bluuebunny/crossref_metadata_2025_split huggingface dataset:
From structure topology to chemical composition. XI. Titanium silicates: crystal structures of innelite-1Tand innelite-2Mfrom the Inagli massif, Yakutia, Russia, and the crystal chemistry of innelite
Authors: Sokolova E. , Cámara F. , Hawthorne F. C. 
Published: June 2012

AbstractThe crystal structures of two polytypes of innelite, ideally Ba4Ti2Na2M2+Ti(Si2O7)2[(SO4) (PO4)]O2[O(OH)] where M2+= Mn, Fe2+, Mg, Ca: innelite-1T,a5.4234(9),b7.131(1), c 14.785(3) Å, α 98.442(4), β 94.579(3), γ 90.009(4)°,V563.7(3) Å3, space groupP1̄,Dcalc= 4.028 g/cm3, Z = 1; and innelite-2M,a5.4206(8),b7.125(1),c29.314(4) Å, 0 94.698(3)°,V1128.3(2) Å3, space groupP2/c,Dcalc.=4.024 g/cm3,Z =2, from the Inagli massif, Yakutia, Russia, have been refined toRvalues of 8.99 and 7.60%, respectively. Electron-microprobe analysis gave the empirical formula for innelite as (Ba3.94Sr0.06)Σ4.00(Na2.16Mn0.382+Fe2+0.17Mg0.15Ca0.10☐0.04)Σ3(Ti2.97Nb0.02Al0.02)Σ3.01Si4.01(S1.02P0.81☐0.17)Σ2H1.84O25.79F0.21which is equivalent to (Ba3.94Sr0.06)Σ4.00(Ti1.97Nb0.02Al0.02)Σ2.01[(OH0.99F0.21)Σ1.20O0.80], calculated on the basis of 26 (O + F) anions, with H2O calculated from structure refinement. The crystal structure of innelite is a combination of a TS (titanium silicate) block and an I (intermediate) block. The TS block consists of HOH sheets (H-heteropolyhedral, O-octahedral) and exhibits linkage and stereochemistry typical for Ti-disilicate minerals of Group III (Ti = 3 a.p.f.u.): two H sheets connect to the O sheet such that two (Si2O7) groups link to thetransedges of a Ti octahedron of the O sheet. The I block containsTsites, statistically occupied by S and P, and Ba atoms. In the structures of innelite-1Tand innelite-2M, TS blocks are related by an inversion centre and a cyglide plane, respectively. HRTEM images show a coherent intergrowth of the two polytypes, together with an as-yet unidentified ∼10 Å phase.
Distinct repeat motifs at the C-terminal region of CagA of Helicobacter pylori strains isolated from diseased patients and asymptomatic individuals in West Bengal, India
Authors: Chattopadhyay Santanu , Patra Rajashree , Chatterjee Raghunath , De Ronita , Alam Jawed , Ramamurthy T , Chowdhury Abhijit , Nair G Balakrish , Berg Douglas E , Mukhopadhyay Asish K 
Published: June 2012

Abstract

Background
Infection with Helicobacter pylori strains that express CagA is associated with gastritis, peptic ulcer disease, and gastric adenocarcinoma. The biological function of CagA depends on tyrosine phosphorylation by a cellular kinase. The phosphate acceptor tyrosine moiety is present within the EPIYA motif at the C-terminal region of the protein. This region is highly polymorphic due to variations in the number of EPIYA motifs and the polymorphism found in spacer regions among EPIYA motifs. The aim of this study was to analyze the polymorphism at the C-terminal end of CagA and to evaluate its association with the clinical status of the host in West Bengal, India.

Results
Seventy-seven H. pylori strains isolated from patients with various clinical statuses were used to characterize the C-ternimal polymorphic region of CagA. Our analysis showed that there is no correlation between the previously described CagA types and various disease outcomes in Indian context. Further analyses of different CagA structures revealed that the repeat units in the spacer sequences within the EPIYA motifs are actually more discrete than the previously proposed models of CagA variants.

Conclusion
Our analyses suggest that EPIYA motifs as well as the spacer sequence units are present as distinct insertions and deletions, which possibly have arisen from extensive recombination events. Moreover, we have identified several new CagA types, which could not be typed by the existing systems and therefore, we have proposed a new typing system. We hypothesize that a cagA gene encoding higher number EPIYA motifs may perhaps have arisen from cagA genes that encode lesser EPIYA motifs by acquisition of DNA segments through recombination events.
Family perspectives in lynch syndrome becoming a family at risk, patterns of communication and influence on relations
Authors: Bartuma Katarina , Nilbert Mef , Carlsson Christina 
Published: June 2012

Abstract

Background
A growing number of individuals are diagnosed with hereditary cancer. Though increased levels of anxiety and depression have been demonstrated around the time of genetic counselling, most individuals handle life at increased risk well. Data have, however, been collected on individual basis, which led us to focus on family perspectives of hereditary cancer.

Methods
Lynch syndrome represents a major type of hereditary colorectal and gynaecological cancer. We preformed open-ended interviews with 27 informants from 9 Lynch syndrome families. Inductive content analysis revealed three major themes: transition to a risk family, patterns of communication and influence on family relations and individual roles.

Results
Family members described how learning about Lynch syndrome shifted focus from daily issues to concerns about cancer. Changes in communication related to difficulties in talking to children about heredity and informing new family members and distant relatives about an increased risk of cancer. Influence on relations was exemplified by family members taking on different roles, e.g. females often being responsible for coordinating information about heredity and providing support. Families in which members had experienced cancer at young age typically informed children soon after learning about heredity and at young age, whereas families with experience of cancer at higher age postponed information and thereby also genetic counselling.

Conclusions
Three major family perspectives are described in Lynch syndrome families; becoming a risk family, patterns of communication and influence on family relations. Since these issues are central, our findings suggests that such family perspectives should be considered during genetic counselling in order to contribute to information spread, help family members cope with the increased risk, and motivate family members at risk to undergo surveillance.
An Approach to Oil Production Forecasting in a WAG Process Using Natural CO2
Authors: Ligero Eliana L. , Mello Samuel F. , Muñoz Mazo Eduin O. , Schiozer Denis J. 
Published: June 2012

Abstract
The water-alternating-gas process (WAG) was originally proposed to improve sweep efficiency during gas injection and it combines the advantages of gas and water flooding, better microscopic displacement efficiency and improved macroscopic sweep, respectively. Carbon dioxide is an attractive gas to be used in the Enhanced Oil Recovery (EOR) process, mainly, when the oil in place contains some dissolved CO2 which is produced in the gas phase. The WAG-CO2 can be an attractive recovery method in reservoirs with oil containing CO2. Also, it is a manner to store CO2, representing a viable solution to the greenhouse gas problem. In WAG process simulation, it is necessary to shut-in and shut-off the injector wells alternately in order to change the injection fluid. This procedure results in an elevated simulation time compared to the EOR process with injection of a unique fluid. A numerical approach is investigated to physically represent the WAG process with reduced computational time. In this approach, denominated as Pseudo WAG process, water and CO2 are simultaneously injected into the simulation model, maintaining the same amount of injected fluid. The possibility of the Pseudo WAG process to adequately represent the WAG-CO2 is analyzed using a compositional simulator. To execute the simulations, it is necessary to have equations of state (EOS) that properly represent the oil phase behavior. EOS tuning is based on PVT experimental data of oil available in literature. The EOS is validated before being used in a simulation model. Results indicate that WAGCO2 is an effective method to recover oil containing CO2. The Pseudo WAG process is capable of adequately representing the WAG-CO2 process in terms of production parameters, such as cumulative oil and water productions. The numerical approach of the Pseudo WAG process significantly reduces the simulation time compared to the WAG process. This approach can be useful to simulate WAG-CO2 processes in heterogeneous reservoirs in order to reduce the CO2 emissions into the atmosphere.
Evaluation of a Smart Well System at the Saramacca Oil Fields-A Case Study
Authors: Griffith Cliff R. , Simon Leslie , Chin A Lien Henk 
Published: June 2012

Abstract
Well performance is monitored on a monthly base with the volume flow test and Flowing Bottom Hole Pressure (FBHP) measurements. In addition, down hole pressure data is also collected for build up tests and other reservoir studies. A very practical solution for this is to have a fully automated smart well system, which allows instant data access and also the ability to troubleshoot online real-time data.
Combining Thorough Coring Calibration and Latest Wireline Logging Technologies to Unravel LRP/LCP Challenges in Peru
Authors: Vasquez M. , Pinto C. , Mengual J-F. , Repsol F. Rodriguez , Vasquez J. 
Published: June 2012

Abstract
Since the early days of the technique of well logging and the original water saturation equation developed by Archie, low-resistivity pay was, practically speaking, a contradiction in terms. Through the years, however, this critical topic and its practical implication for the exploration and development of oil & gas reservoirs has become recognized as a worldwide phenomenon of particular and challenging interest.
For this specific study, we will focus in the continental deposits, mainly composed of eolian facies, of the pre-Cretaceous Nia formation that we can further sub-divide into two main prospective dry gas units. The idiosyncrasy of these two siliciclastic bodies is that they are exhibiting a lack of resistivity contrast between sands and adjacent shales and also with the water filled bottom section of the reservoir, resulting in complex formation evaluation process and problematical reserve calculation because the standard and practical "a, m & n" values are not anymore appropriate.
Despite a uniform mineralogy and clay content, the overall small grain size and relatively elevated amount of feldspars contribute actively to the presence of irreducible water which is not directly related to clay content but to micro-porosity, that creates a "low contrast resistivity" pay (LCP) effect. Furthermore, when micro-pores are present, they exert a gradually increasing influence as Sw decreases. Their effect is to decrease the saturation exponent "n" and this reduction is related to the degree of surface conduction constraints on current flow.
Therefore, we will present in this work a petrophysical approach that was adopted and validated in order to overcome these difficulties by combining a systematic and exhaustive laboratory core calibration along with proficient logging techniques (i.e. mineralogical & NMR). In these relatively freshwater shaly sands logged conductivity is imperfectly modeled and unsuitable to derive an exact water saturation necessary for a precise OGIP calculation. Uncertainties will arise from a combination of various phenomenon including lack of resistivity contrast between pay and non-pay, dissimilarity in shape and size of the sand grains, variable irreducible water content and lack of knowledge of the effective concentration of clay exchange cations. Nevertheless, we will illustrate and evidence that it is still possible to resolve this LCP challenge with the integration of discrete core data, reliable continuous specialized electrical logs and non-linear saturation equation.
Comparison of WAG and Water Over Injection for Carbon Storage and Oil Recovery in a Heavy Oil Field
Authors: Sobers L. E. 
Published: June 2012

Abstract
Compositional reservoir simulation studies show that CO2 enhanced oil recovery (CO2EOR) combined with carbon storage using water over gas injection improves production performance and carbon storage compared to WAG injection. The fluid description is based on matching the PVT-derived viscosity, total and relative volume of a heavy oil sample (density 893 kg/m3 [17 degrees API]). The reservoir description is based on an unconsolidated deltaic, sandstone deposit in the Gulf of Paria, offshore Trinidad. Water over gas injection is an injection strategy proposed by Stone and Jenkins to increase gas sweep efficiency. In this injection design water is injected in the upper portion of the reservoir and gas is injected in the bottom portion of the reservoir using either vertical or horizontal injectors. Increasing the sweep efficiency improves both oil recovery and carbon storage. The counter current flow of injected fluids uses gravity effects to reduce gas override and water underride typical of WAG injection strategies and continuous single fluid injection. The results show that the water over gas injection design results in a larger mixing zone that extends further into the reservoir. Although oil recovery was essentially the same, with water over gas injection, there was greater than 50% increase in carbon storage, 20% reduction in water cut and 85% reduction in producing GOR compared to WAG.
Continuous Improvement and Oversight for Deepwater Cement Programs
Authors: Bogaerts M. , DeBruijn G. G. , Khalilova P. , Moretti F. , Voon E. 
Published: June 2012

Abstract
The deepwater drilling industry continues to require increased oversight of cementing programs and cement operations. A deepwater cementing technical specialist team was created to provide reviews and oversight of deepwater cement programs worldwide. Deepwater cementing specialists were selected from within the organization and the initiative was introduced to operations in the first quarter of 2011. The team provides an additional level of peer review of all deepwater cementing programs. The purpose of the peer review is to support the engineer’s program design and to verify that the program is in compliance with internal standards, client standards, and applicable regulatory requirements. If required, the team will act as a liaison for the operations personnel and additional experts on critical jobs. The reviews are documented so that all communication can easily be tracked.
The main objective of the team is to provide a proactive approach to identify risks early in the design phase and elevate the risks to the appropriate levels of management so that appropriate actions can be taken. The goal is to review all deepwater cement programs before submitting the final procedures for operations.
Sharing worldwide knowledge and adding to the worldwide knowledge base is necessary as new challenges are faced while drilling and cementing offshore wells in deep and ultradeep waters. Risks and potential hazards may be recognized long before the job execution—giving sufficient time to change, improve, and enhance the cementing design. Several examples are given for job designs that have been improved prior to execution. As a result of this initiative, a continuous improvement of job procedures is being observed worldwide, resulting in designs with a higher likelihood of achieving the job objectives, and avoiding unnecessary, costly remedial work.
Improving Cement Bonding and Zonal Isolation in Gas Wells Located in Southern Chile
Authors: Ficetti S. , Fontana H. 
Published: June 2012

Abstract
This work describes some technologies that have been applied in several wells in southern Chile to improve zonal isolation between different reservoir sections and minimize unwanted water production; an excellent cement bond is a key requirement. There are several challenges to the success of a cement job: the presence of gas-bearing zones in the wellbore that can destabilize the cement system causing it to fail, the presence of formations sensitive to filtrates from the drilling fluids and cement, and the climatic conditions in southern Chile during winter. In addition to these factors, the well needs to be cemented without generating any formation damage that could impair the well productivity.
The paper describes a multiwell solution consisting in the utilization of a solid gas migration (SGM) technology that, combined with a high-performance cement system and an engineered train of preflushes, allows achieving the ultimate goal of obtaining excellent cement quality and minimum formation damage. The SGM technology is suitable for use at very low ambient temperatures, and it provides effective gas-tight properties while minimizing the fluid loss of the slurry. The solution has proved to be extremely effective in controlling gas migration, even under extreme situations where neighboring wells presented serious sustained casing pressure (SCP) problems.
The novel SGM technology utilized also allows improvements in logistics by reducing the preparation time and equipment requirements for the job, thus providing a more sustainable well construction process. In addition, the cold-tolerant additives used provide significant value when preventing nonproductive time at the wellsite and, at the same time, eliminating the disposal of mix water containing liquid additives degraded because of the freezing cycles.
To date, more than 20 wells, with gas severity ranging from moderate to high, have been successfully cemented using this approach. The paper provides details of the engineering approach and examples, including cement logs.
Is it Time to Focus on Unconventional Resources?
Authors: Rajnauth J. 
Published: June 2012

Abstract
Trinidad and Tobago is a small country and our remaining known reserves now stand at 570 million barrels of oil and about 27 trillion cubic feet of gas. These reserves are both on land and offshore. The challenge of ensuring long-term growth of the energy sector has been great. This country has been endowed with energy resources and as a result, oil and natural gas play a central role in the socio-economic development of the country. Simultaneously they provide the necessary infra-structural economic base for the country becoming an attractive host for foreign investments in the energy sector.
In the face of declining crude oil production, relatively modest natural gas prices and no deepwater success to date, the development of our unconventional resources should now be placed into the forefront of our energy future. The large volume and long-term potential of our unconventional resources pose a big challenge today but increasing prices and improved technology is the key to their development in the future. The current worldwide trend is a move from conventional to unconventional resources due to technology advances.
This paper will evaluate the potential of developing our unconventional resources which include heavy oil, tar sands, tight sands and gas hydrates. The demand for oil and natural gas will continue to increase for the foreseeable future and we must now rely on unconventional resources to fill the gap between demand and supply. This analysis looks at the implications for the future and the technologies required for developing our unconventional resources. The research required and the technology advancement would also be discussed.
Factors Affecting the Uptake of Anti-Malarial Drugs by Children in Public
Primary Health Facilities in Cross River State, Nigeria
Authors: Ezedinachi Emmanuel , Odey Friday , Ameh Soter , Oduwole Olabisi , Esu Ekpereonne , Ejemot-Nwadiaro Regina , Ntadom Godwin , Etokidem Aniekan , Udoh Ekong , Asiegbu Vivian , Ugot Iyam , Asuquo Patrick , Alaribe Ambrose , Charles Joe , Nwokolo Ernest , Meremikwu Martin 
Published: June 2012

Background:
Despite the supply of artemisinin-based combination therapy (ACT) drugs to public health
facilities in Nigeria, the uptake of these drugs appear to have remained suboptimal with low improvement in childhood
morbidity and mortality.

Aim:
To use a controlled study to estimate the factors affecting the uptake of ACT in public health facilities in Cross River
State (CRS), Nigeria.

Methods:
The design of this study was cross sectional analytical. The study was carried out in two sites, Akpabuyo
(experimental) and Obudu (control) Local Government Areas (LGA) in the south and northern parts of CRS, Nigeria,
respectively. Multidisciplinary research team consists of health professionals, biomedical and social scientists who
worked with staff of the target facilities. Validated semi-structured questionnaires were administered by trained
interviewers on respondents of consecutive households selected by multi-stage sampling procedure.

Results:
A total of 1250 households (588 in Akpabuyo and 662 in Obudu LGAs) were assessed. More informants in
Obudu had formal education than in Akpabuyo (p<0.0001). Mortality of U5 children was higher in Akpabuyo. Stepwise
regression analysis showed that farmers (p = 0.009) and people without formal education (p = <0.0001) were less likely
than older age group (p = <0.0001) to access anti-malaria drugs in Akpabuyo. Religious beliefs (p=0.003) also predicted
uptake of ACTs in Obudu.

Conclusion:
Informants' occupation, age, education and religious beliefs were key determinants of uptake of ACTs in
public health facilities in Nigeria. We recommend targeted malaria education programmes to explore the belief systems in
treating fevers in children in this population.
Variability of Presentations and CT-Scan Findings in Children with Neurocysticercosis
Authors: Gauchan E , Malla T , Basnet S , Rao K S 
Published: June 2012

Background Neurocysticercosis is one of the common neurological morbidities in childhood. Objectives To find the commonest mode of presentation of this disorder in children. The study also aims to find out the age at which it commonly occurs, commonest site affected in the brain and the ethnic group and region most commonly affected in Western Nepal. Methods Retrospective hospital based study carried out in the Department of Pediatrics, Manipal Teaching Hospital, Pokhara from June 2004 to June 2009. Results Over the period of five years, 678 patients were admitted for seizures; out of which 109 patients were diagnosed as having neurocysticercosis (16%). Out of them, 66 (60.5%) were males and 43 (39.4%) were females. The age of presentation varied from 18 months to 16 years, with mean age 9.77 years. The most common age of presentation was between 6-10 years (n=47; 43.1%) and 11-15 years (n=47; 43.1%).Maximum number of patients were from Kaski district (n=41; 37.6%) followed by Syangja (n=34; 31.1%).The commonest presentation was with seizures (n=85; 77.9 %); generalised seizures was present in 45 patients (52%). Psychiatric manifestations were present in 3 patients (2.7%). The lesions were found mostly in the parietal region (n=65; 59.6 %). Most of the lesions were single (n=89; 81.6%). Out of 109 patients, 74 patients (67.8%) improved without any recurrence of symptoms on two years follow-up. ConclusionNeurocysticercosis is a preventable zoonotic disease which results in significant morbidity in children where sanitary measures are inadequate. Any child presenting with a first episode, afebrile seizure should be screened for neurocysticercosis provided other common causes are ruled out.DOI: http://dx.doi.org/10.3126/kumj.v9i2.6281 Kathmandu Univ Med J 2011;9(2):17-21