Odor cues during slow-wave sleep prompt declarative memory consolidation

Sleep facilitates memory consolidation. A widely held model assumes that this is because newly encoded memories undergo covert reactivation during sleep. We cued new memories in humans during sleep by presenting an odor that had been presented as context during prior learning, and so showed that reactivation indeed causes memory consolidation during sleep. Re-exposure to the odor during slow-wave sleep (SWS) improved the retention of hippocampus-dependent declarative memories but not of hippocampus-independent procedural memories. Odor re-exposure was ineffective during rapid eye movement sleep or wakefulness or when the odor had been omitted during prior learning. Concurring with these findings, functional magnetic resonance imaging revealed significant hippocampal activation in response to odor re-exposure during SWS.     

梅花鹿鹿茸生长及骨化与碱性磷酸酶的关系

选用５头雄性梅花鹿、测定鹿茸生长速度,相对骨质密度,血清碱性磷酸酶活力,结果表明,在整个鹿茸生长期内,鹿茸生长速度,相对骨质密度,ＡＫＰ活力均有显著变化,在生长期骨化程度低且增长缓慢,而生长速度显著加快。在骨化期,骨化程度较高且迅速增加,生长速度迅速下降,骨化完成时停止生长;ＡＫＰ活力在生长期与生长速度同步升高,在骨化期下降。锯掉单侧茸后,ＡＫＰ活力明显下降。     

传统中式香肠自然晾挂成熟过程中生理生化特性及微生物的变化

对传统中式香肠自然晾挂成熟过程中的理化特性、生化特性和微生物的变化规律进行了测定和分析。结果表明,传统中式香肠自然晾挂成熟过程中的水分活度和水分均在干燥前16 d迅速下降,然后缓慢降低;pH则在干燥前12 d迅速下降,然后缓慢降低;蛋白质、脂肪和滴定酸度均在干燥前12 d迅速升高,然后缓慢上升;N aC l含量在整个干燥过程中一直显著上升;总糖虽然也一直呈上升趋势,但是不明显;色度在干燥前8 d迅速上升,然后快速下降;除非蛋白氮外,酸价、过氧化值、羰基价、硫代巴比妥酸值、氨基酸态氮、挥发性盐基氮均在整个干燥过程中呈上升趋势;好氧菌总数、厌氧菌总数、嗜冷菌总数、酵母和霉菌总数均在干燥前12 d呈上升趋势,然后迅速下降;乳酸菌总数在干燥前8 d呈上升趋势,然后迅速下降。     

不同刈割时期对紫花苜蓿干草调制的影响

对不同刈割时期的紫花苜蓿干草品质的研究表明：盛花期刈割的苜蓿干燥速度快于初花期和结荚期,晾晒28h以上即可成功调制优质干草,初花期和结荚期刈割的苜蓿成功调制干草需要晾晒32h;调制干草的适宜含水量是20％左右;初花期苜蓿叶的蛋白质含量是茎的2．41-2．95倍,苜蓿干草的叶量是决定苜蓿品质的主要因素;不同刈割时期调制的苜蓿干草茎叶比差异较大,结荚期明显高于盛花期和初花期,是初花期的5-7倍。在初花期刈割,调制干草中茎叶比变化较小,叶损失少,可获得高质量的干草。     

金针菇生长发育期间相关胞外酶的活性变化研究

以白色金针菇菌株为材料,研究其生长发育过程中羧甲基纤维素酶、半纤维素酶、漆酶、酸性磷酸酶和中性蛋白酶活性的变化规律.结果表明,整个生长发育期间胞外酶活性变化具有明显的阶段性.羧甲基纤维素酶菌丝营养生长阶段活性较低,现蕾后活性急剧增强,达到11.43U;半纤维素酶高峰出现于采收期,达到8.13U;漆酶在菌丝营养生长阶段活性较高,原基形成后迅速下降到0.15U;中性蛋白酶菌丝营养生长阶段活性比较稳定,现蕾前相对较低,子实体生长阶段酶活性明显增强;酸性磷酸酶活性随着菌丝培养呈下降趋势,但生殖生长期迅速升高.     

不同基因型烤烟质体色素降解及与烤后烟叶挥发性降解物含量关系

【目的】研究不同基因型烤烟成熟和调制过程中色素降解及与烤后烟叶中性挥发性色素降解成分含量的关系。【方法】采用液相色谱方法测定豫中浓香型烟区9个不同基因型烤烟中部叶质体色素含量。【结果】在成熟和调制过程中烟叶的质体色素含量呈下降趋势,叶绿素的总降解量总体大于类胡萝卜素,且叶绿素a的降解量显著大于叶绿素b,在调制后烟叶中叶绿素b残留量较多,叶绿素在烟叶成熟期的降解量大于在调制期间的降解量。在类胡萝卜素中叶黄素含量和降解量最大,且在成熟期间的降解量大于调制期间的降解量,新黄质在成熟期的降解量大于调制期间的降解量,但β-胡萝卜素和紫黄质在调制期间的降解量大于成熟期间的降解量。不同基因型色素降解量不同,且与调制后烟叶色素降解类中性香气成分含量多呈显著正相关关系,与调制后烟叶色素含量无显著相关性或呈负相关关系。类胡萝卜素降解产物总量和许多重要香气成分与成熟期色素降解量的相关性大于与调制期降解量的相关性。【结论】烟叶成熟过程中叶绿素、叶黄素和新黄质的降解量大于调制期的降解量。烤后烟叶中挥发性色素降解香气成分含量与质体色素的降解量,特别是成熟期色素降解量有密切关系,提高烟叶成熟度对促进烟叶香气物质形成至关重要。     

秋茬生菜深水栽培氧的需求规律

以意大利耐抽薹生菜为试验材料,研究了深水栽培条件下不同生长发育阶段营养液中的溶氧量和单株吸氧量的变化。结果表明,生菜的不同生长阶段营养液中溶存氧的日变化和植株单株吸氧量有所不同,生长初期,氧需求量和吸收量均较少,只需补充少量的氧就可满足正常生长的需要;生长中期氧的需求和吸收量均较高,生长末期氧需求量减弱,吸收量也明显下降。生产管理上应注意增加和补充生长中期的充氧时间和充氧量,适当减少生长末期的充氧量。     

小麦返白系叶片核酸含量及核酸酶活性研究

测定了小麦返白系和对照矮变 1号的全卷叶、半卷叶和初展叶中核酸含量及核酸酶活性在返白过程的变化。结果表明 ,在返白过程中返白系各叶龄叶片 DNA和 RNA含量均不程度地降低 ,复绿时又迅速增高 ,其 DNA水解酶 ( DNase)和 RNA水解酶 ( RNase)活性变化趋势与之相反 ,且叶片愈幼嫩变化幅度愈显著 ;分析显示 ,核酸含量的降低与核酸水解酶活性的升高有关 ,也与返白过程叶绿体结构破坏有关     

Cholinergic enhancement and increased selectivity of perceptual processing during working memory

Using functional magnetic resonance imaging, we investigated the mechanism by which cholinergic enhancement improves working memory. We studied the effect of the cholinesterase inhibitor physostigmine on subcomponents of this complex function. Cholinergic enhancement increased the selectivity of neural responses in extrastriate cortices during visual working memory, particularly during encoding. It also increased the participation of ventral extrastriate cortex during memory maintenance and decreased the participation of anterior prefrontal cortex. These results indicate that cholinergic enhancement improves memory performance by augmenting the selectivity of perceptual processing during encoding, thereby simplifying processing demands during memory maintenance and reducing the need for prefrontal participation.     

试论汉俑造像艺术

汉代艺术在继承了先秦艺术思想的同时,受到中西文化交流和南北文化融合影响,又多了一层人的自信精神。作为汉代雕塑的一种艺术形式,汉俑是这个时期造像艺术的典型代表。受到祖先崇拜思想影响和周汉礼教的约束,汉俑造像在历史与现实、神与人的纷繁交融中,体现着汉民族自信浪漫、自由活泼及简洁雄浑的性格,极富魄力的汉俑造像,见证了汉代艺术的辉煌,并散发出两汉艺术大气而浪漫的精神。     

四川省单季稻高低温致灾因子危险性分析

开展单季稻高低温致灾因子危险性分析,可为四川省单季稻生产防灾减灾提供理论支持.基于1981年-2012年四川省26个气象台站单季稻观测资料和逐日气象资料,利用水稻高、低温灾害指标,从灾害发生频率、次数和强度等方面定量分析了四川省单季稻生育期内高温和低温致灾因子的危险性.结果表明:1981年-2012年四川省单季稻秧田期低温和灌浆结实期高温的发生频率较高,大部地区超过60%;秧田期低温和灌浆结实期高温的发生次数较多,大部地区在26~50次;秧田期低温和灌浆结实期高温的发生强度较高,大部地区分别为4~12天/次和6~9天/次.近30年来,四川省单季稻秧田期的低温发生次数和强度呈减少趋势;开花期高温发生次数基本不变,发生强度呈现降低趋势;灌浆结实期高温发生次数和强度呈增加趋势.四川省不同区域和不同生育阶段单季稻高温和低温致灾因子的危险性存在差异,需要因地制宜地应对气象灾害带来的不利影响,保障单季稻的安全生产.     

小鼠乳腺发育、泌乳和退化的组织形态学(Ⅱ)——超微组织形态学变化和β-酪蛋白分泌

研究小鼠乳腺发育、泌乳和退化的超微组织形态学以及蛋白质分泌功能变化,为产奶动物泌乳生物学与乳腺功能调控奠定实验基础;将小鼠青春期、妊娠期、泌乳期和退化期乳腺,一部分制成超薄切片复染法染色后在透射电镜下进行超微结构观察,另一部分制成冰冻切片应用免疫组织化学染色方法进行β-酪蛋白分泌跟踪。结果为透射电镜观察见青春期(性成熟前期和退化期)或静止阶段乳腺上皮细胞胞质内含细胞器相对较少,泌乳期上皮细胞变成高柱状或立方形,胞质内内质网丰富,近腺腔处见大量分泌颗粒,泌乳期乳腺肌上皮细胞内可见少量分泌小泡;β-酪蛋白跟踪染色发现,β-酪蛋白在妊娠初期就有表迭,到泌乳期达到相对稳定水平;小鼠青春期、妊娠期、泌乳期和退化期乳腺结构呈现有规律的周期性变化。     

UV-B辐射强度变化对冬小麦碳氮代谢的影响

采用室内盆栽实验的方法,研究了UV-B辐射强度改变对冬小麦拔节孕穗期、抽穗期碳氮代谢的影响.结果表明：（1）UV-B辐射增强显著减少小麦拔节孕穗期和抽穗期地上部分干重,以及小麦拔节孕穗期地上部分呼吸速率,而对小麦两个生育期的呼吸系数无显著影响.UV-B增强显著减少了小麦拔节孕穗期和抽穗期叶片中叶绿素a含量,增加类胡萝卜素含量,减少拔节孕穗期叶片中光合产物可溶性糖的含量;（2）UV-B增强对小麦叶片中N代谢过程的影响表现为促进作用,虽对小麦抽穗期叶片硝酸还原酶活性、硝态氮含量无显著影响,却促进谷氨酰胺合成酶活性,显著增加了拔节孕穗期和抽穗期叶片中可溶性蛋白质、游离氨基酸含量.     

我国传统腊肉在腌制过程中品质的分析监测

[目的]研究我国传统腊肉在腌制过程中品质的变化.[方法]基于传统加工工艺,监测并分析腊肉腌制过程中的水分、脂肪过氧化值、蛋白质的消化性和亚硝酸盐含量等的变化情况.[结果]试验显示,在腊肉的传统制作过程中,其水分含量在烟熏过程中减少最多;脂肪酸价和过氧化值总体呈现上升趋势,在晾干过程中上升趋势更加明显;腊肉中挥发性盐基氮的含量在晾干过程中呈现逐渐增加的趋势;亚硝酸盐含量在腌制和熏制过程中均未有明显变化,在晾干过程中稍有提高,但是变化不大,不影响腊肉的营养和卫生.[结论]研究可为腊肉的腌制加工提供一定的参考依据.     

拟南芥Ran小GTP结合蛋白在细胞有丝分裂中的定位

分别采用RT-PCR和直接荧光免疫方法分析Ran2 mRNA在拟南芥不同组织器官中的表达及Ran2的亚细胞定位。结果表明,Ran2基因在拟南芥根、茎、叶和花中均有表达;Ran2蛋白在细胞分裂间期主要定位于核膜周边,在后期定位于赤道板上和纺锤体上,末期又回到子细胞核膜周边。     

Song replay during sleep and computational rules for sensorimotor vocal learning

Songbirds learn a correspondence between vocal-motor output and auditory feedback during development. For neurons in a motor cortex analog of adult zebra finches, we show that the timing and structure of activity elicited by the playback of song during sleep matches activity during daytime singing. The motor activity leads syllables, and the matching sensory response depends on a sequence of typically up to three of the preceding syllables. Thus, sensorimotor correspondence is reflected in temporally precise activity patterns of single neurons that use long sensory memories to predict syllable sequences. Additionally, "spontaneous" activity of these neurons during sleep matches their sensorimotor activity, a form of song "replay." These data suggest a model whereby sensorimotor correspondences are stored during singing but do not modify behavior, and off-line comparison (e.g., during sleep) of rehearsed motor output and predicted sensory feedback is used to adaptively shape motor output.     

黄连木雌花芽形态分化期叶片氮、磷、钾含量变化研究

为揭示黄连木(Pistacia chinensis Bunge)雌花芽形态分化期的营养特性,对黄连木雌花芽形态分化各时期叶片内氮、磷、钾含量变化进行了研究.结果表明:在黄连木雌花芽形态分化过程中花芽节位叶片中氮、磷、钾含量均为花芽分化始期含量最高,分别为18.28,3.87,17.78 g/kg,此后,在花芽分化过程...     

Seasonal Variation of Major Elements in South Lake Cyohoha,Rwanda

The paper analyzed the seasonal variation of the concentrations of Cr,Mn,Al,N,P,As,Ba,Ca,Cu,Fe,Mg,and K in South Lake Cyohoha water using spectroscopic technique.Water samples were taken monthly at Ngenda,Karehe and Nyamabuye stations from January 2009 to December 2010.The results showed that the concentrations of aluminum,nitrogen,potassium,arsenic,phosphorous,manganese,chromium,barium and copper were high during the raining season and low during the dry season,while calcium,iron and magnesium varied independently with seasonal change.The results of conductivity and pH also confirmed the effects of seasonal change on the quality of water in the South Lake Cyohoha since the highest value of conductivity was found during the raining season,while the smallest was observed during the dry season,for pH the highest number was noticed during the dry season and the lowest during the raining season.     

不同抗性玉米自交系感蚜期四种酶活性变化分析

本试验对网棚隔离和大田种植条件下3种玉米自交系感蚜期叶片和雄穗内PPO、POD、PAL、ASA-POD活性变化进行了测定分析。结果表明,自然感蚜后3种感性材料PPO、POD活性在不同时期的叶片和雄穗内都明显增高;PAL活性在不同时期的叶片和衰落期、消亡期的雄穗内有所升高;ASA-POD活性在不同时期雄穗内有所增高。3种感性材料隔离状态和自然感蚜状态下＂9401＂叶片PPO活性在衰落期和消亡期最低,PAL活性在盛蚜期和衰落期均最低,表现为随抗性降低而降低;＂9401＂雄穗POD活性在衰落期和盛蚜期最高,ASA-POD活性在盛蚜期最高,表现为随抗性降低而增高。     

Early Morphological and Physiological Events Occurring During Germination of Maize Seeds

The early morphological and physiological events occurring during maize （Zea mays cv. Nongda 108） seed imbibition and germination were studied. Water uptake of seeds exhibited a triphasic pattern with a marked increase during the initial phase of imbibition, and then a slow increase, followed by a second substantial increase. Imbibition time for 10 and 50% of seed germination was about 26 and 46 h at 30℃, respectively. The relative conductivity of maize seeds dramatically decreased during the initial phase of imbibition, followed by a substantial increase. Respiratory rate of seeds gradually increased with imbibition. Length of root cap cells decreased during the initial phase and then increased; those of meristematic zone cells increased during the initial phase and then decreased; and those of elongation zone cells and of the whole elongation zone of the radicle gradually increased during germination. The contents of soluble sugars and starch in embryos gradually decreased as the activities of α- and β-amylase strikingly increased with imbibition. In the meantime, protein contents of embryos gradually decreased and free amino acid content increased. The activities of aminopeptidase and endopeptidase increased until 12 h of imbibition and then decreased. It is concluded that germination of maize seeds is mainly completed by extension of cells in the elongation zone of the radicle, and that mobilization of stored reserves in the embryo during the initial phase of imbibition is also an early event during seed germination.