weighted median method yielded consistent causal effects with the IVW method. The consistent results of sensitivity analyses indicated the reliability of our causal estimates. Additionally, alcohol consumption was associated with decreased human chorionic gonadotropin (HCG) and insulin-like growth factor 1 (IGF1) levels.Conclusion This study suggests that alcohol consumption is a protective factor for EC, particularly for EEC, and this protective effect may be mediated through the reduction of HCG and IGF1.

Purpose: To investigate the effect of application of tiotropium bromide and N- acetylcysteine in combination with respiratory training on the treatment of patients with chronic obstructive pulmonary disease (COPD), and the effect of the combined treatment on pulmonary function, tolerance of physical activity, and quality of life.Methods: One hundred COPD patients admitted to The First People’s Hospital of Guiyang (February 2019 - March 2021) were randomly and equally assigned to groups X and Y. Patients in Y were given tiotropium bromide in combination with N-acetylcysteine, while group X was treated with respiratory training, in addition to the treatment regimen in Y. Treatment efficacy, incidence of adverse reactions, pulmonary function indices, activity tolerance, quality of life (QLI) score, activities of daily living (ADL) score, and incidence of COPD at 2 weeks, 1 month and 2 months after treatment were determined, and compared between the two groups.Results: Relative to group Y, group X had significantly higher treatment efficacy, QLI score and ADL score (p < 0.05). Furthermore, group X also had better pulmonary function indices and activity tolerance, lower incidence of adverse reactions, and lower COPD incidence at 2 weeks, 1 month and 2 months after treatment (p < 0.05).Conclusion: Tiotropium bromide and N-acetylcysteine in combination with respiratory training enhanced therapeutic effect, pulmonary function, activity tolerance and quality of life of COPD patients.

Healthcare facilities in geological hazard-prone areas not only are responsible for local basic medical services but also are the main provider of hazard emergency rescue work. The selection of their sites is further complicated by the need to consider both the equalization of regional medical services and resource allocation and the impact of geological hazards on site safety. Shimian County in Sichuan Province, a geological disaster-prone area, was chosen as the study area. First, suitability analysis of the construction land was used to determine the site alternatives for new healthcare facilities, and an evaluation index system of construction land suitability consisting of geological hazard susceptibility, slope and aspect was established. Then, the suitability was evaluated by the Ordered Weighted Averaging (OWA) operator, and the Analytic Hierarchy Process (AHP) and the quantitative method of Regular Increasing Monotone (RIM) were used to calculate the criterion weights and order weights in the Ordered Weighted Averaging operator respectively. The suitability results were classified into five levels: high, moderate, average, barely suitable, and unsuitable. Twelve site alternatives were identified in the highly and moderately suitable areas. Finally, a comprehensive evaluation index system consisting of indices such as construction land suitability and medical service accessibility was established, the PROMETHEE II method was conducted to comprehensively evaluate the site alternatives, and ranked results for the 12 site alternatives were obtained. These ranked results were analyzed by subindexes and Graphical Analysis for Interactive Aid (GAIA) to obtain a score for each alternative index and its similarity to the alternative, which could significantly help decision-making. This study achieves reasonable and scientific site selection for healthcare facilities in geological hazard-prone areas, and the results can provide references for relevant decision-makers.

Hepatitis E virus-related acute liver failure (HEV-ALF) rapidly worsens and has a high mortality. However, no simple and specific parameters for predicting short-term mortality are available.A derivation cohort including 97 patients with HEV-ALF and another validation cohort were enrolled. Laboratory and clinical parameters were recorded. Platelet count, model for end-stage liver disease (MELD), and King's College criteria (KCC) were separately used for predicting mortality, and the levels of cytokines associated with systemic inflammation, platelet production, and platelet activation were measured.Platelet counts were significantly lower in patients with HEV-ALF, and nonsurvivors had lower platelet counts than survivors (p 0.001). Platelet count was an independent risk factor for predicting 28- and 90-day mortality in patients with HEV-ALF. The AUROC of the baseline platelet count (cutoff, 131 × 10Decreased platelet count is a simple and reliable indicator for predicting 28- and 90-day mortality in patients with HEV-ALF. Overactivation of platelets is an important risk for platelet counts decrease, and treatment aiming at platelet count recovery may be considered.

Stem cell therapy has shown great potential in treating a wide range of diseases including cancer. The real-time tracking of stem cells with high spatiotemporal resolution and stable imaging signals remains the bottleneck to evaluate and monitor therapeutic outcomes once transplanted into patients. Here, we developed a photosensitive mesenchymal stem cell (MSC) loaded with mesoporous silica-coated gold nanostars (MGNSs) integrated with indocyanine green for spatiotemporal tracking and imaging-guided photothermal therapy (PTT) in treating breast cancers. The MGNS served as a stable imaging probe with multifunctional properties for photoacoustic imaging (PAI), fluorescence imaging, and PT imaging. Owing to the excellent PT stability of MGNSs, long-term three-dimensional (3D) PAI was achieved to monitor stem cells in real time at the tumor site, while the tumor structure was imaged using 3D B-mode ultrasound imaging. PAI revealed that the photosensitive stem cells reached the widest distribution area at the tumor site post 24 h of intratumoral injection, which was further confirmed via two-dimensional (2D) PT and fluorescence imaging. With this optimal cell distribution window, in vivo studies showed that the photosensitive stem cells via both intratumoral and intravenous injections successfully inhibited breast cancer cell growth and decreased the tumor recurrence rate post PTT. Our results support that this photo-integrated platform with stable optical properties is promising to achieve real-time tracking and measure the cell distribution quantitatively with high spatiotemporal resolution for stem cell therapy.

The complete chloroplast (cp) genome of Oryza sativa L.(B810S) was 134546 bp in length in the study, which contains 149 genes including 99 coding protein genes, 41 transfer RNA genes, 8 ribosomal RNA genes and 1 non-coding region by gene annotation. A total of 20879 amino acids were encoded by this cp genome, TTT (Phe) and TTG (Leu) codon were the most frequent amino acids, whereas the ACC (Thr), GCC (Ala), CTC (Leu), and AAC (Asn) codon were the least frequent ones. The content of the four bases on the cp genome were 30.6% for A, 30.4% for T, 19.4% for C and 19.6% for G, respectively. Obviously, the A+T (61.0%) content is more higher than G+C (39.0%). The gene order and content are the same as those of previously reported cp genome of Rice. Phylogenetic analysis was implemented based on concatenated amino acid sequences of 99 protein-coding genes using Neighbor-Joining method (NJ) method. Therefore, the complete B810S cp genome provides interesting insights and valuable information that can be used to identify related species and reconstruct its phylogeny. Bangladesh J. Bot. 50(3): 895-901, 2021 (September) Special