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Primary Mode (primary + mode)
Selected AbstractsEffects of eutrophication on bioeroding sponge communities with the description of new West Indian sponges, Cliona spp. (Porifera: Hadromerida: Clionidae)INVERTEBRATE BIOLOGY, Issue 2 2000Katherine E. Holmes Abstract. Pieces of coral rubble (Porites porites), collected from across 3 fringing reefs that lie along a eutrophication gradient, were examined for the presence of clionid sponges. A similarity analysis of species composition showed that reef zone had less effect on clionid community composition than did other factors affecting the reefs as a whole. Except on the back reef, the Zones, distances, and depths within the reefs had no significant influence on the number of clionid invasions. Reef comparisons demonstrated that clionid abundance increased with increasing eutrophication. Clionids were found in 41% of the pieces collected from the most eutrophic site vs. 24% from the least eutrophic. Because clionids are the principal bio-eroders of coral reefs, any increase in their abundance will likely result in greater bioerosion rates. The mean abundance of Type 3 corals (in which fragmentation is the primary mode of propagation) is positively related to the frequency of boring sponge invasion. suggesting that increased bioerosion may be partly responsible for community shifts toward Type 3 corals in polluted waters. Cliona cf. vastifica, found for the first time in Barbados, flourishes on the most eutrophic reef and may become an important bioeroder under the highly eutrophic conditions that have begun to plague West Indian reefs. Two new species of Cliona (Porifera: Hadro-merida: Clionidae) are described. [source] Bioefficacy and mode of action of rocaglamide from Aglaia elaeagnoidea (syn. A. roxburghiana) against gram pod borer, Helicoverpa armigera (Hübner)JOURNAL OF APPLIED ENTOMOLOGY, Issue 3 2004O. Koul Abstract:, Rocaglamide, a highly substituted benzofuran, was isolated and identified as the main biologically active component in Aglaia elaeagnoidea (syn. A. roxburghiana) for gram pod borer Helicoverpa armigera (Hübner). Addition of rocaglamide to an artificial diet retarded the growth of neonate larvae in a dose-dependent manner with EC50 values of 0.76 p.p.m. These values compared favourably with azadirachtin (EC50 = 0.23 p.p.m.). However, azadirachtin was apparently more potent than rocaglamide in inducing growth inhibition via oral administration to these first stadium larvae. The candidate compound was found to have LD50 and LD95 values of 0.40 and 1.02 ,g per larva, respectively, in topical application against third instar larvae 96 h post-treatment. However, these values for azadirachtin were 8.16 and 25.8 ,g per larva for the same period. This shows that azadirachtin was less effective against third instar H. armigera larvae in inducing acute toxicity via topical treatment in comparison with rocaglamide. However, severe morphological larval deformities were observed in such azadirachtin-treated larvae during the process of ecdysis. The cytotoxic nature of rocaglamide was established by evaluating dietary utilization and the results did not implicate any antifeedant effect but the toxicity-mediated effect due to reduced efficiency of conversion of ingested food. It was obvious that feeding deterrence is not the primary mode of action but a centrally mediated effect, which could be due to the induced cytotoxicity at non-specific cellular levels. [source] Utilization of inorganic carbon in the edible cyanobacterium Ge-Xian-Mi (Nostoc) and its role in alleviating photo-inhibitionPLANT CELL & ENVIRONMENT, Issue 12 2004B. S. QIU ABSTRACT The present work investigated the inorganic carbon (Ci) uptake, fluorescence quenching and photo-inhibition of the edible cyanobacterium Ge-Xian-Mi (Nostoc) to obtain an insight into the role of CO2 concentrating mechanism (CCM) operation in alleviating photo-inhibition. Ge-Xian-Mi used HCO3, in addition to CO2 for its photosynthesis and oxygen evolution was greater than the theoretical rates of CO2 production derived from uncatalysed dehydration of HCO3,. Multiple transporters for CO2 and HCO3, operated in air-grown Ge-Xian-Mi. Na+ -dependent HCO3, transport was the primary mode of active Ci uptake and contributed 53,62% of net photosynthetic activity at 250 µmol L,1 KHCO3 and pH 8.0. However, the CO2 -uptake systems and Na+ -independent HCO3, transport played minor roles in Ge-Xian-Mi and supported, respectively, 39 and 8% of net photosynthetic activity. The steady-state fluorescence decreased and the photochemical quenching increased in response to the transport-mediated accumulation of intracellular Ci. Inorganic carbon transport was a major factor in facilitating quenching during the initial stage and the initial rate of fluorescence quenching in the presence of iodoacetamide, an inhibitor of CO2 fixation, was 88% of control. Both the initial rate and extent of fluorescence quenching increased with increasing external dissolved inorganic carbon (DIC) and saturated at higher than 200 µmol L,1 HCO3,. The operation of the CCM in Ge-Xian-Mi served as a means of diminishing photodynamic damage by dissipating excess light energy and higher external DIC in the range of 100,10000 µmol L,1 KHCO3 was associated with more severe photo-inhibition under strong irradiance. [source] The governance of urban regeneration: a critique of the ,governing without government' thesisPUBLIC ADMINISTRATION, Issue 2 2002Jonathan S. DaviesArticle first published online: 17 DEC 200 This paper offers a critique of the concept of governance as networks. Using the complementary concept of regime governance, it argues that networks are not the primary mode of governance in the politics of urban regeneration in the UK. Drawing on primary and secondary material, it is argued that Central Government is becoming more influential in the local policy arena. In the ,mix' of market, hierarchy and network, hierarchy is more pervasive than network. It is therefore argued that partnerships should be treated as a distinct mode of governance. These conclusions demonstrate that despite the fashion for copying urban policies from the USA, local politics in the UK remain very different. Ironically, the transfer of policies developed in the USA has tended to entrench divergent practices and outcomes. The UK does not, therefore, appear to be moving toward the US model of regime politics. It is concluded that the partnership and network/regime models of governance should be subjected to rigorous comparative studies. [source] Morphogenesis of the Marine Ciliate, Pseudoamphisiella alveolata (Kahl, 1932) Song & Warren, 2000 (Ciliophora, Stichotrichia, Urostylida) During Binary FissionTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 5 2006CHEN SHAO ABSTRACT. Morphogenesis during the binary fission of the stichotrich ciliate Pseudoamphisiella alveolata, isolated from Jiaozhou Bay near Qingdao, China, was investigated using protargol silver impregnation. The process is characterized as follows: (1) in the proter, only the posterior part of the parental adoral zone of membranelles is renewed, where the membranelles dedifferentiate and then rebuild the UM-anlage and the missing membranelles, (2) the oral primordium in the opisthe and the FVT-anlagen in both dividers are formed de novo on the cell surface, (3) an "extra" anlage, which is generated on the right of the right marginal anlage, develops into three or four "extra" marginal cirri that connect the caudal cirri with the marginal rows, (4) the right marginal anlage is formed within the old structure, (5) the FVT-cirri develop in a primary mode, and (6) unlike most stichotrichs, the right marginal anlagen in both dividers generate closely together. As an additional contribution, the diversity of morphogenetic patterns within the genus Pseudoamphisiella is discussed. Based on both morphogenetic and SS rRNA gene sequencing data, the systematic position of the genus Pseudoamphisiella as well as the family Pseudoamphisiellidae Song et al. 1997 is briefly analyzed. The results indicate that they should very possibly represent a higher evolved group in the order Urostylida. [source] Metastatic Renal Cell Carcinoma to the Head and Neck,THE LARYNGOSCOPE, Issue 9 2002Keith M. Pritchyk MD Abstract Objectives The objectives of the study were to present four cases of renal cell carcinoma (RCC) metastatic to the head and neck, to recognize the appearance on radiographic studies, to understand the importance of preoperative embolization, and to review the results of treatment. Study Design Retrospective review of patients diagnosed with metastatic RCC to the head and neck. Methods The records of four patients diagnosed with metastatic RCC at a tertiary medical center over a 5-year period from 1996 to 2001 were reviewed and analyzed for demographic and outcomes data. Results Metastatic RCC to the head and neck was seen in the following locations: nasal cavity, lower lip, hard palate, tongue, and maxillary sinus. Presenting signs were loose upper molars, dysphagia, nasal obstruction, lower lip lesion, recurrent epistaxis, and foul nasal drainage. Histological studies confirmed metastasis of RCC in all four patients. Treatment consisted of preoperative radiation therapy, embolization, and local excision with adjunct chemotherapy. Conclusions Metastatic RCC to the head and neck is rare but can have serious consequences if not recognized before biopsy. We present several treatment options with local excision as the primary mode of treatment. [source] Interspecific Competition and Niche Separation in Primates: A Global AnalysisBIOTROPICA, Issue 3 2009Brian M. Schreier ABSTRACT Primates are an extraordinarily well-known tropical forest, mammalian taxon. We investigated potential modes of niche separation in primates by identifying sympatric species with putatively similar niche characteristics and assessing potential competition using data gleaned from an extensive literature review. We defined competing species-pairs as (a) sympatric species in which (b) the body mass of the larger species was within 30 percent of the smaller species' mass and (c) the species had the same category of diet. A sample of 43 well-studied forests (7,20 per continent) provided 673 pairs of sympatric primate species. Of these, 45 pairs (7%) are potential competitors by our definition. Africa has the largest number of competing pairs (17 pairs), while Asia might have the highest percentage of competitors in each forest site (17%). Niche separation was investigated for each pair by examining them for each of eight possible modes of separation: detailed differences in diets (28% of potential competitors), use of different heights in the forest (25%), use of different types of forest (14%), use of different locations within the forest (11%), use of support branches of different diameters (7%), different ranging behavior (6%), different techniques of prey capture (4%), and differential timing of activity (4%). The use of different heights in the forest is the dominant form of potential separation in Africa (31% of competing species-pairs) and Asia (38%), while detailed differences in diet appears to be the primary mode of niche separation in the Americas (26%) and Madagascar (32%). [source] Multidecadal climate variability of global lands and oceansINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 7 2006Gregory J. McCabe Abstract Principal components analysis (PCA) and singular value decomposition (SVD) are used to identify the primary modes of decadal and multidecadal variability in annual global Palmer Drought Severity Index (PDSI) values and sea-surface temperatures (SSTs). The PDSI and SST data for 1925,2003 were detrended and smoothed (with a 10-year moving average) to isolate the decadal and multidecadal variability. The first two principal components (PCs) of the PDSI PCA explained almost 38% of the decadal and multidecadal variance in the detrended and smoothed global annual PDSI data. The first two PCs of detrended and smoothed global annual SSTs explained nearly 56% of the decadal variability in global SSTs. The PDSI PCs and the SST PCs are directly correlated in a pairwise fashion. The first PDSI and SST PCs reflect variability of the detrended and smoothed annual Pacific Decadal Oscillation (PDO), as well as detrended and smoothed annual Indian Ocean SSTs. The second set of PCs is strongly associated with the Atlantic Multidecadal Oscillation (AMO). The SVD analysis of the cross-covariance of the PDSI and SST data confirmed the close link between the PDSI and SST modes of decadal and multidecadal variation and provided a verification of the PCA results. These findings indicate that the major modes of multidecadal variations in SSTs and land-surface climate conditions are highly interrelated through a small number of spatially complex but slowly varying teleconnections. Therefore, these relations may be adaptable to providing improved baseline conditions for seasonal climate forecasting. Copyright © 2006 John Wiley & Sons, Ltd. [source] Two major modes of variability of the East Asian summer monsoonTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 649 2010Xuguang Sun Abstract We study the two primary modes of variability associated with the East Asian summer monsoon, as identified using a multivariate Empirical Orthogonal Function (EOF) analysis. The second mode is shown to be related to changes in intensity of the South Asian High at 100 hPa while, consistent with previous work, the first mode is associated with an index for the shear vorticity of the 850 hPa zonal wind over the monsoon region. We show that a linear, dry dynamical model, when driven by the diabatic heating anomalies associated with each mode, can reproduce many of the anomalous circulation features, especially for the first EOF and in the lower troposphere. The model results indicate the importance of diabatic heating anomalies over the tropical Indian Ocean in the dynamics of both modes, especially EOF-1, and illustrate the role of local diabatic feedback for intensifying the circulation anomalies; in particular, the subtropical anticyclonic anomalies that are found in the positive phase of both modes, and the circulation anomaly associated with the Meiyu/Changma/Baiu rain band. A running cross-correlation analysis shows that the second EOF is consistently linked to both the decaying and the onset phase of El Nińo/Southern Oscillation (ENSO) events throughout the study period (1958,2001). We attribute the connection in the onset phase to zonal wind anomalies along the Equator in the west Pacific associated with this mode. On the other hand, a link between the first EOF and ENSO is found only in the post-1979 period. We note also the role of sea-surface temperature anomalies in the tropical Indian Ocean in the dynamics of EOF-1, and a link to the variability of the Indian summer monsoon in the case of EOF-2. Copyright © 2010 Royal Meteorological Society [source] | |||||||||||||