Search

This study aimed to investigate the effect of different storage temperatures and methods for fresh tea leaves on the sensory quality, aroma components and biochemical components of broken black tea prepared from‘Yinghong 9’ tea leaves stored at 15, 25, 22–28 (room temperature) or 36–37 ℃ using sensory evaluation and headspace solid phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS). The results showed that storage of fresh tea leaves at 15 ℃ could enhance the fresh and brick taste, sweetness and sweet volatile compound contents of broken black tea, which was more favorable to the formation of the quality of broken black tea. However, storage at 36–37 ℃ of fresh tea leaves could significantly affect the sensory quality and quality components of broken black tea. These results provide a reference for fresh tea leaf management and the quality improvement of black broken tea.

Objective To analyze the detection characteristics of a novel serum marker, hepatitis B core-associated antigen (HBcrAg), in the HBsAg-/HBV DNA+ blood donors in Wuxi. Methods A total of 37 previous HBsAg-/HBV DNA+ blood donors were followed up by telephone and their serum was obtained, and the serum of 22 HBsAg-/HBV DNA+ blood donors was detected by electrochemiluminescence and real-time PCR nucleic acid screening as the OBI group for HBcrAg enzyme-linked immunosorbent assay(ELISA). The serum of 20 healthy blood donors who underwent dual ELISA and one nucleic acid testing(NAT) was selected as the healthy control group, and the serum of 20 patients with chronic hepatitis B who were clinically diagnosed by Wuxi Fifth People's Hospital was selected as the experimental CHB group, and HBcrAg ELISA was detected respectively. The correlation analysis between HBcrAg and HBeAb, HBcAb, ALT and HBV DNA in the OBI group was performed. Results Thirty-seven blood samples were detected by chemiluminescence for HBsAg and NAT, and 22 HBsAg-/HBV DNA+ samples were detected in the OBI group, with a detection rate of 59.46%. The serum HBcrAg expression content (ng/mL) between the OBI group, the healthy control group and the CHB group were (0.92±0.13), (0.47±0.09) and (1.14±0.23), respectively, and the differences were statistically significant (P0.05). Conclusion The expression of HBcrAg in the OBI group and CHB group was higher than that in the healthy control group, and the serum HBcrAg was not correlated with HBeAb, HBcAb, ALT and HBV DNA to a certain extent. HBcrAg has a good application prospect in screening HBsAg-/HBV DNA+ blood donors.

[Objective] Ecological land fragmentation has a serious impact on the structural integrity and function of the ecosystem. The conflict between construction land expansion and ecological land fragmentation is one of the problems that need to be solved in the process of implementing the development and protection strategy for harmonious coexistence between humans and nature. [Methods] In this study, based on the analysis of temporal and spatial changes in ecological land, a comprehensive indicator system of fragmentation degree was established for the southern Jiangsu Province region to explore the temporal and spatial characteristics of ecological land fragmentation degree. Based on the theory of the environmental Kuznets curve (EKC), the response of ecological land fragmentation degree to construction land expansion was investigated. [Results] (1) From 2000 to 2020, the ecological land in southern Jiangsu Province was mainly converted into construction land, followed by cultivated land. A certain amount of cultivated land and a small amount of construction land were converted into ecological land; (2) The degree of ecological land fragmentation increased first and then decreased. Along the Yangtze River and in the surrounding areas of key water bodies such as the Taihu Lake, the Gucheng Lake, and the Gehu Lake, there was a remarkable increase in the degree of fragmentation; (3) There is an inverted U-shaped relationship between the scale of construction land and the fragmentation of ecological land. With the increase of the area of construction land, the degree of fragmentation of ecological land increases first and then decreases. [Conclusion] The spatiotemporal response of ecological land fragmentation to construction land expansion is consistent with the EKC theory, and most urban centers in southern Jiangsu Province have reached the inflection point by 2020. By exploring the balance between ecological land occupation and compensation, conducting ecological planning in advance, building ecological barriers, timely assessing the impact of construction land expansion on ecological land, and formulating response measures, the layout coordination of construction land and ecological land will be improved, and the coordinated progress of “smart growth” and green development can be realized.

In order to explore the structural characteristics and immunomodulatory effects of pectic polysaccharides in Jasminum sambac flower waste, two polysaccharides, JSP-3 and JSP-4, were separated by water extraction, alcohol precipitation, deproteinization, anion exchange chromatography and gel chromatography. Its structural characteristics were analyzed with relative weight average molecular weight, monosaccharide composition, partial acid hydrolysis-LC-MS and NMR. Finally, the immunomodulatory effects of two polysaccharides were studied by using murine macrophage RAW 264.7 as a model, and measuring the effects on proliferation, phagocytosis, ROS production and secretion of NO, TNF-α and IL-6. The results showed that JSP-3 and JSP-4 were two homogeneous polysaccharides with relative molecular weights of 15.48 kDa and 44.75 kDa, respectively, mainly composed of galacturonic acid, rhamnose, galactose and arabinose, with different proportions of galacturonan domain (JSP-3: 32.87%±3.53%, JSP-4: 68.64%±0.67%) and rhamnogalacturonan domain (JSP-3: 61.12%±3.37%, JSP-4: 28.28%±0.46%), indicating that both are pectic polysaccharides. Compared with the control group, JSP-3 and JSP-4 have no cytotoxic effect within 12.5~100 μg/mL. At a certain concentration, it increased the production of ROS and the secretion of NO, TNF-α and IL-6, also promoted the phagocytosis of mouse macrophages significantly (P

Background Urinary calculi in primary aldosteronism (PA) have been studied almost only in case reports, and most of which have been reported to be associated with nephrolithiasis. Literature review demonstrates that there are few reports on the prevalence, clinical characteristics and possible causative factors of asymptomatic nephrolithiasis/nephrocalcinosis in PA. Objective To investigate clinical features and possible causative factors of asymptomatic nephrolithiasis/nephrocalcinosis in primary aldosteronism patients in Sichuan. Methods In this retrospective study, we enrolled 147 PA patients from Department of Endocrinology, Sichuan Provincial People's Hospital from January 2017 to April 2021, including 34 also with asymptomatic nephrolithiasis/nephrocalcinosis and 113 patients with PA alone. Clinical data were collected, including sex, age, duration of hypertension, duration of hypokalemia, the lowest serum potassium level in medical history, abnormal glucose metabolism, smoking history, drinking history, systolic blood pressure at admission, diastolic blood pressure at admission, body mass index, waist circumference, estimated glomerular filtration rate (eGFR) , fasting blood glucose, serum uric acid, total protein, albumin, potassium, sodium, calcium, magnesium, phosphorus, carbon dioxide, pH value, bicarbonate (HCO3) , total cholesterol, triglyceride, low-density lipoprotein, high-density lipoprotein, and glycated hemoglobin, plasma aldosterone concentration, direct renin concentration, and aldosterone-renin ratio in upright posture, serum 25 hydroxyvitamin D, and parathyroid hormone (PTH) , 24-hour urinary electrolyte excretion (K, Na, Ca, Mg, P) , urine microalbumin to creatinine ratio, and urinary pH value. Binary Logistic regression analysis was used to explore the independent risk factors of asymptomatic nephrolithiasis/nephrocalcinosis in PA. Results Compared with patients with PA alone, those also with asymptomatic nephrolithiasis/nephrocalcinosis had higher proportion of males, previous or current smokers, and previous or current drinkers, higher mean levels of serum pH value, HCO3 and PTH, longer mean duration of hypertension, as well as lower eGFR (P

为寻找一种能快速识别核桃油品牌和产地的方法，以来自4个品牌3个产地的冷榨一级核桃油为研究对象，分批次收集了300个样品，用荧光检测仪进行样品扫描，分两个时间段采集三维荧光光谱，间隔为1个月。对收集的共600组光谱数据运用主成分分析（PCA）进行特征提取，同品牌或同产地的样品分别选取主成分1组成新的数据集，达到数据降维，再结合偏最小二乘判别（PLS-DA）和人工神经网络判别（BP-ANN）化学模式识别方法，对应构建核桃油的品牌识别模型和产地识别模型。结果表明：PLS-DA和BP-ANN对核桃油的品牌和产地的识别率都能达到100%。因此，三维荧光光谱与PLS-DA和BP-ANN方法结合，可用于快速识别核桃油的品牌和产地。In order to find a method to quickly identify brand and origin of walnut oil, cold pressed first-grade walnut oils of four brands from three origins were used as the research object, 300 samples were collected in batches, samples were scanned with a fluorometric detector and three-dimensional fluorescence spectra were collected in two time intervals of one month. A total of 600 sets of spectral data collected were extracted by PCA, and principal component 1 was selected from samples of the same brand or origin to form a new data set to achieve data dimension reduction. Then, combined with PLS-DA and BP-ANN chemical pattern recognition methods, brand recognition model and origin recognition model of walnut oil were constructed. The results showed that PLS-DA and BP-ANN could both accurately identify the corresponding brand and origin of walnut oil with the recognition rate of 100%. So the combination of three-dimensional fluorescence spectra with PLS-DA and BP-ANN can be used as a method for rapid identification of brand and origin of cold pressed first-grade walnut oil.

Gear is widely applied in mechanical transmission systems. Gear meshing stiffness is a time varying parameter because of the periodical changing of the numbers of teeth involved in meshing process，the meshing vibration is generated during gear meshing. When the cracks are existed in roots of gear teeth，the meshing stiffness decreased，vibration response of the system due to gear meshing changed as well. Thus，identifying gear meshing stiffness through vibration response is a method monitoring healthy state of gear pairs. For the time-varying character of meshing stiffness，a gear meshing stiffness identification algorithm is proposed based on exponential window recursive least square method（EWRLS） interception and instantaneous frequency of the vibration signal. During the identification of meshing stiffness，EWRLS algorithm takes the speed curves of the input and output gears as the identification input signal and observation signal，respectively. In the algorithm，the exponential window is applied to intercept data，and the recursive least square algorithm is applied to estimate parameters of the system. To calculate speed curve of the input and output gears，the empirical mode decomposition （EMD） method is used to decompose vibration signal into intrinsic mode function （IMF） of different frequency，the IMFs are used to reconstruct character signals of input and output gears basing on the mean frequency of IMFs. The Hilbert transform is applied to calculate the instantaneous frequency curve of the character signals to obtain the speed curves of gears. The simulated signal and measured signal are used to validate the algorithm，results show that the EWRLS algorithm can identify time-varying meshing stiffness of gear pair.

In recent years, open-source RISC-V microprocessors represented by Hummingbird E203 have received widespread attention and application in both academia and industry due to their low power consumption and good performance. To improve the performance of microprocessors and reduce pipeline stalls caused by branch instructions, branch prediction technology has become one of the important techniques widely used in modern microprocessors. However, the branch predictor currently used in the Hummingbird E203 is a lightweight static branch predictor, facing the challenge of low branch prediction accuracy. Since using a dynamic branch predictor with higher prediction accuracy can further reduce the overhead caused by mispredictions leading to redirecting fetching, various implementations of dynamic branch predictors have been explored based on the original microarchitecture to improve branch prediction accuracy while considering resource overhead. Experimental results show that among various dynamic branch predictors, the one achieving the best results is the adaptive dynamic branch predictor combining static branch prediction with Branch History Register (BHR). On the Dhrystone benchmark program, its branch prediction accuracy can be increased from the original 84.6% to 94.8%, and the score from 1.296 463 to 1.314 418. On the Coremark benchmark program, its branch prediction accuracy can be increased from the original 67% to 78.7%, and the score from 2.120 000 to 2.138 008. [ABSTRACT FROM AUTHOR]

Objective To find out the suspicious food, pathogenic factors and risk factors of a foodborne disease outbreak in a factory, and to discuss the problems exposed in the investigation of the incident, so as to provide reference for the prevention, control and investigation of similar incidents in the future. Methods A case was defined as the onset of abdominal pain or diarrhea (≥3 times/24 hours) or vomiting in a person who worked in M factory from March 3 to March 4 in 2019. Case interviews and retrospective research was carried out using descriptive and analytical epidemics pathological method. Stool specimens of the cases, leftover food and related environmental samples were gathered for pathogen isolation and toxin gene detection using polymerase chain reaction (PCR). Results 106 cases were identified with a attack rate of 73.6% (106/144). The symptoms were diarrhea (78.3%, 83/106), abdominal cramps (78.3%, 83/106), abdominal gas pains (9.4%, 10/106), and no fever. The epidemic curve showed a point source exposure pattern. The median incubation time was 10 hours (range: 2-22 h). Illness were associated with three food items of the lunch on March 3 in 2019 by univariate analysis and Logistic regression analysis: braised fish pieces [relative risk (RR)=1.55, 95% confidence interval (95%CI): 1.29-1.85], pork stir-fried with garlic sprouts (RR=1.26, 95%CI: 1.01-1.57) and duck blood stir-fried with pickles (RR=1.47, 95%CI: 1.16-1.87). Alpha toxin and enterotoxin CPE genes were positive and beta toxin genes was negative in the Clostridium perfringens strain isolated in anal swabs of three patients, three environmental samples and two leftover food samples. There were possible bacterial contamination and reproduction in the processing and preparation of enterprise D, which delivered food. Conclusion This incident was caused by the food poisoning of Clostridium perfringens caused by the consumption of a meal provided by a catering company. After the meal was delivered, it should be cooled quickly and stored at low temperature. If it cannot be eaten immediately, it should be heated sufficiently before eating.

This paper aims to address the problems of low accuracy and high leakage rate due to the influence of different insulator sizes and background interference in the target detection task of power systems. Firstly, a convolutional block attention module (CBAM) is added to the YOLO v7 backbone network to make the network model pay more attention to the insulator features from both channel and space aspects and reduce the leakage rate in insulator detection. Secondly, a concentrated feature pyramid (CFP) is added to the deeper layer of the network model to allow the information exchange and aggregation of feature maps at different scales, thus obtaining more comprehensive insulator features and improving insulator detection accuracy. Finally, the k-means algorithm is used to cluster the preselected frames to obtain the most suitable insulator preselected frame size. The experimental results show that the improved YOLO v7 network model has a detection mAP (mean average precision) of 96.2%, a precision of 90.8%, and a recall of 93.8%. The improved method in this paper has a wide application prospect in the insulator detection of power systems. [ABSTRACT FROM AUTHOR]

Objective To investigate the correlation between insomnia and sleep quality in adolescents. Methods According to Insomnia Severity Index (ISI) Chinese Version, 3342 students technician training in school were divided into non insomnia group (N = 2345) and insomnia group (N = 997). Sleep and emotional state were assessed by ISI Chinese Version, Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Self?Rating Anxiety Scale (SAS) and Beck Depression Inventory (BDI). The social demographic data were collected simultaneously. Results The number of insomnia, daytime sleepiness, anxiety and depression in the population was 997 (29.83%), 568 (17.00%), 243 (7.27%) and 1287 (38.51%), respectively. The comparison of social demographic data between 2 groups showed that the proportion of female (P = 0.000), poor physical condition (P = 0.000), non?only child (P = 0.006), high learning pressure (P = 0.000) and smoking (P = 0.027) in insomnia group were significantly higher than those in non insomnia group. The total scores of ISI Chinese Version (P = 0.000), ESS (P = 0.000), SAS (P = 0.000) and BDI (P = 0.000) in insomnia group were significantly higher than those in non insomnia group. Pearson correlation analysis showed that ISI Chinese Version and PSQI scores were positively correlated with ESS score (r = 0.361, P = 0.000; r = 0.064, P = 0.000), SAS score (r = 0.326, P = 0.000; r = 0.069, P = 0.000) and BDI score (r = 0.529, P = 0.000; r = 0.067, P = 0.000), and ISI Chinese Version had higher correlation (r = 0.300-0.600) with the above scores than PSQI (r < 0.100). Further partial correlation analysis showed that ISI Chinese Version score was negatively correlated with PSQI score (r = - 0.056, P = 0.001). Conclusions Higher proportion of female, worse physical condition, more non?only child, greater learning pressure and higher smoking rate were observed in insomnia group. Daytime sleepiness, anxiety and depression in insomnia group were more serious than those in non insomnia group, but PSQI score can not distinguish the above differences. Compared with PSQI, ISI Chinese Version is more closely related to daytime sleepiness, anxiety and depression, and might be more suitable for assessing insomnia in adolescents. DOI: 10.3969/j.issn.1672-6731.2017.09.007

High-speed serial interface is a key technology to improve the bandwidth of high-performance interconnection networks, and the channel equalizer is the core component to improve signal integrity. This paper uses the modern digital signal processing (DSP) structure to propose a deep neural network (DNN)-based high-speed channel equalization research method. This method overcomes the inherent shortcoming that the decision speed of the traditional decision feedback equalizer (DFE) is limited by the feedback loop when facing high-speed channels above 50GB in the future. The simulation results show that, compared with the traditional 2-tap DFE architecture with 15-tap FFE, the proposed 3-layer DNN structure has better equalization effect and faster equalization convergence speed, when the PAM4 encoding method is used, the high-speed channel baud rate is 28GB, and the channel loss is 15dB, or the baud rate is 56GB and the channel loss is 30dB. [ABSTRACT FROM AUTHOR]

Reference material is indispensable for the reliability, comparability, and accuracy of transgenic detection results. In this paper, the effects of long-term preservation of matrix reference materials on PCR detection and the stability of low content reference materials were studied. The reproducibility and quantity stability of transgenic reference materials and transgenic samples with different contents were detected by three methods (common qualitative PCR, real-time fluorescent PCR, and droplet digital PCR). The result showed that the transgenic reference material with 0.1% GM content could still be clearly amplified after 9 years of storage, and the Ct value was about 36. The digital PCR revealed that the quantity of GM matrix reference materials remained stable for long storage time. There was no effect on the detection of transgenic elements in sample mixed with soybean, corn and rice powder which stored at -70 to -75 °C for 11 years. In summary, the long-term storage of GM matrix reference materials at low temperature would not affect the detection of each transgenic component and its application as a positive control for transgenic nucleic acid detection. [ABSTRACT FROM AUTHOR]

At present, the port rate of the mainstream high-performance interconnection network reaches 100~400 Gbps, and the single channel rate reaches 25~50 Gbps. For the data transmission at this rate, Forward Error Correction (FEC) coding is a necessary technology to improve the reliability. The Ethernet international standard IEEE 802. 3 uses Forward Error Correction codes RS(528,514) and RS(544,514), but these two code types are difficult to meet the performance requirements of high-performance interconnect networks in terms of low latency. Firstly, this paper analyzes the encoding and decoding structures of RS code and quantitatively studies the relationship between RS code type parameters and encoding and decoding delays. Secondly, a new coding type RS(271,257) for low-latency high-performance interconnection network is proposed, and its advantages and disadvantages in bandwidth consumption and error correction capability are compared. Finally, based on RS(271,257), this paper implements the network coding sub-layer and performs the resource consumption evaluation and delay performance simulation. Considering the factors of resource consumption, error correction ability and delay performance, RS (271, 257) is an ideal low-latency forward error correction coding type, which can meet the design requirements of the current HPC-oriented low-latency high-performance interconnection network coding sub-layer. [ABSTRACT FROM AUTHOR]

Environmental governance has become an important part of China's national governance system, and public evaluation of the effects of environmental governance is essential to the theory and improvement of environmental governance. In the context of Public Private Partnership (PPP) reform, both government and enterprises are service providing subjects. Who can be trusted more? And who can improve the public evaluation of environmental governance? These questions have not been answered in the existing research. This research conducted a survey experiment and took the sanitation reform of City H as an example to explore the influence of different governance subjects on environmental governance evaluation, and verified the mediated effect based on the KHB method. The results showed that, first of all, the respondents who received the intervention of enterprise governance text had a higher environmental governance evaluation, rating 0.110 5 higher than the government. Secondly, public trust in enterprises had a mediated effect, with 25.48% contributed from the effect between governance subjects and environmental governance evaluation. Thirdly, the perception of environmental performance also played a mediated role with 17.98% of its effects. Finally, media use also had a positive mediated effect. This article suggests that PPP reform should give more priorities to enterprises. The government should strengthen its involvement in financing, bidding, operation and regulation. It also needs to improve information transparency and media publicity. [ABSTRACT FROM AUTHOR]

Objective To investigate the correlation between insomnia and sleep quality in adolescents. Methods According to insomnia Severity index (iSi) Chinese Version, 3342 students technician training in school were divided into non insomnia group (N = 2345) and insomnia group (N = 997). Sleep and emotional state were assessed by iSi Chinese Version, Pittsburgh Sleep Quality index (PSQi), Epworth Sleepiness Scale (ESS), Self - Rating Anxiety Scale (SAS) and Beck Depression inventory (BDi). The social demographic data were collected simultaneously. Results The number of insomnia, daytime sleepiness, anxiety and depression in the population was 997 (29.83%), 568 (17.00%), 243 (7.27%) and 1287 (38.51%), respectively. The comparison of social demographic data between 2 groups showed that the proportion of female (P = 0.000), poor physical condition (P = 0.000), non-only child (P = 0.006), high learning pressure (P = 0.000) and smoking (P = 0.027) in insomnia group were significantly higher than those in non insomnia group. The total scores of iSi Chinese Version (P = 0.000), ESS (P = 0.000), SAS (P = 0.000) and BDi (P = 0.000) in insomnia group were significantly higher than those in non insomnia group. Pearson correlation analysis showed that ISI Chinese Version and PSQI scores were positively correlated with ESS score (r = 0.361, P = 0.000; r = 0.064, P = 0.000), SAS score (r = 0.326, P = 0.000; r = 0.069, P = 0.000) and BDI score (r = 0.529, P = 0.000; r = 0.067, P = 0.000), and ISI Chinese Version had higher correlation (r = 0.300-0.600) with the above scores than PSQI (r < 0.100). Further partial correlation analysis showed that ISI Chinese Version score was negatively correlated with PSQI score (r = - 0.056, P = 0.001). Conclusions Higher proportion of female, worse physical condition, more non - only child, greater learning pressure and higher smoking rate were observed in insomnia group. Daytime sleepiness, anxiety and depression in insomnia group were more serious than those in non insomnia group, but PSQI score can not distinguish the above differences. Compared with PSQI, ISI Chinese Version is more closely related to daytime sleepiness, anxiety and depression, and might be more suitable for assessing insomnia in adolescents. [ABSTRACT FROM AUTHOR]

Although freeze-thaw cycles can alter soil physical properties and microbial activity, their overall impact on soil functioning remains unclear. Soil experiencing freeze-thaw is more vulnerable to become erosion material source of erosion, thereby increasing the severity of a variety of soil erosion. In order to reveal the influence of freeze-thaw effects on soil erosion by water, in this paper we quantitatively tested the hypothesis that soil freeze-thaw processes significantly increase the potential for soil erosion by water during rainfall-runoff events. The freeze-thaw cycles detection system and simulated rainfall equipment were used for the experiment. Control test was designed as an unfrozen soil with air-dried. The experimental design involved four simulated rainfall intensities (25, 50, 75 and 100 mm/h), two freeze-thaw cycles (FTC=3 and 6) and two kinds of soil moisture mass fraction (10% and 20%) on four 0.5-m-long, 0.2-m-wide, and 0.1-m-deep soil boxes set at 5% slope. Experiments were conducted at the USDA-ARS National Soil Erosion Research Lab. Surface soil (0-10 cm) materials from a Crosby-Miami complex alfisol with 20% clay, 66% silt and 14% sand from the Purdue Animal Science Research and Education Center in West Lafayette, Indiana. The test soil was air-dried, crushed and passed through an 8-mm sieve, and then experienced the designed freeze-thaw pattern. A 100-min continuous rainstorm was applied. The storm consisted of four intensity sequences: 50 mm/h for 60 min, 25 mm/h for 20 min, 75 mm/h for 10 min and 100 mm/h for 10 min. Runoff samples were collected in 1-L HDPE bottles every 5 min during the two lower intensity rains and every 3 min during the two higher intensity rains. Time to fill the runoff bottle was recorded. After each run, the sample bottles were weighed immediately to obtain the runoff rate. Approximately 5 mL of saturated alum solution was added to the sample bottles to flocculate the suspended sediment. After settling overnight, the excess water was poured off the bottles. The bottles were placed in the oven set at 105 °C for at least 24 h or until the sediments were dried. Dry weights were then taken to calculate the sediment delivery rate and concentration. The results showed that all kinds of experimental treatments could increase runoff and sediment yield intensity under the same rainfall intensity compared with the control test, and sediment yield intensity increased significantly greater than runoff generation intensity. Runoff generation intensity and sediment yield intensity increased with increasing soil moisture mass fraction when freeze-thaw cycles and rainfall intensities were same. The variation of runoff generation intensity and sediment yield intensity with freeze-thaw cycles were relatively complex. Runoff generation intensity and sediment yield intensity increased with increasing freeze-thaw cycles when soil moisture mass fraction was 10%. When soil moisture mass fraction was 20%, runoff generation intensity and sediment yield intensity decreased with increasing freeze-thaw cycles. When soil moisture mass fraction was 10%, and the freeze-thaw cycles both were 3 and 6, total runoff generation amount increase were 3.52% and 4.71%, respectively, total sediment yield amount increase were 6.13% and 16.95%, respectively. When soil moisture mass fraction was 20%, and the freezing and thawing cycles both were 3 and 6, total runoff generation amount increase percentage were 10.24% and 5.01%, respectively, total sediment yield amount increase were 81.99% and 53.07%, respectively. Under the same rainfall intensity, impact of soil moisture mass fraction on runoff generation intensity and sediment yield intensity was big, and the impact of freeze-thaw cycles on runoff generation intensity and sediment yield intensity was relatively small. This paper can provide an insight for the mechanism of freeze-thaw erosion. [ABSTRACT FROM AUTHOR]

Although polyacrylamide and other manufactured soil amendments have been effective in runoff and sediment reduction, there is a need to seek natural products that may provide the same soil conservation benefits. In the process of developing green biomass utilization, such as fiber extraction, the plant juice becomes a natural byproduct because only water is used in the extraction. In this research, corn stalk juice was tested for its effects on runoff generation intensity and sediment yield intensity. The experimental design involved four simulated rainfall intensities (25, 50, 75, and 100 mm/h), four diluted corn stalk juice concentrations (10%, 25%, 50%, and 75%), and two diluted corn stalk juice amounts (400 and 800 g) on four 0.5-m-long, 0.2-m-wide, and 0.1-m-deep soil boxes set at 5% slope. Experiments were conducted at the USDA-ARS National Soil Erosion Research Lab. Surface soil (0-10 cm) of a Crosby-Miami complex alfisol with 20% clay, 66% silt and 14% sand was from the Purdue Animal Science Research and Education Center in West Lafayette, Indiana. The test soil was air-dried, crushed and then passed through an 8-mm sieve. The corn stalk juice used in this study was extracted from field corn plants grown at Purdue Agronomy Farm at West Lafayette, Indiana. A 100-min continuous rainstorm was applied. The storm consisted of four intensity sequences: 50 mm/h for 60 min, 25 mm/hfor 20 min, 75 mm/h for 10 min and 100 mm/h for 10 min. Runoff samples were collected in 1-liter HDPE bottles every 5 min during the two lower intensity rains and every 3 min during the two higher intensity rains. Time to fill the runoff bottle was recorded. After each run, the sample bottles were weighed immediately to obtain the runoff rate. Approximately 5 mL of saturated alum solution was added to the sample bottles to flocculate the suspended sediment. After settling overnight, the excess water was poured off the bottles. The bottles were placed in the oven set at 105°C for at least 24 h or until the sediments were dried. Dry weights were then taken to calculate the sediment delivery rate and concentration. The results showed that all kinds of diluted corn stalk juice applications and concentrations reduced runoff generation intensity and sediment yield intensity. Sediment reduction benefit was greater than the corresponding runoff reduction benefit under the same diluted corn stalk juice application and concentration. When diluted corn stalk juice application was 400 g, runoff reduction ratio was 31.243%, 31.685%, 34.595%, 39.475% and sediment reduction ratio was 23.167%, 41.993%, 37.918%, 64.606% with diluted corn stalk juice concentration increasing from 10% to 25%, 50% and 75%, respectively. When diluted corn stalk juice application was 800 g, runoff reduction ratio was 37.583%, 56.433%, 63.170%, 76.360% and sediment reduction ratio was 48.214%, 77.219%, 88.572%, 95.539% with diluted corn stalk juice concentration increasing from 10% to 25%, 50% and 75%, respectively. The relationships of runoff generation intensity and diluted corn stalk juice concentration, sediment yield intensity and diluted corn stalk juice concentration were both established as decreasing exponential function when diluted corn stalk juice application and rainfall intensity were both same. The relationship between sediment yield intensity and rainfall intensity was established as increasing power function when diluted corn stalk juice application and concentration were both same. However, the relationship between runoff generation intensity and rainfall intensity was relatively complex. When diluted corn stalk juice application amount was 400 g, the relationship between runoff generation intensity and rainfall intensity was established as a significant increasing linear function. When diluted corn stalk juice application amount was 800 g, the relationship between runoff generation intensity and rainfall intensity was established as a significant increasing exponential function. This research can provide a new idea for prevention and control of soil erosion by water, and provide a new method for the prevention and control of water erosion desertification. [ABSTRACT FROM AUTHOR]

[Objective] The proper shading rate and timing for Capsicum chinense Jacq. cultivation in tropical area were explored to provide references for its production in Hainan Province. % Method ] Four shading rates of 30% (T3), 50 % (T5), 70% (T7) and 90% (T9) were set with no shading as the control to explore effects of different shading rate on Capsicum chinense Jacq. seedlings in summer and autumn in tropical area based on the analysis on morphological indexes, seedling index, chlorophyll content, soluble protein and Fv/Fm. [Result]The results showed that morphological indexes, seedling index, chlorophyll content and Fv/Fm declined with increased shading rate. Pn was the biggest in T3 during peak time of photosynthesis, demonstrating an inhibitory effect in photosynthesis caused by excessive or less PPFD. Plant height, stem diameter, photosynthetic product, seedling index, chlorophyll content, soluble sugar and Fv/Fm in CK were significantly higher than those in T5, T7 and T9 (P<0.05,the same hereinafter). Relative permeability of plasma in T5, T7, T9 and CK was significantly higher than that in T3 while proline was significantly lower in T5, T7, T9 and CK than that in T3. [Conclusion]A shading net with shading rate of 30% is recommended at noon to alleviate high light intensity damage in Capsicum chinense Jacq. and cultivate vigorous seedlings in summer and autumn. [ABSTRACT FROM AUTHOR]

Convex composite slopes are the common and natural slopes in the Loess Plateau. But researches on loess convex composite slope are limited. To explore sediment yield laws of the loess convex composite slopes in the present erosion situations, the field runoff scouring experiments were conducted, and the effects of vegetation cover on the flow pattern and flow resistance in the process of the runoff erosion occurrence of the loess convex composite slopes were studied. Three water inflow rates with 14, 18 and 22 L/min were involved in this scouring experiment. Three vegetation coverage degrees, 30%, 50%, 70% and two kinds of vegetation spatial locations, the bottom of the up-slope of the loess convex composite slopes and the bottom of the down-slope of the loess convex composite slopes were taken into consideration in the experiment design. Results showed that when the vegetation coverage degree was equal to 70%, and the vegetation was laid in the bottom of the up-slope of the loess convex composite slopes, the flow pattern of the loess convex composite slopes belonged to the slow transition flow. In other cases, the flow pattern of the loess convex composite slope belonged to the turbulent transitional flow. When the vegetation coverage was laid in the bottom of the down-slope of the loess convex composite slopes, the values of Reynolds number of runoff and the Froude numbers of the runoff were relatively large compared to the values when the vegetation coverage was laid in the bottom of the up-slope of the loess convex composite slopes. There are two kinds of runoff resistance representations, one is Darcy-Weisbach friction coefficient, and the other is Manning roughness coefficient. Runoff resistance expressed by Darcy-Weisbach friction coefficient was consistent with that expressed by Manning roughness coefficient in this study. When vegetation coverage was laid in the bottom of the up-slope of the loess convex composite slopes, the parameters of Darcy-Weisbach friction coefficient and Manning roughness coefficient were larger than that when vegetation coverage was laid in the bottom of the up-slope of the loess convex composite slopes. The results of this paper can provide a scientific reference for the research on the erosion and sediment yield mechanism of the loess convex composite slopes under vegetation cover as well as the rational allocation of the vegetation cover in the loess convex composite slopes. [ABSTRACT FROM AUTHOR]

In order to not only maintain image features, but also to accelerate diffusion rate, an adaptive diffusion model is proposed in this paper. In this model, the flat areas, line edges and corners of damaged image can be distinguished according to eigenvalues of the average gradient matrix. Meanwhile, diffusion direction of image information is controlled by average gradient matrix and its eigenvectors. Thus, this model can adaptively select diffusion rate and its direction in different regions so as to maintain the structural characteristics of damaged image. The experimental results demonstrate that this model can speed up the diffusion rate while maintaining the image structure. When it is applied in image inpainting, this model can accelerate the inpainting while the inpainted image is in line with human visual effect. [ABSTRACT FROM AUTHOR]

Carbon storage and its allocation of 7-, 29-and 32-year-old Erythrophleum fordii plantation ecosystems in Guangxi were studied on the basis of biomass survey. The results showed that the carbon contents in different organs of E. fordii, ranging from 509. 0 to 572. 4 g.kg-1, were in the order of stem > branch > root > bark > leaf. No significant differences in carbon content were observed among the shrub, herb and litter layers of the E. fordii plantations with different ages. Carbon content in the soil layer (0-100 cm) decreased with increasing the soil depth, but increased with increasing the stand age. The carbon storage of the arbor layer was 21. 8, 100. 0 and 121. 6 t.hm-2 for 7-, 29-and 32-year-old stands, respectively, and the order of carbon storage allocation in different organs was same as the order of carbon content. The 7-, 29-and 32-year-old E. fordii plantation ecosystems stored carbon at 132. 6, 220. 2 and 242. 6 t.hm-2, respectively. The arbor layer and soil layer were the main carbon pools, accounting for more than 97% of carbon storage in the ecosystem. Carbon storage allocation increased in arbor layer but decreased in soil layer with increasing the stand age. The influence of stand age on carbon storage allocation in shrub, herb and litter layers did not show a obvious regular pattern. [ABSTRACT FROM AUTHOR]

A field experiment on effects of tillage rotation and fertilization on corn continuous cropping-practiced lands was carried out in Heyang of Shaanxi in 2007-2012. The tillage types included annual rotation of notillage and subsoiling (NT-ST), subsoiling and conventional tillage (ST-CT), or conventional tillage and no-tillage (CT-NT), and yearly practice of no-tillage (NT-NT), subsoiling (ST-ST) or conventional tillage (CT-CT). The fertilization treatments included balanced fertilization, low-rate fertilization and conventional fertilization, which were separately practiced against the different tillage types. The experiment investigated compositions, mean mass diameters (MWD), geometrical mean diameters (GMD) and fraction dimension numbers (D) of soil aggregates in 0-40 cm soil and contents of organic carbon in 0-60 cm soil. The results indicated that: 1) The increased tillage intensity caused the reduced mechanical stability and content of soil aggregates and increased soil organic carbon loss. No-tillage or tillage rotation increased the MWD, GMD and contents of soil organic carbon and soil aggregates with diameters of more than 0.25 mm, but decreased D. Under the same fertilization treatment, the contents of soil aggregates with diameters of more than 0.25 mm were ranked in the order of NT-NT>NT-ST>NT-CT>ST-ST>CT-ST>CT-CT, and under the same tillage rotations, the soil aggregates were more stable with the balanced or low-rate fertilization than with the conventional fertilization. 2) Mathematical fractal dimension fitting of soil aggregates indicated that the fractal dimension numbers of soil aggregates ranged within 2.247-2.681 by dry sieving and 2.897-2.976 by wet sieving. In 0-30 cm soil, the fractal dimension numbers of soil aggregates were significantly lower under no-tillage or tillage rotation than under conventional tillage, and in 0-40 cm soil, the fractal dimensions of soil aggregates increased with soil depth, and tended to stabilize at the soil depth of 40 cm. 3) The different fertilization treatments exerted significantly different influences on the contents of soil organic carbon (P<0.05), which tended to decline with soil depth. Compared to the conventional fertilization, the balanced fertilization increased the content of soil organic carbon by 6.9%, and the contents of soil organic carbon increased as the diameters of soil aggregates increased. The correlation analysis showed that the contents of soil aggregates with diameters of 0.25-2 mm significantly affected the content of soil organic carbon, with the coefficient of determination being 0.848 (P<0.01). [ABSTRACT FROM AUTHOR]

This paper studies the security of two-way authentication protocol (PUMAP) based on ultra-lightweight radio frequency identification(RFID) of physical non-cloning functions. After the analysis of the certification process, it is found that the shift digits of the shift operation can be obtained by hacking one certification process, then the formulas in the certification is simplified, and the secret information is obtained by calculating between reader and tags. In addition, this protocol couldn't prevent location tracking attack. The analysis result shows that PUMAP is not secure, and its safety performance really couldn't satisfy the security requirement of RFID systems. [ABSTRACT FROM AUTHOR]

By using fumigation-extraction method and phospholipid fatty acids (PLFAs) analysis, this paper studied the characteristics of soil microbial biomass and community composition in the Erythrophleum fordii, Castanopsis hystrix, and Pinus massoniana plantations in south subtropical China. The soil microbial biomass, total PLFAs, bacterial PLFAs, and fungal PLFAs in the plantations were significantly affected by the plantation type and season, and the soil microbial biomass, total PLFAs, and individual PLFA signatures were higher in dry season than in rainy season. The C. hystrix plantation had the highest soil microbial biomass carbon and total PLFAs, while the E. fordii plantation had the highest soil microbial biomass nitrogen. There was a significant positive correlation between the soil pH and arbuscular mycorrhizal fungal (AMF) PLFA (16:1ω5c). The soil total PLFAs, gram-positive bacterial PLFAs, saprophytic fungal PLFA (18:2ω6,9c), and the ratio of gram-positive to gram-negative bacterial PLFAs were significantly positively correlated with soil organic carbon, total nitrogen, and total phosphorus, suggesting that the soil organic carbon, total nitrogen, and total phosphorus contents were the most important nutrient factors affecting the numbers and types of the soil microorganisms. In addition, the ectomycorrhizae fungal PLFA (18:1ω9c) and AMF PLFA were significantly correlated with the soil C/ N ratio. [ABSTRACT FROM AUTHOR]

Resorting to the huge bandwidth proceeding gain, ultra wideband (UWB) can communicate under ultra low power spectrum, even lower than -41.3 dBm/MHz, which satisfies the requirement of underlay spectrum share mode in cognitive radio, in this condition, the signal transmission spectrum of cognitive radio users will not disturb other primary users. Spectrum management organizations present strict limits to UWB transmission power, as a result, it is very important to design UWB pulse which can meet the need of spectrum mask. Aimed at the shortcomings of existing UWB pulses, a novel UWB pulse with good self correlation characteristic is presented, which can achieve higher spectrum efficiency, reduce the multiple access interference and improve the transmission quality of UWB system. Compared with other UWB pulses which are compliant With the mask, the pulse designed has better performance, and it is not affected by modulation scheme and suitable for any modulation format. [ABSTRACT FROM AUTHOR]