28 resultados para lip
Resumo:
The type species of the cyprinid genus Sinilabeo was misidentified as Varicorhinus tungting, and the species under the generic name belong to Bangana and Linichthys. In order to make Sinilabeo available, its type species is fixed under Article 70.3.2 of the 1999 edition of the International Code of Zoological Nomenclature as S. hummeli, a new species herein described from the upper Yangtze River basin in Chongqing City and Sichuan Province, South China. A re-definition is provided for Sinilabeo. It resembles Qianlabeo in having an upper lip only present in the side of the upper jaw and uncovered by the rostral fold, but missing in the median part of the upper jaw that, instead, bears a thin, flexible, and cornified sheath, covered by the rostral fold, a character that can separate both from all other existing genera of Asian labeonins. However, Sinilabeo is distinguished from Qianlabeo in the presence of a rostral fold disconnected from the lower lip; a broadly interrupted postlabial groove only restricted to the side of the lower jaw; an upper lip, which is only present in the side of the upper separated from it by a groove; 9-10 branched dorsal-fin rays; two pairs of tiny maxillary barbels.
Resumo:
Phylogenetic relationships of labeonine cyprinids of the disc-bearing group (Pisces. Teleostei). Zoological Studies 44 (1): 130-143. The disc-bearing group is composed of 4 currently recognized cyprinid genera: Discocheilus, Discogobio, Garra, and Placocheilus. This group is defined as having a lower lip modified to form a mental adhesive disc whose posterior margin is not continuous with the mental region, and includes 91 widely distributed species in tropical Africa and Asia. So far, it is represented in China by 28 species (about 1/3 of the total number) of all 4 genera. A phylogenetic analysis, based on 29 morphological characters scored from first-hand observations of 23 of the Chinese species examined, revealed that the disc-bearing group forms a monophyletic clade in which Garra is the basal lineage, and Placocheilus constitutes a subclade with the sister pair of Discocheilus and Discogobio. In such a phylogenetic framework, the validity of each genus of the disc-bearing group was evaluated. It was confirmed that Discocheilus, Discogobio and Placocheilus represent 3 valid cyprinid genera. Evidence provided in this phylogenetic analysis, incorporated with conclusions reached in the known literature, reveals that the monophyly and validity of Garra need to be further studied using observations of more Garra species. Additional characters should also be examined, as the characters utilized in this study and in Abebe's with Getahun's (1999) study are insufficient to resolve the monophyly of Garra.
Resumo:
yLinichthys, new genus, is proposed for Barbodes laticeps Lin and Zhang, 1986. It can be separated from all other genera of Asian Barbinae in having a shallow depression extending along the median portion of the upper lip. Linichthys is superficially very similar to the type species of a monotypic Chinese cyprinid cavefish genus, Typhlobarbus nudiventris, in having an elongate and somewhat compressed body form, a truncate distal margin of the dorsal fin, and a soft and smooth last unbranched dorsal-fin ray, all of them being atypical for most of Asian barbins. The two genera differ in size of the eye and the number of rows of pharyngeal tooth. Although the same body form and/or structure of the dorsal fin are also shared with some species currently placed in other genera of Asian barbins, the recognition of Linichthys is warranted because of their marked differences in other characters. A redescription is also provided for the type species of the monotypic genus, Linichthys laticeps. It is known only from the upper and middle Zhu Jiang basin and the upper Chang Jiang basin in the city of Guiyang, Guizhou Province, South China.
Resumo:
Qianlabeo striatus gen. et sp. nov. is described from a stream tributary to the Beipan Jiang of the upper Zhu Jiang (Pearl River) drainage in Matou, Anshun County, Guizhou Province, China. This monotypic genus is mainly characterized by its oromadibular morphology, namely an upper lip only present in and fully adnate to the side of the upper jaw, not covered by the pendulous rostral fold; the median portion of the upper jaw lacking an upper lip but bearing a thin, flexible and cornified cutting edge that is fully covered by the pendulous rostral fold; a postlabial groove prolonged, extended anteromedially close to the anteromost point of the midline of the lower lip but not to meet with its counterpart. The type species of this genus, Q. striatus has a longitudinal dark stripe along the side of the body.
Resumo:
Tylopharynx clariamphida sp. n. is described from muddy sand collected in Anhui Province, China. It can be distinguished from T foetida (Butschli, 1874), the type and only species of the genus, by numerous characters: having 24 to 26 prominent and clearly separated longitudinal ridges, a higher lip region with no hint of a cephalic framework, more prominent amphidial foveae in lateral view, wider and more posteriorly located amphidial apertures, smaller basal knobs of stoma, longer metacorpus, more enlarged phasmids, shorter spicules with shorter digitate terminus, shorter reflexed part of testis, and thicker gubernaculum with more angular shape. For comparison, an expanded description is given for T foetida from Belgium, and SEM photographs of both species are provided.
Resumo:
Phylogenetic relationships among six species of Epistylis (i.e. E. plicatilis, E. urceolata, E. chrysemydis, E. hentscheli, E. wenrichi, and E, galea) were investigated using sequences of the first internal transcribed spacer region (ITS-1) of ribosomal DNA (rDNA). Amplified rDNA fragment sequences consisted of 215 or 217 bases of the flanking 18S and 5.8S regions, and the entire ITS-1 region (from 145 to 155 bases). There were more than 33 variable bases between E. galea and the other five species in both the 18S region and the ITS-1 region. The affiliation of them was assessed using Neighbor-joining (NJ), maximum parsimony (MP) and maximum likelihood (ML) analyses. In all the NJ, MP and ML analyses E. galea, whose macronucleic position and shape are distinctly different from those of the other five species, was probably diverged from the ancestor of Epistylis earlier than the other five species. The topology in which E. plicatilis and E, hentscheli formed a strongly supported sister clade to E. urceolata, E. chrysemydis, and E. wenrichi was consistent with variations in the thickness of the peristomial lip. We concluded that the macronucleus and peristomial lip might be the important phylogenetic characteristics within the genus Epistylis.
Resumo:
The peritrichs have been recognized as a higher taxon of ciliates since 1968. However, the phylogenetic relationships among them are still unsettled, and their placement within the class Oligohymenophorea has only been supported by the analysis of the small subunit rRNA gene sequence of Opisthonecta henneguyi. DNA was isolated directly from field-sampled species for PCR, and was used to resolve relationships within the genus Epistylis and to confirm the stability of the placement of peritrichs. Small subunit rRNA gene sequences of Epistylis plicatilis, Epistylis urceolata, Epistylis chysemydis, Epistylis hentscheli, Epistylis wenrichi, and Vorticella campanula were sequenced and analyzed using both distance-matrix and maximum-parsimony methods. In phylogenetic trees, the monophyly of both the genus Epistylis and the subclass Peritrichia was strongly supported, while V. campanula clustered with Vorticella microstoma. The topology in which E. plicatilis and E. hentscheli formed a strongly supported sister clade to E. urceolata, E. chrysemydis, and E. wenrichi was consistent with variations in the thickness of the peristomial lip. We concluded that the peristomial area, especially the. peristomial lip, might be the important phylogenetic character within the genus Epistylis.
Resumo:
Directional emission triangle and square InGaAsP/InP lasers have been fabricated by standard photolithography, inductively coupled plasma etching technique combined with wet chemical etching process. In this article, the characteristics of the microcavity lasers are presented. For an equilateral triangle microcavity laser with the side length of 30 mu m, we got the laser spectra fitted very well with the mode wavelength formulate LIP to the 8(th) transverse mode at room temperature. But the laser spectra are usually more complex than the formulae for the lasers, especially for the lasers with a smaller side length. For a square microcavity laser with side length of 20 mu m, we observed the mode competition between the Fabry-Perot (FP) modes and Whispering-Gallery (WG) modes at 200K. The output spectra below the threshold have the mode interval of FP modes with a large mode interval, and the laser spectra agree very well with the WG modes, which have mode interval less than the FP modes. The output spectra are dominated by the FP modes below the threshold, because the FP modes have a higher output coupling efficiency than the WG modes.
Resumo:
对15株白腐真菌进行了以玉米秸秆为基质的初步筛选,从中获得一株选择性系数较高的菌株Y10,并对其降解玉米秸秆的情况进行了研究。结果表明,在30天的培养过程中菌株Y10对玉米秸秆降解的选择性系数都大于1,第15天选择性系数最高为3.88。对未经降解和降解过的玉米秸秆分别作了紫外光谱和红外光谱分析,结果表明,经该菌降解后玉米秸秆的化学成分发生了很大变化,且木质素的降解程度要大于纤维素的降解程度。对菌株Y10进行了ITS-5.8S rDNA序列鉴定,初步判定其为Cerrena sp.。 为了考查不同的外源添加物对菌株Y10降解玉米秸秆的影响,在以玉米秸秆为基质的固态发酵培养基中分别添加了7种金属离子、8种碳源、6种氮源。结果显示,这7种金属离子均能促进木质素的降解,并且一定浓度的某些离子明显抑制纤维素的降解;其中添加0.036%的MnSO4·H2O和0.36%的MgSO4·7H2O对纤维素降解的抑制作用比较强,降解率分别为0.96%和1.31%,木质素的选择性系数分别达到了34.40和20.17。8种碳源中除麦芽糖外都能促进木质素的降解,除微晶纤维素外都明显促进纤维素的降解。6种氮源中酒石酸铵、硫酸铵、草酸铵和氯化铵的添加都会使该菌生长变慢,而且氮源浓度越高菌丝生长越慢。外加碳源和金属离子对半纤维素降解和选择性系数的影响不大。 同时对菌株Y10在液态培养下产木质素降解酶的条件和培养基做了优化。结果表明,在初始产酶培养基中,菌株Y10的漆酶酶活在第10d达到最高,锰过氧化物酶酶活在第11d达到最高,基本上检测不到木质素过氧化物酶。菌株Y10产漆酶的最适温度为32℃,最适PH为6.0;产锰过氧化物酶的最适温度为32℃,最适PH为6.5。菌株Y10产漆酶的最佳碳源为甘露糖,最佳氮源为酒石酸铵,最适诱导剂VA浓度为3 mmol/L,最适表面活性剂TW-80浓度为1%。 利用响应面法对其产漆酶的培养基进行优化,优化后的培养基配方为葡萄糖10.00 g/L,酒石酸铵0.50 g/L,大量元素296.50 ml/L,微量元素100.00 ml/L,NTA 1.40 g/L,VA 5.00 mmol/L,吐温-80加入量为0.10%。进行了菌株Y10产漆酶的验证实验,实测酶活为5282.56 U/L,与预测酶活5162.73 U/L接近。在优化后培养基中,菌株Y10在第14 d达到生长的最高峰,第20 d时,漆酶酶活最高,为11325.00 U/L;第16 d时,锰过氧化物酶酶活最高,为30.77 U/L。 对菌株Y10的漆酶酶学性质做了初步的研究,结果显示,酶反应的最适温度为40℃-65℃,最适PH为3.0。在40℃,PH=3.0时,漆酶催化ABTS反应的米氏方程为 。 Fifteen white-rot fungi based on corn stalk were screened. One white-rot fungus Y10 with high selectivity value was obtained. The degradation of corn stalk was initially studied. The results indicated that the selectivity value was above 1 during the 30 day-cultivation and the highest was 3.88 after 15 days. The composition of untreated and treated stalk was analyzed through ultraviolet spectroscopy and infrared spectroscopy. It was found that the composition of treated stalk was greatly altered and the degree of the degradation of lignin is greater than the cellulose. Y10 was identified as Cerrena sp. by ITS -5.8S rDNA sequence analysis. The influence of metal ions, carbon sources and nitrogen sources on corn stalk degradation by white-rot fungus was studied. While all seven metal ions could promote lignin degradation, the cellulose degradation was best inhibited at certain ion concentrations. Notably, when 0.036% MnSO4·H2O and 0.36% MgSO4·7H2O were added into the medium, the cellulose degradation was restrained to the extents that the coefficients of lignin selectivity rose to 34.40 and 20.17 respectively. It was also found that all carbon sources except maltose can promote lignin degradation. The addition of carbon sources other than microcrystalline cellulose significantly promoted cellulose degradation. The addition of the nitrogen sources, ammonium tartrate, ammonium sulfate, oxalate, ammonium chloride, resulted in remarkable inhibition to mycelium growth; the larger the concentrations of nitrogen sources are, the slower the mycelium grew. The addition of carbon sources and metal ions had less impact on the degradation of hemicellulose and selectivity value. Meanwhile, we optimized the conditions and culture medium of the lignin-degrading enzyme production of strain Y10. The results showed that in the initial culture medium, the Lac activity was highest at the 10th day, the MnP activity was highest at the 11th day and the LiP could not be detected. The optimum condition of Lac was at temperature 32 and PH =6.0 and the optimum condition of MnP was at temperature 32 and PH =6.5. The optimum carbon source for Lac was seminose, the optimum nitrogen source was ammonium tartrate, the optimum content of VA was 3 mmol/L, the optimum content of TW-80 was 1%. PB and RSM were used to optimize the culture medium of laccase by white-rot fungus Y10. The optimum culture medium was consist of glucose 10.00 g/L, ammonium tartrate 0.50 g/L, macro elements 296.50 ml/L, trace elements 100.00 ml/L, NTA 1.40 g/L, VA 5.00 mmol/L, TW-80 0.10%. Under the optimal conditions, the activity of laccase was 5282.56 U/L and the experimental value agreed with the predicted value 5162.73 U/L. The biomass was highest at the 14th day, the Lac activity was highest at the 20th day, the MnP activity was highest at the 16th day. The results of the studies on the characteristics of Lac showed that the optimum temperature for Lac activity is 40℃-65℃ ; the optimum PH for Lac activity is 3.0 and under 40℃,PH=3.0, the Michaelis-menten equation of Lac catalized ABTS oxidation was .
Resumo:
A series of novel neutral nickel complexes 4a-e bearing modified beta-ketoiminato ligands [(2,6-(Pr2C6H3)-Pr-i)N=C(R-1)CHC(2 '-R2C6H4)O]Ni(Ph)(PPh3) (4a, R-1 R-2 = H; 4b, R-1 = H, R-2 = Ph; 4c, R-1 = H, R-2 = Naphth; 4d, R-1 = CH3, R-2 = Ph; 4e, R-1 = CF3, R-2 Ph) have been synthesized and characterized. Molecular structures of 4b and 4e were further confirmed by X-ray crystallographic analysis. Activated with B(C6F5)(3), all the complexes are active for the polymerization of ethylene to branched polyethylenes. Ligand structure, i.e., substituents R-1 and R-2, greatly influences not only catalytic activity but also the molecular weight and branch content of the polyethylene produced. The phenyl-substituted complex 4b exhibits the highest activity of lip to 145 kg PE/mol(Ni)center dot h center dot atm under optimized conditions, which is about 10 times more than unsubstituted complex 4a (14.0 kg PE/mol(Ni center dot)h center dot atm). Highly branched polyethylene with 103 branches per 1000 carbon atoms has been prepared using catalyst 4e.
Resumo:
The dopant/host methodology, which enables efficient tuning of emission color and enhancement of the electroluminescence (EL) efficiency of organic light emitting diodes (OLEDs) based on small molecules, is applied to the design and synthesis of highly efficient green light emitting polymers. Highly efficient green light emitting polymers were obtained by covalently attaching just 0.3-1.0 mol% of a green dopant, 4-(N,N-diphenyl) amino-1,8-naphthaliniide (DPAN), to the pendant chain of polyfluorene (the host). The polymers emit green light and exhibit a high photoluminescence (PL) quantum yield of Lip to 0.96 in solid films, which is attributed to the energy transfer from the polyfluorene host to the DPAN dopant unit. Single layer devices (device configuration: ITO/PEDOT/Polymer/Ca/Al) of the polymers exhibit a turn on voltage of 4.8 V, luminance efficiency of 7.43 cd A(-1), power efficiency of 2.96 lm W-1 and CIE coordinates at (0.26, 0.58). The good device performance can be attributed to the energy transfer and charge trapping from the polyfluorene host to the DPAN dopant unit as well as the molecular dispersion of the dopant in the host.
Resumo:
In amphioxus embryos, the nascent and early mesoderm (including chorda-mesoderm) was visualized by expression of a Brachyury gene (AmBra-2). A band of mesoderm is first detected encircling the earliest (vegetal plate stage) gastrula sub-equatorially. Soon thereafter, the vegetal plate invaginates. resulting in a cap-shaped gastrula with the mesoderm localized at the blastoporal lip and completely encircling the blastopore. As the gastrula stage progresses, DiI (a vital dye) labeling demonstrates that the entire mesoderm is internalized by a slight involution of the epiblast into the hypoblast all around the perimeter of the blastopore. Subsequently. during the early neurula stage, the internalized mesoderm undergoes anterior extension mid-dorsally (as notochord) and dorsolaterally (in paraxial regions when segments will later form). By the late neurula stage, AmBra-2 is no longer transcribed throughout the mesoderm as a whole; instead. expression is detectable only in the posterior mesoderm and in the notochord, but not in par axial mesoderm where definitive somites have formed.
Resumo:
Stable isotope compositions of land snail shells have a great potential as an indicator of paleoclimatic and paleoenvironmental changes. However, some key issues, such as the relationship of carbon isotope between snail food and local vegetation, and the uncertainty of the dominant factors about snail body fluid changes in oxygen isotope composition, remain less well known, strongly limiting shell isotopic application. In this study, we measure the stable isotope compositions on the shells of both live snails and fossils collected from the Chinese Loess Plateau and a loess sequence at Mangshan, Xingyang, respectively. Based on the analyses, the association of the stable isotope compositions of land snail shells with their growing seasons is investigated. In addition, the climatic and environmental significances of isotopic differences among several snail species are discussed. The main results and conclusions are presented as follows: 1. δ18O values for the shell lip samples of Bradybaena ravida redfieldi range from -6.79‰ to -1.92‰, and parallels to the monthly changes of local rain water δ18O, temperature and humidity. The compatibility of shell lip δ18O with monthly modeled shell δ18O indicates that the shell lip δ18O changes are mainly resulted from the 18O variations of rain-water. The shells of a land snail growing in spring could be enriched in 18O, and those growing in summer depleted in 18O. 2. Carbon isotope compositions of snail shells are controlled by their diet, which is affected by the relative proportion of C3 to C4. There are some differences in carbon isotopic compositions among different snail species, especially between P. orphana and V. tenera or P. aeoli. Shell δ13C for P. orphana is the most positive with an average of -5.88 ± 2.54 ‰. The C4 plant fraction of the food for “cold-aridiphilous” taxa, P. aeoli and V. tenera, is distinctly lower than that for “thermo-humidiphilous” taxa, P. orphana, indicating that summer is likely to be the main active season of P. orphana and spring of P. aeoli and V. tenera. Therefore, some discrepancy of carbon isotopic compositions among different species may be related to snail active season. 3. δ13C values among different species have a certain degree of positive correlation, which may be influenced by local vegetation ecosystem. δ13C value of the snail shells (especially P. orphana) shows an eastward increasing trend and consists with the variations of C4 plants biomass in Loess Plateau. The result shows that the carbon isotope in local vegetation ecosystem is one of the main factors influencing δ13C values of snail food. Therefore, both carbon isotopes of local vegetation ecosystem and snail active season contribute to the carbon isotopic differences among different snail species and in different areas. 4. δ13C values of living snail shells and soil organic matter have a positive correlation with each other, which further supports the view that carbon isotope in local vegetation ecosystem is one of the main factors influencing δ13C values of snail food. However, the range of δ13C values of snail food for various species in response to carbon isotope in local vegetation ecosystem is different. It is suggested that 13C enrichment of snail shells relative to local vegetation ecosystem has a potential to indicate snail active season and the degree of climate temperature and humidity. 5. There is a significant negative correlation between carbon and oxygen isotopic compositions of living snail shells in Loess Plateau. This result further supports that snail active season can be inferred based on the shell carbon and oxygen isotopic compositions. Moreover, there are some positive correlations between mean annual temperature and differences of shell δ13C values ( 13CV. tenera-P. orphana) and that of δ18O values ( 18OV. tenera-P. orphana) for P. orphana, a typical “thermo-humidiphilous” taxa, and V. tenera, a typical “cold-aridiphilous” taxa, respectively. It shows that 13CV. tenera-P. orphana and 18OV. tenera-P. orphana may have a potential to indicate mean annual temperature or the length of biological growing season. 6. Stable isotopes of land snail shell in the Mangshan loess sequence show that the shell δ18O value of “cold-aridiphilous” taxa V. tenera is more positive than “thermo-humidiphilous” taxa P. orphana and δ13C value of the former is more negative than the latter. In addition, the shell δ18O value of V. tenera varies significantly in different period. During the last glacial maximum, its δ18O value with an average of -7.89 ‰ is more negative than that (-5.88 ‰) from the last deglaciation to the early Holocene. This phenomenon indicates that its growing season during different period is significantly different. It tends to grow in summer in last glacial maximum. With climate warming, it prefers growing in spring with relatively low temperature. While the shell δ18O value of P. orphana varies in a little range, which shows that its activity season is shorter and mainly in summer. These results further support that the change of the snail growing season is one of the main factors of differences of carbon isotopic compositions among different snail species and varies with time. Furthermore, it is consistent that changes in magnetic susceptibility and trend of differences of shell δ18O values and δ13C values respectively between the two snail fossils. It is further testified that 13CV. tenera-P. orphana and 18OV. tenera-P. orphana may have a potential to indicate mean annual temperature or the length of biological growing season.