Morphological Difference and Karyotype of Pelteobagrus fulvidraco in Dongting Lake Water System

[Objective] The research aimed to study the morphological characteristics and karyotype of Pelteobagrus fulvidraco in Dongting Lake water system.[Method] By using the conventional biological morphometry,PHA and colchicine injection method in vivo,the morphological characteristics and karyotype of P.fulvidraco in Yuanshui River and Lishui River of Dongting Lake were analyzed.[Result] In three ratio traits including standard length/head length,standard length/caudal peduncle depth,head length/snout length,P.fulvidraco of Yuanshui River and Lishui River had significant differences（P0.05）.However,the number and karyotype of their chromosomes were same.The chromosome number was 2n = 52,and the karyotype formula was 20M＋12SM＋10ST＋10T.The number of chromosome arm was 84.[Conclusion] The research result had certain theoretical guidance significance for the protection and utilization of wild P.resource in Dongting Lake water system.

中药防风的高产栽培技术

介绍了防风的形态特征,采用文献综述和调查研究的方法研究了高产栽培以及病虫害的防治措施,以期提高防风的产量。

Morphological Analysis and Gene Mapping of a Rice Dwarf Mutant

[Objective] This study aimed to conduct morphological analysis and gene mapping of a rice dwarf mutant. [Method] A dwarf mutant （Xiaoxiang＇ai） was used as test material for morphological observation. Xiaoxiang＇ai was used as female parent and semi-dwarf material Xiangzao143 was used as male parent to construct populations for genetic analysis. Gene mapping was conducted by using micro- satellite markers. [Result] The average height of Xiaoxiang＇ai was 55 cm; genetic analysis results showed that plant height of F1 individuals was similar with the male parent, while semi-dwarf plants and dwarf plants were observed in F2 populations and the segregation ratio was nearly 3：1, indicating that plant height trait of Xiaoxi- ang＇ai is mainly controlled by one pair of recessive gene located on rice chromo- some 5 and in the upstream of RM249, with a genetic distance of 8.4 cM. [Conclu- sion] rRH is a new dwarf gene in rice.

Blind Source Separation based on Time-Frequency Morphological Characteristics for Rigid Acoustic Scattering by Underwater Objects

Separation of the components of rigid acoustic scattering by underwater objects is essential in obtaining the structural characteristics of such objects. To overcome the problem of rigid structures appearing to have the same spectral structure in the time domain, time-frequency Blind Source Separation （BSS） can be used in combination with image morphology to separate the rigid scattering components of different objects. Based on a highlight model, the separation of the rigid scattering structure of objects with time-frequency distribution is deduced. Using a morphological filter, different characteristics in a Wigner-Ville Distribution （WVD） observed for single auto term and cross terms can be simplified to remove any cross-term interference. By selecting time and frequency points of the auto terms signal, the accuracy of BSS can be improved. A simulation experimental has been used to analyze the feasibility of the new method, with changing the pulse width of the transmitted signal, the relative amplitude and the time delay parameter. And simulation results show that the new method can not only separate rigid scattering components, but can also separate the components when elastic scattering and rigid scattering exist at the same time. Experimental results confirm that the new method can be used in separating the rigid scattering structure of underwater objects.

A new record of Sebastes koreanus from China based on morphological characters and DNA barcoding

A new record of Sebastes koreanus （Kim and Lee, 1994） was documented based on morphological characters and DNA barcoding. Fifty-six Sebastes specimens were collected from the coastal waters of northern China. Samples were identified as S. koreanus based on morphological characters. The coloration and morphometric measurements were consistent with those described from specimens collected in South Korea. In this study, specimens had the following morphological characteristics： light brown body with dark stripes and tiny dark spots, 4-5 wide indistinct vertical patterns on the side, 2 radial stripes behind and below the eyes, 1 large dark blotch on the opercle. Additionally, the following meristie characters were recorded： dorsal fin XIV-13, pectoral fin 16, anal fin III-6-7, pelvic fin [-5, lateral line scales 29-30, and vertebrae 26. The fragment of cytochrome oxidase subunit I （CO1） gene of mitochondrial DNA was sequenced for phylogenetic analysis. The mean genetic distance within the species was 0.3%. Net genetic distances between S. koreanus and other Sebastes species ranged from 3.1% to 7.6%, which was greater than the threshold for species delimitation. The phylogenetic analysis strongly supports the validity of S. koreanus in China at the genetic level. The origion, evolution, patterns of speciation and unique features in genome divergence among primate lineages of this species still need future directions of research.

Morphological Studies on the Infraciliature of a Planktonic Ciliate,Tintinnopsis brasiliensis(Ciliophora:Tintinina)

A poorly-described marine planktonic ciliate, Tintinnopsis brasiliensis Kofoid ＆ Campbell, 1929, collected from the Taiping Cape of Qingdao, China, was morphologically investigated based on permanent preparation after protargol impregnation and was compared with other related congeners. According to the infraciliature, three ciliary groups can be recognized, which reveals a very stable structure among specimens and denotes that the pattern of infraciliature is, apart from the features of the lorica, a highly reliable criterion for species identification.

An integrative study of larval organogenesis of American shad Alosa sapidissima in histological aspects

We describe organogenesis at a histological level in American shad( Alosa sapidissima) larvae from 0 until 45 days after hatching(DAH). Larval development was divided into four stages based on the feeding mode,external morphological features,and structural changes in the organs: stage 1(0–2 DAH),stage 2(3–5 DAH),stage 3(6–26 DAH) and stage 4(27–45 DAH). At early stage 2(3 DAH),American shad larvae developed the initial digestive and absorptive tissues,including the mouth and anal opening,buccopharyngeal cavity,oesophagus,incipient stomach,anterior and posterior intestine,differentiated hepatocytes,and exocrine pancreas. The digestive and absorptive capacity developed further in stages 2 to 3,at which time the pharyngeal teeth,taste buds,gut mucosa folds,differentiated stomach,and gastric glands could be observed. Four defined compartments were discernible in the heart at 4 DAH. From 3 to 13 DAH,the excretory systems started to develop,accompanied by urinary bladder opening,the appearance and development of primordial pronephros,and the proliferation and convolution of renal tubules. Primordial gills were detected at 2 DAH,the pseudobranch was visible at 6 DAH,and the filaments and lamellae proliferated rapidly during stage 3. The primordial swim bladder was first observed at 2 DAH and started to inflate at 9 DAH; from then on,it expanded constantly. The spleen was first observed at 8 DAH and the thymus was evident at 12 DAH. From stage 4 onwards,most organs essentially manifested an increase in size,number,and complexity of tissue structure.

Studies on the mitotic chromosome scaffold of Allium sativum

An argentophilic structure is present in the metaphase chromosomes of garlic (Allium sativum). Cytochemical studies indicate that the main component of the structure is non-histone proteins (NHPs). The results of light and electron microscopic observations reveal that the chromosme NHP scaffold is a network which is composed of fibres and granules and distributed throughout the chromosomes. In the NHP network, there are many condensed regions that are connected by relatively looser regions. The distribution of the condensed regions varies in individual chromosomes. In some of the chromosomes the condensed regions are longitudinally situated in the central part of a chromatid while in others these regions appear as coillike transverse bands. At early metaphase, scaffolds of the sister chromatids of a chromosome are linked to each other in the centromeric region, meanwhile, they are connected by scafold materials along the whole length of the chromosome. At late metaphase, however, the connective scaffold materials between the two sister chromatids disappear gradually and the chromatids begin to separate from one another at their ends, but the Chromatids are linked.together in the centromeric region until anaphase. This connection seems to be related to the special structure of the NHP scaffold formed in the centromeric region. The morphological features and dynamic changes of the chromosome scaffold are discussed.

Variability in the Content of 25α- and 25β-Steroidal Sapogenins among Thirty Morphologically Different Sudanese Seed Accessions of Fenugreek

Seeds of Fenugreek （Trigonellafoenum-graecum L.）, an international spice commodity, are much consumed in Sudan as a food, for flavoring and as a folk-remedy for several ailments, together with local beliefs in nutraceutical benefits. The authors have noted an immense variability in colour and other morphological characters of Fenugreek seeds offered in local Sudanese markets and wondered whether this variability is extended to their chemical composition. Steroidal sapogenins are important chemical constituents of Fenugreek seeds in view of their potential as precursors for the commercial synthesis of steroid drugs and their continually revealed beneficial biological activities. In this study, thirty Sudanese Fenugreek seed accessions collected from different geographical regions in Sudan were analyzed for their 25α-, 25β- and total sapogenin content using a simple and specific infra-red spectroscopic method. The seed accessions exhibited much morphological variability particularly in outer seed coat color and size. Preparative TLC followed by gravimetric analysis showed that steroidal sapogenins, mostly diosgenin and yamogenin, represented more than 70% of the steroids of Fenugreek seeds. Infra-red spectroscopic analysis showed that total 25α-sapogenins （calculated as diosgenin） varied from 0.65% to 1.68%. Total 25β-sapogenin （calculated as yamogenin） varied from 0.38% to 2.03%. The content of total sapogenins （α ＋ β epimeric forms） varied between 1.24% and 3.0% of the oven-dry weight of seeds. β-sapogenins （mostly yamogenin） were dominant over α-sapogenins （diosgenin） in most Sudanese Fenugreek seed accessions.

Bacteriophage Morphological Characterization by Using Transmission Electron Microscopy

Bacteriophages or more commonly ＂phages＂ are bacterial viruses. They are ubiquitous and good indicators of bacterial contaminations since their prevalence is high in those environments where their hosts are abundant. Phage classification is based on morphology and for this reason, even though it is considered an old technique, TEM （Transmission Electron Microscopy） still plays a key role in their characterization. In the present work, the authors focused on TEM analysis of phage ФApr-1 isolated against Lactococcuslactis （L. lactis）, implicated in industrial fermentations and of phage ФIZSAM-1, active against Listeria monocytogenes （L. monocytogenes）, isolated from the environment. For observation with TEM （EM 900T-Zeiss）, phages were harvested in liquid media and were negative stained with fosfotungstic acid 2‰. An accurate viral ultrastructure analysis by using TEM is fundamental not only in the first approach of characterization of newly isolated phages but also for providing useful information to go further to the selection process as potential bio-decontaminants.

Molecular Phylogenetic Lineage of Plagiopogon and Askenasia(Protozoa, Ciliophora) Revealed by Their Gene Sequences

Prostomates and haptorians are two basal groups of ciliates with limited morphological characteristics available for tax- onomy. Morphologically, the structures used to identify prostomates and haptorians are similar or even identical, which generate heavy taxonomic and phylogenetic confusion. In present work, phylogenetic positions lineage of two rare genera, Plagiopogon and Askenasia, were investigated. Three genes including small subunit ribosomal RNA gene （hereafter SSU rDNA）, internal transcribed spacer region （ITS region）, and large subunit ribosomal RNA gene （LSU rDNA） were analyzed, 10 new sequences five species each. Our findings included 1） class Prostomatea and order Haptorida are multiphyletic; 2） it may not be appropriate to place order Cyclotriehiida in subclass Haptoria, and the systematic lineage of order Cyclotrichiida needs to be verified further; 3） genus Plagio- pogon branches consistently within a clade covering most prostomes and is basal of clade Colepidae, implying its close lineage to Prostomatea; and 4） Askenasia is phylogenetically distant from the subclass Haptoria but close to classes Prostomatea, Plagiopylea and Oligohymenophorea. We supposed that the toxicyst of Askenasia may be close to taxa of prostomes instead of haptorians, and the dorsal brush is a more typical morphological characteristics of haptorians than toxicysts.

Growth and morphological characterization of zinc nanoplates

Zinc nanoplates were grown using thermal evaporation without catalyst or template involved.Tunneling electron microscopy and selected area electron diffraction analyses showed that the plates were single crystals with either {0001} or {11 20} as basal surfaces.The morphological characteristics were explained in terms of the intrinsic growth anisotropy of zinc,the surface energy of the nano-crystals,the size of the critical nucleus and the migration of the adatoms.Our results suggested a promising low-cost route for synthesis of pure zinc nanoplates which could be used as precursor for further preparing core-shell nanoplate structures.

Effect of Exposing Low-Frequency Electric Fields on the Proliferative Capacity and Morphological Features of Olfactory Ensheathing Cells in vitro

Olfactory ensheathing cells(OECs) transplanted into the damaged spinal cord may be considered as a valuable remedy explorations for spinal cord repair. The proliferation of transplanted olfactory ensheathing cells depends on various environmental factors and effective cues, which may include electrical fields(EFs). In this study, we investigated the proliferative capacity, morphologic alterations of olfactory ensheathing cells derived from neonate rat that occurd when exposed to two EFs of 20 Hz, 50 mV and20 Hz, 100 mV for 6 h. For both EF treatments, the MTT results revealed that the cellular proliferation of exposed group during the last 6 h of the experiment was statistically higher than that of control group. Then, we investigated morphological structure changes in the cells stained by Coomassie brilliant blue. Compared with control group, most of cells were present at intensively proliferating appearance including the microfilaments were long and thick and the accumulated appearance of cells. It is conceivable that electrical fields as a new approach may promote the growth and proliferation of OECs and may be engineered to control the survival of transplanted OECs in injured spinal cord.Although our results have been suggesting that EFs may be non-chemical strategies for cell proliferation, the fundamental mechanisms remain to be elucidated.