bluuebunny/crossref_metadata_2025_split huggingface dataset:
Generation of artificial channels by multimerization of β-strands from natural porin
Authors: Lolicato Marco , Reina Simona , Messina Angela , Guarino Francesca , Winterhalter Mathias , Benz Roland , De Pinto Vito 
Published: June 2011

AbstractGeneral diffusion porins are passive transmembrane channels. We have explored the possibility to create artificial nanopores starting from natural β-barrel structures. Structural elements of bacterial porins were used to build a series of artificial nanopores. The basic module was selected by multi-alignment of general diffusion porins. The sequence corresponded to a highly conserved motif containing two β-strands, which was obtained fromEscherichia coliOmpF. Dimeric to octameric repeats were obtained through cDNA recombinant technology. The hexameric repeat was used to test its properties. This protein was expressed, purified and reconstituted in the planar bilayer membranes. It was able to form channels in membranes with a conductance of 300 pS in 150 mmKCl and did not show any relevant voltage-dependence.
Novel neutrophil inhibitory factor homologue in the buccal gland secretion of Lampetra japonica
Authors: Xue Zhuang , Bai Jie , Sun Jing , Wu Yu , Yu Shui Yan , Guo Ren Yong , Liu Xin , Li Qing Wei 
Published: June 2011

AbstractTo identify the functional gene fragment, a neutrophil inhibitory factor (NIF) like protein was found in the buccal gland ofLampetra japonica, suggesting that this related lamprey protein represents a novel class of integrin receptor antagonists. The recombinantLampetra japonica-NIF like (rLj-NIF) was identified by SDS-PAGE and purified by using His·Bind affinity chromatography. Effect of rLj-NIF on neutrophil migration suggested that rLj-NIF can act as a neutrophil inhibitory factor. Besides that, oxidative burst activity of neutriphil was tested by flow cytometry using dihydrorhodamine (DHR123) as a fluorogenic substrate, and the data suggested that the mean fluorescence intensity significantly decreased compared with positive controls (p<0.01). All above results indicated that rLj-NIF could also prevent the binding of β2 integrins to the surface of PMN and its FITC-labeled monoclonal antibodies (p<0.05). These data suggest thatLampetra japonica-NIF like protein is secreted by the stage of the parasite at the site of attachment. rLj-NIF plays an essential role in physiological reaction of neutrophil by a novel class of β2 integrin receptor antagonists. The activity of immunosuppressant ofL.japonica-NIF could have potential medicinal value in anti-inflammation and therapy of autoimmune diseases.
Impact of aryl hydrocarbon receptor (AhR) knockdown on cell cycle progression in human HaCaT keratinocytes
Authors: Kalmes Michaela , Hennen Jenny , Clemens Judith , Blömeke Brunhilde 
Published: June 2011

Abstract
While activation of the aryl hydrocarbon receptor (AhR) by exogenous ligands is well investigated, its physiological function is less understood. By extending research in AhR biology, evidence appeared that the receptor generally plays an important role in cell physiology. In keratinocytes, little is known about endogenous functions of the AhR. In order to expand this knowledge, we analyzed the impact of AhR knockdown on cell cycle progression in HaCaT cells and showed that proliferation of siAhR HaCaT cells was significantly decreased. In line with that result, western blot analysis revealed that protein level of the cyclin dependent kinase inhibitor p27KIP1 was increased, whereas protein level of the cyclin dependent kinase (CDK) 2 was reduced. CDK4 and CDK6 protein levels remained unchanged, whereas protein level of the retinoblastoma protein (pRB) was reduced. By measuring ethoxyresorufin-O-deethylase (EROD) activity we showed that endogenous cytochrome P450 1 (CYP1), especially CYP1A1 is required for normal cell cycle in HaCaT cells, as well. To the best of our knowledge, we provide evidence for the first time in human skin cells, that in the absence of exogenous ligands, the AhR promotes cell cycle progression in HaCaT cells and one can speculate that this is the physiological function of this receptor in keratinocytes.
Laboratory assessment of iron status in pregnancy
Authors: Walsh Thomas , O'Broin Sean D. , Cooley Sharon , Donnelly Jennifer , Kennedy John , Harrison Robert F. , McMahon Corinna , Geary Michael 
Published: June 2011

Abstract

Background: Efforts to improve maternal nutrition during pregnancy prompted an observational study of the occurrence of maternal iron deficiency and its laboratory diagnosis in almost 500 pregnancies.

Methods: In this longitudinal study, the biochemical and haematological iron indices of women (n=492) attending a prenatal clinic in a Dublin maternity hospital were assessed at first booking (mean 15.9 weeks), and after 24 weeks, and 36 weeks of gestation. Full blood counts were measured. Serum ferritin (SF), zinc protoporphyrin (ZPP), and transferrin receptor (sTfR) concentrations were assayed and transferrin receptor index (sTfR-Index) was calculated. The occurrence of low values and their diagnostic values were considered.

Results: A high occurrence iron deficiency (ID) at first booking (SF<12 μg/L) had increased over six-fold by 24 weeks, and all biochemical iron indices reflected progressive iron depletion right up to term. The WHO recommended anaemia “cut-off” (Hb<110 g/L) was insensitive to biochemical iron deficiency at booking, missing over 90% of the low SF values (SF<12 μg/L) which were mostly associated with much higher Hb levels.

Conclusions: This study stresses the importance of including a biochemical index of iron status in prenatal screening and supports SF as the best indicator of biochemical ID overall. sTfR was insensitive to iron deficiency in early pregnancy, whereas the sTfR-Index, as a ratio, has the potential to distinguish between ID and physiological anaemia, and may offer stability in the assessment of iron stores from early pregnancy to full term. A policy of early screening of both Hb and SF concentrations is recommended as the minimum requirement for surveillance of maternal iron status in pregnancy.
Calcium pyrophosphate and monosodium urate crystals in synovial fluid as a cause of pseudoeosinophilia
Authors: Robier Christoph , Neubauer Manfred , Quehenberger Franz , Stettin Mariana , Rainer Franz 
Published: June 2011

Abstract

Background: Synovial fluid (SF) leukocytes can be counted microscopically in a Neubauer chamber or by automated procedures using haematology analysers. Knowledge of laboratory artefacts is crucial for the correct interpretation of results obtained using automated methods. SF pseudoeosinophilia has recently been described as a new artefact in patients with crystal-related arthropathies. We investigated whether pseudoeosinophilia of SF is restricted to crystal-related disorders, or if it may also occur in other arthropathies.

Methods: We compared the percentages of eosinophils in 120 crystal containing SF samples with 185 crystal-free specimens using the Wilcoxon test. Crystal positive samples, determined by polarised microscopy, contained at least two monosodium urate or calcium pyrophosphate crystals per 10 high power fields (630× magnification). True SF eosinophilia was ruled out by microscopic examination of stained slides.

Results: Crystal positive samples had significantly higher percentages of eosinophils than the controls (p<0.0001). No significant differences between the two crystal types were found (p=0.693). Thus, pseudoeosinophilia was significantly correlated with the presence of crystals, and none of the distinct crystal types was more likely to be associated with pseudoeosinophilia.

Conclusions: In this study, SF pseudoeosinophilia was confirmed as a crystal-related laboratory artefact which has to be considered in the interpretation of automated SF leukocyte differential counts.
Global uniqueness in determining electric potentials for a system of strongly coupled Schrödinger equations with magnetic potential terms
Authors: Liu Shitao , Triggiani Roberto 
Published: June 2011

Abstract
We consider the inverse problem of determining simultaneously two unknown electric potential coefficients for a system of two general strongly coupled Schrödinger equations, with magnetic potential terms, and with Neumann boundary conditions, from single Dirichlet measurements on a portion Γ1 of the boundary. Under suitable geometrical assumptions on the complementary unobserved portion Γ0 of the boundary, we show that one can uniquely determine the two unknown potential coefficients in one shot, from respective Dirichlet boundary measurements on Γ1 over an arbitrarily short time interval. The proof is based on a recent Carleman estimate in [Lasiecka, Triggiani and Zhang, J. Inv. Ill-Posed Problems 12: 43–123, 2004] for single Schrödinger equations. It also takes advantage of a convenient route “post-Carleman estimates” suggested by [Isakov, Inverse Problems for Partial Differential Equations, Springer, 2006, Theorem 8.2.2, p. 231].
Estimation of accuracy of finite-dimensional methods of regularization
Authors: Tanana Vitaly P. , Yaparova Natalya M. 
Published: June 2011

Abstract
We consider the estimation of the accuracy of finite dimensional approximations of regularized solutions for inverse problems in a separable Hilbert space. A connection of the regularization parameter with the estimates of error for these approximations and with the estimates of initial date is obtained. For the establishment method the estimation of error of the finite-dimensional approximation is obtained. This estimate is exact with respect to the order.
Overweight, Obesity, Diabetes, and Risk of Breast Cancer: Interlocking Pieces of the Puzzle
Authors: La Vecchia Carlo , Giordano Sharon H. , Hortobagyi Gabriel N. , Chabner Bruce 
Published: June 2011

Abstract
We considered epidemiological data on overweight, diabetes, insulin, and breast cancer. Overweight is inversely related to premenopausal breast cancer, but there is definite evidence that, as compared with normal weight women, the relative risk (RR) for postmenopausal breast cancer is around 1.5 for overweight women and &gt;2 for obese women, and that the association is stronger in elderly women. Overweight and obesity are strongly related to diabetes. Diabetes is associated with postmenopausal breast cancer, too, with summary RRs from meta-analyses of 1.15–1.20, but not with premenopausal breast cancer (RR, 0.9). There is no consistent evidence that fasting insulin is related to breast cancer risk. Thus, although overweight and obesity are strongly related to postmenopausal breast cancer, diabetes is only moderately related to it. Given the extent of the association, and the likely residual confounding by overweight, inference on causality for the diabetes–breast cancer relation remains open to discussion.
Comparison of Core/Log and Well Test Permeabilities - A Closer Look "Sawan Tight Sands"
Authors: Ahmed Amir Riaz , Ahmad Mansoor , Rehman Attique ur 
Published: May 2011

Abstract
Permeability values are available through many sources e.g. cores, logs and well testing. It is a usual practice to condition log data with core, but integration of well test data is usually left for later stages when building 3D reservoir models. It is often observed that core/log results do not agree with well test results. This becomes usually very prominent in tight sand wells. The usual suspect is formation damage during drilling and completion operations, but the real cause may only be revealed by an in-depth analysis of the available data.
Core/log results usually give absolute permeabilities, whereas well tests provide effective permeabilities for the fluid under consideration. The role of cut-offs is very important when core/log permeabilities are calculated e.g. porosity, water saturation, clay volume etc. To compare with Well test permeabilities, the effect of over burden pressure, the gas slippage effect and relative permeability effect should be considered.
The noticeable difference in core/log permeabilities and well test permeabilities is analyzed in this paper and compared with other industry reported cases.
Gas Pricing Under Petroleum Policy 2001: Explaining the Unexplainable
Authors: Tanveer Atif 
Published: May 2011

Abstract
Petroleum (Exploration & Production) Policy 2001 was announced in May 2001 by the Ministry of Petroleum & Natural Resources (MPNR), Government of Pakistan with an objective to create an investor friendly climate and attract exploration investment in the country. Besides offering certain fiscal incentives the Policy was specifically formulated to give a revised gas pricing mechanism to the E&P sector to achieve that objective. Since gas pricing mechanism given in the earlier Petroleum Policy announced in 1997 had no oil price floor and ceiling limits; hence the gas price under the said Policy was more susceptible to the price shocks, the MPNR, therefore, wanted to rationalize the gas pricing framework of all Petroleum Concession Agreements (PCAs) signed under 1997 Policy with the improved pricing mechanism of the upcoming 2001 Policy.
However, when keenly awaited 2001 policy was announced, much to MPNR’s frustration, its gas pricing criteria was termed as vague by most of the E&P companies. That so called uncertainty later turned into an all-time-big controversy between the MPNR and the petroleum companies when the latter approached the Ministry for the determination of gas prices of their discoveries made under the new 2001 Policy.
The underlying paper thoroughly reviews the gas pricing mechanism given in 2001 petroleum policy and its various interpretations given by the Government and the E&P sector. The paper also highlights the limitations of each of the interpretations using examples based on actual data. At the end paper explains the gas pricing mechanism as given in 2001 policy and concludes that pricing mechanism is not incorrect or wrongly worded but it is primarily the wrong interpretation of the gas pricing formula and the misunderstanding which has led to the controversy between the Government and the E&P companies.
Multi Services Unit - Cost Effective Solution for Wireline & Slickline Services (Pakistan Case Histories)
Authors: Qureshi I. , Ashraf M. , Khattak K. , Jamil A. H. , Mahmood S. , Sair M. T. , Qureshi S. 
Published: May 2011

Abstract
The continuous need in oil & gas industry for technologies and techniques which not only improve the operational quality and efficiency but can also save time and money has resulted in the development of Multi Services Unit (MSU) which provides both wireline and slickline services in a single unit.
Typically, when both wireline and slickline services are required for well intervention operation, separate wireline and slickline unit and personnel are used. Separate arrangement for logistic, personnel accommodations and security are required on top of the daily cost incurred for having both units on the wellsite. Each slickline and wireline unit have applications of its own and even with the latest advances in tools technology, there is limited wireline application that slickline unit can performed and vice-versa. The introduction of MSU will help to reduce the well intervention costs as well as rig time. In addition, the need to use expensive memory logging tools on slickline unit can be avoided as the conventional logging tools can still be used on MSU.
This paper discusses the successful introduction of MSU in Pakistan. MSU was utilized in more than 75 operations in Pakistan with various E&P operators in its first six month. MSU has so far provided both slickline and wireline solutions ranging from slickline completions jobs, memory gauges logging, perforation via slickline/wireline, wireline correlations, wireline bridge plug settings, wireline pipe recovery and production packer setting. All these operations were executed by a single unit and crew. The paper evaluates the cost effectiveness of MSU as opposed to typical use of separate slickline and wireline units. It evaluates additional advantages profited by the E&P operators through the use of MSU such as reduced logistic, accommodation, security requirements, reduced equipment footprints and reduced rig time. The paper also describes conversion process from slickline unit into MSU, the initial complications, continuous improvements and lessons learned made during MSU introduction.
In conclusion, the Multi Services Unit is proven to be an economically attractive solution which helped to reduce well intervention cost without sacrificing the operation quality and safety.
Hydraulic Fracturing Of Tight Gas Reservoir Of Pab Sandstone At POGC Rehman-1
Authors: Nizamuddin M. , Aizad Tanweer , Andress G. R. , Korosa Marko 
Published: May 2011

Abstract
POGC Rehman-1 discovered gas from the Pab sandstone in mid-2009. The well had low productivity primarily due to low reservoir permeability. In December 2009, the well’s Upper and Lower Pab zones were fractured, resulting in a four-fold increase in production. Post-frac testing of the zones discovered very little proppant flowback.
This paper outlines the history of this successful hydraulic fracturing treatment in the Kirthar region. The document also discusses the detailed job design, fracture modeling, pre-frac production model calibration, and sensitivities to treatment size. A series of fracture designs was developed to evaluate the uncertainty in fracture geometry predictions. The successful stimulation of a low-permeability gas reservoir dictated placing a long conductive fracture.
An important aspect of fracture design is fluid selection. The fluid must maintain excellent proppant transport characteristics throughout the pumping sequence, yet break rapidly and cleanly once the treatment is completed. Another important aspect of fracture design: proppant selection. The proppant is basically the life of the fracture and should maintain adequate conductivity throughout the designed exploitation life of the fracture and completion.
The fracturing program and the main treatment’s actual execution are presented in the paper. Operational issues are also discussed. One-hundred mesh sand was used to minimize the risks associated with pressure dependent leakoff (PDL) into natural hairline fractures seen on the FMI log. Post-fracture well-testing data was recorded and analyzed. The results were used to quantify the fracture effectiveness.
A Unique Methodology To Estimate Fracture Permeability in Naturally Fractured Reservoirs (NFR)
Authors: Ulhaq Shahzad , Salehi Fereydoun 
Published: May 2011

Abstract
Fracture Permeability is one of the key parameter in determining the producibility of a Naturally Fractured Reservoir (NFR). Fluid flow in naturally fractured reservoirs is controlled largely by the distribution, orientation, and interconnectivity of the fracture system. The characterization of Naturally Fractured Reservoirs (NFR) represents additional challenges to that of conventional reservoirs because it is not only required the description of two separate means (matrix and fracture) but also it is necessary to undertand their interaction. Among the list of potential parameters that can contribute to understand the complexity of NFR is the fracture permeability. It is very important to estimate the fracture permeability correctly for the successful development of NFR, because the fractures have considerably higher permeability and govern the fluid flow in the reservoir1. These reservoirs commonly have low matrix permeabilites (to md), and a well-developed natural fracture system must be present to provide sufficient deliverability for economic production. A detailed fracture analysis is crucial to estimate fracture permeability in NFR.
In this paper, we present an integrated unique methology for estimating fracture permeability by utilizing logs, borehole images and production data. The results of this methology were encouraging and helped to estimate fracture permeability in the naturally fractured reservois (NFR).
First Hydraulic Fracturing Treatments Improve HPHT Well Offshore India
Authors: Stolyarov Sergey , Dean Greg 
Published: June 2011

Abstract
A stimulation vessel has pumped the first hydraulic fracture treatments in high-pressure, high-temperature (HPHT) tight gas well in the Krishna-Godavari basin offshore India, spurring a four-fold increase in productivity.
The Krishna-Godavari basin holds one of the largest gas reservoirs in India, making it a highly prospective region for exploration. Initial analysis indicated that the tight gas formation would have to be hydraulically fractured to optimize productivity, but its high temperatures and pressures, and its location create challenges for both logistics and technology.
This paper will describe the process of designing and executing several hydraulic fracture treatments in an area with no prior stimulation history, and the results of the work. It will include laboratory evaluations of rock mechanics, mineralogy and permeability, as well as frac fluid stability and proppant pack conductivity at expected downhole temperatures of 400°F. It will also show how minifrac analyses were performed prior to the main frac treatments to verify assumptions about rock and fluid properties and optimize each treatment. Successful stimulation treatments were incorporated into the reservoir model, allowing a more detailed and realistic productivity forecast. Results demonstrated the economic value of including hydraulic fracturing in the full field development plan.
Maximising Natural Gas Reserves and Profitability Through Best Practice Studies Methodologies: A case Example by SPDC Gas Cluster Team
Authors: Udofia Abasiubong , Meijssen Thomas , Ebong Ufot , Foley Mary , Sturman Liz 
Published: May 2011

Abstract
Natural gas is becoming an increasingly important source of the world's energy, with the growth in demand for it as a fuel being encouraged by global concern for the environment, gas lower price and relative abundant to other energy sources. This hyper growth in demand comes with its attendant challenges.
In Nigeria, the Liquefied Natural Gas (NLNG) plant in Bonny is undergoing rapid expansion to meet this growth in demand. For Shell Petroleum Development Company Nigeria (SPDC), the challenge to prove up reserves to meet up with the attendant demand, through subsurface developmental studies is one that is handle through the integration of innovative techniques and processes for integrated field studies. Nodal (cluster) development approach, Opportunity Realisation (ORP) and Hydrocarbon Development Planning (HDP) Processes, 3D-all- the –way (3DATW) modelling process and the application of reservoir simulators interface with a surface facility network using the Hydrocarbon Field Planning Tool (HFPT), are proven innovations.
This paper highlights how these innovative integration and rigorous uncertainty management techniques have been used to prove up reserves and produced robust development plans for the several Nodal gas development projects in SPDC, Nigeria, and poised to meet the Nigerian Liquefied Natural Gas (NLNG) production trains 1-6 (T1-6) gas supply contractual obligations.
Contemplating Criminal Liability for the Consequences of Unlawful Data Disclosure
Authors: Finch Emily 
Published: June 2011

AbstractThis article considers whether the current approach of the criminal law to the unauthorised disclosure of personal data is adequate to deal with situations in which this disclosure has facilitated the commission of some other criminal offence. It argues that the focus of the criminal law should be on the consequences of disclosure and that there are strong policy arguments in favour of imposing liability on the person making disclosure for the offence that has been committed as a consequence of this conduct. In doing so, the article considers whether this could and should lead to the imposition of liability for constructive manslaughter if the disclosure of personal data leads to the death of the person to whom the data relates. The article concludes by suggesting that the most appropriate response is to strengthen the existing law with creation of a new offence that would focus on the consequences of disclosure.