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[Objective] In the background of the increasing trend of non-grain production in hilly and mountainous areas of China, it is of great practical significance to explore the mechanism of the farmland suitability for agricultural machinery operation (FSAM) on the mitigation of non-grain production and empirically measure its specific impact degree. [Methods] This paper constructed farmer’s production decision-making model, which based on profit maximization constraints, and derived the influence mechanism. This paper used the national agricultural mechanization survey data organized by the Agricultural Mechanization Management Department of the Ministry of Agriculture and Rural Affairs from May to July 2020, measured the degree of FSAM from three perspectives of plot size, plot flatness and plot accessibility, to empirically measure the mitigation degree of FSAM to non-grain production in hilly and mountainous areas of China. [Results] It is found that: (1) Against the backdrop of rapidly rising labor costs, mature mechanization technology for grain crops, and lagging mechanization technology for non-grain crops, enhancing FSAM can effectively reduce the degree of non-grain farming among farmers. (2) The transmission path for reducing the degree of non-grain farming through improving FSAM is as follows: Enhanced FSAM lowers the price of agricultural machinery factors, prompting farmers to increase the level of agricultural mechanization for replacing labor with cheaper agricultural machinery factors. Given the immaturity of mechanization technology for non-grain crops, farmers opt to plant more grain crops, thereby reducing the degree of non-grain farming. (3) There exists scale heterogeneity in the impact of FSAM on non-grain farming, meaning that compared to small-scale farmers, the degree of farmland suitability for mechanization has a more significant impact on the degree of non-grain farming among large-scale farmers. [Conclusion] On the whole, the high degree of FSAM operations can effectively reduces the cost of agricultural machinery in grain production, promotes labor substitution and cost reduction in grain production, and helps to alleviate the problem of non-grain production in hill and mountain areas of China, and thus ensures food security.

[Introduction] In order to solve the problem of changing the external steam supply of the unit from industrial steam to heating steam , a thermal power plant is taken as an object to carry out technical feasibility study. [Method] Four kinds of schemes including the control valve group, the two-cylinder steam turbine, the post-unit back pressure steam turbine shared by the whole plant, and the steam-driven feed water pump unit with generator were compared and analyzed. [Result] Considering the characteristics of the schemes and project practice, the scheme of post-unit back pressure steam turbine shared by the whole plant is selected. [Conclusion] The scheme is based on the principle of energy level cascade utilization, which is reliable in operation and economical. It also provides a useful reference for the comprehensive steam supply transformation of subsequent units.

Objective Hemodynamic instability is the main factor in the development of intraventricular hemorrhage (IVH) in preterm infants. The purpose of this study is to evaluate the predictive value of blood pressure variability (BPV) and anterior cerebral artery (ACA) blood flow parameters in IVH in preterm infants with gestational age -32 weeks and birth weight -1 500 g. Methods Preterm infants with gestational age -32 weeks and birth weight - 1500 g admitted to the neonatal intensive care unit (NICU) were selected as the research subjects. All preterm infants were admitted within 1 hour after birth, and systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial blood pressure (MABP) were monitored every 1 hour interval. The difference between maximum and minimum values (max-min), standard deviation (SD), coefficient of variation (CV), and successive variation (SV) were used as BPV indicators. On the 1st, 3rd, and 7th day of admission, transcranial ultrasound examination was performed to screen for the occurrence of IVH. On the 1st day, systolic velocity (Vs), diastolic velocity (Vd), and resistance index (RI) of ACA were measured simultaneously. Preterm infants were divided into IVH group and non IVH group based on the results of transcranial ultrasound examination, and the correlation between BPV indicators, ACA blood flow parameters, and the development of IVH was analyzed. Results A total of 92 preterm infants met the inclusion criteria, including 49 in the IVH group and 43 in the non IVH group. There was no statistically significant difference in baseline characteristics such as gestational age, birth weight, gender, and perinatal medical history between the two groups of preterm infants (P > 0.05). SBP SD (OR = 1.480 95% CI: 1.020 - 2.147), and ACA-RI (OOR = 3.027 95% CI: 2.769 - 3.591) are independent risk factors for IVH in preterm infants. The sensitivity and specificity of combined detection of SBP SD, and ACA-RI in predicting IVH were 61.2% and 79.1%, respectively. Conclusion High BPV and ACA-RI are related to IVH in preterm infants with gestational age -32 weeks and birth weight - 1 500 g. Combined detection of SBP SD, and ACA-RI has a certain predictive effect on early identification of IVH. [ABSTRACT FROM AUTHOR]

The fault early warning model for centrifugal blowers established by laboratory data become invalid when used in factories. And data collecting there was difficult to build high-precision model. To address this problem, this paper proposed a transfer learning method based on AE, which had ability to build the fault early warning model suitable for factory environments quickly. Firstly, the monitoring data of centrifugal blowers collected in the laboratory was windowed resampled to establish an AE model with sparse constraints. Secondly, the factory and laboratory data were input into the AE network to obtain low-dimensional features, and the maximum mean discrepancy (MMD) between the two low-dimensional features was minimized, then the AE model with small learning rate was fine-tuned to complete the transfer of AE model. Finally, based on the trained AE model and early warning indicator, the fault early warning strategy was formulated to realize fault early warning for centrifugal blowers under the actual environments of the factories. The experimental results on a centrifugal blower show that the proposed method has higher accuracy compared with other three methods. [ABSTRACT FROM AUTHOR]

Objective To evaluate the effect of clinical pathway model in clinical teaching for pediatric nursing students. Methods Totally 100 nursing students participating in the pediatric clinical practice were assigned to the observation group and the control group, with 50 cases in each group. The conventional teaching method was used for students in the control group, and the clinical pathway model was adopted in clinical teaching for students in the observation group. Outcomes of examination on theory knowledge and practice skills were compared between two groups. The students' satisfaction on clinical teaching was evaluated. Results Students in the observation group achieved higher scores of theory knowledge and practice skills assessment compared with those in the control group (P < 0. 01). Students in the observation group received higher ratings by clinical teachers compared with those in the control group (P <0.01). Nursing students in the observation group were more satisfied with the teaching methods compared with those in the control group (P <0.05). Conclusion The clinical pathway model is effective to improve the teaching efficacy and satisfaction both clinical teachers and pediatric nursing students. [ABSTRACT FROM AUTHOR]

Objective: To study the risk factors contributing to the development of hypertension in patients with obstructive sleep apnoea hypopnea syndrome (OSAHS), and the clinical characteristics of OSAHS with hypertension., Methods: A total of 2397 OSAHS patients aged above 30 years old and diagnosed by the sleep-disordered breathing center of Guangxi between July 2012 and August 2015 were recruited. OSAHS patients with new-onset hypertension (OSAHS with hypertension group) and those without hypertension (simple OSAHS group) were identified and their clinical data, including general status, family history of hypertension or snoring, Epworth Sleepiness Scale (ESS) score for daytime sleepiness, physical examination findings, and polysomnography monitoring data were collected. OSAHS patients with new-onset hypertension (n=101) and OSAHS patients without hypertension (n=202) matched by age and body mass index (BMI) (age difference, 2 years; BMI difference, 1.5 kg/m(2)) were recruited in the OSAHS with hypertension group and the simple OSAHS group. A case-control study was used to compare the clinical characteristics of these two groups, and univariate and multivariate Logistic regression were used to analyze all the factors contributing to hypertension development besides age and BMI., Results: The average age and BMI of the OSAHS with hypertension group and the simple OSAHS group were respectively (46.2±9.3), (46.2±9.2) years old and (28.2±2.8), (28.2±2.8) kg/m(2). Patients in the two groups were well-matched with respect to age and BMI (P>0.05). The systolic blood pressure (SBP) and diastolic blood pressure (DBP) in the OSAHS with hypertension group were significantly higher than those in the simple OSAHS group at the first admission to the clinic and before and after the PSG examination. ESS values in the OSAHS with hypertension group and the simple OSAHS group were respectively 10.0±6.4 and 9.2±6.3 (P>0.05). There was no significant intergroup difference in neck circumference, waist circumference, duration of snoring, family history of snoring, and family history of hypertension (P>0.05) either. The apnea-hypopnea index (AHI) and apnea index (AI) in the OSAHS with hypertension group were higher than those in the simple OSAHS group (P<0.05); the longest apnea duration (LAD), mean apnea duration (MAD), and the total time spent with oxygen saturation below 90% (T90%) in the OSAHS with hypertension group were significantly longer than those in the simple OSAHS group (P<0.05). The minimal pulse oxygen saturation (MinSpO2) in the OSAHS with hypertension group was significantly lower than that in the simple OSAHS group (P<0.05). Six factors were identified to be associated with OSAHS with hypertension through univariate analysis: AHI (OR=0.985, P=0.001), AI (OR=0.983, P<0.001), LAD (OR=0.955, P=0.013), MAD (OR=0.874, P=0.015), MinSpO2 (OR=0.874, P=0.015), T90% (OR=0.997, P=0.036). Only MinSpO2 (P<0.001, OR=0.894) was closely related to OSAHS hypertension development in the multivariate Logistic regression model., Conclusions: OSAHS patients with hypertension may show lower MinSpO2, higher AHI and AI, and longer LAD, MAD, and T90% than OSAHS patients without hypertension. MinSpO2 is probably closely related to OSAHS hypertension development.

Objective: To explore the correlation between smoking and obstructive sleep apnea and hypopnea syndrome (OSAHS)., Methods: The data were collected from a chart review of patients with sleep or sleep-breathing disorders undergoing overnight polysomnography (PSG) at Sleep-Disordered Breathing Center of Guangxi from July 1, 2009 to June 30, 2012. Smoking history was quantified by retrospective questionnaires. A definite diagnosis of OSAHS was defined by an apnea-hypopnea index (AHI) (events/h) of > 15 events per hour. And those with AHI (events/h) between 5 and 15 were eliminated. The non-OSAHS subjects were defined by an AHI (events/h) <5 events per hour. The association of smoking status and severity with OSAHS was analyzed., Results: A total of 903 patients were excluded from 2 243 patients. The recruited subjects were divided into OSAHS (n = 929) and non-OSAHS (n = 411) groups. Smoking prevalence in OSAHS group was 47.1% versus 25.5% in non-OSAHS group. Logistic regression analyses were performed to examine the effects of smoking habits while adjusting for age, gender, body mass index (BMI) and drinking history. Current smokers were 1.446 times more likely to have OSAHS than non-smokers (95% CI: 1.079-1.939, P = 0.013). Current smokers with pack-years ≥ 30 were more 2.382 times more likely to have OSAHS than non-smokers to have OSAHS (95% CI: 1.127-4.375, P = 0.012). Current smokers diagnosed as having OSAHS with pack-years ≥ 30 had a more percentage of total sleep time (TST) spent with saturation of oxyhemoglobin (SaO₂)<90% ((20.5 ± 23.1)% vs (15.6 ± 18.8)%, P = 0.004) and lower average SaO₂ ((69.4 ± 10.3)% vs (73.2 ± 9.7)%, P = 0.000) during sleep than non-smokers diagnosed as having OSAHS. Current smokers diagnosed as having OSAHS with pack-years ≥ 30 were 1.893 times more likely to spend > 5% of TST at SaO₂<90% than non-smokers diagnosed as having OSAHS (95% CI: 1.046-3.423, P = 0.035)., Conclusions: Smoking is associated with a significantly increased risk of OSAHS and nocturnal hypoxia in current smokers, especially those with ≥ 30 pack-years. And it exacerbates nocturnal hypoxia in OSAHS patients.

Brain atlas provides a spatial reference system on which other images can be interpreted in a consistent way, and it is essential for the brain imaging research. However, because of the differences in structure between occidental and oriental brains, the brain atlas based on Western populations, e. g., the International Consortium for Brain Mapping's 154 T1 Weighted Average Atlas, may not be appropriate for other ethnic groups. Therefore, in the present study, we produce an average brain atlas which is based on the data collected from 100 healthy Chinese volunteers. The differences in brains between the Chinese population and the Western population were also investigated. Comparatively,Chinese brains are wider and shorter in size, and smaller in volume.