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A wide range of indirect data obtained during the last two decades has suggested that monoamine neurons may co-release neurotransmitters. Ultrastructural investigations have consistently reported that these neurons, including dopamine, serotonin and norepinephrine neurons establish both junctional (i.e. synaptic) and non-junctional (i.e. non-synaptic) axon terminals. The hypothesis that some of these terminals can mediate synaptic glutamate release has received strong support from cell culture studies as well as indirect support from electrophysiological recordings obtained in slice preparations and in intact animals. The molecular identification of vesicular glutamate transporters (VGluTs) in recent years has provided a new impetus and a new strategy to confirm the glutamatergic phenotype of neurons. A number of recent results now confirm that while many serotonin neurons express VGluT3, a subset of norepinephrine and dopamine neurons express VGluT2, thus supporting the hypothesis of glutamate co-transmission. The possibility that the neurotransmitter repertoire of central monoamine neurons may be plastic during development and in the context of activity-dependent neuronal plasticity or disease is now a major direction of current research.

There is increasing evidence that a subset of midbrain dopamine (DA) neurons uses glutamate as a co-transmitter and expresses vesicular glutamate transporter (VGLUT) 2, one of the three vesicular glutamate transporters. In the present study, double in situ hybridization was used to examine tyrosine hydroxylase (TH) and VGLUT2 mRNA expression during the embryonic development of these neurons, and postnatally, in normal rats and rats injected with 6-hydroxydopamine (6-OHDA) at P4 to destroy partially DA neurons. At embryonic days 15 and 16, there was a regional overlap in the labeling of TH and VGLUT2 mRNA in the ventral mesencephalon, which was no longer found at late embryonic stages (E18–E21) and postnatally. In normal pups from P5 to P15, only 1–2% of neurons containing TH mRNA in the ventral tegmental area (VTA) and substantia nigra, pars compacta, also displayed VGLUT2 mRNA. In contrast, after the cerebroventricular administration of 6-OHDA at P4, 26% of surviving DA neurons in the VTA of P15 rats expressed VGLUT2. To search for a colocalization of TH and VGLUT2 protein in axon terminals of these neurons, the nucleus accumbens of normal and 6-OHDA-lesioned P15 rats was examined by electron microscopy after dual immunocytochemical labeling. In normal rats, VGLUT2 protein was found in 28% of TH positive axon terminals in the core of nucleus accumbens. In 6-OHDA-lesioned rats, the total number of TH positive terminals was considerably reduced, and yet the proportion also displaying VGLUT2 immunoreactivity was modestly but significantly increased (37%). These results lead to the suggestion that the glutamatergic phenotype of a VTA DA neurons is highly plastic, repressed toward the end of normal embryonic development, and derepressed postnatally following injury. They also support the hypothesis of co-release of glutamate and DA by mesencephalic neurons in vivo , at least in the developing brain.

This reference is for an abstract only. A full paper was not submitted for this conference. Abstract A new stimulation technique of limestone and dolomite wells has been successfully implemented in several regions around the world (South America, Europe, Middle East, and South East Asia), since 2005. The technique consists on creating multiple drainage holes across the pay zone. The holes are created by pumping chloridric acid (HCl) through a specially designed jetting bottom assembly, deploying standard coiled tubing and pumping equipment. The purpose of these drainage holes is to improve the connectivity between ther reservoir and the wellbore, and positively impact well production. This technique is applicable on carbonate wells with relatively thick pay zones, and barefoot completions. One can create as many drainage holes as required, at different depths. The depth selections are based on key indicators. Among the most important are available logs (image, resistivity, caliper, drilling…), and observed lost circulation zones while drilling. Results of this new stimulation technique on barefoot carbonate wells have been superior in areas where they were compared against conventional acid work (matrix acidizing, plane acid jetting with coiled tubing, and acid fracing). Several case histories from different regions of the world, stimulation design criteria, operational procedures, and results are included in this paper. As over 60% of the world's reserves and production come from carbonates, this technique brings a new benchmark in well stimulation of barefoot limestone and dolomite wells.

There is solid electron microscopic data demonstrating the existence of dopamine (DA) axon terminals (varicosities) with or without synaptic membrane specializations (junctional complexes) in many parts of the CNS, and notably in neostriatum and nucleus accumbens. The dual morphological character of these DA innervations has led to the suggestion that the meso-telencephalic DA system operates by diffuse (or volume) as well as by classical synaptic transmission. In the last decade, electrophysiological and neurochemical evidence has also accumulated indicating that monoamine neurons in various parts of the CNS, and particularly the mesencephalic DA neurons, might release glutamate as a co-transmitter. Following the identification of the vesicular transporters for glutamate (VGluT), in situ hybridization and RT-PCR studies carried out on isolated neurons or standard tissue cultures, and more recently in vivo, have shown that VGluT2 mRNA may be expressed in a significant proportion of mesencephalic DA neurons, at least in the ventral tegmental area. A current study also suggests that the co-expression of tyrosine hydroxylase (TH) and VGluT2 by these neurons is regulated during embryonic development, and may be derepressed or reactivated postnatally following their partial destruction by neonatal administration of 6-hydroxydopamine (6-OHDA). In both 15 day-old and adult rats subjected or not to the neonatal 6-OHDA lesion, concurrent electron microscopic examination of the nucleus accumbens after dual immunocytochemical labeling for TH and VGluT2 reveals the co-existence of the two proteins in a significant proportion of these axon terminals. Moreover, all TH varicosities which co-localize VGluT2 are synaptic, as if there was a link between the potential of DA axon terminals to release glutamate and their establishment of synaptic junctions. Together with the RT-PCR and in situ hybridization data demonstrating the co-localization of TH and VGluT2 mRNA in mesencephalic neurons of the VTA, these observations raise a number of fundamental questions regarding the functioning of the meso-telencephalic DA system in healthy or diseased brain.

This paper provides a case history of the first hydraulic fracture on a subsea horizontal well in the Quissamã formation, a low permeability limestone reservoir, in Campos Basin, Brazil. The well was drilled in the direction of the expected fracture growth, thus evolving longitudinal fractures along the horizontal section. It is part of a research project to evaluate selective stimulation methods for subsea horizontal wells. Every single aspect since the drilling, completion, and evaluation of the well, was done with the end in mind of hydraulically fracturing it in several stages. Hydraulically fracturing a horizontal well has become a more accepted practice in our industry. The procedures used on fracturing of vertical wells must be taken into consideration when fracturing a horizontal well, to avoid re-fracturing work. Near-wellbore (NWB) problems are usually the main cause why fracturing work are not completed. This paper describes hydraulic fracture treatments with detailed discussion on analysis of calibration tests, fluid efficiency tests, and lessons learned. Results of the pumping work will be presented showing theory and common practices played a key role for a successful application of techniques used. Laboratory tests are presented performed with cores taken from the well itself such, as rock mechanics, proppant embedment, compactation measurements, and basic mineralogy. Production results will be presented and compared to conventional methods used on other subsea horizontal completed wells in Campos Basin.

When gravel packing horizontal wells, operators usually deploy conventional, and commercially available gravel pack proppants in the industry. Several jobs have been successfully completed up to date with no considerable concerns. However, under certain unfavorable conditions, a better option to gravel pack these wells is ultra-lightweight proppants.Deepwater well, extended reach horizontals, low fracture gradients, washed out zones, and insufficient fluid returns to circulate conventional proppant in place are good examples where lighter weight proppant is needed to assure the complete packing of the open hole.This paper summarizes the development and application of the ultra-lightweight media and associated technologies for horizontal well gravel packing. Pioneering case histories will also be reviewed from the initial wells treated. The wells were completed on a field in the Campos Basin, offshore Brazil, where the reservoirs are sandstones, highly unconsolidated and therefore require a method of sand control.

In offshore horizontally completed wells, an acid job is usually pumped to remove the filter cake, previously created to allow sand control equipment and gravel be placed across the entire extended section. When such wells are acidized to remove the filter cake with a hydrochloric: hydrofluoric acid mixture, the resulting skin values are still in the positive range. An improved HF acid system has been introduced in the Campos Basin-offshore Brazil with outstanding results. The HF acid system uses an organophosphonic acid complex to control the generation of HF and to dramatically reduce potentially damaging secondary and tertiary precipitates. This paper describes the results of field treatments showing truly stimulated wells with negative skins - a first in this Campos Basin field for deepwater horizontal wells. Case histories with conventional regular hydrochloric: hydrofluoric acid mixture and with the improved acid system used will be presented. Laboratory core flow tests were performed in advance of the field program with seven different acid blends.Only one acid blend resulted in complete mud damage removal and true stimulation. Innovative equipment design, a state-of-the-art vessel with real-time monitoring capabilities, improved placement techniques and environmentally-friendly materials, are helping to transform acidizing into a valuable method in the quest for optimum performance from every injector, oil and gas well asset.

Proposal Horizontal gravel packs typically employ heavy sand or ceramic gravels, laid down with un-gelled brines in the well-known alpha/beta wave sequence.As operators push the limits of horizontal open hole interval lengths, especially in low fracture gradient formations, it may become technically difficult or economically unfeasible to perform the gravel pack with conventional fluids and gravels. Ultra lightweight gravels allow significant reductions in pumping rate (to avoid fracturing the formation), without risking premature settling and screen-out, therefore, longer wells can be treated.Higher gravel concentrations can also be used, even at low pump rates, resulting in drastic reductions in fluid volumes and treatment time, which is critical in cost-intensive offshore applications.In certain instances, the alpha wave can be eliminated, and the well packed directly in the beta wave mode, from toe to heel. This paper summarizes the development and application of the ultra lightweight media and associated technologies for horizontal well gravel packing.Pioneering case histories will also be reviewed from the initial wells treated.

The economics of the oil and gas production requirements and advanceddrilling technologies are often pushing the length of horizontal well to newrecords. Gravel packing these very long horizontal wells present new challengesto completion operations. The combination of long horizontal sections ofunconsolidated formations, low fracture gradients and costly rig time are theother constraints that must be faced in the design and execution of asuccessful gravel packing completion offshore. Innovative technologies, optimized job design and planning are the keys for the success of packingjobs.This paper addresses several key factors that must be considered carefullyin installing a successful gravel pack completion. Pack completion requiresthat these low fracture gradient wells not be fractured during gravel placementto avoid excess leakoff and premature screenouts. The discussion includesvarious measures such as optimized screen wash pipe annulus and appropriateusing the differential valves, to effectively reduce frictional pressure duringBeta wave buildup. Fluid leakoff and leakoff control, in-situ gravelconcentration, and their relationship are also discussed. The gravelconcentration is dynamically changing through out the treatment based on theflow conditions in the wellbore, especially when the gravel starts to packaround screen. While most of the fluid travels down the screen-casing annulus, portion of the fluid leaks into formation, portion of the fluid diverges intothe screen-wash pipe annulus. The results may be an effective in-situ gravelconcentration higher than critical concentration, forcing gravel particledeposition to occur too soon and building up a premature bridge.Several job designs and application histories are also presented in thepaper to demonstrate the design considerations and valuable lessons learnt. Agroup of type curves are generated for a quick and easy check during joboperation, if any undesired condition is present, the operator can adjust theoperation and thus to avoid a job failure. The overall system of fluid dynamicsare discussed and treatment guidelines are presented to provide the CompletionEngineers the necessary information for designing successful treatments.

This article is concerned with convergencies and radiations of the family and household structures in Guatemalan society and their possible relation to sub-cultural styles and personality types. Survey procedures with formal analytical devices are combined in an effort to supersede methodological difficulties making compatible the analysis and quantification of a large number of cases with a systemic view of the family. Kinship, consanguinity-affinity, lineality-collaterality, and generation are used as structural variables in the description, analysis, and comparison of the families of the five major social segments of Guatemalan society. These segments are: Traditional and Modified Indians, Rural Ladino (nonIndian) and Low, Middle, and High Urban. Comparisons across stages of the household-family cycle were made possible by the subdivision of the total 1,105 family sample into two comparable sub-samples defined by the age of the female head of the household. The results obtained contradict a variety of misconceptions and prejudices regarding the family in various social segments including the Traditional Indian and the Middle Urban, and they may provide a useful platform for gaining a better understanding of how Guatemalan society is assembled and works, and for identifying sources of tension and conflict within it.

Cultural behavior, when viewed as an extrasomatic adaptation for humans, alters previous interpretations of taboos as harmless placations of the supernatural. If the adaptive premise is true, then one may expect to find that taboos either have, or at one time had, an adaptive significance. This paper examines the salt and salt-containing-food taboos that were prevalent among the Indians in the southeastern United States during the early historic period. The analysis indicates that salt taboos existed as a means of regulating dietary sodium intake at times when such control was crucial for the restoration of biological equilibrium. Salt taboos occurred when a low-sodium diet would be physically advantageous: during menstruation, pregnancy, some diseases, and mourning. Prohibitions aloso applied where the behavior resulting from the disrupted system was considered desirable by the cultures concerned: during puberty rites and warfare.

Young subjects’ beliefs in God, the Virgin Mary and the Devil are analyzed in terms of their structural situation in their families. Family structure is seen as a set of principles (generation, sex and age), that assign rights and duties, and which, combined, determine positions, such as ‘first generation, male, older’. A given position is equivalent to, or different from one or more other positions when one principle alone, for instance, sex is considered. Symbolic preferences expressed in frequency and intensity of belief are examined as manifestations of claims and recognitions derived from these principles and the avenues they create for identification with other positions. In addition to ego’s structural position, the actual presence or absence of individuals in other structural positions in a given family seems to be an important factor: different forms and intensities of conflict (structural disjunction) can result from similar claims made from two different positions. Four situations are accordingly differentiated; ego’s conceptualization of the religious entities and his belief in them are analyzed within the frame of these situations. More generally, the study tries to differentiate between symbols which express the total structural position of a segment or unit, self identity, or a feeling of collectivity among members, and those which express only the structural unity of otherwise heterogeneous segments. This is a preliminary report based on a larger study; the data presented is based on individual interviews with 59 non-Indian male subjects 10 to 18 years old. Brief comparisons are drawn between these and results from a comparable Indian sample.

This paper describes a field example of Planning to frac tight Shaly sand formation which offers a unique challenge for fluids, equipment and personnel. The main objective is to maximize the value of the field over its productive lifetime. The primary benefit from these applications is the utilization of the equipment capabilities and the fluids properties to get the best possible fracture length and conductivity for optimizing field-development economics. The objective of the paper is to make available the information needed to do the proper preparation and execution for similar well conditions in the area. Starting with the proper field study to have the best candidate for the hydraulic fracturing was a key parameter for the success of the job. This field has started with initial pressure of 2400 psi and total potential of 7000 BOPD. Other consideration concerning the lithology characteristic of the reservoir, the tight shaly sand formation will not produce at its best potential without the high pressure proppant frac. The selection of the fluid suitable for this job was mainly to have to best properties and stable fluid to carry the proppant, not damaging to the formation, not to cause any clay swelling, easy to X-Link and easy to break after the job. Also the selection of the equipments to give the proper rate and pressure with fully remote control from the data van was considered to have a successful job.