Comment on "Detecting awareness in the vegetative state"

Owen et al. (Brevia, 8 September 2006, p. 1402) claimed that a patient's brain activity revealed that she was consciously responding to commands despite being in a vegetative state. However, several alternative explanations were not eliminated. Specifically, the activity could reflect unconscious reactions to the last word in the command, not conscious decisions to respond. A refined experimental design could clarify these issues.     

Preserved feedforward but impaired top-down processes in the vegetative state

Frontoparietal cortex is involved in the explicit processing (awareness) of stimuli. Frontoparietal activation has also been found in studies of subliminal stimulus processing. We hypothesized that an impairment of top-down processes, involved in recurrent neuronal message-passing and the generation of long-latency electrophysiological responses, might provide a more reliable correlate of consciousness in severely brain-damaged patients, than frontoparietal responses. We measured effective connectivity during a mismatch negativity paradigm and found that the only significant difference between patients in a vegetative state and controls was an impairment of backward connectivity from frontal to temporal cortices. This result emphasizes the importance of top-down projections in recurrent processing that involve high-order associative cortices for conscious perception.     

Comment on "Preserved feedforward but impaired top-down processes in the vegetative state"

Boly et al. (Reports, 13 May 2011, p. 858) investigated cortical connectivity patterns in patients suffering from a disorder of consciousness, using electroencephalography in an auditory oddball paradigm. We point to several inconsistencies in their data, including a failure to replicate the classical mismatch negativity. Data quality, source reconstruction, and statistics would need to be improved to support their conclusions.     

四川苏铁(Cycas szechuanensis)营养器官的解剖结构研究

对四川苏铁(Cycas szechuanensis Cheng et L.K Fu)根、茎、叶的解剖结构进行了研究.结果表明,根初生结构由表皮、皮层和中柱3部分组成,未见明显的中柱鞘和内皮层,具二原型木质部,皮层薄壁细胞中含有大量的晶体;茎具大量薄壁组织,薄壁组织中有明显的分泌腔,薄壁细胞富含淀粉粒,维管束呈环形排列或散布在薄壁组织中;叶柄的基本组织中具有裂生分泌腔,5～8束维管束呈弧形排列或散布在薄壁组织中;羽片叶上表皮的角质层厚,气孔分布在下表皮,有小叶脉产生.根、茎、叶木质部中的管胞主要是螺纹和孔纹管胞,有少量纤维.     

云南大叶种茶的无性繁殖

云南是世界茶树的原产地，其独特的地缘优势蕴育了丰富的茶树品种资源。云南大叶种茶就生长于这样得天独厚的自然环境中，以其外形满被茸毫，色泽鲜绿，香气持久，滋味醇厚而享誉海内外。以云南大叶种茶制成的名优绿茶从古至今，久盛不衰。尤其是以无性系良种制成的名优绿茶，倍受青睐。云南大叶种茶无性系良种的高产优势、清香的特性，越来越受广大茶农欢迎，倍受……     

尖孢镰刀菌致病菌营养体亲和群研究

在分离、鉴定侵染黄瓜的尖孢镰刀菌的基础上，测定30个尖孢镰刀菌菌株（包括6个专化型）对黄瓜的致病性和营养体亲和性。研究结果表明，侵染我国黄瓜的尖孢镰刀菌至少有5个以上的营养体亲和群（VCGs)，除来自黑龙江的9909－1菌株与膜的黄瓜根茎腐专化型（Fusarium axysporum f.sp.radicis-cucmeinun,FOCS)菌株属同一亲和群外，其它菌株均与希腊的尖孢镰刀菌黄瓜专化型（F.o.f.sp.cucumerinum,FOC)和FORC不亲和，本文所测定的尖孢镰刀非致病菌株均与致闰 株不亲和，不同专化型的尖孢镰刀菌菌株归属于不同的营养体亲和群。研究结果初步显示了应用营养体亲和性区分菌的致病性及专化型的可能性。     

牛至草营养器官的解剖学研究

采用常规石蜡切片法对牛至草的营养器官进行了解剖学研究。结果表明:牛至草根的初生木质部为2原型,次生结构中次生木质部导管发达,中央有髓;茎具备了典型的双子叶植物茎的初生结构,由表皮、厚角组织、皮层、初生韧皮部、维管形成层、初生木质部、髓细胞组成;叶为典型的两面叶,气孔分布在叶下表皮。     

仙客来营养器官的解剖学研究

仙客来营养器官的解剖试验表明 ,仙客来种子萌发后 ,主根早期停滞发育 ,由下胚轴膨大具有茎结构特征的块茎 ,随着发育产生异常结构 ,致使块茎不断长大。在块茎下端产生不定根 ,构成须根系 ,每条根均由表皮、皮层、中柱三部组成。在块茎上端可产生一至数个不定芽形成短缩茎。其上丛生叶与花。解剖学研究表明 ,块茎、短缩茎和花柄均为茎的结构 ,叶片肥厚、健壮 ,由发达的栅栏组织和海绵组织组成的异面叶     

蚕豆营养生长期缺钾形态诊断初报

以蚕豆品种8074为材料,在严重缺钾土壤条件下,研究蚕豆营养生长期的缺钾症状。结果表明,土壤速效钾含量为25.2mg·kg-1时,蚕豆叶片先是尖端及边缘,继而叶片前、中部出现红褐色斑点或斑块,斑点(块)颜色逐渐加深,呈现症状的叶片部分萎蔫,蚕豆的营养生长严重受阻,植株矮小,根系分支少,根瘤少,单株分枝数与正常植株相近。     

两个优质菜用大豆品种的评价

对 6 0份国内外引进的大豆种质可否作为菜用大豆品种直接栽培利用进行了试种评价。结果表明 ,来自日本的两个品种表现优良 :一个为早熟品种 ,定名为苏引 1号 ,蛋白质含量 4 6 % ,该品种 4月初至 7月上旬播种 ,6月上旬开始采收毛豆 ;一个为晚熟品种 ,定名为苏引 2号 ,蛋白质含量 4 2 % ,4月初至 6月初播种 ,7月上旬采收毛豆。两品种具备了抗病虫、适宜播期宽、籽粒大、易蒸煮、口味佳等特点 ,可作为毛豆品种直接栽培利用     

基于跨文化的英语教学中文化意识渗透

语言文化是人类社会孕育出的产物,其代表着一方文化,也是人们开展交流的重要工具。因此当我们国家的人需要对其他国家进行了解时,语言就是一种能够帮助其进行深入理解的工具。跨文化是学习不同语言过程中会产生的文化差异问题,也是当前外语语言教学的重点所在。文章以跨文化为主,首先分析了在英语教学中融入跨文化内容的现实意义,后分析了当前跨文化教学中存在的培养问题,最终对基于跨文化的英语教学文化意识渗透路径进行了深入的研究分析。     

华东地区半夏属群体营养器官的比较解剖及其演化

对华东地区半夏属内５个种７个群体进行营养器官的比较解剖,结果发现：（１）半夏属有３种类型的气孔器;有晶簇和针晶两种类型的晶体,晶簇为原始性状;导管直径的进化趋势由小到大。这３种性状十分稳定,可用来判断类群的进化程度并作为半夏属药材组织鉴定的依据。（２）半夏是具有明显多态现象的复合种,性状的变异幅度很大,但很容易通过无融合生殖将基因型保存下来。（３）盾叶半夏、鹞落坪半夏较为原始,虎掌、半夏较为进化。（４）半夏可能由鹞落坪半夏进化而来。     

悬铃木贮藏蛋白的初步研究

以不同季节悬铃木的枝条为研究对象,利用光学显微技术和SDS-PAGE技术研究枝条中贮藏蛋白在生长期和休眠期的分布情况。经汞-溴酚蓝染色后的石蜡切片显微观察表明,休眠期枝条细胞中存在大量蓝色蛋白颗粒,在生长期枝条细胞中则未发现这种蛋白颗粒的明显存在。SDS-PAGE结果表明,休眠期枝条中的有2条分子量分别为31 ku和45 ku的蛋白大量特异表达。     

Characterizing the limits of human visual awareness

Momentary awareness of a visual scene is very limited; however, this limitation has not been formally characterized. We test the hypothesis that awareness reflects a surprisingly impoverished data structure called a labeled Boolean map, defined as a linkage of just one feature value per dimension (for example, the color is green and the motion is rightward) with a spatial pattern. Features compete with each other, whereas multiple locations form a spatial pattern and thus do not compete. Perception of the colors of two objects was significantly improved by successive compared with simultaneous presentation, whereas perception of their locations was not. Moreover, advance information about which objects are relevant aided perception of colors much more than perception of locations. Both results support the Boolean map hypothesis.     

Rheologic characteristics of cryolabile vegetative raw materials

Rheologic characteristics of cryolabile subtropical fruits (kiwi, feijoa, ebony) after freezing, cryoprotector processing, and processing with low frequencies have been defined. The efficiency of using these processes in subtropical cryolabile materials has been demonstrated.     

Motion integration and postdiction in visual awareness

In the flash-lag illusion, a flash and a moving object in the same location appear to be offset. A series of psychophysical experiments yields data inconsistent with two previously proposed explanations: motion extrapolation (a predictive model) and latency difference (an online model). We propose an alternative in which visual awareness is neither predictive nor online but is postdictive, so that the percept attributed to the time of the flash is a function of events that happen in the approximately 80 milliseconds after the flash. The results here show how interpolation of the past is the only framework of the three models that provides a unified explanation for the flash-lag phenomenon.