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Conformance improvement is commonly referred to as the action of improving the drive-fluid sweep efficiency during an oil- recovery flooding operation. This technical note highlights the authors lessons learned during the field application of one of the most widely used and quite successful conformance technologies, which is Cr(III)-carboxylate/acrylamide-polymer (CC/AP). To date, the authors have been involved in the analysis, candidate selection, design, field application and post-treatment evaluation of ±700 injection well treatments over the last 25 years. A look back to the earliest treatment designs and field applications as compared to the more recent applications, clearly shows that we have made advancements to achieve better and more consistent results. These changes have occurred gradually over time as new lessons learned are continuously applied to improve treatment strategies and results.

The aim of this article is to determine the relationship between architecture and teaching, providing functional architecture models that are capable of absorbing the teaching load for movement and, fundamentally, for the development of kinesthetic intelligence (Howard Gardner). For this, we will establish a metric range of spatial proportions, m2/student ratio, in accordance with the activities performed on the BAPNE method. This study will focus on students of Pre-school and Primary Education, providing specific standing architectural models and the minimum requirements for a classroom, as well as determining whether a space is suitable or not for the proposed activities. The method includes analyzing architecture of the basic teaching room, approaching other education systems (Dalcroze, Montessori) and determining the differences between those systems and BAPNE. This study is carried out by architects and engineers, directly noting the architectural needs that current teaching requires for user stimulation.

El sobrehumedecimiento del suelo agravado por los efectos de cambio climático global es un fenómeno que afecta a plantas y microorganismos en varias regiones del mundo. La presencia de actividad endófita en la caña de azúcar de cepas de Azospirillum brasilense puede constituir una alternativa sustentable debido a la distribución universal de esta bacteria y a sus variados efectos benéficos en el crecimiento y desarrollo de las plantas. En un suelo Typic Haplustert del Valle del Río Cauto, en la región oriental de Cuba se plantó un experimento en bloques al azar, con la variedad de caña de azúcar C120-78, obtenidas por cultivo “in vitro”, inoculadas y sin inocular con la bacteria Azospirillum brasilense, cepa 8 del INICA, en condiciones normales y con el suelo sobresaturado de agua, con el objetivo de determinar la influencia que ejerce esta cepa bacteriana en indicadores del crecimiento y desarrollo de esta variedad, en ciclo de caña planta. Se demostró que para el pol en caña, t caña ha-1, t pol ha-1 y desarrollo del sistema radical, a los doce meses de edad, la presencia de la bacteria en el suelo no sobresaturado de agua mostró los mejores resultados, lo que demuestra que la carencia de oxígeno en el suelo es un elemento limitante para la actividad de esta cepa bacteriana y el normal crecimiento y desarrollo de la caña de azúcar.

The anti-phlogistic effect of dietary vitamin E supplementation on the acute inflammation observed in experimental lens-induced uveitis in Brown Norway rats was studied. The effects of vitamin E were examined using histopathologic parameters as well as by measuring the levels of arachidonic acid metabolites. Histologic examination of the eyes revealed that the vitamin E-deficient animals had the most severe destruction of the retina, while those animals receiving the vitamin E-supplemented diet exhibited the best preservation of the retinal architecture. Levels of arachidonic acid metabolites, as determined by radioimmunoassay, were significantly higher in vitamin E deficient rats as compared with rats on a normal diet.

En un experimento llevado a cabo en un suelo Vertisol del Valle del Río Cauto en Cuba se evaluó el efecto del exceso de agua sobre el desarrollo del sistema radical de seis genotipos de caña de azúcar. Se uso un diseño de parcelas divididas, donde la presencia o no de exceso de agua en el suelo era la parcela y los genotipos eran las subparcelas. Los tratamientos fueron 12 y consistieron en los genotipos C86-12, C86-456, C90-317, C87-51, C1051-73 y C12078, sometidos o no al exceso de agua en el suelo. Se encontró que la Intensidad del Estrés (IE), redujo en un 17% la profundidad radical en el primer ciclo, mientras que para la primera soca se redujo en un 11%, con marcada diferencia entre genotipos. Los genotipos menos afectados fueron C86-12, C86-456 y C90-317, lo

This study is intended to show that it is possible to reduce risks, time and costs in well drilling through application of Geomechanics in marginal fields. It refers to the Oritupano-Leona field, East Venezuela, which has more than 700 wells drilled from 1938, 29 of which are horizontal wells. In spite of the production success, 6 over 29 wells, 25%, presented problems due to hole instability that lead to several stuck pipes, sidetracks and down time. Drilling parameters of 23 horizontal wells, operational problems, geomechanical information and regional geology were considered for this analysis. Problems associated to mechanical/chemical instability and operational problems were identified. Geomechanical parameters were calculated and analyzed with the specialized software considering pore pressures, mud density, minifrac and electrical logs, where the stress direction was studied with the interpretation of imaging logs and review of the regional stresses. A friction diagram adjusted to the wide of the breakout was applied, whereas vertical stresses were calculated through density log integration. Rock mechanical parameters were product of RSD tests that included rock mechanical resistance analysis (UCS), determination of the internal friction angle and the Poisson's ratio and Young modulus, calculated with the use of neural networks. Drilling events were visualized in order to define the stability frame of the area for the different operational parameters based in geomechanical parameters previously calculated. With this data a new well design was elaborated integrating trajectory optimization and operational parameters in order to diminish the stability problems. Different mechanical instability values were identified in the study in three zones of the field, and the safe operating window for drilling and operational parameters was identified for each one, guarantying hole cleaning. The application of the criteria and recommendations of the results of this study had an outstanding impact on the horizontal well drilling in the Oritupano-Leona field. In 2005, a new record was established with the drilling of the ORM-174, which is the fastest horizontal well drilled in the field history. Two other wells were drilled in 2006 with excellent results.

This paper describes 12 history cases of the successful applications of Alternate Path (shunt tube) Technology in wells in Bachaquero Lago, Tía Juana Lago and Lagomedio fields, in Lake Maracaibo.The use of divergent tubes combined with packoff in these wells, allowed to complete two zones in a single trip (stimulation or packing in the superior zone and packing in the inferior zone), reducing the number of pipe trips in each well and therefore, reducing the operational risks and drilling costs. This type of completion will also allow independent isolation in anyone of the zones in the event of watering problems, allowing selective production.In all the cases, successful gravel packing were achieved as well as 45% saving in drilling time, compared with conventional completion. In all the cases productivity was higher than the initial estimate, without formation sand production, confirming the success of the application.This technology provides a reliable and profitable alternative for the completion of two or three simultaneous zones.

Sand production is a well-known and costly problem in shallow unconsolidated sands. For years slotted liners have been used to control sand in these types of reservoirs. However, over time sand, fines and other debris can clog slots or make their way into the liner itself, thus blocking production. A new live-well intervention technique making use of a concentric coiled tubing (CCT) vacuum tool (VT) has been implemented in Venezuela1,2,3. The technique incorporates a venturi jet pump mounted on CCT, and is specifically designed to remove solids and/or fluids from the wellbore without placing hydrostatic loads on the reservoir. In sand vacuum mode, strong jets fluidize and mobilize solids into the vacuum as well as prevent a stuck pipe scenario. The jets also aid in opening clogged slots by loosening fines that may be blocking flow. When the VT applies suction, a localised pressure-influenced-zone is formed in the very near wellbore – thus providing an isolated ";point-load"; drawdown on the formation. The jetting action combined with point-load drawdown and drag forces results in solids removal from behind pipe as well as inside pipe. Evidence of this phenomenon are jobs where a solids volume greater than the entire liner has been retrieved to surface. Post job results on jobs performed in Venezuela consistently show reduced skin, increased Productivity Index (PI) and higher long-term oil production. This paper describes the latest in CCT vacuum technology as well as it improvement in time via case studies of several different applications in Venezuela. Also discussed are simple lab techniques, which reveal serious completion issues such as liner slot erosion, fines invasion and drilling fluid damage.

Anti-inflammatory potentials of a safe, common dietary component, quercetin, were investigated in suppression of intraocular inflammation induced by retinal S antigen. Lewis rats sensitized to S antigen were treated daily with intraperitoneal injections of quercetin. Control rats with S-antigen-induced uveitis were similarly treated with diluent. When compared with controls the treated group showed marked reduction in uveal and retinal inflammation and in vasculitis and perivasculitis. Morphometric analysis revealed a significant reduction (p less than 0.005) in choroidal thickness when compared with that of control animals. These results clearly show the antiphlogistic effects of quercetin in experimental uveitis.

Modulation of signal transduction at the surface of inflammatory cells appears to influence acute inflammation. Adenosine, a well-known chemical messenger, inhibits the production of superoxide by sti

Dimethyl thiourea is a highly specific hydroxyl radical scavenger. The anti inflammatory potential of this hydroxyl radical scavenger was studied in Lewis rats sensitized with soluble lens protein. Intraperitoneal injection of dimethyl thiourea into the experimental animals at the onset of the disease resulted in marked reduction of intraocular inflammation, hemorrhage and edema, and eliminated the retinal and choroidal necrotizing vasculitis that was characteristic in untreated animals. These findings indicate that dimethyl thiourea may act as a potent antiphlogistic agent in the treatment of experimental lens induced uveitis.

In acute inflammation, the tissue damage is generally mediated through polymorphonuclear leukocytes and macrophages. Recent studies on the mechanism of this leukocyte-mediated cytolysis have demonstrated that these cells, on stimulation, release a variety of reactive products. These metabolic products consist of superoxide and hydrogen peroxide, which in turn can form highly reactive species such as hydroxyl radicals. It is believed that these oxygen products play an important role in the tissue damage that occurs in inflammations such as uveitis. The ocular structures contain various antioxidant enzymes that normally protect against free radical mediated injury. In experimental animal models of uveitis, it has been shown that antioxidants and free radical scavengers can function as antiinflammatory agents and can protect the eye from inflammation-mediated tissue damage.

An acute lens-induced necrotizing intraocular inflammation was produced in Lewis rats. Treatment of these animals by intraperitoneal injection of glutathione peroxidase resulted in marked decrease in uveal inflammation, retinal edema, hemorrhage and vasculitis. Intraperitoneal injection of glutathione peroxidase resulted in increased levels of this enzyme in ocular tissue. These findings suggest that glutathione peroxidase can modulate acute lens-induced ocular inflammation by serving as a potent anti-inflammatory agent.

• A patient with keratoconus who could not tolerate a contact lens underwent electrosurgical keratoplasty. Postoperatively, the central cornea was markedly flattened, but five weeks later the central steepening had recurred. Six months after the procedure, a penetrating keratoplasty was performed. Pathologic examination of the corneal button revealed an intact epithelium and basement membrane. Bowman's membrane was completely destroyed in the treated areas. Stromal scarring extended to involve the anterior two thirds of the corneal stroma. The collagen in this area was contracted and folded. The keratocytes and stromal collagen of the posterior third of the cornea were normal by light microscopy. Descemet's membrane and the endothelium also were normal. Despite the short-lived flattening of corneal topography, this procedure dramatically altered the stromal collagen in the anterior two thirds of the cornea.

• Lewis rats with retinal S-antigeninduced uveitis were treated with the enzymatic antioxidants superoxide dismutase and catalase or with the hydroxyl radical scavenger dimethyl thiourea for one week. The enucleated eyes of these animals and of normal saline-treated control rats were studied for the presence of lipid peroxidation products in the retina; in addition, choroidal thickness was measured by morphometric analysis to determine the severity of choroidal inflammation. Control animals showed severe chorioretinal inflammation and presence of lipid peroxidation products. Intraocular inflammation was less severe and formation of conjugated dienes and malonaldehyde was significantly inhibited in animals treated with the enzyme antioxidants or dimethyl thiourea. These results suggest that free radicals generated during intraocular inflammation can lead to retinal damage by peroxidation of its lipid cell membranes.

A 41-year-old man receiving long-term immunosuppressive therapy after renal transplantation developed progressive ulcerative lesions involving both lower eyelids. The lesions began as crusting and exfoliating masses and developed over a one-year period. A biopsy demonstrated that the lesions were invasive squamous cell carcinomas.

Bacterial membranes present solid-ordered/liquid-disordered (so/ld) cooperative melting event close to physiological temperature. The cellular advantage of this thermotropic melting event is yet to be determined. We show that this thermal behavior provides resistance towards a membrane active antibacterial agent.Phospholipase A2 type IIA (sPLA2-IIA) is a hydrolytic enzyme which presents antibacterial properties towards Gram positive bacteria. The enzyme has higher activity in ld phase compared to so phase in anionic membranes. We show that the lipid phase behavior of Staphylococcus aureus (S.aureus) membranes as measured by FTIR modulates sPLA2-IIA by inducing a sharp drop in activity below the melting temperature of the membrane (centered at 15.3°C).The effects of sPLA2-IIA treatment on cell viability are also investigated. While above the main melting event viability drops to 20% of the initial CFU after treatment, below the main melting event cell viability only drops to 60% under the same treatment. This strongly suggests that cells in the solid-ordered phase are better adapted to survive the enzymatic insult.These results led us to explore if a subpopulation of S.aureus enriched in ordered lipids can be selected after repeated treatment with sPLA2-IIA at 37°C. After selecting for resistance at 37°C we measured growth curves, membrane order, and cell viability as a function of treatment temperature. The results suggest that at 37°C there is a bacterial subpopulation with increased membrane rigidity that insures survival of the colony to an insult by sPLA2-IIA. This subpopulation also presents a longer latency period which can be explained by the increased presence in ordered lipids, which are known to inhibit cell division. Even if the growth conditions are not optimal, the presence of this subpopulation ensures survival from the antibacterial insult.