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为探索食用葵花籽清选、分级、选种、定价的理论依据，完善建立葵花籽的离散元法分析模型，对食用葵花籽的主要尺寸及均齐性进行了分析。选择内蒙古自治区主栽的3个品种食用葵花籽（1013、SH361、SH363）为研究对象，使用统计学方法，以籽粒的三轴尺寸(长度、宽度、厚度)、平均径（算术平均径、几何平均径）、百粒重为指标，分析葵花籽三轴尺寸的统计分布特性、均齐性以及平均径与百粒重的关系，并按宽度对葵花籽进行了清选分级试验。结果表明：不同品种葵花籽的三轴尺寸均服从正态分布并存在线性相关，且总体上存在显著性差异；葵花籽的均齐性存在差异且其几何平均径、算术平均径与百粒重的变化趋势一致；1013品种选用圆孔筛10 mm和8 mm规格，SH361和SH363品种选用圆孔筛10 mm和8.5 mm规格时，分级效果满足要求。In order to explore the theoretical basis for cleaning, grading, selection, pricing of sunflower seeds, and improve the discrete component analysis model of sunflower seeds, the main dimensions and homogeneity of edible sunflower seeds were analyzed. The three typical edible sunflower seeds (1013, SH361, SH363) planted in Inner Mongolia Autonomous Region were used as research objects, and the statistical distribution characteristics of the three-axis sizes, homogeneity and relationship between average diameter and hundred-grain weight of the sunflower seeds were analyzed with the three-axis size(length, width and thickness), mean size(geometric mean diameter, arithmetic mean diameter) and hundred-grain weight as indexes. The width grading test of sunflower seeds was carried out. The results showed that the three-axis sizes of different varieties of sunflower seeds followed a normal distribution and were linearly correlated with significant differences in general. The homogeneity of sunflower seeds was different, and its geometric mean diameter, arithmetic mean diameter and hundred-grain weight had the same changing trend. When round hole sieves of 10 mm and 8 mm were used for 1013, and round hole sieves of 10 mm and 8.5 mm were used for SH361 and SH363, the grading effect could meet the requirement.

BackgroundAs an excellent nondestructive testing technology, cold neutron radiography is widely employed to image materials of interest in many basic and application research fields. One of key components of such device is the neutron sensitive scintillation screen. Normally, these screens are made up of scintillation or phosphor powder mixed with/without neutron sensing isotopes, such as 6LiF:ZnS(Ag) and Gd2O2S:Tb. Uniform scintillation screens are very difficult to make a trade-off between spatial resolution and neutron detection efficiency. Recently a new type of micro-structural scintillation screens has been proposed, which is expected to have higher spatial resolution while maintaining higher neutron detection efficiency. Following this idea, a scintillation screen has been proposed, developed, and studied by our group.PurposeThis study aims to develop a new type of scintillation screens based on a glass capillary array filled with scintillation powders to achieve high spatial resolution and neutron detection efficiency.MethodsFirst of all, a neutron sensing scintillation screen was made by filling very fine grinded Gd2O2S:Tb phosphor powder into glass capillary arrays. Three main steps, i.e. the phosphor powder grinding, the particle size screening, and the vacuum suction filtration process, were taken making such screens. Then, photographs of Gd2O2S:Tb phosphor before and after grinding were taken with a scanning electron microscope (SEM) to examine the filling efficiency of scintillation powder in the glass capillary arrays. Finally, experimental test of spatial resolution of such scintillation screens was carried out by using an optical system to read out the scintillation light emitted by the screen, and a Siemens Star neutron test target to characterize the screens' spatial resolution with cold neutrons.ResultsX-ray luminescence spectra show that the grinding process reduces the light yield of the phosphor. The filling efficiency of scintillation powder in the glass capillary arrays is up to 70%. The cold neutron imaging system with developed scintillation screen achieves spatial resolution of about 300 μm@CTF=3% by experimental test.ConclusionsAlthough the new neutron sensing scintillation screen is still under-developing and there are still some problems to be overcome, cold neutron imaging scintillation screen based on glass capillary array filled with Gd2O2S:Tb phosphor, proposed in this study, can be used to achieve high spatial resolution and neutron detection efficiency with advantages of low cost and simple fabrication process.

Objective We aimed to explore the mechanism of action of cervical transverse process tip acupuncture in a rat model of posterior circulation ischemic vertigo (PCIV) based on the G protein-coupled receptor (Mas)/protein kinase A(PKA)/cyclophosphoadenosine effector binding protein (CREB) pathway. Methods According to the random number table method, 32 male SD rats were divided into the sham operation group (n=8), the model group (n=8), the nimodipine group (n=8), and the electroacupuncture group (n=8). In all groups except for the sham operation group, the PCIV model was established by ligating the right common carotid artery (CCA) and the right subclavian artery (SCA). In the sham operation group, only the right CCA and the right SCA were removed and sutured directly without ligation. The nimodipine group was given intragastric administration of nimodipine suspension (12 mg/kg), and the electroacupuncture group selected C2, C4, and C6 transverse process tip for acupuncture, and performed electroacup uncture treatment on both sides of C2 and C6, 20 minutes each time. There was no intervention in the sham operation group and the model group. The intervention was given once a day for 14 days. Cerebral blood flow, the decrease decline rate of cerebral blood flow, and the step-down avoidance time were recorded in each group. Apoptosis of neurons in the vestibular nucleus of the right brainstem was observed by TUNEL staining, and the protein expression levels of Mas, PKA-Ca, CREB, p-CREB, Bcl-2, and Bax in the vestibular nucleus of the right brainstem were determined by Western blotting. Results Before intervention, compared with the sham operation group, cerebral blood flow in the right vestibular nucleus was decreased and decline rate of cerebral blood flow in the right vestibular nucleus was increased in the remaining three groups (P<0.05), which suggested that the model was successfully established. After intervention, compared with the sham operation group, the model group showed lower cerebral blood flow in the right vestibular nucleus, larger decline rate of cerebral blood flow in the right vestibular nucleus, apoptosis rate in the vestibular nucleus of the right brainstem and protein expression level of Bax increased, and reduced protein expression levels of Bcl-2, Mas, PKA-Ca, and p-CREB/CREB (P<0.05). Compared with the model group, the electroacupuncture group and the nimodipine group showed increased cerebral blood flow in the right vestibular nucleus, a smaller decline rate of cerebral blood flow in the right vestibular nucleus, a shorter step-down avoidance time, a decrease in apoptosis rate in the vestibular nucleus of the right brainstem, decreased protein expression level of Bax, and increased protein expression levels of Bcl-2, Mas, PKA-Ca, and p-CREB/CREB (P<0.05). Compared with the nimodipine group, the electroacupuncture group had increased cerebral blood flow in the right vestibular nucleus, a smaller decline rate of cerebral blood flow in the right vestibular nucleus, a shorter step-down avoidance time, a decrease in apoptosis rate in the vestibular nucleus of the right brainstem, decreased protein expression level of Bax, and increased protein expression levels of Bcl-2, Mas, PKA-Ca, and p-CREB/CREB (P<0.05). Conclusion Cervical transverse process tip acupuncture can effectively inhibit apoptosis in the vestibular nucleus in rats with PCIV. Its mechanism may be related to improving cerebral blood flow of the vestibular nucleus and activation of the Mas/PKA/CREB signaling pathway, followed by the modulation of the levels of relevant proteins to inhibit apoptosis in the vestibular nucleus. [ABSTRACT FROM AUTHOR]

Background Measurement of uranium and plutonium content in the waste drum assay system (WDAS) is affected by the absorption of the matrix in the drum due to the neutron coincidence counting of waste. Purpose This study aims to propose a method for correcting neutron coincidence counting applicable to the classification detection of WDAS. Methods First of all, the calibration function between the absorption correction factor of the external neutron source and the sample in the waste drum was established. Then the coincidence neutron count of plutonium in the waste drum was corrected according the calibration function. Thereby the activity and quality of α waste were accurately measured. Finally, a 252Cf source was taken as external neutron source for experimental verification of neutron absorption correction of WDAS. Results Experimental results show the relative deviation between the corrected 252Cf activity and the standard value is significantly reduced, and the deviation of the experimental correction results is better than 7%. Conclusions The absorption correction method improves the accuracy of the results and provides the basis for the extension and application of the device.

Productivity is one basic property of farm land and the spatial pattern can be used as the baseline information in making and implementing appropriate agricultural policies. As an important winter wheat production area of China, food production in the Huang-Huai-Hai region has been receiving considerable attention for a long time. The Normalized Difference Vegetation Index (NDVI) derived from remote sensing techniques is a widely utilized vegetation index in assessing agricultural land distribution, productivity and crop growth conditions. The NDVI time series can be disaggregated into a set of quantitative metrics reflecting crop distribution and growth phenology. However, few studies take both mean crop yield and its inter-annual variability into account in evaluating the productivity of wheat land. In the present paper, we proposed a method to evaluate wheat productivity by using annual NDVI indices derived from the time series of10 years MODIS NDVI data over the Huang-Huai-Hai region. The calculated productivity can be used to monitor farmland quality. The proposed method composed of four steps: Firstly, we analyzed the reconstructed NDVI time series to generate a set of phenology indices; Secondly we extracted the distribution of winter wheat in the study area using the decision tree classifier; Thirdly we ranked each growing season's mean NDVI(NDVImean) of winter wheat cultivated area from reviving to maturity stage into five levels and the Coefficient of Variation(C.V) of ten years NDVImean into four levels; Lastly, we evaluated the winter wheat land productivity by applying a criterion established by both mean rank and C.V level. The extracted wheat planted areas were consistent with the wheat sown area obtained from the statistic database at the county and provincial scale. The statistically significant correlation between the NDVImean and yields as calculated from the statistic database at the county levels suggested that the mean rank for ten years' NDVImean could indicate the yield level, whereas the C.V of the rank could measure the variation of yield within ten years. The relationship between the mean rank and the C.V for each 20 km×20 km grid showed that in most parts of the wheat land, the high ranked mean yield area had low temporal variations and the low rank's variations were high. It means the high variation of yield is related to a low productivity as well as a low yield level. Consequently, combining mean yield level and its inter-annual variability can generate more objective information for cropland productivity. The result showed that the percentage of high, middle and low level wheat land was 18.35%, 40.04% and 41.61% respectively, which suggested that there is still great potential to improve the winter wheat productivity in the study area. The spatial productivity pattern was driven by variations in hydrothermal condition, soil properties and water resources. The high productivity wheat lands were mainly located in the Huang-Huai Plain where hydrothermal condition is suitable for winter wheat. The low productivity lands were in Jin-Lu-Yu low Plain where drought is more likely to happen in spring, which is the key stage for winter wheat growth. Areas where wheat is low productive caused by infertile soil and water shortage, especially in Saline-alkali land, should be investigated in the future studies to help stabilize and increase grain yield in Huang-Huai-Hai region. [ABSTRACT FROM AUTHOR]

Spike recorded by multi-channel microelectrode array is very weak and susceptible to interference, whose noisy characteristic affects the accuracy of spike detection. Aiming at the independent white noise, correlation noise and colored noise in the process of spike detection, combining principal component analysis (PCA), wavelet analysis and adaptive time-frequency analysis, a new denoising method (PCWE) that combines PCA-wavelet (PCAW) and ensemble empirical mode decomposition is proposed. Firstly, the principal component was extracted and removed as correlation noise using PCA. Then the wavelet-threshold method was used to remove the independent white noise. Finally, EEMD was used to decompose the noise into the intrinsic modal function of each layer and remove the colored noise. The simulation results showed that PCWE can increase the signal-to-noise ratio by about 2.67 dB and decrease the standard deviation by about 0.4 μV, which apparently improved the accuracy of spike detection. The results of measured data showed that PCWE can increase the signal-to-noise ratio by about 1.33 dB and reduce the standard deviation by about 18.33 μV, which showed its good denoising performance. The results of this study suggests that PCWE can improve the reliability of spike signal and provide an accurate and effective spike denoising new method for the encoding and decoding of neural signal.

Vasculogenic mimicry (VM) is a brand-new tumor vascular pattern with the ability to form vessel-like networks without participation of endothelial cells and independent on angiogenesis. It can provide adequate blood supply for tumor growth. The formation of VM involves multiple molecule mechanisms and signal pathways, including cancer stem cell and epithelial-mesenchymal transition. As a unique blood-supply pattern, VM is associated with cancer invasion, metastasis and poor prognosis. Because of its important role in cancer progression, VM will become a new target for therapy of cancers.

Objective: To study the changes in quantitative kinetic parameters in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) during radiotherapy and their value for efficacy evaluation in patients with nasopharyngeal carcinoma (NPC)., Methods: Twenty-four patients with NPC that had been pathologically confirmed as poorly differentiated squamous cell carcinoma underwent conventional MRI and DCE-MRI scans 1-2 days before radiotherapy (Pre-RT), during radiotherapy (RT 50 Gy), and upon completion of radiotherapy (RT 70 Gy). Based on the two-compartment model and using the arterial input function deconvolution technique, we calculated the quantitative kinetic parameters of DCE-MRI (K(trans), kep, and Ve) of the tumor tissues, examined the correlation between the tumor regression rate (RS0-50) and the parameters on Pre-RT and RT 50 Gy, and compared the parameters for RT 70 Gy among the groups with different prognosis., Results: The K(trans) value of the tumor tissue decreased after radiotherapy and showed a significant difference between Pre-RT and RT 70 Gy, but not between Pre-RT and RT 50 Gy. The kep value decreased and Ve value increased after radiotherapy. The tumor regression rate was found to be positively correlated with the K(trans) value for Pre-RT (P=0.005) but negatively with the K(trans) value for RT 50 Gy (P=0.001). During the follow-up for 3 years, 5 patients died and 3 patients had distant metastases. No statistical differences in K(trans), kep, or Ve were found between the groups with different prognosis., Conclusions: The kinetic parameters in DCE-MRI, which vary significantly during radiotherapy, allow monitoring of tumor angiogenesis and vascular permeability and quantitative assessment of treatment efficacy for NPC. K(trans) value for Pre-RT and RT 50 Gy can serve as an indicator for early efficacy assessment of radiotherapy and for treatment adjustment, but its relation with the long-term outcomes awaits further study.

Objective: To evaluate the response rate and adverse reactions of xeloda, an analogue of 5-fluorouracil, in the treatment of relapsed and metastatic breast cancer., Methods: Twenty-two breast cancer patients who had recurrent and metastatic measurable foci were treated from Dec. 1999 to Feb. 2000. Xeloda was given, as a single drug, at a dose of or 2,510 mg/m2/d, bid, for two weeks followed by one week rest as one cycle, at least for one cycle in each patient., Results: Among these 22 patients, there was no complete response. Rates of partial response 8(36.4%), stable disease 10(45.5%), progressive disease 4(18.2%), and clinical benefit response (CR + PR + SD) 18(81.8%). The response rate in patients who had failed in previous chemotherapy of taxanes and/or anthracycline was 30.0%-33.3%. The common adverse reactions were hand-foot syndrome, skin pigmentation, nausea, vomiting, anorexia and fatigue. Mild-moderate anemia and leukopenia were observed in 36.4% of patients. Stomatitis, dizziness, diarrhea and chest distress were present in some. One patient developed degree IV myelosuppression. Total bilirubin and alanine transaminase (ALAT) mild elevation occurred in a few patients., Conclusion: Xeloda is an effective drug in the treatment of patients with relapsed and metastatic breast cancer, especially for those who have failed in chemotherapy with taxanes and/or anthracycline. Xeloda is well tolerated but has mild adverse reactions.