益母草的染色体数目

Leonurus japonicus Houtt. [L. heterophyllus Sweet, L. artemisia  (Lour.) S.  Y. Hu]  is one of the most important traditional Chinese medicines used as a remedy for gynaeco- logical disease since ancient times.  A cytological investigation on the species was carried out and the materials for chromosomal examination were collected from 26 localities in 20 provi- noes and autonomous regions of this country.  The number of chromosomes in root tip cell of the species was found to be 20 on the whole (Tab. 1:1), agreeing with those reported by Ma and al.[2] and probably by Chuang and al.[3] as well.      The genus Leonurus L. is variable in its  chromosomes with an aneuploidy of x=9, 10 and 12.  The present authors would propose that the primitive basic number of chromosome in the genus is 9, and thus both 10 and 12 are derived, for: (1) among the 9 species (including 1 sub- species) heretofore cytologically examined, x=9 occurring in 66.7%, x=10 occurring in 22.2%, while x=12 occurring only in 11.1%; (2) in generaclosely related to the genus under considera- tion, such as Panzeria, Galeobdolon and Lamium x=9 being the sole basic number.      But L. japonicus exhibits a mixoploidy of 2n=20 (occurring at the rate of 53.30% of the total amount of cells examined), 2n=18 (30.70%), and 2n=16 (15.99%) in our work. (Table 1).  Since the original basic number of  chromosome of the genus is 9 as proposed above, 2n= 20 would be considered as a derived one and the occurrence of 2n=18 probably suggests an early evolutionary trend of 2n=18→20 of the pecies in question.     

利用△R(n)/△n界定核心区域的探讨

Based on R (n) - n curve, this article makes a deep analysis of △R (n) /△n from the mathematical,geometrical and actual meanings. The change of △R (n) /△n indicates that there is a clear convergence and dispersion inthe actual distribution of the documents of the journals. The area in which △R (n) /△n changes greatly is the core area,the area in which △R (n) /△n changes continuously is the dispersive area, and the point at which the variance of △R (n) /△n is bigger than 1 for the two adjacent journals may be taken as the boundary line between the core area and the non-core area.     

蜘蛛抱蛋属(百合科)的细胞分类学研究(1)——四川七个种的核型

In the work mitotic chromosomes in root-tips of 7 species native to Sichuan Pro- vince were examined and their karyotypes were analysed based on 7-8 cells at mitotic meta- phase, using Levan et al.'s (1964) nomenclature. The list of species and origin of the materials used in this work are provided in the appendix.  The micrographs of mitotic metaphase of all the materials are shown in Plates 1 and 2; the idiograms in Fig. 1, 1-9, and the parameters of chromosomes are provided in Tables 1-9.  All the chromosome countings and karyotypes in this paper are reported for the first time.      Characteristics of the karyotypes may be summarized as follows:      1.  2n=38 are found in all the materials except A. sichuanensis, which has 3 cytotypes, i.e, 2n=38+5B, 2n=38+lB and 2n=38+OB (Plate 2, 1-2, Fig. 1, 5-6).      2.  The karyotypes are of two major types: the karyotype of A. flaviflora falls into 3C in Stebbins's (1958, 197l) classification of karyotypes and those of all the other species into 2C. The two types are also different from each other in the number of large and medium-sized chromosomes pairs and morphology of the first pair of chromosomes (compare Plate 2, 5, Fig. 1, 9 with the other micrographs and idiograms).A. flaviflora with the karyotype 3C also differs from the other species in a series of gross morphological characters: the species is of a yellow and campanulate corolla.      3.  The species with caespitose leaves (A. caespitosa and A. omeiensis) have essentially the same karyotype, which is rather different from those of the species with scattered leaves. There are two pairs of small sm chromosomes (arm ratio ≥1.90) in the former karyotype (Tables 1 and 3), but all the small chromosomes are m or sm with arm ratio <1.80 in the latter karyotypes.     

An Analysis of the Function and Status of CAS in National Nanotechnology Research

NB I C, n a m e l y n a n o sc i e n ce &nano-technology, biotechnology & bio-medicine (including genetic engineering),information technology (including computing andcommunications) and cognitive science (includingcognitive neuroscience) are universally regarded asfour R&D disciplines to critically influence humanlife in the near future. Providing technological ground-work for the latter three’s healthy development,nanoscience and related technologies now becomethe most active S&T frontiers…     

Neopolarographic Study On Vitamin D

Vitamin D_2 and vitamin D_3 give a clear polarographic oxidation-wave,respectively,by neopolarography,with a 0.25M solution oflithium perehlorate in ethanol-dimethylformamide(1:1)as the supportingelectrolyte.Peak potentials are both+1.27V(vs.pure Ag plate).Thewave-height is proportional to the concentration in the range from 2.6×10~(-6)M(1μg/ml)to 1.1×10~(-3)M(420μg/ml)for vitamin D_3 and from2.5×10~(-6)M(1μg/ml)to 1.1×10~(-3)M(435μg/ml)for vitamin D_2,respe-ctively.The detection limits are both 1.3×10~(-6)M(0.5μg/ml).Themethod can be satisfactorily applied to the determination of vitamin D_3in injcction.Through various experiments,it is shown that the electrodeprocess of vitamin D at glassy carbon electrode is an irreversible oxida-tion process controlled by diffusion.The value of an is 0.84(α is thetransfer coefficient and n is the number of cleclron in the kineticprocess).n=2.The electrode reaction mechanism has been inferred.Besides,the choices of base solution and of experiment conditions aswell as the stability of vitamin D etc.are also discussed.     

超声波

使我们的耳朵感觉到声音的声波,是一种能够在空气、水和固体中传播的弹性波。声源的振动,使得同它紧挨着的一部分媒质,受到了周朝性的挤压;这一部分媒质又按照振动本身的周期性的变化过程,把挤压力传递给最邻近的一层媒质;这样,轮流交替的波密和波疏,就传遍了媒质所占据的全部空间(图1)。每一声波都具有一个说明自己的特性的物理量,这就是在一秒钟以内波密和波疏流交替的次数,这个量就叫做频率。频率不同的声音,我们听起来就有高低的差异。最低的声音,如鼓和大     

超声波在固体中传播和散射的研究

超声波在固体中的散射问题,是超声学科中的一个基本问题;也是超声一些应用领域中的基础问题.在媒质中,超声一经产生,即向前传播.在多数情况下,媒质可以被看作是均匀的,但不能是无限的.由此,超声的传播终将遇到媒质的边界;另一种可能是,在均匀媒质的内部,有局部的不均匀区,此时超声在到达媒质的边界之前,先撞上了这个区.超声碰上了媒质     

National Center for Nanoscience and Nanotechnology Holds Board Meeting

The governing board of the Nationa l Cen ter for N a n o s c i e n c e a n dNanotechnology of China(NCNNC) held a meeting onMarch 1 in Beijing. The meeting was presided overby Board Chairman and CASPresident Lu Yongxiang and at-tendedbyhigh-rankingofficialsandboard members from the Ministryof Science and Technology, theMinistryof Education,the NationalNatural Science Foundation ofChina, Beijing MunicipalGovernment, Peking University,Tsinghua University and C…     

中国特有的露蕊乌头亚属及铁破锣的染色体研究

The paper reports chromosomal number and chromosomal morphologies of annual Aconitum gymnandrum endemic to China and Beesia calthifolia for the first time.  Of the two spcies, chromosome number is same (X=8, 2n=16) and chromosome average lengths are 6.17μ , 10.73μ respectively.  The longest chromosome 1, the short chromosomes 3-5, 7 and the shortest chromosome 8 are metacentrical (m), the chro- mosomes 2, 6 are submetacentrical (sm), and the pairs 4, 5, 8 have satellites in the karyotype of A. gymnandrum.  In B. calthifolia, all of the chromosome 1-5 are the long m, the chromosomes 6, 8 are the short sm and the 7 is telocentrical (t). The pairs 3, 4, 6 have satellites.      According to the comparison of karyotypes of three subgenera—subgen. Para- conitum, subgen. Aconitum and subgen. Gymnaconitum in Aconitum, the evolution trend of chromosomes is further discussed.      Finally, the relationship between Aconitum and Beesia is also discussed in thispaper.     

On the Continuity of the Matrix PadéOperator

Let [m/n]_f be the matrix Padé approximant (MPA, left-or righthanded) for a given matrix-valued power series f. Let T_(m,n)~n, be the operator which maps f to [m/n]_f. It is well known that in the scalar. case T_(m,n)~n satisfies a (local) Lipschitz condition if and only if [m/n]_f has a zero defect. However, in the matrix case we are confronted with the difficulty that we cannot give a definition of defect.In this paper, an explicit expression of MPA is given and a result about the continuity of the matrix Padé operator is obtained.     

知母染色体核型的研究

  A karyotypical analysis of Anemarrhena asphodeloides Bung. of the monotypic genus Anemarrhena Bung. (Liliaceae) was carried out for the first time. The number of chromo- somes in root-tip cell of the species was found to be 22, agreeing with that reported by Sato[12], although inconsistent in some other respects, such as position of  centromeres, length of chromosomes, and nucleoli, etc. (Table 1 ). According to the terminology defined by Levan et al.［8］, the karyotype formula is therefore 2n=22=2sm (SAT)+2sm+18m. Photomicrographs of the chromosome complements and idiogram of the karyotype are given   Fig. 1 and 2).       The karyotype of Anemarrhena asphodeloides shows explicitly to be asymmetrical, with three pairs of long chromosomes and eight pairs of short chromosomes. This specialized feature, when considered together with the rare occurrence of the basic chromosome number of 11 of the genus within the Tribe Asphodeleae of Liliaceae (see Table 1), suggests that the genus Anemarrhena is probably a rather specialized one, which has scarcely any intimate relationship with the other genera of the above tribe. The fact that this specialized karyotype is associated with certain trends of morphological specialization, such as flowers possessing three stamens only, gives support to the above suggestion. But, it is impossible to draw a more precise conclusion without a more thorough and comprehensive investigation of the species in question.     

Steady-state burning plasma: a new stage in the development of magnetic confinement fusion energy

<正>In the last century, the fusion triple product n TτE (density, ion temperature and energy confinement time) obtained on tokamak devices have increased faster than the ‘Moore’s law’ in the field of chips.However, after the JET, TFTR and JT-60 U three large devices, the international joint construction of the International Thermonuclear Experimental Reactor(ITER) began. No larger device has been built yet,     

四川及其邻近地区一些植物的细胞学研究(一)

From standpoint of floristic division,  Sichuan is located in the middle part of Eastern Asiatic Region (Takhtajan 1978) or is the area where Sino-Himalayan Forest Subkingdom and Sino-Japan Forest Subkingdom meet (wu 1979).  Here exist many so- called Arcto-Tertiary elements and newly originated species or races.  In order to bring the light the origin and differentiation of Eastern Asiatic elements,  cytological investi- gation on plants of this region are very significant.  The materials of the following 5 species were collected on Mt.  Emei in Sichuan Province.  Voucher specimens are kept in CDBI.       1.  Toricellia angulata  Oliver var. intermedia (Harms) Hu       PMC meiotic examination revealed n = 12 at diakinesis (Pl. I fig. 9)       Toricellia,  consisting of 2 spp.,  is endemic to Eastern Asiatic Region.  Based on our result along with the report of Toricellia tiliifolia (Wall.) DC. (2n=24) by Kuro- sawa (1977),  we argue that the basic chromosome number of Toricellia is 12.  Many authors,  such as Airy-Shaw (1973),  Dahlgren (1975,  1977),  Takhtajan (1969,  1980), Thorne (1983),  have adopted Hu’s (1934) treatment erecting it as a monotypic family Toricelliaceae.  Its systematic position,  whether closer to Cornaceae than to Araliaceae or vice versa,  has been in dispute.  Cytologically it seems closer to Araliaceae,  as shown anatomically (Lodriguez 1971),  because the basic chromosome number of Cornaceae s. 1. is x=11,  9,  8 (Kurosawa 1977),  whereas that of Araliaceae is 12 (Raven 1975).       2.  Cardiocrinum giganteum  (Wall.) Makino       Somatic chromosome number,  2n=24 was determined from root-tip cells (Ph. I. fig. 8).       Cardiocrinum (Endl.) Lindl.,  consisting of 3 spp.,  is endemic to Eastern Asiatic Region.  C. giganteum (Wall.) Makino is distributed from Himalayan region to S. W. China.  The present report is in accord with the number reported by Kurosawa (1966) who got the material from Darjeeling of India.  However the karyotype of the present plant is slightly different from that given by Kurosawa.  In the present material,  the satellites of the 1st. pair of chromosomes and the short arms of llst.  pair of chromoso- mes are visibly longer than those of Kurosawa’s drawing (fig. 1,  2) The plants from Yunnan,  Sichuan and Hubei Provinces,  named as C. giganteum var. yunnanense (Leit- chtlin ex Elwes) Stearn,  differ slightly from those of Himalayan region also in outer morphological characters.  The taxon needs both cytological and taxonomical further studies.       3.  Disporum cantoniense  (Lour.) Merr.       PMC meiotic examination revealed n=8 at diakinesis (Pl. I. fig. 6)       This species is widely distributed from Himalayan region through Indo-China to our Taiwan Province and Indonesia. Three cytotypes (2n=14,  16,  30) were reported for the taxon including its variety,  var. parviflorum (Wall) Hara,  by various authors (Ha- segawa 1932,  Mehra and Pathamia 1960,  Kurosawa 1966,  1971 Mehra and Sachdeva 1976a).  Some authors consider D. pullum Salisb. and D. calcaratum D. Don as synonyms of D. cantoniense. So D. cantoniense may be a species aggregate with different extreme races.  Sen (1973a,  b.) reports that the somatic chromosome numbers of D. pullum and D. calcaratum from Eastern Himalayan region are 14,  16,  28,  30,  32.  He also discovered that chromosome alterations in species of Disporum involve not only the num- ber but the structure as well.  He found that in species of Liliaceae where the reproduc- tion is mainly vegetative,  polysomaty often occurs.  In China we have not only D. can- toniense and D. calcaratum but also D. brachystomon Wang et Tang which is similar to D. cantoniense var. parviflorum (Wall.) Hara.  These taxa need further critical studies.      4.  Paris fargesii Franch.      PMC meiotic examination revealed n=5+2B (Voucher no. 112) or n=5 (Voucher no. 62) at MI and AI (Pl. I. fig. 1. 4. 5.).  This is the first report for the species.  A bridge and a fragment were also observed at AI.      Paris polyphylla Smith is extraordinarily polymorphic species.  Hara (1969) re- gards all chinese extreme forms,  such as P. fargesii Franch.,  P. violacea Lévl.,  P. pube- scens (Hand. -Mzt.) Wang et Tang,  etc. as infraspecific taxa of P. polyphylla.  Need- less to say,  the various races of P. polyphylla Smith in China need further critical stu- dies and are good material for further study to understand the speciation.      5.  Reineckia carnea(Andr.) Kunth       Reineckia is a monotypic genus endemic to Eastern Asiatic Region.  In the present material somatic chromosome number in root-tip cells is determined as 2n=38 (Pl. I. fig. 7).  According to the terminology defined by Levan et al.,  the karyotype formula is 2n=28 m+10 sm.  The length of chromosomes varies from 14.28 μ to 5.5 μ. The idiogram given here (fig. 3) is nearly the same as that presented by Hsu et Li (1984). The same number has been previously reported by several authors,  Noguchi (1936),  Satô (1942), Therman (1956).  The karyotype is relatively symmetrical (2B,  accorling to the classi-fication of stebbins 1971) in accord with the opinion of Therman (1956).     

声速测量实验原理分析

声速测量是根据入射波和反射波叠加后的状态随反射界面到声源的距离的不同而呈现出周期性的变化这一特点进行测量的,由于实际的情况比理想的情况复杂的多,使得波在界面上的反射理论常常容易出现错误的观点。为此,在忽略媒质对声波吸收的情况下,推出两波叠加后的方程,并使学生更清楚的认识到示波器显示的波形是声压波不是位移波。     

中药抚芎的原植物及其与川芎、藁本的比较

The  vegetative  characters of  Ligusticum  chuanxiong  Hort.  cv.  Fuxiong are described in comparison with L. chuanxiong Hort. and L. sinense Oliv. The chromosome numbers and karyotypes of the three taxa were studied in root tip cells by Feulgen’s squash method. Their karyotypes are determined as follows: L. chuanxiong, K(2n)=22=16 m+ 4sm+2st (sat); L. chuanxiong cv. Fuxiong, K(2n)=33=24 m+6sm+3st (sat); L. sinen- se, K(2n)=22=12 m+6sm+2sm (sat)+2st (sat).      The karyotypic similarities are found between L. chuanxiong and its cultivariety, butthe former is a diploid while the latter probably is a homologous triploid.     

The ancient Book of Changes inspires policies for modern Chinese scientific research

正1 Introduction The output of scientific research in China ranks second in the world according to the Nature Index of 2015(www.nature.com/nature/journal/v522/n7556_supp/full/522S34a.html)and the ISI Web of Science(http://thomsonreuters.com).Although important advances have been made,it should be noted that China has the largest     

Strive for S&T Innovations under the Guidance of the Scientific Outlook on Development

China’s S&T community must, with a high sense of m i s s i o n a n d responsibility, strive to put into practice the scientific outlook to- ward development in an all-round manner, work energetically to pro- mote the country’s S&T undertak- ings and use S&T innovations to help build a harmonious society under socialism, says CAS Presi- dent LU Yongxiang in an article re- cently published in the journal Qiushi. He says the decision adopted by the Sixth Plenary Session of the Sixteenth …     

EUChinaGRID Project Officially Kicks Off

The launch meeting for the E U C h i n a G R I D (I nt er conn ecti on & Interoperability of Grids between Europe & China) Project was held on January 24 in Athens, Greece. The partners of the project include the CAS Institute of High Energy Physics, CAS Computer Network Information Center, Peking and Beihang universities from the Chi- nese side; and Istituto Nazionale di Fisica Nucleare in Italy, Università di Roma Tre in Italy, Consortium GARR in Italy, European Organiza-…     

星果草属、独叶草属、鸡爪草属的染色体观察和系统位置的探讨

1.  The present paper describes the observations of chromosome  numbers  and karyomorphology of 2 species of 2 endemic genera and I endemic species of Chinese Ranunculaceae: Asteropyrum peltatum (Franch.)  Drumm et Hutch. 2n=16, x=8; Kingdonia unifolia Balf. f. et W. W. Sm. 2n=18, x=9 and Calathodes oxycarpa Spra- gue 2n=16, x=8.  The chromosome counts of three ranunculaceous genera are repor- ted for the first time.       2.  The morphylogical, palynological and cytological date in relation to the syste- matic postition of Asteropyrum, Kingdonia and Calathodes within the family Ranun- culaceae are diseussed and resulted in following conclusions:       (1).  On the basis of the basic number x=8 in Asteropyrum, it is further con- firmed that this genus is distinct from the r elated genera such as Isopyrum, Dichocarp- um and other allied taxa.       The comparison of Asteropyrum with Coptis shows that they are identical in short chromosomes, with magnoflorina and benzylisaquinodine type of alkaloides, but dif- ferent from coptis in the chromosome numbers (T-type), pantocolpate pollens, united carpels and the dorsi-ventral type of petioles.  In view of these fundamental morpho- logical and cytological differences, Asterop yrum is better raised to the level of Tribe. However Asteropyrum and Coptis may represent two divaricate evolutional lines of Thalictroideae.       (2).  The systematic position of the genus Kingdonia has been much disputed in the past.  We support the view of Sinnote (1914), namely, the trilacunar in leaf traces “the ancient type”, appeared in the angiosperm line very early, while the uni- lacunar of Kingdonia may be derived from the trilacunar.  On the basis of the chromo- some numbers and morphylogical observation, the present writer accept Tamura’s and Wang’s treatment by keeping Kingdonia in Ranunculaceae instead of raising it to a family rank as has been been done by Forster  (1961).  Kingdonia and  Coptis are similar in having short chromosome with x=9, but with one-seeded fruits; therefore it is suggested that placed into Thalictroideae as an independent tribe, indicating its close relationship with Coptideae.        (3).  Comparing with its allies, Calathodes being with out petals, seems to be more  primitive than Trollius. But Calathodes differs from Trollius with R-type chromosomes in having T-type chromosome with x=8 and subterminal centromere.  Those charac- teristics show that it is very similar to the related genera of Thalictroideae.  But as Kurita already pointed out that most speci es of Ranunculus have usually large long chromosomes but some species have compar ativelly short chromosomes, therefore we regard T-type and R-type chromosomes appear independently in different subfamilies of Ranunculaceae. According to Tamura, G alathodes seems to be  closely related  to Megaleranthis, because of the resemblance in follicles.  But due to lack of cytological data of the latter genus, the relationship between the two genera still is not clear pen- ding further studies. From the fact that the  morphology and  chromosomes  of  the Calathodes differs from that of all other genera of the Helleboroideae, we consider Calathodes may form an independent tribe of its own with a closer relationship withTrollieae.