Single Oil Research Articles

Effect of Punica Granatum (Pomegranate) on serum ALT and AST in Carbon tetrachloride induced liver damage in Wistar Albino Rats

Background: Liver diseases are associated with significant morbidity and mortality. Punica granatum may have free radical scavenging activity and it can be used for the prevention and treatment of liver damage.Objective: To observe the hepatoprotective effects of Punica granatum on CCl4 induced liver damage in rats.Methods: The experimental study was carried out in the Dept of Physiology, Dhaka Medical Ccollege, Dhaka from July 2013 to June 2014. For this purpose, 36 wistar albino rats were studied. After acclimatization for 7 days, they were divided into two groups-control and experimental group. Control group were subdivided into BC (Baseline control), CC (CCl4 treated control) and SC (Silymarin treated control). Experimental group were subdivided into CP-APT (CCl4 pretreated and aqueous extract of pomegranate treated), CP-EPT (CCl4 pretreated and ethanolic extract of pomegranate treated) and APP-CT (Aqueous extract of pomegranate pretreated and CCl4 treated). Each sub group consisted of 6 rats. All rats received basal diet for 8 days. In addition to basal diet on 8th day, BC received single dose olive oil and CC received CCl4. Rats of SC received silymarin for 8consecutive days. In experimental groups, CP-APT received aqueous extract of Pomegranate and CP-EPT received ethanolic extract of Pomegranate for 8consecutive days. Moreover, APP-CT received aqueous extract of Pomegranate for 8 consecutive days and CCl4 only on 8th day. All rats were sacrificed on 9th day and then blood samples were collected. Serum ALT and AST levels were estimated by using standard laboratory kits. Statistical analysis was done one way ANOVA and Bonferroni test.Results: The mean serum AST and ALT levels were significantly (p<0.001) higher in CC in comparison to those of BC. Serum AST and ALT levels of all experimental groups were significantly (P<0.001) lower than CC. Silymarin used as a standard reference also exhibited significant hepatoprotective activity against CCl4 induced hepatotoxicityConclusion: From the result of present study it can be concluded that, Pomegranate may have hepatoprotective effect by lowering ALT and AST levelsBangladesh Soc Physiol. 2016, June; 11(1): 23-28

항균작용에 대한 에센셜 오일들 간의 상승작용 탐색

본 연구에서는 피부상재균을 대상으로 단일오일의 항균효과를 살펴보는 동시에 2가지 이상의 오일을 혼합한 블랜딩 오일이 실제로 상승효과를 일으키는지 탐색해보고자 하였다. 항균실험에 사용된 에센셜 오일은 100% 유칼립투스(EU), 레몬(LE), 라벤더(LA) 오일이었으며, 2가지 오일 블랜딩의 상승효과를 알아보기 위하여 EU+LE, LE+LA, EU+LA을 1:1의 비율로, 3가지 오일 블랜딩의 상승효과를 알아보기 위해 각 오일을 1:1:1 비율로 혼합하여 배지의 표피포도상구균에 적용한 후 항균 영역 값을 평균 비교하였다. 그 결과, 단일오일에서는 LE이 가장 높은 항균력을 보였으며, LA는 가장 낮은 항균력을 보였다. 2가지오일 블랜딩에서는 EU+LA의 항균력이 단일오일의 항균력의 합보다 커 상승효과를 나타내었다. 그러나 3가지 오일 블랜딩의 항균효과는 아주 낮게 나타나 상승효과를 나타내지 않았다. 이러한 결과는 블랜딩 한 오일의 수 보다 오일을 구성하는 화학 성분들 간의 상호작용이 상승효과에 더욱 중요한 영향을 미친다는 것을 보여주었다. 따라서, 본 연구를 토대로 에센셜 오일 블랜딩에 대한 과학적 증거 마련이 더욱 필요할 것이라 사료된다. This study was conducted to look at the antimicrobial synergistic effect of blended oil into the target skin flora. The essential oils used in antimicrobial test were 100% eucalyptus (EU), lemon (LE), lavender (LA) and four blended oils, EU+LE, LE+LA, EU+LA, and, EU+LE+LA in ratio of 1:1 and 1:1:1 respectively. As a result, LE showed the highest, LA showed the lowest antimicrobial activity among single oil group. In blended oil group, antimicrobial activity of the EU + LA showed significantly increasing effect than the sum of the antimicrobial activity of the single oil. However, the antimicrobial effects of the blend of three oils did not show any synergistic effect. This result showed that the interaction between the chemical components constituting the oil than the number of blended oil seems more significant on the synergistic effect. Therefore, blending essential oil based on scientific evidence becomes more necessary in the future.

Probing Ion Transfer across Liquid-Liquid Interfaces by Monitoring Collisions of Single Femtoliter Oil Droplets on Ultramicroelectrodes.

We describe a method of observing collisions of single femtoliter (fL) oil (i.e., toluene) droplets that are dispersed in water on an ultramicroelectrode (UME) to probe the ion transfer across the oil/water interface. The oil-in-water emulsion was stabilized by an ionic liquid, in which the oil droplet trapped a highly hydrophobic redox probe, rubrene. The ionic liquid also functions as the supporting electrolyte in toluene. When the potential of the UME was biased such that rubrene oxidation would be possible when a droplet collided with the electrode, no current spikes were observed. This implies that the rubrene radical cation is not hydrophilic enough to transfer into the aqueous phase. We show that current spikes are observed when tetrabutylammonium trifluoromethanesulfonate or tetrahexylammonium hexafluorophosphate are introduced into the toluene phase and when tetrabutylammonium perchlorate is introduced into the water phase, implying that the ion transfer facilitates electron transfer in the droplet collisions. The current (i)-time (t) behavior was evaluated quantitatively, which indicated the ion transfer is fast and reversible. Furthermore, the size of these emulsion droplets can also be calculated from the electrochemical collision. We further investigated the potential dependence on the electrochemical collision response in the presence of tetrabutylammonium trifluoromethanesulfonate in toluene to obtain the formal ion transfer potential of tetrabutylammonium across the toluene/water interface, which was determined to be 0.754 V in the inner potential scale. The results yield new physical insights into the charge balance mechanism in emulsion droplet collisions and indicate that the electrochemical collision technique can be used to probe formal ion transfer potentials between water and solvents with very low (ε < 5) dielectric constants.

Gross nitrogen transformation rates differ in reconstructed oil-sand soils from natural boreal-forest soils as revealed using a 15N tracing method

The Athabasca Oil Sands deposit is one of the largest single oil deposits in the world. Following surface mining, companies are required to restore soil-like profiles that can support the previous land capabilities. Re-establishment of nutrient cycles in reconstructed soils is one of the most critical factors in ensuring long-term sustainability of these reconstructed boreal landscapes. We compared soils from nine reconstructed oil-sand sites with those from three natural boreal-forest sites of similar age since wildfire disturbance. We (1) measured soil total N, NH4+, and NO3− content; (2) quantified gross N transformation rates in reconstructed and natural soils using a 15N tracing method; (3) compared gross rates of N transformations in reconstructed soils under different vegetation types to compared N-cycling processes in these soils. The 15N tracing approach highlighted key distinctions in N-cycling processes in reconstructed and natural soils. In reconstructed soils, NH4+ was mainly cycled through the recalcitrant organic-N pool, whereas in natural soils, NH4+ was produced from the recalcitrant organic-N pool but predominantly consumed in the labile organic-N pool. The mineralization of NH4+ from the labile organic-N pool was also higher in natural soils compared to reconstructed soils, suggesting greater prominence of microbial N-cycling activity in the natural soils compared to the reconstructed soils. Gross nitrification rates were similar in natural and reconstructed soils, but net nitrification rates were higher and apparently of heterotrophic origin in reconstructed soils. The higher net nitrification rates in reconstructed soils indicate a surplus of N relative to microbial requirements in reconstructed soils. N-transformation rates were similar in reconstructed soils under the three types of vegetation.

Dibenzothiophenes and benzonaphthothiophenes in oils, and their application in identifying oil filling pathways in Eocene lacustrine clastic reservoirs in the Beibuwan Basin, South China Sea

Dibenzothiophenes (DBTs) and benzo[b]naphthothiophenes (BNTs) are important sulfur heterocyclic aromatic compounds in oils and sedimentary rock extracts. Based on both migration fractionation effects and differences in thermal stability of different isomers, DBTs and BNTs can be used to trace oil migration orientations and filling pathways. They are present in significant abundances in oils, including light oils and condensates, in which biomarkers are commonly absent or present only in extremely low concentrations. Molecular biomarker compositions indicate that all oils and condensates in the Eocene clastic reservoir of the Fushan Depression (Beibuwan Basin, South China Sea) belong to a single oil population. In this study, three geochemical indicators relating to DBTs and BNTs, namely; (1), 4-/1-methyldibenzothiophene (4-/1-MDBT); (2), total content of DBTs; and (3), benzo[b]naphtha[2,1-d]thiophene/(benzo[b]naphtha[2,1-d]thiophene+benzo[b]naphtho[1,2-d]thiophene) ([1,2]BNT/([1,2]BNT+[1,2]BNT)) were applied to trace oil migration orientations and filling pathways. The results show that these parameter values gradually decrease from northeast to southwest, towards the Huachang Uplift, and from north to south towards the Bailian Faulted-Belts. Therefore, the source kitchen for identified oil accumulations in the Huachang Uplift is likely to be located in the Bailian Sag, which lies to the northeast of the Huachang Uplift. Zones in the Bailian Sag, situated upstream of the preferred oil filling pathways are likely to be the most favorable prospecting regions. It is concluded that relative parameters of DBTs and BNTs are practical molecular indicators for tracing oil migration orientations and filling pathways.

Theoretical study of R32 in an oil flooded compression cycle with a scroll machine

R32 is regarded as a potential alternative for R410A, but it has a low slope of isentropic line, high superheat inside a compressor and thus a high discharge temperature. These disadvantages limit its wider adoption. In order to improve the performance of R32 air conditioner, oil flooded compression with regenerator has been suggested. A single stage oil flooded compressor model is developed to obtain a more accurate system-level improvement. In the compressor model, the heat transfer losses between shell and ambient, suction gas and motor, and high-pressure and low-pressure cylinders are considered. By means of parametric studies, it was found that the novel cycle resulted to be beneficial to increase the compressor internal superheating, to decrease the compressor heat losses and to improve its overall isentropic efficiency while cooling capacity or heating capacity is degraded. COPh improvement can reach up to 16.4% for an evaporating and condensing temperatures of −25 °C and 45 °C, respectively. The discharge temperature resulted to be lower than 110 °C. In addition, a thorough comparison between R32 and R410A with both novel and baseline systems has been carried out. The results indicate that the novel cycle has potential benefits for applications in R32 air conditioners.

Egypt far Western Desert basins petroleum charge system as defined by oil chemistry and unmixing analysis

Source rock analysis and maturity modeling in Egypt’s Far Western Desert basins indicates that several Jurassic and Cretaceous petroleum source rocks could be mature and expelling hydrocarbons over much of the area. Highly variable oil characteristics suggest that more than one charge system may be present. Reservoir crude oil chemistry indicates that the fluids originated from a single source facies generated over a wide range of organic maturity. Secondary alteration mechanisms include water washing, biodegradation, and evaporative fractionation. Crude oils in the upper reservoirs tend to be most affected by biodegradation and water washing. Condensates and light crude oils in the deepest reservoirs appear to be the residual phase from evaporative fractionation.The broad variation in fluid properties and chromatogram character can be attributed to a multi end-member mixing system: early mature waxy oil, later high maturity volatile oil, low level biodegradation, migrated phase evaporative fractionation, and residual phase evaporative fractionation. A statistical “unmixing” algorithm was used to determine end-member compositions and relative mixing proportions for each crude oil sample. Remigration and mixing of the products from multi-phase generation and alteration results in complex reservoir fluid compositions, such that no single reservoired oil represents a compositional end-member, rather the oil samples are mixtures of various amounts of multiple end-members. Mixing proportions show regional trends and variations in different reservoirs within a single field. The crude oil geochemical data and unmixing analysis support a complex charge history from a single source rock, rather than mixing of oils from two source rocks.

Potential hybrid feedstock for biodiesel production in the tropics

Recently, mixture of different oils at various proportions have been used as feedstock for biodiesel production. The primary aim is to improve fuel properties which are strongly influenced by the fatty acid composition of the individual oil that makes up the feedstock mix. The tropics are renowned for abundant oil-bearing crops of which palm kernel oil (PKO) from palm seed and groundnut oil (GNO) are prominent. This present paper investigated biodiesel production from hybrid oil (HO) of PKO (medium carbon chain and highly saturated oil) and GNO (long carbon chain and highly unsaturated oil) at 50/50 (v/v) blending. The principal fatty acids (FAs) in the HO are oleic (35.62%) and lauric acids (24.23%) with 47.80% of saturated FA and 52.26% of unsaturated FA contents. The chemical conversion of the oil to methyl ester (ME) gave 86.56% yield. Fuel properties of hybrid oil methyl ester (the HOME) were determined in accordance with standard test methods and were found to comply with both ASTM D6751 and EN 14214 standards. The oxidative stability, cetane number and kinematic viscosity (KV) of HOME were observed to be improved when compared with those of GNO methyl ester from single parent oil, which could be accredited to the improved FA composition of the HO. The KV (3.69 mm2/s) of HOME obtained in this paper was remarkably low compared with those reported in literature for most biodiesels. This value suggests better flow, atomization, spray and combustion of this fuel. Conclusively, the binary blend of oils can be a viable option to improve the fuel properties of biodiesel feedstock coupled with reduced cost.

A detection method of vegetable oils in edible blended oil based on three-dimensional fluorescence spectroscopy technique

Edible blended vegetable oils are made from two or more refined oils. Blended oils can provide a wider range of essential fatty acids than single vegetable oils, which helps support good nutrition. Nutritional components in blended oils are related to the type and content of vegetable oils used, and a new, more accurate, method is proposed to identify and quantify the vegetable oils present using cluster analysis and a Quasi-Monte Carlo integral. Three-dimensional fluorescence spectra were obtained at 250–400nm (excitation) and 260–750nm (emission). Mixtures of sunflower, soybean and peanut oils were used as typical examples to validate the effectiveness of the method.

Secondary Angle-Closure Glaucoma Due to Posterior Synechiae of Iris Following Combined Phacoemulsification and 23-Gauge Transconjunctival Vitrectomy

ABSTRACTPurpose: To describe the clinical characteristics of eyes with secondary angle-closure glaucoma following combined phacovitrectomy. Methods: Retrospective case series. Results: Nine eyes developed angle-closure glaucoma due to iris posterior synechiae with an incidence rate of 1.82% (95% CI: 0.64 – 3%) among 493 eyes following phacovitrectomy. PDR with TRD was the most common surgical indication. Single piece IOL insertion and silicone oil were present in all cases. Fibrin in the anterior chamber was found in six eyes postoperatively. Mean degree of iris bombe was 310±79.37° at 3.55±1.87 weeks with a mean IOP of 32.56±5.89 mm of Hg. Systemic diabetes and grade of cataract were the only significant risk factors (r2 =1; p= 0.016 and 0.049, respectively). Nd:YAG laser PI relieved the angle-closure attack in all cases. Conclusion: Systemic diabetes and advanced grade of cataract are significant risk factors for secondary angle-closure glaucoma following combined phacovitrectomy.

Trait selection by path and principal component analysis in Jatropha curcas for enhanced oil yield

Path analysis was done on different morphological, physiological and oil quality traits of 15, six-years old candidate plus trees of Jatropha curcas to assess their direct and indirect effect on oil yield. Principal component analysis was subsequently done to assess the pattern of the variations in characters and segregate the traits to distinguish parental accessions for plant improvement. Total chlorophyll had a positive direct effect on oil yield and also had indirect effect through single seed weight, single fruit weight and oil content. Male to female flower ratio had negligible direct effect on oil yield but had considerable indirect effect through seed yield per plant. Seed weight, fruit weight and seed yield plant−1 had a high direct effect on oil yield and also had indirect effect through oil content and thus found suitable for direct selection. The first five principal components contributed 75.5% of the total variability. The accessions JCN14, JCN08 and JCN09 had very high values for the first component, while JCN04 and JCN05 had lower values for all these variables.

Development of eggs and larvae of Stolephorus commersonnii and taxonomic key to fish eggs of the Clupeidae and Engraulidae off China

ABSTRACTFish eggs of successive stages of embryonic development, which were identified as belonging to specimens of Commerson's anchovy Stolephorus commersonnii through comparative molecular techniques, were collected from Leqing Bay, Zhejiang, China. Some eggs were reared artificially to obtain samples of successive developmental stages of larvae. The fertilized eggs of S. commersonnii are ellipsoidal and non-adhesive. The surface of the egg membrane is smooth and the perivitelline space is narrow. There is a single oil globule in the irregularly segmented yolk. Newly hatched larvae are transparent and devoid of pigments. Development of the larvae occurs in the following sequence: 8 h after hatching, the anus unfolds; 12 h after hatching, the pectoral fins emerge; 24 h after hatching, the liver and branchial arches emerge, and the alimentary canal differentiates into the oesophagus and intestinal canal; 30 h after hatching, the eyes become pigmented; 36 h after hatching, the upper and lower jaws become distinct; 42 h after hatching, the stellate melanophores emerge; 72 h after hatching, the postlarval developmental stage begins with the emergence of the dorsal fin. Based on the morphology of eggs and larvae of S. commersonnii, a taxonomic key to fish eggs of the Clupeidae and Engraulidae off China is established to provide an efficient and convenient way to identify the egg specimens. The fish eggs of the Clupeidae and Engraulidae off China could be identified to some extent by the buoyancy, shape and diameter of eggs, the number of layers in the egg membrane, the size of the perivitelline space, the number and diameters of oil globules, and the distribution of pigments. Meanwhile, their prelarvae could be identified by the number and diameters of oil globules, the distribution of pigments, the location of the anus and the number of myomeres.

The effectiveness of nurse-delivered aromatherapy in an acute care setting

ObjectiveTo examine the use and effectiveness of essential oil therapeutic interventions on pain, nausea, and anxiety, when provided by nurses to patients in acute hospital settings across a large health system. This study expands upon the limited body of literature on aromatherapy use among inpatients. DesignRetrospective, effectiveness study using data obtained from electronic health records. SettingTen Allina Health hospitals located in Minnesota and western Wisconsin. InterventionsNurse-delivered aromatherapy. Main Outcome MeasuresChange in patient-reported pain, anxiety, and nausea, rated before and after receiving aromatherapy using a numeric rating scale (0–10). ResultsThere were 10,262 hospital admissions during the study time frame in which nurse-delivered aromatherapy was part of patient care. The majority of admissions receiving aromatherapy were females (81.71%) and white (87.32%). Over 75% of all aromatherapy sessions were administered via inhalation. Lavender had the highest absolute frequency (49.5%) of use regardless of mode of administration, followed by ginger (21.2%), sweet marjoram (12.3%), mandarin (9.4%), and combination oils (7.6%). Sweet marjoram resulted in the largest single oil average pain change at −3.31 units (95% CI: −4.28, −2.33), while lavender and sweet marjoram had equivalent average anxiety changes at −2.73 units, and ginger had the largest single oil average change in nausea at −2.02units (95% CI: −2.55, −1.49). ConclusionsEssential oils generally resulted in significant clinical improvements based on their intended use, although each oil also showed ancillary benefits for other symptoms. Future research should explore use of additional essential oils, modes of administration, and different patient populations.

A direct method for property estimation from analysis of infinite acting production in shale/tight gas reservoirs

Abstract Infinite acting linear flow is a dominant flow regime in many multi-fractured horizontal wells completed in shale/tight gas reservoirs. A well-accepted methodology for analysis of this flow regime in systems without aquifer influence is the square-root of time plot. For reservoirs producing single phase oil, fracture half-length can be estimated from the slope of this plot, provided reservoir permeability is known. However, for gas reservoirs, pseudovariables are required to account for the pressure-dependence of gas properties. For example, the pseudotime function must be used to account for the strong dependence of gas viscosity and compressibility on pressure. As has been previously noted, for tight reservoirs, the pseudotime function must be evaluated at average pressure in the region of influence, which in turn is calculated from the material balance equation. Therefore, the linear flow equation should be coupled with the material balance equation so that fracture half-length can be estimated. This solution methodology is implicit and may require iterative procedures. This paper introduces an explicit solution methodology for estimating fracture half-length. As in the case of implicit solution methodology, the assumptions of no aquifer influence and infinite acting flow are considered. Because of no aquifer support, we can use material balance equation of volumetric reservoirs. We propose an appropriate correlation between viscosity–compressibility product and the material balance equation. This correlation helps to simplify pseudotime calculations and remove the implicit and iterative nature of the previous solution methodology. Accordingly, we have developed simple semi-analytic solutions that provide a methodology for direct estimation of fracture half-length. The solutions were developed for constant rate, constant pressure, and variable pressure/rate production from wells. We used numerical simulation to generate many synthetic production examples with wide ranges in reservoir properties to validate the introduced equations. We further used our approach for analysis of field cases (multi-fractured horizontal wells completed in shale reservoirs) to demonstrate its practical applicability to real data.

Oil filling history of the Mesozoic oil reservoir in the Tabei Uplift of Tarim Basin, NW China

Abstract The Tabei Uplift is one of the largest petroleum accumulation region in China. After decades of exploration and development a number of commercial oil reservoirs have been discovered in the Mesozoic formations suggesting a great potential for hydrocarbons. The Mesozoic oils were sampled from 18 wells in the Tabei Uplift. A total of 6 Ordovician oil samples were also collected for contrast analysis. On the basis of oil–oil correlation, all of the 24 crude oils belong to the same oil population and probably derived from the same source kitchen. Despite the coexistence of “UCM”,25-norhopane and intact n -alkanes which is generally interpreted as twice oil filling history, the homogenization temperature ( T h ) of brine inclusion indicates a single oil filling event which happened at 4–3 Ma, with the major frequency ranging from 110 °C to 120 °C. By means of T s /( T s + T m ), MPI−1, 4-/1-MDBT and total concentration of carbazole compounds, the oil filling orientation in Yakela and Yuqi areas were from NEE to SWW and NW to SE, respectively. The Luntai fault is believed to be an oil-migrating fault connecting the Ordovician reservoirs with Mesozoic reservoirs. Based on the physical properties, the geochemical characteristics and the oil filling histories, it can be concluded that the Mesozoic reservoirs in the Tabei Uplift were of secondary oil accumulations derived from the deeper Ordovician reservoirs.

An interwell connectivity inversion model for waterflooded multilayer reservoirs

Abstract In view of the limitations that the current connectivity model can only forecast the fluid production dynamic change, can't calculate the dynamics of oil and water phases, and can't analyze the connectivity between wells layer by layer, this study establishes a new interwell connectivity model for multilayer reservoirs which can simulate dynamics of oil and water between wells. The model hierarchically separates the reservoir system into a series of interwell connecting units characterized by parameters such as conductivity and control volume, and by using the material balance equation, the pressure and interwell flow at constant liquid production or constant pressure mode is calculated regarding the connecting unit as a simulation object, which are combined with the frontal advance theory to establish interwell saturation tracking calculation, and finally water production dynamics of every layer at well points can be worked out. On this basis, using simultaneous perturbation stochastic approximation method and gradient projection method, a model parameter inversion method is set up by dynamic fitting. The application cases show that the model has good dynamic fitting and prediction effect, inversed model parameters coincide with the actual geological parameters, verifing the validity of the method. Compared with the current connectivity method, it can obtain the real-time model of hierarchical interwell flow rate distribution coefficient, liquid production of single well and oil split coefficient and other information, and reflect the reservoir horizontal and vertical oil-water flow relation more accurately, providing guidance for production measure adjustment in oilfield.

Re–Os dating of maltenes and asphaltenes within single samples of crude oil

Re–Os geochronology of oil may constrain the timing of oil formation and improve oil-source and oil–oil correlations. Typically, asphaltene (ASPH), the heaviest and most Re–Os rich oil fraction, from multiple oils within an oil field or a larger petroleum system are analyzed to obtain sufficient spread in Re–Os isotopic ratios, a mathematical necessity for precise Re–Os isochrons.Here we offer a new approach for Re–Os geochronology of oil based on isotopic analyses of different fractions within a single sample of crude oil. We studied three oils from the Gela oil field, southern Sicily, Italy, recovered from Triassic–Jurassic stratigraphic intervals (Streppenosa, Noto, and Sciacca Formations) within the Gela-1 well. ASPH (insoluble in n-alkane) and maltene (MALT, soluble in n-alkane) fractions of oil were separated using n-pentane, n-hexane, n-heptane and n-decane solvents. The ASPH contents of the Sciacca and Noto oils (26–33wt%) are notably higher compared to the Streppenosa oil (7–12wt% ASPH).We present an optimized Re–Os procedure with sample digestion in a high-pressure asher, followed by isotopic measurements using negative thermal ionization mass spectrometry. Very high metal contents of Gela oils allowed acquisition of precise Re–Os data. Systematic variations between the type of solvent used for ASPH precipitation and the ASPH content of the oil (also known from the literature) and the Re–Os contents of the ASPH and MALT fractions (first observed in this study) provide important practical applications for Re–Os analyses of oil. Most Re and Os (∼96–98%) in the Noto oil are hosted in the ASPH fraction. In contrast, a significant portion of Re and Os (∼33–34%) is stored in the MALT fraction of the lighter, but heavily biodegraded Streppenosa oil.Collectively, our new data on alkane distribution, hopane and sterane biomarkers, major and trace element contents, and Re–Os concentrations and isotopic ratios of the oils and their fractions support the presence of two oil families. Streppenosa oil, a heavily biodegraded oil generated at an early stage of thermal maturation from a shaly source rock, is clearly distinct from the Noto and Sciacca oils, both generated at peak maturation from a carbonate source rock with no subsequent biodegradation.Two Re–Os ages were obtained. Crude oil and ASPH from Noto and Sciacca oil yield a Model 1 isochron age of 27.5±4.6Ma with an initial 187Os/188Os of 3.89±0.43 (MSWD=1.6, n=19). We interpret this Oligocene age as the time of initial oil generation, that was probably related to the onset of regional collisional tectonics in southern Sicily. ASPH and crude oil from the Streppenosa oil yield scattered data, perhaps related to effects of biodegradation. Streppenosa MALT yield a Model 1 age of 200.0±5.2Ma and initial 187Os/188Os of 1.39±0.11 (MSWD=0.52; n=4). This age and initial Os-isotopic composition are consistent with rapid oil generation shortly after Late Triassic source-rock formation, perhaps driven by magmatic-related heating.Here we document a potentially powerful geochronological tool that can be applied to single samples of crude oil. Within each oil, the 187Os/188Os and most of the 187Re/188Os ratios in the MALT fractions are lower than in the corresponding ASPH fractions. Crude oils, being physical mixtures of ASPH and MALT, have intermediate Re–Os isotopic ratios. Hence, the needed spread in data points for a Re–Os isochron is obtained by analyzing components of a single crude oil. This approach eliminates pitfalls in interpretation of Re–Os data from multiple oils with possibly different generation, migration, or reservoir modification history.

Ontogeny and growth of early life stages of captive-bred European eel

Captive breeding of European eel, Anguilla anguilla is challenged by the complex hormonal control of Anguillid eel reproduction and the distinctive ontogeny of the leptocephalus larvae that are unique to the Elopomorph superorder. Recent experimental research has succeeded in the production of viable eggs and larvae of European eel, providing the basis for studies on early life stages of this species in captivity. In this study, we describe and illustrate morphological characteristics of eggs, embryos, and larvae from fertilization to termination of the yolk sac stage and provide a comparison with additional commercially important eel species. Furthermore, we model growth during the critical first phase in larval ontogeny, i.e. the yolk sac stage, and test for maternal effects. The eggs of A. anguilla typically have numerous oil droplets that coalesce into a single large oil droplet, while the zygote forms a large perivitelline space, reaching an egg diameter of 1.45±0.12mm at 3.0 to 3.5h post fertilization. Embryonic development from fertilization to larval hatch lasted ~46–48h at 20°C with the larvae emerging in a relatively undeveloped stage with a protuberant yolk sac. During the period of yolk and oil absorption, the larvae undertook significant changes in head and body morphology. At the completion of yolk sac absorption, the largely transparent larvae had a set of protruding teeth, pigmented eyes and tail, and a simple alimentary tract. Larvae appeared capable of feeding at ~12days post hatch at 20°C, and were able to survive another ~10days without feeding. Larval length approached an asymptotic maximum of 6.8mm around day 10 in non-fed larvae. Larval batches from different maternal origins varied in yolk sac size and the extent of yolk sac resources influenced larval size at the end of the yolk sac stage. The ontogenetic description presented here fills a gap in knowledge about the yet undiscovered early life stages of native European eel, which can provide a framework of reference for the development of hatchery technology. Such progress is urgently needed for a self-sustained aquaculture of this high-value and critically endangered species. Statement of relevanceEuropean eel is a high-value species in aquaculture, however, production is presently hampered by reliance on wild caught fry. Captive production of glass eels will reopen markets in Europe and Asia, benefiting European eel producers. The results presented here document recent progress within assisted reproduction and larval culture of this species in aquaculture and aid establishing hatchery technology of this species.

Giant pH-responsive microgel colloidosomes: preparation, interaction dynamics and stability.

The interactions of two oil droplets grown in the presence of swollen, lightly cross-linked cationic poly(tert-butylamino)ethyl methacrylate (PTBAEMA) microgels was monitored using a high-speed video camera. Three oils (n-dodecane, isopropyl myristate and sunflower oil) were investigated, each in the absence and presence of an oil-soluble cross-linker [tolylene 2,4-diisocyanate-terminated poly(propylene glycol), PPG-TDI]. Adsorption of the swollen microgel particles was confirmed by interfacial tension, interfacial elasticity and dilational viscosity measurements on single pendant oil droplets, and assessment of the oscillatory dynamics for coalescing droplet pairs. Like the analogous bulk emulsions, particle adsorption alone did not prevent coalescence of pairs of giant Pickering emulsion droplets. However, prior addition of surface-active PPG-TDI cross-linker to the oil phase results in the formation of highly stable microgel colloidosomes via reaction with the secondary amine groups on the PTBAEMA chains. Colloidosome stability depended on the age of the oil-water interface. This reflects a balance between the adsorption kinetics of the PPG-TDI cross-linker and the microgel particles, each of which must be present at the interface to form a stable colloidosome. Colloidosome formation was virtually instantaneous in n-dodecane, but took up to 120 s in the case of isopropyl myristate. The impact of an acid-induced latex-to-microgel transition on the interaction of giant colloidosomes (originally prepared at pH 10 using isopropyl myristate) was also studied. This acid challenge did not result in coalescence, which is consistent with a closely-related study (A. J. Morse et al., Langmuir, 2014, 30(42), 12509-12519). No evidence was observed for inter-colloidosome cross-linking, which was attributed to retention of an aqueous film between the adjacent pair of colloidosomes.

INDUCCION DEL DESOVE, DESARROLLO EMBRIONARIO Y LARVAL DE Chaetodipterusfaber (BROUSSONET) (PISCES, EPHIPPIDAE) EN LA ISLA MARGARITA, VENEZUELA

The paguara Chaetodipterus faber (Broussonet, 1782) is a species of economic importance in the South Caribbean. Juveniles were collected near sandy beaches of Margarita Island (Venezuela) and maintained in pompano cage cultures until they reached maturation of their gonads. Adults were selected and spawning was induced by means of gonadotropin hormones. The eggs of Chaetodipterus faber are spherical, transparent and bouyant, with a diameter of 0.9 - 1.1 mm and a single globule oil of 0.25 - 0.35 mm diameter. Hatching of C. faber eggs took place within 26 h at temperatures of 24.5 - 28.5°C (31-32 h at 20-23.5°C) and salinities between 37.5 - 38.5°/oo. Newly hatched larvae vary in length from 1.9 to 2.1 mm and have a yolk sac of 1.1. - 1.3 mm in total length which is deploted after two or three days. The larval phase was completed 25 days after hatching. Juveniles 45 days old have 17.17 ± 1.75 mm in total length and weigh 0.21 + 0.07 g. Development of eggs and larvae are described.