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In this paper, the discretization error and the convergency are studied for the typical hypersonic flow over hollow cylinder flare(T2-97) using a several successive girds, and a verification procedures based on the Richardson Extrapolation are carried out for this problem. Then with the uncertainty analysis method and the experiment data, the validation procedures are also carried out. The study indicates that the typical problem's Verification and Validation work is achieved based on the existing experiment data and computational capability. [ABSTRACT FROM AUTHOR]

Rhizosphere is a vital area for substance exchange and energy transfer between roots and soil microorganisms. Therefore, diazotrophs in the rhizosphere play a pivotal role in facilitating plant nitrogen acquisition. We investigated the variability in the abundance and community structure of soil diazotrophs and the influencing factors across rhizosphere soils of Cunninghamia lanceolata in three locations: Baisha State-owned Forest Farm in Longyan City (BS), Sanming Forest Ecosystem and Global Change Research Station (SM), and Wuyishan National Forest Park in Nanping City (WYS), located in the western region of Fujian Province, quantified the diazotrophic abundance by using real-time quantitative PCR, and assessed the community structure by high-throughput sequencing. The results showed that soil pH, C:N ratio, and C:(N:P) stoichiometry in SM were notably lower compared to those in BS and WYS. In SM, the abundance of the nifH gene was 6.38×10 8 copies·g -1 , significantly lower than 1.35×10 9 copies·g -1 in BS and 1.10×10 9 copies·g -1 in WYS. Additionally, α diversity index of diazotrophs was lower in SM compared to BS and WYS, while the community structure of diazotrophs in rhizosphere soils of BS and WYS was similar, which differed significantly from that in SM. The diazotrophic sequences in the three forest farms could be divided into 5 phylum, 8 classes, 15 orders, 23 families and 33 genera, with Proteobacteria, α-proteobacteria, and Bradyrhizobium as the dominant phylotypes. Soil pH, available phosphorus, NO 3 - -N and C:(N:P) ratio were identified as significant factors influencing both the abundance and community structure of nifH genes, with soil pH performing the greatest. Taken together, there were spatial variations in the distribution of diazotrophic abundance and community structure in C. lanceolata rhizosphere soils, with soil pH as the primary driving factor.

A high performance liquid chromatography( HPLC) method was established for the fast,and precise determination of ten nucleosides in Fritillariae Cirrhosae Bulbus and its counterfeits. Then multivariate statistical analyses,such as clustering analysis,principal component analysis( PCA),and Fisher' s linear discriminant analysis( LDA),were conducted to establish a discriminant function model for an integrated analysis. The results indicated that data acquisition time of a single sample was shortened within 16 min by the HPLC method. In the range of 5-1 000 mg·kg~(-1),the mass concentrations of all nucleosides exhibited good linear relationships with the corresponding peak areas( R2> 0. 999). The spiked recoveries were in the range of 93. 83%-108. 9% with RSDs of0. 12%-1. 3%( n = 5). The limit of quantitation( LOQ) was 0. 98-4. 13 mg·kg~(-1). As revealed by the clustering analysis,Fritillariae Cirrhosae Bulbus and the counterfeits could be discriminated into two clusters based on the content of nucleosides. Fisher's LDA could achieve this discrimination,while PCA dimension reduction failed. The accuracy of the discriminant function model established on the screened characteristic indicators reached 97. 5%. The present study proposed a new identification method of Fritillariae Cirrhosae Bulbus with one-dimensional indicators,which is simple,accurate,and reliable. It can provide a scientific basis for further optimizing the identification techniques for Fritillariae Cirrhosae Bulbus and inspiration for quality control strategy development of Chinese medicinal materials.

Objective: To observe the clinical effect and safety of the Chinese patent medicine Ningmitai Capsules (NMT) in relieving lower urinary tract symptoms (LUTS) in the patient with benign prostatic hyperplasia (BPH)., Methods: We randomly assigned 40 BPH patients to an experimental and a control group of equal number to receive oral administration of NMT at 4 capsules tid and terazosin hydrochloride tablets at 2 mg qd, respectively, both for 14 days. At 7 and 14 days after medication, we recorded and compared the International Prostate Symptoms Score (IPSS), maximum urinary flow rate (Qmax), quality of life (QoL) scores, results of urinalysis and blood routine examination, and indexes of hepatic and renal function., Results: Both NMT and terazosin significantly improved the total IPSS score, the IPSS scores in the storage and voiding phases, increased Qmax and urine output, reduced post-void residual urine (PVR), and improved the QoL of the patients. The patients of the NMT group showed a better relief of incomplete bladder emptying, more improved QoL and fewer adverse reactions, while those treated with terazosin achieved a better attenuation of weak urine stream and PVR., Conclusions: NMT is safe and effective in relieving LUTS in BPH patients. Each of NMT and terazosin has its own advantages in attenuating urinary tract irritation and obstruction, but whether their combination may produce a better effect on LUTS and the specific mechanisms of NMT improving acute symptoms of BPH are yet to be further studied.

Objective: To explore the effects of sildenafil on bladder compliance and endothelin-1 in the rabbit model of partial bladder outlet obstruction., Methods: A total of 24 adult male New Zealand white rabbits were randomly divided into group A, group B, group C and group D (n = 6 each). The rabbit model of partial bladder outlet obstruction was established in groups C and D while groups A and B underwent a sham operation. Daily sildenafil (10 mg/kg) was dosed to groups B and C by lavage. Daily normal saline was dosed similarly to groups A and D. Bladder urodynamic examinations were conducted in each group at Week 16. Then bladder was isolated and weighed from each group. And ET-1 in bladder tissue was measured by ELISA., Results: Pressure thresholds for voiding (PT) in A-D groups were (10.6 ± 2.0), (11.6 ± 2.7), (14.0 ± 4.2) and (20.4 ± 6.1) cm H2O respectively. Compared with groups A, B and C, PT in group D was significantly higher (all P < 0.01). Bladder compliance in 4 groups were (2.75 ± 0.51), (2.78 ± 0.46), (4.98 ± 2.15) and (1.22 ± 0.25) ml/cm H2O respectively. Compared with groups A, B and C, bladder compliance was significantly lower in group D (all P < 0.01). Bladder compliance in group C was higher than that in groups A and B (both P < 0.01). The weights of bladder specimens in 4 groups were (5.0 ± 0.4), (4.6 ± 0.4), (8.2 ± 1.3) and (17.9 ± 2.3) g respectively. Compared with groups A and B, the weights of groups C and D were significantly heavier (all P < 0.01). And the weight of group D was much greater than that of group C (P < 0.01). The contents of ET-1 in bladder tissue of 4 groups were (72 ± 19), (69 ± 18), (76 ± 21) and (106 ± 29) pg/g respectively. Compared with groups A, B and C, ET-1 in bladder tissue was significantly higher in group D (all P < 0.05)., Conclusions: Daily sildenafil can effectively alleviate the damage of rabbit bladder compliance from partial bladder outlet obstruction and protect bladder functions. Its mechanism may be related with the down-regulation of ET-1 in bladder tissue of partial bladder outlet obstruction.

The fatty acid concentrations in maize grain were analyzed with a set of 294 samples including normal inbred lines, high-oil inbred lines and high-oil recombinant inbred lines (RIL). The method of partial least squares (PLS) regression with internal cross validation was employed to develop the measuring models of near-infrared reflectance spectroscopy (NIRS) for concentrations of four major fatty acids, palmitic, stearic, oleic and linoleic acids, as well as oil concentration in maize grain. The NIRS models were accurate for oleic acid, linoleic acid and oil concentrations. The determination coefficients of these models in cross validation were 0.89, 0.88 and 0.91, respectively; the determination coefficients in external validation were 0.86, 0.84 and 0.92, respectively; and the ratio of standard deviation (SD) to root mean square error of validation (RMSEV) in both calibration and external validation sets (RSC(P)) was higher than 2.5. But the models for palmitic and stearic acid concentrations were not accurate enough with determination coefficients in cross validation and external validation lower than 0.80, and RSC(P) lower than 2.5. Further practical validation showed that the predicted results by using NIRS models for oleic acid, linoleic acid and oil concentrations were accurate and reliable, which will be a useful approach to the measurement of a large number of breeding samples during genetic improvement of oil quality and quantity in maize.

Simple sequence repeat (SSR) molecular marker was used to measure the genetic diversity of D-genome in 26 synthesized hexaploid wheat (AABBDD) introduced from CIMMYT. Twenty-three D-genome specific SSR primers were selected for PCR amplification, among which 22 primers can detect polymorphism. A total of 92 alleles were identified at 23 loci using the above SSR primers, with an average of 4 alleles per locus. The 92 alleles were used to calculate Nei's similarity index (GS) and the genetic distance (GD). It was also found that the mean genetic distance between 26 synthesized hexaploid wheat was 0.4955, which was obviously high. From the above results, it can be indicated that the genetic variation of D-genome in synthesized hexaploid wheat was abundant and could be used to improve the genetic diversity in wheat breeding. Interestingly, synthesized hexaploid wheat 17 and 18 shared the same D-genome donor, but three of 23 detected SSR loci were polymorphic between the two materials. Therefore, during the period of allopolyploidization, there was genetic differentiation in repeat region of donor genome.