Evaluation of the diagnostic ratios for the identification of spilled oils after biodegradation

Biodegradation, one of the most important weathering processes, alters the composition of spilled oil, making it difficult to identify the source of the release and to monitor its fate in the environment. A laboratory experiment was conducted to simulate oil spill weathering process of microbial degradation to investigate compositional changes in a range of source- and weathering-dependent molecular parameters in oil residues, and the conventional diagnostic ratios for oil spill identification were also evaluated. The conventional diagnostic ratios of n-alkane displayed obvious changes after biodegradation, especially for Pr/n-C-17 and Ph/n-C-18 with relative standard deviation more than 118.84 %, which suggests they are invalid for oil source identification of the middle-serious spill. Many polycyclic aromatic hydrocarbons (PAHs) are more resistant to biodegradation process than their saturated hydrocarbon counterparts, thus making PAHs to be one of the most valuable fingerprinting classes of hydrocarbons for oil identification. Biomarker ratios of hopanes and steranes were also useful for source identification even after moderate biodegradation, and the diagnostic ratios from them could be used in tracking origin and sources of hydrocarbon pollution. Finally, the carbon isotopic type curve may provide another diagnostic means for correlation and differentiation of spilled oils, and be particularly valuable for lighter refined products or severely biodegraded oils, the source of which may be difficult to identify by routine biomarker techniques

Construction of a High-Density Genetic Map for Pitaya Using the Whole Genome Resequencing Approach

Pitaya (Hylocereus undatus) is one of the most economic fleshy fruit tree crops. This study aimed at producing a high-density linkage genetic map of pitaya based on the whole genome resequencing (WGrS) approach. For this purpose, a bi-parental F1 population of 198 individuals was generated and genotyped by WGrS. High-quality polymorphic 6434 single polymorphism nucleotide (SNP) markers were extracted and used to construct a high-density linkage map. A total of 11 linkage groups were resolved as expected in accordance with the chromosome number. The map length was 14,128.7 cM with an average SNP interval of 2.2 cM. Homology with the sequenced reference genome was described, and the physical and genetic maps were compared with collinearity analysis. This linkage map in addition to the available genomic resources will help for quantitative trait mapping, evolutionary studies and marker-assisted selection in the important Hylocereus species

Assessment of flight activity and homing ability in Asian and European honey bee species, Apis cerana and Apis mellifera, measured with radio frequency tags

The Asian honey bee Apis cerana and the European honey bee Apis mellifera are closely related and morphologically very similar. Where these species coexist, they appear to compete, but the outcomes of competition vary enormously between locations. Here, we report comparative behavioural data for A. cerana and A. mellifera in China gathered by tracking bees using radio frequency identification. Both species organise their division of labour by temporal polyethism and have remarkably similar demographic structure. Analyses of the homing capacities of both species following large-scale displacement suggest that A. mellifera colonies have a larger range than A. cerana. We observed that relocation of A. mellifera to a new environment disrupted colony function for 3 weeks. Our data show that A. mellifera and. A cerana occupy extremely similar behavioural niches, and therefore, the potential for competition between these species is very high

Assessment of flight activity and homing ability in Asian and European honey bee species, Apis cerana and Apis mellifera, measured with radio frequency tags

The Asian honey bee Apis cerana and the European honey bee Apis mellifera are closely related and morphologically very similar. Where these species coexist, they appear to compete, but the outcomes of competition vary enormously between locations. Here, we report comparative behavioural data for A. cerana and A. mellifera in China gathered by tracking bees using radio frequency identification. Both species organise their division of labour by temporal polyethism and have remarkably similar demographic structure. Analyses of the homing capacities of both species following large-scale displacement suggest that A. mellifera colonies have a larger range than A. cerana. We observed that relocation of A. mellifera to a new environment disrupted colony function for 3 weeks. Our data show that A. mellifera and. A cerana occupy extremely similar behavioural niches, and therefore, the potential for competition between these species is very high.14 page(s

CANCELLED A multiple-continuum approach for modeling multiphase flow in naturall y fractured vuggy petroleum reservoirs

The existence of vugs or cavities in naturally fractured reservoirs has long been observed. Even though these vugs can be largely attributed to reserves of oil, natural gas, and groundwater, few investigations of vuggy fractured reservoirs have been conducted. In this paper, a new multi-continuum conceptual model is developed, based on geological data and observations of core examples from carbonate formations in China, to investigate multiphase flow behavior in such vuggy fractured reservoirs. The conceptual model has been implemented into a three-dimensional, three-phase reservoir simulator with a generalized multi-continuum modeling approach. The conceptual model considers vuggy fractured rock as a triple-continuum medium, consisting of (1) highly permeable fractures, (2) low-permeability rock matrix, and (3) various-sized vugs. The matrix system may contain a large number of small or isolated cavities (of centimeters or millimeters in diameter), whereas vugs are larger cavities, with sizes from centimeters to meters in diameter, indirectly connected to fractures through small fractures or microfractures. Similar to the conventional double-porosity model, the fracture continuum is responsible for the occurrence of global flow, while vuggy and matrix continua, providing storage space, are locally connected to each other (and interacting with globally connecting fractures). For practical application of the multi-continuum concept in reservoir simulation, we propose a novel upscaling method for computing equivalent gridblock permeabilities of coarse blocks containing large isolated vugs, in which the local problems consisting of Darcy and Stokes flows are solved. In addition, we describe an efficient boundary condition for accurate computation of upscaled permeabilities. In the numerical implementation, a control-volume, integral finite-difference method is used for spatial discretization, and a first-order finite-difference scheme is adapted for temporal discretization of governing flow equations in each continuum. The resulting discrete nonlinear equations are solved fully implicitly by Newton iteration. The numerical scheme is verified and applied to simulate water-oil flow through the fractured vuggy reservoirs of Tahe Oil Field in China

CANCELLED A multiple-continuum approach for modeling multiphase flow in naturall y fractured vuggy petroleum reservoirs

The existence of vugs or cavities in naturally fractured reservoirs has long been observed. Even though these vugs can be largely attributed to reserves of oil, natural gas, and groundwater, few investigations of vuggy fractured reservoirs have been conducted. In this paper, a new multi-continuum conceptual model is developed, based on geological data and observations of core examples from carbonate formations in China, to investigate multiphase flow behavior in such vuggy fractured reservoirs. The conceptual model has been implemented into a three-dimensional, three-phase reservoir simulator with a generalized multi-continuum modeling approach. The conceptual model considers vuggy fractured rock as a triple-continuum medium, consisting of (1) highly permeable fractures, (2) low-permeability rock matrix, and (3) various-sized vugs. The matrix system may contain a large number of small or isolated cavities (of centimeters or millimeters in diameter), whereas vugs are larger cavities, with sizes from centimeters to meters in diameter, indirectly connected to fractures through small fractures or microfractures. Similar to the conventional double-porosity model, the fracture continuum is responsible for the occurrence of global flow, while vuggy and matrix continua, providing storage space, are locally connected to each other (and interacting with globally connecting fractures). For practical application of the multi-continuum concept in reservoir simulation, we propose a novel upscaling method for computing equivalent gridblock permeabilities of coarse blocks containing large isolated vugs, in which the local problems consisting of Darcy and Stokes flows are solved. In addition, we describe an efficient boundary condition for accurate computation of upscaled permeabilities. In the numerical implementation, a control-volume, integral finite-difference method is used for spatial discretization, and a first-order finite-difference scheme is adapted for temporal discretization of governing flow equations in each continuum. The resulting discrete nonlinear equations are solved fully implicitly by Newton iteration. The numerical scheme is verified and applied to simulate water-oil flow through the fractured vuggy reservoirs of Tahe Oil Field in China

Expression and functional significance of phosphoenolpyruvate carboxykinase 1 in uveal melanoma

Abstract Uveal melanoma (UVM), an uncommon yet potentially life-threatening ocular cancer, arises from melanocytes in the uveal tract of the eye. The exploration of novel oncotargets for UVM is of paramount importance. In this study, we show that PCK1 (phosphoenolpyruvate carboxykinase 1) expression is upregulated in various UVM tissues as well as in primary UVM cells and immortalized lines. Furthermore, bioinformatics studies reveal that PCK1 overexpression in UVM correlates with advanced disease stages and poor patient survival. Genetic silencing (utilizing viral shRNA) or knockout (via CRISPR/Cas9) of PCK1 significantly curtailed cell viability, proliferation, cell cycle progression, and motility, while provoking apoptosis in primary and immortalized UVM cells. Conversely, ectopic overexpression of PCK1, achieved through a viral construct, bolstered UVM cell proliferation and migration. Gαi3 expression and Akt phosphorylation were reduced following PCK1 silencing or knockout, but increased after PCK1 overexpression in UVM cells. Restoring Akt phosphorylation through a constitutively active mutant Akt1 (S473D) ameliorated the growth inhibition, migration suppression, and apoptosis induced by PCK1 silencing in UVM cells. Additionally, ectopic expression of Gαi3 restored Akt activation and counteracted the anti-UVM cell effects by PCK1 silencing. In vivo, the growth of subcutaneous xenografts of primary human UVM cells was significantly inhibited following intratumoral injection of adeno-associated virus (aav) expressing PCK1 shRNA. PCK1 depletion, Gαi3 downregulation, Akt inhibition, proliferation arrest, and apoptosis were detected in PCK1-silenced UVM xenografts. Collectively, our findings demonstrate that PCK1 promotes UVM cell growth possibly by modulating the Gαi3-Akt signaling pathway

Lateralization of gene expression in the honeybee brain during olfactory learning

In the last decade, it has been demonstrated that brain functional asymmetry occurs not only in vertebrates but also in invertebrates. However, the mechanisms underlying functional asymmetry remain unclear. In the present study, we trained honeybees of the same parentage and age, on the proboscis extension reflex (PER) paradigm with only one antenna in use. The comparisons of gene expression between the left and right hemispheres were carried out using high throughput sequencing. Our research revealed that gene expression in the honeybee brain is also asymmetric, with more genes having higher expression in the right hemisphere than the left hemisphere. Our studies show that during olfactory learning, the left hemisphere is more responsible for long term memory and the right hemisphere is more responsible for the learning and short term memory.This work was supported by Chinese Academy of Science Strategic Project of Leading Science and Technology (XDA01020402), the National High Technology Research and Development Program (“863” Program) of China (2012AA020402 and 2012AA02A202), the Earmarked Fund for China Agriculture Research System (No. CARS‐45‐KXJ12), the National Natural Science Foundation of China (No. 31260524) and the Research Fund for the Doctoral Program of Higher Education of China (No. 20123603120005)

Decoupled Ionic and Electronic Pathways for Enhanced Osmotic Energy Harvesting

Methods of reducing nanofluids’ internal resistance by mixing conductive nanomaterials will negatively affect the nanochannel structures and ion transmissions. Herein, a layered-structured nanofluidic membrane that achieves ion transport in the internal cellulose nanochannels and realizes electron transport in the external polyaniline network is developed. Results show that the ionic conductivity and resistivity of the layered membrane at low salt concentrations are 1.57 times higher and 0.99 times lower than those of the blend membrane, demonstrating the positive contribution of decoupled ionic and electronic pathways. Furthermore, the layered membrane attained an enhanced output power density of 11.7 W m–2 and maintained an output performance of up to 10.9 W m–2 after 16 days of operation under the neutral 50-fold salinity concentration gradient, which is higher than that of the commercial system (5.0 W m–2). Overall, this research expands the materials for osmotic energy–harvesting systems based on the design of ion and electron decoupling paths in biomass materials