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Copyright of University Chemistry is the property of Peking University, College of Chemistry & Molecular Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

每年有大量的大鸨在新乡黄河湿地鸟类国家级自然保护区越冬,但其种群数量及越冬现状尚不清楚。2015年1月～2017年12月,采用样线法和定点观察法对该地大鸨的种群数量及越冬生态进行了研究,结果如下:(1)大鸨每年11月初迁入新乡黄河湿地,最早观测到大鸨的时间为2015年11月8日; 最晚到达时间为2016年11月19日; 次年3月中旬迁出保护区,飞往繁殖地。(2)在大留寺南北及碾庄,地势平坦开阔,麦田面积较大,距水源较近,距村庄较远,人为干扰相对较少,大鸨的数量最多。(3)每年11月中旬到12月初,大鸨数量呈上升趋势,12月初大鸨的数量达到最高峰,1月初到3月中旬数量逐渐减少,3月底全部迁出保护区。(4)大鸨的觅食地食物非常丰富,每天的8:00 ～10:00和14:00 ～16:00为其取食高峰,主要以啄食农田麦苗为食; 长距离飞翔时,队形大致呈W、V或倾斜的“一”字形。

新乡黄河湿地鸟类国家级自然保护区是多种鸟类迁徙的重要停栖站。为了弄清保护区内鸟类的多样性,2014年1月～2016年12月,采用样线法和样点法,对保护区鸟类种类、数量及栖息地进行了调查。共记录鸟类17目41科126种,其中国家Ⅰ级重点保护鸟类3种,国家Ⅱ级重点保护鸟类18种,列入中日、中澳候鸟保护协定的鸟类分别为62种和13种。居留型:夏候鸟占27.78%,冬候鸟占18.25%,旅鸟及留鸟均占26.98%。区系分析:古北种占54.76%,广布种占32.54%,东洋种占12.70%。沼泽水域的Shannon-Weaver指数、Pielou均匀性指数均高于荒滩草地及村庄农田。G-F指数法表明村庄农田的鸟类在科属水平上多样性最高,荒滩草地的鸟类组成上单种科较多。沼泽水域与其他两种生境的鸟类群落相似性较低,荒滩草地与村庄农田的鸟类组成相似性较高。鉴于保护区位于人口稠密地区,鸟类面临着较大的生存压力,为此提出了一些保护性建议。

Copyright of Journal of Clinical Hepatology / Linchuang Gandanbing Zazhi is the property of Journal of Clinical Hepatology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To establish the intelligent identification method for the big data of liver injury-related adverse drug reaction（ADR） based on the construction of text database. Methods With the keywords including “drug-induced liver injury” and “abnormal liver function” and a search time of January 1, 2012 to December 31, 2016, 5%（4152 cases） of the case reports of liver injury-related ADR were retrieved and extracted from the China Adverse Drug Reaction Monitoring System, and then based on clinical reevaluation by physicians, these cases were classified into “negative cases”, “suspected cases”, and “confirmed cases”. On this basis, key elements（including ADR name, biochemical parameter, and clinical symptoms） were identified. An intelligent identification method for liver injury-related ADR was established based on the correlation analysis between key elements and clinical reevaluation and the receiver operating characteristic（ROC） curve for determining cut-off values, and the method of cross validation was used to evaluate the performance of this intelligent identification method. Results The formula for the evaluation and identification of liver injury-related ADR was as follows: total score（M）=symptom score+index score+ADR name score. This formula showed the best discriminatory ability to distinguish “negative case” from “suspected case” or “confirmed case” at M=5（area under the ROC curve [AUC]=0.97）, with a sensitivity of 99.57% and a specificity of 84.61%, and it showed the best discriminatory ability to distinguish “confirmed case” from “suspected case” or “negative case” at M=12（AUC=0.938）, with a sensitivity of 87.93% and a specificity of 85.98%. Conclusion This method provides reference and basis for intelligent identification and evaluation of big data on liver injury-related ADR and is expected to effectively reduce the burden of manual processing of ADR big data and provide effective tools and methodological demonstration for early risk signal identification and warning of liver injury-related ADR. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Clinical Hepatology / Linchuang Gandanbing Zazhi is the property of Journal of Clinical Hepatology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ObjectiveTo investigate the drugs responsible for drug-induced liver injury (DILI) in children and related risk factors, and to provide a reference for safe drug use in children in clinical practice. MethodsA retrospective analysis was performed for the clinical data of 187 children with DILI, aged 0-14 years, who were treated in The Fifth Medical Center of Chinese PLA General Hospital from January 2008 to December 2017, including medication history, biochemical parameters, symptoms/signs, and clinical outcome. Based on the method of integrated evidence chain, 127 children with medication information were divided into Western medicine-induced DILI group (Western medicine group with 75 children), traditional Chinese medicine (TCM)-induced DILI group (TCM group with 15 children), and the group with DILI induced by Western medicine and TCM (TCM-Western medicine group with 37 children). The reason for medication, medication time, latency of DILI, and drug classification were compared between groups. The Kruskal-Wallis H test was used for comparison of continuous data with skewed distribution between multiple groups, and the Nemenyi test was used for further comparison between two groups; the chi-square test was used for comparison of categorical data between groups. ResultsOf all 187 children with DILI, 116 (62%) had severe liver injury or above, among whom 3 underwent liver transplantation and 1 died, and 45 (24%) developed chronicity. In the Western medicine group and the TCM-Western medicine group, major suspected drugs for DILI were antibiotics, antipyretics, analgesics, and anti-inflammatory drugs, which accounted for 42%, 30%, 56%, and 31%, respectively. In the TCM group, the most common TCM drugs for DILI were those used to treat skin diseases, which accounted for 47% and were mainly the preparations of Fallopia multiflora (33%). There were significant differences between the three groups in medication time (H=11.658, P=0.003) and latency (H=10.945, P=0.004), and the TCM group had significantly longer medication time and latency than the other two groups (all P＜0.05). ConclusionMost children with DILI have serious conditions. The risk of liver injury due to medication in children should be taken seriously, and particular emphasis should be placed on the risk of liver injury caused by antibiotics, antipyretics, analgesics, and anti-inflammatory drugs and long-term use of some TCM drugs for skin diseases. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Resources & Environment / Nongye Ziyuan yu Huanjing Xuebao is the property of Journal of Agricultural Resources & Environment Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

High pulsed electric field (HPEF) pretreatment is helpful to induce breakdown and displacement effect in cell of fruits and vegetables, which is useful to improve drying speed. We should study the effect of HPEF on the physical properties of fruits and vegetables, which puts the base for optimizing the parameters and mechanism analysis. In this study, 2 kinds of fruits and 2 kinds of vegetables, apple, pear, potato and radish were chosen as raw material. The moisture contents of apple, pear, potato and radish were approximately 86.89%, 89.46%, 78.35% and 93.61%, respectively. Immediately before measuring, the fruits and vegetables were washed and peeled by hand, and then cut into 13 mm diameter and 5 mm thickness using a cork borer. High pulsed electric field generator was used for the HPEF pretreatment of the fruits and vegetables, and the parameters were set as follows: 1) 1 000 V/cm pulse strength, 60 ?s pulse length, pulse number of 15, 2) 1 250 V/cm pulse strength, 90 ?s pulse length, pulse number of 30, and 3) 1 500 V/cm pulse strength, 120 ?s pulse length, pulse number of 45. After HPEF pretreatment, the dynamic viscoelasticity behavior was performed with DMA testing machine using compression platen (diameter of 15 mm). The linear viscoelastic range (LVR) was determined through stress sweeps. A constant amplitude of 10 μm was then chosen (common to the LVR of all samples) to obtain the mechanical spectra as frequency sweeps from 1 to 100 Hz at 25 ℃ and temperature sweeps from 25 to 90 ℃ at 10 Hz. The test and analysis of dynamic viscoelastic of fruits and vegetables were performed by TA Universal Analysis software. Analysis of variance was applied to the data. In order to study the differences among samples, all the data were analyzed with the use of SAS (statistical analysis system) software (version of 9.2). The microstructure analysis was performed by scanning electron microscopy (SEM) on apple samples with the 3 sets of pretreatment parameters, and untreated samples. The storage modulus, loss modulus and loss tangent on different HPEF pretreatment parameters and different oscillation frequency were plotted to characterize the viscoelastic behavior. The theoretical analysis about dynamic viscoelastic mechanics was presented. Results showed that all samples showed a slight linear increase in storage modulus, loss modulus and loss tangent as frequency diminished. A statistically significant difference in storage modulus, loss modulus and loss tangent between different varieties was confirmed. For apple samples, the HPEF pretreatment led to the decrease of storage modulus and loss modulus by 72.36% and 78.09%, respectively. It was primarily attributed to the changes of the cell structure and the intracellular space of the cell as revealed by the SEM. The same decreasing tendency of storage modulus and loss modulus with the increasing of HPEF parameters was observed for potatoes. However, the radish showed a contrary tendency that the storage modulus and loss modulus of radish tissue increased with the increasing of HPEF parameters. High cell turgor pressure may be the main reason for the increase in radish dynamic viscoelasticity after HPEF pretreatment. To pears, as HPEF pretreatment parameters were 1 000 V/cm pulse strength, 60 ?s pulse length, and pulse number of 15, the storage modulus and loss modulus of pear tissue reached the maximum. The reason may be the changes in pear cell turgor pressure caused by low HPEF pretreatment, and then with the further increasing of the HPEF parameters, pear cell membrane could be damaged and the dynamic viscoelasticity of pear tissue decreased. With the temperature increasing, the storage modulus of apple, pear, potato, and radish decreased by 34.44%±3.47%, 49.04%±10.64%, 28.12%±10%, and 55.25%±5.61%, respectively. The loss modulus of them decreased by 66.49%±8.05%, 82.12%±15.12%, 44.66%±7.79%, and 67.84%±2.54%, respectively. These results can provide useful information for the optimization of drying process parameters and the improvement of the industrial pretreatment technique in vacuum freeze-drying processing. [ABSTRACT FROM AUTHOR]

Millet is one of the most important special crops in arid and semi-arid north region of China. It has the features of strong tolerance to drought and barren soil, high nutritional value, and wide adaptability, and therefore becomes an important part of industry structure development for specialty crop in China. As people adjust their diet structure, millet has increasingly become an essential and high quality food on the dining table. However, the limited development in mechanization of millet production equipment has significantly restricted the development of millet industry. Millet can be mechanically damaged due to the friction in the processes of seeding, harvesting, milling, storage and transportation. So it is important to understand the friction characteristics of millet and use the friction parameters for the design of equipment during the above processes and applications of related technologies. The previous research on grains’ friction characteristics was mostly about big grain kernel and small grain kernel like millet has been rarely studied. In this research, a typical millet, Jingu-21, produced in Shanxi Province, was selected as test material with 4 moisture content treatments of 10.7%, 13.7%, 16.0% and 19.8%.. The parameters of friction characteristics of millet including repose angle, coefficient of sliding friction and coefficient of internal friction were measured using a test device of repose angle, a test device of sliding friction and a direct shear apparatus. Variations of the friction characteristics affected by moisture content, contact material and shear velocity were quantified and modeled. The results showed that the moisture content ranging from 10.7% to 19.8% did not significantly affect the size and shape of millet grains, which in turn were not significant factors influencing the friction characteristics of millet. The friction between millet and contacting surfaces was mainly caused by the meshing of concave and convex surfaces and the adsorption of millets. Moisture content had a significant effect on repose angle of millet, which increased from 27.32° to 28.43°. The coefficient of sliding friction linearly increased as the moisture content increased, and the coefficients of static/dynamic sliding friction between millet and steel, iron and acrylic were 0.185-0.290/0.169-0.278, 0.212-0.336/0.190-0.319 and 0.190-0.312/0.182-0.302, respectively. The coefficient of sliding friction of millet against iron plate was the highest, while that against steel plate was the lowest. In the terms of friction reduction, the mechanical parts contacting with millet, such as metering device, should adopt steel material. The internal friction coefficient of millet was not affected by the shear velocity (P>0.05), but linearly increased as the grain moisture content increased, and decreased significantly as the normal stress increased (P<0.01). The coefficient of internal friction of millet decreased quadratically as the normal stress increased, and tended to be stable when the vertical stress was higher than 150 kPa. When the shear velocity was 4.8 mm/min, the normal stress was 50-200 kPa, and the moisture content was 10.7%-19.8%, the coefficient of internal friction of millet ranged from 0.501 to 0.639. In order to improve the flow characteristics of millet in the processes of seeding, storage and transportation, the moisture content should be reduced and the normal stress be increased appropriately. The above results were analyzed using the statistical regression and the mechanical performance parameters of millet on friction were established as test elements respectively. The study can provide a theoretical basis for the design and development of millet mechanization equipment. [ABSTRACT FROM AUTHOR]

Compared with other drying methods, vacuum freeze-drying (VFD) has better rehydration property, which can keep the original quality and color to the maximum extent, and has broader application prospects in such fields as food, medicine and biological products. In order to realize the on-line monitoring of moisture ratio, it is important to research the rules of moisture diffusion and the parameter optimization of VFD process within fruits and vegetables. In this paper, the drying ratio in VFD process was expressed with the change of porosity for fruits and vegetables based on Lattice Boltzmann Method (LBM). During the VFD process, ice crystals' sublimation begins at the material surface, and then goes into the inside gradually; the drying layer gets thicker and thicker, and the frozen layer thinner and thinner. Accordingly, the porosity in different parts of the material is different: the porosity at the edge expands quickly with the earliest sublimation and the value is the biggest at last, while the porosity at the center stays stable, and its value is the smallest. Based on the analysis of VFD process of fruits and vegetables, the paper constructed a square porous media model. The porosity of the model was variable, and the model presumed that the porosity increased linearly from the center to the edges during the drying procedure. By using the LBM combined with the conservation laws of mass, momentum and energy, the VFD velocity distribution in the model was simulated. The results showed that the bigger the change of porosity, the higher the VFD velocity, which suggested that the change of porosity in porous media can express the drying rate in VFD process. Then the experiment took apples as samples to validate the results in the simulation. Cleaned and peeled, apples were cut into 10 mm × 17 mm × 17 mm rectangular samples by a sharp self-made knife and frozen in a refrigerator at -40℃ for 10-12 h. In a VFD machine, through the built-in computer in the machine and on-line moisture measurement system connected to the machine, the real-time data of drying apples were collected and the curve of drying was drawn. In different drying stages of apples (1, 3, 5 and 7 h), the distance between 4 different positions at water boundary and sample edge was measured with vernier calipers, the electron microscope scanning was used to observe apple samples surface, and the porosity of apples in different water boundary was got with the help of image processing software Photoshop 2015 and Matlab 7.0. Origin 8.5 software was adopted to analyze the correlation relationship between the location of water boundary and the porosity of apples with experimental data. The results found that the porosity of apples increased linearly from the center to the edges during the drying procedure. Origin 8.5 software was also adopted to analyze the correlation relationship between the moisture ratio and the porosity of apples with experimental data. The mathematical function between the drying rate and the change of porosity was deduced on the basis of the relationship between the moisture ratio and the porosity. The results found that the bigger the change of porosity, the higher the VFD velocity. All the results in the experiments were consistent with those in the simulation, which proved that the change of porosity of apples can express drying rate in VFD process and LBM can be used to analyze moisture migration diffusion and distribution in VFD process. The conclusions not only provide basis for parameter optimization of VFD process of fruits and vegetables, but also offer application infrastructure for on-line monitoring of moisture ratio. [ABSTRACT FROM AUTHOR]