Observation on Chromosomes of Wildflowers in China

In this paper 7 species of wildflowers were collected from Beijing suburb and Jilin Province. They are all common sightly and hardy perennials in their localities (See the Appendix for detail of the materials). The micrographs of their somatic metaphases are shown in Plate 1; the karyotype formulae, ranges of chromosome length and classification of karyotypes according to Stebbins (1971) are shown in Table 1; the idiograms of 5 species in Figs. 1-5. The karyotype analysis is made on the basis of Li and Chen (1985)⁽¹⁾. The essential points are as follows; (1) Ten pairs of chromosomes of Achyrophorus ciliatus are all submetacentric (sm). (2) Twelve pairs of chromosomes are all metacentric (m), and the short arms of the seventh pair of chromosomes with a pair of satellites in Orychophragmus violaceus. (3) The seventh and nineth pairs of chromosomes are sm and the short arms of latter with satellites in Silene repens var. angustifolia. It is reported for the first time. (4) In Scabiosa tschiliensis. the first, fourth, fifth and eighth pairs of chromosomes are sm, the sixth is terminal (t). The second and seventh are subterminal (st), the third is m. There are satellites on the short arms of third and seventh pairs. It is reported for the first time. (5) The eleventh pair of chromosomes is sm and the others are all m. The short arms of the twelfth pairs with satellites in Lychnis fulgens. (6) The chromosome number (2n) is 42, with a pair of satellites in Papaver pseudo-radicatum. It is also reported for the first time. (7) The chromosome number is2n=56 with two pairs of satellites in Rehmannia glutinosa.     

黔桂边境六县植物区系组成及其特点

黔桂边境六县植物区系有维管束植物203科921属2255种(变种)。其中种子植物含25种以上的有22科,代表成分有樟科、山茶科、壳斗科、五加科、桑科和椴树科。区系的特点是:地理成分复杂、分布交错;热带、亚热带性质明显;区系起源古老;特有珍稀种类多;喜酸成分较喜钙成分占优势;草本与木本种类近等。此外,对本区系自然条件及植物资源利用也作了简述。     

中国大蒜芥属(十字花科)叶表皮微形态学研究

利用光学显微镜观察了中国十字花科大蒜芥属9种1变种植物的叶表皮形态。结果表明：中国大蒜芥属植物叶上表皮细胞通常为多边形,垂周壁平直或弓形,少有稍浅波状,叶下表皮细胞为不规则形,垂周壁波状或深波状;气孔器类型均以不等细胞型为主,少有无规则型,偶有平列型。依据叶表皮特征,可将中国大蒜芥属划分为三种类型： （1）叶上表皮无气孔分布或偶见; （2）叶上表皮气孔常明显几个聚成一簇或排成短列,气孔密度小于叶下表皮; （3）叶上表皮气孔比较均匀分布,气孔密度与叶下表皮近相似。     

Revision of the Genera Thyca, Stilifer, Scalenostoma, Mucronalia and Echineulima (Mollusca, Prosobranchia, Eulimidae)

All species that have been described of the genera mentioned in the title are listed and their systematic position given. The species of Stilifer (with 11 species, including S. inflatus sp.n. and 5. concavus sp.n.) are parasites of starfishes. Scalenostoma (3 species) are parasites of stone corals. Thyca (with 8 species) is removed from Capulidae, and included in Eulimidae. T. hawaiiensis sp.n. is described. The species of Thyca are parasites of starfishes. The species of Mucronalia (including M. trilineata sp.n.) are probably parasites of ophiuroids and Echineulima (with 4–6 species, including E. ponderi sp.n.) are parasites of echinoids. All species are figured, their characteristics are given and their host species and distributions are listed. Keys are given to the species of each genus, except Mucronalia. The genera Stilimella Laseron and Hyperlia Pilsbry are synonymized with Scalenostoma and the genera Kiramodulus Kuroda, Granulithyca Habe and Bessomia Berry are considered subgenera of Thyca.     

千佛山自然保护区种子植物区系特征研究

在对千佛山自然保护区详细调查的基础上,对其种子植物的科、属分布区类型进行了统计分析。结果表明:(1)保护区内种子植物丰富,共153科767属2494种;(2)优势科、属明显;(3)区系起源古老;(4)种子植物地理成分复杂,吴征镒划分的中国种子植物属的15大分布类型在千佛山均有分布;(5)种子植物区系在科和属级水平上均显示出温带性质,温带分布属475属,占总属数的61.9%;(6)特有属、种丰富。     

A Qualitative and Quantitative Study of a Sensory Epithelium in the Inner Ear of a Fish (Colisa labiosa; Anabantidae)

The macula lagenae of the anabantide fish Colisa labiosa was studied with light and transmission electron microscopy. (1) The sensory area is naturally divided in a central area (A) surrounded by a peripheral part (B). (2) Generally the central hair cells are separated by supporting cells, while the peripheral hair cells are found in groups. The cells of a group are not separated by supporting cells. (3) Tubuli-like structures, hexagonal in cross section, are found in all cells. In peripheral hair cells the longitudinally oriented tubuli-like structures are aggregated in thick bundles. (4) Variation in shape, electron density, stereocilia arrangement and size of mitochondria was found in different hair cells. (5) The central hair cells contain large accumulations of presynaptic bodies (10–44). Contrarily, the peripheral hair cells contain only a few pre-synaptic bodies (1–3). (6) The central hair cells are innervated by thick afferent (6–15 μm) and fine presumed efferent (less than 1 μm nerve fibres, while the peripheral hair cells are innervated by thin (1–6 μm) afferent nerve fibres only.     

广东石门台自然保护区的蕨类植物区系分析

通过野外调查和标本参考,广东英德石门台国家自然保护区蕨类植物区系共含47科, 96属, 293种。分析表明:(1)热带、亚热带分布性质的科为主(31科),占66.0%,非热带性分布科(16科),占34.4%。(2)热带、亚热带性质的属占优势(64属,占66.7%),其中泛热带分布属(24,25.0%)和热带亚洲分布属(19, 19.8%)是最重要的分布类型。世界分布属占26.4%,温带分布属很不明显,占7.3%。属的这种分布格局,显示出该区蕨类植物区系从热带成分向亚热带成分的渗透和过渡。(3)热带、亚热带分布种(139种)所占比例最大(47.4%),其中以热带亚洲性质的占优势(103, 35.2%);温带成分占较大的比例(34.1%)。种的分析结果与属的分析结果相差很大,出现区系相互渗透的现象。(4)在种的相似性比较上,与东部车八岭的相似性最高(38.5/59.2);与西部大瑶山种的相似性最低(21.5/35.6)。该区的蕨类植物区系与周围地区关系较为密切。     

Potentiometric characterization of ethidium bromide and of its reactions with nucleic acids

A liquid membrane electrode that allows the concentration of ethidium ion (Ed(+)) to be measured selectively and accurately in the range of 0.1 microM to 5 mM is made. For Ed(+) concentrations less than 1 microM or more than 0.1 mM, the trend is no longer linear, and the causes of this behavior are discussed. The mean activity coefficient of ethidium bromide exhibits deviations from the Debye-Huckel limiting law that are interpreted in terms of aggregate formation. The stability constants for Ed(2)(2+) and Ed(2)Br(+) are 230 kg mol(-1) and 3.0 x 10(4) kg(2) mol(-2), respectively. In NaCl solutions, clusters involving up to 4 Ed(+) units are detected and their stability constants are evaluated. The intercalation of ethidium into poly(A).poly(U) in 1M NaCl is investigated by the above electrode, and the results are compared with those obtained by spectrophotometry. The data are analyzed in terms of Scatchard plots. The potentiometric method is more accurate than the spectrophotometric one at low values of the binding degree (r) where negative deviations from linearity are observed. The deviations are ascribed to a cooperative behavior rather than to artifacts caused by minor systematic errors.     

Regional variation in SE Fennoscandian mire vegetation

The distribution in bogs is outlined for all species occurring in bogs only in part of their SE Fennoscandian area. The patterns displayed by these species are diverse, and different explanations are applicable to different patterns. Regional variation in SE Fennoscandian bog and extremely poor fen vegetation is described, based on all available published material. Carpets, lawns, and hummocks are considered separately. Four regional vegetational gradients are identified: (1) W-E, (2) S-N, (3) SW-NE, and (4) NW-SE. These are related to different underlying climatic gradients: (1) humidity (precipitation surplus), (2) temperature, (3) and (4) combinations of humidity and temperature. Effects of climatic gradients on the ground water regime are outlined. The decisive factor for the SW-NE gradient is probably frequency of ground water table fluctuations, the NW-SE gradient is likely to be caused by differences in water supply and ground water flow rates. The main gradient of carpets is S-N (SE-NW), of lawns SW-NE (W-E), and of hummocks partly SW-NE, partly S-N. The effects of the underlying ecological factors on the different plant groups are discussed in order to explain the patterns of regional variation in vegetation.     

重庆市种子植物区系特征分析

对重庆市种子植物区系进行了研究,其区系特征如下:(1)植物种类和区系组成丰富,共分布有野生种子植物208科1 127属4 764种,其科包含12种分布型和13个变型,属包含15种分布型和23个变型;(2)科的区系组成以热带成分占主要,总共包含83科,达到重庆地区种子植物总科数的39.90%,这说明重庆种子植物区系带有一定的热带亲缘关系.属的区系组成以热带成分最多,达到454属,占重庆市种子植物总属数的40.28%,表明重庆地区种子植物区系的热带亲缘关系较强;(3)特有现象明显,虽然本地区分布的特有科属相对较少,但特有种丰富.     

洛南盆地槐树坪地点2013年出土的石制品

洛南盆地槐树坪旧石器地点最初发现于1999年,该地点位于南洛河左岸(北部)支流石门河及石门河的二级支流东麻坪河(石门河一级支流为麻坪河)之间的第四级阶地上,是洛南盆地高阶地旷野旧石器地点群的代表性遗址之一。2004年4~5月和2006年6~7月,槐树坪地点曾历经两次小规模试掘。2013年4~6月,我们对该遗址进行了较大规模的系统发掘,发掘面积56 m~2,出土石锤、石料、石核、石片、工具、断块、碎屑等不同类型石制品830件。本文对2013年发掘出土的石制品进行了初步研究,统计分析结果显示,槐树坪地点加工石制品的原料来自遗址附近河流阶地砾石层中的砾石,其中以石英和石英岩为主,石英砂岩和细砂岩也有使用。剥片方式主要采用锤击法,偶见砸击法和碰砧法。石制品以中型和小型为主。工具多为石片加工而成的刮削器,偶见手斧、薄刃斧、石刀等大型工具。石器加工方向以正向居多。光释光测年数据表明,槐树坪地点埋藏石制品地层堆积物形成年代大约为距今8~9万年到1.3万年之间,其中7~8万年段的地层堆积物中包含石制品较多。槐树坪地点发现的石制品丰富了洛南盆地旧石器遗址的材料,可以使我们更深刻的了解洛南盆地高阶地旧石器遗址群的地层埋藏情况、遗址年代和石器工业内涵。     

Biochemical and genetic bases of microbial degradation of polychlorinated biphenyls (PCBs)

The microbial degradation of polychlorinated biphenyls (PCBs) has been extensively conducted by many workers, and the following general results have been obtained. (1) PCBs are degraded oxidatively by aerobic bacteria and other microorganisms such as white rot fungi. PCBs are also reductively dehalogenated by anaerobic microbial consortia. (2) The biodegradability of PCBs is highly dependent on chlorine substitution, i.e., number and position of chlorine. The degradation and dehalogenation capabilities are also highly strain dependent. (3) Biphenyl-utilizing bacteria can cometabolize many PCB congeners to chlorobenzoates by biphenl-catabolic enzymes. (4) Enzymes involved in the PCB degradation were purified and characterized. Biphenyl dioxygenase, ring-cleavage dioxygenase, and hydrolase are crystallized, and two ring-cleavage dioxygenases are being solved by x-ray crystallography. (5) The bph gene clusters responsible for PCB degradation are cloned from a variety of bacterial strains. The structure and function are analyzed with respect to the evolutionary relationship. (6) The molecular engineering of biphenyl dioxygenases is successfully performed by DNA shuffling, domain exchange, and subunit exchange. The evolved enzymes exhibit wide and enhanced degradation capacities for PCBs and other aromatic compounds.     

Seasonal changes of the Leydig cells of viscacha (Lagostomus maximus maximus). A light and electron microscopy study

The Leydig cells of viscacha (seasonal rodent) show cytoplasmic hypertrophy and regional distribution during the breeding period (summer-autumn). The dominant organelles are smooth endoplasmic reticulum (SER) and mitochondria. A moderately well-developed Golgi, abundant lipid inclusions, dense bodies like lysosomes in different stages, and centrioles are observed. Extensive or focal desmosome and gap-like junctions between neighbouring Leydig cells are present. These cells exhibit an evident hypotrophy and an increase in the number of dense bodies during the gonadal regression in winter (July and August). Cells in different stages of involution are observed in this period. Their nuclei are irregular and heterochromatic. The cytoplasm contains few mitochondria. The vesicular SER is scarse. Irregular and large intercellular spaces with microvilli and amorphous material are present. The junctional complexes are absent. The nuclear and cytoplasmic volume and development of SER and mitochondria increase during the recovery period (spring). The lipid inclusions decrease. Dilatations of the intercellular space with microvilli and limited by focal desmosome-like junctions are observed. In conclusion, the Leydig cells of Lagostomus maximus maximus show deep changes alongside the reproductive cycle. The photoperiod variations, through pineal hypothalamus pituitary axis and the hormone melatonin, are probably responsible for them. Moreover, the fall of serum and tubular testosterone would be one of the factors responsible for gonadal regression.     

Application of particle swarm optimization and proximal support vector machines for fault detection

This paper presents a novel application of particle swarm optimization (PSO) in combination with another computational intelligence (CI) technique, namely, proximal support vector machine (PSVM) for machinery fault detection. Both real-valued and binary PSO algorithms have been considered along with linear and nonlinear versions of PSVM. The time domain vibration signals of a rotating machine with normal and defective bearings are processed for feature extraction. The features extracted from original and preprocessed signals are used as inputs to the classifiers (PSVM) for detection of machine condition. Input features are selected using a PSO algorithm. The classifiers are trained with a subset of experimental data for known machine conditions and are tested using the remaining data. The procedure is illustrated using the experimental vibration data of a rotating machine. The influences of the number of features, PSO algorithms and type of classifiers (linear or nonlinear PSVM) on the detection success are investigated. Results are compared with a genetic algorithm (GA) and principal component analysis (PCA). The PSO based approach gave test classification success above 90% which were comparable with the GA and much better than PCA. The results show the effectiveness of the selected features and classifiers in detection of machine condition.     

Asexual propagation and reproductive strategies in aquatic Oligochaeta

A great variety of asexual reproductive modes are known among aquatic oligochaetes. The main types of these modes are shortly described. Based upon observations on natural populations, the possible genetical and ecological implications of asexual reproduction are discussed. The following points are emphasized: (1) The often expressed expectations of a strong predominance of one particularly adaptive genotype is not born out. (2) In most cases, a number of genetically distinct clones are present in each population, and they show a strong differential distribution in heterogeneous environments, indicating an effective exploitation of the available resources. (3) Most cases of asexual propagation are reproductive strategies of their own and not escape mechanisms. (4) The mechanisms underlying asexual propagation are complex and involve many aspects of the life history. The great variety of types among aquatic oligochaetes offer particularly useful models for the study of these problems.     

Chromosome Studies of 10 Chinese Species of Adenophora Fisch.

This paper is a cytological part of biosystematic studies on Adenophora Fisch. in Heilongjiang, China. Chromosomal numbers and karyotypes of 10 spp. and 1 var. are reported. The results are summarized in Table 1. The chromosomal numbers and karyotypes of 6 spp. and 1 var. are first reported, including tetraploid species (2n=68) (A. pereskiifolia var. alternifolia, A. amurica and A. gmelinii). The basic number of chromosomes in the genus is mainly 17 (x=17), but that of A. trachelioides and A. remotiflora (2n=36) is 18 (x=18), an unique one in the genus. The karyotypes of all the species examined are relatively uniform, which means that they are derived from a common ancestral type. The chromosomes are smaller, varying between 2-4 μm. The majority of chromosomes are m and sm ones. And a pair of sat-chromosomes and a pair of st chromosomes are always present. The centromeric terminalization value of chromosomes is 57.5-61.9%, showing higher symmetry of karyotypes in the genus. The karyotype of A. tetraphylla (2n=34) is the most symmetrical among these species. Based on its morphological characters and distribution, the species may be considered as a relatively primitive member of the genus. The results show two revolutionary trends in karyotypes of the genus: number variation (including polyploidy and aneuploidy) and structural variation. The polyploidy is one of the principal patterns of speciation in the genus. Combined with the other characters, these species are taxonomically discussed, and two new taxa (A. amurica Fu et Liu and A. pereskiifolia ssp. alternifolia (Fuh ex Y. Z. Zhao) Fu et Liu) are confirmed. A. trachelioides and A. remotiflora (both 2n=36) with obvious petioles seems more advanced than the other species (2n 34).     

Pollen Morphology of the Family Zingiberaceae in China—Pollen Types and Their Significance in the Taxonomy

Pollen morphology of 89 species and 3 varieties belonging to 18 genera (out of 150 spcies in 20 genera) of Zingiberaceae in China was studied under both light microscope and scanning electron microscope. Pollen grains of Zingiberaceae are spherical, subspherical, ovoid and prolate, 36-225 μm in size, nonaperturate or aperturate (spiraperturate, porate). Pollen grains are almost not resistant to acetolysis. The wall is composed of a very thin exine and a thick intine. The exine is psilate, spinate, cerebelloid-areolate, striate, verrucate and foveolate. According to the presence or the absence of aperture and differential ornamentations, two types and six subtypes are recognized: I. The type Nonaperturate: (85 species and 3 varieties in 18 genera). Four subtypes can be recognized within the type based on the characteristics of the exine sculpture. These are: (1) The subtype Psilate, in which, the exine is nearly smooth (including: Hedychium, Curcuma, Kaempferia, Caulokaempferia coenobilis, Boesenbergia rotunda, Stahlianthus, Amomum compactum, Etingera, Hornstedtis, Rhynchanthus). (2) The subtype Spinate, which comprises two groups: (A) The group Short-spinate, pollen grains with smaller spines (Globba), (B) The group Long-spinate, pollen grains with longer spines (Alpinia, Amomum, Plagiostachys, Roscoea, Cautleya, Boesenbergia fallax, Caulokaempferia yunnanensis). (3) The subtype Cereblloid-areolate, pollen grains of which are spherical or subspherical, with cerebelloid sculpture (Zingiber Sect. Zingiber). (4) The subtype Striate, pollen grains of which are prolate or oliveshaped, and striate (Zingiber Setc. Cryptanthium). II. The type Aperturate, in which pollen grains are acetilysis-resistant and possess distinct apertures (mixed colpate-porate or forate), including two subtypes: (1)The subtype Mixed colpate and Porate. Pollen grains are both 3-colpate and 1-3-porate, and usually with one long spiral, two short (straight or slightly curved) colpi and 1-3-poris. The exine is verrucate or not, nearly sinuolate (Costus speciosus, C. tonkinensis, C. lacerus). (2) The subtype porate, whose grains are 6-8-porate and exine is foveolate (Costus megalobractea). The taxonomic significance of the pollen types in the family Zingiberaceae is also discussed.     

Freshwater fish at risk or extinct in México

The Mexican freshwater fish that are at risk orextinct are listed by family, state,basin/region, and causes of risk. Of the 506known species, 168 are at some level of risk,and 25 are believed to be extinct. States withthe most reports are: Chihuahua (46); Coahuila(35); Nuevo León (20); Sonora (19); Durango(18); and Tamaulipas (15). With the exceptionof Sonora, these states are largely located inthe Río Bravo region, and are all arid orsemiarid. Most extinctions have occurred inNuevo León (8) and Coahuila (7). The maincauses of risk reported are: habitat reductionor alteration (86); water depletion (83);presence of exotics (76); small or decliningpopulation (73); and small habitat (57). Allof which result in very local endemism. Thesecauses of risk develop easily when thedistribution is small. The critical factor isaridity, which is associated withdesertization. Water conflicts were to beexpected, and the result is resource nonsustainability.     

The fine structure of the dorsal column nucleus and the nucleus of bischoff of the python (Python reticulatus)

Three types of neuronal perikaryal profiles were identified in the dorsal column nucleus and the nucleus of Bischoff of the python (Python reticulatus). Type I neuronal profiles are large (diameters 12–20 μm) with a deeply indented uncleus. The cisterns of rough endoplasmic reticulum (rER) are mostly randomly dispersed. Axosomatic synapses are few. Type II neuronal profiles (9–11 μm) have a smooth, round, or slightly oval nucleus. Several small stacks of rER are present. Type III neuronal profiles (8–10 μm) have little cytoplasm. The nuclear margin is irregular but not deeply infolded. The rER usually consists of a single long perinuclear ribosome-studded cistern. Two types of astrocytic profiles have been identified. Both types contain abundant filaments. Type I astrocytes are large cells, and the nucleus is very irregular in shape. Type II astrocytes are smaller and are found among the myelinated axons in the dorsal funiculus. Two classes of axon terminals have been identified. One class contains round synaptic vesicles (R profiles) and the other flattened vesicles (F profiles). Some R profiles are small (SR profiles), others are large (LR profiles). Some R profiles also contain a few large, dense-cored vesicles. The R and F profiles establish axodendritic and axoaxonal synapses, some of which are located in the synaptic glomeruli and others in the extraglomerular neuropil. In most of the axoaxonal synapses, the presynaptic element is an F profile and the post synaptic element an LR profile. Occasionally, LR profiles are presynaptic to F profiles. The findings in the python are compared with those of the dorsal column nuclei of the rat, cat, and monkey.     

The carbonate radical is a site-selective oxidizing agent of guanine in double-stranded oligonucleotides

The carbonate radical anion (CO(3)) is believed to be an important intermediate oxidant derived from the oxidation of bicarbonate anions and nitrosoperoxocarboxylate anions (formed in the reaction of CO(2) with ONOO(-)) in cellular environments. Employing nanosecond laser flash photolysis methods, we show that the CO(3) anion can selectively oxidize guanines in the self-complementary oligonucleotide duplex d(AACGCGAATTCGCGTT) dissolved in air-equilibrated aqueous buffer solution (pH 7.5). In these time-resolved transient absorbance experiments, the CO(3) radicals are generated by one-electron oxidation of the bicarbonate anions (HCO(3)(-)) with sulfate radical anions (SO(4)) that, in turn, are derived from the photodissociation of persulfate anions (S(2)O(8)(2-)) initiated by 308-nm XeCl excimer laser pulse excitation. The kinetics of the CO(3) anion and neutral guanine radicals, G(-H)( small middle dot), arising from the rapid deprotonation of the guanine radical cation, are monitored via their transient absorption spectra (characteristic maxima at 600 and 315 nm, respectively) on time scales of microseconds to seconds. The bimolecular rate constant of oxidation of guanine in this oligonucleotide duplex by CO(3) is (1.9 +/- 0.2) x 10(7) m(-1) s(-1). The decay of the CO(3) anions and the formation of G(-H)( small middle dot) radicals are correlated with one another on the millisecond time scale, whereas the neutral guanine radicals decay on time scales of seconds. Alkali-labile guanine lesions are produced and are revealed by treatment of the irradiated oligonucleotides in hot piperidine solution. The DNA fragments thus formed are identified by a standard polyacrylamide gel electrophoresis assay, showing that strand cleavage occurs at the guanine sites only. The biological implications of these oxidative processes are discussed.