Parasites of ornamental fish imported into Australia

Five commonly imported freshwater ornamental fish: Poecilia reticulata (guppy); Xiphophorus maculatus (platy); Paracheirodon innesi (neon tetra); Paracheirodon axelrodi (cardinal tetra); and Gyrinocheilus aymonieri (sucking catfish), 361 individuals in total, were examined for parasites immediately after being released from quarantine in Australia. Ten parasites species were found: Camallanus cotti; Centrocestus formosanus; Bothriocephalus acheilognathi; Urocleidoides reticulatus; Tetrahymena corlissi; Chilodonella piscicola; Hexamita sp.; Cryptobia sp.; Chloromyxum sp.; and an unidentified larval nematode. Though shipments had come from up to five different exporting companies, parasite prevalence was uniformly high. We suggest that prior to release, fish transported internationally should be checked for high risk pathogens such as Camallanus cotti, B. acheilognathi and Centrocestus formosanus, and treated for common infections such as Hexamita sp., Cryptobia sp. T. corlissi and Chilodonella piscicola to inhibit the spread of disease and enhance the survival of the fish.

On the maintenance of sex-chromosome polymorphism by sex-antagonistic selection

Complex sex-determination systems are a priori unstable and require specific selective forces for their maintenance. Analytical derivations have suggested that sex-antagonistic selection may play such a role, but this assumed absence of recombination between the sex-determining and sex-antagonistic genes. Using individual-based simulations, and focusing on the sex chromosome and coloration polymorphisms of platy fishes as a case study, we show that the conditions for polymorphism maintenance induce female-biases in primary sex ratios, so that sex-ratio selection makes the system collapse towards male- or female heterogamety as soon as recombinant genotypes appear. However, a polymorphism can still be maintained under scenarios comprising strong sexual selection against dull males, mild natural selection against bright females, and low recombination rates. Though such conditions are plausibly met in natural populations of fishes harbouring such polymorphisms, quantitative empirical evaluations are required to properly test whether sex-antagonistic selection is a causal agent, or if other selective processes are required (such as local mate competition favouring female biased sex ratios).

The oceanic base of slope record of the Permian-Triassic crisis: view from Tethys (Oman)

The Oman Mountains provide some of the best sections of Permian and Triassic sediments from ocean sea floor to base-of-slope environments related to the distal South Tethyan margin. The central part of the range exposes the Buday'ah section of oceanic sediments in the so-called "Hawasina allochtons". The locality of Wadi Maqam in the north-western part of the Oman Mountains is among places where the thick Permian-Triassic base-of-slope sediments is exposed (Baud et al., 2001). Overlying 400 m of middle Permian limestones and dolomites, the upper Permian sediments consist of 50 m of ≈ 10 cm thick beds of cherts and dolomites rich in sponge spicules. The top of the Permian units is well bioturbated lime mudstone-wackestone, devoid of cherts and dated as late Changhsingian (Krystyn in Richoz et al., 2005). The boundary yellow shales are overlain by very thinly bedded, laminated microbial platy lime mudstone with H. parvus. The dramatic loss of the burrowing infauna indicates the appearance of oxygen-poor water. These Induan sediments are about 25 m thick and show at the top the first calcirudites, commonly clast-supported (edge-wise conglomerates), and are characterized by tabular clasts representing the sub- in situ reworking of the laminated, platy calcilutite. The very thick Smithian overlying litho-unit (up to 900 m) marks the onset on the base-of-slope of a deep-marine basin in which carbonate submarine fan deposits developed This very thick unit consists essentially of platy limestones, calcarenites and calcirudites. It comprises mainly grey-beige calcilutite, laminated and flaggy, interbedded with sparse beds of fine-grained calcarenite in cm beds. Channelized beds of intraformational calcirudite are also part of this succession which constitutes the greater part of the outcrop available. During the Spathian to Anisian, the sedimentation changes to terrigenous mudstone and siltstone that ended with Ladinian radiolarites.

Sur la présence de Meandrospira pusilla (Ho) (Foraminifère) dans le Trias inférieur de Kuh e Ali Bashi, Julfa NW Iran.

In the course of preliminary micropaleontologic and sédilmentologic investigations of several sections in the Lower Trias of Julfa, NW Iran, the stratigraphically significant meandrospira pusilla (Ho) (= Citaella iulia PREMOLI SILVA) was shown to be present in the uppermost beds of the platy limestones of the Elika formation

Spray coating technique asa surface treatment for woodcontaining paper grades

The objective of this work was to introduce the emerging non-contacting spray coating process and compare it to the existing coating techniques. Particular emphasis was given to the details of the spraying process of paper coating colour and the base paper requirements set by the new coating method. Spraying technology itself is nothing new, but the atomisation process of paper coating colour is quite unknown to the paper industry. The differences between the rheology of painting and coating colours make it very difficult to utilise the existing information from spray painting research. Based on the trials, some basic conclusion can be made:The results of this study suggest that the Brookfield viscosity of spray coating colour should be as low as possible, presently a 50 mPas level is regarded as an optimum. For the paper quality and coater runnability, the solids level should be as high as possible. However, the graininess of coated paper surface and the nozzle wear limits the maximum solids level to 60 % at the moment. Most likelydue to the low solids and low viscosity of the coating colour the low shear Brookfield viscosity correlates very well with the paper and spray fan qualities. High shear viscosity is also important, but yet less significant than the low shear viscosity. Droplet size should be minimized and besides keeping the brrokfield viscosity low that can be helped by using a surfactant or dispersing agent in the coating colour formula. Increasing the spraying pressure in the nozzle can also reduce the droplet size. The small droplet size also improves the coating coverage, since there is hardly any levelling taking place after the impact with the base paper. Because of the lack of shear forces after the application, the pigment particles do not orientate along the paper surface. Therefore the study indicates that based on the present know-how, no quality improvements can be obtained by the use of platy type of pigments. The other disadvantage of them is the rapid deterioration of the nozzle lifetime. Further research in both coating colour rheology and nozzle design may change this in the future, but so far only round shape pigments, like typically calcium carbonate is, can be used with spray coating. The low water retention characteristics of spray coating, enhanced by the low solids and low viscosity, challenge the base paper absorption properties.Filler level has to be low not to increase the number of small pores, which have a great influence on the absorption properties of the base paper. Hydrophobic sizing reduces this absorption and prevents binder migration efficiently. High surface roughness and especially poor formation of the base paper deteriorate thespray coated paper properties. However, pre-calendering of the base paper does not contribute anything to the finished paper quality, at least at the coating colour solids level below 60 %. When targeting a standard offset LWC grade, spraycoating produces similar quality to film coating, but yet blade coating being on a slightly better level. However, because of the savings in both investment and production costs, spray coating may have an excellent future ahead. The porousnature of the spray coated surface offers an optimum substrate for the coldset printing industry to utilise the potential of high quality papers in their business.

Determination of compression behaviour of coating layer

The strength properties of paper coating layer are very important in converting and printing operations. Too great or low strength of the coating can affect several problems in printing. One of the problems caused by the strength of coating is the cracking at the fold. After printing the paper is folded to final form and the pages are stapled together. In folding the paper coating can crack causing aesthetic damage over printed image or in the worst case the centre sheet can fall off in stapling. When folding the paper other side undergoes tensile stresses and the other side compressive stresses. If the difference between these stresses is too high, the coating can crack on the folding. To better predict and prevent cracking at the fold it is good to know the strength properties of coating layer. It has measured earlier the tensile strength of coating layer but not the compressive strength. In this study it was tried to find some way to measure the compressive strength of the coating layer and investigate how different coatings behave in compression. It was used the short span crush test, which is used to measure the in-plane compressive strength of paperboards, to measure the compressive strength of the coating layer. In this method the free span of the specimen is very small which prevent buckling. It was measured the compressive strength of free coating films as well as coated paper. It was also measured the tensile strength and the Bendtsen air permeance of the coating film. The results showed that the shape of pigment has a great effect to the strength of coating. Platy pigment gave much better strength than round or needle-like pigment. On the other hand calcined kaolin, which is also platy but the particles are aggregated, decreased the strength substantially. The difference in the strength can be explained with packing of the particles which is affecting to the porosity and thus to the strength. The platy kaolin packs up much better than others and creates less porous structure. The results also showed that the binder properties have a great effect to the compressive strength of coating layer. The amount of latex and the glass transition temperature, Tg, affect to the strength. As the amount of latex is increasing, the strength of coating is increasing also. Larger amount of latex is binding the pigment particles better together and decreasing the porosity. Compressive strength was increasing when the Tg was increasing because the hard latex gives a stiffer and less elastic film than soft latex.

Hydraulic and fluvial geomorphological models for a bedrock channel reach of the Twenty Mile Creek /

Bedrock channels have been considered challenging geomorphic settings for the application of numerical models. Bedrock fluvial systems exhibit boundaries that are typically less mobile than alluvial systems, yet they are still dynamic systems with a high degree of spatial and temporal variability. To understand the variability of fluvial systems, numerical models have been developed to quantify flow magnitudes and patterns as the driving force for geomorphic change. Two types of numerical model were assessed for their efficacy in examining the bedrock channel system consisting of a high gradient portion of the Twenty Mile Creek in the Niagara Region of Ontario, Canada. A one-dimensional (1-D) flow model that utilizes energy equations, HEC RAS, was used to determine velocity distributions through the study reach for the mean annual flood (MAF), the 100-year return flood and the 1,000-year return flood. A two-dimensional (2-D) flow model that makes use of Navier-Stokes equations, RMA2, was created with the same objectives. The 2-D modeling effort was not successful due to the spatial complexity of the system (high slope and high variance). The successful 1 -D model runs were further extended using very high resolution geospatial interpolations inherent to the HEC RAS extension, HEC geoRAS. The modeled velocity data then formed the basis for the creation of a geomorphological analysis that focused upon large particles (boulders) and the forces needed to mobilize them. Several existing boulders were examined by collecting detailed measurements to derive three-dimensional physical models for the application of fluid and solid mechanics to predict movement in the study reach. An imaginary unit cuboid (1 metre by 1 metre by 1 metre) boulder was also envisioned to determine the general propensity for the movement of such a boulder through the bedrock system. The efforts and findings of this study provide a standardized means for the assessment of large particle movement in a bedrock fluvial system. Further efforts may expand upon this standardization by modeling differing boulder configurations (platy boulders, etc.) at a high level of resolution.

Mineral and geochemical characterization of a leptic aluandic soil and a thapto aluandic-ferralsol developed on trachytes in Mount Bambouto (Cameroon volcanic line)

Mineral and geochemical investigations were carried out on soil samples and fresh rock (trachytes) from two selected soil profiles (TM profile on leptic aluandic soils and TL profile on thapto aluandic-ferralsols) from Mount Bambouto to better understand geochemical processes and mineral paragenesis involved in the development of soils in this environment. In TM profile, the hydrated halloysites and goethite occur in the weathered saprolite boulders of BC horizon while dehydrated halloysite, gibbsite and goethite dominate the soils matrices of BC and A horizons. In TL profile, the dehydrated halloysites and goethite are the most abundant secondary minerals in the weathered saprolites of C and BC horizons while gibbsite, hematite and kaolinite occur in the soil matrices of BC, B and A horizons. The highest gibbsite content is in the platy nodules of B horizon. In both soil profiles, organo-metal complexes (most likely of AI and Fe) are present in the surface A horizon. Geochemically, between the fresh rock and the weathered saprolites in both soils, SiO2, K2O, CaO, Na2O and MgO contents decrease strongly while Fe2O3 and Al2O3 tend to accumulate. The molar ratio of SiO2/Al2O3 (Ki) and the sum of Ca, Mg, K and Na ions (TRB) also decreases abruptly between fresh rocks and the weathered saprolites, but increases significantly at the soil surface. The TM profile shows intense Al enrichment whereas the TL profile highlights enrichment in both AI and Fe as the weathering progresses upwards. Both soil profiles are enriched in Ni, Cu, Ba and Co and depleted in U, Th, Ta, Hf, Y, Sr, Pb, Zr and Zn relative to fresh rock. They also show a relatively low fractionation of the rare earth elements (REE: La, Nd, Sm, Eu, Tb, Yb and Lu), except for Ce which tends to be enriched in soils compared to CI chondrite. All these results give evidence of intense hydrolysis at soil deep in Mount Bambouto resulting in the formation of halloysite which progressively transforms into gibbsite and/or dehydrated halloysite. At the soil surface, the prominent pedogenetic process refers to andosolization with formation of organo-metal complexes. In TL profile, the presence of kaolinite in soil matrices BC and B horizons is consistent with ferralitization at soil deep. In conclusion, soil forming processes in Mount Bambouto are strongly influenced by local climate: (i) in the upper mountain (>2000 m), the fresh, misty and humid climate favors andosolization; whereas (ii) in the middle lands (1700-2000 m) with a relatively dry climate, both andosolization at the soil surface and ferralitization at soil deep act together. (C) 2009 Elsevier B.V. All rights reserved.

Crystallization of nordstrandite in ethylene glycol water solutions: electron microscopic studies

The present work shows the growth of nordstrandile microcrystals observed by transmission and scanning electron microscopy. Nordstrandite was synthesised from non-crystalline aluminium hydroxide reacted in 20% ethylene glycol/water solution, at room temperature. This material was characterized by TEM, SEM, SAED, XRD and EDS/TEM, during six month and revealed the formation and growth of nordstrandite. Fibrillar pseudoboehmite is the only aluminium hydroxide which could be identified during the first two weeks. The nuclei grow, from complete dissolution/recrystallization of pseudoboehmite fibrils, into platy rectangular microscrystals of nordstrandite. Some tabular microcrystals recrystallise, forming after six months only the mufti-point nordstrandite stars. This electron-optical study suggest that the star shape results from the overlapping of rectangular plates, and pseudoboehmite fibrils act as the precursor of nordstrandite crystallisation in ethylene glycol/water solution.

Brumadoite, a new copper tellurate hydrate, from Brumado, Bahia, Brazil

Brumadoite, ideally Cu(2)Te(6+)O(4)(OH)(4)center dot 5H(2)O, is a new mineral from Pedra Preta mine, Serra das Eguas, Brumado, Bahia, Brazil. It occurs as microcrystalline aggregates both on and, rarely, pseudomorphous after coarse-grained magnesite, associated with mottramite and quartz. Crystals are platy, subhedral, 1-2 mu m in size. Brumadoite is blue (near RHS 114B), has a pale blue streak and a vitreous lustre. It is transparent to translucent and does not fluoresce. The empirical formula is (Cu(2.90)Pb(0.04)Ca(0.01))(Sigma 2.95) (Te(0.93)(6+)Si(0.05))(Sigma 0.98)O(3.92)(OH)(3.84)center dot 5.24H(2)O. Infrared spectra clearly show both (OH) and H(2)O. Microchemical spot tests using a KI Solution show that brumadoite has tellurium in the 6(+) state. The mineral is monoclinic, P2(1)/m or P2(1). Unit-cell parameters refined from X-ray powder data are a 8.629(2) angstrom, b 5.805(2) angstrom, c 7.654(2) angstrom, beta 103.17(2)degrees, V 373.3(2) angstrom(3), Z = 2. The eight strongest X-ray powder-diffraction lines [d in angstrom, (l),(hkl)] are: 8.432,(100),(100); 3.162,(66),((2) over bar 02); 2.385,(27),(220); 2.291,((1) over bar 12),(22); 1.916,(11),(312); 1.666,(14),((4) over bar 22,114); 1.452,(10), (323, 040); 1.450,(10),(422,403). The name is for the type locality, Brumado, Bahia, Brazil. The new mineral species has been approved by the CNMNC (IMA 2008-028).

Protozoan parasites of Xiphophorus spp. (Poeciliidae) and their relation with water characteristics

Investigou-se a relação entre as características da água e a infestação de protozoários parasitos, Icthyophthirius multifiliis e Trichodina sp., em peixe espada, Xiphophorus helleri e em plati, Xiphophorus maculatus, coletados em uma piscicultura de peixes ornamentais no Estado de São Paulo, Brasil. Os peixes foram coletados mensalmente, durante um ano, dos viveiros e das caixas de estocagem. A prevalência da infestação nos peixes das caixas e dos viveiros foram, respectivamente, 34,2% e 22,5% para I. multifiliis e 13% e 54% para Trichodina sp. A elevada condutividade elétrica e o pH da água reduziram a infestação por I. multifiliis. A baixa concentração de oxigênio resultou em aumento na infestação por Trichodina sp. O uso do sal, para aumentar a condutividade elétrica da água, consistiu em um método de controle de I. multifiliis. A redução do oxigênio dissolvido e a adição de fertilizante orgânico favoreceram a reprodução de Trichodina sp.

Crystallization of nordstrandite in ethylene glycol water solutions: electron microscopic studies

The present work shows the growth of nordstrandile microcrystals observed by transmission and scanning electron microscopy. Nordstrandite was synthesised from non-crystalline aluminium hydroxide reacted in 20% ethylene glycol/water solution, at room temperature. This material was characterized by TEM, SEM, SAED, XRD and EDS/TEM, during six month and revealed the formation and growth of nordstrandite. Fibrillar pseudoboehmite is the only aluminium hydroxide which could be identified during the first two weeks. The nuclei grow, from complete dissolution/recrystallization of pseudoboehmite fibrils, into platy rectangular microscrystals of nordstrandite. Some tabular microcrystals recrystallise, forming after six months only the mufti-point nordstrandite stars. This electron-optical study suggest that the star shape results from the overlapping of rectangular plates, and pseudoboehmite fibrils act as the precursor of nordstrandite crystallisation in ethylene glycol/water solution.

Protozoan parasites of Xiphophorus spp. (Poeciliidae) and their relation with water characteristics

Investigou-se a relação entre as características da água e a infestação de protozoários parasitos, Icthyophthirius multifiliis e Trichodina sp., em peixe espada, Xiphophorus helleri e em plati, Xiphophorus maculatus, coletados em uma piscicultura de peixes ornamentais no Estado de São Paulo, Brasil. Os peixes foram coletados mensalmente, durante um ano, dos viveiros e das caixas de estocagem. A prevalência da infestação nos peixes das caixas e dos viveiros foram, respectivamente, 34,2% e 22,5% para I. multifiliis e 13% e 54% para Trichodina sp. A elevada condutividade elétrica e o pH da água reduziram a infestação por I. multifiliis. A baixa concentração de oxigênio resultou em aumento na infestação por Trichodina sp. O uso do sal, para aumentar a condutividade elétrica da água, consistiu em um método de controle de I. multifiliis. A redução do oxigênio dissolvido e a adição de fertilizante orgânico favoreceram a reprodução de Trichodina sp.

Assessing visual disturbance conditions on the Custer National Forest

Assessment of soil disturbance on the Custer National Forest was conducted during two summers to determine if the U.S. Forest Service Forest Soil Disturbance Monitoring Protocol (FSDMP) was able to distinguish post-harvest soil conditions in a chronological sequence of sites harvested using different ground-based logging systems. Results from the first year of sampling suggested that the FSDMP point sampling method may not be sensitive enough to measure post-harvest disturbance in stands with low levels of disturbance. Therefore, a revised random transect method was used during the second sampling season to determine the actual extent of soil disturbance in these cutting units. Using combined data collected from both summers I detected statistically significant differences (p < 0.05) in fine fraction bulk density measurements between FSDMP disturbance classes across all sites. Disturbance class 3 (most severe) had the highest reported bulk density, which suggest that the FSDMP visual class estimates are defined adequately allowing for correlations to be made between visual disturbance and actual soil physical characteristics. Forest site productivity can be defined by its ability to retain carbon and convert it to above- and belowground biomass. However, forest management activities that alter basic site characteristics have the potential to alter productivity. Soil compaction is one critical management impact that is important to understand; compaction has been shown to impede the root growth potential of plants, reduce water infiltration rates increasing erosion potential, and alter plant available water and nutrients, depending on soil texture. A new method to assess ground cover, erosion, and other soil disturbances was recently published by the U.S. Forest Service, as the Forest Soil Disturbance Protocol (FSDMP). The FSDMP allows soil scientists to visually assign a disturbance class estimate (0 – none, 1, 2, 3 – severe) from field measures of consistently defined soil disturbance indicators (erosion, fire, rutting, compaction, and platy/massive/puddled structure) in small circular (15 cm) plots to compare soil quality properties pre- and post- harvest condition. Using this protocol we were able to determine that ground-based timber harvesting activities occurring on the Custer National Forest are not reaching the 15% maximum threshold for detrimental soil disturbance outlined by the Region 1 Soil Quality Standards.

Age and petrographic characterization of volcanic ash from ODP Leg 198 and Leg 126 sites

In this study of volcanic ash retrieved from Shatsky Rise during Ocean Drilling Program Leg 198, the texture and composition of the volcanic components (glass and crystals) were used to fingerprint ash layers for detailed correlation. Correlations among ash layers in holes drilled at the same site as well as between sites, including sites on different parts (highs) of the rise, were tested. Although high-to-high correlations failed, intrahigh correlations were more successful. Our data suggest a significantly different source for some pyroclastic debris, especially at Site 1208, possibly associated with pumice rafts carried northward from the Izu-Bonin arc by the Kuroshio Current. Other ashes are consistent with rhyolitic to dacitic air fall ash from Asian arc volcanoes. We were not able to texturally distinguish between air fall ash and pumice-raft fallout but suspect that the latter is associated with higher percentages of vesiculated ash components, as we demonstrate occur in more proximal Izu-Bonin pyroclastic deposits.