bluuebunny/crossref_metadata_2025 huggingface dataset:
A New Computational Model to Predict Ternary Phase Behaviour of Brine/Oil/Surfactant Mixtures for Chemical Enhanced Oil Recovery CEOR Methods
Authors: Adeeyo Yisa A. , Awang Mariyamni B. , El-Khatib Noaman
Published: July 2013

Surfactant flooding is an enhanced oil recovery process used to mobilize the residual oil by lowering the interfacial tension (IFT) between oil and water. When surfactants are mixed with brine and oil, oil in water, water in oil microemulsions could be formed with region of ultra low IFT. The ability to predict the number of phases formed, their relative amount, and compositions at a particular reservoir brine concentration is crucial for successful CEOR planning.

Equations of state (EOS) such as the Peng-Robinson (PR) and Soave-Redlich-Kwong (SRK) are usually used to predict the phase equilibrium. They require critical properties and accentric factors of the components. However, since oil and surfactants are not pure substances, they are treated as pseudo-components for which the pseudo critical properties must be estimated. Also, PR and SRK EOS are originally developed for non-ionic, non-polar and non-associating hydrocarbons. These pose some limitations in their application to surfactant/Brine/Oil mixture.

This study presents a new computational model to estimate surfactant/brine/oil ternary phase behaviour using PR EOS. In this study we have adopted group contribution model (GCM) using information from the molecular structure of the pseudo components for the estimation of their critical properties. A numerical solution is developed for solving the system of nonlinear equations governing the phase equilibrium by means of Newton-Raphson iterative procedure.

Phase behavior experiments were conducted at temperature of 50°C using Alfa Olefin Sulfonate (AOS) surfactant, decane and brine. Brine concentrations were varied at each temperature and phase relative amount and compositions were determined. The laboratory results were compared with the results predicted by the model. The study shows the level of reliability of our new predictive model. The model developed can be used in compositional simulation of surfactant flooding operations and should prove to be an invaluable tool in planning and evaluation of surfactant flooding processes.
Chemical EOR: Challenges for Full Field Simulation
Authors: Shaharudin M. Shahid , Jalan Shlok , Masoudi R.. , Othman M. B.
Published: July 2013

Chemical EOR projects were very active during 1980's, however, during 90's the interest in chemical EOR has fallen due to the low oil prices and also technical challenges that the methods poses. While surfactant flooding has difficult design considerations of chemicals, large capital requirements and is very sensitive to local reservoir heterogeneities, alkali can react strongly with minerals in the connate water and reservoir rocks may adversely impact the process. This complex process is yet to be understood. If the field is offshore, chemical EOR becomes even more challenging due to sophisticated logistics, incremental costs, highly deviated wells, larger well spacing and limited well slots on the platform. However, recently there has been a renewed interest in chemical flooding mainly due to valuable insights gained through chemical floods done in the past and better technical understanding of the processes and favorable economic conditions.

For robust production forecasts, various uncertainties due to complex chemical processes should be quantified thoroughly. Some of the important uncertainties for full field production forecasts are chemical adsorption on rock surface, interfacial tension (IFT) and residual oil saturation reduction by chemical. Proper coreflood experiments are critical to reduce these uncertainties. Careful matching of coreflood experiments in numerical simulations is also important which provides key inputs for full field forecast. Another important element in the successful commercial application for chemical EOR process is a well-designed pilot. After the completion of pilot, the results should be carefully matched in the simulation model. Once satisfactory match is obtained, the key step would be to upscale the results to the full field level.

Discussed in this paper are the impact of some of these uncertainties and the method used to reduce them. In this paper the workflow and key tasks in dealing with the simulation of chemical EOR process elements like residual oil saturation, IFT reduction and adsorption parameters are discussed. The results show that the incremental oil is very sensitive to the various simulation inputs.
Inline Viscosity Monitoring of Polymer Solutions Injected in Chemical Enhanced Oil Recovery Processes
Authors: Bonnier J.. , Rivas C.. , Gathier F.. , Quillien B.. , Thomas A..
Published: July 2013

The development of chemical enhanced oil recovery projects throughout the world is on a fast pace, led by a will to increase the final recovery of mature and newly developed hydrocarbon reservoirs The validation of the process is usually achieved by implementing an injection pilot; the goal is to understand, secure, and optimize the technology and to assess its efficiency on increasing final oil recovery for carefully determined capital and operational expenditures.

One of the key factors for a successful polymer flood is the polymer solution viscosity that must remain on target during the transport from its initial preparation, to the well head and down to the reservoir. Thus, a reliable method is required to measure and monitor the polymer solution viscosity on different points along the dissolution, dilution, mixing, and injection lines. This method must take into account the polymer solution characteristics among which the non-Newtonian behavior and sensitivity to mechanical and chemical degradations.

This paper presents recent developments of a specific in-line viscometer, which can measure the viscosity at low shear-rate, as per real reservoir conditions, with pressures ranging up to 250 barg. The equipment consists in a low flow, non-shearing pump, which circulates the solution through a given tube (length and diameter) where the pressure drop is measured and allows low-shear viscosity to be extrapolated. Calibration methods and first results are presented in this paper to illustrate the accuracy of the technology and potential installation benefits for chemical enhanced oil recovery operations. The viscometer is made of highly resistant material and can be implemented in all hazardous areas in remote mode without manual operations, no waste and very little maintenance.

This new device has been designed to solve the common issues encountered with the vast majority of commercial equipment that is not compatible with currently injected polyacrylamide solutions. It will also allow operators to gather reliable data compared to manual sampling methods that, in addition to requiring manpower, are not easy to conduct without degrading the polymer solutions.
Recovery of Oil from High Salinity Reservoir Using Chemical Flooding: From Laboratory to Field Tests
Authors: Shiau Ben , Hsu Tzu-Ping , Lohateeraparp Prapas , Rojas Mario , Budhathoki Mahesh , Raj Ajay , Wan Wei , Bang Sangho , Harwell Jeffrey H.
Published: July 2013

Reservoirs containing very high total dissolved solids and high hardness make the design of a surfactant polymer (SP) flood extremely difficult because surfactant tends to precipitate and separate under these conditions. Beside divalent ions, Ca2+, Mg2+, presence of iron in the brine can be a challenging issue. Different surfactant formulations are evaluated and incorporate cosurfactants and co-solvents which minimize viscous macroemulsions, promote rapid coalescence under Winsor Type III conditions, and stabilize the chemical solution by reducing precipitation and phase separation. The optimal surfactant formulations were further evaluated in one-dimensional sand packs and coreflood tests using Berea sandstone, reservoir oils, and brines at reservoir temperatures. Using similar injection protocols, 3 pore volumes of surfactant-only system, experimental results show the oil recovery ranging from 45 % to 70% of the residual oil (Sor) after water flooding. The level of surfactant loading is less than 0.5 wt%. A single-well test was conducted to confirm laboratory results in situ in the presence of high-salinity formation water containing 102,300 mg/L total dissolved solids (TDS). The aim of ongoing test is to confirm the effectiveness of the high-salinity surfactant-only formulation (0.46 wt% of surfactant). In this effort, we plan to conduct multiple single-well tests at different wells to minimize the design risks involved for the surfactant pilot test. A pilot test at a sandstone reservoir is scheduled to be performed in July of 2013 to further evaluate the effectiveness of surfactant formulation and address technical issues related to scale-up.
The Successful Implementation of a Novel Polymer EOR Pilot in the Low Permeability Windalia Field
Authors: Haynes Andrew K. , Clough Martyn D. , Fletcher Alistair J. , Weston Stuart
Published: July 2013

Barrow Island's Windalia reservoir is Australia's largest onshore waterflooding operation and has been under active waterflood since 1967. The highly heterogeneous reservoir consists of fine-grained, bioturbated argillaceous sandstone that is high in glauconite clay. The high clay content results in a low average permeability (5 md) despite high porosities (25-30%) and hence fracture stimulation is required to achieve economic production rates.

The Windalia reservoir and fluid properties preclude the use of traditional EOR technology, with thermal, miscible and mobility control processes all deemed unfeasible through screening studies. Consequently, the in-depth flow diversion mechanism was developed and applied, which utilizes a low molecular weight polymer to drive the growth of induced hydraulic fractures in the treated injection wells. A 3-injector pilot was executed involving polymer injection for two years, with no detrimental injectivity losses observed for polymer concentrations up to 750 ppm. Considerable fracture growth, oil production rate uplift and reduction in water cut were observed throughout the pilot pattern, in line with predictions: Fracture half-lengths increased from 6 ft to 400 ft in one injector and from 141 ft to 322 ft in anotherAn initial oil rate uplift of 38% relative to the production baseline was observed; a more conservative estimate suggested that at least half of this was attributable to the tertiary recovery processThe water-oil ratio was observed to fall from 15 to 11, similarly timed with the oil production increase.

These improvements were observed consistently throughout the pilot area and were distinct from the waterflood behavior elsewhere in the field. This paper briefly summarizes the technology screening and pilot execution stages, after which the results from the pilot are presented and discussed. This technology may be of use in other low-permeability waterfloods with induced injector fractures, for which traditional EOR practices are believed to be unfeasible.
Effects of Oil on Foam Generation and Propagation in Porous Media
Authors: Simjoo M.. , Zitha P. L.
Published: July 2013

Foaming of nitrogen stabilized by C14-16 alpha olefin sulfonate in natural sandstone porous media, previously subject to water flooding, was studied experimentally. Foam was generated in-situ by co-injecting gas and surfactant solution at fixed foam quality. Effect of surfactant concentration on the foam strength and foam propagation was examined. X-ray CT scans were obtained to visualize the foam displacement process and to determine fluid saturations at different times. The experiments revealed that stable foam could be obtained in the presence of water-flood residual oil. CT scan images, fluid saturation profiles and mobility reduction factors demonstrated that foam exhibited a good mobility control in the presence of water-flood residual oil. This was further confirmed by a delay in the gas breakthrough. The experiments also proved that immiscible foam displaced additional oil from water-flooded sandstone cores, supporting the idea that foam is potentially an effective EOR method. Foam flooding provided an incremental oil recovery ranging from 13±0.5% of the oil initially in place for 0.1 wt% foam to 29±2% for 1.0 wt% foam. Incremental oil due to foam flow was obtained first by a formation of an oil bank and then by a long tail production due to transport of dispersed oil within the flowing foam. The oil bank size increased with surfactant concentration, but the dispersed oil regime was less sensitive to the surfactant concentration.
Enhancing Oil Recovery of Low-Permeability Berea Sandstone through Optimized Nanofluids Concentration
Authors: Hendraningrat Luky , Li Shidong , Torsaeter Ole
Published: July 2013

Current global demand for fossil fuel such as oil is still high. This encourages oil and gas industries to improve their effort of finding new discoveries, developing technique and maximizing recovery of their current resources including in low-permeability reservoir. Enhanced oil recovery (EOR) is a technique to enhanced ultimate recovery. Since technology has been continuously developed such as nanotechnology/nano-size material, EOR methods have improved. One of them is Nano-EOR that triggered great attention in last decade. Nanoparticles may alter the reservoir fluid composition and rock-fluid properties to assist in mobilizing trapped oil. Most of observation from lab-scale reported that it seems potentially interesting for EOR.

Since reservoir management is very essential for the success of all improved/enhanced oil recovery (IOR/EOR) methods, optimizing nanofluids concentration is a proposed reservoir management to maximize oil recovery using Nano-EOR in this paper. Low-permeability water-wet Berea sandstones core-plugs with porosity ranged 13-15% and permeability ranged 5-20 mD were tested. A hydrophilic silica nanoparticles with primary particle size 7 nm was employed without surface treatment. Nanofluids with various concentration ranged 0.01 - 0.1 wt.% were synthesized with synthetic saline water for optimizing study. The wettability alteration due to nanofluids was observed; coreflood experiment was conducted and compared its displacement efficiency.

The results observed a range of nanofluids concentration that could maximize oil recovery in low-permeability water-wet Berea sandstone. Although contact angle of aqueous phase decreases as nanofluids concentration increase which means easier of oil to be released but we observed that higher concentration (e.g. 0.1 wt.%) has a tendency to block pore network and will decrease or even without additional oil recovery.

This study provides if concentration of nanofluids has an important parameter in Nano-EOR and could be optimized to maximize oil recovery of low-permeability water-wet Berea sandstone.
EOR: Challenges of Translating Fine Scale Displacement into Full Field Models-Part 2
Authors: Moreno J.. , Flew S.. , Gurpinar O..
Published: July 2013

Accurate realistic modeling of the physics governing the process occurring during an EOR displacement is an important challenge the industry is facing when trying to understand and evaluate the potential enhanced-oil-recovery may bring to a given reservoir. Numerical models have been widely used for this task, displacing the traditional analytical techniques under the premise of more reliable results as a function of a detailed representation of the reservoir recovery mechanisms within the models, and often time models which, typically were designed for primary and/or secondary depletion processes are used directly for the tertiary evaluation. This paper is a continuation of an early investigation aimed to address the main challenges of modeling the fine scale displacements with a full field numerical model.

The effects of model resolution, relative permeability up-scaling and force balance for immiscible displacements were investigated in our first paper. Here we concentrate on the effects of reservoir heterogeneity together with model resolution for both miscible and immiscible displacements. Up-scaling challenges are presented as a function of the displacement type and force balance, as well as the effect of fine level heterogeneity and viscous and capillary forces balance during EOR injection processes.
IL-1β Inhibits Human Osteoblast Migration
Authors: Hengartner Nina-Emily , Fiedler Jörg , Ignatius Anita , Brenner Rolf E.
Published: July 2013

Bone has a high capacity for self-renewal and repair. Prolonged local secretion of interleukin 1β (IL-1β), however, is known to be associated with severe bone loss and delayed fracture healing. Since induction of bone resorption by IL-1β may not sufficiently explain these pathologic processes, we investigated,in vitro, if and how IL-1β affects migration of multipotent mesenchymal stromal cells (MSC) or osteoblasts. We found that homogenous exposure to IL-1 β significantly diminished both nondirectional migration and site-directed migration toward the chemotactic factors platelet-derived growth factor (PDGF)-BB and insulinlike growth factor 1 (IGF-1) in osteoblasts. Exposure to a concentration gradient of IL-1β induced an even stronger inhibition of migration and completely abolished the migratory response of osteoblasts toward PDGF-BB, IGF-1, vascular endothelial growth factor A (VEGF-A) and the complement factor C5a. IL-1β induced extracellular signal-regulated kinases 1 and 2 (ERK1/2) and c-Jun N-terminal kinases (JNK) activation and inhibition of these signaling pathways suggested an involvement in the IL-1β effects on osteoblast migration. In contrast, basal migration of MSC and their migratory activity toward PDGF-BB was found to be unaffected by IL-1β. These results indicate that the presence of IL-1β leads to impaired recruitment of osteoblasts which might influence early stages of fracture healing and could have pathological relevance for bone remodeling in inflammatory bone disease.
TRPV1 Gates Tissue Access and Sustains Pathogenicity in Autoimmune Encephalitis
Authors: Paltser Geoffrey , Liu Xue Jun , Yantha Jason , Winer Shawn , Tsui Hubert , Wu Ping , Maezawa Yuko , Cahill Lindsay S. , Laliberté Christine L. , Ramagopalan Sreeram V. , DeLuca Gabriele C. , Sadovnick A. Dessa , Astsaturov Igor , Ebers George C. , Henkelman R. Mark , Salter Michael W. , Dosch H.-Michael
Published: July 2013

Multiple sclerosis (MS) is a chronic progressive, demyelinating condition whose therapeutic needs are unmet, and whose pathoetiology is elusive. We report that transient receptor potential vanilloid-1 (TRPV1) expressed in a major sensory neuron subset, controls severity and progression of experimental autoimmune encephalomyelitis (EAE) in mice and likely in primary progressive MS. TRPV1−/−B6 congenics are protected from EAE. Increased survival reflects reduced central nervous systems (CNS) infiltration, despite indistinguishable T cell autoreactivity and pathogenicity in the periphery of TRPV1-sufficient and -deficient mice. The TRPV1+neurovascular complex defining the blood-CNS barriers promoted invasion of pathogenic lymphocytes without the contribution of TRPV1-dependent neuropeptides such as substance P In MS patients, we found a selective risk-association of the missense rs877610 TRPV1 single nucleotide polymorphism (SNP) in primary progressive disease. Our findings indicate that TRPV1 is a critical disease modifier in EAE, and we identify a predictor of severe disease course and a novel target for MS therapy.
Molecular Expression and Characterization of Erythroid-Specific 5-Aminolevulinate Synthase Gain-of-Function Mutations Causing X-Linked Protoporphyria
Authors: Bishop David F. , Tchaikovskii Vassili , Nazarenko Irina , Desnick Robert J.
Published: July 2013

X-linked protoporphyria (XLP) (MIM 300752) is a recently recognized erythropoietic porphyria due to gain-of-function mutations in the erythroid-specific aminolevulinate synthase gene (ALAS2). Previously, two exon 11 small deletions, c.1699_1670ΔAT (ΔAT) and c.1706_1709ΔAGTG (ΔAGTG), that prematurely truncated or elongated the ALAS2 polypeptide, were reported to increase enzymatic activity 20- to 40-fold, causing the erythroid accumulation of protoporphyrins, cutaneous photosensitivity and liver disease. The mutant ΔAT and ΔAGTG ALAS2 enzymes, two novel mutations, c.1734ΔG (ΔG) and c.1642C>T (p.Q548X), and an engineered deletion c.1670–1671TC>GA p.F557X were expressed, and their purified enzymes were characterized. Wild-type and ΔAGTG enzymes exhibited similar amounts of 54- and 52-kDa polypeptides on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), whereas the ΔAT and p.F557X had only 52-kDa polypeptides. Compared to the purified wild-type enzyme, ΔAT, ΔAGTG and Q548X enzymes had increased specific activities that were only 1.8-, 3.1- and 1.6-fold, respectively. Interestingly, binding studies demonstrated that the increased activity Q548X enzyme did not bind to succinyl-CoA synthetase. The elongated ΔG enzyme had wild-type specific activity, kinetics and thermostability; twice the wild-type purification yield (56 versus 25%); and was primarily a 54-kDa form, suggesting greater stability in vivo. On the basis of studies of mutant enzymes, the maximal gain-of function region spanned 57 amino acids between 533 and 580. Thus, these ALAS2 gain-of-function mutations increased the specific activity (ΔAT, ΔAGTG and p.Q548X) or stability (ΔG) of the enzyme, thereby leading to the increased erythroid protoporphyrin accumulation causing XLP.
Differential microRNA Profiles and Their Functional Implications in Different Immunogenetic Subsets of Chronic Lymphocytic Leukemia
Authors: Papakonstantinou Nikos , Ntoufa Stavroula , Chartomatsidou Elisavet , Papadopoulos Giorgio , Hatzigeorgiou Artemis , Anagnostopoulos Achiles , Chlichlia Katerina , Ghia Paolo , Muzio Marta , Belessi Chrysoula , Stamatopoulos Kostas
Published: July 2013

Critical processes of B-cell physiology, including immune signaling through the B-cell receptor (BcR) and/or Toll-like receptors (TLRs), are targeted by microRNAs. With this in mind and also given the important role of BcR and TLR signaling and microRNAs in chronic lymphocytic leukemia (CLL), we investigated whether microRNAs could be implicated in shaping the behavior of CLL clones with distinct BcR and TLR molecular and functional profiles. To this end, we examined 79 CLL cases for the expression of 33 microRNAs, selected on the following criteria: (a) deregulated in CLL versus normal B-cells; (b) differentially expressed in CLL subgroups with distinct clinicobiological features; and, (c) if meeting (a) + (b), having predicted targets in the immune signaling pathways. Significant upregulation of miR-150, miR-29c, miR-143 and miR-223 and downregulation of miR-15a was found in mutated versus unmutated CLL, with miR-15a showing the highest fold difference. Comparison of two major subsets with distinct stereotyped BcRs and signaling signatures, namely subset 1 [IGHV1/5/7-IGKV1(D)-39, unmutated, bad prognosis] versus subset 4 [IGHV4-34/IGKV2-30, mutated, good prognosis] revealed differences in the expression of miR-150, miR-29b, miR-29c and miR-101, all down-regulated in subset 1. We were also able to link these distinct microRNA profiles with cellular phenotypes, importantly showing that, in subset 1, miR-101 downregulation is associated with overexpression of the enhancer of zeste homolog 2 (EZH2) protein, which has been associated with clinical aggressiveness in other B-cell lymphomas. In conclusion, specific miRNAs differentially expressed among CLL subgroups with distinct BcR and/or TLR signaling may modulate the biological and clinical behavior of the CLL clones.
Impact of Seawater on Distribution of Fluoride and Other Ions in Groundwater of Diplo Area, Thar Desert Pakistan
Authors: Rafique Tahir , Naseem Shahid , Usmani Tanzil Haider , Bhanger Muhammad Iqbal , Shirin Khaula
Published: July 2013

The role of seawater dilution, along with other water‐quality components, has been studied to determine the causes of spatial distribution of high fluoride concentrations in the groundwater of the Diplo sub‐district, Thar Desert, Pakistan. Fluoride ion concentration ranges of up to 7.60 mg/L were discovered, with mean and median values of 1.66 and 1.34 mg/L, respectively. Estimates based on the total dissolved solid (TDS) ratio show the impact of seawater intrusion at a percentage of around 8.05% in the groundwater. The major ion chemistry of water in the central diamond shape of the Piper diagram precisely demarcates the phenomenon of the intrusion of seawater into the study area. The plots of Na+K vs. Ca+Mg (meq/L) and log Cl (mg/L) vs. log Ca+Mg/Na+K (meq/L) indicate a mixing of freshwater with seawater. The molar Na/Na+Cl and Ca/Ca+SO4 ratios of the groundwater, and correlation matrices of major ion chemistry, also show a blending of groundwater with seawater. Mutual relationships among Li+, Sr2+, and Cl− ions further substantiate the marked influence of the marine environment on the groundwater in the study area.
Performance Evaluation and Modeling of Synthetic‐Fiber Barrier in the Treatment of Turbid Water
Authors: Yu Jianghua , Kim Youngchul
Published: July 2013

A synthetic‐fiber barrier for the removal of turbidity in water was developed and tested using a laboratory scale channel. The effects of hydraulics (flow rate and exchange rate); density current caused by temperature and turbidity difference; barrier conditions (thickness, number and shape); and particle size were analyzed. The experimental results indicated that removal efficiency was positively related to barrier thickness and number, was inversely related to the strength of the density current, and was also negatively affected by the flow rate and exchange rate. A wedged barrier was found to work better than a rectangular one when the same amount of fiber was used. Based on the experimental work, empirical models for the removal efficiency and barrier design were established using dimensionless groups. The modeling results indicated that the predicted values were consistent with the experimental work and the increases and decreases in the performance were suitably simulated.
Hydrochemical Status of an Acidic Mining Lakein Çan‐Çanakkale, Turkey
Authors: Okumusoglu Deniz , Gündüz Orhan
Published: July 2013

An acidic mining lake located in Çan, Turkey was investigated to assess its water quality status and potential risk for environment. Morphological studies and water quality sampling were conducted to determine vertical and areal distributions of numerous water quality criteria and to assess the general status of the lake. The results revealed that the lake had an average pH of 2.28 and an average electrical conductivity value of 5925 μS/cm. The dissolved oxygen ranged between 0.83 and 6.45 mg/L and demonstrated a significant vertical profile. Sulfate was found to be the dominant anion with an average level of 5912.5 mg/L depicting the extent of pyrite oxidation. Similarly, aluminum, iron and manganese levels were extremely high with averages of 290155, 172344 and 91342 μg/L, respectively. With these levels, the lake is classified to be a Class 4 water resource according to pertinent regulations and is in need of immediate action for rehabilitation.
Critical Review: Regulatory Incentives and Impediments for Onsite Graywater Reuse in the United States
Authors: Yu Zita L.T. , Rahardianto Anditya , DeShazo J.R. , Stenstrom Michael K. , Cohen Yoram
Published: July 2013

Graywater is a potential water source for reducing water demand. Accordingly, a review was undertaken of graywater reuse regulations and guidelines within the 50 United States. Major issues considered included acceptability for graywater segregation as a separate wastewater stream, allowable graywater storage, onsite treatment requirements, and permitted graywater use applications. Existing regulations and plumbing codes in the different states suggest that there are impediments to overcome but also potential incentives for graywater reuse. It is encouraging that regulations in 29 states promote safe graywater reuse, but there are also inconsistencies between plumbing codes and other regulations within and among the 50 states. Impediments to graywater reuse include disallowances of graywater segregation or collection, and restriction of graywater reuse to mostly subsurface irrigation with limited indoor use permission. Ease on restrictions and guidelines to promote development of low‐cost and proven treatment technologies are needed to promote graywater reuse.
Multielement determination using inductively coupled plasma optical emission spectrometry for metal characterization of water from artesian wells in Semberija region: Multivariate analysis of data
Authors: Pavlovic Aleksandra , Laketic Tamara , Mitic Snezana , Savic Milenko , Tosic Snezana , Djordjevic Miodrag
Published: July 2013

The concentrations of fifteen metals (Mg, Na, Ca, K, Se, Zn, Mn, Fe, Pb, Cr,
Cu, Cd, Sb, Ni, Co) were determined in water from ten artesian wells (AW) in
Semberija to obtain a general metal profile of water in this region.
Principal components analysis (PCA) was used in this classification. Using
principal component analysis two factors controlling the metal variability
were obtained, which accounted for nearly 71.5% of the total variance.
Natural (lithogenic) factor is represented by PC1, while anthropogenic factor
is represented by PC2. PC1 with high contribution of Mn, Mg, Na, K, Ca, Zn
and Se accounting for 41.84% of the total variance, while PC2 exhibits high
loading for Cd, Ni, Sb, Cr and Pb (29.66%). Three general areas (clusters)
with different metal characteristics were detected. Water from artesian wells
in first cluster (AW1, AW2, AW3, AW4, AW5 and AW6) had much higher metal
concentration compared with those in the second (AW7, AW8 and AW9) and third
cluster (AW10). That is as a result of anthropogenic inputs. Also, the
analysis of water demonstrated slightly elevated values for Mn
(concentrations up to 0.176 mg/L), while concentrations of the other
investigated elements are below the values recommended by the World Health
Organization (WHO) and the United States Environmental Protection Agency (US
EPA).
Parenteralna Uporaba Protibolečinskih Zdravil Pri Bolečini V Križu V Družinski Medicini / Parenteral Use of Analgesics in Low Back Pain in Family Medicine
Authors: Petek Šter Marija , Švab Igor , Kalan Živčec Gordana
Published: July 2013

Izvleček

Izhodišča: Parenteralna uporaba zdravil za lajšanje bolečine v križu se zaradi odsotnosti dokazov o njihovi večji učinkovitosti in dodatnem tveganju za zaplete odsvetuje. Namen raziskave je bil ugotoviti, kolikšen delež in kateri bolniki z bolečino v križu so dobili zdravilo v injekciji.

Metode: V presečni študiji smo med 12.596 zaporednimi obiski pri 42 naključno izbranih zdravnikih družinske medicine analizirali vse obiske zaradi bolečine v križu. Na vzorcu bolnikov v starosti med 18 in 65 let smo analizirali pogostnost in dejavnike, ki vplivajo na odločitev za uporabo protibolečinskih zdravil v injekciji.

Rezultati: Zaradi bolečine v križu je zdravnika obiskalo 819 (6,5 %) vseh obiskovalcev ambulante, 300 (2,4 %) bolnikov z akutno in 519 (4,1 %) s kronično bolečino v križu. Injekcijo je prejelo 132 (20,7 %) obiskovalcev z bolečino v križu, starih med 18 in 65 let. Med dejavniki, ki so se v multivariatnem modelu izkazali kot pomembni pri odločitvi za injekcijo, so bili dejavniki bolnika (višja starost, nižja stopnja izobrazbe), vrsta bolečine v križu (akutna radikularna bolečina) in dejavniki zdravnika (zdravnik specialist, nižja starost). Razlike v odločitvi za injekcijo so bile med zdravniki zelo velike: 8 od 42 zdravnikov injekcije ni dalo niti enemu bolniku, medtem ko se je en zdravnik za injekcijo odločil pri 19 od 32 (59,4 %) bolnikih.

Zaključki: Velike razlike med zdravniki v pogostnosti odločitve za uporabo protibolečinskih zdravil v injekciji pri bolečini v križu kažejo na potrebo po usmerjeni intervenciji, katere cilj bi bil poenotiti delo zdravnikov ter povečati kakovost in varnost obravnave bolnikov.
Latin America from crisis to sustainable growth: image change and new development paradigms
Authors: Kholina Veronika N. , Massarova Alyona R.
Published: July 2013

The aim of the article is to identify the role of Latin America in the global economy between 1990 and 2010. The analysis is based on the indicators that define social and economic potential (regional GNI, GNI per capita, growth rates, share in global production output, etc.). The article examines in detail the structural and regional shifts in Latin America’s foreign trading: the share of manufactures in Latin American exports has shrunk sharply since 2000; primary commodities have become more important for the region’s trade; China has become a privileged trading partner for Latin America; the region’s resilience to the crisis has renewed trade interest from the EU ; the USA’s share in the region’s trade has reduced. The analysis allowed a proposal for decision methods addressing major issues in the region’s trade through the diversification of Latin American export and the intensification of intra-regional trade.
Evaluating the Effectiveness of the Family Employment Awareness Training in Kansas: A Pilot Study
Authors: Francis Grace , Gross Judith M.S. , Turnbull Rud , Parent-Johnson Wendy
Published: July 2013

Working in competitive employment (employment in community settings with nondisabled peers for minimum wage or higher) has many positive benefits for people with disabilities who have individualized support needs (Johannesen, McGrew, Griss, & Born, 2007). Nonetheless, many of these individuals work in segregated settings or are unemployed entirely (National Disability Rights Network, 2011). The Family Employment Awareness Training (FEAT) in Kansas sought to increase expectations for competitive employment and knowledge about employment services, supports, and resources among people with disabilities who have individualized support needs, their families, and the professionals that support them to increase competitive employment outcomes. Our findings from this pilot study indicate that FEAT succeeded in raising expectations and knowledge among these individuals.
Lentiviral Vectors for Cancer Immunotherapy and Clinical Applications
Authors: Liechtenstein Therese , Perez-Janices Noemi , Escors David
Published: July 2013

The success of immunotherapy against infectious diseases has shown us the powerful potential that such a treatment offers, and substantial work has been done to apply this strategy in the fight against cancer. Cancer is however a fiercer opponent than pathogen-caused diseases due to natural tolerance towards tumour associated antigens and tumour-induced immunosuppression. Recent gene therapy clinical trials with viral vectors have shown clinical efficacy in the correction of genetic diseases, HIV and cancer. The first successful gene therapy clinical trials were carried out with onco(g-)retroviral vectors but oncogenesis by insertional mutagenesis appeared as a serious complication. Lentiviral vectors have emerged as a potentially safer strategy, and recently the first clinical trial of patients with advanced leukemia using lentiviral vectors has proven successful. Additionally, therapeutic lentivectors have shown clinical efficacy for the treatment of HIV, X-linked adrenoleukodystrophy, and b-thalassaemia. This review aims at describing lentivectors and how they can be utilized to boost anti-tumour immune responses by manipulating the effector immune cells.
Simple Urban Simulation Atop Complicated Models: Multi-Scale Equation-Free Computing of Sprawl Using Geographic Automata
Authors: Torrens Paul , Kevrekidis Yannis , Ghanem Roger , Zou Yu
Published: July 2013

Reconciling competing desires to build urban models that can be simple and complicated is something of a grand challenge for urban simulation. It also prompts difficulties in many urban policy situations, such as urban sprawl, where simple, actionable ideas may need to be considered in the context of the messily complex and complicated urban processes and phenomena that work within cities. In this paper, we present a novel architecture for achieving both simple and complicated realizations of urban sprawl in simulation. Fine-scale simulations of sprawl geography are run using geographic automata to represent the geographical drivers of sprawl in intricate detail and over fine resolutions of space and time. We use Equation-Free computing to deploy population as a coarse observable of sprawl, which can be leveraged to run automata-based models as short-burst experiments within a meta-simulation framework.
The Organization of the Quorum Sensing luxI/R Family Genes in Burkholderia
Authors: Choudhary Kumari , Hudaiberdiev Sanjarbek , Gelencsér Zsolt , Gonçalves Coutinho Bruna , Venturi Vittorio , Pongor Sándor
Published: July 2013

Members of the Burkholderia genus of Proteobacteria are capable of living freely in the environment and can also colonize human, animal and plant hosts. Certain members are considered to be clinically important from both medical and veterinary perspectives and furthermore may be important modulators of the rhizosphere. Quorum sensing via N-acyl homoserine lactone signals (AHL QS) is present in almost all Burkholderia species and is thought to play important roles in lifestyle changes such as colonization and niche invasion. Here we present a census of AHL QS genes retrieved from public databases and indicate that the local arrangement (topology) of QS genes, their location within chromosomes and their gene neighborhoods show characteristic patterns that differ between the known Burkholderia clades. In sequence phylogenies, AHL QS genes seem to cluster according to the local gene topology rather than according to the species, which suggests that the basic topology types were present prior to the appearance of current Burkholderia species. The data are available at http://net.icgeb.org/burkholderia/.
Immune Signaling and Antimicrobial Peptide Expression in Lepidoptera
Authors: Casanova-Torres Ángel , Goodrich-Blair Heidi
Published: July 2013

Many lepidopteran insects are agricultural pests that affect stored grains, food and fiber crops. These insects have negative ecological and economic impacts since they lower crop yield, and pesticides are expensive and can have off-target effects on beneficial arthropods. A better understanding of lepidopteran immunity will aid in identifying new targets for the development of specific insect pest management compounds. A fundamental aspect of immunity, and therefore a logical target for control, is the induction of antimicrobial peptide (AMP) expression. These peptides insert into and disrupt microbial membranes, thereby promoting pathogen clearance and insect survival. Pathways leading to AMP expression have been extensively studied in the dipteran Drosophila melanogaster. However, Diptera are an important group of pollinators and pest management strategies that target their immune systems is not recommended. Recent advances have facilitated investigation of lepidopteran immunity, revealing both conserved and derived characteristics. Although the general pathways leading to AMP expression are conserved, specific components of these pathways, such as recognition proteins have diverged. In this review we highlight how such comparative immunology could aid in developing pest management strategies that are specific to agricultural insect pests.
A Fundamental Limitation of Small Diameter Single-Walled Carbon Nanotube Synthesis—A Scaling Rule of the Carbon Nanotube Yield with Catalyst Volume
Authors: Sakurai Shunsuke , Inaguma Masayasu , Futaba Don , Yumura Motoo , Hata Kenji
Published: July 2013

Understanding the fundamental mechanisms and limiting processes of the growth of single-walled carbon nanotube (SWCNT) would serve as a guide to achieve further control on structural parameters of SWCNT. In this paper, we have studied the growth kinetics of a series of SWCNT forests continuously spanning a wide range of diameters (1.9–3.2 nm), and have revealed an additional fundamental growth limiting process where the mass of the individual SWCNT is determined by the individual catalyst volume. Calculation of the conversion rate of carbon atoms into CNTs per Fe atom is 2 × 102 atoms per second. This rate limiting process provides an important understanding where the larger diameter SWCNT would grow faster, and thus be more suited for mass production.
Efficient One-Pot Synthesis of 5-Chloromethylfurfural (CMF) from Carbohydrates in Mild Biphasic Systems
Authors: Gao Wenhua , Li Yiqun , Xiang Zhouyang , Chen Kefu , Yang Rendang , Argyropoulos Dimitris
Published: July 2013

5-Halomethylfurfurals can be considered as platform chemicals of high reactivity making them useful for the preparation of a variety of important compounds. In this study, a one-pot route for the conversion of carbohydrates into 5-chloromethylfurfural (CMF) in a simple and efficient (HCl-H3PO4/CHCl3) biphasic system has been investigated. Monosaccharides such as D-fructose, D-glucose and sorbose, disaccharides such as sucrose and cellobiose and polysaccharides such as cellulose were successfully converted into CMF in satisfactory yields under mild conditions. Our data shows that when using D-fructose the optimum yield of CMF was about 47%. This understanding allowed us to extent our work to biomaterials, such as wood powder and wood pulps with yields of CMF obtained being comparable to those seen with some of the enumerated mono and disaccharides. Overall, the proposed (HCl-H3PO4/CHCl3) optimized biphasic system provides a simple, mild, and cost-effective means to prepare CMF from renewable resources.
Le nom de mesure λíτρα : essai lexical
Authors: Lejeune Michel
Published: July 2013

Emprunté au sicule lors de la colonisation, le nom de mesure λίτρα n'a jamais été un terme grec de plein exercice. D'abord (jusqu'au — IIIe s.) c'est une γλῶττα du grec de Sicile. Ensuite, le mot a été senti et employé comme calque de lat. lîtra. Nos dictionnaires manquent à distinguer ces deux phases, et à souligner, dans l'une comme dans l'autre, la marginalité du mot.
Le statut des agriculteurs dans la cité grecque idéale au IVe siècle avant J.-C
Authors: Fouchard Alain
Published: July 2013

Les statuts des agriculteurs dans les cités idéales des Ve et IVe siècles reflètent la diversité de signification du terme γεωργός et la variété des statuts réels de ceux qu'il nous est commode d'appeler «les petits paysans». Les théoriciens acceptent mal que des travailleurs de la terre aient accès à l'armement hoplitique et à la souveraineté, voire à la citoyenneté. Étude d'Hippodamos, Platon (République, Lois, question de l'Atlantide), Aristote (Politique, VII), Phaléas.
Le Γυμναστικός de Philostrate a-t-il une signification littéraire ?
Authors: Billault Alain
Published: July 2013

Le Γυμναστιχός aborde des thèmes divers dans des perspectives multiples. L'on peut l'interpréter en le rapprochant des autres textes du Corpus Philostrateum. L'on y retrouve alors les principaux traits de l'esthétique littéraire de Philostrate qui veut traiter son sujet de manière exhaustive et fait de la tradition qui le concerne un exposé à la fois encyclopédique, original et riche en interprétations personnelles.
Médecine et botanique : le silphion dans l'œuvre d'Oribase
Authors: Roques Denis
Published: July 2013

Un relevé exhaustif des mentions du silphion dans l'œuvre d'Oribase prouve à l'envi que cette plante, notamment sa variété cyrénéenne, était non seulement connue des manuels de pharmacopée du IVe s. ap. J.-C, mais encore couramment utilisée à cette époque. Contredisant les assertions de Strabon et de Pline sur la disparition du silphion de Cyrénaïque au début du Haut-Empire, le témoignage d'Oribase rejoint celui d'autres auteurs, notamment Synésios de Cyrène, sur la permanence du commerce de cette plante au cours du Bas-Empire.
À propos de la place ontologique du démiurge dans le système philosophique d'Hiéroclès le néoplatonicien. Dernière réponse à M. Aujoulat
Authors: Hadot Ilsetraut
Published: July 2013

Dans cet article, qui complète celui qui était paru dans Rev. Et. Gr., CIII (1990), p. 241-262, l'auteur produit une deuxième série d'arguments qui a pour but de réfuter la thèse principale du livre de N. Aujoulat, Le néoplatonisme alexandrin : Hiéroclès d'Alexandrie, Leiden 1986, selon laquelle la philosophie d'Hiéroclès, influencé par le christianisme, ne connaîtrait pas d'entité ontologique supérieure à celle du démiurge.
Socrate et son double
Authors: Inglessis-Margellos Cécile
Published: July 2013

Pour préserver la cohérence de la personnalité et du message de Socrate, les critiques s'évertuent à rendre aux dialogues dits «socratiques» de Platon une univocité limpide, en gommant les contradictions gênantes, comme celle qui surgit entre Γ Apologie de Socrate et le Criton, à propos de la notion épineuse de Y obéissance civile. L'insuccès des entreprises «conciliatrices» est dû à l'irréductibilité de la contradiction, qui découle de la dualité du statut de Socrate dans ces deux œuvres : statut de philosophe et simultanément statut d'être humain et de citoyen intégré dans sa «polis». Raconter et réhabiliter son Maître sur ce double plan est la tâche impossible à laquelle s'attelle l'«hagiographe» Platon.
Structured Outpatient Peritoneal Dialysis Catheter Insertion is Safe and Cost-Saving
Authors: Salonen Tapani E. , Saha Heikki
Published: July 2013

Background

Data about outcomes and costs for peritoneal catheter insertion on an outpatient basis are scarce.

Methods

Using patient files, all peritoneal dialysis (PD) catheter insertions performed between 2004 and 2009 in a single-center tertiary care institution for adult patients were located. Patient demographics, complications, hospitalizations, survival, and treatment modality changes were recorded. Procedure-related expenses were valued as actual production costs.

Results

During the study period, 106 PD catheters were inserted. In 46 cases, the patients were admitted electively for catheter insertion; 19 catheters were placed during admission for other medical reasons; and 41 catheters were placed on an outpatient basis. Among the study patients (54.7 ± 16.0 years of age), 45% were diabetic. Early (<30 days) catheter-related complications occurred in 22% of patients. The incidences of technique failure and any complication within 90 days were 10% and 38% respectively. The occurrence of complications was not statistically significantly different for outpatients and electively admitted patients. Average costs for catheter insertion were higher in electively hospitalized patients than in outpatients (€2320 ± €960 vs €1346 ± €208, p < 0.000).

Conclusions

Compared with an inpatient procedure, outpatient insertion of a PD catheter results in similar outcomes at a lower cost.