bluuebunny/crossref_metadata_2025 huggingface dataset:
Formal Contracts in the Presence of Relational Enforcement Mechanisms: Evidence from Technology Development Projects
Authors: Ryall Michael D. , Sampson Rachelle C.
Published: March 2009

Formal contracting addresses the moral hazard problems inherent in interfirm deals via explicit terms designed to achieve incentive alignment. Alternatively, when firms expect to interact repeatedly, relational mechanisms may achieve similar results without the associated costs. However, as we now know from a growing body of theoretical and empirical work, the resulting intuition—that relational mechanisms will be substituted for formal ones whenever possible—does not generally hold. The extent to which firms substitute relational mechanisms for formal ones in the presence of repeated interaction is an empirical question that forms the basis of this paper. We study a sample of 52 joint technology development contracts in the telecommunications and microelectronics industries and devise a coding scheme to allow empirical comparison of contract terms. Counter to the above intuition (but consistent with recent research), we find that a firm's contracts are more detailed and more likely to include penalties when it engages in frequent deals (whether with the same or different partners). Our results suggest complementarity between formal and relational contracts, and have implications for optimal contracting, particularly in high technology sectors.
Effect of manipulated prestige‐car ownership on both sex attractiveness ratings
Authors: Dunn Michael J. , Searle Robert
Published: March 2009

Previous studies have shown that male attractiveness can be enhanced by manipulation of status through, for example, the medium of costume. The present study experimentally manipulated status by seating the same target model (male and female matched for attractiveness) expressing identical facial expressions and posture in either a ‘high status’ (Silver Bentley Continental GT) or a ‘neutral status’ (Red Ford Fiesta ST) motor‐car. A between‐subjects design was used whereby the above photographic images were presented to male and female participants for attractiveness rating. Results showed that the male target model was rated as significantly more attractive on a rating scale of 1–10 when presented to female participants in the high compared to the neutral status context. Males were not influenced by status manipulation, as there was no significant difference between attractiveness ratings for the female seated in the high compared to the neutral condition. It would appear that despite a noticeable increase in female ownership of prestige/luxury cars over recent years males, unlike females remain oblivious to such cues in matters pertaining to opposite‐sex attraction. These findings support the results of previous status enhancement of attractiveness studies especially those espousing sex differences in mate preferences are due to sex‐specific adaptations.
Interpersonal complementarity in responses to auditory hallucinations in psychosis
Authors: Thomas Neil , McLeod Hamish J. , Brewin Chris R.
Published: March 2009

Objectives. Models of interpersonal relating have proposed that people are drawn to respond to others according to a principle of complementarity, whereby perceived hostility elicits reciprocal hostility and perceived dominance elicits submission. This study examined interpersonal appraisals and responses to auditory hallucinations, to determine whether this principle predicts how patients respond to hallucinated voices.

Design and methods. Thirty‐five participants with schizophrenia or schizoaffective disorder rated their internal ‘relationship’ with their auditory verbal hallucinations using the Structural Analysis of Social Behaviour, in addition to completing measures of voice‐related distress and depression.

Results. Participants were able to ascribe almost the full range of interpersonal relating behaviours to their voices reliably, with some notable exceptions for voices' ‘responses’ to being directly addressed. Appraisals of voice hostility very strongly predicted reciprocal hostile responses, but perceptions of voice control were only weakly associated with submission to voices. Perceived voice hostility was also associated with voice‐related distress and perceived voice control was associated with depression.

Conclusions. Individual differences in responses to auditory hallucinations appear to reflect normal interpersonal responses to appraisals of voice hostility and affiliation. However, voice hearers do not readily submit to voice control and other factors may be of importance in determining this response.
Elaborating the cry of pain model of suicidality: Testing a psychological model in a sample of first‐time and repeat self‐harm patients
Authors: Rasmussen Susan A. , Fraser Louisa , Gotz Michael , MacHale Siobhan , Mackie Rhona , Masterton George , McConachie Susan , O'Connor Rory C.
Published: March 2009

Objectives. Few studies have specifically tested the Cry of Pain model (CoP model; Williams, 2001). This model conceptualizes suicidal behaviour as a behavioural response to a stressful situation which has three components: defeat, no escape potential, and no rescue. In addition, the model specifies a mediating role for entrapment on the defeat–suicidal ideation relationship, and a moderating role for rescue factors on the entrapment–suicidal ideation relationship. This is the first study to investigate the utility of this psychological model in a sample of first‐time and repeat self‐harm (SH) patients.

Method. One hundred and thirteen patients who had been admitted to hospital following an episode of SH (36 first‐time, 67 repeat) and 37 hospital controls completed measures of defeat, entrapment/escape potential, rescue (social support and positive future thinking), as well as depression, anxiety, and suicidal ideation.

Results. Analyses highlighted differences between the three participant groups on all of the CoP variables. Hierarchical regression analysis confirmed that total entrapment and internal entrapment mediated the relationship between defeat and suicidal ideation, whilst impaired ability to think positively about the future (but not social support) moderated the relationship between total and internal entrapment and suicidal ideation.

Conclusions. The findings provide further empirical support for the CoP Model. The findings are discussed in relation to theory and practice and we recommend that the findings are replicated within a prospective design.
Imagining intergroup contact reduces implicit prejudice
Authors: Turner Rhiannon N. , Crisp Richard J.
Published: March 2009

Recent research has demonstrated that imagining intergroup contact can be sufficient to reduce explicit prejudice directed towards out‐groups. In this research, we examined the impact of contact‐related mental imagery on implicit prejudice as measured by the implicit association test. We found that, relative to a control condition, young participants who imagined talking to an elderly stranger subsequently showed more positive implicit attitudes towards elderly people in general. In a second study, we demonstrated that, relative to a control condition, non‐Muslim participants who imagined talking to a Muslim stranger subsequently showed more positive implicit attitudes towards Muslims in general. We discuss the implications of these findings for furthering the application of indirect contact strategies aimed at improving intergroup relations.
The Weight of the Sword of Damocles: A Reconviction Analysis of Suspended Sentences in Tasmania
Authors: Bartels Lorana
Published: March 2009

Suspended sentences are a widely used but controversial sentencing disposition. This article presents reconviction rates for all sentences imposed over a 2-year period in the Tasmanian Supreme Court, as well as examining different outcomes on the basis of key sentencing variables, including offence type and prior record. The results demonstrate that suspended sentences have comparatively low reconviction rates. The study examines the relative frequency and seriousness of offending, thereby overcoming a common criticism of reconviction studies that they are an ‘all-or-nothing’ measure, which does not take into account changes in offending patterns. The study also avoids the common error of misattributing reconviction rates to incidences of offending that occurred prior to the imposition of the relevant sentence by excluding pseudoreconvictions, and the findings indicate the extent to which pseudoreconvictions can skew reconviction results. In addition, the use of suspended sentences in combination with other orders, and the reconviction outcomes of such sentences, is analysed. The article concludes with a discussion of the implications of my findings for the further use of suspended sentences, and for future research.
Symposium on Materials Research Frontiers
Authors: ASTM Administrative Committee  , New England District Council Committee
Published: March 2009

Description

Five papers include: Materials in the Nuclear Age; Modern Liquid Fuels; Recent Developments in Glass Research; Tailoring the Properties of Materials; Molecular Engineering
Symposium on Stability of Distillate Fuel Oils
Authors: ASTM Committee D-2
Published: March 2009

Description

Eight papers include stability, measurement, incompatibility of fuels, tests for stability, requirements, gels, burner nozzles, and general problem reviews.
Light Scattering Instrumentation for Particle Size Distribution Measurements
Authors: O'Konski CT , Bitron MD , Higuchi WI
Published: March 2009

An improved instrument is described for the characterization of particles suspended in gases by means of light scattering. It consists of (1) a sensitive right-angle optical system with a photomultiplier detector, (2) a coaxial flow system which facilitates variation of the particle concentration range, (3) a photometer which continuously records the average light scattering signal, and (4) a pulse analyzer for size discrimination of individual particles. The particle analyzer was calibrated with uniform polystyrene spheres from a 0.33 to 1.17 μ in diameter, employing air as a scattering standard. The scattering intensity was found to be approximately proportional to the square of the diameter. Resolving power was determined as a function of particle size, and the instrument was critically evaluated. A brief review of particle detectors is given. A versatile pulse height selector system is described. Some variations of the instrument are proposed.
Association of the IGF1/pregnancy-associated plasma protein-A system and adipocytokine levels with the presence and the morphology of carotid plaques in type 2 diabetes mellitus patients with stable glycaemic control
Authors: Pellitero Silvia , Reverter Jordi L , Granada María Luisa , Pizarro Eduarda , Pastor M Cruz , Tàssies Dolors , Reverter Juan Carlos , Salinas Isabel , Sanmartí Anna
Published: March 2009

Objective

Pregnancy-associated plasma protein-A (PAPP-A) has been implicated in the atherosclerotic process through regulation of local expression of IGF1. In type 2 diabetes mellitus, glycaemic control has been involved in PAPP-A expression. We compared PAPP-A, IGF1, inflammatory markers and adiponectin concentrations in type 2 diabetic patients with and without carotid plaques and evaluated the relationship between these serum parameters and ultrasound carotid markers of atherosclerosis.

Methods

We studied 125 consecutive type 2 diabetic patients. Clinical data, metabolic variables, hemostatic factors (plasma type-1 plasminogen activator inhibitor, fibrinogen), high-ultrasensitive C reactive protein (hsCRP), tumor necrosis factor (TNF)-α, interleukin (IL)-6, adiponectin, IGF1 and PAPP-A were determined. Patients were classified into two groups according to the presence of carotid plaques on ultrasound. Carotid intima–media thickness (IMT) and morphology of carotid plaques were evaluated.

Results

The mean age was 61.5±7.3 years and the mean glycated hemoglobin of 6.8±0.9%. A total of 60% presented carotid plaques. Both groups were homogeneous in anthropometric data, biochemical determinations and hemostatic factors. Adiponectin, hsCRP, TNF-α and IL-6 were similar in both groups. No differences were observed in serum PAPP-A (0.46 (0.22–0.86) vs 0.38 (0.18–0.66) mIU/l and in SDS IGF1 (−0.34±1.38 vs −0.67±1.35)) in patients with and without carotid plaques respectively. PAPP-A and IGF1 were not correlated with IMT.

Conclusions

Serum PAPP-A and IGF1 do not appear to be useful serum biomarkers for carotid atherosclerosis in type 2 diabetic patients with stable glycemic control, despite scientific evidence of their local role in atherosclerosis.
The role of estrogens for male bone health
Authors: Ohlsson Claes , Vandenput Liesbeth
Published: March 2009

Sex steroids are important for the growth and maintenance of both the female and the male skeleton. However, the relative contribution of androgens versus estrogens in the regulation of the male skeleton is unclear. Experiments using mice with inactivated sex steroid receptors demonstrated that both activation of the estrogen receptor (ER)α and activation of the androgen receptor result in a stimulatory effect on both the cortical and trabecular bone mass in males. ERβ is of no importance for the skeleton in male mice while it modulates the ERα-action on bone in female mice. Previous in vitro studies suggest that the membrane G protein-coupled receptor GPR30 also might be a functional ER. Our in vivo analyses of GPR30-inactivated mice revealed no function of GPR30 for estrogen-mediated effects on bone mass but it is required for normal regulation of the growth plate and estrogen-mediated insulin-secretion. Recent clinical evidence suggests that a threshold exists for estrogen effects on bone in men: rates of bone loss and fracture risk seem to be the highest in men with estradiol levels below this threshold. Taken together, even though these findings do not exclude an important role for testosterone in male skeletal homeostasis, it is now well-established that estrogens are important regulators of bone health in men.
Patterns of Intraspecific DNA Variation in the Daphnia Nuclear Genome
Authors: Omilian Angela R , Lynch Michael
Published: March 2009

Understanding nucleotide variation in natural populations has been a subject of great interest for decades. However, many taxonomic groups, especially those with atypical life history attributes remain unstudied, and Drosophila is the only arthropod genus for which DNA polymorphism data are presently abundant. As a result of the recent release of the complete genome sequence and a wide variety of new genomic resources, the Daphnia system is quickly becoming a promising new avenue for expanding our knowledge of nucleotide variation in natural populations. Here, we examine nucleotide variation in six protein-coding loci for Daphnia pulex and its congeners with particular emphasis on D. pulicaria, the closest extant relative of D. pulex. Levels of synonymous intraspecific variation, πs, averaged 0.0136 for species in the Daphnia genus, and are slightly lower than most prior estimates in invertebrates. Tests of neutrality indicated that segregating variation conforms to neutral model expectations for the loci that we examined in most species, while Ka/Ks ratios revealed strong purifying selection. Using a full maximum-likelihood coalescent-based method, the ratio of the recombination rate to the mutation rate (c/u), averaged 0.5255 for species of the Daphnia genus. Lastly, a divergence population-genetics approach was used to investigate gene flow and divergence between D. pulex and D. pulicaria.
Utilização dos registros de dispensação da farmácia como indicador da não-adesão à terapia anti-retroviral em indivíduos infectados pelo HIV
Authors: Gomes Raquel Regina de Freitas Magalhães , Machado Carla Jorge , Acurcio Francisco de Assis , Guimarães Mark Drew Crosland
Published: March 2009

Este estudo teve como objetivos avaliar os registros de dispensação de anti-retrovirais (ARV) por um período de 12 meses após a primeira prescrição e determinar os fatores associados com a retirada irregular ou abandono em dois serviços públicos de referência para AIDS, em Belo Horizonte, Minas Gerais, Brasil. Participaram 323 pacientes infectados pelo HIV, virgens de tratamento, recrutados entre maio de 2001 e maio de 2002. No período, 98 (30,3%) pacientes abandonaram a terapia e 187 (57,9%) tiveram pelo menos uma retirada irregular. Indivíduos com retirada irregular ou que abandonaram a terapia foram comparados àqueles com retirada regular. Análise multivariada multinomial indicou que morar fora de Belo Horizonte, ter contagem de linfócitos TCD4+ maior que 200 células/mm³ e uso de esquema sem inibidor de protease estavam associados com retirada irregular. Além dessas variáveis, o abandono mostrou associação com não fazer uso de outra medicação e ter registro de não-adesão no prontuário médico. Os registros da farmácia destacaram-se como potencial indicador de não-adesão, devendo ser incorporados à prática clínica. Ações que busquem os pacientes ausentes ou com retirada irregular devem ser priorizadas.
Fatores associados à duração do aleitamento materno em crianças de famílias de baixa renda da região sul da cidade de Curitiba, Paraná, Brasil
Authors: Baptista Gerson Henrique , Andrade Adriano Herbert H. K. Gonçalves de , Giolo Suely Ruiz
Published: March 2009

O aleitamento materno e os possíveis fatores associados ao desmame precoce têm sido alvos de diversos estudos. Este trabalho teve como objetivo identificar, em famílias de baixa renda da região sul de Curitiba, Paraná, Brasil, fatores de risco ou de proteção associados à duração do aleitamento materno. Um estudo de coorte foi conduzido entre novembro de 2006 e março de 2007 com 118 mães de crianças menores de dois anos de idade com vínculo na Unidade de Saúde TC (USTC), localizada na região sul de Curitiba. Análises estatísticas realizadas com o auxílio do método de Kaplan-Meier e do modelo de regressão de Cox apontaram como fatores protetores do aleitamento materno: a consciência da mãe sobre os benefícios da amamentação por tempo estendido, a amamentação da criança com leite exclusivamente materno na maternidade e o alojamento conjunto da mãe e criança na maternidade. Por outro lado, o baixo peso da criança ao nascimento, o trabalho da mãe fora de casa e as dificuldades encontradas pela mãe para amamentar nos primeiros dias pós-parto foram fatores apontados como contribuidores do desmame precoce.
Structural and functional multiplicity of the kisspeptin/GPR54 system in goldfish (Carassius auratus)
Authors: Li Shuisheng , Zhang Yong , Liu Yun , Huang Xigui , Huang Weiren , Lu Danqi , Zhu Pei , Shi Yu , Cheng Christopher H K , Liu Xiaochun , Lin Haoran
Published: March 2009

To ascertain the neuroendocrine function of the kisspeptin/GPR54 system in non-mammalian species, full-length cDNAs encoding for Kiss1 and Kiss2 as well as their putative cognate receptors GPR54a and GPR54b, were isolated from goldfish (Carassius auratus). The deduced protein sequences between Kiss1 and Kiss2 in goldfish share very low similarity, but their putative mature peptides (kisspeptin-10) are relatively conserved. RT-PCR analysis demonstrated that the goldfish kiss1 gene (gfkiss1) is highly expressed in the optic tectum-thalamus, intestine, kidney, and testis, while the goldfish kiss2 gene (gfkiss2) is mainly detected in the hypothalamus, telencephalon, optic tectum thalamus, adipose tissue, kidney, heart, and gonads. The two receptor genes (gfgpr54a and gfgpr54b) are highly expressed in the brain regions including telencephalon, optic tectum thalamus, and hypothalamus. Both mature goldfish kisspeptin-10 peptides (gfKiss1–10 and gfKiss2–10) are biologically active as they could functionally interact with the two goldfish receptors expressed in cultured eukaryotic cells to trigger the downstream signaling pathways with different potencies. The actions of gfKiss1–10 and gfKiss2–10 on LH secretion were further investigated in vitro and in vivo. Intraperitoneal administration of gfKiss1–10 to sexually mature female goldfish could increase the serum LH levels. However, this peptide does not significantly influence LH release from goldfish pituitary cells in primary culture, indicating that the peptide does not exert its actions at the pituitary level. On the other hand, gfKiss2–10 appears to be a much less potent peptide as it exhibits no significant in vivo bioactivity and is also inactive on the primary pituitary cells.
Shedding light on the intricate puzzle of ghrelin's effects on appetite regulation
Authors: Kola Blerina , Korbonits Márta
Published: March 2009

Ghrelin, a hormone primarily produced by the stomach, has a wide range of metabolic and non-metabolic effects. It also stimulates food intake through activation of various hypothalamic and brain stem neurons. A series of recent studies have explored the intracellular mechanisms of the appetite-inducing effect of ghrelin in the hypothalamus, shedding light on the intricate mechanisms of appetite regulation. AMP-activated protein kinase (AMPK) is a key metabolic enzyme involved in appetite regulation. Calmodulin kinase kinase 2 (CaMKK2) has been identified as an upstream kinase of AMPK and a key mediator in the effect of ghrelin on AMPK activity. The fatty acid pathway, hypothalamic mitochondrial respiration, and uncoupling protein 2 have been outlined as downstream targets of AMPK and mediators of ghrelin's appetite stimulating effect. This short overview summarises the present data in this field.
Methane from biomass: process-integration aspects
Authors: Heyne S. , Harvey S.
Published: March 2009

The production of synthetic natural gas (SNG) via biomass gasification constitutes a promising option for biofuel manufacture due to its high conversion efficiency and diversity of end-use opportunities in different sectors. This paper presents a critical review of possible feedstock conversion paths from biomass to SNG via gasification. Similarities with research and development issues for coal gasification projects for SNG production are identified and the state of the art for the bottleneck stages of the conversion is discussed. The need for tools to improve process efficiency is clearly shown; the pinch methodology is a powerful tool for process integration and is of particular interest in this regard. Biofuel production processes often deliver multiple products and services such as heat, electricity and other by-products and are often referred to as polygeneration or biorefinery concepts. To take into account the multiple possible products and services resulting from SNG production, it is necessary to carefully define appropriate process performance indicators. For a sound assessment of the future potential of biomass-based SNG production, an evaluation of the most promising process alternatives against a background of possible future energy market scenarios is necessary.
The Challenge of Producing and Stimulating a Deep Sandstone-Carbonate Reservoir with Combined Organic and Inorganic Formation Damage
Authors: Mora José A. , Kondo Felix , Pinto Sandra González
Published: March 2009

Gigante-1A (G-1A) is a well that is located in Upper Magdalena Valley in Colombia, South America. It has been producing for almost 10 years today. There are several wells in this area that have been producing from sandstone and carbonate/dolomite reservoirs at different depths for more than 30 years and are still drawing interest from producers. There is a high interest in new well construction based on experiences from G-1A related to drilling, completion, production stages, reservoir analysis with stimulation techniques, and response-related identification of formation damage. A second well at the same depth is currently in progress.

The specific condition of water, oil, and gas flowing commingled to surface from the same zone, covering sandstone and carbonate formations with significant petro-physical differences and reservoir fluids has allowed for the establishment of best practices and identified areas of research to get improved responses.

A continuous learning curve focused on improving operational procedures and placement techniques has been built according to the mechanical status of the well before each intervention. Periodical interventions focused on organic deposition, emulsion blockage damages, and scaling related problems have helped to establish operational and treatment design procedures which contribute to effective stimulation results.

Continuous improvements related to chemical treatment designs, based on adjustments of formulations, radius of penetration, and placement techniques, have helped to ensure effectiveness. Chemical treatments have focused on organic, nature-related problems since the beginning. In particular, asphaltenes flocculation, have generated pore throat blockage because of asphaltenes deposition and emulsion blockage. Water cut increase over time has brought inorganic scaling problems. Corresponding solutions have been combined with organic stimulation treatments for removal and damage inhibition overtime. There is also a clear learning curve over the last seven years on well lifting in optimizing well production in conjunction with chemical treatments to maximize oil production.
Oil Shale ICP - Colorado Field Pilots
Authors: Fowler Thomas D. , Vinegar Harold J.
Published: March 2009

The massive size of the oil shale resource in the Western USA, particularly in the Green River Basin, has attracted numerous commercialization attempts from industry over the last 100 years. Although great sums of money have been invested and many professional careers have been devoted to the challenge, efforts thus far have not resulted in a commercial oil shale industry.

For more than 40 years, Shell has been active in the Green River oil shale seeking a process that could develop the 800 billion bbls of oil resource (RAND Corporation). Since 1980 Shell has focused on the In-situ Conversion Process (ICP) in which oil shale is heated by thermal conduction from a closely spaced array of electric resistance heaters. At approximately 650oF, the kerogen present in the oil shale is converted to oil, gas and water that can be produced by conventional means. Although the process is subject to mining statutes and regulations in the State of Colorado, no traditional mining is required.

This paper provides a brief history of attempts to commercialize oil shale in the United States and an overview of Shell's ICP technology, including its 1940s Swedish oil shale roots. It focuses on Shell's seven field pilots conducted in Colorado that address ICP recovery, heater testing, and freeze wall construction and performance.
Hydraulic Stimulation Techniques Applied to Injection Wells at the Salak Geothermal Field, Indonesia
Authors: Yoshioka Keita , Pasikki Riza , Suryata Indra , Riedel Kenneth L.
Published: March 2009

The Salak field is the largest developed geothermal resource in Indonesia. Steam production levels have been maintained at or above the rated power plant capacity for 15 years through periodic infill drilling and injection realignment. The reservoir management strategy for Salak involves injecting separated brine into deep wells on the margins of the reservoir where permeability is known to be low. A technique that has been used to enhance permeability in new injection wells combines hydraulic and thermal fracturing. This involves complex rock/fluid interactions and heat transfer relationships that must be considered in order to design appropriate injection rates, pumping times, and injection temperatures.

This paper describes the techniques used to characterize candidate wells and interpret surveillance data collected during long-term cold water injection experiments. Analyzing continuous measurements of well injectivity along with pressure transient data taken periodically shows the evolution of enhanced permeability during stimulation. A high degree of success has been achieved using these techniques at Salak, with significant improvements in well injection capacity. These results provide additional alternatives for managing injection to increase the ultimate heat recovery from the reservoir.
Shale Swelling Tests Using Optimized Water Content and Compaction Load
Authors: Ewy Russell T. , Morton E. Keith
Published: March 2009

Since preserved shale core is rarely available, swelling tests are usually performed by creating shale pellets using ground-up cuttings. Room-dry ground cuttings are mixed with water, and then compressed under load in a compaction cell. In this paper we study the effect of different water amounts and compaction loads for five different shales. We find that both the optimum amount of water to use, and the optimum compaction load, are functions of the shale porosity. Lower-porosity shales require less water and greater compaction load, compared to higher-porosity shales. Pore size distributions of pellets vs. intact samples, and pellet saturation calculations, reveal the reasons for this. We also find that the optimum amount of water further depends on the amount of smectite in the shale, because smectite-rich shales hold more water in the room-dry state. However, this held water is easily determined by comparing the weight of room-dry ground shale with the weight of oven-dry ground shale. Porosity is easily determined from shale in situ bulk density. We therefore present simple relationships for calculating the required water amount and compaction load. A ‘calculator’ is presented which is applicable to nearly all shales covering a large range of porosities and clay mineral contents. It requires only two inputs: the shale in situ bulk density (e.g. from a well log), and the oven-dried weight of the room-dry ground shale. This calculator allows one to easily determine the appropriate water amount and compaction load for creating an optimum shale pellet. These findings allow one to create optimum shale pellets for swelling tests, which come closest to reproducing the in situ shale and yet are also fully-saturated. With optimized pellets, drilling fluids and completion fluids can be confidently ranked in terms of ‘bestto-worst’ swelling for any particular shale, as shown by the example swelling results in this paper. Without using optimized pellets, test results can be affected by various testing artifacts, such as capillary swelling due to incomplete saturation.
Conceptual Models for Fast Tracking Decision Making in the Reservoir Management
Authors: Ogbe David O. , Iwere Fabian O. , Boukhelifa Linda , Gomez Ernie , Henshaw Ekeng
Published: March 2009

Conceptual models are used to solve specific problems in selected sectors of reservoirs; study production mechanisms; understand behavior of a particular process in a reservoir system, and assess impacts of changing input parameters during reservoir modeling. They are tools of choice for assessing risks, evaluating "worst-case" scenarios, validating analyst's intuition, and to support informed decision making. Our objective is to demonstrate via two case studies how conceptual numerical models were used to shorten the time required to make reservoir management decisions. The first case study involves making a decision, either to develop or sell an oil property. Target formation is sandstone saturated with heavy oil (12°API gravity) which is overlain by a gas cap. Conceptual numerical simulation models provided answers to two questions:

What is the impact of gas production from the gas cap on the underlying heavy oil zone? Can gas production from up-structure wells meet field deliverability requirements?

Second case study uses conceptual models to optimize well placement and support infill drilling. Infill well placement posed a challenge because thickness of target formation is not well known, and oil zone is bounded on top by a massive impermeable shale boundary, and by oil-water contact (OWC) located about 20-40 feet below.

Conceptual models answered the following questions:

What type of well to drill–vertical or horizontal? What is the impact of horizontal well's vertical placement (offset distance from OWC) on oil recovery and water breakthrough times? What is the optimum horizontal well lateral length and its impact on oil recovery?

This paper describes modeling methodology, major observations and conclusions. We discuss the benefits and lessons learned from the case studies and demonstrate that successful application of conceptual models requires identifying key well/reservoir performance drivers and assessing their impacts on the reservoir management decisions.
Water Problems and Control Techniques in Heavy Oils with Bottom Aquifers
Authors: Qin W. , Wojtanowicz A. K.
Published: March 2009

As conventional petroleum is approaching its maximum production and the world oil demand continues to grow, heavy oil becomes one of the obvious replacement resources. One of the most important problems in heavy oil recovery is dramatic loss of wells’ productivity at the onset of water inflow due to the two fluids’ mobility contrast. Not only the recovery at breakthrough time is very low, but also the water cut increase is extremely rapid.

The paper presents a worldwide survey of heavy oil reservoirs with water problems and their production methods including the in-situ water drainage with down-hole water sink (DWS) completion. It also investigates the mechanisms of productivity reduction and loss of recovery in wells producing heavy oil with bottom water drive.

In the study, the production system (nodal) analysis model simulates well's inflow performance relationship (IPR) with variable water cut. The results capture the difference between heavy and light oil in terms of mobility ratio effect, recovery dynamics prior to and after water breakthrough, and water cut control with production rate. The IPR performance of water drainage with DWS wells is also presented and discussed.
Seed Size Is Associated with Sucrose Synthase Activity in Developing Cotyledons of Chickpea
Authors: Turner Neil C. , Furbank Robert T. , Berger Jens D. , Gremigni Patrizia , Abbo Shahal , Leport Laurent
Published: March 2009

Seed size, a key quality determinant in the marketing of the cool‐season food legume chickpea (Cicer arietinum L.), can be reduced under terminal drought. Sucrose synthase and invertase, important enzymes in sugar metabolism, play an important role in seed filling. This study aimed to determine whether these enzymes in the developing cotyledons are associated with the final seed size of chickpea by following their level of activity during seed filling in large‐ and small‐seeded chickpea genotypes. The level of invertase in the cotyledons was unchanged during seed filling, but sucrose synthase reached a maximum about 500 to 600 growing degree days (GDD) after flowering when cell numbers were no longer increasing, but the cotyledons were increasing rapidly in dry weight. In a range of genotypes differing in seed size, the level of sucrose synthase activity in the developing cotyledons at 500 to 600 GDD was correlated with the final seed size at maturity when measured at a rainfed site in two different years. The level of activity of sucrose synthase at the same stage of development in F2, F3, and F7 populations of crosses between a large‐seeded cultivar and two small‐seeded genotypes was also correlated with final seed size. It is concluded that sucrose synthase, but not invertase, in developing cotyledons is the key enzyme influencing seed size in chickpea.
Nitrogen Source and Rate Effects on the Establishment of ‘TifSport’ and ‘Tifway’ Hybrid Bermudagrass
Authors: Guertal E. A. , Hicks C. A.
Published: March 2009

In the southeast United States, the most popular vegetatively propagated hybrid bermudagrass (Cynodon dactylon × C. transvaalensis Pers. L.) has long been the cultivar Tifway. In recent years, however, southern turf managers choosing cultivars for lawns, golf course fairways, or athletic fields have a newer option: ‘TifSport’ hybrid bermudagrass, also a vegetative selection. Although the use of TifSport is increasing, research that studies the establishment of TifSport is largely absent from the literature, as most past work has focused exclusively on Tifway. Thus, the objective of our research was to evaluate the establishment of Tifway and TifSport hybrid bermudagrasses when established from sprigs, examining the effect of N rate and N source of the rate of groundcover, shoot density, and stolon and rhizome development. The study was conducted in 2002 and 2004; in each year, new plots were fumigated and then sprigged with Tifway and TifSport. Nitrogen source treatments were ammonium nitrate (AN) (34‐0‐0) or calcium (Ca) nitrate (CaN) (16‐0‐0; 39% Ca), both applied at 2.4, 4.9, 7.3, or 9.8 g N m−2 wk−1. Treatments were a factorial combination of cultivar, N rate, and N source. Collected data included percentage groundcover as measured via line‐transect, shoot density, and dry weight of stolons and rhizomes. In both years, TifSport had higher percentage groundcover than Tifway at early measurement dates, with >95% groundcover for both cultivars at 7 and 5 weeks after sprigging for 2002 and 2004, respectively. Shoot density often increased as N rate increased, with shoot density maximized at N rates between 6.2 and 7.6 g N m−2 wk−1. In both years, dry weight of stolons and rhizomes decreased as N rate increased.
Cardiac Rhabdomyomas in Tuberous Sclerosis Complex Show Apoptosis Regulation and mTOR Pathway Abnormalities
Authors: Kotulska Katarzyna , Larysz-Brysz Magdalena , Grajkowska Wiesława , Jóźwiak Jarosław , Włodarski Paweł , Sahin Mustafa , Lewin-Kowalik Joanna , Domańska-Pakieła Dorota , Jóźwiak Sergiusz
Published: March 2009

Cardiac rhabdomyoma (CR) is the most common heart tumor in children and is usually associated with tuberous sclerosis complex (TSC). Tuberous sclerosis complex is a genetic disorder caused by a mutation in either of 2 genes (TSC1 or TSC2) and characterized by the formation of hamartomas in multiple organs. The 2 TSC proteins, hamartin and tuberin, antagonize the mammalian target of rapamycin (mTOR) signaling pathway, thus regulating cell growth and proliferation. Recently, some trials treating TSC with the mTOR inhibitor rapamycin have been published; however, the impact of such treatment on heart tumors is not known. The aim of the present paper was to study the molecular pathobiology of CRs. Six CR samples were studied. The expression of S6K1, pErk, Erk, Akt, pAkt, 4E-BP1, hamartin, tuberin, mTOR, bcl-2, Bax, and Ki-67 was examined using immunohistochemistry and Western blot methods. Increased expression of Bax, mTOR, pS6K, pErk, and 4E-BP1 was found in all CR samples. Hamartin and tuberin expression was decreased in tumors versus normal heart tissues. This is the first study showing mTOR pathway dysregulation and an increased expression of proapoptotic Bax protein in CRs associated with TSC.
Hepatoprotective effects of Calotropis gigantea extract against carbon tetrachloride induced liver injury in rats
Authors: Lodhi Gaurav , Singh Hemant , Pant Kamlesh , Hussain Zeashan
Published: March 2009

Hepatoprotective effects ofCalotropis giganteaextract against carbon tetrachloride induced liver injury in rats

Ethanolic extract (50 %) of stems ofCalotropis giganteaR. Br. (Asclepiadaceae) at doses of 250 and 500 mg kg-1were studied for hepatoprotective activity in male Wistar rats with liver damage induced using carbon tetrachloride, 2 mL kg-1twice a week. The protective effect ofC. giganteaextract was compared with the standard drug silymarin. Various biochemical parameters such as aspartate amino transferase (AST), alanine amino transferase (ALT), glutathione (GSH), lipid peroxide (LPO), superoxidedismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were evaluated. The results revealed that theC. giganteaextract significantly decreased AST, ALT (p< 0.001) and lipid peroxide (p< 0.01) levels. The antioxidant parameters GSH, GPx, SOD and catalase levels were increased considerably compared to their levels in groups not treated withC. giganteaextract.
Investigation of the structural requirement for inhibiting HIV integrase: QSAR study
Authors: Dessalew Nigus
Published: March 2009

Investigation of the structural requirement for inhibiting HIV integrase: QSAR study

HIV integrase has emerged as a promising target for discovery of agents against the acquired immunodeficiency syndrome (AIDS) pandemic. With the purpose of designing new chemotypes with enhanced potencies against the HIV integrase enzyme, the QSAR study carried out on 37 novel phthalimide derivatives is presented. The developed QSAR model was validated by standard statistical parameters and through a detailed structural study of how it reproduces and explains the quantitative differences seen in experimentally known pharmacological data. The model showed a good correlative and predictive ability having a cross-validated correlation coefficient (r2cv) of 0.709 and a conventional correlation coefficient (r2) of 0.949. The predictive correlation coefficient (r2pred) was found to be 0.512. The study revealed that the antiretroviral activity is predominantly explained by the substituent size, shape and polarity and provided insights into how modulation of the steric bulkiness and polarities of the substituents could be made to optimize the integrase-inhibitor interaction chemistry. A detailed investigation was made of the structural basis for the antiretroviral activity and the findings from the study could be usefully employed to design antagonists with a much more enhanced potency and selectivity.
Preclinical studies of [61Cu]ATSM as a PET radiopharmaceutical for fibrosarcoma imaging
Authors: Jalilian Amir , Rostampour Nima , Rowshanfarzad Pejman , Shafaii Kamaleddin , Kamali-Dehghan Mohsen , Akhlaghi Mehdi
Published: March 2009

Preclinical studies of [61Cu]ATSM as a PET radiopharmaceutical for fibrosarcoma imaging

[61Cu]diacetyl-bis(N4-methylthiosemicarbazone) ([61Cu] ATSM) was prepared using in house-made diacetyl-bis(N4-methylthiosemicarbazone) (ATSM) ligand and [61Cu]CuCl2 produced via the natZn(p, x)61Cu (180 μA proton irradiation, 22 MeV, 3.2 h) and purified by a ion chromatography method. [61Cu]ATSM radiochemical purity was >98 %, as shown by HPLC and RTLC methods. [61Cu]ATSM was administered into normal and tumor bearing rodents for up to 210 minutes, followed by biodistribution and co-incidence imaging studies. Significant tumor/non-tumor accumulation was observed either by animal sacrification or imaging. [61Cu]ATSM is a positron emission tomography (PET) radiotracer for tumor hypoxia imaging.
Development and biopharmaceutical evaluation of extended release formulation of tramadol hydrochloride based on osmotic technology
Authors: Kumar Pramod , Singh Sanjay , Mishra Brahmeshwar
Published: March 2009

Development and biopharmaceutical evaluation of extended release formulation of tramadol hydrochloride based on osmotic technology

Extended release formulation of tramadol hydrochloride (TRH) based on osmotic technology was developed and evaluated. Target release profile was selected and different variables were optimized to achieve it. Formulation variables such as the level of swellable polymer, plasticizer and the coat thickness of semipermeable membrane (SPM) were found to markedly affect drug release. TRH release was directly proportional to the levels of plasticizer but inversely proportional to the levels of swellable polymer and coat thickness of SPM. Drug release from developed formulations was independent of pH and agitation intensity but dependent on osmotic pressure of the release media.In vivostudy was also performed on six healthy human volunteers and various pharmacokinetic parameters (cmax,tmax,AUC0-24,MRT) and relative bioavailability were calculated. Thein vitroandin vivoresults were compared with the performance of two commercial TRH tablets. The developed formulation provided more prolonged and controlled TRH release compared to the marketed formulation.In vitro-in vivocorrelation (IVIVC) was analyzed according to the Wagner-Nelson method. The optimized formulation (batch IVB) exhibited good IVIV correlation (R= 0.9750). The manufacturing procedure was found to be reproducible and formulations were stable over 6 months of accelerated stability testing.
General Theory of Quasi-Commutative BCI-algebras
Authors: Sun Tao , Pan Weibo , Wu Chenglong , Liang Xiquan
Published: March 2009

General Theory of Quasi-Commutative BCI-algebras

It is known that commutative BCK-algebras form a variety, but BCK-algebras do not [4]. Therefore H. Yutani introduced the notion of quasicommutative BCK-algebras. In this article we first present the notion and general theory of quasi-commutative BCI-algebras. Then we discuss the reduction of the type of quasi-commutative BCK-algebras and some special classes of quasicommutative BCI-algebras.
Linear Map of Matrices
Authors: Pąk Karol
Published: March 2009

Linear Map of Matrices

The paper is concerned with a generalization of concepts introduced in [13], i.e. introduced are matrices of linear transformations over a finitedimensional vector space. Introduced are linear transformations over a finitedimensional vector space depending on a given matrix of the transformation. Finally, I prove that the rank of linear transformations over a finite-dimensional vector space is the same as the rank of the matrix of that transformation.
Basic Properties and Concept of Selected Subsequence of Zero Based Finite Sequences
Authors: Nakamura Yatsuka , Ito Hisashi
Published: March 2009

Basic Properties and Concept of Selected Subsequence of Zero Based Finite Sequences

Here, we develop the theory of zero based finite sequences, which are sometimes, more useful in applications than normal one based finite sequences. The fundamental function Sgm is introduced as well as in case of normal finite sequences and other notions are also introduced. However, many theorems are a modification of old theorems of normal finite sequences, they are basically important and are necessary for applications. A new concept of selected subsequence is introduced. This concept came from the individual Ergodic theorem (see [7]) and it is the preparation for its proof.
The Role of Interphase Boundaries in the Deformation Behaviour of Fine-Grained Sn-38wt.%Pb Eutectics
Authors: Muktepavela F. , Bakradze G. , Zabels R.
Published: March 2009

The Role of Interphase Boundaries in the Deformation Behaviour of Fine-Grained Sn-38wt.%Pb Eutectics

The mechanical properties of binary Sn-38wt.%Pb eutectic alloys in the deformed and annealed states were investigated at room temperature using tensile, micro- and nano-indentation tests. The softening and high plasticity of a deformed Sn-Pb eutectic are explained as a result of grain boundary sliding (GBS) and fast diffusion-driven processes developing along the Sn-Pb interphase boundaries (IBs). From the results of micro- and nano-hardness measurements it follows that the Sn and Pb phases in the annealed eutectic are strengthened, and the relaxation processes occur mainly at the IB. Such IBs in the annealed Sn-Pb eutectic act as barriers to the motion of a dislocation ensemble when the size of the plastic zone is comparable with the grain size, lowering the hardness values due to the development of GBS when more grains are involved in the process of deformation. The nanohardness and elastic modulus values obtained evidence that an IB in the Sn-Pb eutectic is to be considered as a separate phase with its own mechanical properties.