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1.
为探究薄壳山核桃CiSULTR2.1基因功能及表达特征,以一年生薄壳山核桃实生苗为材料,利用RT-PCR和PCR技术克隆CiSULTR2.1基因全长,利用RT-qPCR技术分析其在不同浓度硒酸盐处理下的表达情况。结果表明,克隆得到1 902 bp的序列,经分析此序列属硫转运蛋白基因CiSULTR2.1全长开放阅读框的cDNA,编码633个氨基酸。CiSULTR2.1蛋白分子质量为68 943.37 Da,为疏水性的非分泌蛋白,无信号肽,结构稳定,二级结构主要由α-螺旋(51.18%)、延伸链(12.64%)和无规则卷曲(31.28%)构成,包含硫转运蛋白典型的Sulfate-transp结构域(PF00916)和STAS结构域(PF01740)。RT-qPCR分析结果表明,CiSULTR2.1在薄壳山核桃幼苗根与叶中均有表达,40、80 μmol·L-1硒酸盐处理下,12 h出现表达高峰,此后表达量明显下降;而0.5 μmol·L-1硒酸盐处理下,CiSULTR2.1表达高峰出现时间延后至48 h。硒酸盐浓度过高时,CiSULTR2.1表达量显著下降且低于对照。CiSULTR2.1基因能够快速响应40、80 μmol·L-1高浓度硒酸盐的诱导,而0.5 μmol·L-1低浓度硒酸盐需要较长时间才能诱导其高表达。高浓度硒酸盐处理较长时间对植物产生毒性效应,植物对硒酸盐的吸收减少,硒含量降低。本研究结果为薄壳山核桃CiSULTR2.1基因功能及硒吸收机制的研究提供了理论依据。  相似文献   

2.
美国山核桃总多酚与总黄酮含量及抗氧化活性   总被引:1,自引:0,他引:1  
为研究不同种质美国山核桃中总多酚与总黄酮含量及抗氧化活性的差异,对29个美国山核桃种质脱脂种仁的总多酚、总黄酮含量及抗氧化活性进行测定和比较。结果表明,29个美国山核桃种质脱脂种仁的总多酚、总黄酮含量及抗氧化活性存在显著差异,其中ZL86号种质总多酚含量最高,为47.96mg GAE·g~(-1),且抗氧化活性最强;ZL65号种质总黄酮含量最高,为24.01 mg RE·g~(-1);总多酚、总黄酮含量均与抗氧化活性呈极显著正相关。聚类分析将29个种质分为2类:Ⅰ类包含18个种质,其总多酚含量、总黄酮含量和抗氧化活性均较低;Ⅱ类包含11个种质,其总多酚含量、总黄酮含量和抗氧化活性均较高。本研究为美国山核桃品种的选育提供了一定的理论依据。  相似文献   

3.
On an edible portion basis, pecan moisture, protein, lipid, total soluble sugars, and ash contents ranged from 2.1% to 6.4%, 6.0% to 11.3%, 65.9% to 78.0%, 3.3% to 5.3%, and 1.2% to 1.8%, respectively. With the exception of a high tannin (2.7%) Texas seedling, pecan tannin content was in a narrow range (0.6-1.85%). Unsaturated fatty acids (>90%) dominated pecan lipid composition with oleic (52.52-74.09%) and linoleic (17.69-37.52%) acids as the predominant unsaturated fatty acids. Location significantly influenced pecan biochemical composition. Pecan lipid content was negatively correlated with protein (r = -0.663) and total sugar (r = -0.625). Among the samples tested using SDS-PAGE a common pattern, with minor differences, in subunit polypeptide profiles was revealed. Rabbit polyclonal antibody-based immunoblotting experiments (Western blot) also illustrated the similarity in polypeptide profiles with respect to immunoreactivity. All tested cultivars registered similar immunoreactivity when their protein extracts (each at 1 mg/mL) were assessed using inhibition ELISAs (mean +/- standard deviation = 0.89 +/- 0.20; n = 27) with the USDA "Desirable" cultivar as the reference standard (immunoreactivity designated as 1.0).  相似文献   

4.
Changes in composition during the maturation of Western Schley pecans [Carya illinoinensis(Wangenh.) K. Koch] grown in Australia were investigated. Pecans of different maturity levels were collected at monthly intervals between March and June in 1999 and 2000 and analyzed for the concentrations of moisture, total lipid, sucrose, raffinose, protein, and the minerals aluminum, boron, calcium, copper, iron, potassium, magnesium, manganese, sodium, phosphorus, sulfur, and zinc. Moisture, total lipid, and calcium contents changed significantly (p < 0.05) with harvest time and maturity, whereas the other components did not. Western Schley pecans grown in Australia should be harvested after the shuck has opened and it is either green or brown in color to maximize total lipid content and quality. This occurred after May 11 in 1999 and after May 17 in 2000.  相似文献   

5.
为了揭示周年施氮对复播大豆土壤有机质、养分和酶活性的后效及叠加效应的影响,并从中筛选出提高冬小麦-夏大豆轮作体系农田土壤肥力和周年产量的施氮组合。以冬小麦-夏大豆为研究对象,于2017~2019年采用裂区试验,前茬麦季设置4个施氮水平:0 kg·hm-2(N0)、104 kg·hm-2(N1)、173 kg·hm-2(N2)、242 kg·hm-2(N3);复播大豆设置3个施氮水平:0 kg·hm-2(S0)、69 kg·hm-2(S1)、138 kg·hm-2(S2),探究周年不同施氮组合对复播大豆土壤有机质、养分含量、土壤酶活性和周年产量变化规律的影响。结果表明:在大豆不施氮条件下,麦季施氮越多对大豆季土壤有机质、全氮、碱解氮、有效磷、速效钾含量以及土壤蔗糖酶和夏大豆产量的促进作用越明显。在麦季不施氮条件下,大豆季施氮越多越有利于增加土壤有机质、全氮含量以及土壤过氧化氢酶、脲酶活性和夏大豆产量,而土壤碱解氮、有效磷、速效钾含量和土壤蔗糖酶活性均随豆茬施氮量的增加呈先升后降的趋势,基本在豆茬N0S1施氮处理达到最大。在麦季各施氮基础上,与豆季S2施氮各组合处理基本能显著提高土壤全氮含量,而与豆季S1施氮的各组合处理基本有利于提高土壤有机质、碱解氮、有效磷、速效钾含量以及土壤酶活性和产量,且与豆季S0各组合处理基本呈显著差异。相关性分析表明,复播大豆产量与土壤有机质、全氮、碱解氮、速效钾及蔗糖酶活性均呈极显著正相关,与土壤脲酶呈显著正相关。因此,对于冬小麦-夏大豆轮作体系的施氮,要周年统筹安排,前茬麦季施氮量大,后茬相对要小,否则即使具有固氮能力的大豆也需要施一定的氮肥。在本试验条件下,麦季施氮水平为173 kg·hm-2时,大豆季再施69 kg·hm-2的周年氮肥组合,不仅有利于提高夏大豆土壤养分含量和酶活性,而且夏大豆产量和周年产量增产效果  相似文献   

6.
Pecans from the cultivars Wichita and Western Schley [Carya illinoinensis (Wangenh.) K. Koch] collected over three years were analyzed for the following constituents: total lipid content; fatty acid profiles; sucrose content; protein; total dietary fiber; the minerals magnesium, calcium, potassium, sulfur, phosphorus, boron, copper, iron, manganese, sodium, zinc, and aluminum; vitamin C; and lipase and lipoxygenase activities. Year of harvest and cultivar had little effect on the composition of the pecans. Overall, protein content was the only constituent that differed between pecans grown in Australia and those grown in the United States. This difference is probably related to differences in growing location and horticultural practices between the two countries.  相似文献   

7.
Pecans (cv. Desirable) contained approximately 10% protein on a dry weight basis. The minimum nitrogen solubility (5.9-7.5%) at 0.25-0.75 M trichloroacetic acid represented the nonprotein nitrogen. Among the solvents assessed for protein solubilization, 0.1 M NaOH was the most effective, while borate saline buffer (pH 8.45) was judged to be optimal for protein solubilization. The protein solubility was minimal in the pH range of 3-7 and significantly increased on either side of this pH range. Increasing the NaCl concentration from 0 to 4 M significantly improved ( approximately 8-fold increase) protein solubilization. Following Osborne protein fractionation, the alkali-soluble glutelin fraction (60.1%) accounted for a major portion of pecan proteins followed by globulin (31.5%), prolamin (3.4%), and albumin (1.5%), respectively. The majority of pecan polypeptides were in the molecular mass range of 12-66 kDa and in the pI range of 4.0-8.3. The pecan globulin fraction was characterized by the presence of several glycoprotein polypeptides. Lysine was the first limiting essential amino acid in the defatted flour, globulin, prolamin, and alkaline glutelin fractions. Leucine and tryptophan were the first limiting essential amino acids in albumin and acid glutelin fractions, respectively. Rabbit polyclonal antibodies detected a range of pecan polypeptides in the 12-60 kDa range, of which the globulin fraction contained the most reactive polypeptides.  相似文献   

8.
Rabbit polyclonal antibody-based inhibition ELISA as well as immunoblotting analyses of proteins extracted from variously processed pecans (cv. Desirable) indicate that pecan proteins are antigenically stable. Pecan antigens were more sensitive to moist heat than dry heat processing treatments. SDS-PAGE and immunoblotting analysis of the native and heat-denatured proteins that were previously subjected to in vitro simulated gastric fluid digestions indicate that stable antigenic peptides were produced. Both enzyme-to-substrate ratio and digestion time were influential in determining the stability of pecan polypeptides. The stable antigenic polypeptides may serve as useful markers in developing assays suitable for the detection of trace amounts of pecans in foods.  相似文献   

9.
氮钾肥配合施用对桑叶产量品质及蚕茧质量的影响   总被引:3,自引:0,他引:3  
通过连续4年田间施肥试验和一季养蚕试验,研究了氮肥和钾肥配合施用对桑叶产量、品质及相应桑叶喂饲家蚕对蚕生长及蚕茧品质的影响。结果表明,桑园施用氮钾肥显著提高桑叶产量,在氮钾肥各养分配比中,以高氮高钾处理(N450K300)的产量最高,比N0K0处理年均增产35.2%,与其他各处理产量差异显著。桑叶品质分析结果表明,桑叶中必需氨基酸、氨基酸总量、粗蛋白、油脂含量随氮肥用量增加而提高,但单施氮肥会对蛋氨酸和油脂含量产生负面影响;施钾导致糖分含量下降,其他品质参数值随钾肥施用而提高,氮钾肥配合施用具有提高桑叶品质的作用。养蚕结果表明,桑园增施氮钾肥生产出的桑叶,有助于降低蚕茧的死笼率、具有提高全茧量和茧层率及提高蚕茧产量的作用。蚕茧上茧率、茧丝长、解舒率和茧丝净度随着钾肥用量的增加而提高,在施钾基础上增加氮肥用量有提高蚕茧品质的作用,但不施钾只施氮肥对上茧率有负面影响,说明氮钾肥配合施用能促进蚕茧质量的提高。  相似文献   

10.
Abstract

Application of 11.2 kg B/ha and/or of 224 kg N/ha reduced the number of table beet (Beta vulgarisL. cv Detroit Dark Red) roots with B deficiency compared to low rates or no N or B application in three field experiments. In two of the three experiments, the 224 kg/ha N rate decreased B concentration in leaves when no B was added yet B deficiency of roots was reduced compared to the 56 kg/ha N rate. B application increased B concentration in leaves. Calcium concentration in leaves was higher at 224 kg N/ha than for 56 kg N/ha. Nitrogen concentration in leaves was increased by increasing the rate of N while K concentration was decreased at the higher N rate. Average number of roots with B deficiency was significantly higher for the Morse strain than for the Harris strain of ‘Detroit Dark Red’ in one experiment where the two strains were compared. There were no differences between the two strains in leaf B concentration but Ca concentration was higher in the Morse strain than for the Harris strain. Yields were higher at the 224 kg/ha rate of N than at 56 kg N/ha but were not consistently affected by B and K applications. There was no clear relationship of leaf N, Ca and K concentrations to B deficiency of roots  相似文献   

11.
施钾对不同肥力土壤玉米钾素吸收、分配及产量的影响   总被引:5,自引:0,他引:5  
采用田间试验, 研究了吉林省高(榆树市)、低肥力(公主岭市)肥力条件下不同钾肥用量对玉米产量、钾素吸收和分配的影响。结果表明, 榆树试验点和公主岭试验点的最高产量施钾量分别为83.3 kg·hm-2和113.9 kg·hm-2, 最佳经济施钾量分别为75.1 kg·hm-2和103.1 kg·hm-2。公主岭低肥力试验点比榆树高肥力试验点的最高产量和最佳经济产量分别提高了3.70%和3.68%。施用钾肥可有效提高玉米干物质最大积累速率和钾素最大吸收速率, 并能提前干物质最大积累速率和钾素最大吸收速率出现的天数。当施钾量超过60 kg(K2O)·hm-2时, 公主岭低肥力试验点的干物质最大积累速率和钾素最大吸收速率均高于榆树高肥力试验点。适宜的钾肥用量有利于提高钾养分由营养体向籽粒的转运量、转运效率及籽粒养分比例, 榆树高肥力试验点籽粒养分比例低于公主岭低肥力试验点, 幅度为0.5%~1.7%。除施钾量60 kg(K2O)·hm-2处理外, 公主岭低肥力试验点的钾肥农学利用率、偏生产力和利用效率等指标均高于榆树高肥力试验点, 分别提高7.3~8.8 kg·kg-1、4.4~8.3 kg·kg-1、1.6%~6.2%。综合考虑提高玉米产量、效益及钾肥利用效率, 高肥力土壤适宜施钾量为75 kg·hm-2, 低肥力土壤上适宜施钾量为103 kg·hm-2。  相似文献   

12.
对不同土壤肥力水平下元白菜施氮、磷、钾和锌肥的效应研究表明,不同土壤肥力水平下,元白菜施氮、磷、钾和锌均能显著增加产量,分别增产12.0%~35.8%(平均24.5%)、5.3%~14.1%(平均9.7%)、11.2%~15.3%(平均12.9%)和7.5%~11.3%(平均9.1%)。在较高、中等和较低土壤肥力水平下,元白菜经济最佳施氮(N)量分别为310.5、326.1~336.6和378.9 kg/hm2,适宜磷(P2O5)用量依次为60、60~90和90~120 kg/hm2。不同土壤肥力水平地块元白菜适宜施氮时,氮肥(N)利用率在15%~20%,适宜施磷时磷肥(P2O5)利用率在9.3%~11.0%;元白菜上钾肥利用率随土壤钾素水平的降低而呈增加的趋势,不同土壤肥力地块元白菜施K2O 120 kg/hm2时钾肥(K2O)利用率平均为20.4%。  相似文献   

13.
不同土壤肥力水平下元白菜施氮、磷、钾和锌的效应   总被引:2,自引:0,他引:2  
对不同土壤肥力水平下元白菜施氮、磷、钾和锌肥的效应研究表明,不同土壤肥力水平下,元白菜施氮、磷、钾和锌均能显著增加产量,分别增产12.0%~35.8%(平均24.5%)、5.3%-14.1%(平均9.7%)、11.2%.15.3%(平均12.9%)和7.5%~11.3%(平均9.1%)。在较高、中等和较低土壤肥力水平下,元白菜经济最佳施氮(N)量分别为310.5、326.1~336.6和378.9kg/hm^2,适宜磷(P2O5)用量依次为60、60-90和90~120kg/hm^2。不同土壤肥力水平地块元白菜适宜施氮时,氮肥(N)利用率在15%~20%,适宜施磷时磷肥(P2O5)利用率在9.3%~11.0%;元白菜上钾肥利用率随土壤钾素水平的降低而呈增加的趋势,不同土壤肥力地块元白菜施K2O120kg/hm^2时钾肥(K2O)利用率平均为20.4%。  相似文献   

14.
红壤稻田不同施肥制度对土壤钾平衡和水稻产量的影响   总被引:4,自引:1,他引:4  
基于14年田间定位试验,研究了红壤稻田系统在不同化肥配施条件下,有机养分循环利用对土壤K素平衡和水稻产量的影响。结果表明:不施肥或仅施化肥,土壤K素严重亏缺,其中以不施K的NP处理最严重,平均每年亏损K120.1kg/hm2,有机物养分循环利用的施肥制度可大幅度降低稻田土壤K素的亏损甚至出现K素盈余,NP C处理平均每年亏损K素2.2kg/hm2,而NPK C处理平均每年盈余K素154.5kg/hm2,但过高的K输入可能导致K营养元素的大量流失,降低K肥资源利用效益并增加环境污染风险,实行有机物养分循环利用时应适当减少化肥K的施用量;在不同施肥基础上的有机物养分循环利用都能显著提高水稻产量,但“循环”增产率随化肥配施程度提高而降低,不施肥基础上有机物养分循环利用的稻谷增产率为56%,与NP配施后,有机物养分循环利用的增产率降至18.8%,而在NPK配施基础上有机物养分循环利用的增产率只有10.2%,处理NPK C2与处理NPK之间的稻谷产量却没有显著差异,可见有机养分循环利用可以代替化肥K的施用;有机养分循环利用降低了K内部利用效率(IKUE)值,大小顺序为NPK C相似文献   

15.
施钾对不同基因型棉花光合特性及产量和品质的影响   总被引:7,自引:3,他引:7  
在田间条件下,研究了施钾对抗虫杂交棉中棉所38、抗虫棉新棉33B、常规棉中棉所12光合特性和产量及品质的影响。结果表明,与不施钾相比,不同基因型棉花施氯化钾225.kg/hm2,棉花叶面积指数(LAI),叶绿素荧光动力学参数PSⅡ最大光化学量子效率(Fv/Fm)、PSⅡ潜在光化学活性(Fv/Fo)、PSⅡ实际光化学效率(ФPSⅡ),叶片净光合速率(Pn)、气孔导度(Gs),棉花干物重及分配到生殖器官的比例,棉花总成铃数、铃重和衣分均有不同程度提高;中棉所38、新棉33B和中棉所12皮棉产量分别增加13.60%、10.66%和4.21%;棉纤维2.5%跨距长度、比强度、马克隆值和纤维整齐度等品质也得到改善。中棉所38和新棉33B比中棉所12施钾的效果更好,生产上应优先给抗虫杂交棉和抗虫棉品种施用钾肥。  相似文献   

16.
以“欧美罗”紫甘蓝为试材,通过田间试验,探究不同水肥耦合条件下紫甘蓝功能叶片氮代谢相关酶活性及产量差异。对照组(CK)为当地传统水肥管理(N 466.5 kg/hm2,P2O5 756 kg/hm2,K2O 269.91 kg/hm2,大水漫灌和撒施);处理组采用双因素交互设计,因素一为不同灌水下限,设3个梯度:W1(田间最大持水量的80%)、W2(田间最大持水量的60%)、W3(田间最大持水量的40%);因素二为施肥量,设3个施肥梯度:F1(当地传统施肥量)、F2(80%当地传统施肥量)、F3(60%当地传统施肥量)。与CK相比,处理组W2F2紫甘蓝叶片叶绿素含量、氮代谢相关酶活性、可溶性蛋白含量、干物质积累量及产量均显著增大且达到最高值。在相同灌水量条件下,硝酸还原酶(NR)、谷氨酸脱氢酶(GDH)、谷氨酸合成酶(GOGAT)、谷氨酰胺合成酶(GS)活性,以及可溶性蛋白含量、干物质积累量、叶绿素积累量和产量均随着施肥量的减少呈现先升高后降低的趋势;在相同施肥量条件下,紫甘蓝叶片NR、GDH、GOGAT、GS活性、可溶性蛋白含量、叶绿素含量和产量均在灌水下限为60%时达到峰值。W2F2(田间持水量60%,N、P、K分别为373.2、604.8、215.93 kg/hm2)  相似文献   

17.
氮、磷、钾对湿害胁迫下甘蓝型油菜产量的影响   总被引:2,自引:0,他引:2  
对甘蓝型油菜品种中双10号和中油杂5号苗期进行水淹处理模拟湿害胁迫,运用“3414”肥料效应田间试验方案,研究湿害胁迫下施肥量对油菜产量的影响。结果看出,施氮磷钾肥对湿害胁迫下的油菜产量性状有重要影响。灰色关联分析表明,施氮量与每角粒数、单株角果数和一次分枝数、二次分枝数和主花序长呈显著正相关;施磷量与单株角果数和每角粒数呈显著正相关;施钾量与每角粒数、千粒重和主花序长有呈显著正相关的趋势。湿害胁迫下,保证中等水平的磷肥和钾肥,增施氮肥可显著提高油菜的单产、投产比和经济效益。通过建立肥效与产量间的效应函数方程,在湿害危害严重的油菜种植地区,适宜肥料用量为:N 267 kg/hm2、P2O5 120 kg/hm2、K2O 120 kg/hm2。  相似文献   

18.
马铃薯覆膜方式对土壤氮磷钾养分与产量的影响   总被引:5,自引:1,他引:5       下载免费PDF全文
针对宁夏南部山区马铃薯覆膜种植的特殊环境,通过田间试验研究了不同覆膜方式下土壤氮磷钾养分及马铃薯产量变化特征。结果表明,与露地种植相比较,随着马铃薯生育期的延长,全膜覆盖种植表层(0~20 cm)土壤有机质和有效磷具有累积现象,半膜种植表层(0~20 cm)土壤全氮和碱解氮含量较高,但对下层(20~60 cm)土壤有机质、全氮、碱解氮和有效磷含量影响较小,无论是马铃薯全膜种植还是半膜种植均对土壤速效钾含量影响较小,甚至略有降低,其中半膜种植降低最为显著,降幅达47.3 mg/kg。与露地相比较,覆膜种植可显著增加马铃薯产量,其中马铃薯全膜种植单位面积产量最高,达50 609 kg/hm~2,而马铃薯半膜种植由于受后期降雨的影响,烂薯较多,对产量造成较大影响。因此,马铃薯在生长后期降雨充沛的情况下可考虑揭膜管理措施。  相似文献   

19.
生殖生长阶段甜瓜坐果节位叶片早衰现象严重,不利于养分、光合同化产物向果实转移,导致产量和品质下降。试验研究了不同氮钾肥用量对大棚甜瓜坐果节位叶片生理特性的影响,延缓坐果节位叶片衰老,以期为优质高产栽培条件下合理施肥提供一定的理论依据。试验设重氮重钾(N2K2)、重氮轻钾(N2K1)、轻氮重钾(N1K2)、轻氮轻钾(N1K1)、中氮中钾(NK)5个处理。结果表明,不同氮钾处理对甜瓜超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性和可溶性蛋白质(SP)、丙二醛(MDA)含量影响显著,随着氮钾肥用量的增加,SOD、POD、CAT活性和SP含量均呈先增加后下降的趋势,MDA含量的变化趋势则相反,呈先降低后上升;合理的氮钾肥用量(NK处理)有利于减缓SOD、POD、CAT活性和SP含量的降低速度和MDA含量的增加速度,越到生育后期效果越明显,高氮高钾(N2K2)处理反而不利于减缓SP含量和SOD、POD、CAT活性的降低速度及MDA含量的增加速度,加剧叶片衰老。NK处理甜瓜产量、中心和边部可溶性固形物含量及植株氮、磷、钾累积吸收量均显著高于其它处理,但氮钾肥用量过高或过低均不利于植株对氮、磷、钾素的吸收,影响其产量和品质的提高。通过综合分析不同氮钾肥用量对甜瓜生理特性及产量、品质、养分吸收累积量的影响,确定在连栋棚加地膜覆盖高产栽培条件下,土壤施氮、钾量分别以N 200 kg·hm-2、K2O 300kg·hm-2为宜,但施氮、钾量过高或过低均加速甜瓜生殖生长阶段叶片抗氧化保护酶活性及渗透调节物质的降解速度,加剧叶片衰老,从而不利于产量和品质的提高。  相似文献   

20.
不同有机肥配比对蔬菜产量和品质及土壤肥力的影响   总被引:19,自引:0,他引:19  
试验选择了5种有机肥料,采用6种配比在生菜和青花菜上进行了试验。研究表明,鸡粪、猪粪、牛粪按1∶1∶3或按1∶1∶1配比,青花菜的产量显著高于鸡粪、猪粪、牛粪、草炭为1∶1∶1∶1的配比。鸡粪、猪粪、牛粪按1∶3∶1的配比能明显提高青花菜的Vc和可溶性糖含量。鸡粪、猪粪、牛粪、草炭、玉米秸秆按1∶1∶1∶1配比能明显提高青花菜的粗蛋白和Vc含量。  相似文献   

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