bluuebunny/crossref_metadata_2025 huggingface dataset:
School nutritional capacity, resources and practices are associated with availability of food/beverage items in schools
Authors: Mâsse Louise C , de Niet Judith E
Published: February 2013

Background

The school food environment is important to target as less healthful food and beverages are widely available at schools. This study examined whether the availability of specific food/beverage items was associated with a number of school environmental factors.

Methods

Principals from elementary (n = 369) and middle/high schools (n = 118) in British Columbia (BC), Canada completed a survey measuring characteristics of the school environment. Our measurement framework integrated constructs from the Theories of Organizational Change and elements from Stillman’s Tobacco Policy Framework adapted for obesity prevention. Our measurement framework included assessment of policy institutionalization of nutritional guidelines at the district and school levels, climate, nutritional capacity and resources (nutritional resources and participation in nutritional programs), nutritional practices, and school community support for enacting stricter nutritional guidelines. We used hierarchical mixed-effects logistic regression analyses to examine associations with the availability of fruit, vegetables, pizza/hamburgers/hot dogs, chocolate candy, sugar-sweetened beverages, and french fried potatoes.

Results

In elementary schools, fruit and vegetable availability was more likely among schools that have more nutritional resources (OR = 6.74 and 5.23, respectively). In addition, fruit availability in elementary schools was highest in schools that participated in the BC School Fruit and Vegetable Nutritional Program and the BC Milk program (OR = 4.54 and OR = 3.05, respectively). In middle/high schools, having more nutritional resources was associated with vegetable availability only (OR = 5.78). Finally, middle/high schools that have healthier nutritional practices (i.e., which align with upcoming provincial/state guidelines) were less likely to have the following food/beverage items available at school: chocolate candy (OR = .80) and sugar-sweetened beverages (OR = .76).

Conclusions

School nutritional capacity, resources, and practices were associated with the availability of specific food/beverage items in BC public schools. Policies targeting the school environment are increasingly being considered as one of the strategies used to address childhood obesity, as a result it is important to further understand the factors associated with the availability of specific food/beverage items at school.
Annealing effect on Sb2S3-TiO2 nanostructures for solar cell applications
Authors: Li Yitan , Wei Lin , Zhang Ruizi , Chen Yanxue , Mei Liangmo , Jiao Jun
Published: February 2013

Nanostructures composited of vertical rutile TiO2 nanorod arrays and Sb2S3 nanoparticles were prepared on an F:SnO2 conductive glass by hydrothermal method and successive ionic layer adsorption and reaction method at low temperature. Sb2S3-sensitized TiO2 nanorod solar cells were assembled using the Sb2S3-TiO2 nanostructure as the photoanode and a polysulfide solution as an electrolyte. Annealing effects on the optical and photovoltaic properties of Sb2S3-TiO2 nanostructure were studied systematically. As the annealing temperatures increased, a regular red shift of the bandgap of Sb2S3 nanoparticles was observed, where the bandgap decreased from 2.25 to 1.73 eV. At the same time, the photovoltaic conversion efficiency for the nanostructured solar cells increased from 0.46% up to 1.47% as a consequence of the annealing effect. This improvement can be explained by considering the changes in the morphology, the crystalline quality, and the optical properties caused by the annealing treatment.
Two types of permanence of a stochastic mutualism model
Authors: Qiu Hong , Lv Jingliang , Wang Ke
Published: February 2013

A stochastic mutualism model is proposed and investigated in this paper. We show that there is a unique solution to the model for any positive initial value. Moreover, we show that the solution is stochastically bounded, uniformly continuous and globally attractive. Under some conditions, we conclude that the stochastic model is stochastically permanent and persistent in mean. Finally, we introduce some figures to illustrate our main results.
Age matters:  Young T lymphocytes offer better protection from myeloma proliferation
Authors: Glick Alexander F , Song Yan S , Hwang Brian , Lillvis John , Zanzonico Pat , Fuchs Camil , Pearse Roger N , Szabo Paul , Weksler Marc E
Published: February 2013

Background

The incidence and growth of cancer has been reported to increase with age and/or impaired T lymphocyte function.

Results

Consistent with these observations, we found that a monoclonal serum immunoglobulin (mIgG2b), rarely detectable after the injection of 5T33 murine multiple myeloma (MMM) cells into 3–4 month old wild-type C57BL/6 mice was seen more frequently in 18–20 month old wild-type C57BL/6 mice and in 3–4 month old Rag1-deficient C57BL/6 mice. These observations were confirmed and extended using more sensitive assays such as quantitation of splenic mRNA specific for the canonical 5T33 monoclonal IgG2b produced by 5T33 myeloma cells and the most sensitive assay, photon-imaging of mice injected with 5T33 cells, stably transfected with fire-fly luciferase gene (5T33L cells), which emit photons after the injection of luciferin. Furthermore, the proliferation of 5T33L myeloma cells in Rag1-deficient C57BL/6 mice was greater in mice which also received spleen T cells from 18–20 month old C57BL/6 wild-type mice compared to mice which received splenic T cells from 3–4 month old C57BL/6 wild-type mice. Thus, immune reconstitution of C57BL/6 mice with splenic T cells from young wild-type mice offered greater protection from progressive growth of 5T33L myeloma cells than did reconstitution with splenic T cells from old mice.

Conclusions

Our findings support the hypothesis that age-associated changes in splenic T cell function contribute to the increased growth of 5T33 MMM cells in old compared to young C57BL/6 mice. Should similar processes occur in humans, increasing the anti-myeloma activity of T cells in old patients with multiple myeloma or transferring cryopreserved, young, autologous, T cells might benefit elderly patients with multiple myeloma.
A novel highly thermostable xylanase stimulated by Ca2+ from Thermotoga thermarum: cloning, expression and characterization
Authors: Shi Hao , Zhang Yu , Li Xun , Huang Yingjuan , Wang Liangliang , Wang Ye , Ding Huaihai , Wang Fei
Published: February 2013

Background

Xylanase is an important component of hemicellulase enzyme system. Since it plays an important role in the hydrolysis of hemicellulose into xylooligosaccharides (XOs), high thermostable xylanase has been the focus of much recent attention as powerful enzyme as well as in the field of biomass utilization.

Results

A xylanase gene (xyn10A) with 3,474 bp was cloned from the extremely thermophilic bacterium Thermotoga thermarum that encodes a protein containing 1,158 amino acid residues. Based on amino acid sequence homology, hydrophobic cluster and three dimensional structure analyses, it was attested that the xylanase belongs to the glycoside hydrolase (GH) families 10 with five carbohydrate binding domains. When the xylanase gene was cloned and expressed in Escherichia coli BL21 (DE3), the specific enzyme activity of xylanase produced by the recombinant strain was up to 145.8 U mg-1. The xylanase was optimally active at 95°C, pH 7.0. In addition, it exhibited high thermostability over broad range of pH 4.0-8.5 and temperature 55-90°C upon the addition of 5 mM Ca2+. Confirmed by Ion Chromatography System (ICS) analysis, the end products of the hydrolysis of beechwood xylan were xylose, xylobiose, xylotriose, xylotetraose, xylopentaose and xylohexaose.

Conclusions

The xylanase from T. thermarum is one of the hyperthermophilic xylanases that exhibits high thermostability, and thus, is a suitable candidate for generating XOs from cellulosic materials such as agricultural and forestry residues for the uses as prebiotics and precursors for further preparation of furfural and other chemicals.
Assessment of disease control in allergic rhinitis
Authors: Demoly Pascal , Calderon Moises A , Casale Thomas , Scadding Glenis , Annesi‐Maesano Isabella , Braun Jean‐Jacques , Delaisi Bertrand , Haddad Thierry , Malard Olivier , Trébuchon Florence , Serrano Elie
Published: February 2013

The Allergic Rhinitis and its Impact on Asthma (ARIA) initiative has had a significant impact, by raising awareness of allergic rhinitis (AR) and improving the diagnosis and treatment of AR sufferers. ARIA classifies the severity of AR as “mild” or “moderate/severe” on the basis of “yes”/“no” answers to four questions. This two‐point classification has been criticized as providing little guidance on patient management; patients with “mild” AR are unlikely to consult a physician, whereas the group of patients with “moderate/severe” seen by specialists is heterogeneous. These perceived shortcomings have prompted attempts to improve the ARIA classification or, by analogy with the Global Initiative for Asthma (GINA), adopt approaches based on “disease control” in AR. Even though “disease severity”, “disease control” and “responsiveness to treatment” are different (albeit related) metrics, they are not mutually exclusive. Currently, there is no single, accepted definition, but we propose that “disease control” in AR can combine (i) measurements of the severity and/or frequency of daily or nocturnal symptoms, (ii) impairments in social, physical, professional and educational activities, (iii) respiratory function monitoring and (iv) exacerbations (e.g. unscheduled medical consultations and rescue medication use). Although control‐based classifications have a number of limitations (e.g. their dependence on treatment compliance and the patient's psychological status), these instruments could be used as an adjunct to the ARIA severity classification and regional practice parameters. Here, we assess the strengths and weaknesses of the current two‐level ARIA classification, analyze published proposals for its modification and review the literature on instruments that measure AR control. We conclude that there is a need for research in which severity is compared with control in terms of their effects on patient management.
Poplitealer Reflux bei Insuffizienz der Vena saphena parva
Authors: Mendoza E.
Published: February 2013

Einleitung: Insuffiziente Stammvenen füllen sich in der Regel über ihre Mündung aus der tiefen Beinvene. Bei Reflux in der V. saphena parva beobachtet man dabei ebenso einen Reflux in der V. poplitea, aus der sich die V. saphena parva in der muskulären Diastole füllt.

Fallbeispiel: Bei einer Patientin wurde der Fluss in der refluxiven V. saphena parva vor und nach Unterbrechung eines Seitenastes nach CHIVA mit dem Ergebnis der Flussumkehr im Saphena-Stamm mit Duplex dargestellt.

Ergebnis: Unmittelbar nach Ligatur des Seitenastes stellt sich in der V. saphena parva eine Flussumkehr ein mit orthogradem Fluss. Ebenso in der V. poplitea, in der postoperativ kein Reflux mehr zu finden ist.

Conclusio: Die V. poplitea ist das Reservoire, aus dem sich die insuffiziente V. saphena parva füllt, daher ist proximal der Mündung der V. saphena parva in der V. poplitea ein Reflux darstellbar – und nach Korrektur der Insuffizienz der V. saphena parva ist dieser nicht mehr nachweisbar.
A possible quantitative Mueller matrix transformation technique for anisotropic scattering media/Eine mögliche quantitative Müller-Matrix-Transformations-Technik für anisotrope streuende Medien
Authors: He Honghui , Zeng Nan , Du E , Guo Yihong , Li Dongzhi , Liao Ran , Ma Hui
Published: February 2013

By conducting both the experiments on samples containing well-aligned fibers and Monte Carlo simulations based on the sphere cylinder scattering model (SCSM), we present a Mueller matrix transformation (MMT) method for quantitatively characterizing the properties of anisotropic scattering media. We obtained a set of parameters by fitting the Mueller matrix elements to trigonometric curves in polar coordinates. These new parameters can be expressed as analytical functions of the Mueller matrix elements and display simple relationships to the structural and optical properties of the anisotropic scattering media, such as the anisotropy, the direction of the fibers, and the sizes of the scatterers. Experimental results on biological tissues show that these new parameters can be used in biomedical research. However, further studies are still necessary to correlate the MMT parameters to pathological features.
Influence of Lightweight Deflectometer Characteristics on Deflection Measurement
Authors: Stamp David H. , Mooney Michael A.
Published: February 2013

The lightweight deflectometer (LWD) is currently not standardized; as a result, there are a number of commercially available LWD designs that yield different deflection and elastic modulus values. This proves problematic because transportation agencies are beginning to prescribe target deflections and/or elastic modulus values during earthwork construction. This paper presents the results of a comprehensive investigation into the influence of LWD design characteristics on measured deflection. The influence of the sensor type (accelerometer versus geophone), sensing configuration (measurement of plate versus ground surface), LWD rigidity, and applied load pulse were investigated through field testing and finite element analysis. The investigation revealed that the sensing configuration (i.e., the measurement of plate versus ground surface response) is the predominant cause of differences between the Zorn and Prima LWD responses (deflection normalized by peak force). Vertical plate deflection exceeded ground surface deflection by 65 % to 310 % on soils and by 20 % on asphalt. The relative influences of the sensor type (accelerometer versus geophone), plate rigidity, and load pulse each led to relatively small differences (<10 %) between Zorn and Prima LWD responses. The results of this investigation illustrate that each of the two LWD configurations will always produce different deflection and elastic modulus values for the same ground conditions, and that the differences will be difficult to predict.
Crystal structure of phosphido-tris-(triphenylphosphine)copper(I)acetone solvate, C57H51CuOP4
Authors: Hill Tania N.
Published: February 2013

C57H51CuOP4, triclinic, P1̄ (no. 2), a = 11.2814(8) Å, b = 13.585(1) Å, c = 15.666(1) Å, α = 88.785(4)°, β = 84.288(3)°, γ = 85.103(3)°, V = 2380.1 Å3, Z = 2, Rgt(F) = 0.0444, wRref(F2) = 0.1159, T = 100 K.
Ab-initio structure determination of novel strontium-containing layered silicate AES-18 synthesized using mechanochemical reaction
Authors: Ikeda Takuji , Ideta Chiaki , Yamamoto Katsutoshi
Published: February 2013

A new strontium-containing layered silicate, alkaline earth-containing silicate (AES)-18 [chemical composition: Si16O24(OH)16 · {Sr(OH)2}8 · (KOH)2], was synthesized utilizing a mechanochemical reaction in which an admixture of strontium hydroxide, which unfavorably precipitates in conventional syntheses, and a fumed silica (Aerosil) was allowed to react in the solid phase. The crystal structure of AES-18 was elucidated by the charge-flipping method using powder X-ray diffraction data, and the obtained structure was refined by a combination with the Rietveld method and the maximum entropy method (MEM). The structure analyses showed a tetragonal symmetry with a = 0.912738(3) nm, c = 1.628120(8) nm, and the space group P42/mnc. Two silicate layers composed of Q3 local structure [(—SiO)3Si—OH], 7-coordinated Sr2+ catäions, and K+ cations were included in a unit cell, and a Sr4(OH)17 cluster was formed between adjacent silicate layers. The framework topology of AES-18 containing 4- and 8-Si-membered rings was similar to that of paracelsian.
RAB13 regulates Sertoli cell permeability barrier dynamics through protein kinase A
Authors: Su Wenhui , Liu Xinchun
Published: February 2013

In mammalian testes, the blood–testis barrier (BTB), created by specialized junctions between Sertoli cells near the basement membrane of the seminiferous epithelium, provides an indispensable immune-privileged microenvironment for spermatid development. However, the BTB must experience restructuring during the epithelial cycle to facilitate the transit of preleptotene spermatocytes upon the testosterone-induced new TJ fibrils forming behind these cells, which is intimately related to the extensive dynamics of junction protein complexes between Sertoli cells. As key regulators of protein traffic, Rab GTPases participate in delivery of proteins between distinct cellular sites and cross talk with proteins that constitute tight junction and adherens junction. Using primarily cultured Sertoli cellsin vitrowith an established tight junction permeability barrier that mimics the BTBin vivo, RAB13 was shown to decrease during the testosterone-induced TJ integrity enhancement, accompanied with an increment in protein kinase A (PKA) activity. Furthermore, knockdown ofRab13was found to resemble the effect of testosterone on Sertoli cell TJ permeability by reinforcing filamentous actin and occludin distribution at the cell–cell interface and promoting the direct interaction between ZO-1 and occludin. Interestingly, the effects of testosterone andRab13knockdown on Sertoli cell epithelium were revealed to be antagonized by PKA activity inhibition. In summary, RAB13 serves as a regulatory component in the assembly and restructuring of the TJ fibrils between adjacent Sertoli cells.
Investigation of biocompatibility on nitrogen-doped a-C:H film coating scaffold surface in in-vivo and in-vitro tests
Authors: Ohgoe Yasuharu , Wada Tomoaki , Shiraishi Yasuyuki , Miura Hidekazu , Hirakuri Kenji K. , Funakubo Akio , Yambe Tomoyuki , Fukui Yasuhiro
Published: February 2013

In this study, in order to investigate biocompatibility of nitrogen-doped hydrogenated amorphous carbon (a-C:H:N) film coating segmented polyurethane (SPU) scaffold fiber sheet (a-C:H:N-Scaffold) in in-vitro test, mouse fibroblasts (NIH 3T3) cells were grown on the a-C:H:N-Scaffold. The cell behavior was monitored by time-lapse imaging system. Additionally, the a-C:H:N-Scaffold was implanted at partial aorta descendens of a goat for 35 days. The surface morphology, composition, and wettability of the a-C:H:N-scaffold was estimated by Scanning Electron Microscope (SEM), X-ray photoelectron spectrometer (XPS), and contact angle measurement. In in-vitro test, it was observed that a-C:H:N film coating had a facilitatory effect on cell motility and cell growth. In in-vivo test, it was observed that the a-C:H:N-Scaffold surface was uniformly covered by neointima. The a-C:H:N-Scaffold surface had no thrombus formation as an inflammatory reaction and it was shown that the a-C:H:N film coating had a good blood compatibility. These results suggest that a-C:H:N film coating has good cytocompatibility and blood compatibility and it is a promising approach for improvement of biocompatibility of biomaterial surfaces.
Crystal Structure of Non-Doped and Sn-Doped α-(GaFe)2O3Thin Films.
Authors: Kaneko Kentaro , Akaiwa Kazuaki , Fujita Shizuo
Published: February 2013

Corundum structured α-(GaFe)2O3alloy thin films were obtained on c-plane sapphire substrates by the mist chemical vapor deposition method. Wide range of X-ray diffraction 2θ/θ scanning measurements indicated that these crystals were epitaxially grown on c-plane sapphire substrates and these are no other crystal oriented phase. The cross-sectional and plane-view transmission electron microscope images showed the growth along the c-axis of α-(GaFe)2O3thin films on sapphire substrates, forming joint of columnar structure. The non-doped α-(GaFe)2O3thin films showed ferromagnetic properties at 300 K, though the origin of ferromagnetism still remained unresolved. In order to enhance the spin-carrier interaction, Sn doped α-(GaFe)2O3alloy thin films were fabricated on c-plane sapphire substrates. X-ray diffraction 2θ/θ and ω scanning measurement results indicated that the highly-crystalline films were epitaxially grown on substrates in spite of the Sn-doping.
A Review of the Role of Excess si in SIO2 at the Growing Oxide Interface.
Authors: Jaccodine Ralph
Published: February 2013

This paper discusses the issues that arise when ab excess of Si or SiO flux is used to adjust the Deal -Grove model to match the observed growth in the early stages of oxidation. The author uses the insight gained from the modeling of the oxidation of Si-Ge alloys as a background to the discussion. A recent simulation of the thin oxide problem by M. Uematsu et.al. invokes the role of “excess Si” near the interface to adjust the D&G reaction coefficient and also add additional flux to the growing oxide.This paper assesses some of the points in this model as well as the relation with sub bonded Si and/or the reaction barrier layer to oxidationmechanism. A recent proposal by Pasquarello et.al opens new insight into the way the interface may adjust to the growing oxide which challenges our previous mechanistic notions.
A Critical Assessment of Several Reservoir Simulators for Modeling Chemical Enhanced Oil Recovery Processes
Authors: Goudarzi Ali , Delshad Mojdeh , Sepehrnoori Kamy
Published: February 2013

Interest in chemical enhanced oil recovery (CEOR) processes has intensified in recent years because of rising oil prices as well as the advancement in chemical formulations and injection techniques. Polymer (P), surfactant/polymer (SP), and alkaline/surfactant/polymer (ASP) are techniques for improving sweep and displacement efficiencies with the aim of improving oil production in both secondary and tertiary floods. Chemical flooding has much broader range of applicability than the past. These include high temperature reservoirs, formations with extreme salinity and hardness, naturally fractured carbonates, and sandstone reservoirs with heavy and viscous crude oils.

More oil reservoirs are reaching maturity where secondary polymer floods and tertiary surfactant methods have become increasingly important. This significance has added to the industry's interest in using reservoir simulator as a tool for reservoir evaluation and management to minimize costs and increase the process efficiency. Reservoir simulators with special features are needed to represent coupled chemical and physical processes present in CEOR processes. The simulators need to be first validated against well controlled lab and pilot scale experiments to have reliable predictions of the full field implementations.

The available data from laboratory scale include 1) phase behavior and rheological data, 2) results of secondary and tertiary coreflood experiments for P, SP, and ASP floods under reservoir conditions, i.e. chemical retentions, pressure drop, and oil recovery. Data collected from corefloods are used as benchmark tests comparing numerical reservoir simulators with CEOR modeling capabilities such as STARS of CMG, ECLIPSE-100 of Schlumberger, REVEAL of Petroleum Experts, and UTCHEM from The University of Texas at Austin. The research UTCHEM simulator is included since it has been the benchmark for chemical flooding simulation for over 25 years.

The results of this benchmark comparison will be utilized to improve chemical design for field-scale studies using commercial simulators. The benchmark tests illustrate the potential of commercial simulators for chemical flooding projects and provide a comprehensive table of strength and limitation of each simulator for a given CEOR process. Mechanistic simulations of chemical EOR processes will provide predictive capability and can aid in optimization of the field injection projects. The objective of this paper is not to compare the computational efficiency and solution algorithms and only focus on the process modeling comparison.
An Ensemble Based Nonlinear Orthogonal Matching Pursuit Algorithm for Sparse History Matching of Reservoir Models
Authors: Elsheikh Ahmed H. , Wheeler Mary F. , Hoteit Ibrahim
Published: February 2013

A nonlinear orthogonal matching pursuit (NOMP) for sparse calibration of reservoir models is presented. Sparse calibration is a challenging problem as the unknowns are both the non-zero components of the solution and their associated weights. NOMP is a greedy algorithm that discovers at each iteration the most correlated components of the basis functions with the residual. The discovered basis (aka support) is augmented across the nonlinear iterations. Once the basis functions are selected from the dictionary, the solution is obtained by applying Tikhonov regularization. The proposed algorithm relies on approximate gradient estimation using an iterative stochastic ensemble method (ISEM). ISEM utilizes an ensemble of directional derivatives to efficiently approximate gradients. In the current study, the search space is parameterized using an overcomplete dictionary of basis functions built using the K-SVD algorithm.
Multiscale Simulation of CHOPS Wormhole Networks
Authors: Vanderheyden Brian , Jayaraman Balaji , Ma Xia , Zhang Duan
Published: February 2013

Cold Heavy Oil Production with Sand (CHOPS) is a well-known primary heavy oil recovery method. In CHOPS, a key mechanism of production is the formation of wormholes. Wormholes are believed to be nearly cylindrical zones of high permeability that originate from production wells when sand is produced along with the oil. A multi-scale modelling approach based on the multiphase material point method (MMPM) has been applied to the problem of developing a general predictive capability for CHOPS and wormhole growth. The MMPM is a Lagrangian-Eulerian methodology which permits simulation of multiphase flow problems with fluid-structure interaction in which there is substantial material deformation, damage and failure. MMPM is applied to the problem of simulating the growth of a wormhole in unconsolidated sand with live oil including the effect of foamy oil and sand failure. The simulation results show general features such as asymmetry and slugging. Comparison with experimental data for wormhole length with time was favourable. Up-scaling of the method is required to make predictions on the well to field scale. For this purpose, an up-scaled pressure-field-driven scheme has been developed to predict wormhole network structure. It is hypothesized that a pressure-field-based approached is adequate for a macroscopic simulation with resolution above the length scale of the wormhole tips at which the tensor nature of the failure mechanics are more important. The model includes a generalized sand failure criterion that couples with a non-linear pressure equation and foamy oil and sand flow equations. The model resolves separate wormhole regions emerging from the CHOPS pilot well. Robust history matching of commercial pilot production data is provided as partial model validation.
Nonlinear Complexity Reduction for Fast Simulation of Flow in Heterogeneous Porous Media
Authors: Gildin Eduardo , Ghasemi Mohammadreza , Romanovskay Anastasiya , Efendiev Yalchin
Published: February 2013

Reduced order modeling techniques have been investigated in the context of reservoir simulation and optimization in the past decade in order to mitigate the computational cost associated with the large-scale nature of the reservoir models. Although great progress has been made in basically two fronts, namely, upscaling and model reduction, there has not been a consensus which method (or methods) is preferable in terms of the trade-offs between accuracy and robustness, and if they indeed, result in large computational savings. In the particular case of model reduction, such as the proper orthogonal decomposition (POD), in order to capture the nonlinear behavior of such models, many simulations or experiments are needed prior to the actual online computations and there in not a clear way to deal with the projection of the reduced basis onto the nonlinear terms for fast implementations.

This paper presents a step forward to reduced-order modeling in the reservoir simulation framework. In order to overcome the issues with the nonlinear projections, we proposed to use the POD-DEIM algorithm, based on POD combined with the discrete em- pirical interpolation method (DEIM) proposed for the solution of large-scale partial differential equations. The DEIM is based on the approximation of the nonlinear terms by means of an interpolatory projection of few selected snapshots of the nonlinear terms. In this case, computational savings can be obtained in a forward run of nonlinear models.

Also, in order to incorporate information from the multiple length of scales, especially in the case of highly heterogeneous porous media, we suggest the local-global model reduction framework using the multiscale modeling framework. In this case, we will extend the use of the balanced truncation formulation and show how to couple both frameworks.
Beyond Dual-Porosity Modeling for the Simulation of Complex Flow Mechanisms in Shale Reservoirs
Authors: Yan Bicheng , Wang Yuhe , Killough John E.
Published: February 2013

The state of the art of modeling fluid flow in shale reservoirs is dominated by dual porosity models which divide the reservoirs into matrix blocks that significantly contribute to fluid storage and fracture networks which principally control flow capacity. However, recent extensive microscopic studies reveal that there exist massive micro- and nano-pore systems in shale matrices. Because of this, the actual flow mechanisms in shale reservoirs are considerably more complex than can be simulated by the conventional dual porosity models and Darcy’s Law. Therefore, a model capturing multiple pore scales and flow can provide a better understanding of complex flow mechanisms occurring in these reservoirs.

Through the use of a unique simulator this paper presents a micro-scale multiple-porosity model for fluid flow in shale reservoirs by capturing the dynamics occurring in three separate porosity systems: organic matter (mainly kerogen), inorganic matter, natural fractures. Inorganic and organic portions of shale matrix are treated as sub-blocks with different attributes, such as wettability and pore structures. In the organic matter or kerogen, gas desorption and diffusion are the dominant physics. Since the flow regimes are sensitive to pore size, the effects of nanopores and vugs in kerogen are incorporated into the simulator. The separate inorganic sub-blocks mainly contribute to the ability to better model dynamic water behavior. The multiple porosity model is built upon a unique tool for simulating general multiple porosity systems in which several porosity systems may be tied to each other through arbitrary transfer functions and connectivities. This new model allows us to better understand complex flow mechanisms and in turn is extended into the reservoir scale considering hydraulic fractures through upscaling techniques. Sensitivity studies on the contributions of the different flow mechanisms and kerogen properties give some insight as to their importance. Results also include a comparison of the conventional dual porosity treatment and show that significant differences in fluid distributions and dynamics are obtained with the improved multiple porosity simulation. Finally a case for reservoir-scale model covering organic matter, inorganic matter, natural fractures and hydraulic fractures is presented and will allow operators to better predict ultimate recovery from shale reservoirs.
A New Lattice Boltzmann Equation to Simulate Density-Driven Convection of Carbon Dioxide
Authors: Allen Rebecca , Reis Tim , Sun Shuyu
Published: February 2013

The storage of CO2 in fluid-filled geological formations has been carried out for more than a decade in locations around the world. After CO2 has been injected into the aquifer and has moved laterally under the aquifer’s cap-rock, density-driven convection becomes an important transport process to model. However, the challenge lies in simulating this transport process accurately with high spatial resolution and low CPU cost. This issue can be addressed by using the lattice Boltzmann equation (LBE) to formulate a model for a similar scenario when a solute diffuses into a fluid and density differences lead to convective mixing. The LBE is a promising alternative to the traditional methods of computational fluid dynamics. Rather than discretizing the system of partial differential equations of classical continuum mechanics directly, the LBE is derived from a velocity-space truncation of the Boltzmann equation of classical kinetic theory.

We propose an extension to the LBE, which can accurately predict the transport of dissolved CO2 in water, as a step towards fluid-filled porous media simulations. This is achieved by coupling two LBEs, one for the fluid flow and one for the convection and diffusion of CO2. Unlike existing lattice Boltzmann equations for porous media flow, our model is derived from a system of moment equations and a Crank-Nicolson discretization of the velocity-truncated Boltzmann equation. The forcing terms are updated locally without the need for additional central difference approximation. Therefore our model preserves all the computational advantages of the single-phase lattice Boltzmann equation and is formally second-order accurate in both space and time. Our new model also features a novel implementation of boundary conditions, which is simple to implement and does not suffer from the grid-dependent error that is present in the standard "bounce-back" condition.

The significance of using the LBE in this work lies in the ability to efficiently simulate density-driven convection of CO2 through water. From an implementation viewpoint, the locality of our algorithm exploits massively parallel modern computer architectures, including graphics processing units (GPUs), which would lead to very fast computations that scale linearly with the number of processors.
Efficient Markov Chain Monte Carlo Sampling Using Polynomial Chaos Expansion
Authors: Bazargan Hamid , Christie Mike , Tchelepi Hamdi
Published: February 2013

Markov Chain Monte Carlo (MCMC) methods are often used to probe the posterior probability distribution in inverse problems. This allows for computation of estimates of uncertain system responses conditioned on given observation data by means of approximate integration. However, these methods suffer from the computational complexities in reservoir simulation. It is hence of great interest to propose a sparse approximation technique to represent the posterior probability density function and conditional expectations given the data.

Polynomial Chaos Expansion (PCE) is a powerful tool to quantify uncertainty in dynamical systems when there is probabilistic uncertainty in the system parameters. In reservoir simulation it has been shown to be more accurate and efficient compared with traditional experimental design (ED). PCEs have a significant advantage over other response surfaces as the convergence to the true probability distribution when the order of the PCE is increased can be proved. PCEs as applied with Non-Intrusive Spectral Projection (NISP) to compute the coefficients, have successfully and efficiently approximated the distribution of output random variables of interest such as cumulative oil production. Accordingly polynomial chaos proxy can be used as the pseudo-simulator to represent the probability density function of the uncertain variables.

We propose the application of polynomial chaos proxy as applied with the MCMC method to efficiently sample from the posterior probability density function of the system parameters. We present a two dimensional example of fluvial channels to demonstrate that with a few hundred trial runs of the actual reservoir simulator, it is feasible to construct a polynomial chaos proxy which accurately approximates the posterior distribution of the high permeability zones, in an analytical form. We show that precision improves as the order of PCE and the number of trial runs used to calculate the PCE coefficients is increased. Then we use Markov Chain Monte Carlo methods to sample from this sparse analytical representation of the posterior distribution.
Laboratory-scale anaerobic sequencing batch reactor for treatment of stillage from fruit distillation
Authors: Rada Elena Cristina , Ragazzi Marco , Torretta Vincenzo
Published: February 2013

This work describes batch anaerobic digestion tests carried out on stillages, the residue of the distillation process on fruit, in order to contribute to the setting of design parameters for a planned plant. The experimental apparatus was characterized by three reactors, each with a useful volume of 5 L. The different phases of the work carried out were: determining the basic components of the chemical oxygen demand (COD) of the stillages; determining the specific production of biogas; and estimating the rapidly biodegradable COD contained in the stillages. In particular, the main goal of the anaerobic digestion tests on stillages was to measure the parameters of specific gas production (SGP) and gas production rate (GPR) in reactors in which stillages were being digested using ASBR (anaerobic sequencing batch reactor) technology. Runs were developed with increasing concentrations of the feed. The optimal loads for obtaining the maximum SGP and GPR values were 8–9 gCOD L−1 and 0.9 gCOD g−1 volatile solids.
Adsorptive removal of phosphate from aqueous solutions using lead–zinc tailings
Authors: Wang Shuncai , Yuan Rongzhuo , Yu Xueyong , Mao Chaojie
Published: February 2013

This study explored the feasibility of utilizing lead–zinc tailings for phosphate removal in laboratory experiments. The adsorption isotherm, kinetics and pH effect were examined in batch experiments. The Freundlich and Langmuir isotherm models were used for data fitting. The adsorption kinetics can be best described by the simple Elovich equation. The phosphate adsorption tends to decrease with the increase of pH, from 0.37 mg P/g at pH 2.05 to 0.12 mg P/g at pH 7.01, and tends to increase from 0.12 mg P/g at pH 7.01 to 0.64 mg P/g at pH 12.52. The actual phosphate removal on the tailings could be a consequence of adsorption and precipitation reactions with Fe, Al and Ca. Due to their low cost, this type of tailings has the potential to be utilized for cost-effective removal of phosphate from wastewater.
Prediction of chlorophyll-a in the Daning River of Three Gorges Reservoir by principal component scores in multiple linear regression models
Authors: Liping Wang , Binghui Zheng
Published: February 2013

After the impoundment of the Three Gorges Reservoir (TGR) since 2003, eutrophication has occurred and has become severe in Daning River. To predict chlorophyll-a (Chl-a) levels, the relationships between Chl-a and 11/13 routine monitoring data on water quality and hydrodynamics in Daning River were studied by principal component scores in the multiple linear regression model (principal component regression (PCR) model). In order to determine the hydrodynamic effect on simulated accuracy, two 0-day ahead prediction models were established: model A without hydrodynamic factors as variables, and model B with hydrodynamic factors (surface water velocity and water residence time) as variables. Based on the results of correlation analysis, score 1 and 2 with significant loads of phosphorus and nitrogen nutrients were omitted in developing model A (R2 = 0.355); while score 2 with significant loads of nitrogen was omitted in developing model B (R2 = 0.777). The results of validation using a new dataset showed that model B achieved a better fitted relationship between the predicted and observed values of Chl-a. It indicated hydrodynamics play an important role in limiting algal growth. The results suggested that a PCR model incorporating hydrodynamics processes has been suitable for the Chl-a concentration simulation and algal blooming prediction in Daning River of TGR.
Population genetic characteristics of horse chestnut in Serbia
Authors: Ocokoljic Mirjana , Vilotic Dragica , Sijacic-Nikolic Mirjana
Published: February 2013

The general population genetic characteristics of cultivated horse chestnut
trees excelling in growth, phenotype characteristics, type of inflorescence,
productivity and resistance to the leafminer Cameraria ohridella Deschka and
Dimic were analyzed in Serbia. The analyzed population genetic parameters
point to fundamental differences in the genetic structure among the
cultivated populations in Serbia. The study shows the variability in all
properties among the populations and inter-individual variability within the
populations. The variability and differential characteristics were assessed
using statistical parameters, taking into account the satisfactory reflection
of the hereditary potential. The assessed differences in the vitality and
evolution potential of different populations can determine the methods of
horse chestnut gene pool collection, reconstruction and improvement.
Brain cortical injury induces changes in peripheral lymphocyte ectonucleotidase activities
Authors: Laketa Danijela , Bjelobaba Ivana , Stojkov Danijela , Lavrnja Irena , Parabucki Ana , Stojiljkovic Mirjana , Nedeljkovic Nadezda
Published: February 2013

Injury and other pathological conditions induce a massive release of ATP and
ADP that initiate an immune response. Extracellular nucleotides are degraded
by ectonucleotidases: enzymes from E-NTPDase and E-NPP families sequentially
hydrolyze ATP and ADP to AMP, which is further hydrolyzed by
ecto-5?-nucleotidase to adenosine that exerts suppressive effects on immune
cells. We investigated the ectonucleotidase activities of peripheral
lymphocytes at different post-injury times after an unilateral brain injury
in the rat. Significant and dynamic changes in the lymphocytic
ectonucleotidase activities were obtained. ATP- and ADP-hydrolysis changes,
together with their calculated ratios, indicate the major contribution of
E-NTPDase 1 and its comparable upregulation between sham operation and
injury. AMP hydrolysis changes were more brain-injury specific, with a
longer-lasting lymphocytic response induced by cortical stab injury (CSI). In
summary, CSI and sham operation induce the upregulation of the whole enzyme
chain for adenine nucleotide hydrolysis in lymphocytes, suggesting an
important roles of ectonucleotidases in the course of recovery after brain
injury.
Biological indication of heavy metal pollution in the areas of Donje Vlase and Cerje (southeastern Serbia) using epiphytic lichens
Authors: Stamenkovic S.S. , Mitrovic Tatjana , Cvetkovic V.J. , Krstic N.S. , Baosic Rada , Markovic Marija , Nikolic N.D. , Markovic V.Lj. , Cvijan M.V.
Published: February 2013

The performance of two epiphytic lichen species (Evernia prunastri (L.) Ach.
and Parmelia sulcata Taylor) as bioindicators of heavy metal pollution in
natural areas around the city of Nis (southeastern Serbia) were evaluated.
The concentration of 19 heavy metals in lichen samples was measured by
inductively coupled plasma-optical emission spectroscopy. For the majority of
the elements the concentrations found in Parmelia sulcata Taylor were higher
than in Evernia prunastri (L.) Ach. In addition, interspecific differences in
heavy metal accumulation between Evernia prunastri (L.) Ach. and Parmelia
sulcata Taylor are observed. Parmelia sulcata Taylor showed a tendency to
accumulate Fe, Mn, Ni and Ti while Evernia prunastri (L.) Ach. preferentially
concentrated Cu on both locations. A clear distinction between lithogenic
(Mn-Cu-Ti) and atmospheric elements (Ni-Co-Cr-Ag-Pb-Hg) was achieved by
cluster analysis.
The impact of climate elements on the diameter increment of Austrian pine (Pinus nigra Arn.) in Serbia
Authors: Cirkovic-Mitrovic Tatjana , Popovic V. , Brasanac-Bosanac Ljiljana , Rakonjac Lj. , Lucic A.
Published: February 2013

The aims of this paper were the analysis of climate elements and
Thornthwaite?s climate index, the study of the development of diameter and
current diameter increment of the Austrian pine trees from several artificial
stands in the Belgrade area, as well as an analysis of the influences of the
pluviometric regime and climate index on the current diameter increment of
the Austrian pine over the period 1985-2010. By comparative analysis and
statistical data procession, the correlation between the diameter increment
and climate characteristics was determined. In spite of the wide-held view
that the Austrian pine is a species that cannot make use of the capacity of
the best sites where it grows, is to a great extent able to react to
increased humidity, one of the most important site factors upon which the
growth of basic quantitative tree parameters directly depends.
Quercetin and lithium chloride modulate Wnt signaling in pluripotent embryonal carcinoma NT2/D1 cells
Authors: Mojsin Marija , Topalovic Vladanka , Marjanovic Jelena , Stevanovic Milena
Published: February 2013

Wnt signaling functions in numerous cellular activities such as cell fate
determination, patterning, and migration in embryogenesis, apoptosis, etc. In
this study, we used quercetin and lithium chloride to investigate modulations
of the Wnt signaling pathway in human pluripotent embryonal carcinoma NT2/D1
cell line. First, we optimized conditions for NT2/D1 cell treatments with
quercetin and lithium chloride and assessed their cytotoxic effects on the
cells, cell viability and proliferation rate. Our results showed that
induction of cell death by quercetin and LiCl is p53-dependent in NT2/D
cells. We also examined the degree of Wnt signaling modulations by analyzing
the expression of c-myc, a wellknown Wnt signaling target gene. Since the
retinoic acid induction of NT2/D1 cells is good in an in vitro model system
for human neural differentiation, studying Wnt signaling modulation in NT2/D1
would contribute to a better understanding of the mechanisms involved in
neural stem cell maintenance and human neural development.
Immunohistochemical evidence for the presence of a Vasoactive Intestinal Peptide, Neuropeptide Y, and Substance P, in rat adrenal cortex after acute heat stress
Authors: Petrovic-Kosanovic Dragana , Ukropina Mirela , Cakic-Milosevic Maja , Budec Mirela , Milosevic Verica , Koko Vesna
Published: February 2013

Immunohistochemistry revealed the presence of Vasoactive Intestinal Peptide
(VIP), Neuropeptide Y (NPY), and the absence of Substance P (SP)
immunoreactivity in the rat adrenal cortex. VIP- and NPY-immunoreactivity
were detected in nerve fibers around the small blood vessels projecting into
the capsule and cortical zones surrounding blood vessels and cortical cells.
After acute heat stress, VIP- and NPY-immunoreactivities in the nerve fibers
were reduced, probably as a result of the release of these peptides.
The chemical composition, antimicrobial and antioxidant activities of the essential oil of Salvia fruticosa growing wild in Libya
Authors: Giweli Abdulhamid , Dzamic Ana , Sokovic Marina , Ristic M.S. , Janackovic P. , Marin P.D.
Published: February 2013

The composition of essential oil isolated from Salvia fruticosa, wild growing
in Libya, was analyzed by GC and GC-MS. Forty-five compounds could be
identified. The essential oil contained 1,8-cineole (49.34%), camphor
(7.53%), ?-pinene (7.38%), myrcene (7.38%), ?-pinene (5.15%), ?-caryophyllene
(4.13%) and ?-terpineol (3.25). Antioxidant activity was analyzed using the
DPP H free radical scavenging method and low antioxidant activity was found
(IC50 = 15.53 mg/ml). The oil was also screened for its antimicrobial
activity against eight bacteria (four Gram-negative and four Gram-positive)
and eight fungi. The essential oil of S. fruticosa showed minimal inhibitory
activity (MIC) at 0.125-1.5 mg/ml and bactericidal (MBC) at 0.5-2.0 mg/ml. In
addition, it exhibited fungistatic (MIC) at 0.125-1.0 mg/ml and fungicidal
effect (MFC) at 0.125-1.5 mg/ml.