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    中南民族大學學報（自然科學版）

    中南民族大學學報（自然科學版）

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    Journal of South-Central University for Nationalities(Natural Science Edition)
    本刊是自然科學綜合性學術期刊。本刊為季刊，國內外公開發行，16開本，96頁。每季末月30日出版。宗旨是發表自然科學各基礎學科的研究成果，主要發表本院重點學科的研究成果；刊登為經濟建設服務，特別是為民族地區經濟建設服務取得顯著效益的學術論文。特點是立足民院，面向民族地區。注重基礎理論的研究，更注重應用科技的研究；注重論文的創新性，更注重民族地區急需的實用性。
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    • 國內刊號/CN：42-1705/N
      國際刊號/ISSN：1672-4321
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    • 主管單位：國家民族事務委員會
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    中南民族大學學報（自然科學版） >2021年第6期

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    • 摘要：To study the modulation mechanism of traveling planetary wave ionospheric disturbances ( TPWIDs) on F layer during pre-reversal enhancement ( PRE) and its effect on the formation and development of spread F ( SF) , in this paper, the characteristics of planetary wave disturbance is analyzed during the high SF season in china′s low latitude region, and the influence of TPWIDs phase on the formation and development of SF is investigated by the method that TPWIDs are used to refer to oscillation of the true height, which is the day-to-day variability and one of the ionosphere characteristic parameters obtained from ionogram observed by Digital Portable Sounder 4d(DPS-4D) ionosonde at sanya in 2012. The results show that TPWIDs-type oscillations controlling the strength of the electric field during PRE, therefore, slowly push the F layer height up and down according to the TPWIDs phase in the geomagnetic quiet period. the occurrence of SF is strongly controlled by the change of post-sunset F layer height and the altitude of 250 km may be a threshold at sanya, so when the the electric PRE causes the F layer bottom side to reach heights above 250 km, it is conducive to generate SF. Also during equinox ( March, April, September and October) the onset time of SF is modulated by the TPWIDs phase in such way that, when the phase greater, SF occurs earlier and when the phase smaller, SF occurs later or no SF.%為研究在日落后反轉增強( PRE)期間行進式行星波電離層擾動( TPWIDs)對F層的調制機制以及對擴展F(SF)形成和發展的作用,利用三亞地區DPS-4D數字測高儀2012年探測的34080張數字頻高圖數據,獲取了電離層特性參數-真高,以真高的逐日變化表征行進式行星波擾動,分析了中國低緯地區SF高發季節中行星波擾動特性,并研究了行星波擾動時的不同相位對SF產生和發展的影響。結果表明：地磁平靜時期,在PRE期間,TPWID行星波擾動調制著PRE時期的電場強度,根據其相位的不同能導致F層的高度上抬或下降；日落后F層高度的變化控制著SF的發生,在三亞地區真高閾值大約為250 km,即當PRE導致F層高度上抬到大于250 km時,有利于SF產生；并且在分點季節(3月,4月,9月和10月),TPWID行星波相位也調制著SF的開始時間,即TPWID相位越大, SF發生的越早,TPWID相位越小,SF發生的越晚甚至不發生。
    • 摘要：為使在線手寫簽名認證的使用更具實用性，提出了一種基于經驗模態分解( EMD)和奇異值分解( SVD)的在線手寫簽名特征提取方法.針對在線簽名數據的坐標信息，以EMD分解所得的本征模態函數( IMF)分量為初始矩陣，并進行矩陣奇異值分解，以奇異值的能量值作為樣本數據的特征分量構成用戶特征向量，建立了基于支持向量數據描述( SVDD)的一類認證模型驗證該方法效果.在SVC2004簽名數據庫上的實驗結果表明：該方法提取的簽名特征區分明顯，使用少量的單類真實簽名作為訓練樣本，得到FAR=3.38%，取得了較好的認證識別效果.%In order to make the use of on-line handwriting signature verification more practical, this paper presents a feature extraction method based on Empirical Mode Decomposition ( EMD ) and Singular Value Decomposition ( SVD ) . With the help of signatures′coordinate information, the initial feature matrix of Intrinsic Mode Function ( IMF) components decomposed by EMD is SVD transformed, and use the energy value of the first two singular values as the characteristic component of the signature data, then the certification model of one-class identification is established based on Support Vector Data Description ( SVDD) with a small amount of real signature to validate the effect. Experimental results from the SVC2004 signature database show that the characteristics extracted by this method distinguished clearly, and use a small number of one class real signatures as training samples, achieved a better recognition result with FAR=3. 38%.
    • 摘要：This paper proposed a new neural network based super-resolution reconstruction algorithm for blurring face image. The norm based minimum total variation was firstly used to deal with the problem of blurring in low-resolution image. The M images in the training database with the most similar to the initial restored image were following identified according to the structure similarity measure. Then the weighted sum of the M images was calculated for initial output of the neural network. Combining with Bayesian posterior probability, RBF neural network was trained iteratively for finally outputs of the high resolution image. The algorithm took full advantages of the similarity between different face images for reconstruction and the constraints of the minimum total variation for edge singularity and smoothness. The experimental results showed that the algorithm effectively improved the resolution of input low face image and had some practice value.%提出了一種基于神經網絡的超分辨率重構算法。首先用基于l1范數的最小全變分約束對輸入的低分辨率圖像進行去模糊處理，得到初始復原圖像；再根據結構相似度原則選擇初始復原圖像在訓練集中最相近的M幅圖像，并加權求和作為神經網絡的初始輸出；結合貝葉斯后驗概率，用RBF神經網絡進行迭代訓練，最后輸出復原的高分辨率圖像。算法充分利用了不同人臉圖像之間的相似性，并加入了最小全變分約束，以保持圖像邊緣的奇異性及非邊緣的平滑性。實驗結果表明：算法能有效提高下采樣及模糊人臉圖像的分辨率，具有一定的實用價值。
    • 摘要：為優化HTTPS性能，研究了TCP特性對TLS性能的影響。通過數學模型分析，指出了2種不同條件下， TLS Record Size選擇對用戶首數據響應延時( TTFB)、首頁面響應延時( TTFP)、網絡效益、吞吐率等參數指標的影響。大的TLS Record Size提高網絡吞吐和利用率，但增加了用戶首數據響應延時，適合需要高吞吐但響應延時不敏感的場景；小的TLS Record Size降低用戶響應延時卻降低了網絡吞吐和利用率，適合對用戶響應時間敏感的場景。%This paper studies the effect of TCP characteristics on the performance of TLS in order to optimize the performance of HTTPS. Through the analysis of mathematical model, it points out the influence of Record Size TLS selection on the first data response time delay (TTFB), the first page response time delay (TTFP), network efficiency, and throughput rate and other parameters in two different conditions. Large TLS Record Size blocks could improve network throughput and utilization rate, but increase user time to the first byte, which is suitable for the scenes of requiring high throughput but latency insensitive scene, while small TLS Record Size blocks could decrease the user latency but reduce network throughput and utilization rate, which is suitable for user response time sensitive scene.
    • 摘要：In this paper, initial-boundary value problem of a class of degenerate reaction diffusion system was analyzed, and existence conditions of global solution of this system were discussed. It was proved that the global solutions exist while the diameter of region Ω is adequate small, yet the solutions would quench in a finite time while the diameter of Ω is adequate large. The range of diameter of Ω was obtained.%分析了一類退縮反應擴散方程組的初邊值問題，討論了此方程組整體解存在的條件，證明了當區域Ω的直徑適當小時，解是全局存在的；當Ω的直徑適當大時，解會在有限時刻發生猝滅現象，得到了Ω直徑的量化范圍。
    • 摘要：采用原位水熱法制備了LaCoO3/MCF、LaCoO3/SBA-15催化劑,分別采用XRD、氮氣物理吸附-脫附、TEM對催化劑進行了表征,并在固定床反應器中對催化劑的CO氧化反應活性進行了測試,考察了不同LaCoO3負載量和不同載體負載的催化劑的CO氧化性能.結果表明：原位水熱合成法制備的LaCoO3/MCF催化劑具有較高的比表面積(281.1~427.6 m2·g-1)和三維介孔泡沫狀孔道結構,LaCoO3納米顆粒均勻地分散在催化劑中. LaCoO3的含量顯著影響催化劑的CO氧化反應活性,負載量為30%的催化劑(30LaCoO3/MCF)的反應活性最高,CO在387℃氧化完全.與SBA-15負載的催化劑相比,由于 MCF 的三維互通結構,催化劑30LaCoO3/MCF 的催化性能明顯提高.%LaCoO3/MCF and LaCoO3/SBA-15 catalysts were prepared by in situ hydrothermally method. The catalysts were characterized by X-ray diffraction, nitrogen absorption-desorption and TEM. The oxidation of CO was tested on a fixed bed reactor. The influence of the loading of LaCoO3 and the type of carrier were investigated. The results showed that the LaCoO3/MCF catalysts had large surface area (281. 1 ~ 427. 6 m2 ·g-1) and well retained 3-D mesoporous foamy channels. The nano-sized LaCoO3 particles were uniformly dispersed in the catalyst. It also showed that the content of LaCoO3 had significant effect on the oxidation of CO. The 30LaCoO3/MCF catalyst , with 30%( mass fraction) load of LaCoO3 on MCF, showed the best activity and CO was oxidated completely up to 387℃. Compared with the 30LaCoO3/SBA-15, the 30LaCoO3/MCF catalyst had better catalytic property due to the 3-D interflow channels of MCF.
    • 摘要：為研究磷酸肌醇磷酸酶肌管相關蛋白14(MTMR14)在骨骼肌發生中的作用,通過組織切片和細胞培養技術研究了MTMR14敲除對骨骼肌的組織結構、成肌細胞分化和增殖的影響。結果表明：MTMR14敲除小鼠的腓腸肌和比目魚肌的結構較同窩野生型小鼠產生了明顯變化,MTMR14敲除小鼠的成肌細胞的分化和增殖成肌小管過程較野生型顯著加快。 MTMR14基因敲除后小鼠肌管細胞中平均細胞核數顯著增加。故MTMR14基因缺失/敲除導致骨骼肌組織結構異常,干擾了骨骼肌肌肉發生過程中的成肌細胞的增殖和分化。%To investigate the role of myotubularin related protein 14 (MTMR14), a novel phosphoinositide phosphatase, in regulating myogenesis, the effects of MTMR14 depletion on the structure, myoblast differentiation and proliferation were evaluated using tissue biopsy and cell culture techniques. The results demonstrated that the structures of both gastrocnemius and soleus muscles in MTMR14-depleted mice were different from their wild type ( WT) littermates. Compared to the WT control, the myoblast of MTMR14-depleted mice showed accelerated proliferation and differentiation into myotubes in culture. The depletion of MTMR14 also induced an increase of the number of nuclei in myotubes. In conclusion, the deficiency/depletion of MTMR14 led to the abnormal structure of skeletal muscles, and disrupted the proliferation and differentiation of myoblasts during skeletal myogenesis.
    • 摘要：采用ZnO：Ga3 O2高密度陶瓷靶作為濺射源材料,利用射頻磁控濺射技術在玻璃基片上制備了鎵鋅氧化物( GaZnO)半導體薄膜.基于X射線衍射儀的測試表征,研究了薄膜厚度對GaZnO樣品晶粒生長特性和微結構性能的影響.研究結果表明：所制備的GaZnO樣品為多晶薄膜,并且都具有六角纖鋅礦型結構和(002)晶向的擇優取向生長特性；其(002)取向程度、結晶性能和微結構參數等均與薄膜厚度密切相關.隨著薄膜厚度的增大,GaZnO樣品的(002)擇優取向程度和晶粒尺寸表現為先增大后減小,而位錯密度和晶格應變則表現為先減小后增大.當薄膜厚度為510 nm時,GaZnO樣品具有最大的(002)晶向織構系數(2.959)、最大的晶粒尺寸(97.8 nm)、最小的位錯密度(1.044×1014 m-2)和最小的晶格應變(5.887×10-4).%The gallium-zinc oxide ( GaZnO) semiconductor thin films were deposited on glass substrates by radio-frequency magnetron sputtering technique using the ceramic target fabricated by sintering the mixture of ZnO and Ga2 O3 nanometer powder. The influence of thickness on grain growth characteristics and microstructure of the deposited films was investigated by X-ray diffractometer. The results show that the deposited thin films with the hexagonal crystal structure are polycrystalline and have a strongly preferred orientation of (002) plane. The grain growth and mirostructure properties of the thin films are closely related to the thickness. As the thickness increases, the texture coefficient of ( 002 ) plane and grain size firstly increase and then decrease, while the dislocation density and lattice strain exhibit the reverse variation trend. The GaZnO thin film with the thickness of 510 nm possesses the best crystallite quality and microstructural properties, with the highest texture coefficient of (002) plane (2. 959), the largest grain size (97. 8 nm), the smallest dislocation density (1.044 ×1014 m-2) and the minimum lattice strain (5.887 ×10 -4).
    • 摘要：The continuous representation and reconstruction of discrete image are studied. Firstly, the continuous representation of image is given by string theory. Then, the fast algorithm of continuous image representation and reconstruction are implemented by Fourier transform. Next, the algorithm is applied to image zooming, image smoothing, edge detection and corner detection. Finally, the algorithm is compared with traditional discrete image processing method by some experiments. The results show that the effect of this method is not worse than the traditional discrete image processing method. The method makes it possible to process discrete image analytically.%研究了離散圖像的連續表示及重建問題。首先利用弦理論，給出了圖像的連續表示形式，然后利用付里葉變換實現了圖像連續表示及重建的快速算法，接著將它們應用于圖像無級縮放、圖像平滑、邊緣檢測、角點檢測，并與傳統離散圖像處理方法的實驗結果進行了比較。實驗結果表明：利用圖像連續表示方法處理離散圖像可以得到不差于傳統的離散圖像處理方法處理的結果，此方法使離散圖像的解析法處理成為可能。
    • 摘要：α-Bi2 O3/TiO2 composite nanoparticles were synthesized through a two-step hydrothermal method. Transmission electron microscopy ( TEM ) , X-ray photoelectron spectroscopy ( XPS ) , X-ray diffraction ( XRD ) and UV-vis diffuse reflection spectroscopy ( DRS ) were employed to clarify the structure and morphology of the nanoparticles. The photocatalytic activity of the composite was evaluated by using Rhodamine B ( RhB) as model contaminant. Compared with the single phaseα-Bi2 O3 or TiO2 , theα-Bi2 O3/TiO2 exhibited higher photocatalytic activity. The catalyst with 1︰5 molar ratio of α-Bi2 O3 and TiO2 showed the best photocatalytic activity:98. 5% RhB was degraded within 150 min under visible light irradiation. After three cycles, the catalyst still exhibited good photocatalytic activity.%采用兩步水熱法合成了α-Bi2 O3/TiO2納米粒子，利用透射電子顯微鏡( TEM )、X-射線光電子能譜儀(XPS)、X射線衍射儀(XRD)和紫外-可見固體漫反射光譜(DRS)對其進行了表征，以羅丹明B(RhB)為模型污染物評價了其光催化活性，結果表明：在模擬可見光源的照射下，α-Bi2 O3/TiO2比α-Bi2 O3、TiO2單體具有更好地光催化活性，當α-Bi2 O3與TiO2的摩爾比為1︰5時復合納米粒子的光催化活性最佳，光照150 min降解率為98.5%.經過3次循環利用，α-Bi2 O3/ TiO2納米粒子具有較好的穩定性.
    • 摘要：To investigate the variation of the chemical compositions and content of Diphylleia sinesis before and after processing, and uncover the processing mechanism of vinegar-stir-baked and vinegar-steamed method, the main chemical compositions in crude and processed Diphylleia sinesis were determined by UV,TLC and HPLC. The results indicated that the dissolution rate of the main chemical components in vinegar-stir-baked and vinegar-steamed product especially qucertin, kaempferol and podophyllotoxin significantly increased compared with crude product. After vinegar-steamed, a small amount of the podophyllotoxin converted into picropodophyllotoxin. This research provided theoretical and materials basis for formulating of quality control standard for the processing Diphylleia sinesis and the related research.%為研究“江邊一碗水”在炮制前后其化學成分和含量的變化規律，揭示醋炙法和醋蒸法的炮制機理。采用紫外光譜法、薄層色譜法和高效液相色譜法等檢測了“江邊一碗水”生品及其炮制品中的主要化學成分。結果表明：經炮制后，其醋炙品和醋蒸品中的主要化學成分的溶出率與生品相比均有不同程度的增加，其中槲皮素、鬼臼毒素、山奈酚等成分的含量增加顯著，且醋蒸后鬼臼毒素可少量轉化為苦鬼臼毒素。該研究可為“江邊一碗水“炮制質量控制標準的制訂及其相關研究提供一定的理論和物質基礎。
    • 摘要：To investigate ethnic medicines and their clinical applications in TMC hospitals in Xianfeng, Xuanen Counties and Lichuan City of western Hubei Province and facilitate the application standardization, the ethnic medicines ( decocting pieces) in the hospital pharmacies were investigated through sample collection, interview with ethnic physicians, collection and identification of the original plant specimens, sample identification and data compilation. The names, original plants, effectiveness and applications of the second batch of 19 Tujia medicines ( Miao medicine) in these hospitals were compiled. The problems in the literature and application about some medicines were corrected and the external characteristics of the crude drugs“laohumajing” and “huangjingtiao” were described for the first time. The study could serve as a reference for the standard application in hospitals and further research of the medicines of Tujia and Miao Nationality.%為考察鄂西土家族地區咸豐縣、宣恩縣和利川市中醫院民族藥及其臨床應用情況，規范品種的應用，對醫院藥房的民族藥材(飲片)品種進行了樣品收集、民族醫生訪談、野外對口原植物標本采集鑒定、藥材樣品鑒定和資料整理分析，現明確了第二批19個鄂西醫院用土家藥(苗藥)品種的名稱、基源、功效和應用，糾正了某些品種文獻記載和使用中的問題，首次對老虎麻莖、黃荊條藥材進行了性狀描述。研究結果可為促使土家族、苗族藥在醫院的規范使用和深入研究提供參考。
    • 摘要：目的：：了解民族高校婦女的圍絕經期癥狀及保健需求情況，為圍絕經期婦女保健工作提供科學依據.方法：采用問卷調查的方法，對民族高校647例40~60歲婦女進行調查.結果：調查對象圍絕經期相關癥狀發生率為77.13%，其主要癥狀依次為：記憶力下降(65.84%)、情緒波動(64.30%)、失眠(63.83%)、潮熱(58.73%)、月經紊亂(54.40%)等.各年齡組圍絕經期癥狀發生率比較，差異有統計學意義(p<0.05)，且隨著年齡增大，其發生率逐漸增高.圍絕經期婦女保健需求主要為定期全面體檢和預防骨質疏松；希望得到圍絕經期健康咨詢與指導的婦女占53.48%.結論：民族高校婦女圍絕經期相關癥狀發生率高，對圍絕經期保健知識及服務需求迫切.相關衛生服務部門應高度重視，實施干預模式，加強對民族高校圍絕經期婦女的健康管理，積極開展全科醫療衛生保健服務，以提高圍絕經期婦女的生活質量.%Objective:To understand the situation of perimenopausal symptoms and health care demand in nationalities university women, to community perimenopause women's health care and provide scientific basis for. Methods: Using the method of questionnaire survey was conducted on the 647 cases of 40 ~60 years old women in university . Results:The survey of menopausal symptoms, occurrence rate is 77. 13%, the incidence of main symptoms were:the decline of memory (65. 84%), mood swings (64. 30%), insomnia (63. 83%), fever (58. 73%), menstrual disorder (54. 40%). Each age group of perimenopausal symptoms occur rate compares difference to have statistical sense (p< 0. 05), increases with age, the incidence rate increase. Perimenopausal health care demand mainly for the regular physical examination and prevention of osteoporosis, hope to get the perimenopausal health counseling and guidance of perimenopausal women accounted for 53. 48%. Conclusion: the perimenopausal symptoms of University women associated with high incidence of perioperative care, knowledge and service demand of menopausal urgent. Community health service departments should attach great importance to, the implementation of community intervention model, strengthen the health management of University of perimenopausal women, actively carry out the general medical and health care services, in order to improve the quality of life of perimenopausal women.
    • 摘要：為了解決局部支持向量機算法KNNSVM存在的分類時間過長不利于具有海量數據量的高分辨率遙感圖像分類的不足，提高KNNSVM的算法表現，提出了改進的基于不確定性的BKNNSVM算法。該算法利用二項式分布的共軛先驗分布Beta分布根據近鄰的分布情況推導該未標記樣本屬于正類或負類的概率大小，從而計算每一個未標記樣本在類屬性上的不確定性大小。再通過設置不確定性閾值的大小，對不確定性低于閾值的未標記樣本直接采用KNN進行分類，而對高于閾值的樣本利用其近鄰建立局部支持向量機分類器進行分類。對高分辨率圖像分類的實驗結果表明：合適的閾值能夠有效降低原始KNNSVM算法的時間開銷，同時能保持KNNSVM分類精度高的特點。%In order to solve the deficiency about the algorithm of the local support vector machine ( KNNSVM ) which is very time-consuming on classifying the high resolution remote sensing images with mass data and improve the performance of the KNNSVM, the BKNNSVM algorithm based on uncertainty is proposed. The algorithm applies the binomial distribution of conjugate prior Beta distribution to estimate probability belong to the class or negative of each unlabeled sample through its nearest neighbor distribution. Then, with threshold, some unlabeled samples are classified by the KNN when their uncertainty value is less than threshold and others are classified by the local SVM when their uncertainty value is more than threshold. The experiments on the actual high resolution remote sensing images have shown that BNNSVM can decrease the time consuming effectively and keep the precision of the original KNNSVM with suitable threshold of uncertainty.
    • 摘要：針對諧波分析過程中常規窗函數存在精度不足的問題，提出了一種自乘法窗函數的構造方法，并以Hamming窗函數為例構造出1-9階乘法窗函數，將這些窗函數應用于四譜線插值諧波分析方法中，仿真實驗表明：構造出的自乘法窗函數相對于常規窗函數，在進行插值諧波分析中具有更高的準確度。工程實踐中可根據精度需要選擇所構造的窗函數階次。%In view of precision insufficient of the conventional window functions used in harmonic analysis, this paper introduced a construction method of self-multiplication window functions, and gave self-multiplication window functions of 1-9 orders based on Hamming window, and meanwhile verified a harmonic analysis method of four-spectrum-line-interpolation based on these multiplication window functions. The simulation experiments show that the constructed window function has a higher accuracy comparing to the conventional window function interpolation algorithm. In practical engineering, we can choose the constructed window function orders according to the needs of precision.
    • 摘要：以廣西某典型錳礦區中不同地域土壤為研究對象,研究了土壤中鉻(Cr)、鎘(Cd)、錳(Mn)3種重金屬的垂直分布規律和賦存形態.采用BCR三步連續提取法對土壤中3種重金屬進行形態分析以了解其潛在生態風險,采用原子吸收分光光度法分析了3種重金屬元素總量,通過地累積指數( Igeo )法對重金屬污染程度進行了評價.結果表明：土壤中Cr為輕度污染,Cd為嚴重污染,Mn的區域差異性較大,渣礦為清潔,酒店和礦場為偏重度污染.形態分析結果表明：Cr以殘留態為主,潛在生物有效性較低；Cd以酸可溶態、可還原態和可氧化態為主,潛在危害性較大；Mn在酒店和礦場以可還原態為主,而在渣礦以殘留態為主.3種重金屬不同深度的形態分布基本保持不變,重金屬污染無變化,但其本身污染嚴重,需采取相應措施進行土壤重金屬修復.%The vertical distribution and speciation of three heavy metals ( Cr, Cd ,Mn) were studied using the soil from the different regions in a typical manganese mine area in Guangxi Province. The potential ecological risks of these metals were analyzed from the speciation by using BCR three-step sequential extraction procedure. The distribution of heavy metals were analyzed by atomic absorption spectrometry. The heavy metal pollution was assessed by Geo-accumulation Index Method ( Igeo ) . The results showed that the manganese mine area were lightly polluted by Cr, heavily polluted by Cd. The pollution of Mn varied in different region, which was clean in the slag and a little heavy in hotel and mines. The speciation analysis suggested that most of the Cr existed in residual form and was of low potential biological effectiveness. Cd mainly existed in acid-soluble, reducible, and oxidizable form and was of greater potential harmfulness. Mn existed in reducible form in the hotel and manganese mine region, and existed in residual form in the slag. There were no significant changes in vertical distributions for the three metals. However, the area was seriously polluted, it was necessary to take effective measures to remedy the polluted soils.
    • 摘要：魚腥藻PCC7120染色體上的基因對asr0757/alr0758,經NCBI比對顯示其與大腸桿菌中的毒素-抗毒素基因MazEF具有較高的同源性,且具有毒素-抗毒素系統基因的保守遺傳結構,為研究其是否屬于MazEF家族系統基因,構建同時含有asr0757和alr0758基因的雙啟動子選擇性表達載體,先選擇性誘導了該基因對的表達,再驗證了其表達產物對細菌生長的影響.結果顯示：成功誘導表達出了目的蛋白asr0757(13.5KD)和alr0758(17.5KD),當單獨誘導asr0757基因表達時,細菌生長狀況不受影響,單獨誘導alr0758表達時細菌生長明顯受到抑制,同時誘導asr0757和alr0758基因時細菌生長恢復正常,說明asr0757/alr0758構成具有生物功能的MazEF家族系統基因對,具有毒性與抗毒性功能.%Anabaena sp. PCC7120 chromosomal genes asr0757/alr0758 were predicted to have high homology with the toxin-antitoxin genes MazEF in E. coli by comparing them on NCBI, and they both had the same conservative structure. To study whether they belonged to the MazEF family, selective expression vectors were built with double promoters, which contained both asr0757 and alr0758 genes. Then gene asr0757 and alr0758 were induced separately to verify the influence of the selective expression product on the growth of bacteria. The results showed that the target proteins asr0757(13. 5KD) and alr0758(17. 5KD) were successfully induced. The growth of bacteria was not affected when asr0757 gene was induced, whereas the growth was significantly suppressed when alr0758 gene was induced. The growth of bacteria reversed to normal, however, while asr0757 and alr0758 genes were induced at the same time. This result showed that asr0757 and alr0758 together constituted a gene pair of MazEF family which bequeathed the toxicity and anti-toxicity functions.
    • 摘要：Fibroin microspheres of degummed natural silk were successfully prepared by self-assembly method. The effect of stirring speed, amount of ethanol, concentration of fibroin and freezing temperature on the forming of the microcapsules were investigated. The results indicated that well shaped fibroin microspheres could be prepared with a stirring speed of 100 r/min, a V(EtOH)︰V(SF) ratio of 1︰20, w(SF) = 7. 0%, followed by freezing at –20℃ for 24 h, and finally melting at room temperature.%采用自組裝法以脫膠天然蠶絲為原料,制備了絲心蛋白微球.對影響微球的成球效果的因素如攪拌速度、乙醇(EtOH)用量、絲心蛋白(SF)濃度和冷凍溫度進行了初步探索.結果表明：當V(EtOH)/V(SF)=1︰20,w (SF)=7.0%時,以n=100 r/min的速度進行攪拌,再放入-20℃環境下冷凍24 h最后室溫融化,可獲得較理想的絲心蛋白微球.
    • 摘要：Objective:To study the effect of Long-man tea from Ampelopsis grossedentata on immunity functions of mice. Methods:The female Kunming mice were administered with Long-man tea from Ampelopsis grossedentata at the dose of 9. 10, 18. 20 and 54. 60 g·kg-1 once a day for 30 days by intragastric infusion, respectively. Then the weight, thymus, spleen , ConA-induced spleen lymphocyte proliferation, DNFB-induced DHT, the number of hemolytic plaque, half of hemolytic serum ( HC50 ) , carbon clearance ability, macrophage phagocytosis of chicken erythrocytes, NK cell activity were detected after one month with the tested samples. Results:Compared with control group, the dose of 18. 20 and 54. 60 g· kg-1 can strengthen the delayed type hypersensitivity of mice, strengthen NK cell activity and increase HC50 . The dose of 54. 60 g·kg-1 can increase the quantity of antibody forming cells. Each dose has no significant effect on body weight increase, ratio of spleen weight to body weight, ratio of thymus weight to body weight, and ability of mononuclear macrophage carbon clearance and chicken-red cells phagocytosis. Conclusion:Long-man Tea from Ampelopsis grossedentata can strengthen immunity functions of mice.%目的：：研究龍蔓藤茶增強免疫力功能的作用.方法：采用雌性昆明小鼠,設9.10、18.20、54.60 g·kg-13個劑量組,每日灌胃1次,連續給樣品30 d,檢測對小鼠體重、胸腺、脾臟器官、ConA誘導的脾淋巴細胞轉化、DNFB誘導的DTH、溶血空斑數、血清半數溶血值( HC50)、碳廓清能力、腹腔巨噬細胞吞噬雞紅細胞、NK細胞活性的影響.結果：與對照組比較,18.20、54.60 g·kg-1劑量能顯著提高小鼠遲發型變態反應能力、NK細胞活性、半數溶血值,54.60 g·kg-1劑量能顯著提高小鼠抗體生成細胞數,各劑量對小鼠體重增長、胸腺/體重比值、脾臟/體重比值、單核-巨噬細胞碳廓清能力及巨噬細胞吞噬雞紅細胞能力均無顯著影響.結論：龍蔓藤茶具有一定增強免疫力功能的作用.
    • 摘要：針對室內可見光通信應用場景,采用光線追蹤方法分析了無遮擋、半遮擋和全遮擋三種模型下信號傳輸特性,研究了接收機探測器視場角與三種模型下通信性能之間的對應關系.研究結果表明：探測器所處狀態由全遮擋模型切換至半遮擋模型時,平均接收信噪比僅降低1.51dB.切換至全遮擋狀態時,平均信噪比降至11.96dB,室內中心接收點仍能滿足通信基本要求.當視場角為50°時,可滿足室內不同遮擋模型切換時信號不中斷的通信需求.%Aiming at indoor visible light communication scenarios, the ray tracing method is used to analyze signal transmission characteristics of unobstructed、half blocked and full blocked model, and investigate the corresponding relationship between the field of view of the receiver concentrator and the performance of three models. The numerical results show that, when the state of detector switches from unobstructed model to half blocked model, the average received SNR only decreases 1. 51 dB. While the state switches to full blocked model, the average SNR reduces to 11. 96 dB, furthermore, the center receiving point of the room can still meet the basic requirements of communication. When the field of view is 50 ° , it can meet the requirements of continuous communication for hand over between different indoor blocked models.
    • 摘要：指出了動作識別中的最大困難是難以提取有效的特征來準確描述人體的動作，動作模板是眾多方法中的一種簡單有效的方法，用來描述動作特征的經典動作模板是運動歷史圖像。由于受噪聲的干擾，用運動歷史圖像描述復雜環境下的人體動作并不十分理想。為了得到比運動歷史圖像更加有效的動作模板，提出了將視頻序列中的運動能量信息用一張圖描述出來，稱之為累積運動能量圖像，提取其直方圖特征來表征人體動作。經YouTube數據集上的實驗表明：該累積運動能量圖像的識別率比同類方法高。%This paper points that very difficult to extract effective feature for describing the action of the human body in action recognition. Action template is a simple and effective method to describe the motion characteristics, in which motion history image is classic method. It isn′t satisfactory using motion history image to describe the human action in complex environment due to noise. In order to obtain more effective action template, this paper presents to use an image to describe motion energy in the video sequence, which is called accumulative motion energy image. The histograms extracted from the image are used to represent human action. Experiments on YouTube datasets show that accumulative motion energy image exceed to similar methods in recognition rate.
    • 摘要：This paper points out that through mining the society existed in complex networks, the topological structure and function of complex networks can be analyzed, and the hidden rules can be found either. In order to get the optimal community structure, node importance matrix and clustering matrix are defined, combined the spectral bisection method based on graph and modularity function, an community partition algorithm ( CDNIM ) based on node importance is proposed. This algorithm is applied in karate club, dolphin networks, and other classical data sets, the result of experiment shows that this algorithm can effectively improve the accuracy of discovering community structure.%指出了通過挖掘復雜網絡中存在的社團結構，可以分析整個復雜網絡的拓撲結構和功能，還可以發現網絡中隱藏的規律。為了得到最佳社團劃分結構，定義了網絡的節點重要度矩陣和聚類矩陣，結合圖的特征譜平分法和模塊度函數，提出了一種基于節點重要度的社團劃分算法( CDNIM)。通過在空手道俱樂部、海豚關系網絡等多個經典數據集上應用，結果表明：該算法能夠有效提高發現社團結構的準確率。
    • 摘要：Aiming at unrelated parallel machine scheduling problem, we introduced the idea of ant colony algorithm. Based on pheromone iterative model constructed by transfer probability, we researched the solving process of unrelated parallel machine scheduling problem. The results of the simulation test based on Python illustrate that ant colony algorithm can reach an approximate solution. Furthermore, we explored the influence of different task sequence on solution. At last, we performed some experiment to analyze time performance of the algorithm.%針對無聯系并行機調度求解問題，引入了蟻群算法的思想?；谵D移概率構建的信息素迭代模型，研究了無聯系并行機調度問題的求解過程?；赑ython的仿真實驗結果表明：通過蟻群算法可以得到其近似解；更進一步探求了任務次序對解的影響；通過實驗探索了此算法的時間性能。
    • 摘要：對于奇整數m≥5,構造了一類新的周期為2m -1的二元序列集,并完全確定了衡量新序列集性能的一個重要指標———相關分布。新序列集的最大相關值為2m+32+1,集合容量為22m +2m +1,和著名的Rothaus序列具有類似的相關性質,能適用于無線通信系統如CDMA通信系統。%For an odd integer m greater than 5, a new family of binary sequences of period 2m -1 is constructed. The correlation distribution, an important factor measuring the performances of this new sequence family, is determined completely. The new sequence family has maximum correlation 2m+32 +1, family size 22m +2m +1. It is identical to the well-known Rothaus sequences in terms of maximum correlation and family size. This sequence family is suitable for application in wireless communication systems such as CDMA system.
    • 摘要：In order to change the ligand type of the rare earth europium complexes and develop materials of better red light emission, three novel europium complexes were synthesized with Eu(Ⅲ) as the central atom, acetylacetone ( acac) as the first ligand, and three phenanthroline monoamine schiff base derivatives as the respective second ligand. The complexes were tested with UV and fluorescence spectra and their photophysical properties were also discussed. The results showed that the absorption in the UV region was enhanced gradually with the increase of the conjugation degree of the second ligand. The fluorescence emission peak was at about 613 nm attributed to the 5 D0→7 F2 characteristic transition of Eu3+. All three complexes emitted bright red fluorescence under UV exposure.%為改變稀土銪配合物的配體類型,尋找紅光強度更好的材料,以Eu(Ⅲ)為中心原子,乙酰丙酮( acac)為第一配體,3個鄰菲啰啉縮單胺類席夫堿衍生物作為第二配體,成功合成了3種新的銪金屬的配合物。測試了3種配合物的紫外、熒光光譜,探討了其光物理性能。結果表明：隨著第二配體結構共軛程度增加,在紫外區的吸收逐漸增強。其熒光發射峰均為約613 nm,歸屬為Eu3+的5 D0→7 F2能級間的躍遷,3種配合物在紫外燈下均發出明亮的紅光。
    • 摘要：采用循環伏安法在Q235鋼表面電化學合成了聚苯胺涂層,通過極化曲線評價了掃描方式、電位區間、掃描速率、循環次數等電聚合參數對聚苯胺涂層在Q235鋼耐腐蝕性能方面的影響,結果表明：合成條件對聚苯胺涂層的防護性能影響顯著.在0.1 mol/L苯胺+0.3 mol/L草酸溶液中,循環電位區間–0.5~1.6 V,掃速10 mV/s,連續掃描5個循環,可獲得最佳防護性能.該涂層在3.5% NaCl溶液中對Q235鋼具有較好的保護作用.掃描電鏡觀察表明：聚苯胺膜具有顆粒狀纖維狀結構.%Polyaniline ( PANI) coating was synthesized on Q235 steel by cyclic voltammetry ( CV) . The effect of electro-polymerization parameters ( scan method, potential range, scan rate and cycle number ) on anti-corrosion resistance of PANI for Q235 steel were studied from polarization curves. The results showed that synthetic conditions significantly affected the anti-corrosion resistance of PANI. The best protection performance could be obtained by CV between –0. 5 and 1. 6 V (SCE) with a scan rate of 10 mV/s for 5 cycles in a solution containing 0. 3 mol/L oxalic acid and 0. 1 mol/L aniline. The PANI coating demonstrated good protective performance in 3. 5% sodium chloride solutions. Scanning electron microscopy showed that PANI had granular and fibrous structure.
    • 摘要：為研究禽類多瘤病毒晚期基因多順反子翻譯起始調控的機制,設計和構建了以增強綠色熒光蛋白( EGFP)報告基因替代病毒APV-1野生型的晚期結構蛋白VPs基因的真核雙順反子表達載體,并觀察其在轉染進入禽類原代成纖維細胞中的表達翻譯狀態。以APV-1的cDNA克隆(pHL1003)為模板,運用PCR技術擴增出與野生型病毒APV-1相同的Ori區、早期編碼區和晚期Agno-1a區序列作為載體片段；從質粒pEGFP-N1中擴增出編碼綠色熒光的EGFP DNA片段；經連接構成重組質粒pHL1003-GFP,通過脂質體細胞轉染方法將質粒DNA轉染到雞胚胎和鵪鶉胚胎成纖維細胞中,通過細胞培養觀察熒光表達狀況。 DNA序列分析證實了重組克隆中的EGFP序列與已知的質粒pEGFP-N1中EGFP序列一致。轉染72 h后觀察雞和鵪鶉胚胎成纖維細胞,轉染成功胚胎細胞明顯表達較強的熒光,說明GFP可以在構建的雙順反子重組質粒的下游中正常表達并產生熒光。 pHL1003-GFP重組質粒的構建及其在禽類原代成纖維細胞中的高效表達,為我們研究多順反子翻譯起始調控中Agno-1a基因的表達對下游病毒結構蛋白基因的翻譯調控機制提供了簡潔易用的系統和模型。%To study the mechanism of translational initiation regulation of the polycistronic mRNA of the Avain Polyomavirus late genes, the eukaryotic expression vector with bi-cistronic mRNA was designed and constructed, in which the downstream late structural proteins of wild-type APV-1 were replaced by EGFP reporter gene. By transfection of the recombinant DNA into the bird primary fibroblast cells, the expression of EGFP was observed. Using APV-1 cDNA plasmid as template, the early and Ori regions including Agno-1a gene of the viral genome were amplified by PCR. The EGFP coding sequence was amplified from plasmid pEGFP-N1. After ligation of the above two kinds of DNA fragments, the recombinant plasmid pHL1003-GFP was identified by restriction enzyme digestions, PCR and DNA sequencing. The viral recombinant DNA was transfected into chicken embryo and quail embryo fibroblasts by lipofection respectively. The EGFP DNA sequence of the recombinant pHL1003-GFP was consistent with the EGFP sequence in the pEGFP-N1 plasmid by DNA sequencing analysis. After 72 h transfection , the GFP gene at downstream of the bi-cistronic mRNA was able to be expressed effectively, and the strong fluorescence of the GFP was excited in chicken embryo and quail embryo fibroblast cells. The construction of pHL1003-GFP recombinant plasmid and its highly expressed GFP with strong capability of fluorescence excitation in avian primary fibroblast cells provide a simple and easy testing system and an experimental model to explore the translational regulation mechanism in poly-cistronic mRNA of the Agno-1a gene for its downstream genes expression, which coding APV-1 late structural proteins.
    • 摘要：以Fe（NO3）3·9H2O為鐵源，乙二醇為溶劑和還原劑，采用溶劑熱法制備了Fe3O4磁性納米顆粒．利用XRD、FT-IR和TEM對其進行了物相和形貌的表征，以4-氯苯酚（4-CP）為目標污染物，評價了其活化H2 O2的性能．結果表明：制備的Fe3 O4納米顆粒近似呈球形，平均粒徑約15 nm，能夠有效地活化H2 O2產生· OH并高效降解4-CP．在25℃，Fe3 O4用量0．3 g· L-1，H2 O2濃度1．6 mmol· L－1，初始pH＝5．7時，所建立Fe3 O4-H2 O2氧化體系能在15 min內完全降解去除0．4 mmol· L－14-CP，較相同條件下超聲輔助反相共沉淀法制備的Fe3 O4效果更好．Fe3 O4活化H2 O2降解4-CP的機理主要是因為新的溶劑熱法可導致Fe3 O4磁性納米顆粒表面的富羥基化和配位作用．%Fe3O4 magnetic nanoparticles (MNPs) were prepared through a solvothermal method with Fe (NO3)3· 9H2O as precursor in the presence of ethylene glycol , which acted both as a solvent and reducing agent .The structure and shape of the Fe3O4 MNPs were characterized by XRD, FT-IR and TEM.The H2O2-activating ability of Fe3O4 MNPs was evaluated by using 4-clorophenol ( 4-CP ) as the target pollutant .The results indicated that the as-prepared spherical Fe 3 O4 MNPs were of diameter of about 15 nm, which showed strong catalytic ability toward the activation of H 2 O2 to produce hydroxyl radicals (·OH), causing efficient degradation of 4-CP.Under the test condition (Fe3O4 0.3 g· L-1, H2O2 1.6 mmol· L-1, initial pH 5.7, 25℃), 4-CP (0.4 mmol· L-1) can be efficiently degraded within 15 min under the established Fe3 O4-H2 O2 oxidation system , reflecting its superior performance than Fe 3 O4 MNPs prepared through ultrasound assisted reverse co-precipitation method.It was speculated that the mechanism of Fe 3 O4 MNPs activated H2 O2 for 4-CP degradation was attributed to the formation of abundant hydroxyl groups with strong coordination function on the surface of Fe 3 O4 MNPs.
    • 摘要：在厭氧-缺氧環境下，從磷礦廢水中篩選出一株高效的厭氧型聚磷菌，命名為AP06．對該菌株進行了生理生化研究及16 S rDNA序列分析，并對該菌株的聚磷效率和影響聚磷特性的因素進行了研究．結果顯示：菌株初步鑒定為Aeromonas sobria，聚磷效果最佳的pH值為7，溫度為30℃，磷源為KH2 PO4，接種量（ V／V）為7％，菌株的聚磷效率為86．1％．%A high-efficiency phosphate-accumulating bacterium strain named AP 06 was isolated from phosphorite wastewater .The strain was identified according to its physiological and biochemical characteristics , and its 16S rDNA sequence .The biological phosphorus removal characteristics of this strain were also studied .The results showed that the strain was identified as Aeromonas sobria.The phosphorus effect was best with removal rate of 86.1% when pH of the fermentation medium was 7, culture temperature was 30 ℃, KH2 PO4 was used as phosphorus source , and the inoculum concentration was 7%( V/V) .
    • 摘要：Metabolomics is a new omics technology which is developed after the genomics and proteomics , it aims at investigating the species and quantity of endogenous metabolites of organism , and the internal and external factors influencing metabolites of change regulation .Metabolomics is an important branch of the system biology , which is based on the analysis of group indicators , by means of high-throughput detection and data processing , and metabolomics takes the information modeling and system integration as target .In recent years , the value of metabonomics is expanding in various areas of pharmaceutical botany as large numbers of data and information accumulated . This review summarizes the generation, research methods and technology of metabolomics , and its application in medical plants , so as to provide a reference for relevant research .%指出了代謝組學是繼基因組學和蛋白組學之后新興的一門研究生物體內源代謝物的種類、數量及其在內外因素作用下變化規律的組學技術，是以組群指標分析為基礎，以高通量檢測和數據處理為手段，以信息建模與系統整合為目標的系統生物學的一個分支。近年來，隨著代謝組學積累的數據和信息量的增大，其在藥用植物學各個領域的應用價值也與日俱增。主要對代謝組學的產生、研究方法和技術及其在藥用植物研究中的應用進行了闡述，以期為相關研究提供參考。

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