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Open access

Qing Zhou, Xu-wen Xu, De-ming Tan, Yu-tao Xie, Yun-zhu Long and Meng-hou Lu

Abstract

Objective A diagnostic model was established to discriminate infectious diseases from non-infectious diseases.

Methods The clinical data of patients with fever of unknown origin (FUO) hospitalized in Xiangya Hospital Central South University, from January, 2006 to April, 2011 were retrospectively analyzed. Patients enrolled were divided into two groups. The first group was used to develop a diagnostic model: independent variables were recorded and considered in a logistic regression analysis to identify infectious and non-infectious diseases (αin = 0.05, αout = 0.10). The second group was used to evaluate the diagnostic model and make ROC analysis.

Results The diagnostic rate of 143 patients in the first group was 87.4%, the diagnosis included infectious disease (52.4%), connective tissue diseases (16.8%), neoplastic disease (16.1%) and miscellaneous (2.1%). The diagnostic rate of 168 patients in the second group was 88.4%, and the diagnosis was similar to the first group. Logistic regression analysis showed that decreased white blood cell count (WBC < 4.0×109/L), higher lactate dehydrogenase level (LDH > 320 U/L) and lymphadenectasis were independent risk factors associated with non-infectious diseases. The odds ratios were 14.74, 5.84 and 5.11 (P ≤ 0.01) , respectively. In ROC analysis, the sensitivity and specificity of the positive predictive values was 62.1% and 89.1%, respectively, while that of negative predicting values were 75% and 81.7%, respectively (AUC = 0.76, P = 0.00).

Conclusions The combination of WBC < 4.0×109/L, LDH > 320 U/L and lymphadenectasis may be useful in discriminating infectious diseases from non-infectious diseases in patients hospitalized as FUO.

Open access

Wen Sun, Lin Han, Wenmao Xu and Yazhen Sun

Abstract

Objective: The objective of this work is to search for a novel method to explore the disrupted pathways associated with periodontitis (PD) based on the network level.

Methods: Firstly, the differential expression genes (DEGs) between PD patients and cognitively normal subjects were inferred based on LIMMA package. Then, the protein-protein interactions (PPI) in each pathway were explored by Empirical Bayesian (EB) co-expression program. Specifically, we determined the 100th weight value as the threshold value of the disrupted pathways of PPI by constructing the randomly model and confirmed the weight value of each pathway. Meanwhile, we dissected the disrupted pathways under the weight value > the threshold value. Pathways enrichment analyses of DEGs were carried out based on Expression Analysis Systematic Explored (EASE) test. Finally, the better method was selected based on the more rich and significant obtained pathways by comparing the two methods.

Results: After the calculation of LIMMA package, we estimated 524 DEGs in all. Then we determined 0.115222 as the threshold value of the disrupted pathways of PPI. When the weight value>0.115222, there were 258 disrupted pathways of PPI enriched in. Additionally, we observed those 524 DEGs that were enriched in 4 pathways under EASE=0.1.

Conclusion: We proposed a novel network method inferring the disrupted pathway for PD. The disrupted pathways might be underlying biomarkers for treatment associated with PD.

Open access

Chi Xu, Wen-Zhi Zeng, Jing-Wei Wu and Jie-Sheng Huang

Abstract

Intermittent irrigation has attracted much attention as a water-saving technology in arid and semi-arid regions. For understanding the effect of intermittent irrigation on water and solute storage varied from irrigation amount per time (IRA), irrigation application frequency (IRAF), irrigation intervals (IRI) and even soil texture (ST), intermittent irrigation experiment was carried out in 33 micro-plots in Inner Mongolia, China. The experiment results were used for the calibration and validation of HYDRUS-1D software. Then 3 ST (silty clay loam, silty loam, and silty clay), 5 IRA (2, 4, 6, 8, and 10 cm), 4 IRAF (2, 3, 4, and 5 times) and 4 IRI (1, 2, 3, and 4 days) were combined and total 240 scenarios were simulated by HYDRUS-1D. Analysis of variance (ANVOA) of simulated results indicated that ST, IRA, and IRAF had significant effect on salt and nitrate nitrogen (NO3 -N) storage of 0-40 cm depth soil in intermittent irrigation while only ST affected soil water storage obviously. Furthermore, salt leaching percentage (SLP) and water use efficiency (WUE) of 0-40 cm depth were calculated and statistical prediction models for SLP were established based on the ANOVA using multiple regression analysis in each soil texture. Then constraint conditions of soil water storage (around field capacity), salt storage (smaller than 168 mg·cm−2), WUE (as large as possible) in 0-40 cm depth and total irrigation water amount (less than 25 cm) were proposed to find out the optimal intermittent irrigation strategies. Before sowing, the optimal irrigation strategy for silty clay loam soil was 6 cm IRA, 3 times IRAF, and 2 days IRI respectively. For silty loam and silty clay soils, IRA, IRAF, and IRI were 8 cm, 3 times, and 2 days respectively.

Open access

Wen He, Guanhua Xu, Zuochao Rong, Gen Li and Min Liu

Abstract

Considering the low efficiency during the process of traditional calibration for digital-display vibrometers, an automatic calibration system for vibrometers based on machine vision is developed. First, an automatic vibration control system is established on the basis of a personal computer, and the output of a vibration exciter on which a digital-display vibrometer to be calibrated is installed, is automatically adjusted to vibrate at a preset vibration level and a preset frequency. Then the display of the vibrometer is captured by a digital camera and identified by means of image recognition. According to the vibration level of the exciter measured by a laser interferometer and the recognized display of the vibrometer, the properties of the vibrometer are calculated and output by the computer. Image recognition algorithms for the display of the vibrometer with a high recognition rate are presented, and the recognition for vibrating digits and alternating digits is especially analyzed in detail. Experimental results on the built-up system show that the prposed image recognition methods are very effective and the system could liberate operators from boring and intense calibration work for digital-display vibrometers

Open access

Wen-Zhi Zeng, Chi Xu, Jing-Wei Wu, Jie-Sheng Huang and Tao Ma

Abstract

A facility of BaPS (Barometric Process Separation) and indoor incubation experiments were used to determine the effect of soil salinity on soil respiration and nitrogen transformation. The rates of soil respiration, gross nitrification, denitrification, ammonium and nitrate nitrogen concentrations and relevant soil parameters were measured. Results showed that soil respiration and nitrification and denitrification rates were all affected by soil salinity. Furthermore, the effect of soil salinity level on nitrification and denitrification rates had a threshold value (EC1:5 = 1.13 dS/m). When soil salinity level was smaller to this threshold value, the rates of nitrification and denitrification increased with soil salinity while they were reduced when soil salinity level was larger than the threshold value. Moreover, the changing law of soil respiration rate with soil salinity was similar with the nitrification and denitrification rates while the variation tendency was opposite. In addition, the transformation form urea to ammonium and nitrate nitrogen was also reduced with the increase of soil salinity and the reduced effect could be expressed by exponential functions.

Open access

Y. Wen, K. Uchiyama, G. Xu, S. Ueno, W. Han, W. Xie and Y. Tsumura

Abstract

Being an economical and endangered species, microsatellite markers of Taxus chinensis var. mairei were very limited. We have developed a set of microsatellite markers, which was benefit for future genetic analysis of this rare species. Polymorphic loci were developed from congeneric species by cross-species amplification methods, and new primers were redesigned to test for potential null alleles. 15 loci showed polymorphism. The number of alleles per locus varied from 2 to 23 tested in 48 individuals. The observed heterozygosity (Ho) and expected heterozygosity (He) values ranged form 0.000 to 0.854 and 0.082 to 0.827, respectively. Newly redesigned primer confirmed that no null allele existed in most suspected loci. These microsatellite markers will be useful for future genetic analysis and conservation of this endangered species.

Open access

Xiaoli Yao, Wen Wei, Juanjuan Li, Lijun Wang, ZhiLiang Xu, Yingwen Wan, Kaiyang Li and Shengrong Sun

Abstract

Background: Many breast-imaging techniques have been developed as primary clinical methods for identifying early-stage breast cancers and differentiating them from benign breast tumors. For the large population of China, any screening method that is rapid, economical, and accurate is worthy of evaluation.

Objective: To compare the effectiveness of mammography, color Doppler ultrasonography, and far-infrared thermography in the screening and early diagnosis of breast cancer.

Methods: Data from 2036 women with breast disease between January 2007 and May 2011 were included in this study. All patients underwent mammography, ultrasonography, and far-infrared thermography imaging. The diagnostic accuracy of the three methods was determined using postoperative pathological results as the diagnostic criterion standard.

Results: There were 480 patients found to have breast malignancies on pathological examination. The lesion diameter was <2 cm in 853 cases. Among them, breast cancer was found in 73 patients and carcinoma in situ in 22 patients. There was no difference in the accuracy of mammography and ultrasonography (96.1% versus 95.8%). However, there were significant differences between the accuracy of far-infrared thermography (97.1%) and ultrasonography and mammography. The sensitivity and specificity of far-infrared thermography was superior to that of mammography and ultrasonography in lesions <2 cm in diameter.

Conclusion: Far-infrared thermography is more accurate for breast cancer screening than ultrasonography and mammography for lesions <2 cm. It has comparable diagnostic accuracy to ultrasound and better diagnostic accuracy than mammography for lesions >2 cm in diameter.

Open access

Wen-Zhi Zeng, Jie-Sheng Huang, Chi Xu, Tao Ma and Jing-Wei Wu

Abstract

For improving the understanding of interactions between hyperspectral reflectance and soil salinity, in situ hyperspectral inversion of soil salt content at a depth of 0-10 cm was conducted in Hetao Irrigation District, Inner Mongolia, China. Six filtering methods were used to preprocess soil reflectance data, and waveband selection combined by VIP (variable importance in projection) and b-coefficients (regression coefficients of model) was also applied to simplify model. Then statistical methods of partial least square regression (PLS) and orthogonal projection to latent structures (OPLS) were processed to establish the inversion models. Our findings indicate that the selected sensitive wavebands for the 6 filtering methods are different, among which the multiplicative signal correction (MSC) and standard normal variate methods (SNV) have some similar sensitive wavebands with unfiltered data. Derivatives (DF1 and DF2) could characterize sensitive wavebands along the scale of VNIR (350-1100 nm), especially the second derivative (DF2). The sensitive wavebands for continuum-removed reflectance method (CR) have protruded many narrow absorption features. For orthogonal signal correction method (OSC), the selected wavebands are centralized in the range of 565-1013 nm. The calibration and evaluation processes have demonstrated the second order derivate filtering method (DF2) combined with waveband selection is superior to other processes, for it has high R 2 (larger than 0.7) both in PLS and OPLS models for calibration and evaluation, by choosing only 156 wavebands from the whole 700 wavebands. Meanwhile, OPLS method was considered to be more suitable for the analyzing than PLS in most of our situations.