Phytochemical screening, antioxidant and cytotoxic activity of fruit extracts of Calamus tenuis Roxb

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Zaki Uddin Ahmed

2014-08-01

Full Text Available Objective: To investigate the antioxidant and cytotoxic activity of the fruits of Calamus tenuis Roxb. Methods: The preliminary phytochemical group tests were done, which revealed the presence of alkaloid, tannin, flavonoid and steroid. The dried fruit was extracted in soxhlet apparatus using petroleum ether, ethyl acetate and methanol. Antioxidant potential of each extract was evaluated using total phenol content, total flavonoid content, cupric reducing antioxidant capacity, 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, and total antioxidant capacity determinations. Results: The extracts were found to possess moderate to high amounts of phenolic and flavonoid contents. In cupric reducing antioxidant capacity assay the extracts showed moderate reducing power which increases with concentration. Scavenging of 1,1-diphenyl-2-picrylhydrazyl radical was found to rise with concentration with lowest IC50 value for methanol extract, which was confirmed by total antioxidant activity test that shows highest (95 mg/g of extract in ascorbic acid equivalent for methanol extract. In Brine shrimp lethality bioassay the methanol and petroleum ether extracts were found to be toxic to Brine shrimp nauplii, with LC50 of 25.53 µg/mL and 28.07 µg/mL respectively while the LC50 of the reference vincristine sulphate was 1.32 µg/mL. Ethyl acetate extract was found to be moderately cytotoxic showing LC50 of 47.79 µg/mL. Conclusions: The results of the present study suggest that the fruits of Calamus tenuis Roxb possess antioxidant and cytotoxic potential. Moreover, phytochemical screening reveals the presence of alkaloid, tannin, flavonoid and steroid, which may be responsible for the observed bioactivities.

Inhibition of spore germination of Alternaria tenuis by sulfur dioxide

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Couey, H.M.

1962-08-01

As a part of a continuing study of SO/sub 2/ fumigation of table grapes, the effect of SO/sub 2/ on spores of an isolate of A. tenuis Auct. causing decay of table grapes was determined. The amount of SO/sub 2/ required to inhibit completely spore germination depended on availability of moisture and the temperature. At 20/sup 0/C, wet spores required 20-min exposure to 100 ppm SO/sub 2/ to prevent germination, but spores equilibrated at 90% relative humidity (RH) required 10-min exposure to 1000 ppm SO/sub 2/. Dry spores at 60% RH were unaffected by a 20-min exposure to 4000 ppm SO/sub 2/. Increasing the temperature in the range 5-20/sup 0/C increased effectiveness of the SO/sub 2/ treatment. A comparison of Alternaria with Botrytis cinerea Fr. (studied earlier) showed that wet spores of these organisms were about equally sensitive to SO/sub 2/, but that dry Alternaria spores were more resistant to SO/sub 2/ than dry Botrytis spores under comparable conditions.

Doğal florada yetişen sarıçiçekli gazal boynuzu (Lotus corniculatus L. ve dar yapraklı gazal boynuzunun (Lotus tenuis Waldst. & Kit. toprak tercihleri, komşu bitkileri ve yem değerleri

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Ferat Uzun

2018-02-01

Full Text Available In this study, soil preferences of wild birdsfoot trefoil (Lotus corniculatus L. and narrowleaf birdsfoot trefoil (L tenuis Waldst. & Kit. species growing in natural flora of the Black Sea Region (Turkey and the plant species which they interact with, as well as their feed values were investigated. Dominant forage species that interact with L. corniculatus and L. tenuis were determined by the visual estimation method at 126 and 86 locations, respectively, and also seed and soil samples from each location were collected. L. corniculatus preferred soils having higher lime (90.9 vs. 66.4 g kg-1, P=0.003, pH (7.41 vs. 7.14, P=0.001 and containing lower organic matter (20.0 vs. 26.8 g kg-1, P=0.001 compared to L. tenuis. L. corniculatus was neighbor to 89 different species (20.2% legume, 22.5% grass and 57.3% others, whereas L. tenuis was neighbor to 61 different species (41.0% legume, 19.7% grass and 39.3% others. The difference between two species in terms of the frequencies of neighbor plant families was significant (2=10.814, P=0.004. Dominant plant species growing in interaction with these Lotus species were Medicago lupulina, Trifolium pratense, Trifolium repens, Cynodon dactylon, Lolium perenne and Plantago lanceolata. Dactylis glomerata was also neighbor with high frequency to L. corniculatus. L. tenuis had high phosphorus, metabolizable energy and relative feed value, and lower acid and neutral detergent fiber contents. As a result, in the artificial pasture establishments or the improvement of natural rangelands, the aforementioned species growing in harmony in natural environment and exhibiting positive interaction with Lotus species studied should be preferred.

Effects of coal contamination on early life history processes of a reef-building coral, Acropora tenuis.

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Berry, Kathryn L E; Hoogenboom, Mia O; Brinkman, Diane L; Burns, Kathryn A; Negri, Andrew P

2017-01-15

Successful reproduction and larval dispersal are important for the persistence of marine invertebrate populations, and these early life history processes can be sensitive to marine pollution. Coal is emerging as a contaminant of interest due to the proximity of ports and shipping lanes to coral reefs. To assess the potential hazard of this contaminant, gametes, newly developed embryos, larvae and juveniles of the coral Acropora tenuis were exposed to a range of coal leachate, suspended coal, and coal smothering treatments. Fertilisation was the most sensitive reproductive process tested. Embryo survivorship decreased with increasing suspended coal concentrations and exposure duration, effects on larval settlement varied between treatments, while effects on juvenile survivorship were minimal. Leachate exposures had negligible effects on fertilisation and larval settlement. These results indicate that coral recruitment could be affected by spills that produce plumes of suspended coal particles which interact with gametes and embryos soon after spawning. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Heavy metal tolerance in populations of Agrostis tenuis Sibth and other grasses

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Gregory, R P.G.; Bradshaw, A D

1965-01-01

Populations of Agrostis tenuis can be found growing on a variety of different mine workings in conditions of metal contamination toxic to most higher plants. Samples of such populations together with samples of populations taken from ordinary pastures were tested for tolerance to high concentrations of copper, nickel, lead and zinc by measuring the effect of these metals on the rooting of tillers. The soils in which the populations were originally growing were analyzed for each of the four metals and the tolerances of the populations have been related to the levels of the metals in the soils. In general, the mine populations show remarkable tolerance to the particular metals present in high quantities in the soils of their original habitats: the pasture populations do not show this tolerance. The tolerance is specific, for, except in the case of zinc and nickel, tolerance to one metal is not accompanied by tolerance to any other. There must, therefore, be three specific tolerances in the one species. Individual tolerances can however occur together and this can be related to the occurrence of the two metals together in toxic quantities in the soil. The tolerances must be genetically controlled but the physiological mechanism involved is not clear. A number of other species were also shown to have populations tolerant to high levels of zinc. 27 references, 7 figures, 6 tables.

Distribution of zinc-65 in Agrostis tenuis Sibth. and A. stolonifera L. tissues

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Peterson, P J

1969-11-01

The distribution of /sup 65/Zn in zinc-tolerant and copper-tolerant plants of Agrotis spp. from toxic mine-tailings in England and Wales was compared with zinc distribution in non-tolerant plants. Isotope was applied in culture solution in which the plants were growing. No differences could be demonstrated between the plants by whole-plant radioautography, or by zinc analyses of the tops. Root/shoot ratios calculated from specific activity values varied with population, the non-tolerant plants having the lowest and the zinc-tolerant plants the highest ratio. After solvent (80% ethanol and water) extractions, the root residue of zinc-tolerant plants contained a higher percentage of /sup 65/Zn than that of non-tolerant plants. Chemical fractionation of the roots revealed that the main difference was that the amount of /sup 65/Zn in the pectate extract of the cell wall was high in zinc-tolerant plants and low in non-tolerant plants. The /sup 65/Zn distribution in the copper-tolerant plants was similar to that in the non-tolerant plants, indicating that the tolerance mechanisms for the two elements are different. Soluble protein and RNA preparations were made but they contained low levels of /sup 65/Zn. An exception was the relatively high value for RNA from zinc-tolerant A. stolonifera shoots. An anionic complex of /sup 65/Zn in the soluble fraction was investigated. This complex accounted for most of the radioactivity in A. tenuis extracts of shoots but the concentration of the complex was low in A. stolonifera shoots, and in root extracts of all plants examined. 18 references, 2 figures, 4 tables.

Intraspecific variation in a physiological thermoregulatory mechanism: the case of the lizard Liolaemus tenuis (Liolaeminae Variación intraespecífica en un mecanismo termorregulatorio fisiológico: el caso del lagarto Liolaemus tenuis (Liolaeminae

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MARCELA A VIDAL

2008-06-01

Full Text Available The interspecific variation of heating rates in Liolaemus lizards, suggests an adaptive value of this physiological thermoregulatory mechanism, which would allow lizards to cope with the environmental thermal restrictions, imposed to behavioral thermoregulation. This trend has barely been tested at intraspecific level, and here we explore if intraspecific variation in heating rates occurs in Liolaemus tenuis, a relative widely distributed species from central Chile. We test the hypothesis that heating rates are related to the thermal environmental conditions at which populations are exposed, by comparing the heating rates of three populations (from a latitudinal range, which inhabit under different thermal conditions. Additionally, we explore if the intrinsic factor, sex, also modulates heating rates. There was a significant intraspecific variation in heating rates, at population and gender level. These rates however, showed only a partial relationship with the environmental thermal conditions. We found that the northern population, inhabiting at higher temperature, heated slower, which might reduce the risk of overheating. On the other hand, independent of the population, females heated slower than males. The meaning of this sexual variation is unclear, but may be consequence of the significant differences in genders' social behavior. Because males defend a territory with a harem, by heating faster, they can allocate extra time in behaviors associated to the defense and maintenance of the territory.La variación interespecífica en las tasas de calentamiento de Liolaemus pareciera ser un mecanismo fisiológico adaptativo que permitiría a los lagartos enfrentar restricciones térmicas ambientales impuestas a la termorregulación conductual. Esta tendencia ha sido raramente analizada a nivel intraespecífico y en este estudio exploramos si existe variación intraespecífica en las tasas de calentamiento de Liolaemus tenuis, una especie con rango

Variation in the health and biochemical condition of the coral Acropora tenuis along two water quality gradients on the Great Barrier Reef, Australia.

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Rocker, Melissa M; Francis, David S; Fabricius, Katharina E; Willis, Bette L; Bay, Line K

2017-06-30

This study explores how plasticity in biochemical attributes, used as indicators of health and condition, enables the coral Acropora tenuis to respond to differing water quality regimes in inshore regions of the Great Barrier Reef. Health attributes were monitored along a strong and weak water quality gradient, each with three reefs at increasing distances from a major river source. Attributes differed significantly only along the strong gradient; corals grew fastest, had the least dense skeletons, highest symbiont densities and highest lipid concentrations closest to the river mouth, where water quality was poorest. High nutrient and particulate loads were only detrimental to skeletal density, which decreased as linear extension increased, highlighting a trade-off. Our study underscores the importance of assessing multiple health attributes in coral reef monitoring. For example, autotrophic indices are poor indicators of coral health and condition, but improve when combined with attributes like lipid content and biomass. Copyright © 2017 Elsevier Ltd. All rights reserved.

Systematic strain construction and process development: Xylitol production by Saccharomyces cerevisiae expressing Candida tenuis xylose reductase in wild-type or mutant form.

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Pratter, S M; Eixelsberger, T; Nidetzky, B

2015-12-01

A novel Saccharomyces cerevisiae whole-cell biocatalyst for xylitol production based on Candida tenuis xylose reductase (CtXR) is presented. Six recombinant strains expressing wild-type CtXR or an NADH-specific mutant were constructed and evaluated regarding effects of expression mode, promoter strength, biocatalyst concentration and medium composition. Intracellular XR activities ranged from 0.09 U mgProt(-1) to 1.05 U mgProt(-1) but did not correlate with the strains' xylitol productivities, indicating that other factors limited xylose conversion in the high-activity strains. The CtXR mutant decreased the biocatalyst's performance, suggesting use of the NADPH-preferring wild-type enzyme when (semi-)aerobic conditions are applied. In a bioreactor process, the best-performing strain converted 40 g L(-1) xylose with an initial productivity of 1.16 g L(-1)h(-1) and a xylitol yield of 100%. The obtained results underline the potential of CtXR wild-type for xylose reduction and point out parameters to improve "green" xylitol production. Copyright © 2015 Elsevier Ltd. All rights reserved.

The structure of apo and holo forms of xylose reductase, a dimeric aldo-keto reductase from Candida tenuis.

Science.gov (United States)

Kavanagh, Kathryn L; Klimacek, Mario; Nidetzky, Bernd; Wilson, David K

2002-07-16

Xylose reductase is a homodimeric oxidoreductase dependent on NADPH or NADH and belongs to the largely monomeric aldo-keto reductase superfamily of proteins. It catalyzes the first step in the assimilation of xylose, an aldose found to be a major constituent monosaccharide of renewable plant hemicellulosic material, into yeast metabolic pathways. It does this by reducing open chain xylose to xylitol, which is reoxidized to xylulose by xylitol dehydrogenase and metabolically integrated via the pentose phosphate pathway. No structure has yet been determined for a xylose reductase, a dimeric aldo-keto reductase or a family 2 aldo-keto reductase. The structures of the Candida tenuis xylose reductase apo- and holoenzyme, which crystallize in spacegroup C2 with different unit cells, have been determined to 2.2 A resolution and an R-factor of 17.9 and 20.8%, respectively. Residues responsible for mediating the novel dimeric interface include Asp-178, Arg-181, Lys-202, Phe-206, Trp-313, and Pro-319. Alignments with other superfamily members indicate that these interactions are conserved in other dimeric xylose reductases but not throughout the remainder of the oligomeric aldo-keto reductases, predicting alternate modes of oligomerization for other families. An arrangement of side chains in a catalytic triad shows that Tyr-52 has a conserved function as a general acid. The loop that folds over the NAD(P)H cosubstrate is disordered in the apo form but becomes ordered upon cosubstrate binding. A slow conformational isomerization of this loop probably accounts for the observed rate-limiting step involving release of cosubstrate. Xylose binding (K(m) = 87 mM) is mediated by interactions with a binding pocket that is more polar than a typical aldo-keto reductase. Modeling of xylose into the active site of the holoenzyme using ordered waters as a guide for sugar hydroxyls suggests a convincing mode of substrate binding.

COMPOSICIÓN QUIMICA Y ACTIVIDAD ANTIFOULING DE LA FRACCION LIPIDICA DE LA ESPONJA MARINA Cliona tenuis (Clionidae

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Leonardo Castellanos

2009-04-01

Full Text Available Normal 0 21 false false false st1\\:*{behavior:url(#ieooui } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Del extracto orgánico de la esponja marina Cliona tenuis, recolectada en las Islas del Rosario (Colombia, Mar Caribe, fue obtenida la fracción lipídica, la cual presentó propiedades antifouling en pruebas en campo. Esta fracción fue separada por CC sobre gel de sílice hasta obtener fracciones de ésteres metílicos, glicéridos, glicolípidos, fosfolípidos y ácidos grasos libres, las cuales fueron identificadas por CCD y técnicas de dereplicación (RMN 1H y 13C. Posteriormente, las fracciones de glicéridos, glicolípidos y fosfolípidos fueron hidrolizadas y los ácidos obtenidos, junto con los provenientes de la fracción de ácidos grasos libres, fueron transformados en ésteres metílicos y todos se analizaron por CGAR-EM. Para ubicar las insaturaciones y ramificaciones, los ésteres metílicos se transformaron luego en sus correspondientes pirrolididas, las cuales también se analizaron por CGAR-EM. El estudio cromatográfico (valores de ECL y de los espectros de masas de los ésteres metílicos y de sus derivados pirrolididas permitió identificar 81 ácidos grasos diferentes, de los cuales no habían sido previamente reportados: los ácidos 4,8-hexadecadienoico, 11-metil-4,10-octadecadienoico, 6,9,12,14-icosatetraenoico, y 6,9,12,14,17-icosapentanoico.

Cumulative Effects of Nutrient Enrichment and Elevated Temperature Compromise the Early Life History Stages of the Coral Acropora tenuis

Science.gov (United States)

Noonan, Sam H. C.; Willis, Bette L.; Fabricius, Katharina E.; Negri, Andrew P.

2016-01-01

Inshore coral reefs are experiencing the combined pressures of excess nutrient availability associated with coastal activities and warming seawater temperatures. Both pressures are known to have detrimental effects on the early life history stages of hard corals, but studies of their combined effects on early demographic stages are lacking. We conducted a series of experiments to test the combined effects of nutrient enrichment (three levels) and elevated seawater temperature (up to five levels) on early life history stages of the inshore coral Acropora tenuis, a common species in the Indo-Pacific and Red Sea. Gamete fertilization, larval survivorship and larval settlement were all significantly reduced as temperature increased, but only fertilization was further affected by simultaneous nutrient enrichment. Combined high temperatures and nutrient enrichment affected fertilization in an additive manner, whereas embryo abnormalities increased synergistically. Higher than normal temperatures (32°C) increased coral juvenile growth rates 1.6-fold, but mortality also increased by 50%. The co-occurrence of nutrient enrichment with high temperatures reduced juvenile mortality to 36%, ameliorating temperature stress (antagonistic interaction). Overall, the types of effect (additive vs synergistic or antagonistic) and their magnitude varied among life stages. Gamete and embryo stages were more affected by temperature stress and, in some cases, also by nutrient enrichment than juveniles. The data suggest that coastal runoff events might exacerbate the impacts of warming temperatures on fertilization if these events co-occur during corals spawning. The cumulative impacts of simultaneous exposure to nutrient enrichment and elevated temperatures over all early life history stages increases the likelihood for failure of larval supply and recruitment for this coral species. Our results suggest that improving the water quality of river discharges into coastal areas might help to

Cumulative Effects of Nutrient Enrichment and Elevated Temperature Compromise the Early Life History Stages of the Coral Acropora tenuis.

Science.gov (United States)

Humanes, Adriana; Noonan, Sam H C; Willis, Bette L; Fabricius, Katharina E; Negri, Andrew P

2016-01-01

Inshore coral reefs are experiencing the combined pressures of excess nutrient availability associated with coastal activities and warming seawater temperatures. Both pressures are known to have detrimental effects on the early life history stages of hard corals, but studies of their combined effects on early demographic stages are lacking. We conducted a series of experiments to test the combined effects of nutrient enrichment (three levels) and elevated seawater temperature (up to five levels) on early life history stages of the inshore coral Acropora tenuis, a common species in the Indo-Pacific and Red Sea. Gamete fertilization, larval survivorship and larval settlement were all significantly reduced as temperature increased, but only fertilization was further affected by simultaneous nutrient enrichment. Combined high temperatures and nutrient enrichment affected fertilization in an additive manner, whereas embryo abnormalities increased synergistically. Higher than normal temperatures (32°C) increased coral juvenile growth rates 1.6-fold, but mortality also increased by 50%. The co-occurrence of nutrient enrichment with high temperatures reduced juvenile mortality to 36%, ameliorating temperature stress (antagonistic interaction). Overall, the types of effect (additive vs synergistic or antagonistic) and their magnitude varied among life stages. Gamete and embryo stages were more affected by temperature stress and, in some cases, also by nutrient enrichment than juveniles. The data suggest that coastal runoff events might exacerbate the impacts of warming temperatures on fertilization if these events co-occur during corals spawning. The cumulative impacts of simultaneous exposure to nutrient enrichment and elevated temperatures over all early life history stages increases the likelihood for failure of larval supply and recruitment for this coral species. Our results suggest that improving the water quality of river discharges into coastal areas might help to

Control of the Tomato Leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), in Open-Field Tomatoes by Indigenous Natural Enemies Occurring in Israel.

Science.gov (United States)

Shaltiel-Harpaz, Liora; Gerling, Dan; Graph, Shaul; Kedoshim, Hendrika; Azolay, Lotem; Rozenberg, Tamir; Nachache, Yaakov; Steinberg, Shimon; Allouche, Arnon; Alon, Tamar

2016-02-01

The tomato leafminer, Tuta absoluta (Meyrick), had established in Israel by 2010, attacking both open-field tomatoes and greenhouse crops.We searched for its natural enemies in open-field tomatoes, and tried to determine their potential for controlling this pest. We surveyed the local natural enemies in open tomato fields and measured their impact on pest populations in an unsprayed field. We assessed the suppressive ability of the dominant hemipteran predator, Nesidiocoris tenuis Reuter, against T. absoluta under controlled laboratory conditions and evaluated the impact of its augmentation on T. absoluta control in open-field tomatoes. We found five natural enemy species:the predator, N. tenuis, two braconids, and two eulophids. Predation accounted for 64.5±9.2% (mean ± SE) of T. absoluta larval mortality, whereas parasitism accounted for 20.96±7.5%. Together, they eliminated the pest population at tomato harvest time. Under controlled conditions, predation by N. tenuis rose from 58 to 72% with increased density of T. absoluta, suggesting positive density dependence. The reduction of T. absoluta (83%) by N. tenuis was higher than that of Bemisia tabaci (32%), suggesting a preference of N. tenuis for T. absoluta. Augmentation of N.tenuis was as effective as conventional treatment insecticide treatment, and plant damage was low and did not seem to affect yield. Results indicate that reduced pesticide use enables indigenous natural enemies, particularly N.tenuis, to successfully control T. absoluta and prevent crop damage in open-field tomatoes.

Spatiotemporal mapping of the muscular activity of the gizzard of the chicken (Gallus domesticus).

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Lentle, R G; Reynolds, G; de Loubens, C; Hulls, C; Janssen, P W M; Ravindran, V

2013-02-01

We report the results of spatiotemporal mapping of the spontaneous actions of component muscles of the gizzard and associated structures in ex vivo preparations with combined superfusion and vascular perfusion. Ongoing spontaneous contraction of cranial and caudal thin muscles occurred at a frequency of 2.2 ± 0.1 cycles per minute. Contractions of M. tenuis craniodorsalis with mean duration of 2.8 ± 0.2 s commenced ventrally adjacent to the distal limit of the proventriculus and progressed dorsally at 2.02 ± 0.03 mm•s(-1) in a concerted front. Near simultaneous contraction of M. tenuis caudoventralis of mean duration of contraction of 4.7 ± 0.7 s commenced dorsally and progressed ventrally at a similar rate (2.1 ± 0.1 mm•s(-1)) and in a similar manner. Contraction of the caudoventralis preceded that of craniodorsalis (mean 1.1 ± 0.15 s). Contraction of the 2 tenuis muscles was synchronous with the first component peak of the cyclic increase in lumen pressure and with distension of the crassus musculature. Contraction of the M. crassus caudodorsalis muscle coincided with the second component peak and was followed by distension of the tenuis musculature. The latter commenced before the relaxation of the tenuis muscles. Contractions of the crassus muscle propagated rapidly at right angles to the orientation of the muscle fibers at a faster velocity than that of the tenuis musculature. The durations of the component peaks in lumen pressure indicated that the duration of crassus contraction was similar to that of the tenuis musculature.

Analysis of the complete plastomes of three species of Membranoptera (Ceramiales, Rhodophyta) from Pacific North America.

Science.gov (United States)

Hughey, Jeffery R; Hommersand, Max H; Gabrielson, Paul W; Miller, Kathy Ann; Fuller, Timothy

2017-02-01

Next generation sequence data were generated and used to assemble the complete plastomes of the holotype of Membranoptera weeksiae, the neotype (designated here) of M. tenuis, and a specimen examined by Kylin in making the new combination M. platyphylla. The three plastomes were similar in gene content and length and showed high gene synteny to Calliarthron, Grateloupia, Sporolithon, and Vertebrata. Sequence variation in the plastome coding regions were 0.89% between M. weeksiae and M. tenuis, 5.14% between M. weeksiae and M. platyphylla, and 5.18% between M. tenuis and M. platyphylla. We were unable to decipher the complete mitogenomes of the three species due to low coverage and structural problems; however, we assembled and analyzed, the cytochrome oxidase I, II, and III loci and found that M. weeksiae and M. tenuis differed in sequence by 1.3%, M. weeksiae and M. platyphylla by 8.4%, and M. tenuis and M. platyphylla by 8.1%. Evaluation of standard marker genes indicated that sequences from the rbcL, RuBisCO spacer, and CO1 genes closely approximated the pair-wise genetic distances observed between the plastomes of the three species of Membranoptera. A phylogenetic tree based on rbcL sequences showed that M. tenuis and M. weeksiae were sister taxa. Short rbcL sequences were obtained from type specimens of M. dimorpha, M. multiramosa, and M. edentata and confirmed their conspecificity with M. platyphylla. The data support the recognition of three species of Membranoptera occurring south of Alaska: M. platyphylla, M. tenuis, and M. weeksiae. © 2016 Phycological Society of America.

Effects of alumina refinery wastewater and signature metal constituents at the upper thermal tolerance of: 2. The early life stages of the coral Acropora tenuis

International Nuclear Information System (INIS)

Negri, Andrew P.; Harford, Andrew J.; Parry, David L.; Dam, Rick A. van

2011-01-01

Research highlights: →Methodology to assess relevant toxicants to sensitive early life histories of coral. → Explored the thermal sensitivity of fertilisation and larval metamorphosis in a coral. → First study to identify IC 50 s for Al, Ga and V in corals (at summer temperature). → First study to test the effects of an alumina outfall wastewater on coral. → Found additive effects of wastewater and high SST on fertilisation and metamorphosis. - Abstract: The success of early life history transitions of the coral Acropora tenuis were used as endpoints to evaluate thermal stress and the effects of wastewater discharged to a tropical marine environment. The studies assessed the effects of: (i) temperature; (ii) three signature metals of the wastewater, aluminium (Al), vanadium (V) and gallium (Ga); and (iii) the wastewater (at 27 o C and 32 o C) on fertilisation and larval metamorphosis. The median inhibition temperatures for fertilisation and metamorphosis were 32.8 o C and 33.0 o C, respectively. Fertilisation IC 50 s for Al, V and Ga were 2997, 2884 and 3430 μg L -1 , respectively. Metamorphosis IC 50 s for Al, V and Ga were 1945, 675 and 3566 μg L -1 , respectively. The wastewater only affected fertilisation and metamorphosis at moderate concentrations (IC 50 s = 63% and 67%, v/v, respectively, at 27 o C), posing a low risk to this species in the field. The effects of wastewater and temperature on fertilisation and metamorphosis were additive.

Combined effect of sulfur dioxide and carbon dioxide gases on mold fungi

Energy Technology Data Exchange (ETDEWEB)

Kochurova, A.I.; Karpova, T.N.

1974-01-01

Sulfur dioxide at 0.08% killed Penicillium expansum, Stemphylium macrosporium, and Botrytis cinerea within 24 hours. At 0.2%, it killed P. citrinum, Alternaria tenuis, and Fusarium moniliforme. Sulfur dioxide (at 0.04%) and Sulfur dioxide-carbon dioxide mixtures (at 0.02 and 5% respectively) completely suppressed the growth of P. citrinum, P. expansum, P. rubrum, A. tenuis, S. macrosporium, B. cinerea, and F. moniliforme in laboratory experiments. 1 table.

The role of parasite-driven selection in shaping landscape genomic structure in red grouse (Lagopus lagopus scotica).

Science.gov (United States)

Wenzel, Marius A; Douglas, Alex; James, Marianne C; Redpath, Steve M; Piertney, Stuart B

2016-01-01

Landscape genomics promises to provide novel insights into how neutral and adaptive processes shape genome-wide variation within and among populations. However, there has been little emphasis on examining whether individual-based phenotype-genotype relationships derived from approaches such as genome-wide association (GWAS) manifest themselves as a population-level signature of selection in a landscape context. The two may prove irreconcilable as individual-level patterns become diluted by high levels of gene flow and complex phenotypic or environmental heterogeneity. We illustrate this issue with a case study that examines the role of the highly prevalent gastrointestinal nematode Trichostrongylus tenuis in shaping genomic signatures of selection in red grouse (Lagopus lagopus scotica). Individual-level GWAS involving 384 SNPs has previously identified five SNPs that explain variation in T. tenuis burden. Here, we examine whether these same SNPs display population-level relationships between T. tenuis burden and genetic structure across a small-scale landscape of 21 sites with heterogeneous parasite pressure. Moreover, we identify adaptive SNPs showing signatures of directional selection using F(ST) outlier analysis and relate population- and individual-level patterns of multilocus neutral and adaptive genetic structure to T. tenuis burden. The five candidate SNPs for parasite-driven selection were neither associated with T. tenuis burden on a population level, nor under directional selection. Similarly, there was no evidence of parasite-driven selection in SNPs identified as candidates for directional selection. We discuss these results in the context of red grouse ecology and highlight the broader consequences for the utility of landscape genomics approaches for identifying signatures of selection. © 2015 John Wiley & Sons Ltd.

Metabolic flexibility: the key to long-term evolutionary success in Bryozoa?

OpenAIRE

Peck, Lloyd S; Barnes, David K A

2004-01-01

Oxygen consumption (MO2) and activity were evaluated in Antarctic Bryozoa. Three species representing two different morphologies, flat sheet, laminar forms, Isoseculiflustra tenuis and Kymella polaris, and the bush form Camptoplites bicornis were used. In Bryozoa, activity is measured as the proportion of colony zooids with their lophophores extended. In I. tenuis and K. polaris, residual analysis showed that the percentage of zooids with extended lophophores was not correlated with colony MO...

The influence of detergents on the bioproduction of organic matter and the enzymatic activity of two fungal species

OpenAIRE

Stojanović Jelica; Veličković D.; Vučetić J.

2002-01-01

The effects of a detergent product (Merix, Merima, Krusevac) o the production of aminoacids and monosaccharides and the proteolytic enzyme activity of the fungi Alternariae tenuis am Trichotecium roseum were examined. After incubation for 8 days the concentrations of all aminoacids except for isoleucine in the case of A tenuis and alanine in the case of T. roseum, were found to be lower it media with 1 % detergent than in the control media without acfcfeo detergent. However, progressively inc...

Nota sobre el género Imperata (Poaceae, Panicoideae, Sacchareae) en Argentina

OpenAIRE

Peichoto, Myriam Carolina

2017-01-01

En este trabajo se confirma la presencia de Imperata tenuis en Argentina. Se presenta una ilustración, material de referencia y un mapa de su distribución geográfica en el sur de Sudamérica. Se incluye una clave para identificar las especies del género Imperata presentes en la Argentina. This work confirms the presence of Imperata tenuis in Argentina, and includes an illustration, reference material, a map showing its geographic distribution in southern South America, and a key to identi...

Hemoparasites of raccoons (Procyon lotor) in Florida.

Science.gov (United States)

Telford, S R; Forrester, D J

1991-07-01

Four hemoparasite species (Babesia lotori, Trypanosoma cruzi, Dirofilaria tenuis and Mansonella llewellyni) were found in raccoons (Procyon lotor) collected from 1972 to 1974 in Duval (n = 14) and Collier (n = 170) counties, Florida (USA). Trypanosoma cruzi was found in thin blood smears from one raccoon at each locality. The prevalence of B. lotori was 79% and 80% in samples taken in December 1973 in Collier and Duval counties, respectively. No patent infections by B. lotori were detected in raccoons collected in Collier County in December 1972, but 42% of the raccoons examined in September 1973 were infected. In Collier County there were no significant differences in the prevalence of B. lotori by host sex or age. In Duval County, overall D. tenuis prevalence was 7%, whereas that of M. llewellyni was 14%; the latter species was not found in Collier County. Adult raccoons had a significantly greater prevalence of D. tenuis (32%) than did subadults and juveniles (7%), and male raccoons showed a significantly greater prevalence (51%) than did females (8%).

Fine-scale differences in diel activity among nocturnal freshwater planarias (Platyhelminthes: Tricladida

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Cicolani Bruno

2011-04-01

Full Text Available Abstract Background Although most freshwater planarias are well known photonegative organisms, their diel rhythms have never been quantified. Differences in daily activity rhythms may be particularly important for temperate-climate, freshwater planarias, which tend to overlap considerably in spatial distribution and trophic requirements. Methods Activity of stress-free, individually tested young adults of three common planarian species was recorded at 3-h intervals in a 10-d experiment under natural sunlight and photoperiod during autumnal equinox (D:L ~12:12. Individual activity status was averaged over the 10-d experiment, each tested individual thus serving as a true replicate. Twelve individuals per species were tested. Food was provided every 36 h, resulting in alternating day- and nighttime feeding events. Activity during the first post-feeding h was recorded and analyzed separately. Statistical procedures included ANOVAs, correlations, and second-order analyses of angles. Results Dugesia (= Girardia tigrina Girard 1850 exhibited clear nocturnal behavior, Dugesia (= Schmidtea polychroa Schmidt 1861 was predominantly but not exclusively nocturnal, and Polycelis tenuis Ijima 1884 was relatively more active from midnight through noon. Species-specific activity peaks were statistically similar, with peaks at dawn for P. tenuis and just before midnight for the two dugesiids; however, D. tigrina was comparatively more active in the early night hours, while D. polychroa was more active than D. tigrina during daytime. D. tigrina also responded less readily to daytime food addition. P. tenuis remained poorly active and unresponsive throughout the experiment. Individual variability in diel behavior was highest for D. polychroa and lowest for D. tigrina. P. tenuis's general low degree of activity and late activity peak in the experiment may be related to a strong reliance on external stimuli. Conclusions The tested species are mainly nocturnal

Internal parasites of free-ranging guanacos from Patagonia.

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Beldomenico, P M; Uhart, M; Bono, M F; Marull, C; Baldi, R; Peralta, J L

2003-12-01

In the winter of 2000, a greater than 80% reduction in the guanaco population located in Cabo Dos Bahi;as Wildlife Reserve, Chubut, Argentina, was evident due to massive mortality attributed to starvation. Twelve guanacos were necropsied and samples were analyzed at the Parasitology Laboratory of Facultad de Ciencias Veterinarias, Universidad Nacional del Litoral. Fecal analysis revealed developmental stages of Nematodirus sp., Marshallagia sp., Trichuris sp. and Eimeria spp. Histopathological analysis showed the presence of Sarcocystis sp. in muscle and fascia cysts. Other parasites recovered included Dictyocaulus filaria, Trichuris tenuis and Moniezia expansa. Of these, D. filaria and M. expansa possibly reflect interactions with domestic sheep. This is the first time that T. tenuis has been reported in guanacos.

Geography and past climate changes have shaped the evolution of a widespread lizard from the Chilean hotspot.

Science.gov (United States)

Muñoz-Mendoza, Carla; D'Elía, Guillermo; Panzera, Alejandra; Méndez T, Marco A; Villalobos-Leiva, Amado; Sites, Jack W; Victoriano, Pedro F

2017-11-01

The complex orogenic history and structure of Southern South America, coupled with Pleistocene glacial cycles, have generated paleoclimatic and environmental changes that influenced the spatial distribution and genetic composition of natural populations. Despite the increased number of phylogeographic studies in this region and given the frequent idiosyncratic phylogeographic patterns, there is still the need to focus research especially on species that are currently distributed within a wide range of bioclimatic regimes, and that historically have been subject to contrasting scenarios. Liolaemus tenuis is a widely distributed lizard species inhabiting latitudinally in almost 1000km through central and southern Chile. Here we describe the geographical patterns of genetic variation and lineage diversification within L. tenuis, and their association with geography and Pleistocene glaciations, using sequences from one mitochondrial and two nuclear genes, and five microsatellite loci, and covering most of the species distributional range. Our results revealed a high diversity both within and among populations, as well as two phylogeographic breaks, which are consistent with two of the larger rivers of central Chile, the Maipo and Biobío Rivers. Liolaemus tenuis is characterized by several allopatric lineages, especially in its north and central range, which suggest a history of multiple vicariance processes. Conversely, populations found in the southern range, south of the Biobío River, show signatures of recent decreases in effective population sizes, coupled with recent range expansions and secondary contact. Niche "envelope" data are consistent with patterns of genetic variation; both suggest a history of discontinuous areas of relatively stable populations throughout all of the distribution of L. tenuis. These data are also consistent with higher probabilities of habitat suitability north of the Maipo River (ca. 33°S), in both coastal areas and the "Intermediate

Communities and coexistence of benthos in northern limb of Cochin Backwaters

Digital Repository Service at National Institute of Oceanography (India)

Devi, K.S.; Jayalakshmy, K.V.; Venugopal, P.

be considered as a pollution resistant species. Lycastis indica, Paraheteromastus tenuis, Telehspia annandalei, chironimid larvae and Pendora flexousa present at st 8, even though in very low numbers, can be treated as pollution tolerant species. The number...

Effects of Sublethal Concentrations of Insecticides on the Functional Response of Two Mirid Generalist Predators.

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Angeliki F Martinou

Full Text Available The use of agrochemicals particularly pesticides, can hamper the effectiveness of natural enemies, causing disruption in the ecosystem service of biological control. In the current study, the effects of the insecticides thiacloprid and chlorantraniliprole on the functional response curves were assessed for two mirid predator nymphs, Macrolophus pygmaeus Rambur and Nesidiocoris tenuis Reuter. In the absence of insecticides, both predators exhibited a type II functional response when feeding on eggs of the moth Ephestia kuehniella. N. tenuis seems to be a more efficient predator than M. pygmaeus, as model estimated handling time was significantly lower for the former than for the latter. Residual exposure of M. pygmaeus to sublethal concentrations of either insecticide was associated with a change in the asymptote but not the type of the functional response curve. Thiacloprid seems to be the least compatible with M. pygmaeus, as it led to both a significant reduction of the attack rate and an increase in handling time. In contrast, chlorantraniliprole exposure significantly increased the handling time, but not the attack rate of the predator. Residual exposure of N. tenuis to sublethal concentrations of either insecticide did not have a significant effect on the type nor the parameters of the functional response model. The results show that pesticide residues that do not have lethal effects on beneficial arthropods can reduce prey consumption depending on predator species and on likely risks associated with toxicity.

Geographic and habitat partitioning of genetically distinct zooxanthellae (Symbiodinium) in Acropora corals on the Great Barrier Reef.

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Ulstrup, K E; Van Oppen, M J H

2003-12-01

Intra- and intercolony diversity and distribution of zooxanthellae in acroporid corals is largely uncharted. In this study, two molecular methods were applied to determine the distribution of zooxanthellae in the branching corals Acropora tenuis and A. valida at several reef locations in the central section of the Great Barrier Reef. Sun-exposed and shaded parts of all colonies were examined. Single-stranded conformational polymorphism analysis showed that individual colonies of A. tenuis at two locations harbour two strains of Symbiodinium belonging to clade C (C1 and C2), whereas conspecific colonies at two other reefs harboured a single zooxanthella strain. A. valida was found to simultaneously harbour strains belonging to two distinct phylogenetic clades (C and D) at all locations sampled. A novel method with improved sensitivity (quantitative polymerase chain reaction using Taqman fluorogenic probes) was used to map the relative abundance distribution of the two zooxanthella clades. At two of the five sampling locations both coral species were collected. At these two locations, composition of the zooxanthella communities showed the same pattern in both coral species, i.e. correlation with ambient light in Pioneer Bay and an absence thereof in Nelly Bay. The results show that the distribution of genetically distinct zooxanthellae is correlated with light regime and possibly temperature in some (but not all) colonies of A. tenuis and A. valida and at some reef locations, which we interpret as acclimation to local environmental conditions.

Effects of Sublethal Concentrations of Insecticides on the Functional Response of Two Mirid Generalist Predators.

Science.gov (United States)

Martinou, Angeliki F; Stavrinides, Menelaos C

2015-01-01

The use of agrochemicals particularly pesticides, can hamper the effectiveness of natural enemies, causing disruption in the ecosystem service of biological control. In the current study, the effects of the insecticides thiacloprid and chlorantraniliprole on the functional response curves were assessed for two mirid predator nymphs, Macrolophus pygmaeus Rambur and Nesidiocoris tenuis Reuter. In the absence of insecticides, both predators exhibited a type II functional response when feeding on eggs of the moth Ephestia kuehniella. N. tenuis seems to be a more efficient predator than M. pygmaeus, as model estimated handling time was significantly lower for the former than for the latter. Residual exposure of M. pygmaeus to sublethal concentrations of either insecticide was associated with a change in the asymptote but not the type of the functional response curve. Thiacloprid seems to be the least compatible with M. pygmaeus, as it led to both a significant reduction of the attack rate and an increase in handling time. In contrast, chlorantraniliprole exposure significantly increased the handling time, but not the attack rate of the predator. Residual exposure of N. tenuis to sublethal concentrations of either insecticide did not have a significant effect on the type nor the parameters of the functional response model. The results show that pesticide residues that do not have lethal effects on beneficial arthropods can reduce prey consumption depending on predator species and on likely risks associated with toxicity.

Fungal associations of roots of dominant and sub-dominant plants in high-alpine vegetation systems with special reference to mycorrhiza.

Science.gov (United States)

Haselwandter, K; Read, D J

1980-04-01

Types of root infection were analysed in healthy dominant and sub-dominant plants of zonal and azonal vegetation above the timberline in the Central and Northern Calcareous Alps of Austria. In the open nival zone vegetation, infection by fungi of the Rhizoctonia type was predominant, vesicular-arbuscular mycorrhizal infection, which was mostly of the fine endophyte (Glomus tenuis) type, being light and mainly restricted to grasses in closed vegetation patches. More extensive Glomus tenuis infection was found in the alpine grass heath, but in Carex, Rhizoctonia was again the most important fungus. The ericaceous plants of the dwarf shrub heath have typical ericoid infection, but quantitative analysis reveals a decrease of infection intensity with increase of altitude. The possible function of the various types of root infection are discussed, and the status of Rhizoctonia as a possible mycorrhizal fungus is considered.

In-vitro antibacterial activity of essential oils extracted from locally available medicinal plants

International Nuclear Information System (INIS)

Ara, G.; Shawar, D.; Akbar, A.; Kanwal, F.; Imran, M.

2011-01-01

Extraction of essential oils from locally available species of four plants, Nigella sativa, Syzygium aromaticum, Cinnamomum tenuis and Curcuma aromatica was carried out using steam distillation followed by ether extraction. Dried and purified extracted oils were screened for their antibacterial activity against three bacterial strains namely, Bacillus lichaniformis (Gram +ve), Micrococcus leutus (Gram +ve) and Salmonella Typhimurium (Gram -ve) using Mc. Cartney's method. Minimum Inhibition Concentration (MIC) values of these oils were also determined. It was observed that the oils extracted from Nigella sativa and Cinnamomum tenuis were found to be more potent as compared to other two species. With the exception of Nigella sativa, all the other oils showed bacterial inhibition at 50 mmol concentration. These results support that these plant oils can be used to cure bacterial infections and may also have role as pharmaceuticals and preservatives. (author)

Whole-cell bioreduction of aromatic α-keto esters using Candida tenuis xylose reductase and Candida boidinii formate dehydrogenase co-expressed in Escherichia coli

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Egger Sigrid

2008-12-01

Full Text Available Abstract Background Whole cell-catalyzed biotransformation is a clear process option for the production of chiral alcohols via enantioselective reduction of precursor ketones. A wide variety of synthetically useful reductases are expressed heterologously in Escherichia coli to a high level of activity. Therefore, this microbe has become a prime system for carrying out whole-cell bioreductions at different scales. The limited capacity of central metabolic pathways in E. coli usually requires that reductase coenzyme in the form of NADPH or NADH be regenerated through a suitable oxidation reaction catalyzed by a second NADP+ or NAD+ dependent dehydrogenase that is co-expressed. Candida tenuis xylose reductase (CtXR was previously shown to promote NADH dependent reduction of aromatic α-keto esters with high Prelog-type stereoselectivity. We describe here the development of a new whole-cell biocatalyst that is based on an E. coli strain co-expressing CtXR and formate dehydrogenase from Candida boidinii (CbFDH. The bacterial system was evaluated for the synthesis of ethyl R-4-cyanomandelate under different process conditions and benchmarked against a previously described catalyst derived from Saccharomyces cerevisiae expressing CtXR. Results Gene co-expression from a pETDuet-1 vector yielded about 260 and 90 units of intracellular CtXR and CbFDH activity per gram of dry E. coli cell mass (gCDW. The maximum conversion rate (rS for ethyl 4-cyanobenzoylformate by intact or polymyxin B sulphate-permeabilized cells was similar (2 mmol/gCDWh, suggesting that the activity of CbFDH was partly rate-limiting overall. Uncatalyzed ester hydrolysis in substrate as well as inactivation of CtXR and CbFDH in the presence of the α-keto ester constituted major restrictions to the yield of alcohol product. Using optimized reaction conditions (100 mM substrate; 40 gCDW/L, we obtained ethyl R-4-cyanomandelate with an enantiomeric excess (e.e. of 97.2% in a yield of 82

Freshwater fishes of Tsitsikamma National Park

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I.A. Russell

2002-12-01

Full Text Available This study aimed to determine the distribution and relative abundance of freshwater fishes in the Tsitsikamma National Park. Fish assemblages in six river systems were sampled in 2001, with a total of 323 fish from eight species recorded. Indigenous fish collected included four freshwater species (Pseudobarbus afer, Pseudobarbus tenuis, Sandelia capensis, Anguilla mossambica, three estuarine species (Monodactylus falciformis, Caffrogobius gilchristi, Myxus capensis, and one alien (Micropterus salmoides. One additional indigenous species (Galaxias zebratus and two aliens (Salmo trutta, Oncorhynchus mykiss could potentially occur within the park. The topography and locality of the park presents a unique opportunity to meaningfully conserve the endangered P. tenuis as well as other fish characteristic of the eastern reaches of the Cape Floristic Region. Management action is required to minimise opportunities for further establishment and spread of alien fish species and to conserve indigenous fish assemblages within the park.

Climate driven range divergence among host species affects range-wide patterns of parasitism

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Richard E. Feldman

2017-01-01

Full Text Available Species interactions like parasitism influence the outcome of climate-driven shifts in species ranges. For some host species, parasitism can only occur in that part of its range that overlaps with a second host species. Thus, predicting future parasitism may depend on how the ranges of the two hosts change in relation to each other. In this study, we tested whether the climate driven species range shift of Odocoileus virginianus (white-tailed deer accounts for predicted changes in parasitism of two other species from the family Cervidae, Alces alces (moose and Rangifer tarandus (caribou, in North America. We used MaxEnt models to predict the recent (2000 and future (2050 ranges (probabilities of occurrence of the cervids and a parasite Parelaphostrongylus tenuis (brainworm taking into account range shifts of the parasite’s intermediate gastropod hosts. Our models predicted that range overlap between A. alces/R. tarandus and P. tenuis will decrease between 2000 and 2050, an outcome that reflects decreased overlap between A. alces/R. tarandus and O. virginianus and not the parasites, themselves. Geographically, our models predicted increasing potential occurrence of P. tenuis where A. alces/R. tarandus are likely to decline, but minimal spatial overlap where A. alces/R. tarandus are likely to increase. Thus, parasitism may exacerbate climate-mediated southern contraction of A. alces and R. tarandus ranges but will have limited influence on northward range expansion. Our results suggest that the spatial dynamics of one host species may be the driving force behind future rates of parasitism for another host species.

Biannual Spawning and Temporal Reproductive Isolation in Acropora Corals.

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James P Gilmour

Full Text Available Coral spawning on the oceanic reef systems of north-western Australia was recently discovered during autumn and spring, but the degree to which species and particularly colonies participated in one or both of these spawnings was unknown. At the largest of the oceanic reef systems, the participation by colonies in the two discrete spawning events was investigated over three years in 13 species of Acropora corals (n = 1,855 colonies. Seven species spawned during both seasons; five only in autumn and one only in spring. The majority of tagged colonies (n = 218 spawned once a year in the same season, but five colonies from three species spawned during spring and autumn during a single year. Reproductive seasonality was not influenced by spatial variation in habitat conditions, or by Symbiodinium partners in the biannual spawner Acropora tenuis. Colonies of A. tenuis spawning during different seasons separated into two distinct yet cryptic groups, in a bayesian clustering analysis based on multiple microsatellite markers. These groups were associated with a major genetic divergence (G"ST = 0.469, despite evidence of mixed ancestry in a small proportion of individuals. Our results confirm that temporal reproductive isolation is a common feature of Acropora populations at Scott Reef and indicate that spawning season is a genetically determined trait in at least A. tenuis. This reproductive isolation may be punctuated occasionally by interbreeding between genetic groups following favourable environmental conditions, when autumn spawners undergo a second annual gametogenic cycle and spawn during spring.

Production of Ethylene and Carbon Monoxide by Microorganisms

Science.gov (United States)

T. H. Filer; L. R. Brown; S. Brown-Sarobot; S. Martin

1984-01-01

Various quantities of ethylene and carbon monoxide were produced on PDA by Fusicladium effusum, Pestilotia nucicola, Alternaria tenuis, and Fusarium oxysporum subcultured from diseased pecan shucks. Repeated subculturing of these fungi on potato dextrose broth supplemented with iron powder produced ethylene. The production of...

Description of a new species of the spider genus Syntrechalea (Araneae: Lycosoidea: Trechaleidae from Colombia Descrição de uma nova espécie de Syntrechalea (Araneae: Lycosoidea: Trechaleidae da Colômbia

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Estevam L. C. da Silva

2008-09-01

Full Text Available A new species of the spider genus Syntrechalea F.O.P.-Cambridge, 1902 is described and illustrated based on material collected in Loreto Mocagua, Colombia. Representatives of this spider genus exhibit an arboreal foraging behavior and are distinguished from the other genera of Trechaleidae by the flattened carapace, long legs and flexible metatarsi and tarsi. New records on the distribution of Syntrechalea tenuis F.O.P.Cambridge, 1902 in Colombia are presented.Uma espécie nova do gênero Syntrechalea F.O.P.-Cambridge, 1902 é descrita e ilustrada, a partir de material coletado em Loreto Mocagua, Colômbia. Os representantes deste gênero apresentam o hábito arbóreo de forragear e são distinguidos dos demais gêneros de Trechaleidae pela carapaça achatada,pernas longas e metatarsos e tarsos flexíveis. Novos registros de distribuição de Syntrechalea tenuis F.O.P.-Cambridge, 1902 na Colômbia são apresentados.

Pathological and rhizospherical studies on root-rot disease of ...

African Journals Online (AJOL)

Isolations from diseased squash roots revealed the presence of Alternaria tenuis, Aspergillus niger, Fusarium oxysporum, F. solani and Rhizoctonia solani. The last two fungi were more frequent than any of the other fungi. Pathogenicity tests proved that squash plants were highly vulnerable to attack by Fusarium solani and ...

Phylogenetic analysis of subgenus vigna species using nuclear ribosomal RNA ITS: evidence of hybridization among Vigna unguiculata subspecies.

Science.gov (United States)

Vijaykumar, Archana; Saini, Ajay; Jawali, Narendra

2010-01-01

Molecular phylogeny among species belonging to subgenus Vigna (genus Vigna) was inferred based on internal transcribed spacer (ITS) sequences of 18S-5.8S-26S ribosomal RNA gene unit. Analysis showed a total of 356 polymorphic sites of which approximately 80% were parsimony informative. Phylogenetic reconstruction by neighbor joining and maximum parsimony methods placed the 57 Vigna accessions (belonging to 15 species) into 5 major clades. Five species viz. Vigna heterophylla, Vigna pubigera, Vigna parkeri, Vigna laurentii, and Vigna gracilis whose position in the subgenus was previously not known were placed in the section Vigna. A single accession (Vigna unguiculata ssp. tenuis, NI 1637) harbored 2 intragenomic ITS variants, indicative of 2 different types of ribosomal DNA (rDNA) repeat units. ITS variant type-I was close to ITS from V. unguiculata ssp. pubescens, whereas type-II was close to V. unguiculata ssp. tenuis. Transcript analysis clearly demonstrates that in accession NI 1637, rDNA repeat units with only type-II ITS variants are transcriptionally active. Evidence from sequence analysis (of 5.8S, ITS1, and ITS2) and secondary structure analysis (of ITS1 and ITS2) indicates that the type-I ITS variant probably does not belong to the pseudogenic rDNA repeat units. The results from phylogenetic and transcript analysis suggest that the rDNA units with the type-I ITS may have introgressed as a result of hybridization (between ssp. tenuis and ssp. pubescens); however, it has been epigenetically silenced. The results also demonstrate differential evolution of ITS sequence among wild and cultivated forms of V. unguiculata.

Chronic environmental exposure to Alternaria tenuis may manifest ...

African Journals Online (AJOL)

Their major complaints were: weakness and numbness in legs, dizziness, loss of memory, light-headedness and vertigo, fatigue, getting lost in familiar territory, and confused thoughts. The subjects were evaluated by testing immunologic, basic EEG, and comprehensive neuropsychological tests. Abnormal antibodies to ...

Nursery use of shallow habitats by epibenthic fishes in Maine nearshore waters

Science.gov (United States)

Lazzari, M. A.; Sherman, S.; Kanwit, J. K.

2003-01-01

Species richness and abundance of epibenthic fishes were quantified with daytime beam trawl tows in shallow water habitats during April-November 2000 of three mid-coast Maine estuaries: Casco Bay, Muscongus Bay and the Weskeag River. Five shallow (Gasterosteus aculeatus, Apeltes quadracus, Pungitius pungitius, Myoxocephalus aenaeus, and Cylcopterus lumpus. The fish community of mid-coast estuaries was dominated by young-of-the-year (YOY) and juvenile fishes and all of the habitat types function as nursery areas. Twelve species (38%) of commercial and recreational importance were collected in the three estuaries, but the percentage was higher in Casco Bay (44%) and the Weskeag River (46%). These species included Anguilla rostrata, Clupea harengus, Gadus morhua, Microgadus tomcod, Pollachius virens, Urophycis chuss, Urophycis regia, Urophycis tenuis, Osmerus mordax, Macrozoarces americanus, Tautogolabrus adspersus, and Pleuronectes americanus. Four species, G. morhua, M. tomcod, P. virens, and U. tenuis were more common in spring than summer or autumn. P. americanus was most abundant in summer followed by spring and autumn. This study documents the importance of shallow estuarine areas in Maine as nurseries for these species.

Nota sobre EL GÉNERO Imperata (Poaceae, Panicoideae, Sacchareae en Argentina

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Myriam C. Peichoto

2013-01-01

Full Text Available En este trabajo se confirma la presencia de Imperata tenuis en Argentina. Se presenta una ilustración, material de referencia y un mapa de su distribución geográfica en el sur de Sudamérica. Se incluye una clave para identificar las especies del género Imperata presentes en la Argentina.

Studies on certain aspects of seed-borne fungi. VI. Fungi associated with different cultivars of wheat (Triticum aestivum L.)

OpenAIRE

K. K. Pandey

2014-01-01

Fungi associated with eight cultivars of wheat have been investigated. Twenty seven species were isolated from external and internal surface of all the wheat (Triticum aestivum L.) cultivars respectively. Out of five dominant and subdominant fungi anly Aspergillus terreus and Alternaria tenuis were able to colonize internally. The culture filtrates of test fungi reduced the germination of all wheat varieties up to different degrees.

Benthic and Sedimentologic Studies on the Charleston Harbor Ocean Disposal Area, Charleston Harbor Deepening Project.

Science.gov (United States)

1979-08-01

Nolella stipate 1 Phylum S ipuncula Sipunculid (undet.) 14 Phylum Echiura Echiurid (undet.) 1 Phylum-. Annelida Hvdroides dianthus 27 Sabellaria...undet.) LEr-idomotus subievi.s Sab)ellaria \\’ulgaris HIvdroides dianthus 9 lu- Mloliusca * Polinices duplicatus0 Modiclus mocilolus squarnosus...tenuis Microporella ciliata Schizoporella cornuta Phvlum Annelida H-vdroides dianthus Sabelliaria x’ulgaris 41Ph’iu MToi 7lusca Creoidula olana Phylum

Coccolithophores from the central Arabian Sea: Sediment trap results

Digital Repository Service at National Institute of Oceanography (India)

Mergulhao, L.P.; Mohan, R.; Murty, V.S.N.; Guptha, M.V.S.; Sinha, D.K.

, Anoplosolenia braciliensisi, Calciosolenia murrayi and Oolithotus antillarum. Minor species such as Discosphaera tubifera, Syracosphaera pulchra, Umbellosphaera tenuis, Neosphaera coccolithomor- pha, Algirosphaera oryza, Michaelsarsia adriati- cus, Gladiolithus... profunda, Oolithotus antillarum) are presented (figure 2a?b). In addition to the majority of isolated coccol- iths, a few coccospheres comprising of G. oceanica, E. huxleyi, G. flabellatus, A. oryza, F. profunda, C. leptoporus were also observed...

High-latitude connectivity of the scleractinian coral Acropora tenuis ...

African Journals Online (AJOL)

western Indian Ocean, identified using nuclear intron and mitochondrial ... African Journal of Marine Science ... Results resolved the presence of four putative Acropora clades, genetically disparate according to 3/550 nuclear intron data.

Phylogenomic analysis of the Chilean clade of Liolaemus lizards (Squamata: Liolaemidae based on sequence capture data

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Alejandra Panzera

2017-10-01

Full Text Available The genus Liolaemus is one of the most ecologically diverse and species-rich genera of lizards worldwide. It currently includes more than 250 recognized species, which have been subject to many ecological and evolutionary studies. Nevertheless, Liolaemus lizards have a complex taxonomic history, mainly due to the incongruence between morphological and genetic data, incomplete taxon sampling, incomplete lineage sorting and hybridization. In addition, as many species have restricted and remote distributions, this has hampered their examination and inclusion in molecular systematic studies. The aims of this study are to infer a robust phylogeny for a subsample of lizards representing the Chilean clade (subgenus Liolaemus sensu stricto, and to test the monophyly of several of the major species groups. We use a phylogenomic approach, targeting 541 ultra-conserved elements (UCEs and 44 protein-coding genes for 16 taxa. We conduct a comparison of phylogenetic analyses using maximum-likelihood and several species tree inference methods. The UCEs provide stronger support for phylogenetic relationships compared to the protein-coding genes; however, the UCEs outnumber the protein-coding genes by 10-fold. On average, the protein-coding genes contain over twice the number of informative sites. Based on our phylogenomic analyses, all the groups sampled are polyphyletic. Liolaemus tenuis tenuis is difficult to place in the phylogeny, because only a few loci (nine were recovered for this species. Topologies or support values did not change dramatically upon exclusion of L. t. tenuis from analyses, suggesting that missing data did not had a significant impact on phylogenetic inference in this data set. The phylogenomic analyses provide strong support for sister group relationships between L. fuscus, L. monticola, L. nigroviridis and L. nitidus, and L. platei and L. velosoi. Despite our limited taxon sampling, we have provided a reliable starting hypothesis for

National Register Testing of 42 Prehistoric Archeological Sites on Fort Hood, Texas: The 1996 Season

Science.gov (United States)

1999-12-01

the mussel shells belong to the family Unionidae, but no attempt to identify genus or species was made. At least nine different genera of mussels...ornaments or tools. Four of the modified shells are identifiable to genus : two are cf. Lampsilis sp. (one from 41CV578 and one from 41CV1250), one is... Diospyros texana Eragrostis intermedia Eragrostis trichodes Erigeron tenuis Erioneuron pilosum Erodium texanum Euphorbia roemeriana Evax

Phototoxic effects of PAH and UVA exposure on molecular responses and developmental success in coral larvae

KAUST Repository

Overmans, Sebastian; Nordborg, Mikaela; Rua, Ruben Diaz; Brinkman, Diane L.; Negri, Andrew P.; Agusti, Susana

2018-01-01

Exposure to polycyclic aromatic carbons (PAHs) poses a growing risk to coral reefs due to increasing shipping and petroleum extraction in tropical waters. Damaging effects of specific PAHs can be further enhanced by the presence of ultraviolet radiation, known as phototoxicity. We tested phototoxic effects of the PAHs anthracene and phenanthrene on larvae of the scleractinian coral Acropora tenuis in the presence and absence of UVA (320–400 nm). Activity of superoxide dismutase (SOD) enzyme was reduced by anthracene while phenanthrene and UVA exposure did not have any effect. Gene expression of MnSod remained constant across all treatments. The genes Catalase, Hsp70 and Hsp90 showed increased expression levels in larvae exposed to anthracene, but not phenanthrene. Gene expression of p53 was upregulated in the presence of UVA, but downregulated when exposed to PAHs. The influence on stress-related biochemical pathways and gene expresson in A. tenuis larvae was considerably greater for anthracene than phenanthrene, and UVA-induced phototoxicity was only evident for anthracene. The combined effects of UVA and PAH exposure on larval survival and metamorphosis paralleled the sub-lethal stress responses, clearly highlighting the interaction of UVA on anthracene toxicity and ultimately the coral’s development.

Phototoxic effects of PAH and UVA exposure on molecular responses and developmental success in coral larvae

KAUST Repository

Overmans, Sebastian

2018-03-09

Exposure to polycyclic aromatic carbons (PAHs) poses a growing risk to coral reefs due to increasing shipping and petroleum extraction in tropical waters. Damaging effects of specific PAHs can be further enhanced by the presence of ultraviolet radiation, known as phototoxicity. We tested phototoxic effects of the PAHs anthracene and phenanthrene on larvae of the scleractinian coral Acropora tenuis in the presence and absence of UVA (320–400 nm). Activity of superoxide dismutase (SOD) enzyme was reduced by anthracene while phenanthrene and UVA exposure did not have any effect. Gene expression of MnSod remained constant across all treatments. The genes Catalase, Hsp70 and Hsp90 showed increased expression levels in larvae exposed to anthracene, but not phenanthrene. Gene expression of p53 was upregulated in the presence of UVA, but downregulated when exposed to PAHs. The influence on stress-related biochemical pathways and gene expresson in A. tenuis larvae was considerably greater for anthracene than phenanthrene, and UVA-induced phototoxicity was only evident for anthracene. The combined effects of UVA and PAH exposure on larval survival and metamorphosis paralleled the sub-lethal stress responses, clearly highlighting the interaction of UVA on anthracene toxicity and ultimately the coral’s development.

Infection Dynamics Vary between Symbiodinium Types and Cell Surface Treatments during Establishment of Endosymbiosis with Coral Larvae

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Bette Lynn Willis

2011-07-01

Full Text Available Symbioses between microbes and higher organisms underpin high diversity in many ecosystems, including coral reefs, however mechanisms underlying the early establishment of symbioses remain unclear. Here we examine the roles of Symbiodinium type and cell surface recognition in the establishment of algal endosymbiosis in the reef-building coral, Acropora tenuis. We found 20–70% higher infection success (proportion of larvae infected and five-fold higher Symbiodinium abundance in larvae exposed to ITS-1 type C1 compared to ITS-1 type D in the first 96 h following exposure. The highest abundance of Symbiodinium within larvae occurred when C1-type cells were treated with enzymes that modified the 40–100 kD glycome, including glycoproteins and long chain starch residues. Our finding of declining densities of Symbiodinium C1 through time in the presence of intact cell surface molecules supports a role for cell surface recognition molecules in controlling post-phagocytosis processes, leading to rejection of some Symbiodinium types in early ontogeny. Reductions in the densities of unmodified C1 symbionts after 96 h, in contrast to increases in D symbionts may suggest the early initiation of a winnowing process contributing to the establishment of Symbiodinium D as the dominant type in one-month old juveniles of A. tenuis.

Seed Biology of Medicinal Plants (IX) : The Relationship of Corydalis Species Derived by Gel Electrophoresis

OpenAIRE

米田, 該典; 加賀, 順二; 那須, 正夫; KAISUKE, YONEDA; JUNJI, KAGA; MASAO, NASU; 大阪大学薬学部; 大阪大学薬学部; 大阪大学薬学部; Faculty of Pharmaceutical Sciences, Osaka University; Faculty of Pharmaceutical Sciences, Osaka University; Faculty of Pharmaceutical Sciences, Osaka University

1987-01-01

The saline soluble protein fraction of seeds of the Corydalis species (Papaveraceae) in Japan was examined by polyacrylamide gel electrophoresis and SDS-polyacrylamide gel electrophoresis. The esterase zymogram suggested that C. pallida, C. pallida var. tenuis, C. heterocarpa var. japonica and C. speciosa, having yellow flowers and no tuber, are closely related to each other. Electrophoresis and SDS-electrophoresis patterns also coincided with the result of the esterase zymogram. They also su...

Synopsis of Dorstenia (Moraceae in Rio Grande do Sul, Southern Brazil

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Bruna De Oliveira Boeni

2015-06-01

Full Text Available A taxonomic synopsis of Dorstenia (Moraceae in Rio Grande do Sul (RS, Southern Brazil, is presented. Three species were recorded: D. brasiliensis, D. carautae, a new record for the state of RS, and D. tenuis. All species are described and illustrated through detailed photos of living specimens. A taxonomic key to separate the species, as well as details on distribution, overall phenology, habitat, conservation status and ecology are presented.

Post Gliphosate treatments establishment of some grasses

OpenAIRE

Ioan ROTAR; Mariana RUSU; Fl. PRICA

1997-01-01

The sward dominated by Festuca rubra/Agrostis tenuis was treated to reduce the Nardus component and others weed by spraying with Gliphosate. Treatments were applied in the autumn of 1993. In the spring of 1994 a mixture of Phleum pratense, Fesuca rubra, Dactylis glomerata, Trifolium repens and Lotus corniculatus was oversown. Establishment of each species and botanical composition of the pasture were measured over the next three years. Nardus and weed was largely replaced by Phleum/Festuca mi...

Further new additions to the lichen mycota of Andhra Pradesh, India

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S. Mohabe

2014-07-01

Full Text Available During the lichen exploration in Rayalaseema region of Andhra Pradesh several interesting lichen taxa were collected of which 10 species are reported here as new records for the state. The species includes Biatorella conspersa (Biatorellaceae, Caloplaca bassiae, C. poliotera (Teloschistaceae, Dimelaena tenuis (Physciaceae, Lecanora chlarotera, L. helva, L. interjecta, L. psuedistera (Lecanoraceae, Pertusaria melastomella (Pertusariaceae and Porina tetracerae (Porinaceae. These taxa / species have been enumerated along with their characteristic features and distributional notes.

Characterization of microsatellite loci for the stingless bee Scaura latitarsis (Hymenoptera, Apidae, Meliponini

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Flávio Francisco

2013-01-01

Full Text Available Seven microsatellite loci were isolated and characterized from a microsatellite enriched genomic library for the stingless bee Scaura latitarsis. Primers were tested in 12 individuals. The number of alleles per locus ranged from 3 to 6 (mean = 4.29 and observed heterozygosity ranged from 0.00 to 0.75 (mean = 0.40. Cross-species tests showed successful amplification for Scaura atlantica, Scaura longula, Scaura tenuis, Schwarzula timida, Schwarziana quadripunctata, Plebeia droryana, and Plebeia remota.

A new species of Chameleon (Sauria: Chamaeleonidae: Kinyongia highlights the biological affinities between the Southern Highlands and Eastern Arc Mountains of Tanzania

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Michele Menegon

2015-12-01

Full Text Available A new species of chameleon is described from the Livingstone and Udzungwa Mountains of Tanzania. The new species is morphologically most similar to Kinyongia vanheygeni. Furthermore, a single, short rostral appendage shows the species similarity to other Eastern Arc endemic Kinyongia species (e.g. K. uthmoelleri, K. oxyrhina, K. magomberae and K. tenuis. Females of all these species lack any rostral ornamentation and are all very similar morphologically. Males of the new species, on which the morphological diagnosis is based, can be distinguished from other Kinyongia by a shorter rostral appendage that bifurcates at the tip. They are easily distinguished from K. vanheygeni, otherwise the most similar species, by differences in head scalation and the length and shape of the rostral appendage. The new species is associated with montane rainforest and is known from only four forest fragments of which two are in the Udzungwa and two in the Livingstone Mountains. Phylogenetically, the new species is sister to K. tenuis and K. magomberae, which together, form a clade that also contains K. oxyrhina. The disjunct distribution of the new species, in the Livingstone and Udzungwa mountains, stretches across the ‘Makambako Gap’ which is a putative biogeographical barrier separating the distinct faunas of the Southern highlands and Eastern Arc Mountains. Evidence from this species however, points to potentially closer biological affinities between the Livingstone and Udzungwa mountains.

Fungitoxicity of metal ions

Energy Technology Data Exchange (ETDEWEB)

Somers, E

1961-01-01

The in vitro fungistatic activity of some twenty-four metal cations has been determine against Alternaria tenuis and Botrytis fabae. The metal salts, mainly nitrates, were tested in aqueous solution without added spore germination stimulant. The logarithm of the metal ion concentration at the ED 50 value has been found to conform to the exponenttial relationship with electronegativity proposed by Danielli and Davies (1951). These results are discussed in relation to the site of action of metal cations on the fungal cell.

Elaeophora in the meninges of a Malayan sambar (Rusa unicolor equina).

Science.gov (United States)

Bernard, Jennifer; Grunenwald, Caroline; Stalis, Ilse H; Varney, Megan; Zuba, Jeff; Gerhold, Richard

2016-11-01

An adult nematode was grossly identified in the meninges of a Malayan sambar (Rusa unicolor equina), with numerous microfilariae associated with encephalitis and vasculitis on histopathology. The nematode was confirmed to be Elaeophora schneideri by sequencing a portion of the 18S rRNA gene. Our report highlights the potential for aberrant migration of E. schneideri in exotic deer species and the use of advanced testing to specifically identify this metazoan parasite, avoiding misidentification of Parelaphostrongylus tenuis. © 2016 The Author(s).

Metabolic flexibility: the key to long-term evolutionary success in Bryozoa?

Science.gov (United States)

Peck, Lloyd S; Barnes, David K A

2004-02-07

Oxygen consumption (MO2) and activity were evaluated in Antarctic Bryozoa. Three species representing two different morphologies, flat sheet, laminar forms, Isoseculiflustra tenuis and Kymella polaris, and the bush form Camptoplites bicornis were used. In Bryozoa, activity is measured as the proportion of colony zooids with their lophophores extended. In I. tenuis and K. polaris, residual analysis showed that the percentage of zooids with extended lophophores was not correlated with colony MO2. Lophophore extension is, therefore, a poor measure of activity, and other costs (e.g. growth, reproduction, storage) probably form the major metabolic costs. MO2 per unit of ash-free dry mass (AFDM) in the laminar forms was low compared with other Antarctic marine invertebrates, but not lower than brachiopods and echinoderms. However, the lowest rate here, 16.8 microg O2 g AFDM(-1) h(-1) for a K. polaris colony, is (to our knowledge) the lowest for any animal so far reported. MO2 per unit of AFDM for C. bicornis, however, is among the highest reported for sessile or slow moving Antarctic marine ectotherms, with values similar to those for bivalve and gastropod molluscs. The highest rate, 527 microg O2 g AFDM(-1) h(-1) for one colony is (to our knowledge) the highest reported for polar animals of this type. Extreme diversity in metabolic strategy may explain the bryozoan long evolutionary record and great success in shallow marine environments worldwide.

Asymmetric competition prevents the outbreak of an opportunistic species after coral reef degradation.

Science.gov (United States)

González-Rivero, Manuel; Bozec, Yves-Marie; Chollett, Iliana; Ferrari, Renata; Schönberg, Christine H L; Mumby, Peter J

2016-05-01

Disturbance releases space and allows the growth of opportunistic species, excluded by the old stands, with a potential to alter community dynamics. In coral reefs, abundances of fast-growing, and disturbance-tolerant sponges are expected to increase and dominate as space becomes available following acute coral mortality events. Yet, an increase in abundance of these opportunistic species has been reported in only a few studies, suggesting certain mechanisms may be acting to regulate sponge populations. To gain insights into mechanisms of population control, we simulated the dynamics of the common reef-excavating sponge Cliona tenuis in the Caribbean using an individual-based model. An orthogonal hypothesis testing approach was used, where four candidate mechanisms-algal competition, stock-recruitment limitation, whole and partial mortality-were incorporated sequentially into the model and the results were tested against independent field observations taken over a decade in Belize, Central America. We found that releasing space after coral mortality can promote C. tenuis outbreaks, but such outbreaks can be curtailed by macroalgal competition. The asymmetrical competitive superiority of macroalgae, given by their capacity to pre-empt space and outcompete with the sponge in a size-dependant fashion, supports their capacity to steal the opportunity from other opportunists. While multiple system stages can be expected in coral reefs following intense perturbation macroalgae may prevent the growth of other space-occupiers, such as bioeroding sponges, under low grazing pressure.

Projected near-future levels of temperature and pCO2 reduce coral fertilization success.

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Rebecca Albright

Full Text Available Increases in atmospheric carbon dioxide (pCO2 are projected to contribute to a 1.1-6.4°C rise in global average surface temperatures and a 0.14-0.35 reduction in the average pH of the global surface ocean by 2100. If realized, these changes are expected to have negative consequences for reef-building corals including increased frequency and severity of coral bleaching and reduced rates of calcification and reef accretion. Much less is known regarding the independent and combined effects of temperature and pCO2 on critical early life history processes such as fertilization. Here we show that increases in temperature (+3°C and pCO2 (+400 µatm projected for this century negatively impact fertilization success of a common Indo-Pacific coral species, Acropora tenuis. While maximum fertilization did not differ among treatments, the sperm concentration required to obtain 50% of maximum fertilization increased 6- to 8- fold with the addition of a single factor (temperature or CO2 and nearly 50- fold when both factors interact. Our results indicate that near-future changes in temperature and pCO2 narrow the range of sperm concentrations that are capable of yielding high fertilization success in A. tenuis. Increased sperm limitation, in conjunction with adult population decline, may have severe consequences for coral reproductive success. Impaired sexual reproduction will further challenge corals by inhibiting population recovery and adaptation potential.

Distribution of coccolithophores as a potential proxy in paleoceanography: The case of the Oman Sea monsoonal pattern

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Mojtahedin Elham

2015-02-01

Full Text Available High abundances of coccoliths have been observed in surface sediment samples from near the coasts of the Oman Sea in February 2011. At the end of the NE monsoon, the locally observed high Gephyrocapsa oceanica production is hypothesized to respond to local injections of nutrient-rich deep water into the surface water due to sea-surface cooling leading to convection. The most abundant coccolithophore species are G. oceanica followed by Emiliania huxleyi, Helicosphaera carteri, Calcidiscus leptoporus. Some species, such as Gephyrocapsa muellerae, Gephyrocapsa ericsonii, Umbilicosphaera sibogae, Umbellosphaera tenuis and Florisphaera profunda, are rare. The G. oceanica suggested a prevalence of upwelling conditions or high supply of nutrients in the Oman Sea (especially West Jask at the end of the NE monsoon. E. huxleyi showed low relative abundances at the end of the NE monsoon. Due to the location of the Oman Sea in low latitudes with high temperatures, we have observed low abundances of G. muellerae in the study area. Additionally, we have identified low abundances of G. ericsonii at the end of the NE monsoon. Helicosphaera carteri showed a clear negative response with decreasing amounts (relative abundances at the end of the NE monsoon. C. leptoporus, U. sibogae and U. tenuis have very low relative abundances in the NE monsoon and declined extremely at the end of the NE monsoon. F. profunda, which is known to inhabit the lower photic zone (<100 m depht was rarely observed in the samples.

Distribution of coccolithophores as a potential proxy in paleoceanography: The case of the Oman Sea monsoonal pattern

Science.gov (United States)

Mojtahedin, Elham; Hadavi, Fatemeh; Lak, Razyeh

2015-02-01

High abundances of coccoliths have been observed in surface sediment samples from near the coasts of the Oman Sea in February 2011. At the end of the NE monsoon, the locally observed high Gephyrocapsa oceanica production is hypothesized to respond to local injections of nutrient-rich deep water into the surface water due to sea-surface cooling leading to convection. The most abundant coccolithophore species are G. oceanica followed by Emiliania huxleyi, Helicosphaera carteri, Calcidiscus leptoporus. Some species, such as Gephyrocapsa muellerae, Gephyrocapsa ericsonii, Umbilicosphaera sibogae, Umbellosphaera tenuis and Florisphaera profunda, are rare. The G. oceanica suggested a prevalence of upwelling conditions or high supply of nutrients in the Oman Sea (especially West Jask) at the end of the NE monsoon. E. huxleyi showed low relative abundances at the end of the NE monsoon. Due to the location of the Oman Sea in low latitudes with high temperatures, we have observed low abundances of G. muellerae in the study area. Additionally, we have identified low abundances of G. ericsonii at the end of the NE monsoon. Helicosphaera carteri showed a clear negative response with decreasing amounts (relative abundances) at the end of the NE monsoon. C. leptoporus, U. sibogae and U. tenuis have very low relative abundances in the NE monsoon and declined extremely at the end of the NE monsoon. F. profunda, which is known to inhabit the lower photic zone (<100 m depht) was rarely observed in the samples.

Distribution and role of the genus Oithona (Copepoda: Cyclopoida in the South China Sea

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Lianggen Wang

2017-07-01

Full Text Available The relationships between the small cyclopoid copepod Oithona and hydrological factors, phytoplankton and ichthyoplankton were evaluated using the data obtained in the central South China Sea (SCS in summer 2014. The genus abundance ranged from 6.00 ind. m−3 to 93.75 ind. m−3 with high abundance band occurring in the branch of SCS Monsoon Jet. The lower temperature and higher salinity in the surface water of the band than other zones indicated that deep water intrusion was a positive factor for aggregation of the genus. The community structure of the genus was dominated by Oithona plumifera and Oithona similis made up 97% of the genus abundance associated with Oithona tenuis. The result of db-RDA analysis showed that the community structure of the genus was affected by temperature, Chl a, larval fishes and fish spawns, and temperature was the most important limiting factor. The result of GAMs analysis showed that abundance of O. tenuis, and copepodites were affected by Chl a, larval fishes and fish spawns; abundance of O. similis was affected by Chl a and fish spawns; and abundance of O. plumifera was affected by Chl a and larval fishes. Therefore, we suggest that the branch of SCS Monsoon Jet and deep water intrusion favor aggregation of plankton in the central SCS in summer. We confirm that the temperature is the limiting factor to the reproduction of the genus Oithona in tropic seas and the genus Oithona is a food-web linker between primary production and larval fishes in the central SCS.

The role of natural antibiotics in storage diseases resistance in irradiated tomato fruits

International Nuclear Information System (INIS)

Sharaway, N.S.M.

1981-01-01

Tomato (lycopersicum esculantum L.) is one of the most important vegetable crops in egypt. Fruit rot, mainly due to fungi, are essential obstacles facing the nowadays prejects plannings of the yield production and exportation. Tomato fruits, variety money maker at green mature exposed to acute gamma irradiation doses at 5, 10, 20, 30 and 100 K rad after inoculated with spore suspension of alternaria tenuis , the main casual organism of fruit rot of tomato and control without inoculation. The source of irradiation was cobalt 60. After irradiation , 50 tomato fruits were packed into exporting carton boxes and then were stored at room temperature

On the occurrence of Stenopus tenui- rostris De Man, 1888 in Natal ...

African Journals Online (AJOL)

Department of Biology, Texas A & M University, College. Station, Texas 77843, USA. S. Koslowski c/o Durban Corporation, Durban. Received 8 JQlluary 1990; accepted 5 March 1990. The stenopodidean shrimp Slenopus lenuiroslris De Man,. 1888 is reported from Natal waters for the first time. This record represents a ...

Two new species and new records of Syntrechalea (Araneae: Lycosoidea: Trechaleidae from Brazil

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Estevam L. C. da Silva

2010-06-01

Full Text Available Currently, nine species of Syntrechalea F.O. Pickard-Cambridge, 1902 are known, six of them occurring in Brazil. In this study, two new species of of this genus are described and illustrated from the states of Amazonas and Tocantins, northern Brazil. Syntrechalea neblina sp.nov. can be distinguished from all known species by the bifurcated guide of the median apophysis. Syntrechalea robusta sp.nov. can be distinguished from all known species by the wider and concave ectal division of the retrolateral tibial apophysis. Additionally, new records of S. adis Carico, 2008, S. brasilia Carico, 2008, S. caporiacco Carico, 2008, S. napoensis Carico, 2008, S. syntrechaloides (Mello-Leitão, 1941 and S. tenuis F.O. Pickard-Cambridge, 1902 are provided.

Influence of copper high-tension lines on plants and soils

Energy Technology Data Exchange (ETDEWEB)

Kraal, H.; Ernst, W.

1976-09-01

The copper contents of plants and soils were determined in relation to the distance from copper high-tension lines. In the vicinity of the cables clayey and fenny soils had demonstrably higher copper contents, due to corrosion of the cables, than regions 20 m and more outside the high-tension lines. On these soils, however, copper accumulation in the plants was low in comparison with those from a sandy soil, although this soil itself showed no copper increase in relation to the cables. The contaminated plants may present a risk of poisoning for sheep within a 20 m distance on both sides of the cables. No changes in plant species composition and in the copper tolerance of Agrostis tenuis were observed.

Invasive alien plants in protected areas within city borders, LODZ (poland)

International Nuclear Information System (INIS)

Anna, B.; Grzegorz, W.J.; Krason, K.

2017-01-01

The aim of the study was to present the occurrence of invasive alien plant species in two forest reserves: "Las Lagiewnicki"and "Polesie Konstantynowskie", located within the city of Lodz (Central Poland). Currently, five vascular plants (Impatiens parviflora, Juncus tenuis, Padus serotina, Quercus rubra, Robinia pseudoacacia) and one moss (Orthodontium lineare) considered as invasive were found in the studied reserves. Invasive plant species accounted for a small percentage of the flora in the studied reserves, and their sites were mainly concentrated in areas transformed by human activity. The most common species were Impatiens parviflora and Padus serotina. Due to the location of the reserves within city borders and the proven negative effect of the found species on ecological systems, their sites should be monitored. (author)

Bolivian Rhinotragini IV: Paraeclipta gen. nov. (Coleoptera, Cerambycidae, new species and new combinations

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Robin O. S. Clarke

2011-01-01

Full Text Available Paraeclipta gen. nov. is described to allocate five new species, and ten transferred from Eclipta Bates, 1873: P. cabrujai sp. nov.; P. clementecruzi sp. nov.; P. melgarae sp. nov.; P. tomhacketti sp. nov.; P. moscosoi sp. nov.; P. bicoloripes (Zajciw, 1965, comb. nov.; P. croceicornis (Gounelle, 1911, comb. nov.; P. flavipes (Melzer, 1922, comb. nov.; P. jejuna (Gounelle, 1911, comb. nov.; P. kawensis (Peñaherrera-Leiva & Tavakilian, 2004, comb. nov.; P. longipennis (Fisher, 1947, comb. nov.; P. rectipennis (Zajciw, 1965, comb. nov.; P. soumourouensis (Tavakilian & Peñaherrera-Leiva, 2003, comb. nov.; P. tenuis (Burmeister, 1865, comb. nov.; and P. unicoloripes (Zajciw, 1965, comb. nov. The Bolivian species are illustrated. A key to their identification and host flower records are provided.

Ectomycorrhizal communities of ponderosa pine and lodgepole pine in the south-central Oregon pumice zone.

Science.gov (United States)

Garcia, Maria O; Smith, Jane E; Luoma, Daniel L; Jones, Melanie D

2016-05-01

Forest ecosystems of the Pacific Northwest of the USA are changing as a result of climate change. Specifically, rise of global temperatures, decline of winter precipitation, earlier loss of snowpack, and increased summer drought are altering the range of Pinus contorta. Simultaneously, flux in environmental conditions within the historic P. contorta range may facilitate the encroachment of P. ponderosa into P. contorta territory. Furthermore, successful pine species migration may be constrained by the distribution or co-migration of ectomycorrhizal fungi (EMF). Knowledge of the linkages among soil fungal diversity, community structure, and environmental factors is critical to understanding the organization and stability of pine ecosystems. The objectives of this study were to establish a foundational knowledge of the EMF communities of P. ponderosa and P. contorta in the Deschutes National Forest, OR, USA, and to examine soil characteristics associated with community composition. We examined EMF root tips of P. ponderosa and P. contorta in soil cores and conducted soil chemistry analysis for P. ponderosa cores. Results indicate that Cenococcum geophilum, Rhizopogon salebrosus, and Inocybe flocculosa were dominant in both P. contorta and P. ponderosa soil cores. Rhizopogon spp. were ubiquitous in P. ponderosa cores. There was no significant difference in the species composition of EMF communities of P. ponderosa and P. contorta. Ordination analysis of P. ponderosa soils suggested that soil pH, plant-available phosphorus (Bray), total phosphorus (P), carbon (C), mineralizable nitrogen (N), ammonium (NH4), and nitrate (NO3) are driving EMF community composition in P. ponderosa stands. We found a significant linear relationship between EMF species richness and mineralizable N. In conclusion, P. ponderosa and P. contorta, within the Deschutes National Forest, share the same dominant EMF species, which implies that P. ponderosa may be able to successfully establish

Removal of phenanthrene from soil by co-cultures of bacteria and fungi pregrown on sugarcane bagasse pith.

Science.gov (United States)

Chávez-Gómez, B; Quintero, R; Esparza-García, F; Mesta-Howard, A M; Zavala Díaz de la Serna, F J; Hernández-Rodríguez, C H; Gillén, T; Poggi-Varaldo, H M; Barrera-Cortés, J; Rodríguez-Vázquez, R

2003-09-01

Sixteen co-cultures composed of four bacteria and four fungi grown on sugarcane bagasse pith were tested for phenanthrene degradation in soil. The four bacteria were identified as Pseudomonas aeruginose, Ralstonia pickettii, Pseudomonas sp. and Pseudomonas cepacea. The four fungi were identified as: Penicillium sp., Trichoderma viride, Alternaria tenuis and Aspergillus terrus that were previously isolated from different hydrocarbon-contaminated soils. Fungi had a statistically significant positive (0.0001

Quantifying fenbendazole and its metabolites in self-medicating wild red grouse Lagopus lagopus scoticus using an HPLC-MS-MS approach.

Science.gov (United States)

Adam, Aileen; Webster, Lucy M I; Mullen, William; Keller, Lukas F; Johnson, Paul C D

2011-05-11

On red grouse estates in the UK the nematode parasite Trichostrongylus tenuis is often controlled by application of grit medicated with the anthelmintic fenbendazole (FBZ). To date, assessment of the efficacy has been inhibited by the inability to quantify uptake of FBZ by the birds. We have developed a simple and sensitive HPLC-MS-MS method for detecting and quantifying FBZ and its metabolites from a 300 mg sample of red grouse liver. This method could be used to improve the efficacy of medicated grit treatment by allowing the identification of conditions and application methods that optimize the uptake of FBZ. With the necessary modifications, our method will also be applicable to other wildlife species where self-medication is used for parasite control. Copyright © 2011 Elsevier B.V. All rights reserved.

Predicting forest insect flight activity: A Bayesian network approach.

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Stephen M Pawson

Full Text Available Daily flight activity patterns of forest insects are influenced by temporal and meteorological conditions. Temperature and time of day are frequently cited as key drivers of activity; however, complex interactions between multiple contributing factors have also been proposed. Here, we report individual Bayesian network models to assess the probability of flight activity of three exotic insects, Hylurgus ligniperda, Hylastes ater, and Arhopalus ferus in a managed plantation forest context. Models were built from 7,144 individual hours of insect sampling, temperature, wind speed, relative humidity, photon flux density, and temporal data. Discretized meteorological and temporal variables were used to build naïve Bayes tree augmented networks. Calibration results suggested that the H. ater and A. ferus Bayesian network models had the best fit for low Type I and overall errors, and H. ligniperda had the best fit for low Type II errors. Maximum hourly temperature and time since sunrise had the largest influence on H. ligniperda flight activity predictions, whereas time of day and year had the greatest influence on H. ater and A. ferus activity. Type II model errors for the prediction of no flight activity is improved by increasing the model's predictive threshold. Improvements in model performance can be made by further sampling, increasing the sensitivity of the flight intercept traps, and replicating sampling in other regions. Predicting insect flight informs an assessment of the potential phytosanitary risks of wood exports. Quantifying this risk allows mitigation treatments to be targeted to prevent the spread of invasive species via international trade pathways.

Marine organisms as source of extracts to disrupt bacterial communication: bioguided isolation and identification of quorum sensing inhibitors from Ircinia felix

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Jairo Quintana

Full Text Available AbstractIn this study, 39 extracts from marine organisms were evaluated as quorum sensing inhibitors, collected in the Colombian Caribbean Sea and the Brazilian Coast including 26 sponges, seven soft corals, five algae and one zooanthid. The results showed that crude extracts from the soft coral Eunicea laciniata, and the sponges Svenzea tubulosa, Ircinia felix and Neopetrosia carbonaria were the most promising source of quorum sensing inhibitors compounds without affecting bacterial growth, unlike the raw extracts of Agelas citrina, Agelas tubulata, Iotrochota arenosa, Topsentia ophiraphidites, Niphates caycedoi, Cliona tenuis, Ptilocaulis walpersi, Petrosia pellasarca, and the algae Laurencia catarinensis and Laurencia obtusa, which displayed potent antibacterial activity against the biosensors employed. The crude extract from the sponge I. felix was fractionated, obtaining furanosesterterpenes which were identified and evaluated as quorum sensing inhibitors, showing a moderate activity without affecting the biosensor's growth.

Chromosome reduction in Eleocharis maculosa (Cyperaceae).

Science.gov (United States)

da Silva, C R M; González-Elizondo, M S; Laforga Vanzela, A L

2008-01-01

Chromosome numbers in Cyperaceae lower than the typical basic number x = 5 have been described for only three species: Rhynchospora tenuis (n = 2), Fimbristylis umbellaris (n = 3) and Eleocharis subarticulata (n = 3). Eleocharis maculosa is recorded here as the fourth species of Cyperaceae that has a chromosome number lower than 2n = 10, with 2n = 8, 7 and 6. The karyotype differentiation in E. maculosa was studied using conventional staining (mitosis and meiosis), FISH with 45S and 5S rDNA and telomere probes. The results allow us to determine which chromosomes of the chromosome race with 2n = 10 fused to form the remaining reduced numbers, as well as to understand how the symploidy and translocation mechanisms were important in karyotype differentiation and the formation of chromosome races in Eleocharis. Copyright 2008 S. Karger AG, Basel.

Occurrence of Hydroclathrus tenuis Tseng and Baoren, (Phaeophyta) from Gulf of Kutch, northwest coast of India

Digital Repository Service at National Institute of Oceanography (India)

Jagtap, T.G.; Untawale, A.G.

of Kutch (India), during February-March 1994. A few ecological and relevant taxonomical observations made on the alga have been described here, which is incidently the first record from the Indian Ocean....

Population Diversity and Dispersal of Two Species of Stoneflies (Order Plecoptera) Within Four Watersheds of Northeastern Ohio.

Science.gov (United States)

Yasick, A. L.; Wolin, J. A.; Krebs, R. A.

2005-05-01

This study investigates two species of stoneflies with potentially opposing dispersal capabilities and genetic structure within four watersheds in the Lake Erie drainage system of Northeast Ohio. This research is two fold; it provides information on genetic variation of two understudied aquatic invertebrate species and the impact of human land-use practices on this variation. Populations of Allocapnia recta, a winter emerging stonefly are predicted to have the least genetic variation within the four watersheds and most differences among sites due to its rudimentary wing structure and winter emergence. Leuctra tenuis is predicted to have greater genetic variability within sites and fewer differences among sites because of its higher migration potential. In both species, models of isolation by distance will be tested. Distinct polymorphisms exist within the 16s rRNA region of A. recta suggesting that this fragment has sufficient variation to address these questions.

Chiasmatic and achiasmatic inverted meiosis of plants with holocentric chromosomes

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Cabral, Gabriela; Marques, André; Schubert, Veit; Pedrosa-Harand, Andrea; Schlögelhofer, Peter

2014-01-01

Meiosis is a specialized cell division in sexually reproducing organisms before gamete formation. Following DNA replication, the canonical sequence in species with monocentric chromosomes is characterized by reductional segregation of homologous chromosomes during the first and equational segregation of sister chromatids during the second meiotic division. Species with holocentric chromosomes employ specific adaptations to ensure regular disjunction during meiosis. Here we present the analysis of two closely related plant species with holocentric chromosomes that display an inversion of the canonical meiotic sequence, with the equational division preceding the reductional. In-depth analysis of the meiotic divisions of Rhynchospora pubera and R. tenuis reveals that during meiosis I sister chromatids are bi-oriented, display amphitelic attachment to the spindle and are subsequently separated. During prophase II, chromatids are connected by thin chromatin threads that appear instrumental for the regular disjunction of homologous non-sister chromatids in meiosis II. PMID:25295686

Scale‐up and intensification of (S)‐1‐(2‐chlorophenyl)ethanol bioproduction: Economic evaluation of whole cell‐catalyzed reduction of o‐Chloroacetophenone

DEFF Research Database (Denmark)

Eixelsberger, Thomas; Woodley, John; Nidetzky, Bernd

2013-01-01

Escherichia coli cells co‐expressing genes coding for Candida tenuis xylose reductase and Candida boidinii formate dehydrogenase were used for the bioreduction of o‐chloroacetophenone with in situ coenzyme recycling. The product, (S)‐1‐(2‐chlorophenyl)ethanol, is a key chiral intermediate...... in the synthesis of polo‐like kinase 1 inhibitors, a new class of chemotherapeutic drugs. Production of the alcohol in multi‐gram scale requires intensification and scale‐up of the biocatalyst production, biotransformation, and downstream processing. Cell cultivation in a 6.9‐L bioreactor led to a more than...... costs by 80% and enabled (S)‐1‐(2‐chlorophenyl)ethanol production within previously defined economic boundaries. A simple and efficient way to synthesize (S)‐1‐(2‐chlorophenyl)ethanol in an isolated amount of 20 g product per reaction batch was demonstrated. Biotechnol. Bioeng. 2013; 110: 2311...

Fungi of genus Alternaria occurring on tomato

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Joanna Marcinkowska

2013-12-01

Full Text Available Tomato early blight in central Poland was caused by Alternaria solani (A. porri f. sp., solani and A. alernata (A. tenuis. A. alternata was isolated more often than A. solani. All isolates of A. solani in controlled conditions killed tomato seedlings, while pathogenic isolates of A. alternata caused only slight seedling blight. In greenhouse tests A. solani proved to be strongly pathogenic for leaves and stems of tomato but A. alternata was weakly pathogenic. The latter species attacked only injured fruits while, A. solanicould penetrate through undamaged peel of fruits. Both of these species caused the same type of symptoms; the differences consisted only in intensification of disease symptoms. During 1974 and 1975 field tomatoes were moderately attacked by early blight. Thebest development of this disease occurred by the turn of August and September. Determinate variety 'New Yorker' was distinguished by more severe infection of stem parts of tomato whereas the fruits of a stock variety 'Apollo' were more strongly attacked.

Comparative genomics of xylose-fermenting fungi for enhanced biofuel production

Energy Technology Data Exchange (ETDEWEB)

Wohlbach, Dana J.; Kuo, Alan; Sato, Trey K.; Potts, Katlyn M.; Salamov, Asaf A.; LaButti, Kurt M.; Sun, Hui; Clum, Alicia; Pangilinan, Jasmyn L.; Lindquist, Erika A.; Lucas, Susan; Lapidus, Alla; Jin, Mingjie; Gunawan, Christa; Balan, Venkatesh; Dale, Bruce E.; Jeffries, Thomas W.; Zinkel, Robert; Barry, Kerrie W.; Grigoriev, Igor V.; Gasch, Audrey P.

2011-02-24

Cellulosic biomass is an abundant and underused substrate for biofuel production. The inability of many microbes to metabolize the pentose sugars abundant within hemicellulose creates specific challenges for microbial biofuel production from cellulosic material. Although engineered strains of Saccharomyces cerevisiae can use the pentose xylose, the fermentative capacity pales in comparison with glucose, limiting the economic feasibility of industrial fermentations. To better understand xylose utilization for subsequent microbial engineering, we sequenced the genomes of two xylose-fermenting, beetle-associated fungi, Spathaspora passalidarum and Candida tenuis. To identify genes involved in xylose metabolism, we applied a comparative genomic approach across 14 Ascomycete genomes, mapping phenotypes and genotypes onto the fungal phylogeny, and measured genomic expression across five Hemiascomycete species with different xylose-consumption phenotypes. This approach implicated many genes and processes involved in xylose assimilation. Several of these genes significantly improved xylose utilization when engineered into S. cerevisiae, demonstrating the power of comparative methods in rapidly identifying genes for biomass conversion while reflecting on fungal ecology.

Bioprocess design guided by in situ substrate supply and product removal: process intensification for synthesis of (S)-1-(2-chlorophenyl)ethanol.

Science.gov (United States)

Schmölzer, Katharina; Mädje, Katharina; Nidetzky, Bernd; Kratzer, Regina

2012-03-01

We report herein on bioprocess development guided by the hydrophobicities of substrate and product. Bioreductions of o-chloroacetophenone are severely limited by instability of the catalyst in the presence of aromatic substrate and (S)-1-(2-chlorophenyl)ethanol. In situ substrate supply and product removal was used to protect the utilized Escherichia coli whole cell catalyst based on Candida tenuis xylose reductase during the reaction. Further engineering at the levels of the catalyst and the reaction media was matched to low substrate concentrations in the aqueous phase. Productivities obtained in aqueous batch reductions were 21-fold improved by addition of 20% (v/v) hexane, NAD(+), expression engineering, cell permeabilization and pH optimization. Reduction of 300 mM substrate was accomplished in 97% yield and use of the co-solvent hexane in subsequent extraction steps led to 88% recovery. Product loss due to high catalyst loading was minimized by using the same extractant in bioreduction and product isolation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Helminth parasites of the raccoon (Procyon lotor) from north-central Arkansas.

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Richardson, D J; Owen, W B; Snyder, D E

1992-02-01

Twenty-three species of helminths (4 trematodes, 2 cestodes, 14 nematodes, and 3 acanthocephalans) were found in the gastrointestinal tract, lungs, pancreas, tongue, urinary bladder, and subcutaneous tissues of 30 live-trapped or hunter-shot raccoons from north-central Arkansas between November 1989 and April 1990. Helminths were not detected in the brain, diaphragm, gallbladder, heart, liver, reproductive system, or trachea. Each raccoon examined was infected with 3 or more of the following helminths: Brachylaima virginiana, Eurytrema procyonis, Fibricola cratera, Pharyngostomoides procyonis, Atriotaenia procyonis, Mesocestoides spp., Arthrocephalus lotoris, Capillaria aerophila, Capillaria plica, Capillaria procyonis, Capillaria putorii, Crenosoma goblei, Cruzia americana, Dirofilaria tenuis, Dracunculus insignis, Enterobius sp., Gnathostoma procyonis, Molineus barbatus, Physaloptera rara, Trichinella spiralis, Centrorhynchus wardae, Macracanthorhynchus ingens, and Oligacanthorhynchus tortuosa. All helminths collected with the exception of D. insignis constitute new geographic distribution records. Occurrences of C. aerophila, C. wardae, and O. tortuosa are new host records. One nymphal pentastome, Porocephalus crotali, was found in the liver of 1 raccoon, constituting a new host record.

Simulated coal spill causes mortality and growth inhibition in tropical marine organisms.

Science.gov (United States)

Berry, Kathryn L E; Hoogenboom, Mia O; Flores, Florita; Negri, Andrew P

2016-05-13

Coal is a principal fossil fuel driving economic and social development, and increases in global coal shipments have paralleled expansion of the industry. To identify the potential harm associated with chronic marine coal contamination, three taxa abundant in tropical marine ecosystems (the coral Acropora tenuis, the reef fish Acanthochromis polyacanthus and the seagrass Halodule uninervis) were exposed to five concentrations (0-275 mg coal l(-1)) of suspended coal dust (coal exposure can cause considerable lethal effects on corals, and reductions in seagrass and fish growth rates. Coral survivorship and seagrass growth rates were inversely related to increasing coal concentrations (≥38 mg coal l(-1)) and effects increased between 14 and 28 d, whereas fish growth rates were similarly depressed at all coal concentrations tested. This investigation provides novel insights into direct coal impacts on key tropical taxa for application in the assessment of risks posed by increasing coal shipments in globally threatened marine ecosystems.

The parasite assemblage in the spiral intestine of the shark Mustelus canis.

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Cislo, P R; Caira, J N

1993-12-01

The parasite assemblage in the 8 chambers of the spiral intestine of 49 specimens of the shark Mustelus canis collected from Long Island Sound and off the coast of Virginia was investigated. Assemblages within host individuals were composed of up to 3 of 4 species of cestodes: the trypanorhynch species Prochristianella tumidula and Lacistorhynchus tenuis and the hooked tetraphyllidean species Calliobothrium verticillatum and Calliobothrium lintoni. Each individual shark hosted 1-3 (mean = 2.17) tapeworm species and 1-166 (mean = 34.3) tapeworm individuals. The assemblage consisted of 2 core species, 1 secondary species, and 1 satellite species. Analysis of variance (ANOVA) revealed significant differences among the areas of the 8 intestinal chambers. ANOVAs of worm density among chambers revealed that each of the 4 species exhibited site specificity within the spiral intestine. Least significant difference analysis revealed that each of the species, except C. verticillatum, was usually found in the anterior 3 chambers. Calliobothrium verticillatum was more commonly found in the middle region of the organ, centered around chamber 4. Horn's information index indicated that L. tenuis and C. lintoni had the greatest amount of overlap within the spiral intestine and the congeners C. lintoni and C. verticillatum had the least amount of overlap. No evidence of interaction among the species in this assemblage was found. In cases where observations could be made, neither cestode total length nor location within the spiral intestine appeared to be affected by the presence of other individuals or species respectively. There was some evidence of underutilized space; the posteriormost chamber was vacant in all 49 sharks examined and 91.8% of sharks had at least 2 vacant chambers. Linear regression revealed no relationship between shark total length and either total number of worms or total number of individuals of each of the 4 species of cestodes. The chi-square test revealed

Increased prevalence of IgG-induced sensitization and hypersensitivity pneumonitis (humidifier lung) in nonsmokers exposed to aerosols of a contaminated air conditioner.

Science.gov (United States)

Baur, X; Richter, G; Pethran, A; Czuppon, A B; Schwaiblmair, M

1992-01-01

Specific IgG antibodies against antigens of a contaminated air conditioner were estimated in serum of 134 workers of a printing company. Altogether 64% of the workers investigated revealed significantly elevated levels (> 3 U/ml) of IgG antibodies specific to these antigens as compared to a nonexposed control group. The occurrence of IgG antibodies for microbial extracts were 25% for Fusarium, 23% for Penicillium notatum, 13% for Alternaria tenuis, 12% for Aureobasidium pullulans, 9% for Sphaeropsidales species, 3% for Micropolyspora faeni, 2% for Aspergillus fumigatus and 2% for Thermoactionomyces vulgaris. Out of the 86 workers with elevated IgG antibodies for air conditioner antigens, 59 were nonsmokers. Considering a cut-off level of 10 U/ml IgG for high values, the proportion of smokers to nonsmokers becomes even more pronounced (6 to 36 respectively, binominal test p air conditioners are the best choice as antigen source for the diagnosis of humidifier lung in exposed workers. Nonsmokers are shown to have a high risk for immunological sensitization.

Simulated coal spill causes mortality and growth inhibition in tropical marine organisms

Science.gov (United States)

Berry, Kathryn L. E.; Hoogenboom, Mia O.; Flores, Florita; Negri, Andrew P.

2016-05-01

Coal is a principal fossil fuel driving economic and social development, and increases in global coal shipments have paralleled expansion of the industry. To identify the potential harm associated with chronic marine coal contamination, three taxa abundant in tropical marine ecosystems (the coral Acropora tenuis, the reef fish Acanthochromis polyacanthus and the seagrass Halodule uninervis) were exposed to five concentrations (0-275 mg coal l-1) of suspended coal dust (<63 μm) over 28 d. Results demonstrate that chronic coal exposure can cause considerable lethal effects on corals, and reductions in seagrass and fish growth rates. Coral survivorship and seagrass growth rates were inversely related to increasing coal concentrations (≥38 mg coal l-1) and effects increased between 14 and 28 d, whereas fish growth rates were similarly depressed at all coal concentrations tested. This investigation provides novel insights into direct coal impacts on key tropical taxa for application in the assessment of risks posed by increasing coal shipments in globally threatened marine ecosystems.

Lipid composition of positively buoyant eggs of reef building corals

Science.gov (United States)

Arai, Iakayuki; Kato, Misako; Heyward, Andrew; Ikeda, Yutaka; Iizuka, Tokio; Maruyama, Tadashi

1993-07-01

Lipid composition of the eggs of three reef building corals, Acropora millepora, A. tenuis and Montipora digitata, were determined. Sixty to 70% of the egg dry weight was lipid, which consisted of wax esters (69.5 81.8%), triacylglycerols (1.1 8.4%) and polar lipids c/mainly phospholipids (11.9 13.2%). Montipora digitata also contained some polar lipids typical of the thylakoid membrane in chloroplasts, probably due to the presence of symbiotic zooxanthellae in the eggs. The wax esters appeared to be the major contributor to positive buoyancy of the eggs, and specific gravity of wax esters in A. millepora was estimated to be 0.92. Among the fatty acids of the wax esters, 34.9 51.3% was hexadecanoic acid (16:0) while the major fatty acids in polar lipids were octadecenoic acid (18:1), hexadecanoic acid (16:0), eicosapentaenoic acid (20:5) and eicosatetraenoic acid (20:4). The wax ester appears to be the main component of the 4.5 6.0 μm diameter lipid droplets which fill most of the central mass of the coral eggs.

Taxonomical, anatomical and chemotaxonomical studies of mosses from Jebel Marra (Darfur State, Sudan), with special reference to their localities

International Nuclear Information System (INIS)

Ahmed, I.M.

2003-02-01

This research represents taxonomical, anatomical, and chemotaxonomical studies of mosses of Jebel Marra, Darfour State, Sudan. This study and for the first time includes the bryoflora checklist of the Sudan which is gathered from many previous studies, in addition to the present study. The fully identified mosses for the study area are 12 species belonging to 8 different families and 10 different genera. Three genera from the family Bottiaceae, 2 from the family Bartramiaceae,2 from Funariaceae, and one genus recorded for each of the families: Ditrichaceae, Bryaceae,Thuidiaceae and Polytrichaceae. Key to the studied genera is constructed and full species description and illustrations of the most taxonomically important characters are included. In this study the genus Ceratodon Brid. Is recorded for the first time in Sudan, and to the specific level, 5 species are encountered for the time: Barbula Ehenbergii, Philonotis tenuis, Philonotis longiseta, Ceratodon Purpureus, and Thuidium furfurosum. For each species determination of the levels of the heavy metal: sodium, potassium, zinc, cobalt, copper, manganese and iron are studied, in addition to nitrogen and chlorophyll content. ( Author)

Improvement of selective removal of heavy metals in cyanobacteria by NaOH treatment.

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Nagase, Hiroyasu; Inthorn, Duangrat; Oda, Aiko; Nishimura, Jun; Kajiwara, Yumiko; Park, Myong-Oku; Hirata, Kazumasa; Miyamoto, Kazuhisa

2005-04-01

In the freshwater cyanobacterium, Tolypothrix tenuis, treatment with 0.1 M NaOH increased its Cd-selective adsorption ability in the presence of Ca(2+) or Mg(2+). The selective adsorption was also achieved by other alkaline treatments. Energy-distributed spectroscopy analysis revealed that Cd(2+) was found mainly on the surface of non-treated cells, whereas it was distributed throughout the cell after NaOH treatment. The alkaline treatment was effective in increasing the selective adsorption ability of the cyanobacterium for other bivalent heavy metals such as Cu(2+), Pb(2+) and Zn(2+). The treatment was also applicable to Anabaena variabilis and Microcystis aeruginosa, which are typical cyanobacteria causing algal blooms. The main binding site of Cd(2+) in NaOH-treated cells is assumed to be the carboxyl groups because the binding ability of the cells was diminished by the esterification of carboxyl groups. These results suggest that alkaline treatment of cyanobacteria is a useful technique for producing biosorbents having highly specific binding abilities for heavy metals.

Çapalı Gölü (Afyon Makrobentik Omurgasızlarının Taban Yapısı ve Su Kalitesine Bağlı Olarak Dağılımı.

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Ö. Osman Ertan

2015-12-01

Full Text Available Temmuz 2000 ve Haziran 2001 tarihleri arasında yapılan bu çalışmada, Çapalı Gölü’nün bazı su kalitesi parametreleri ile makrobentik omurgasızlarının dağılım ve yoğunluğu ikişer ay arayla, bir yıl boyunca izlenmiştir. Kaynak suyu özelliği gösteren I. istasyonda Theodoxus anatolicus (Recluz, 1841, Graecoanatolica tenuis (Radoman, 1943 (Gastropoda ve Trichoptera larvaları yoğun olarak bulunurken; mezotrofik ve ötrofik özellik gösteren II. ve III. istasyonlarda makrobentik organizma çeşitliliği ve yoğunluğunun çok düşük düzeyde olduğu tespit edilmiştir. Ötrofik-hiperötrofik özellikte olan IV. istasyonda ise Chironomus larvaları (Diptera, Tubifex sp. (Oligochaeta ve Asellus aquaticus (Linnaeus, 1758 (Isopoda yoğun olarak belirlenmiştir

The occurrence of alien species in the settlement areas of the Kampinos National Park and its vicinity (Central Poland

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Kirpluk Izabella

2015-09-01

Full Text Available Studies aimed at the identification of the range and method of spread of alien plant species in settlement areas in Kampinos National Park (KNP and its immediate vicinity were carried out in years 2012-2014. Special emphasis was put on surveying the sites of invasive alien species (IAS, and diagnosing potential threats posed to the natural and semi-natural vegetation of the national park by the IAS present in rural areas. We found 53 alien vascular plant species, including 40 invasive taxa which may potentially pose a threat to the ecosystems of KNP. Species encroaching from settlement areas to semi-natural and natural communities included: Bidens frondosa, Echinocystis lobata, Impatiens glandulifera, I. parviflora, Juncus tenuis, Lupinus polyphyllus, Reunoutria japonica and Solidago gigantea. Most of them were species from the highest invasiveness (IV and III classes in Poland. Similarity analysis carried out for all investigated localities with regard to all alien species, and only for invasive ones showed a clear division into separate groups: villages within the boundaries of the national park and villages outside the park.

Comparing the Effects of Symbiotic Algae (Symbiodinium) Clades C1 and D on Early Growth Stages of Acropora tenuis

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Yuyama, Ikuko; Higuchi, Tomihiko

2014-01-01

Reef-building corals switch endosymbiotic algae of the genus Symbiodinium during their early growth stages and during bleaching events. Clade C Symbiodinium algae are dominant in corals, although other clades — including A and D — have also been commonly detected in juvenile Acroporid corals. Previous studies have been reported that only molecular data of Symbiodinium clade were identified within field corals. In this study, we inoculated aposymbiotic juvenile polyps with cultures of clades C1 and D Symbiodinium algae, and investigated the different effect of these two clades of Symbiodinium on juvenile polyps. Our results showed that clade C1 algae did not grow, while clade D algae grew rapidly during the first 2 months after inoculation. Polyps associated with clade C1 algae exhibited bright green fluorescence across the body and tentacles after inoculation. The growth rate of polyp skeletons was lower in polyps associated with clade C1 algae than those associated with clade D algae. On the other hand, antioxidant activity (catalase) of corals was not significantly different between corals with clade C1 and clade D algae. Our results suggested that clade D Symbiodinium algae easily form symbiotic relationships with corals and that these algae could contribute to coral growth in early symbiosis stages. PMID:24914677

Uridine 3H-5 and leucine 3H-5 uptake in Planarian cells Polycelis tenuis (Iijima) cultivated in vitro

International Nuclear Information System (INIS)

Franquinet, Raphael; Le Moigne, Albert; Lender, Theodore

1975-01-01

RNA and protein synthesis in planarian cells cultivated in vitro was studied by histoautoradiography. In the non-differentiated cells, uptake of precursor is intense from the beginning of the culture, and sensitive to addition of trophic factor known for their activating effect on mitosis and regeneration. On the contrary the rate of incorporation in differentiated cells is low and uniform, independently of the differents factors added to the medium [fr

BUDI DAYA KARANG HIAS MENDUKUNG PERDAGANGAN KARANG HIAS YANG BERKESINAMBUNGAN

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Ofri Johan

2007-12-01

Full Text Available Kegiatan budi daya karang hias di Indonesia perlu dilakukan untuk menjamin perdagangannya agar berjalan tanpa merusak keanekaragaman dan kondisi terumbu karang. Budi daya karang hias menggunakan rak berupa meja yang terbuat dari paralon PVC yang dinilai sangat ekonomis dan mudah diaplikasikan masyarakat lokal. Pengamatan pertumbuhan hanya dilakukan pada 1 rak masing-masing jenis karang yang dibudidayakan yaitu Acropora sp., Acropora formosa, Acropora humilis, Acropora millepora, Acropora nobilis, dan Seriatopora hystrix. Kegiatan dilakukan pada dua lokasi yaitu Pulau Simakakang-Mentawai, Sumatera Barat dan Gondol, Bali. Pengamatan dilakukan setiap dua bulan dan penelitian dilaksanakan selama 6 bulan. Hasil pengamatan diperoleh tingkat mortalitas pada lokasi Pulau Simakakang diperoleh 5,56% dari 36 sampel yang diukur dari 6 jenis karang dan 6 ulangan, pertambahan panjang jenis A. formosa 0,64 cm/bulan, lebih cepat dibandingkan dengan jenis A. millepora 0,58 cm/bulan dan jenis lain. Karang A. humilis memiliki laju perambatan pada substrat semen dan batang pengikat yang  lebih cepat dari jenis lain. Pada lokasi Gondol, Bali memiliki laju pertambahan panjang karang A. millepora lebih cepat (0,50 cm/bulan dibandingkan dengan jenis A. tenuis (0,43 cm/bulan dan jenis lain berkisar antara 0,21—0,39 cm/bulan.Tingkat kematian 3 koloni (7,1% dari total 42 koloni yang disampling. The culture of ornamental coral is important to be conducted to guarantee the coral trade can be run well without giving impact to coral reef biodiversities and coral reef condition in Indonesia. This cultured using table using nets as a place which is made from PVC pipe. This method can minimize cost comparing with others materials as well as applicable for coastal community. One table can be placed 12 (3x4 substrate with a distance among others of 25 cm, then fragmented coral were tied to that substrates. This activity was carried out in two locations that were Simakakang

Seasonal forcing in a host-macroparasite system.

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Taylor, Rachel A; White, Andrew; Sherratt, Jonathan A

2015-01-21

Seasonal forcing represents a pervasive source of environmental variability in natural systems. Whilst it is reasonably well understood in interacting populations and host-microparasite systems, it has not been studied in detail for host-macroparasite systems. In this paper we analyse the effect of seasonal forcing in a general host-macroparasite system with explicit inclusion of the parasite larval stage and seasonal forcing applied to the birth rate of the host. We emphasise the importance of the period of the limit cycles in the unforced system on the resulting dynamics in the forced system. In particular, when subject to seasonal forcing host-macroparasite systems are capable of multi-year cycles, multiple solution behaviour, quasi-periodicity and chaos. The host-macroparasite systems show a larger potential for multiple solution behaviour and a wider range of periodic solutions compared to similar interacting population and microparasite systems. By examining the system for parameters that represent red grouse and the macroparasite nematode Trichostrongylus tenuis we highlight how seasonality could be an important factor in explaining the wide range of seemingly uncorrelated cycle periods observed in grouse abundance in England and Scotland. Copyright © 2014 Elsevier Ltd. All rights reserved.

Species-delimitation and phylogenetic analyses of some cosmopolitan species of Hypnea (Rhodophyta) reveal synonyms and misapplied names to H. cervicornis, including a new species from Brazil.

Science.gov (United States)

de Jesus, Priscila Barreto; Nauer, Fabio; Lyra, Goia de Mattos; Cassano, Valéria; Oliveira, Mariana Cabral; Nunes, José Marcos de Castro; Schnadelbach, Alessandra Selbach

2016-10-01

Hypnea has an intricate nomenclatural history due to a wide pantropical distribution and considerable morphological variation. Recent molecular studies have provided further clarification on the systematics of the genus; however, species of uncertain affinities remain due to flawed taxonomic identification. Detailed analyses coupled with literature review indicated a strong relationship among H. aspera, H. cervicornis, H. flexicaulis, and H. tenuis, suggesting a need for further taxonomic studies. Here, we analyzed sequences from two molecular markers (COI-5P and rbcL) and performed several DNA-based delimitation methods (mBGD, ABGD, SPN, PTP and GMYC). These molecular approaches were contrasted with morphological and phylogenetic evidence from type specimens and/or topotype collections of related species under a conservative approach. Our results demonstrate that H. aspera and H. flexicaulis represent heterotypic synonyms of H. cervicornis and indicate the existence of a misidentified Hypnea species, widely distributed on the Brazilian coast, described here as a new species: H. brasiliensis. Finally, inconsistencies observed among our results based on six different species delimitation methods evidence the need for adequate sampling and marker choice for different methods. © 2016 Phycological Society of America.

Biotic control of skeletal growth by scleractinian corals in aragonite-calcite seas.

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Tomihiko Higuchi

Full Text Available Modern scleractinian coral skeletons are commonly composed of aragonite, the orthorhombic form of CaCO3. Under certain conditions, modern corals produce calcite as a secondary precipitate to fill pore space. However, coral construction of primary skeletons from calcite has yet to be demonstrated. We report a calcitic primary skeleton produced by the modern scleractinian coral Acropora tenuis. When uncalcified juveniles were incubated from the larval stage in seawater with low mMg/Ca levels, the juveniles constructed calcitic crystals in parts of the primary skeleton such as the septa; the deposits were observable under Raman microscopy. Using scanning electron microscopy, we observed different crystal morphologies of aragonite and calcite in a single juvenile skeleton. Quantitative analysis using X-ray diffraction showed that the majority of the skeleton was composed of aragonite even though we had exposed the juveniles to manipulated seawater before their initial crystal nucleation and growth processes. Our results indicate that the modern scleractinian coral Acropora mainly produces aragonite skeletons in both aragonite and calcite seas, but also has the ability to use calcite for part of its skeletal growth when incubated in calcite seas.

Coral-bacterial communities before and after a coral mass spawning event on Ningaloo Reef.

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Janja Ceh

Full Text Available Bacteria associated with three coral species, Acropora tenuis, Pocillopora damicornis and Tubastrea faulkneri, were assessed before and after coral mass spawning on Ningaloo Reef in Western Australia. Two colonies of each species were sampled before and after the mass spawning event and two additional samples were collected for P. damicornis after planulation. A variable 470 bp region of the 16 S rRNA gene was selected for pyrosequencing to provide an understanding of potential variations in coral-associated bacterial diversity and community structure. Bacterial diversity increased for all coral species after spawning as assessed by Chao1 diversity indicators. Minimal changes in community structure were observed at the class level and data at the taxonomical level of genus incorporated into a PCA analysis indicated that despite bacterial diversity increasing after spawning, coral-associated community structure did not shift greatly with samples grouped according to species. However, interesting changes could be detected from the dataset; for example, α-Proteobacteria increased in relative abundance after coral spawning and particularly the Roseobacter clade was found to be prominent in all coral species, indicating that this group may be important in coral reproduction.

The skin prick test – European standards

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Heinzerling Lucie

2013-02-01

Full Text Available Abstract Skin prick testing is an essential test procedure to confirm sensitization in IgE-mediated allergic disease in subjects with rhinoconjunctivitis, asthma, urticaria, anapylaxis, atopic eczema and food and drug allergy. This manuscript reviews the available evidence including Medline and Embase searches, abstracts of international allergy meetings and position papers from the world allergy literature. The recommended method of prick testing includes the appropriate use of specific allergen extracts, positive and negative controls, interpretation of the tests after 15 – 20 minutes of application, with a positive result defined as a wheal ≥3 mm diameter. A standard prick test panel for Europe for inhalants is proposed and includes hazel (Corylus avellana, alder (Alnus incana, birch (Betula alba, plane (Platanus vulgaris, cypress (Cupressus sempervirens, grass mix (Poa pratensis, Dactilis glomerata, Lolium perenne, Phleum pratense, Festuca pratensis, Helictotrichon pretense, Olive (Olea europaea, mugwort (Artemisia vulgaris, ragweed (Ambrosia artemisiifolia, Alternaria alternata (tenuis, Cladosporium herbarum, Aspergillus fumigatus, Parietaria, cat, dog, Dermatophagoides pteronyssinus, Dermatophagoides farinae, and cockroach (Blatella germanica. Standardization of the skin test procedures and standard panels for different geographic locations are encouraged worldwide to permit better comparisons for diagnostic, clinical and research purposes.

Habitat associations of three crayfish endemic to the Ouachita Mountain Ecoregion

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Dyer, Joseph J.; Brewer, Shannon K.

2018-01-01

Many crayfish are of conservation concern because of their use of unique habitats and often narrow ranges. In this study, we determined fine-scale habitat use by 3 crayfishes that are endemic to the Ouachita Mountains, in Oklahoma and Arkansas. We sampled Faxonius menae (Mena Crayfish), F. leptogonopodus (Little River Creek Crayfish), and Fallicambarus tenuis (Ouachita Mountain Crayfish) from wet and dry erosional channel units of 29 reaches within the Little River catchment. We compared channel-unit and microhabitat selection for each species. Crayfish of all species and life stages selected erosional channel units more often than depositional units, even though these sites were often dry. Accordingly, crayfish at all life stages typically selected the shallowest available microhabitats. Adult crayfish of all species and juvenile Little River Creek Crayfish selected patches of coarse substrate, and all crayfish tended to use the lowest amount of bedrock available. In general, we showed that these endemic crayfish used erosional channel units of streams, even when the channel units were dry. Conservation efforts that protect erosional channel units and mitigate actions that cause channel downcutting to bedrock would benefit these crayfish, particularly during harsh, summer drying periods.

Distribution and habitat ecology of the sorediate species of Menegazzia (Parmeliaceae, lichenized Ascomycota in Chile Distribución y ecología de las especies sorediosas de Menegazzia (Parmeliaceae, Ascomycota liquenizado en Chile

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JARLE W BJERKE

2003-03-01

Full Text Available ABSTRACT The taxonomy and ecology of the sorediate species of Menegazzia from the southernmost regions of Chile and Argentina and the South Atlantic Islands was recently published, only with sporadic reports from the more northern regions. In the present work the distribution patterns and habitat ecology of the sorediate species are discussed, with emphasis on the area north of 48º S. Eleven species are treated. Menegazzia subpertusa, an epiphyte of sclerophyll scrubs, is recorded from South America for the first time (Chile and Argentina. Menegazzia neozelandica has a disjunct distribution in Chile, with occurrences in Fray Jorge (Fourth Region of Chile and on Islas Juan Fernández, and along the coast south of latitude 38º S. Menegazzia kawesqarica and M. tenuis are most common in the southernmost part of Chile, but are also found at high altitudes at lower latitudes. Additional treated species are M. chrysogaster, M. fumarprotocetrarica, M. globulifera, M. magellanica, M. norsorediata, M. sanguinascens and M. wandae. Several of the sorediate species are early colonisers of newly developed substrates. They show variable occurrences along light and humidity gradients. Distribution maps and a revised key are presented.Recientemente se han publicado datos sobre la taxonomía y ecología de las especies sorediosas de Menegazzia representadas en las regiones más australes de Chile y Argentina e islas del Atlántico Sur, además de registros esporádicos en zonas ubicadas más al norte en Chile. En este trabajo se discuten los patrones de distribución y la ecología del hábitat de 11 especies sorediosas, con especial enfásis en aquellas que se desarrollan al norte de los 48º S. Menegazzia subpertusa, un epífito de arbustos esclerófilos, se registra por primera vez en América (Chile y Argentina. Menegazzia neozelandica tiene una distribución discontinua en Chile; ha sido recolectada en Fray Jorge (Cuarta Región de Chile, Islas Juan Fern

Macroepizoísmo em Libinia ferreirae (Crustacea, Brachyura, Majidae Macroepizoites on Libinia ferreirae (Crustacea, Brachyura, Majidae

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Vanessa C. Winter

2006-06-01

Full Text Available Um estudo de distribuição dos macroepizóicos foi realizado numa população do caranguejo-aranha Libinia ferreirae Brito Capello, 1871 proveniente do litoral dos estados do Paraná e de Santa Catarina. O material biológico foi obtido junto aos pescadores, e faz parte do rejeito de pesca. Os caranguejos foram mensurados e os macroepizóicos identificados e contados. Os seguintes macroepizóicos sésseis foram registrados: Calliactis tricolor (Lesueur, 1817 (Cnidaria; Actiniaria (Cnidaria; Arca sp. (Mollusca; Ostreidae (Mollusca; Acanthodesia tenuis (Desor, 1848 (Bryozoa; Cirripedia e duas espécies tubícolas de Gammaridea (Crustacea. Além destes organismos ocorreram dois tubos desabitados e quatro animais vágeis. A anêmona C. tricolor foi a espécie mais abundante e freqüente, sendo, provavelmente, utilizada como mecanismo de camuflagem pelo caranguejo. O macroepizoísmo em L. ferreirae está relacionado com a idade ou tamanho do caranguejo, tendo maior incidência naqueles mais velhos ou de maior porte. Entretanto, a densidade dos macroepizóicos por caranguejo se mantém em torno de três. Não há relação entre o macroepizoísmo e o sexo do hospedeiro; somente fêmeas ovígeras utilizam desse recurso mais freqüentemente do que as não-ovígeras. Devido à maior área de fixação, os macroepizóicos colonizam principalmente a carapaça do caranguejo, enquanto nos pereiópodos há predominância de Bryozoa.A study of the distribution of the macroepizoites was carried out on a population of the spider crab Libinia ferreirae Brito Capello, 1871 from the Southern Brazilian coast. Crabs were obtained from shrimps and fishes by-catch. They were measured, and their macroepizoites were identified and counted. The following sessile macroepizoites were registered: Calliactis tricolor (Lesueur, 1817 (Cnidaria; Actiniaria (Cnidaria; Arca sp. (Mollusca; Ostreidae (Mollusca; Acanthodesia tenuis (Desor, 1848 (Bryozoa; Cirripedia and two species

Mineralogical composition changes of postagrogenic soils under different plant communities.

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Churilin, Nikita; Chizhikova, Natalia; Varlamov, Evgheni; Churilina, Alexandra

2017-04-01

Plant communities play the leading role in transformation of soil. The need of studying former arable lands increases due to large number of abandoned lands in Russia. It is necessary to study mineralogical composition of soils involved into natural processes to understand the trends of their development after agricultural activities in the past. The aim of the study is to identify changes in mineralogical composition of soils under the influence of different plant communities. Soils were sampled in the south of Arkhangelsk region, Ustyansky district, near Akichkin Pochinok village. Soils are formed on clay moraine of Moscow glaciation. Soil profiles were dug on interfluve. We selected 4 plant communities on different stages of succession: upland meadow with domination of sod grasses (Phleum pratense, Agrostis tenuis), 16-year-old birch forest where dominants are herbaceous plants such as Poa sp., Chamerion angustiflium, Agrostis tenuis, 16-year-old spruce forest with no herbaceous vegetation and 70-year-old bilberry spruce forest with domination of Vaccinium myrtillus and Vaccinium vitis-idaea. To separate soil fractions mineral content. We noticed a clear differentiation of studied soils both in the content of fraction and composition of minerals. Mineralogical composition and major mineral phases correlation of profiles under 70 years and 16 years of spruce forests are different. Mineralogical content in upper part of profile under the young spruce is more differentiated than in old spruce forest: the amount of quartz and kaolinite increases in upper horizon, although in this case the overall pattern of profile formation of clay material during podzolization remains unchanged. There is more substantial desilting under the birch forest, compared with profile under the spruce of same age within top 50 cm. Under the meadow vegetation we've discovered differentiation in mineral composition. Upper horizons contain smectite phase and differ from the underlying

Acute ecotoxicology of natural oil and gas condensate to coral reef larvae.

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Negri, Andrew P; Brinkman, Diane L; Flores, Florita; Botté, Emmanuelle S; Jones, Ross J; Webster, Nicole S

2016-02-19

Risks posed by oil spills to coral reefs are difficult to evaluate, partially due to the absence of studies that adequately assess toxicity to relevant coral reef species. Here we experimentally tested the acute toxicity of condensate, representing a fraction of light crude oil, to coral (Acropora tenuis) and sponge (Rhopaloeides odorabile) larvae. The metamorphosis of coral larvae was inhibited at total petroleum aromatic hydrocarbon (TPAH) concentrations of water accommodated fractions (WAF) as low as 103 μg l(-1), similar to concentrations detected in seawater following large spills. The sensitivity of coral larvae increased by 40% when co-exposed to UV light that they might encounter in shallow reefal systems. Condensate WAF was more toxic to coral larvae than predicted by summing the toxicity of its main components (benzene, toluene, p-xylene and napthalene). In contrast, the sensitivity of sponge larvae to condensate WAF (>10,000 μg l(-1) TPAH) was far less than coral in the presence and absence of UV, but similar to that of other marine invertebrates. While these results highlight the relative sensitivity of coral larvae to oil, further research is needed to better understand and predict the impacts and risks posed by hydrocarbons to tropical reef systems.

Ostracoda (Arthropoda, Crustacea from the Riachuelo Formation, Sergipe-Alagoas Basin, Brazil, Upper Aptian-Albian

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Lucas Silveira Antonietto

2016-11-01

Full Text Available The Sergipe-Alagoas Basin has one of the most complete, exposed lithological successions of the Cretaceous period in the continental margin of Brazil. It captures several phases of the evolution of the South Atlantic Ocean, including rift, gulf and drift. The upper Aptian–Albian Riachuelo Formation corresponds to the first stages of the southern proto-Atlantic Ocean invasion in that basin. The present study reviews the taxonomic identification and ecology of 39 ostracod species of this formation, proposing a new genus – Gabonorygma gen. nov. – and three new species – Praebythoceratina deltalata sp. nov., Gabonorygma sergipana gen. et sp. nov. and Brachycythere smithsoniana sp. nov. Other taxa include Conchoecia? sp. 1, Cytherella sp. 1, C. besrineensis comb. nov., Cytherelloidea aff. globosa, C. btaterensis, Bairdoppilata sp. 1, Bairdoppilata sp. 2, B. comanchensis comb. nov., B. pseudoseptentrionalis, Robsoniella falklandensis, Cetacella sp. 1, Paracypris eniotmetos, Harbinia sinuata?, H. crepata, Liasina sp. 1, Praebythoceratina amsittenensis comb. nov., P. trinodosa comb. nov., Patellacythere sp. 1, P. shimonensis comb. nov., Xestoleberis? sp. 1, Xestoleberis? sp. 2, Apatocythere? sp. 1, Neocythere? aff. pseudovanveeni, N. (Physocythere tenuis, Aracajuia antiqua comb. nov., A. benderi, A. fragilis comb. nov., Eocytheropteron sp. 1, Metacytheropteron aff. minuta, Microceratina? sp. 1, M. azazoulensis, Veenia guianensis, Algeriana? sp. 1, Quasihermanites? sp. 1 and Sergipella viviersae.

Cyanobacteria-mediated phenylpropanoids and phytohormones in rice (Oryza sativa) enhance plant growth and stress tolerance.

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Singh, Dhananjaya P; Prabha, Ratna; Yandigeri, Mahesh S; Arora, Dilip K

2011-11-01

Phenylpropanoids, flavonoids and plant growth regulators in rice (Oryza sativa) variety (UPR 1823) inoculated with different cyanobacterial strains namely Anabaena oryzae, Anabaena doliolum, Phormidium fragile, Calothrix geitonos, Hapalosiphon intricatus, Aulosira fertilissima, Tolypothrix tenuis, Oscillatoria acuta and Plectonema boryanum were quantified using HPLC in pot conditions after 15 and 30 days. Qualitative analysis of the induced compounds using reverse phase HPLC and further confirmation with LC-MS/MS showed consistent accumulation of phenolic acids (gallic, gentisic, caffeic, chlorogenic and ferulic acids), flavonoids (rutin and quercetin) and phytohormones (indole acetic acid and indole butyric acid) in rice leaves. Plant growth promotion (shoot, root length and biomass) was positively correlated with total protein and chlorophyll content of leaves. Enzyme activity of peroxidase and phenylalanine ammonia lyase and total phenolic content was fairly high in rice leaves inoculated with O. acuta and P. boryanum after 30 days. Differential systemic accumulation of phenylpropanoids in plant leaves led us to conclude that cyanobacterial inoculation correlates positively with plant growth promotion and stress tolerance in rice. Furthermore, the study helped in deciphering possible mechanisms underlying plant growth promotion and stress tolerance in rice following cyanobacterial inoculation and indicated the less explored avenue of cyanobacterial colonization in stress tolerance against abiotic stress.

Monophyly of the species of Hepatozoon (Adeleorina: Hepatozoidae) parasitizing (African) anurans, with the description of three new species from hyperoliid frogs in South Africa.

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Netherlands, Edward C; Cook, Courtney A; Du Preez, Louis H; Vanhove, Maarten P M; Brendonck, Luc; Smit, Nico J

2017-12-04

Haemogregarines (Apicomplexa: Adeleiorina) are a diverse group of haemoparasites reported from almost all vertebrate classes. The most commonly recorded haemogregarines to parasitize anurans are species of Hepatozoon Miller, 1908. To date 16 Hepatozoon species have been described from anurans in Africa, with only a single species, Hepatozoon hyperolli (Hoare, 1932), infecting a member of the Hyperoliidae. Furthermore, only two Hepatozoon species are known from South African anurans, namely Hepatozoon theileri (Laveran, 1905) and Hepatozoon ixoxo Netherlands, Cook and Smit, 2014, from Amietia delalandii (syn. Amietia quecketti) and three Sclerophrys species, respectively. Blood samples were collected from a total of 225 individuals representing nine hyperoliid species from several localities throughout northern KwaZulu-Natal, South Africa. Twenty frogs from three species were found positive for haemogregarines, namely Afrixalus fornasinii (6/14), Hyperolius argus (2/39), and Hyperolius marmoratus (12/74). Based on morphological characteristics, morphometrics and molecular findings three new haemogregarine species, Hepatozoon involucrum Netherlands, Cook and Smit n. sp., Hepatozoon tenuis Netherlands, Cook and Smit n. sp. and Hepatozoon thori Netherlands, Cook and Smit n. sp., are described from hyperoliid hosts. Furthermore, molecular analyses show anuran Hepatozoon species to be a separate monophyletic group, with species isolated from African hosts forming a monophyletic clade within this cluster.

Phylogenetic relationships among zooxanthellae (Symbiodinium) associated to excavating sponges (Cliona spp.) reveal an unexpected lineage in the Caribbean.

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Granados, C; Camargo, C; Zea, S; Sánchez, J A

2008-11-01

Phylogenetic relationships of symbiotic dinoflagellate lineages, distributed in all tropical and subtropical seas, suggest strategies for long distance dispersal but at the same time strong host specialization. Zooxanthellae (Symbiodinium: Dinophyta), which are associated to diverse shallow-water cnidarians, also engage in symbioses with some sponge species of the genus Cliona. In the Caribbean, zooxanthellae-bearing Cliona has recently become abundant due to global warming, overfishing, and algae abundance. Using molecular techniques, the symbionts from five excavating species (Clionacaribbaea, C. tenuis, C. varians, C. aprica and C. laticavicola) from the southern and southwestern Caribbean were surveyed. Several DNA sequence regions were used in order to confirm zooxanthellae identity; 18S rDNA, domain V of chloroplast large subunit (cp23S), internal transcribed spacer 2 (ITS2), and ITS2 secondary structure. Sequence analyses corroborated the presence of three zooxanthellae clades: A, B, and G. Presence of clades A and B in common boring sponges of the Caribbean fit with the general pattern of the province. The discovery of clade G for the first time in any organism of the Atlantic Ocean leads us to consider this unusual finding as a phylogenetic relict through common ancestors of sponge clades or an invasion of the sponge from the Indo-Pacific.

Potential biocontrol actinobacteria: Rhizospheric isolates from the Argentine Pampas lowlands legumes.

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Solans, Mariana; Scervino, Jose Martin; Messuti, María Inés; Vobis, Gernot; Wall, Luis Gabriel

2016-11-01

Control of fungal plant diseases by using naturally occurring non-pathogenic microorganisms represents a promising approach to biocontrol agents. This study reports the isolation, characterization, and fungal antagonistic activity of actinobacteria from forage soils in the Flooding Pampa, Argentina. A total of 32 saprophytic strains of actinobacteria were obtained by different isolation methods from rhizospheric soil of Lotus tenuis growing in the Salado River Basin. Based on physiological traits, eight isolates were selected for their biocontrol-related activities such as production of lytic extracellular enzymes, siderophores, hydrogen cyanide (HCN), and antagonistic activity against Cercospora sojina, Macrophomia phaseolina, Phomopsis sp., Fusarium oxysporum, and Fusarium verticilloides. These actinobacteria strains were characterized morphologically, physiologically, and identified by using molecular techniques. The characterization of biocontrol-related activities in vitro showed positive results for exoprotease, phospholipase, fungal growth inhibition, and siderophore production. However, none of the strains was positive for the production of hydrogen cyanide (HCN). Streptomyces sp. MM140 presented the highest index for biocontrol, and appear to be promising pathogenic fungi biocontrol agents. These results show the potential capacity of actinobacteria isolated from forage soils in the Argentine Pampas lowlands as promising biocontrol agents, and their future agronomic applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects on the Growth and Survival of Eggs and Embryos of the California Grunion (Leuresthes tenuis) Exposed to Trace Levels of Tributyltin.

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1985-05-01

postfertilization exposure of grunion eggs to low doses of TBT has no effect on hatch success or notochord length at time of hatch. 2. No = exposure of...grunion eggs and sperm during fertilization and sub- sequent low-level dose incubation has no effect on fertilization, hatch suc- cess, or notochord ...clean glass vials for stor- -.- - age. Ten randomly selected larvae from each replicate were also measured for notochord length and examined for

Two new species of Quasithelazia Maplestone, 1932 (Nematoda: Acuariidae) from Malaysia, with an amended diagnosis and review of the genus.

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Mutafchiev, Yasen; Mariaux, Jean; Georgiev, Boyko B

2014-06-01

Quazithelazia rostrata n. sp. from Ceyx erithaca (L.) (type-host) and Alcedo euryzona Temminck (Coraciiformes, Alcedinidae) and Q. alata n. sp. from Enicurus ruficapillus Temminck (Passeriformes, Muscicapidae) are described from vicinities of Gombak Biological Station, Selangor, Malaysia; both species are parasitic under the koilin lining of the gizzard. Paratypes of Schistogendra pelargopsis Nandi, De & Majumdar, 1985, a parasite of Pelargopsis capensis (L.) (Alcedinidae) from India, are redescribed and the species is recognised as a junior synonym of the type-species of Quasithelazia, Q. tenuis Maplestone, 1932 (new synonymy), a species originally described from Halcyon smyrnensis (L.) (Alcedinidae) in India. An amended diagnosis of the genus Quasithelazia Maplestone, 1932 is proposed. Currently, this genus includes eight species occurring in the Old World, six of them parasitic in kingfishers (Alcedinidae) and two species parasitic in flycatchers (Muscicapidae). These include, inter alia, Q. halcyoni n. comb. for Viktorocara halcyoni Ryzhikov & Khokhlova, 1964 from Halcyon smyrnensis and H. pileata (Boddaert) in Vietnam and the Russian Far East, Q. microcordonis n. comb. for Rusguniella microcordonis Schmidt & Kuntz, 1971 from Halcyon coromanda major (Temminck & Schlegel) in Taiwan and Q. multipapillata n. comb. for Schistogendra multipapillata Zhang, 1993 from Tarsiger cyanurus (Pallas) (Muscicapidae) in China. Comparative morphological data for Quasithelazia spp. are presented. Schistogendra oligopapillata Zhang & An, 2002 from domestic ducks in China is considered a species incertae sedis.

Microscopic and Molecular Tracing of Cryptosporidium Oocysts: Identifying a Possible Reservoir of Infection in Red Grouse

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David Baines

2017-11-01

Full Text Available Infection by Cryptosporidium baileyi causes respiratory cryptosporidiosis in red grouse Lagopus lagopus scotica. First diagnosed in 2010, it has since been detected across half of moors managed for grouse shooting in northern England. We hypothesised that contaminated grouse faeces within communal trays visited by grouse containing grit coated with flubendazole, provided to control Trichostrongylus tenuis parasites of grouse, is a reservoir of infection. To establish the basis to this hypothesis, contents of 23 trays from a grouse moor were examined for Cryptosporidium oocysts. Contents were subjected to Immuno Magnetic Separation oocyst concentration techniques prior to examination by Immuno Fluorescence Antibody Test microscopy and molecular analysis on the 18S rRNA gene. Seven of 13 (54% grit trays known to be used by infected grouse were positive for Cryptosporidium by IMS-IFAT, compared to two of 10 (20% random background trays. Ten of the 13 (77% trays used by infected birds amplified positive for Cryptosporidium by Polymerase Chain Reaction and three of the 10 (30% random trays. All PCR amplified products sequenced matched with C. baileyi, with C. parvum also present in one tray. These data suggest that trays used to “worm” grouse may act as reservoirs of Cryptosporidium infection and their future design may need to be reconsidered to minimise contamination.

Micromorphological study (ultrastructure of lamina surface, seeds, ultrasculpture of pollen grains of Gladiolus L. species (Iridaceae Juss. of Ukrainian flora

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Zhygalova Svitlana L.

2014-12-01

Full Text Available Micro-morphological characteristics of the four Gladiolus L. species of the Ukrainian flora (G. imbricatus L., G. italicus Mill., G. palustris Gaudin and G. tenuis M. Bieb. as regards leaves, seeds and pollens are presented with this investigation in a detailed way. An examination of the surface structure of the leaves, seeds and pollen grains of the Gladiolus species indicates that the characteristics of the ultrastructure of leaves and of pollen grains are not diagnostic for distinguishing species, but they could be important at genus level (leaves: features such as being amphistomatic, having the same quantity of immersed stomata on both surfaces and having a high stomata index, the presence and localisation of papillae, the shape of epidermal cells; pollen grains: monosulcate type with two operculums. However, the type of surface ultrastructure of the seed coat is a diagnostic feature as at genus level so for species. It can be mentioned that propose the use of features such as the shape and position of the cicatricle, the type of cuticle, the shape and boundaries of cells of testa, and the anticlinal cell walls as diagnostic features at genera level. The shape of seeds, the presence and disposition of wing, the level of the periclinal cell walls of the seed coat and types of relief are additional diagnostic features for distinguishing of Gladiolus species.

Residual Acute Toxicity of Some Modern Insecticides Toward Two Mirid Predators of Tomato Pests.

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Wanumen, Andrea C; Carvalho, Geraldo A; Medina, Pilar; Viñuela, Elisa; Adán, Ángeles

2016-03-31

The successful integration of chemical and biological control strategies for crop pests depends on a thorough evaluation of the effects of pesticides on the natural enemies of pests. A case-by-case review is difficult to achieve because of the many combinations of pests, natural enemies, and crops that need to be tested. Within this framework, we tested and compared seven insecticides representative of four different modes of action (MoAs) groups on closely related predators (Miridae): flubendiamide, spirotetramat, metaflumizone, and sulfoxaflor onNesidiocoris tenuisReuter and flubendiamide, spiromesifen, indoxacarb, and imidacloprid onMacrolophus basicornis(Stal). We follow the standardized methodology of the International Organization for Biological Control, a sequential testing exposure scheme. The lethal effect of each insecticide was evaluated in adults after three days of contact with treated surfaces in the laboratory, extended laboratory, and semifield tests (inert substrate, tomato leaves, and tomato plant as the treated surface, respectively). Flubendiamide, spiromesifen, and spirotetramat were classified as harmless (class 1), metaflumizone was slightly harmful (class 2) but persistent, indoxacarb was harmless (class 1), and sulfoxaflor and imidacloprid were toxic (class 4) and exhibited a long residual activity. Our results suggest similarities in the acute toxicities of insecticides from the same MoA group on related species of natural enemies. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

In vitro investigating of anticancer activity of focuxanthin from marine brown seaweed species

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M. Karkhane Yousefi

2018-01-01

Full Text Available Breast cancer is the most common cancer type among women all over the world. Chemotherapy is the use of anticancer medicines for treating cancer but it has many side effects and cells may become resistant to these chemical medicines. Therefore, finding new compounds of natural origin could be a promising solution to this problem. The aim of the current study was to evaluate anticancer activity of fucoxanthin which is the most important carotenoid found in the marine brown seaweeds and diatoms. fucoxanthin has many properties (antioxidant, antibacterial, anticancer, antiobesity, anti-inflammatory and etc. due to its unique structure. Samples with different concentrations (10, 25 and 50 µg/ml and at various incubation times were collected (6, 24 and 48 hours from four different species (Padina tenuis, Colpomenia sinuosa, Iyengaria stellate and Dictyota indica of brown seaweeds from Qeshm Island, Persian Gulf. Moreover, the anticancer activity of fucoxanthin-containing extracts on breast cancer cells line and normal human skin fibroblast cells line was assessed by MTT [3-(4,5-dimethylthiazolyl-2,5-diphenyl-tetrazolium bromide] assay to specify the cytotoxic effects. The results showed that fucoxanthin extract from Dictyota. indica at 24-hour treatment and 50 µg/ml concentration has the most effective anticancer activity on the breast cancer cells line, without toxic effects to the normal cells. According to the obtained results, it seems that Dictyota. Indica is a good candidate for further analysis and can be introduced to the food and pharmaceutical industries.

Synthesis, characterization, spectroscopic properties and DFT study of a new pyridazinone family

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Arrue, Lily; Rey, Marina; Rubilar-Hernandez, Carlos; Correa, Sebastian; Molins, Elies; Norambuena, Lorena; Zarate, Ximena; Schott, Eduardo

2017-11-01

Nitrogen compounds are widely investigated due to their pharmacological properties such as antihypertensive, antinociceptive, antibacterial, antifungal, analgesic, anticancer and inhibition activities and lately even as pesticide. In this context, we present the synthesis of new compounds: (E)-6-(3,4-dimethoxyphenyl)-3-(3-(3,4-dimethoxyphenyl)acryloyl)-1-(4-R-phenyl)- 5,6-dihydropyridazin-4(1H)-one (with R = sbnd H(1), -Cl(2), -Br(3), sbnd I(4) and sbnd COOH(5)) that was carried out by reaction of (1E, 6E)-1,7-bis(3,4-dimethoxyphenyl)hepta-1,6-diene-3,5-dione with a substituted phenylamine with general formula p-R-C6H4sbnd NH2 (R = sbnd H (1), sbnd Cl (2), -Br(3), sbnd I(4) and sbnd COOH(5)). This is the first synthesis report of a pyridazinone using as precursors a curcuminoid derivative and a diazonium salt formed in situ. All compounds were characterized by EA, FT-IR, UV-Vis, Emission,1H- and13C-NMR spectroscopy and the crystalline and molecular structure of 4 was solved by X-rays diffraction method. DFT and TD-DFT quantum chemical calculations were also employed to characterize the compounds and provide a rational explanation to the spectroscopic properties. To assess the biological activity of the systems, we focused on pesticide tests on compound 2, which showed an inhibitory effect in plant growth of Agrostis tenuis Higland.

Effects of N2-O2 and CO2-O2 tensions on growth of fungi isolated from damaged flue-cured tobacco.

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Yang, H; Lucas, G B

1970-02-01

Ten fungi, Aspergillus niger, A. flavus, A. ochraceus, A. ruber, A. repens, A. amstelodami, Alternaria tenuis, Penicillium brevi-compactum, Cladosporium herbarum, and Chaetomium dolicotrichum, were isolated from moldy flue-cured tobacco and grown in various mixtures of N(2)-O(2) or CO(2)-O(2). A 1 to 5% concentration of O(2) in an N(2) atmosphere caused the greatest change in growth of the nine species, and a 10 to 20% concentration of O(2) for A. flavus. All species, except A. amstelodami and A. ruber, grew faster in air than in mixtures containing 10% O(2). High O(2) concentrations generally inhibited furrow production in the mycelial mats. In an atmosphere of 5 to 40% O(2) in the N(2) atmosphere, furrows formed in mycelial mats between 5 and 40% O(2) in the species except for A. ruber, A. repens, and A. amstelodami, which produced none in any concentration. As O(2) decreased below 20%, spore production was progressively decreased, colony color faded to white, and cleistothecia formation was suppressed. In CO(2)-O(2) mixtures radial growth of all species increased with each quantitative decrease of CO(2). All species except A. niger grew faster in air than in 10% CO(2). In contrast to N(2)-O(2) mixtures, the fungi formed furrows, sporulation and cleistothecial formation were suppressed, and colony color changed to white in higher O(2) concentrations.

Effects of N2-O2 and CO2-O2 Tensions on Growth of Fungi Isolated from Damaged Flue-Cured Tobacco 1

Science.gov (United States)

Yang, H.; Lucas, G. B.

1970-01-01

Ten fungi, Aspergillus niger, A. flavus, A. ochraceus, A. ruber, A. repens, A. amstelodami, Alternaria tenuis, Penicillium brevi-compactum, Cladosporium herbarum, and Chaetomium dolicotrichum, were isolated from moldy flue-cured tobacco and grown in various mixtures of N2-O2 or CO2-O2. A 1 to 5% concentration of O2 in an N2 atmosphere caused the greatest change in growth of the nine species, and a 10 to 20% concentration of O2 for A. flavus. All species, except A. amstelodami and A. ruber, grew faster in air than in mixtures containing 10% O2. High O2 concentrations generally inhibited furrow production in the mycelial mats. In an atmosphere of 5 to 40% O2 in the N2 atmosphere, furrows formed in mycelial mats between 5 and 40% O2 in the species except for A. ruber, A. repens, and A. amstelodami, which produced none in any concentration. As O2 decreased below 20%, spore production was progressively decreased, colony color faded to white, and cleistothecia formation was suppressed. In CO2-O2 mixtures radial growth of all species increased with each quantitative decrease of CO2. All species except A. niger grew faster in air than in 10% CO2. In contrast to N2-O2 mixtures, the fungi formed furrows, sporulation and cleistothecial formation were suppressed, and colony color changed to white in higher O2 concentrations. PMID:5461786

Helminth community structure in two species of arctic-breeding waterfowl

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C.L. Amundson

2016-12-01

Full Text Available Climate change is occurring rapidly at high latitudes, and subsequent changes in parasite communities may have implications for hosts including wildlife and humans. Waterfowl, in particular, harbor numerous parasites and may facilitate parasite movement across broad geographic areas due to migratory movements. However, little is known about helminth community structure of waterfowl at northern latitudes. We investigated the helminth communities of two avian herbivores that breed at high latitudes, Pacific black brant (Branta bernicla nigricans, and greater white-fronted geese (Anser albifrons, to examine effects of species, geographic area, age, and sex on helminth species richness, aggregation, prevalence, and intensity. We collected 83 and 58 black brant and white-fronted geese, respectively, from Arctic and Subarctic Alaska July–August 2014. We identified 10 known helminth species (Amidostomum anseris, Amidostomum spatulatum, Drepanidotaenia lanceolata, Epomidiostomum crami, Heterakis dispar, Notocotylus attenuatus, Tetrameres striata, Trichostrongylus tenuis, Tschertkovilepis setigera, and Wardoides nyrocae and 1 previously undescribed trematode. All geese sampled were infected with at least one helminth species. All helminth species identified were present in both age classes and species, providing evidence of transmission at high latitudes and suggesting broad host susceptibility. Also, all but one helminth species were present at both sites, suggesting conditions are suitable for transmission across a large latitudinal/environmental gradient. Our study provides important baseline information on avian parasites that can be used to evaluate the effects of a changing climate on host-parasite distributions.

Fermentation of mixed glucose-xylose substrates by engineered strains of Saccharomyces cerevisiae: role of the coenzyme specificity of xylose reductase, and effect of glucose on xylose utilization

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Klimacek Mario

2010-03-01

Full Text Available Abstract Background In spite of the substantial metabolic engineering effort previously devoted to the development of Saccharomyces cerevisiae strains capable of fermenting both the hexose and pentose sugars present in lignocellulose hydrolysates, the productivity of reported strains for conversion of the naturally most abundant pentose, xylose, is still a major issue of process efficiency. Protein engineering for targeted alteration of the nicotinamide cofactor specificity of enzymes catalyzing the first steps in the metabolic pathway for xylose was a successful approach of reducing xylitol by-product formation and improving ethanol yield from xylose. The previously reported yeast strain BP10001, which expresses heterologous xylose reductase from Candida tenuis in mutated (NADH-preferring form, stands for a series of other yeast strains designed with similar rational. Using 20 g/L xylose as sole source of carbon, BP10001 displayed a low specific uptake rate qxylose (g xylose/g dry cell weight/h of 0.08. The study presented herein was performed with the aim of analysing (external factors that limit qxylose of BP10001 under xylose-only and mixed glucose-xylose substrate conditions. We also carried out a comprehensive investigation on the currently unclear role of coenzyme utilization, NADPH compared to NADH, for xylose reduction during co-fermentation of glucose and xylose. Results BP10001 and BP000, expressing C. tenuis xylose reductase in NADPH-preferring wild-type form, were used. Glucose and xylose (each at 10 g/L were converted sequentially, the corresponding qsubstrate values being similar for each strain (glucose: 3.0; xylose: 0.05. The distribution of fermentation products from glucose was identical for both strains whereas when using xylose, BP10001 showed enhanced ethanol yield (BP10001 0.30 g/g; BP000 0.23 g/g and decreased yields of xylitol (BP10001 0.26 g/g; BP000 0.36 g/g and glycerol (BP10001 0.023 g/g; BP000 0.072 g/g as compared

Condensed Tannin Concentrations of Three Lotus Species Grown in Different Environments Contenido de Taninos Condensados en Germoplasma de Tres Especies del Género Lotus en Diferentes Ambientes

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Hernán Acuña

2008-03-01

Full Text Available Condensed tannins (CT present in Lotus spp., depending on their concentration in the plant, can prevent bloating and improve protein absorption in ruminants. With the objective to know the variability of this characteristic, the CT concentration (% dry matter basis was determined by the butanol-HCl procedure in 13 cultivars of Lotus corniculatus L. (Lc introduced from North and South America and Oceania, 11 accessions of Lotus tenuis Waldst. & Kit. ex Willd. (Lt, and 22 accessions of Lotus uliginosus Schkuhr (Lu collected in Chile, from 32° to 38° S and 36° to 46° S, respectively. The field experiments, with two randomized complete blocks, were established in autumn 1998, in five different environments in the central-southern zone of Chile (clay soil, sandy soil, and three volcanic soils with different levels of water availability. The herbage sampling was conducted in spring-summer 1999-2000, when the plants were in full flowering. Significant differences between cultivars or accessions were found within each site, in total CT and/or in extractable or protein or fiber bound fractions of CT concentrations. The Lc and Lu genotypes showed high variability, with a range of 4.7 to 8.7% and 6.3 to 11.0%, and means of 6.1 and 8.2%, respectively, of total CT. The Lt general mean was 4.8%, considerably higher than the figures reported in the literature, and had low variability. This information will contribute to select genotypes for the improvement of this species by selection and breedingLos taninos condensados (TC presentes en Lotus spp ., dependiendo de su concentración en la planta, pueden evitar el meteorismo y favorecer la absorción de proteína en rumiantes. Con el objetivo de conocer la variabilidad de esta característica se determinó por el método del butanol-HCl la concentración (% base materia seca de TC en 13 cultivares de Lotus corniculatus L. (Lc introducidos de Norteamérica, Sudamérica y Oceanía, 11 accesiones de Lotus

Altitudinal zonation among lizards of the genus Liolaemus: questions answered and unanswered questions Zonación altitudinal en lagartijas del género Liolaemus: preguntas respondidas y pendientes

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JOHN H. CAROTHERS

2001-06-01

Full Text Available We review factors influencing Liolaemus distributions in the central Chilean Andes and suggest areas of future research. Our previous studies reveal that lizard parasites (ectoparasitic mites and ticks, and the endoparasite Plasmodium do not set Liolaemus altitudinal limits. Thermal tolerances do not appear to limit altitudinal distributions, although cold ambient temperatures dictate that only live-bearing species can occur above 2,400 m elevation. Three Liolaemus species specialize on elevationally restricted microhabitats. Liolaemus tenuis is found exclusively in or at the base of trees, which are typically below 1,800 m. Liolaemus leopardinus specializes on large rocky outcrops found at high altitudes. Liolaemus monticola uses smaller rocks: oviparity set its upper distributional limit on two transects, but on one transect this lizard and its rocky habitat virtually disappeared above 1,500 m. Interspecific competition among Liolaemus appeared unrelated to elevational distribution. We found no instances of parapatric distributions among pairs of Liolaemus species having similar niche requirements. Other researchers have found that predation does not correlate with elevation: its role in determining lizard species distributions depends on both predator and prey identities. We conclude that factors setting distributional limits of Liolaemus species vary depending on individual circumstances in time and space: where physiology may be relevant on one transect, preferred microhabitat availability may be important in anotherRevisamos los factores que influyen sobre las distribuciones de Liolaemus en los Andes del centro de Chile y sugerimos futuras avenidas de investigación. Nuestros estudios previos revelan que los parásitos (garrapatas y ácaros ectoparásitos y el endoparásito Plasmodium no influyen sobre los límites altitudinales de Liolaemus. Las tolerancias térmicas tampoco parecen limitar dichas distribuciones altitudinales, aunque las

Application of monoclonal antibodies in functional and comparative investigations of heavy-chain immunoglobulins in new world camelids.

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Daley, L P; Gagliardo, L F; Duffy, M S; Smith, M C; Appleton, J A

2005-03-01

Of the three immunoglobulin G (IgG) isotypes described to occur in camelids, IgG2 and IgG3 are distinct in that they do not incorporate light chains. These heavy-chain antibodies (HCAbs) constitute approximately 50% of the IgG in llama serum and as much as 75% of the IgG in camel serum. We have produced isotype-specific mouse monoclonal antibodies (MAbs) in order to investigate the roles of HCAbs in camelid immunity. Seventeen stable hybridomas were cloned, and three MAbs that were specific for epitopes on the gamma chains of llama IgG1, IgG2, or IgG3 were characterized in detail. Affinity chromatography revealed that each MAb bound its isotype in solution in llama serum. The antibodies bound to the corresponding alpaca IgGs, to guanaco IgG1 and IgG2, and to camel IgG1. Interestingly, anti-IgG2 MAbs bound three heavy-chain species in llama serum, confirming the presence of three IgG2 subisotypes. Two IgG2 subisotypes were detected in alpaca and guanaco sera. The MAbs detected llama serum IgGs when they were bound to antigen in enzyme-linked immunosorbent assays and were used to discern among isotypes induced during infection with a parasitic nematode. Diseased animals, infected with Parelaphostrongylus tenuis, did not produce antigen-specific HCAbs; rather, they produced the conventional isotype, IgG1, exclusively. Our data document the utility of these MAbs in functional and physiologic investigations of the immune systems of New World camelids.

Systematics of the southern African genus Ixia (Iridaceae: Crocoideae: 4. Revision of sect. Dichone

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P. Goldblatt

2012-12-01

Full Text Available The southern African genus Ixia L. comprises ± 90 species from the winter-rainfall zone of the subcontinent. Ixia sect. Dichone (Salisb. ex Baker Goldblatt & J.C.Manning, one of four sections in the genus and currently including 10 species and three varieties, is distinguished by the following floral characters: lower part of the perianth tube filiform and tightly clasping the style; filaments not decurrent; upper part of the perianth tube short to vestigial; style branches involute-tubular and stigmatic only at the tips; and so-called subdidymous anthers. We review the taxonomy of the section, providing complete descriptions and distribution maps, and a key to the species. I. amethystina Manning & Goldblatt is recognized to be a later synonym of I. brevituba G.J.Lewis. Most collections currently included under that name represent another species, here described as I. rigida. We recognize five additional species in the section: early summer-blooming I. altissima from the Cedarberg; I. bifolia from the Caledon District; I. flagellaris, a stoloniferous species from the Cedarberg; I. simulans from the western Langeberg; and I. tenuis from the Piketberg. We also raise to species rank I. micrandra var. confusa and var. minor, as I. confusa and I. minor respectively. Foliar and associated floral variation in the widespread I. scillaris has led us to recognize two new subspecies among its northern populations, broad leaved subsp. latifolia and the dwarfed, smaller flowered subsp. toximontana; subsp. scillaris is restricted to the immediate southwestern Cape, from Darling to Somerset West. Sect. Dichone now has 17 species and two subspecies.

Epizootiologic studies on filarioids of the raccoon

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Herman, C.M.; Price, D.L.

1965-01-01

Filarioid worms (Dirofilaria immitis, D. tenuis, Dipetalonema procyonis, and D. llewellyni) were discovered in raccoons (Procyon lotar) in Maryland. Raccoons were trapped in lowland, upland, and agricultural-residential areas, which were further classified as stream borders, poorly drained, and well drained. Data on incidence of D. llewellyni were analyzed on basis of host distribution within these areas to indicate type of habitat in which one might seek the vector. It was concluded that exposure takes place in the spring of the year. The arthropod found associated most often with the raccoon in spring was Ixodes texanus. Larvae of this tick which were fed on infected raccoons presented no evidence of development of the microfilariae. Feeding experiments were also conducted with mosquitoes: Aedes aegypti, A. canadensis, A. sollicitans, A. triseriatus, A. vexans, Culex pipiens, Anopheles punctipennis, and A. quadrimaculatus. Although microfilariae remained alive and active in the gut contents of all these mosquitoes for 2 days, only in Aedes aegypti did they enter the hemocele, but no developmental changes were noted and all microfilariae were dead by the eighth day. Although the intermediate host of D. llewellyni was not determined, evaluation of the accumulated data provides criteria for seeking the vector. It appeared unlikely that exposure of the raccoons took place in the den or that the filarioids were transmitted by an ectoparasite commonly found in raccoon dens. The data suggest that the vector is available only early in spring, although there are infected raccoons throughout the year. Prevalence in juveniles was 21 percent; in subadults, 64 percent; in adults, 87 percent.

Phytoplankton community and limnology of Chatla floodplain wetland of Barak valley, Assam, North-East India

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Sultana Laskar H.

2013-09-01

Full Text Available Phytoplankton diversity was investigated over a period of two years (2006 to 2008 in Chatla floodplain wetland in Barak valley, Assam, North-East India. Site 1 and site 2 are two inlets and site 3 is a lentic system associated with vegetation cover of Calamus tenuis and Baringtonia acutangula. The floodplain has a unique hydrology because of the presence of different types of habitats (inlets, fisheries, beels and outlets which maintains a network among the floodplains, rivers and streams. Phytoplankton community composition, density and diversity were studied in relation to environmental variables. All the variables were estimated by following standard methods. Phytoplankton was collected by plankton net and quantitative estimation was made by using Sedgwick Rafter counting cell. Phytoplankton community comprised 53 taxa represented by Chlorophyceae (31, Cyanophyceae (11, Bacillariophyceae (7, Euglenophyceae (1 and Dinophyceae (3. Phytoplankton taxa was dominated by Volvox sp., Nostoc sp., Eunotia sp., Navicula sp., Euglena spp. and density was found highest in site 3 and lowest in site 1. Shannon diversity index (H′ for phytoplankton community varied between 2.4 to 2.65 indicating fairly high species diversity. The varying magnitude of correlationship among environmental variables and phytoplankton species density as shown by Canonical correspondence analysis (CCA indicated that some of the environmental variables (water temperature, transparency, rainfall, nitrate and ammonia are the driving factors for governing the phytoplankton species assemblages in Chatla floodplain wetland. Fluctuation of phytoplankton density and community composition in different habitats indicated various niche apportionment as well as anthropogenic influences.

Ecologie et biologie de la conservation des métallophytes: le cas de Crepidorhopalon perenniset C. tenuis (Scrophulariaceae) des sols cupro-cobaltifères du Katanga

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Faucon, Michel-Pierre

2009-01-01

La province du Katanga est connue pour ses affleurements naturels de roches riches en cuivre et en cobalt. Plus d’une centaine de « collines de cuivre », isolées géographiquement et écologiquement possèdent une flore très originale qui comprend plus de 600 espèces dont 32 endémiques. Les métallophytes du Katanga sont des plantes fascinantes aux points de vue écologique, biogéographique, physiologique et évolutif. Elles restent très peu étudiées et leur conservation est très problématique comp...

Occurrence and identification of the etiologic agents of plant diseases in cactus (Opuntia ficus-indica Mill. in the semi-arid region of Paraiba

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Anne Evelyne Franco de Souza

2010-01-01

Full Text Available Cactus forage (Opuntia ficus-indica Mill., intensely cultivated in dry regions of northeast Brazil, although well adapted to the harsh semi-arid climate is affected by major problems such as pests and diseases, responsible for significant losses in production. This study aimed to investigate the occurrence and diversity of the etiologic agents of diseases of cactus cultivated in 38 municipalities in the semi-arid region of Paraiba. The analyses were conducted and processed at the Laboratory of Phytopathology of the Centro de Ciências Agrárias da Universidade Federal da Paraíba, in Areia - PB. Starting from sick cladodes isolations, multiplications and identifications of the found microorganisms were made. The identification of the microorganisms was achieved through observations of the macro and micromorphological characteristics of the cultures and tests of Gram and pathogenicity. Great incidence and diversity of microorganisms was verified in the cacti researched, but the highest occurrence was mainly that of fungus. The fungi of widest occurrence were: Scytallidium lignicola, Alternate tenuis, Macrophomina phaseolina, Cladosporium cladosporides, Lasiodiplodia theobromae, Fusarium oxysporum f. sp. opuntiarum, Curvularia lunata, Aspergillus niger, Nigrospora sphaerica, Colletotrichum gloeosporioides, Exserohilum turcicum, Pestalotia pitospora, Rhizopus stolonifer, Rhizoctonia solani and Sphaceloma protearum. A bacterium was also detected that was suspected to belong to the Erwinia sp. strain. Satisfaction of the Postulates of Koch proved the infectious nature of the detected microorganisms. High occurrence of the fungus S. lignicola, an agent of scale rot disease in 100% of the places researched, was observed. This fact is of great concern, since the progression of the disease can cause significant losses in production.

FLORESCIMENTO INDUZIDO DA JUREMA PRETA PARA FORNECER PÓLEN À ABELHA MELÍFERA NA ESTIAGEM DA CAATINGA

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ALINE DOS SANTOS SILVA

2015-01-01

Full Text Available The aim of this study was to investigate the possibility of increasing pollen supply to honey bees (Apis mellifera during the dry season in Caatinga (shrub vegetation of NE Brazil by inducing Mimosa tenui-flora to bloom. The work was carried out from August to December 2012 in Altamira Apícola Apiaries, situat-ed at Limoeiro do Norte – Ceará, Brazil. The experiment comprised three phases: Phase 1 – the amount of wa-ter needed to induce the blooming of Mimosa tenuiflora (T0L, T250L, T500L, T750L and T1000L; Phase 2 – Floral biology and flower visitors; Phase 3 – pollen harvested by the colonies and percentage of M. tenuiflora in the honey bee diet by sampling and comparing pollen loads from colonies placed 20m with those more than 3km away from the induced plants. Results of the Phase 1 showed that the treatments 3, 4 and 5 induced blooming, and T1000L produced a greater number of inflorescences (p <0.05. Blooming reached its peak eight days after induction. Hymenoptera represented more than 95% of floral visitors with Apis mellifera, Trigona spinipes and Melipona subnitida as the most frequent bee species. Palynological analyses carried out in phase 3 showed a significant (p<0,05 increment in pollen collection and the participation of M. tenuiflora pollen in the diet of colonies situated 20 meters from the induced plants. Induction of flowering Mimosa tenuiflora increased the supply and collection of pollen by bees in the critical period of the year, minimizing the effect of drought on the colonies.

Effects of herbivore exclusion and nutrient enrichment on coral reef macroalgae and cyanobacteria

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Thacker, R.; Ginsburg, D.; Paul, V.

2001-05-01

Although phase shifts on coral reefs from coral-dominated to algal-dominated communities have been attributed to the effects of increased nutrient availability due to eutrophication and reduced herbivore abundance due to overfishing and disease, these factors have rarely been manipulated simultaneously. In addition, few studies have considered the effects of these factors on benthic, filamentous cyanobacteria (blue-green algae) as well as macroalgae. We used a combination of herbivore-exclusion cages and nutrient enrichment to manipulate herbivore abundance and nutrient availability, and measured the impacts of these treatments on macroalgal and cyanobacterial community structure. In the absence of cages, surface cover of the cyanobacterium Tolypothrix sp. decreased, while surface cover of the cyanobacteria Oscillatoria spp. increased. Cyanobacterial cover decreased in partial cages, and Tolypothrix sp. cover decreased further in full cages. Lower cyanobacterial cover and biomass were correlated with higher macroalgal cover and biomass. Dictyota bartayresiana dominated the partial cages, while Padina tenuis and Tolypiocladia glomerulata recruited into the full cages. Palatability assays demonstrated that herbivore-exclusion shifted macroalgal species composition from relatively unpalatable to relatively palatable species. Nutrient enrichment interacted with herbivore exclusion to increase the change in cover of D. bartayresiana in the uncaged and fully caged plots, but did not affect the final biomass of D. bartayresiana among treatments. Nutrient enrichment did not significantly affect the cover or biomass of any other taxa. These results stress the critical role of herbivory in determining coral reef community structure and suggest that the relative palatabilities of dominant algae, as well as algal growth responses to nutrient enrichment, will determine the potential for phase shifts to algal-dominated communities.

Amino Acids Sequence Based in Silico Analysis of RuBisCO (Ribulose-1,5 Bisphosphate Carboxylase Oxygenase Proteins in Some Carthamus L. ssp.

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Emre SEVİNDİK

2017-06-01

Full Text Available RuBisCO is an important enzyme for plants to photosynthesize and balance carbon dioxide in the atmosphere. This study aimed to perform sequence, physicochemical, phylogenetic and 3D (three-dimensional comparative analyses of RuBisCO proteins in the Carthamus ssp. using various bioinformatics tools. The sequence lengths of the RuBisCO proteins were between 166 and 477 amino acids, with an average length of 411.8 amino acids. Their molecular weights (Mw ranged from 18711.47 to 52843.09 Da; the most acidic and basic protein sequences were detected in C. tinctorius (pI = 5.99 and in C. tenuis (pI = 6.92, respectively. The extinction coefficients of RuBisCO proteins at 280 nm ranged from 17,670 to 69,830 M-1 cm-1, the instability index (II values for RuBisCO proteins ranged from 33.31 to 39.39, while the GRAVY values of RuBisCO proteins ranged from -0.313 to -0.250. The most abundant amino acid in the RuBisCO protein was Gly (9.7%, while the least amino acid ratio was Trp (1.6 %. The putative phosphorylation sites of RuBisCO proteins were determined by NetPhos 2.0. Phylogenetic analysis revealed that RuBisCO proteins formed two main clades. A RAMPAGE analysis revealed that 96.3%-97.6% of residues were located in the favoured region of RuBisCO proteins. To predict the three dimensional (3D structure of the RuBisCO proteins PyMOL was used. The results of the current study provide insights into fundamental characteristic of RuBisCO proteins in Carthamus ssp.

The community structure and seasonal dynamics of plankton in Bange Lake, northern Tibet, China

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Zhao, Wen; Zhao, Yuanyi; Wang, Qiaohan; Zheng, Mianping; Wei, Jie; Wang, Shan

2016-11-01

The seasonal variations in biomass, abundance, and species composition of plankton in relation to hydrography were studied in the saline Bange Lake, northern Tibet, China. Sampling was carried out between one to three times per month from May 2001 to July 2002. Salinity ranged from 14 to 146. The air and water temperature exhibited a clear seasonal pattern, and mean annual temperatures were approximately 4.8°C and 7.3°C, respectively. The lowest water temperature occurred in winter from December to March at -2°C and the highest in June and July at 17.7°C. Forty-one phytoplankton taxa, 21 zooplankton, and 5 benthic or facultative zooplankton were identified. The predominant phytoplankton species were Gloeothece linearis, Oscillatoria tenuis, Gloeocapsa punctata, Ctenocladus circinnatus, Dunaliella salina, and Spirulina major. The predominant zooplankton species included Holophrya actra, Brachionus plicatilis, Daphniopsis tibetana, Cletocamptus dertersi, and Arctodiaptomus salinus. The mean annual total phytoplankton density and biomass for the entire lake were 4.52×107 cells/L and 1.60 mg/L, respectively. The annual mean zooplankton abundance was 52, 162, 322, and 57, 144 ind./L, in the three sublakes. The annual mean total zooplankton biomass in Lakes 1-3 was 1.23, 9.98, and 2.13 mg/L, respectively. The annual mean tychoplankton abundances in Bg1, 2, and 3 were 47, 67, and 654 ind./L. The annual mean tychoplankton biomass was 2.36, 0.16, and 2.03 mg/L, respectively. The zooplankton biomass (including tychoplankton) in the lake was 9.11 mg/L. The total number of plankton species in the salt lake was significantly negatively correlated with salinity.

Durabilidade natural do estipe de pupunha (Bactris gasipaes Kunth, Arecaceae II: insetos Natural durability of Bactris gasipaes Kunth (peach palm, Arecaceae stipe II: insects

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Raimunda Liege Souza de Abreu

2004-09-01

Full Text Available Neste trabalho estão apresentados os resultados da durabilidade natural do estipe (madeira de Bactris gasipaes Kunth (pupunha, quando submetido ao ataque de insetos xilófagos, em ensaios em ambiente florestal e urbano. Foram utilizados dez palmeiras, cinco com espinhos e cinco sem espinhos, de plantios da Fazenda Experimental da Universidade Federal do Amazonas, localizada no km 40 da rodovia Manaus-Boa Vista (BR 174. De cada uma das palmeiras foram cortados três discos de aproximadamente 30 cm de espessura, retirados da base, do meio e do topo. No ambiente florestal, os discos foram distribuídos aleatoriamente, em área próxima ao plantio, no espaçamento de 0,5m, permanecendo durante 18 meses, período no qual foram efetuadas seis inspeções trimestrais para avaliar o grau de deterioração e coleta de insetos. Para o ensaio em condição urbana, os discos foram secionados axialmente para a retirada da medula e distribuídos aleatoriamente, nas posições côncava e convexa, sobre uma estrutura de madeira, localizada no Campus do INPA em Manaus, e inspecionados bimestralmente por um ano. Os resultados do ensaio no ambiente florestal indicaram que a maioria dos discos foi deteriorada por térmitas e a vida útil da base foi em torno de 18 meses, a do meio e do topo em torno de 15. As principais espécies de cupins foram: Heterotermes tenuis (Hagen (Rhinotermitidae responsável pela deterioração da parte basal, mediana e o topo; Nasutitermes similis Emerson (Termitidae que infestou a região da base e do meio; Anoplotermes sp.(Termitidae e Nasutitermes tatarandae (Holmgren (Termitidae responsáveis pela infestação da parte mediana do estipe. No ambiente urbano, o principal responsável pela deterioração das amostras foi o besouro Dinoderus bifoveolatus Wollston (Bostrichidae, e em seguida, o térmita N. similis.The durability of the stipe of Bactris gasipaes Kunth (Peach palm when under attack by xylophage insects, is evaluated in

Abundance, biomass and caloric content of Chukchi Sea bivalves and association with Pacific walrus (Odobenus rosmarus divergens) relative density and distribution in the northeastern Chukchi Sea

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Young, Jordann K.; Black, Bryan A.; Clarke, Janet T.; Schonberg, Susan V.; Dunton, Kenneth H.

2017-10-01

The northeastern Chukchi Sea is a shallow subarctic shelf ecosystem that supports a substantial benthic infaunal community of which bivalves are a major component. We assessed the patterns in population abundance, biomass, and caloric content of ten dominant bivalve taxa in relation to the distribution of the upper trophic level consumer Pacific walrus (Odobenus rosmarus divergens). Bivalves were collected over four cruises in the northeastern Chukchi Sea (2009, 2010, 2012, 2013). Our samples were largely dominated by calorie-dense, deposit-feeding species, including Macoma spp., Ennucula tenuis, Nuculana spp. and Yoldia spp. Weight-frequency distributions were strongly right-skewed for most taxa, though some showed evidence of a bimodal distribution. Caloric densities as measured through bomb calorimetry significantly differed among taxa (ANOVA F = 32.57, df = 9, p-valueanimal wet weight was found to be a reliable predictor of whole animal caloric content. Bivalve populations and peak caloric densities were centered on and to the southeast of Hanna Shoal, which coincided with peak Pacific walrus relative density (walruses per km surveyed) from July through October. Significant differences in mean caloric values were found between areas with and without walruses present (student's t-test, t=-2.9088, df = 252.24, p-value = 0.003952), as well as between areas with low and high walrus relative densities in the pooled annual dataset and in each individual month except October (ANOVA, p-value<0.05). The high-calorie deposit feeders that dominate these bivalve communities preferentially consume food sources, such as sea ice algae, that are likely to be affected by shifting sea ice dynamics. As such, continued warming has the potential to alter bivalve communities in the northeastern Chukchi Sea, which may have profound implications for upper trophic levels.

Systematics of Trichoteleia Kieffer and Paridris Kieffer (Hymenoptera, Platygastroidea, Platygastridae

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Elijah Talamas

2013-08-01

Full Text Available Paridris Kieffer and Trichoteleia Kieffer are morphologically similar genera of solitary egg parasitoids with little overlap between their distributions: Paridris is found commonly worldwide with the exceptions of Madagascar, from which a single specimen is known, and New Zealand, from which no records are known; Trichoteleia is endemic to the Malagasy islands. Here we present the first phylogenetic analysis of platygastroid wasps that combines and compares morphological and molecular data. We find the results of the phylogenetic analyses of the two data sources to be largely congruent for the species treated here. Paridris and Trichoteleia are found to be monophyletic, as are two morphologically well-defined species groups within Paridris. Neoparidris Galloway is found to belong within Paridris and is treated as a junior synonym, syn. n. The faunas of Paridris from Africa, Melanesia and the Indo-Malay islands are revised. Fifteen species are described of which 9 are new: Paridris anikulapo Talamas, sp. n. (sub-Saharan Africa; Paridris densiclava (Kieffer, (Seychelles; Paridris bispinosa (Masner, (Gabon; Paridris nigriclava (Kieffer, (Seychelles; Paridris nitidiceps (Kieffer, (Seychelles; Paridris tenuis (Nixon, (sub-Saharan Africa; Paridris trispinosa Talamas & Masner, sp. n., (Cameroon, Democratic Republic of the Congo; Paridris bifurcata (Dodd, comb. n., (Australia, Papua New Guinea; Paridris mnestros Talamas & Masner, sp. n., (Indonesia, Malaysia; Paridris pantex Talamas, sp. n., (Fiji; Paridris phrikos Talamas & Masner, sp. n., (Fiji; Paridris skolops Talamas & Masner, sp. n., (Fiji; Paridris sulcata Talamas, sp. n., (Vanuatu; Paridris taekuli Talamas & Masner, sp. n., (Australia, Bangladesh, Fiji, India, Indonesia, Ivory Coast, Madagascar, New Caledonia, Thailand, Vietnam; Paridris xestos Talamas & Masner, sp. n., (Fiji. Paridris flaviclava (Kieffer, syn. n., and P. nigraticeps (Kieffer, syn. n., are treated as junior synonyms of P

Seasonal and interannual variations in coccolithophore abundance off Terceira Island, Azores (Central North Atlantic)

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Narciso, Áurea; Gallo, Francesca; Valente, André; Cachão, Mário; Cros, Lluïsa; Azevedo, Eduardo B.; e Ramos, Joana Barcelos

2016-04-01

In order to characterize the natural coccolithophore community occurring offshore Azores and to determine their annual and interannual patterns, monthly samples were collected, from September 2010 to December 2014, in the photic zone off Terceira Island. The present study revealed a clear seasonal distribution and a considerable interannual variability of the living coccolithophore community. The highest coccolithophore abundances were observed during spring and winter months, especially due to the smaller species Emiliania huxleyi and Gephyrocapsa ericsonii. In fact, the highest biomass period was registered during April 2011, associated with enhanced abundance of the overcalcified morphotype of E. huxleyi, which was possibly influenced by subpolar waters and subsequent upwelling conditions. The highest abundances of Gephyrocapsa muellerae were recorded during June 2011 and 2014, indicating that this species characterizes the transition between the period of maximum productivity and the subsequent smoother environmental conditions, the first and the later stages of the phytoplankton succession described by Margalef, respectively. During summer to early fall, a gradual decrease of the overall coccolithophore abundance was observed, while the species richness (Margalef diversity index) increased. A subtropical coccolithophore assemblage mainly composed by Umbellosphaera tenuis, Syracosphaera spp., Discosphaera tubifera, Rhabdosphaera clavigera and Coronosphaera mediterranea indicated the presence of surface warmer waters accompanied by reduced mixing and low nutrients concentration. During late fall to winter, the coccolithophore abundance increased again with a concomitant reduction in species diversity. This is potentially linked to low sea surface temperatures, moderate nutrients concentration and surface mixed layer deepening. During 2011, colder and productive waters led to an increase in the total coccolithophore abundances. On contrary, during 2012

Systematics of the family Plectopylidae in Vietnam with additional information on Chinese taxa (Gastropoda, Pulmonata, Stylommatophora

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Barna Páll-Gergely

2015-01-01

Full Text Available Vietnamese species from the family Plectopylidae are revised based on the type specimens of all known taxa, more than 600 historical non-type museum lots, and almost 200 newly-collected samples. Altogether more than 7000 specimens were investigated. The revision has revealed that species diversity of the Vietnamese Plectopylidae was previously overestimated. Overall, thirteen species names (anterides Gude, 1909, bavayi Gude, 1901, congesta Gude, 1898, fallax Gude, 1909, gouldingi Gude, 1909, hirsuta Möllendorff, 1901, jovia Mabille, 1887, moellendorffi Gude, 1901, persimilis Gude, 1901, pilsbryana Gude, 1901, soror Gude, 1908, tenuis Gude, 1901, verecunda Gude, 1909 were synonymised with other species. In addition to these, Gudeodiscus hemmeni sp. n. and G. messageri raheemi ssp. n. are described from north-western Vietnam. Sixteen species and two subspecies are recognized from Vietnam. The reproductive anatomy of eight taxa is described. Based on anatomical information, Halongella gen. n. is erected to include Plectopylis schlumbergeri and P. fruhstorferi. Additionally, the genus Gudeodiscus is subdivided into two subgenera (Gudeodiscus and Veludiscus subgen. n. on the basis of the morphology of the reproductive anatomy and the radula. The Chinese G. phlyarius werneri Páll-Gergely, 2013 is moved to synonymy of G. phlyarius. A spermatophore was found in the organ situated next to the gametolytic sac in one specimen. This suggests that this organ in the Plectopylidae is a diverticulum. Statistically significant evidence is presented for the presence of calcareous hook-like granules inside the penis being associated with the absence of embryos in the uterus in four genera. This suggests that these probably play a role in mating periods before disappearing when embryos develop. Sicradiscus mansuyi is reported from China for the first time.

Ictiofauna de sistemas cárstico-palustres con impacto antrópico: los petenes de Campeche, México

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Ivette Liliana Torres-Castro

2009-06-01

Full Text Available Los petenes son pequeños manantiales y arroyos asociados que drenan a sistemas palustres en áreas cársticas costeras. Se estudió la composición, distribución y abundancia de la ictiofauna en dos petenes del noroeste de Campeche, en el manantial principal, el arroyo asociado, y pequeños ojos de agua secundarios (temporales, en dos épocas del año. Se registraron variables ambientales y tipos de impacto antrópico en cada petén. Se encontraron en total 27 especies de peces, con extensiones de ámbito de ‘Cichlasoma’ salvini, Rivulus tenuis, Phallichthys fairweatheri, Xiphophorus hellerii y X. maculatus. La especie dominante en ambas épocas fue Astyanax (probables híbridos A. aeneus × altior en Hampolol, A. altior en El Remate. Hubo diferencia significativa en diversidad entre ambos petenes. El análisis de conglomerados diferenció dos agrupaciones dentro de cada petén: aguas permanentes y sitios temporales. Las variables ambientales (excepto salinidad presentaron diferencias significativas por sitio y época; un análisis de correspondencia canónica indicó que la distribución de los conjuntos de peces tuvo influencia de las variables ambientales en ambas temporadas. En términos de composición, los factores históricos juegan un papel en las diferencias ictiológicas entre ambos petenes, sobre todo por lo que concierne a la presencia de híbridos de Astyanax, así como Xiphophorus hellerii en el petén del sur (Hampolol y de Poecilia velifera en el petén del norte (El Remate.Ichthyofauna of karstic wetlands under anthropic impact: the "petenes" of Campeche, Mexico. "Petenes" are small springs and associated streams that drain into wetlands near the coast in karstic areas. We studied composition, distribution, and abundance of the ichthyofauna in Los Petenes region (northwest Campeche. Two petenes displaying different degrees and types of anthropic impact were selected, Hampolol and El Remate. Hampolol has a smaller area but

Anthropogenic infilling of a Bermudian sinkhole and its impact on sedimentation and benthic foraminifera in the adjacent anchialine cave environment

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Jacquelyn N. Cresswell

2017-09-01

Full Text Available In the mid-20th century, an inland brackish pond from Bermuda, known as Eve’s Pond, was filled with marine sediment from an adjacent coastal lagoon. At this time, an eyewitness reported “…sediment billowing out of the Green Bay Cave for days…”, which is a marine-dominated anchialine cave located proximal to the former location of Eve’s Pond (~200 m. The purpose of this study was to evaluate the potential impact of this infilling event on cave sedimentation and benthic meiofaunal communities, as proxied by the unicellular protists foraminifera that remain preserved in the sediment record. Eight sediment cores were collected from an underwater passage in Green Bay Cave in a transect towards the location where Eve’s Pond was surveyed in 1901 CE. The sediment cores were analyzed for visual and density changes (photography, X-radiography, textural variability, benthic foraminifera fauna and diversity, and radiocarbon dating. The recovered sediment cores mostly sampled a late Holocene carbonate mud facies that had been described during previous research in the cave, with benthic foraminiferal assemblages post-dating the onset of seawater circulating between the saline groundwater flooding the cave and the adjacent Harrington Sound ~1,900 years ago. However, two cores located further into the cave (cores 13 and 17 contain a carbonate sand layer with lagoon foraminifera that is anomalous with respect to the Holocene depositional history of the cave and is most likely related to the mid-20th century infilling of Eve’s Pond. Examination of these two cores showed that after the infilling event, the community of benthic foraminifera rapidly reverted to pre-impact assemblages with foraminiferal stygophiles (e.g., Spirophthalmidium emaciatum, Sigmoilina tenuis, which were not displaced by new colonizers introduced into the cave by the dredge spoils. We caution that the results cannot be extrapolated to the pelagic crustacean community, but the

Trophodynamics of the Hanna Shoal Ecosystem (Chukchi Sea, Alaska): Connecting multiple end-members to a rich food web

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McTigue, N. D.; Dunton, K. H.

2017-10-01

Predicting how alterations in sea ice-mediated primary production will impact Arctic food webs remains a challenge in forecasting ecological responses to climate change. One top-down approach to this challenge is to elucidate trophic roles of consumers as either specialists (i.e., consumers of predominantly one food resource) or generalists (i.e., consumers of multiple food resources) to categorize the dependence of consumers on each primary producer. At Hanna Shoal in the Chukchi Sea, Alaska, we used stable carbon and nitrogen isotope data to quantify trophic redundancy with standard ellipse areas at both the species and trophic guild levels. We also investigated species-level trophic plasticity by analyzing the varying extents that three end-members were assimilated by the food web using the mixing model simmr (Stable Isotope Mixing Model in R). Our results showed that ice algae, a combined phytoplankton and sediment organic matter composite (PSOM), and a hypothesized microphytobenthos (MPB) component were incorporated by consumers in the benthic food web, but their importance varied by species. Some primary consumers relied heavily on PSOM (e.g, the amphipods Ampelisca sp. and Byblis sp.; the copepod Calanus sp.), while others exhibited generalist feeding and obtained nutrition from multiple sources (e.g., the holothuroidean Ocnus glacialis, the gastropod Tachyrhynchus sp., the sipunculid Golfingia margaritacea, and the bivalves Ennucula tenuis, Nuculana pernula, Macoma sp., and Yoldia hyperborea). Most higher trophic level benthic predators, including the gastropods Buccinum sp., Cryptonatica affinis, and Neptunea sp, the seastar Leptasterias groenlandica, and the amphipod Anonyx sp. also exhibited trophic plasticity by coupling energy pathways from multiple primary producers including PSOM, ice algae, and MPB. Our stable isotope data indicate that consumers in the Hanna Shoal food web exhibit considerable trophic redundancy, while few species were specialists

Multiscale patterns in the diversity and organization of benthic intertidal fauna among French Atlantic estuaries

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Blanchet, Hugues; Gouillieux, Benoît; Alizier, Sandrine; Amouroux, Jean-Michel; Bachelet, Guy; Barillé, Anne-Laure; Dauvin, Jean-Claude; de Montaudouin, Xavier; Derolez, Valérie; Desroy, Nicolas; Grall, Jacques; Grémare, Antoine; Hacquebart, Pascal; Jourde, Jérôme; Labrune, Céline; Lavesque, Nicolas; Meirland, Alain; Nebout, Thiebaut; Olivier, Frédéric; Pelaprat, Corine; Ruellet, Thierry; Sauriau, Pierre-Guy; Thorin, Sébastien

2014-07-01

Based on a parallel sampling conducted during autumn 2008, a comparative study of the intertidal benthic macrofauna among 10 estuarine systems located along the Channel and Atlantic coasts of France was performed in order to assess the level of fauna similarity among these sites and to identify possible environmental factors involved in the observed pattern at both large (among sites) and smaller (benthic assemblages) scales. More precisely this study focused on unraveling the observed pattern of intertidal benthic fauna composition and diversity observed at among-site scale by exploring both biotic and abiotic factors acting at the among- and within-site scales. Results showed a limited level of similarity at the among-site level in terms of intertidal benthic fauna composition and diversity. The observed pattern did not fit with existing transitional water classification methods based on fish or benthic assemblages developed in the frame of the European Water Framework Directive (WFD). More particularly, the coastal plain estuaries displayed higher among-site similarity compared to ria systems. These coastal plain estuaries were characterized by higher influence of river discharge, lower communication with the ocean and high suspended particulate matter levels. On the other hand, the ria-type systems were more dissimilar and different from the coastal plain estuaries. The level of similarity among estuaries was mainly linked to the relative extent of the intertidal "Scrobicularia plana-Cerastoderma edule" and "Tellina tenuis" or "Venus" communities as a possible consequence of salinity regime, suspended matter concentrations and fine particles supply with consequences on the trophic functioning, structure and organization of benthic fauna. Despite biogeographical patterns, the results also suggest that, in the context of the WFD, these estuaries should only be compared on the basis of the most common intertidal habitat occurring throughout all estuarine systems

The Features of Naturalization of Invasive Fraction of Flora in the Voronezh Region and in Some Regions of the European Part of Russia

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Vladimirov D.R.

2015-10-01

Full Text Available The article is about naturalization features of invasive fraction of flora in Voronezh and some other regions of the European part of Russia. The summary table represents all invasive and potentially invasive plants of the European part of Russia with their level of naturalization (or invasive status. Invasive fraction of flora in the Voronezh region numbers 120 plants. All of them are on different stages of naturalization process in an anthropogenic areal. Invasive plants represent by agriophyts – 41 (34,1 % species, epecophyts – 75 (62,5 % species and colonophyts-epecophyts – 4 (3,4 % species. Totally there are 201 species of invasive and potentially invasive plants spread within European part of Russia (Northern-West Russia, Ivanovo, Kaluga, Tver, and Voronezh regions. They formed the “black list” of European Russia. 10 species are common to all invasive fractions. These are Acer negundo, Amelanchier x spicata, Aster x salignus, Echinocystis lobata, Elodea canadensis, Heracleum sosnowskyi, Impatiens glandulifera, Impatiens parviflora, Juncus tenuis and Lupinus polyphyllus. The analysis of the general list of invasive fractions of European Russia shows that 120 species of the list are invasive or potentially invasive in the Voronezh region (100 and 20 species in accordance, adventives naturalized species – 31, native species – 19, archaeophyts – 2, apophyts – 4. 26 species from the list were not found in the Voronezh region. Apparently, the region is a transit area for many invasive plants, which migrate from South to North, from East to West etc. Not only its natural and climatic potential, but also high level of transformation of local landscapes enabled immigrant-plants to naturalize within the bounds of the region. Furthermore, for many years the Voronezh region was the center of introduction of alien plants. Many of those became a part of invasion fraction of regional flora. In recent decades green building took place of

Abiotic factors affect the recruitment and biomass of perennial grass and evergreen shrub seedlings in denuded areas of Patagonian Monte rangelands.

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Bosco, Tomás; Bertiller, Mónica Beatriz; Carrera, Analía Lorena

2018-07-15

Assessing the ability of key species to cope with environmental stresses in disturbed areas is an important issue for recovery of degraded arid ecosystem. Our objective was to evaluate the effect of soil moisture, exposure to UV radiation, and presence/absence of litter with different chemistry on soil N, recruitment and biomass of seedlings of perennial grass (Poa ligularis and Nassella tenuis) and evergreen shrub species (Atriplex lampa and Larrea divaricata) in denuded areas. We carried out a microcosm experiment with soil blocks (28 cm depth) sowed with seeds of the target species, subjected to different levels of litter type (perennial grass-evergreen shrub mixture, evergreen shrub mixture, and no litter), UV radiation (near ambient and reduced UV), and soil water (high: 15-25% and low 5-15%). Periodically, during 6 months, we assessed soil-N (total and inorganic) at two depths and species seedling recruitment at microcosms. Additionally, emerged seedlings of each species were transplanted to individual pots containing soil and subjected to the same previous factors during 12 months. Then, all plants were harvested and biomass assessed. Only inorganic soil-N at the upper soil varied among treatments increasing with the presence of evergreen shrub litter, exposure to ambient UV, and high soil water. Inorganic soil-N, promoted by near ambient UV and high soil water, had a positive effect on recruitment of perennial grasses and A. lampa. Both litter types promoted the recruitment of perennial grasses. Evergreen shrub litter and high soil water promoted the recruitment of L. divaricata. Seedling biomass of perennial grasses increased with high soil water and reduced UV. Ambient UV had positive or null effects on biomass of evergreen shrub seedlings. High soil water increased biomass of L. divaricata seedlings. We concluded that soil water appeared as the most limiting factor for seedling recruitment of all species whereas inorganic soil N limited the

Soil acidification and liming in grassland production and grassland soil fertility in Slovenia

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Jure ČOP

2015-12-01

Full Text Available This paper reviews the evidences on grassland soil acidity and liming in relation to soil processes and herbage production. There is also an outline of the present state of soil acidity and acidity-related traits – contents of organic matter (OM, phosphorus (P and potassium (K in Slovene grassland. In grassland, soil acidification is an ongoing process under humid climate conditions. It is mainly driven by leaching of nutrients, net loss of cations due to retention in livestock products, use of physiologically acid fertilizers, acid rain and N2 fixation. This process is reduced by strong pH buffering capacity of the soil and by physiologically basic fertilizers. Acid grassland soils in Slovenia are widely distributed in spite of the fact that 44% of the total land has developed from a carbonate parent material. Of the 1713 grassland soil samples analysed during 2005-2007 45% were regarded as acid ones (pH < 5.5; in KCl, 57% as soils with very low P status (˂ 6 mg P2O5/100 g soil and 22% as soils with very low K status (˂ 10 mg K2O/100 soil. Increased content of soil organic matter was identified for alpine pastures (˃ 10 % OM in 44% of samples, mainly as a result of low decomposition rate. Liming of acid grassland soils did not always reflect in a higher herbage yield. The cause for this inefficiency is plant composition of grassland. Thus, many grassland plants with relatively high production potential have adapted to acid soil conditions. To illustrate the inconsistent liming effect three researches are reviewed. In the first two researches liming along with fertilizer application did not increase the yield comparing to the fertilized control while in the third research the increase amounted 26 %. Liming improves considerably botanical composition of the acid grassland (e.g. sward where Common Bent – Agrostis tenuis Sibth. – prevails and thus indirectly affects palatability and nutritive value of herbage. Grassland liming has a weak

Progress towards the experimental reintroduction of woodland caribou to Minnesota and adjacent Ontario

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Peter A. Jordan

1998-03-01

Full Text Available Woodland caribou (Rangifer tarandus caribou are native to Minnesota but started to decline in the mid 1800s and disappeared from the state by 1940. Their demise had been attributed to extensive timber harvest and ovethunting; but more recently mortality from the meningeal worm, Parelaphostrongylus tenuis, carried by white-tailed deer (Odocoileus virginianus, and increased prédation by timber wolves (Canis lupus and black bears (Ursus americanus have been suggested as additional causes. We describe a current initiative to explore feasibility of restoring caribou to the boundary waters region of Minnesota and Ontario. Feasibility studies have been conducted under the guidance of the North Central Catibou Corporation (NCCC, a non-governmental organization with representation from relevant state, federal, Native American, and Canadian agencies. Results indicate a Within Minnesota the most suitable site for woodland caribou lies within the eastern sector of the Boundary Waters Canoe Area Wilderness (BWCAW, and this is contiguous with a similarly suitable sector of Ontario's Quetico Provincial Park: Together these comprise the recommended 1300-km2 Boundary Waters Caribou Region (BWCR; b Vegetation in the BWCR has changed little since the 1920s when caribou were last present other than effects of fire suppression; c Level of white-tailed deer, hence the meningeal worm, is so low in the BWCR that this factor is unlikely to impede survival of re-introduced caribou; d While wolf numbers within the wider region are relatively high, their impacts may be minimized if caribou are released in small, widely scattered groups; in addition, an abundance of lakes with islands affords good summer-time prédation security; e Threat to calves from black bears, probably more numerous than in earlier times, appears lessened by the security of lakeshores and islands; and f A simulation model, combining knowledge from elsewhere with the BWCR assessment, suggests that

Host cell and expression engineering for development of an E. coli ketoreductase catalyst: Enhancement of formate dehydrogenase activity for regeneration of NADH

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Mädje Katharina

2012-01-01

Full Text Available Abstract Background Enzymatic NADH or NADPH-dependent reduction is a widely applied approach for the synthesis of optically active organic compounds. The overall biocatalytic conversion usually involves in situ regeneration of the expensive NAD(PH. Oxidation of formate to carbon dioxide, catalyzed by formate dehydrogenase (EC 1.2.1.2; FDH, presents an almost ideal process solution for coenzyme regeneration that has been well established for NADH. Because isolated FDH is relatively unstable under a range of process conditions, whole cells often constitute the preferred form of the biocatalyst, combining the advantage of enzyme protection in the cellular environment with ease of enzyme production. However, the most prominent FDH used in biotransformations, the enzyme from the yeast Candida boidinii, is usually expressed in limiting amounts of activity in the prime host for whole cell biocatalysis, Escherichia coli. We therefore performed expression engineering with the aim of enhancing FDH activity in an E. coli ketoreductase catalyst. The benefit resulting from improved NADH regeneration capacity is demonstrated in two transformations of technological relevance: xylose conversion into xylitol, and synthesis of (S-1-(2-chlorophenylethanol from o-chloroacetophenone. Results As compared to individual expression of C. boidinii FDH in E. coli BL21 (DE3 that gave an intracellular enzyme activity of 400 units/gCDW, co-expression of the FDH with the ketoreductase (Candida tenuis xylose reductase; XR resulted in a substantial decline in FDH activity. The remaining FDH activity of only 85 U/gCDW was strongly limiting the overall catalytic activity of the whole cell system. Combined effects from increase in FDH gene copy number, supply of rare tRNAs in a Rosetta strain of E. coli, dampened expression of the ketoreductase, and induction at low temperature (18°C brought up the FDH activity threefold to a level of 250 U/gCDW while reducing the XR activity by

Art in Paleontology: The Example of Manfred Reichel

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Leria, M.; Ferràndez-Cañadell, C.

2013-12-01

this ability to elaborate vivid restorations of pterosaurus and extinct birds, such as Archaeopteryx. This study is based on a revision of the scientific papers by Manfred Reichel, along with some of the work done by his students related to the foraminiferal research. In addition, the examination of the collection of Reichel's drawings and casts held by the Natural History Museum in Basel, as well as interviews with his family and students were highly helpful to understand how he applied his artistic skills to teaching and research. From this study, we can assess the significance of visual education on micropaleontologists, arguing that classical convention in drawing is still and irreplaceable tool in natural sciences. Illustration of the test, scale 1:50, of Praealveolina cretacea tenuis. (Manfred Reichel, 1937. Étude sur les Alvéolines, Mémoires de la Société paléontologique Suisse, Vol. LIX, plate XI, fig. IIa)

Pathogens, nutritional deficiency, and climate influences on a declining moose population

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Murray, D.L.; Cox, E.W.; Ballard, W.B.; Whitlaw, Heather A.; Lenarz, M.S.; Custer, T.W.; Barnett, T.; Fuller, T.K.

2006-01-01

Several potential proximate causes may be implicated in a recent (post-1984) decline in moose (Alces alces andersoni) numbers at their southern range periphery in northwest Minnesota, USA. These causes include deleterious effects of infectious pathogens, some of which are associated with white-tailed deer (Odocoileus virginianus), negative effects of climate change, increased food competition with deer or moose, legal or illegal hunting, and increased predation by gray wolves (Canis lupus) and black bears (Ursus americanus). Long-standing factors that may have contributed to the moose decline include those typically associated with marginal habitat such as nutritional deficiencies. We examined survival and productivity among radiocollared (n = 152) adult female and juvenile moose in northwest Minnesota during 1995–2000, and assessed cause of death and pathology through carcass necropsy of radiocollared and non-radiocollared animals.Aerial moose surveys suggested that hunting was an unlikely source of the numerical decline because the level of harvest was relatively low (i.e., approx. 15% / 2 yr) and the population usually grew in years following a hunt. The majority of moose mortalities (up to 87% of radiocollared moose [n = 76] and up to 65% of non-radiocollared moose [n = 84]) were proximally related to pathology associated with parasites and infectious disease. Liver fluke (Fascioloides magna) infections apparently constituted the greatest single source of mortality and caused significant pathology in the liver, thoracic and peritoneal cavities, pericardial sac, and lungs. Mortality due to meningeal worm (Parelaphostrongylus tenuis) was less prevalent and was manifested through characteristic neurological disease. Several mortalities apparently were associated with unidentified infectious disease, probably acting in close association with malnutrition. Bone-marrow fat was lower for moose dying of natural causes than those dying of anthropogenic factors or

A systematic revision of Operclipygus Marseul (Coleoptera, Histeridae, Exosternini

Directory of Open Access Journals (Sweden)

Michael Caterino

2013-02-01

. panamensis (Wenzel & Dybas, 1941], O. sejunctus group [O. depressus (Hinton, 1935, O. itoupe sp. n., O. juninensis sp. n., O. pecki sp. n., O. punctiventer sp. n., O. sejunctus (Schmidt, 1896 comb. n., O. setiventris sp. n.], O. mortavis group [O. ecitonis sp. n., O. mortavis sp. n., O. paraguensis sp. n.], O. dytiscoides group [O. carinisternus sp. n., O. crenulatus sp. n., O. dytiscoides sp. n., O. quadratus sp. n.], O. dubitabilis group [O. dubitabilis (Marseul, 1889, O. yasuni sp. n.], O. angulifer group [O. angulifer sp. n., O. impressifrons sp. n.], O. dubius group [O. andinus sp. n., O. dubius (Lewis, 1888, O. extraneus sp. n., O. intermissus sp. n., O. lunulus sp. n., O. occultus sp. n., O. perplexus sp. n., O. remotus sp. n., O. validus sp. n., O. variabilis sp. n.], O. hospes group [O. assimilis sp. n., O. belemensis sp. n., O. bulbistoma sp. n., O. callifrons sp. n., O. colombicus sp. n., O. communis sp. n., O. confertus sp. n., O. confluens sp. n., O. curtistrius sp. n., O. diffluens sp. n., O. fusistrius sp. n., O. gratus sp. n., O. hospes (Lewis, 1902, O. ibiscus sp. n., O. ignifer sp. n., O. impositus sp. n., O. incisus sp. n., O. innocuus sp. n., O. inquilinus sp. n., O. minutus sp. n., O. novateutoniae sp. n., O. praecinctus sp. n., O. prominens sp. n., O. rileyi sp. n., O. subterraneus sp. n., O. tenuis sp. n., O. tiputinus sp. n.], O. farctus group [O. atlanticus sp. n., O. bidessois (Marseul, 1889, O. distinctus (Hinton, 1935, O. distractus (Schmidt, 1896 comb. n., O. farctissimus sp. n., O. farctus (Marseul, 1864, O. gilli sp. n., O. impressistrius sp. n., O. inflatus sp. n., O. latemarginatus (Bickhardt, 1920 comb. n., O. petrovi sp. n., O. plicatus (Hinton, 1935 comb. n., O. prolixus sp. n., O. punctifrons sp. n., O. proximus sp. n., O. subrufus sp. n.], O. hirsutipes group [O. guianensis sp. n., O. hirsutipes sp. n.], O. hamistrius group [O. arquus sp. n., O. campbelli sp. n., O. chiapensis sp. n., O. dybasi sp. n., O. geometricus (Casey, 1893 comb. n