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BackgroundNatural circulation systems are widely used in the nuclear industry for decay heat removal, post-accident containment cooling, and the cooling of radioactive waste storage facilities. Because a large number of spent fuel assemblies are densely arranged in the spent fuel pool, the spent fuel assemblies in the central area of the spent fuel pool can be approximated as having adiabatic boundary conditions. In the event of a coolant loss accident, the heat generated by the spent fuel assemblies can be exported only by the natural circulation of air.PurposeThis study aims to develop analytical models for fuel assembly natural circulation characteristics independent of the results of computational fluid dynamics (CFD) to investigate the natural circulation characteristics of spent fuel pools following a coolant loss accident.MethodsBased on the experimental results of a fuel assembly pressure drop of a full-scale pressurized water reactor (PWR), the Darcy–Forchheimer model was firstly revised to predict the pressure drop of humid air flowing through the fuel assembly. Models for the fuel assembly natural circulation flow rate and peak cladding temperature were then established, and the effects of the relative humidity of air on the models were considered. Finally, these models were applied to investigating effects of total heating power, ambient temperature, and relative humidity on the natural circulation flow rate and peak cladding temperature of the fuel assembly.ResultsThe results show that the models accurately predict the natural circulation flow rate and peak cladding temperature of the fuel assembly under different heating powers, and the errors are less than 25% and 20%, respectively, as compared with the experimental measurement values.ConclusionsThe developed models in this study can be used to study the natural circulation characteristics of full-scale PWR fuel assemblies.

Background Acute ischemic stroke (AIS) is the second leading cause of death worldwide after coronary heart disease. Acute kidney injury (AKI) is one serious complication after AIS, and homocysteine (Hcy) may be an important factor associated with kidney injury and accelerated deterioration of renal function. However, there are few studies on the relationship between Hcy and AKI, especially in patients with AIS. Objective To investigate the relationship between plasma Hcy level and AKI in patients with AIS, and to provide new ideas for the prevention and treatment of AKI. Methods Baseline clinical data of 1 202 patients with AIS who were admitted to Department of Neurology, the Second Hospital of Tianjin Medical University were collected from the electronic medical record systemfrom January 2018 to April 2021. Patients were divided into normal Hcy (Hcy≤15 μmol/L, n=618), mild hyperhomocysteinemia (HHcy) (16 μmol/L30 μmol/L, n=125) groups according to the Expert Consensus on the Diagnosis, Treatment, and Prevention of Hyperhomocysteinemia. Patients were divided into AKI group and non-AKI group by the values of ambulatorily monitored renal function and urine volume within seven days after admission recommended in the KDIGO 2021 Clinical Practice Guideline for the Management of Glomerular Diseases. Multivariate Logistic regression was used to explore the effects of Hcy on post-AIS AKI as a continuous variable and a categorical variable, respectively. Subgroup analysis was used to investigate the relationship between Hcy and AKI in subgroups. The nonlinear relation between Hcy and AKI was explored by restricted cubic spline regression. Results One hundred and fifty patients (12.48%) developed AKI in all subjects. Multivariate Logistic regression showed that after adjustment for potential confounders, the risk of AKI increased by 1.035 times〔OR=1.035, 95%CI (1.019, 1.052), P

Objective To observe the effect of breathing training on plasma catecholamine concentration，sleep and mood in stroke patients，and unravel the underlying mechanism. Methods Fifty stroke patients were selected and randomly assigned into the control group （n = 25） and training group （n = 25）. Patients in both groups received conventional rehabilitation. In the training group，breathing training was supplemented. The total training time was 6 weeks in two groups. The changes of plasma catecholamine concentration （norepinephrine （NE），epinephrine （E），dopamine （DA））between two groups were compared before and after corresponding interventions. The quality of sleep was assessed by the Pittsburgh Sleep Quality Index scale （PSQI）. The anxiety and depression were assessed by the Self-Assessment Scale for Anxiety （SAS） and the Self-Assessment Scale for Depression （SDS）. Results After 6 weeks of treatment，NE，E and DA concentrations and PSQI，SAS and SDS scores were significantly lower than those before treatment in two groups （all P < 0.05）. These parameters in the training group were significantly lower compared with those in the control group （all P < 0.05）. Conclusions Breathing training improves the quality of sleep and mitigates anxiety and depression in stroke patients，probably via the mechanism of regulating autonomic function and lowering sympathetic activity，thereby reducing catecholamine concentration.

Aiming at the problem that the ability of infrared dim small target detection algorithm based on traditional infrared patchimage (IPI) model to suppress background clutter is not strong, a new detection model (γ-TSIPI) based on γ-norm, total variational regularization, and sparse constraint modeling is proposed. Firstly, the original infrared image is transformed into an IPI, and then the γ-norm and total variational regularization are used to constrain the background patch image to reduce the residual noise in the target image. At the same time, the edge information of the image is retained to avoid excessive smoothness of the restored background image. In addition, considering that the L1 norm in the traditional IPI model may reduce the dim small target excessively, the weighted L1 norm is introduced to improve the recovery ability of γ-TSIPI model. Finally, the Lagrange multiplier method is applied to solve the γ-TSIPI model. Experimental results show that the proposed method can suppress background clutter better, reduce false alarm rate and effectively improve detection performance.

The prevention and treatment of cardiovascular diseases have always been a focus of attention in related fields. This paper discusses the application and mechanism of exogenous and endogenous supplementation with β-hydroxybutyrate in the prevention and treatment of cardiovascular diseases such as myocardial ischemia, myocardial infarction, diabetic cardiomyopathy, hypertension, myocardial inflammation, hypertrophic cardiomyopathy and heart failure. Exogenous β-hydroxybutyrate supplementation can quickly and directly provide substitute energy for the heart and thus prevent and treat heart injury. The comprehensive effect of exogenous β-hydroxybutyrate supplementation is significantly better than that of endogenous β-hydroxybutyrate. Endogenous fatty acid, obtained through a ketogenic diet, needs to be oxidized to β-hydroxybutyrate in vivo for energy supply, which is greatly influenced by glucose and lipid metabolism under the conditions of the basic disease itself. At present, ketogenic diet is not recommended for use in the prevention and treatment of myocardial ischemia or myocardial infarction, and in the treatment of diabetic cardiomyopathy or hypertension. [ABSTRACT FROM AUTHOR]

Objective To investigate the correlation of metabolic syndrome (MS) and its components with arterial stiffness, and to analyze the gender difference. Methods Questionnaires, physical examinations and blood biochemical tests were conducted among 6 737 rural residents in Beijing. The diagnosis of MS is identified based on the 2017 modified standard of Diabetes Society of Chinese Medical Association, and arterial stiffness is defined as brachia-ankle pulse wave velocity (BAPWV) ≥1 700 cm/s. Multivariate Logistic regression analysis was used to analyze the correlation of MS and its components with arterial stiffness. Results In the subjects, arterial stiffness and MS patients accounted for 41.7% and 64.4%, respectively. The MS patients was at a risk of arterial stiffness by 2.36-fold (95%CI: 2.06~2.71) higher than that in the non-MS subjects. Except for the reduced high density lipoprotein-cholesterol (HDL-C), the other MS components were all significantly correlated with arterial stiffness, including elevated blood pressure, blood glucose and triglyceride, and central obesity. The correlation between MS and arterial stiffness was stronger in the women than the men. Conclusion MS is correlated with an increased risk of arterial stiffness, with elevated blood pressure being the most significant component. The effect of MS and its components on arterial stiffness is stronger in female population.

Objective To investigate the epidemiological status and characteristics of common comorbidities among patients with type 2 diabetes mellitus (T2DM) in Beijing. Methods A total of 1 156 965 patients diagnosed with T2DM in 2017 in Beijing were recruited, and their outpatient and inpatient records at all levels of hospitals from 2016 to 2017 were collated and analyzed. The prevalence of 9 comorbidities in this population was described, including hypertension, ischemic heart disease, stroke, lung cancer, chronic kidney disease, severe hearing loss, depression, retinopathy and obstructive pulmonary disease. The differences among different genders and age groups were subsequently compared. Results The enrolled patients were at a mean age of 61.28±13.14 years, and the males accounted for 51.93%. Of them, 29.02% had at least 1 comorbidity. The prevalence of comorbidities was increased with age, and the females had a higher prevalence of comorbidities than the males (P < 0.01). The 4 major comorbidities with the highest prevalence were hypertension (20.16%), depression (6.15%), ischemic heart disease (3.52%) and stroke (3.27%) in order. The females were more likely to suffer from hypertension and depression (P < 0.01), while the males from ischemic heart disease, stroke, obstructive lung disease, lung cancer and chronic kidney disease (P < 0.01). The percentage of patients with 2 or more kinds of comorbidities accounted for 4.59%. The most commonly combined 2 diseases were hypertension with depression (1.75%), hypertension with stroke (1.25%), and hypertension with ischemic heart disease (1.16%). The most common comorbidities were hypertension and stroke in the males (1.51%), and hypertension and depression in the females (2.12%). Conclusion T2DM patients are prone to cardiovascular and metabolic diseases as well as depression. The females are more likely to be accompanied with hypertension and depression, while the males with diseases of other systems and organs, and have relatively poor prognosis.

Millet bran is rich in nutrients and bioactive components. Polyphenols play an important role as one of the active components, but their properties are not very stable and are prone to oxidative degradation under certain conditions. In this paper, we extracted polyphenols from millet bran by ultrasonic combined with DESs and prepared micro-capsules by embedding them to study their physicochemical properties. The results showed that the total polyphenol content of millet bran was 10.58 mg/g under the conditions of ultrasonic-assisted extraction for 30 min at 45 °C with a material-liquid ratio of 1:36 g/mL. After the microcapsules were prepared, the structure of millet bran polyphenol microcap-sules was analyzed by scanning electron microscopy, and it was found that the outer surface of the microcapsules was smooth and the particles were of uniform size. The infrared spectrum showed that the yeast cells had a good effect on the encapsulation of millet bran polyphenols; in the simulated gastric juice, the release of millet bran polyphenol microcapsules was faster than in the simulated intestinal juice, and the core material was released up to 96% within 2h, and the core material was basically released completely after 5 h. Microencapsulation increased the stability performance of millet bran polyphenols, and provided the theoretical basis for the deep development and utilization of millet bran. [ABSTRACT FROM AUTHOR]

To solve the problems of difficult dynamic model updating, insufficient training data and high computing cost in traditional device identification methods, an online Internet of Things (IoT) device identification method based on self-organizing incremental neural network (SOINN) is proposed. First, the device brand features based on document object model (DOM) tree of interactive pages are designed, which have the advantages of easy extraction, small dimensions and wide coverage of devices. The incremental supervised learning method SOINN-SVM is constructed by combining SOINN and support vector machine (SVM) to realize incremental learning of the device brand classifier, which avoids repeatedly using complete data sets to train classification models and speeds up the model updating. Then term frequency-inverse document frequency (TF-IDF) technique is used to optimize the regular matching results, which gives the model field a high weight value. The matching degree between the device to be identified and the model feature library is calculated by combining Jaro distance and weight value to realize the device model recognition. Experimental results show that the accuary of the method is 95. 9%, and 37. 05% more devices can be identified than other methods. The proposed method can dynamically update classification models and reduce the costs of computation and storage. [ABSTRACT FROM AUTHOR]

As an important technology and strategy for revenue and profitability optimization, revenue management (RM) has caught wide attention in the international hotel industry, especially in developed countries, such as the United States, Canada, United Kingdom, France, Germany, and Australia. It has been an important subject for research in the world since it was introduced to the American hotel industry by Marriott about 30 years ago. However, it has been only a few years since Chinese domestic hoteliers began to pay attention to RM. Even now, only a small percentage of hotels in China have applied RM strategies and tactics in their daily pricing and distribution practices. Most of Chinese hotels owned or/and operated by domestic hotel companies without carrying an international brand name have just started to hear about the word of RM when they compete with other hotels run by international hotel chains, most of which have implemented RM. Therefore, the understanding and application of RM in Chinese hotel industry is still in its infancy. This paper is the first empirical study to learn what the factors are that affect hotel RM decision-making and its performance in the unique context of China. Our study is based on in-depth interviews with hotel industry leaders in China and an online survey of 174 valid questionnaires answered by the hoteliers from different high star-rated hotels throughout the country. We used quantitative approaches to analyze the data we have collected. We also compared our findings with those of international researchers. We found that: (1) Who owns or/and runs the hotel affects significantly the hotel's RM decision-making and performance. For example, if a Chinese hotel owner hires an international hotel management contractor to operate its hotel(s), it tends to accept RM and support the management contractor to practice it. If an international hotel chain owns or/and runs a hotel in China, it is highly possible that it will use RM approaches in daily operation to yield the hotel's products and services as it does in other hotels in other countries. (2) The size or the number of guest rooms of a hotel greatly affects its RM decision-making; but it is not related to the hotel's RM performance. On the other hand, a hotel's star rating has strong impact on its RM performance; but it does not affect RM decision-making. (3) Unlike what some international researchers have found, the location, average room rate, occupancy rate and market segmentation of a hotel do not affect its RM decision-making and its RM performance. In conclusion, we suggest that given the current situation in China, the understanding of RM among Chinese hotel owners and managers' and their attitude towards RM play the most important role in RM decision-making and performance. If they understand RM and believe it is helpful, managers will welcome it and invest time and other resources on it. If it is the case, RM decision making will be much easier and effective and it will lead to better RM performance. To make that happen, Chinese hotels, hotel associations, hotel schools, tourism and hotel government authorities need to work together to invest in and improve RM training and education. We believe our study will enrich the findings in RM research and it will be beneficial to the Chinese hotel industry. [ABSTRACT FROM AUTHOR]

Objective To investigate the relationship between long chain non-coding RNA Fez family zinc finger protein 1 antisense ribonucleic acid 1 (FEZF1-AS1) and invasion, migration and Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signal pathway in esophageal squamous cell carcinoma (ESCC) cells. Methods The expression' of FEZF1-AS1 in ESCC cancer tissue and ESCC cell line was detected by real-time quantitative PCR. After knocking down the FEZF1-AS1 of KYSE150 and KYSE510 cells by the constructed lentiviral expression vector, the changes of cell cycle were detected by flow cytometry, the ability of cell proliferation by colony formation assay, the ability of cell invasion by Transwell TM invasion assay, the ability of cell migration by Transwell TM migration and scratch assay, and the protein levels of JAK2 and phosphorylated STAT3 (p-STAT3) by Western blotting. Results FEZF1-AS1 was highly expressed in ESCC cancer tissues, and FEZF1-AS1 expression in KYSE150 and KYSE510 cells were higher than that in normal esophageal squamous epithelial cells. After the knockdown of FEZF1-AS1 expression, the cell cycle and proliferation of ESCC cancer cells had no obvious change, but cell invasion and migration were significantly inhibited, and the level of JAK2 protein decreased and p-STAT3 protein increased. Conclusion The knockdown of FEZF1-AS1 blocks JAK2/STAT3 pathway and inhibits the invasion and migration of ESCC cells.

Pectate lyase is widely applied in ramie degumming and fabric bioscouring in the textile industry. Compared to conventional processes that involve high alkaline and high temperature treatment, enzyme based treatments have significant advantages in fibers protectiveness, improved efficiency of refining, reduced energy consumption and pollution. Hence, it would be highly desirable to construct high-yield alkaline pectate lyase engineered strains and reduce the pectate lyase production cost. In the previous study, pectate lyase gene pel from Bacillus subtilis168 was expressed in Pichia pastoris GS115 after codon usage optimization based on the vector pHBM905A. To improve the expression level, the vector pHBM905BDM with optimized promoter and signal peptide was used to express the optimized gene pels in GS115. The transformant had increased activity from 68 U/mL to 100 U/mL with the improvement in the transcription level by 27% measured by qPCR. The transformants were further screened on pectin plates, where higher halo forming strains were picked for shake-flask fermentation and strain GS115-pHBM905BDM-pels4 showed the highest activity of 536 U/mL. Then plasmid pPIC9K-pels was constructed and electroporated into the GS115-pHBM905BDM-pels4 cells. Subsequently, high-copy transformant was screened by using the medium containing antibiotics G418, strain GS115-pHBM905BDMpPIC9K- pels1 was identified with increased activity of 770 U/mL and the copy number of pels was 7 confirmed by qPCR. Finally, the activity of pectate lyase produced by GS115-pHBM905BDM-pPIC9K-pels1reached to 2 271 U/mL in a 5-L fermentor. The activity of pectate lyase in our study reached the highest level of expression in P. pastoris, showing good application potential in the textile industry.

In eukaryotic cells, DNA is packaged inside the nucleus together with histones to form nucleosomes. Each histone molecule contains two of each core histone subunits H2A, H2B, H3 and H4. Among core histones, the H2A family is of great interest due to the high diversity of specialized variants. These variants have shown important role in critical cellular processes. Epigenetic mechanism in oomycetes is barely known. Phytophthora infestans is a severe pathogen and a model species in oomycetes. In this study, we studied the sequence and expression pattern of H2A variants of P. infestans through genome search, sequences alignment, phylogenetic analysis and realtime qPCR detection. P. infestans contains conserved genes encoding histone variants H2A.X.1, H2A.X.2 and H2A.Z, and these genes have specific expression patterns during development and infection stages. Our datasets provide useful inputs to help explore the epigenetic mechanisms of oomycetes.

Objective: To compare the application valuable of flexible spatial scan statistics and kulldorff scanning window in the cluster detection and early warning of hepatitis A., Methods: The case numbers and incidence data of hepatitis A in 2012 for all the counties (cities, districts)in Yunnan province were collected from China Information System for Disease Control and Prevention and the total number was 1 335. By extracting the time length by month, the flexible spatial scan statistics was tested by retrospective analyses of hepatitis A data in Yunnan in 2012 and compared the results with the Kulldorff circular scan statistic analyses., Results: The results of flexible scanning window showed that there were fifteen hepatitis A spatial clusters in Yunnan province in 2012 and in July, these areas including Gejiu county, Mengzi county and Wenshan county had the strongest clusters (the log likelihood ratio (LLR) = 52.66, P = 0.001). The results of Kulldorff scanning window showed that there were twenty hepatitis A spatial clusters and these areas including Gejiu county, Hekou county, Maguan county, Mengzi county, Pingbian county, Wenshan county had the strongest clusters (LLR = 47.82, P = 0.001). The results of the flexible scanning window were the same as the actual monitoring results. But the results of Kulldorff scanning window showed that in May and June some areas without incidence had the clusters., Conclusion: Flexible scanning window can detect the monthly clusters of the Hepatitis A. Flexible scanning window had a higher accuracy than Kulldorff irregular circular scanning window. Flexible spatial scan statistics had the value in the use of spatial aggregation detecting on hepatitis A.

Objective: To investigate the protective effect of heat shock factor1 (HSF1) and heat shock protein70 (HSP70) on ultraviolet A (UVA)-induced HaCaT cells apoptosis and its mechanism., Methods: The apoptotic HaCaT cell model was induced by UVA irradiation (8mJ/cm2). The cells were randomly divided into three groups, including a control group, a model group (8mJ/cm2 UVA) and a HSP70 transcription inhibitor group (50 micromol/L quercetin). The morphologic alteration of apoptotic cells was investigated by using Hoechst 33258 fluorescent staining. Western blotting was used to investigate protein expression levels of phosphorylated HSF1 and HSP70 at different time points, as well as c-Jun N-terminal kinase (JNK) and phosphorylated JNK were investigated after incubating for 6 hours following UVA irradiation. HSP70 mRNA was detected by Real-Time PCR., Results: Protein expression levels of both phosphorylated HSF1 and HSP70 were time-dependent, appearing an increase at first and then decreased. The increase of p-HSF1 begining at 1h, up to the peak at 3h; and the increase of HSP70 to the peak at 6h and then recovered to the original level at 24h. The pretreatment of HSP70 transcription inhibitor quercetin could significantly inhibit the expression of HSP70 mRNA., and increase the expression of phosphorylated JNK, while increase the apoptosis rate in comparison with UVA model group observed by using Hoechst 33258 fluorescent staining., Conclusion: 8mJ/cm2 UVA irradiation could stimulate the activation of HSF1 and increase HSP70 protein expression. HSF1/HSP70 pathway has a protective effect on UVA-induced HaCaT cells apoptosis and its mechanism is that a large number of HSP70 expression inhibited the activation of JNK.