bluuebunny/crossref_metadata_2025_split huggingface dataset:
Progress in demystification of adhesion G protein-coupled receptors
Authors: Liebscher Ines , Schöneberg Torsten , Prömel Simone 
Published: April 2013

Abstract
Adhesion G protein-coupled receptors (aGPCR) form the second largest class of GPCR. They are phylogenetically old and have been highly conserved during evolution. Mutations in representatives of this class are associated with severe diseases such as Usher Syndrome, a combined congenital deaf-blindness, or bifrontal parietal polymicrogyria. The main characteristics of aGPCR are their enormous size and the complexity of their N termini. They contain a highly conserved GPCR proteolytic site (GPS) and several functional domains that have been implicated in cell-cell and cell-matrix interactions. Adhesion GPCR have been proposed to serve a dual function as adhesion molecules and as classical receptors. However, until recently there was no proof that aGPCR indeed couple to G proteins or even function as classical receptors. In this review, we have summarized and discussed recent evidence that aGPCR present many functional features of classical GPCR, including multiple G protein-coupling abilities, G protein-independent signaling and oligomerization, but also specific signaling properties only found in aGPCR.
The unresolved puzzle why alanine extensions cause disease
Authors: Winter Reno , Liebold Jens , Schwarz Elisabeth 
Published: April 2013

Abstract
The prospective increase in life expectancy will be accompanied by a rise in the number of elderly people who suffer from ill health caused by old age. Many diseases caused by aging are protein misfolding diseases. The molecular mechanisms underlying these disorders receive constant scientific interest. In addition to old age, mutations also cause congenital protein misfolding disorders. Chorea Huntington, one of the most well-known examples, is caused by triplet extensions that can lead to more than 100 glutamines in the N-terminal region of huntingtin, accompanied by huntingtin aggregation. So far, nine disease-associated triplet extensions have also been described for alanine codons. The extensions lead primarily to skeletal malformations. Eight of these proteins represent transcription factors, while the nuclear poly-adenylate binding protein 1, PABPN1, is an RNA binding protein. Additional alanines in PABPN1 lead to the disease oculopharyngeal muscular dystrophy (OPMD). The alanine extension affects the N-terminal domain of the protein, which has been shown to lack tertiary contacts. Biochemical analyses of the N-terminal domain revealed an alanine-dependent fibril formation. However, fibril formation of full-length protein did not recapitulate the findings of the N-terminal domain. Fibril formation of intact PABPN1 was independent of the alanine segment, and the fibrils displayed biochemical properties that were completely different from those of the N-terminal domain. Although intranuclear inclusions have been shown to represent the histochemical hallmark of OPMD, their role in pathogenesis is currently unclear. Several cell culture and animal models have been generated to study the molecular processes involved in OPMD. These studies revealed a number of promising future therapeutic strategies that could one day improve the quality of life for the patients.
When stable RNA becomes unstable: the degradation of ribosomes in bacteria and beyond
Authors: Maiväli Ülo , Paier Anton , Tenson Tanel 
Published: April 2013

Abstract
This review takes a comparative look at the various scenarios where ribosomes are degraded in bacteria and eukaryotes with emphasis on studies involving Escherichia coli and Saccharomyces cerevisiae. While the molecular mechanisms of degradation in bacteria and yeast appear somewhat different, we argue that the underlying causes of ribosome degradation are remarkably similar. In both model organisms during ribosomal assembly, partially formed pre-ribosomal particles can be degraded by at least two different sequentially-acting quality control pathways and fully assembled but functionally faulty ribosomes can be degraded in a separate quality control pathway. In addition, ribosomes that are both structurally- and functionally-sound can be degraded as an adaptive measure to stress.
Molecular function of the prolyl cis/trans isomerase and metallochaperone SlyD
Authors: Kovermann Michael , Schmid Franz X. , Balbach Jochen 
Published: April 2013

Abstract
SlyD is a bacterial two-domain protein that functions as a molecular chaperone, a prolyl cis/trans isomerase, and a nickel-binding protein. This review summarizes recent findings about the molecular enzyme mechanism of SlyD. The chaperone function located in one domain of SlyD is involved in twin-arginine translocation and increases the catalytic efficiency of the prolyl cis/trans isomerase domain in protein folding by two orders of magnitude. The C-terminal tail of SlyD binds Ni2+ ions and supplies them for the maturation of [NiFe] hydrogenases. A combined biochemical and biophysical analysis revealed the molecular basis of the delicate interplay of the different domains of SlyD for optimal function.
Confucian virtues and Chinese adolescent development: a conceptual review
Authors: Shek Daniel T.L. , Yu Lu , Fu Xiao 
Published: April 2013

Abstract
Despite the fact that different Chinese communities have already undergone industrialization and urbanization, Confucian virtues are still regarded as developmental ideals in Chinese culture. Unfortunately, while Confucian virtues are commonly discussed under Chinese philosophies, they are rarely examined in the context of developmental research. In this paper, several key Confucian virtues are discussed, including loyalty (“zhong”), filial piety (“xiao”), benevolence (“ren”), affection (“ai”), trustworthiness (“xin”), righteousness (“yi”), harmony (“he”), peace (“ping”), propriety (“li”), wisdom (“zhi”), integrity (“lian”) and shame (“chi”). These Chinese traditional virtues are also linked to the concepts of character strengths and positive youth development constructs highlighted in Western culture. It is argued that Confucian virtues provide an indigenous conceptual framework to understand character strengths and positive youth development in Chinese culture. Furthermore, when service leadership is considered in Chinese contexts, these virtues should be regarded as important cornerstones.
A heat source reconstruction formula from single internal measurements using a family of null controls
Authors: Garcia Galina C. , Osses Axel , Tapia Marcelo 
Published: April 2013

Abstract.
We consider the inverse problem of determining the spatial dependence of the source term in a heat equation in assuming known,
from a single internal measurements of the solution in . The purpose of this paper is to
establish a reconstruction formula for similar to the one obtained by M. Yamamoto in “Stability, Reconstruction formula and regularization for an inverse source hyperbolic
problem by a control method”, Inverse Problems 11 (1995), 481–496, for hyperbolic equations using exact controls, and generalized here for parabolic equations. The reconstruction formula is
associated to a family of exact controls indexed by . We perform numerical
simulations in order to illustrate the feasibility, accuracy and stability of the proposed reconstruction formula.
A numerical study of
heuristic parameter choice rules for
total variation regularization
Authors: Kindermann Stefan , Mutimbu Lawrence D. , Resmerita Elena 
Published: April 2013

Abstract.
We present a numerical study of heuristic (noiselevel-free)
regularization parameter choice rules for linear inverse problems with total variation regularization. Such type of
regularization is frequently employed in image and signal processing tasks, such as denoising or
deblurring. We review convergence results for total variation regularization and
propose some generalizations of two well-known heuristic parameter choice rules, the
quasi-optimality principle and the Hanke–Raus rules. We investigate the feasibility of these rules using different concepts of convergence such as
convergence in the Bregman distance and strict convergence in one and two dimensions by numerical simulation.
Diagnostic problems in case of twin pregnancies: US vs. MRI study
Authors: Bekiesinska-Figatowska Monika , Herman-Sucharska Izabela , Romaniuk-Doroszewska Anna , Jaczynska Renata , Furmanek Mariusz , Bragoszewska Hanna 
Published: April 2013

Abstract

Aim: To present an experience with twin pregnancies underlining the impact of magnetic resonance imaging (MRI) on diagnosis and management.

Methods: There were 17 cases of twin pregnancies: nine monochorionic [including four monochorionic diamniotic and five monochorionic monoamniotic (conjoined twins)] and eight dichorionic. The MRI examinations were performed between 19 and 39 weeks of gestational age in two centers using 1.5 T scanners (GE Signa Excite and GE Signa HDxt; GE Healthcare, Waukesha, WI, USA), always after ultrasound (US). In the first period of our activity, SSFSE sequence in T2-weighted images (SSFSE/T2WI) was the main diagnostic tool supported by TSE or GRE T1-weighted images (T1WI). After upgrading the scanners, diffusion-weighted imaging (DWI), steady-state free precession (FIESTA), and echoplanar GRE imaging (EPIGRE) became available.

Results: In 11 cases (64.7%), MRI was superior to US and supplied additional information, including two cases in which pathology of the second twin suspected on US was ruled out on the basis of MRI. In six cases (35.3%) MRI confirmed US diagnosis and brought no new data.

Conclusion: MRI offers more detailed assessment of fetal pathology in cases of twin pregnancies, including conjoined twins, in which sonographic evaluation is more difficult than in single cases.
Of the rookery distribution differences in northern fur seals and Steller sea lions in the waters of the Russian far east
Authors: Wada Kazuo , Hoshino Hiroshi , Kuboshima Emi , Wada Akihiko 
Published: April 2013

Abstract
We investigated factors influencing differences in the rookery distribution patterns between northern fur seals and Steller sea lions in the waters of the Russian far east. The limited distribution of northern fur seal rookeries observed during 1991–2001 resulted from the need for shallow tide pools near the shore for pups to practice swimming. In addition, the large and concentrated populations of the seals required large flat areas and a high degree of natal site fidelity. In contrast, in the case of Steller sea lion rookeries observed along the Kuril islands in 2001, the pups were able to swim under maternal care, and their populations were smaller and had a lower degree of natal site fidelity. So, from our observations, their rookeries, unlike those of northern fur seals, are therefore widely distributed across diverse topographical conditions in the waters of Russian far east.
Crystal and molecular structure of bis(4-dimethylamino-3-nitrophenyl)tellurium dichloride
Authors: Beckmann Jens , Dakternieks Dainis , Duthie Andrew , Mitchell Cassandra 
Published: April 2013

Abstract
Single crystal X-ray crystallography revealed that the title compound [(4-Me2N)(3-O2N)C6H3]2TeCl2 is associated in the solid state mainly by intermolecular secondary Te‧‧‧O contacts.
Effect of reinforcement percentage on wear behavior of SiCp reinforced ZA43 alloy metal matrix composites
Authors: Marigoudar Rajaneesh N. , Sadashivappa Kanakuppi 
Published: April 2013

Abstract
Metal matrix composites (MMCs) are characterized by high specific strength and stiffness. Light metal alloys are reinforced with hard ceramic particles, which show better properties compared to monolithic alloys. ZA43 MMCs are fabricated by stir casting technique by reinforcing preheated silicon carbide particles (SiCp). Wear behavior of ZA43 MMCs is evaluated by conducting dry sliding wear test using a pin-on-disc wear test rig. The tests were conducted for varying loads of 9.81, 19.62, 29.43 and 39.24 N and sliding disc speeds of 2.12, 2.93, 3.66, 4.39 and 5.13 m/s at constant time of 15 min. The results reveal that the wear resistance property of the composite increases as the percentage of reinforcement increases. It was also observed that volume loss increases with increasing applied load and sliding speed. The tested samples were examined and analyzed by taking scanning electron micrographs. The dominating wear mechanisms observed were delamination, scissoring of the abrasive particle, pullout of particle, smearing of the surface and abrasion.
Structure-Electrical Transport Property Relationship of Anisotropic iPP/CNT Films
Authors: Kalakonda Parvathalu , Daly Michael , Xu Kaikai , Cabrera Yaniel , Judith Robert , Iannacchione Germano S. , Georgiev Georgi Y. , Cebe Peggy 
Published: April 2013

ABSTRACTThe internal micro/nano-structure of anisotropically oriented polymer/CNTs composites determines their macroscopic properties. However, the connections between the two are not fully understood. The varying of CNT concentration, preparation method, and a thermodynamic parameter (e.g. temperature) can all play interconnected role. In this work, the macroscopic electrical conductivity was measured perpendicular to the film thickness of an insulating polymer (isotactic PolyPropylene, iPP) and a nano-composite of iPP with 5 weight percent of CNT. The thin films studied were sheared (anisotropically nano-structured) and non-sheared (with random internal structure). In general the effect of melt shearing induces anisotropy on the electrical transport properties of the iPP/CNT films in directions parallel and perpendicular to the direction of orientation. Our results show that for the pure iPP, resistivity slightly increases with shear at higher temperatures. When CNTs are introduced, there is a large difference between the resistivity of the sheared and non-sheared nanocomposite. The sheared PNCs when the CNTs are aligned parallel to each other, have higher resistivity, which is possibly due to the higher concentration at which the percolation threshold occurs in this arrangement. The resistivity decreases overall, as the temperature increases from 0 to 50 °C. These results show that CNTs can be used to control and fine tune the desired macroscopic physical properties of nanocomposites, by concentration and orientation, such as electrical conductivity, for applications where such properties are necessary.
Formation Testing and Sampling in Low Mobility Heavy Oil Formations of the Eastern Desert, Egypt
Authors: Edelman Jeff , Shah Shabbir H. , Weinheber Peter , Ahmed Ramy , Roumani Izzat , Maghrabia Karim 
Published: April 2013

Abstract
The Arta fields of Egyptian Eastern Desert are operated by Petrodara, a joint venture of Transglobe Energy and Egyptian General Petroleum Corporation (EGPC). The main producing horizon is the Nukhul and formation pressure measurements are critical in this poorly sorted conglomerated marl in order to understand and model depletion. However, low permeability and high viscosity oils contributed to a very low mobility environment that presented considerable challenges to Wireline Formation Tester (WFT) tools. Extensive testing programs resulted in an excessive amount of tests that were unusable, being classified as ‘dry’, ‘tight’ or ‘supercharged’. This low mobility environment also complicated the requirement for PVT samples acquired with the WFT tools. Normal testing operations resulted in very high drawdowns that sampled below formation pressure and caused emulsions with the filtrate of the water based drilling fluid.
In this paper we discuss how the Operator and the Service Company combined to employ fit for purpose WFT techniques to acquire accurate formation pressure data and PVT quality oil samples. Most of our discussion will be based on understanding the dynamics of pretesting in low permeability formations and how the optimal tool and pretest design can produce results where previous attempts have failed. Specifically we consider the newest ‘pretest only’ WFT that provides very fine control over pretest rate and volume and allows precise test design that is not possible with conventional WFT tools. Additionally, we demonstrate the application of best practices and lessons learned from worldwide sampling operation to acquire PVT quality heavy oil samples.
Application of a Numerical Simulation Model for Work over Plans Assessment Prior Operations and Determination of Best Well Intervention Technique for Production Enhancement
Authors: Abugren Yosra Yousef , Joshi Sameer , Steene Marie V. , Thabet Enas 
Published: April 2013

Abstract
This paper describes the application of a new numerical model to simulate any work over plans in order to assess the work over efficiency and the well productivity enhancement, prior to operations commencement.
A case study is discussed, where an operator in Egypt had a plan to improve the productivity of an oil well producing from a multi-layer reservoir, where a low productivity layer had been previously identified and characterized by multiple techniques.
It was critical for the operator to enhance the productivity across this layer and to identify the appropriate remedial action (water shut off, re-perforate, or stimulation) that could impact the whole field production performance. The operator had decided to re-perforate and add new perforations to the low productivity layer.
The numerical simulation model was hence applied to assess work over techniques and to determine the most suitable remedial action for implementation. The simulation result of reperforation and adding new perforations showed water cut drop by 6% with an increase in oil rate by 538 b/d and in water rate by 348 b/d compared to the initial profile identified by production logging. The result of the numerical simulation model suggests that the low productivity layer should be considered as a candidate for stimulation (fracturing/acidizing).
When the operator attempted to re-perforate the low productivity layer, the production performance after the re-perforation did not show a major improvement, as the water cut decreased by 6% only with a small gain in oil rate, which is in agreement with the simulation model outcome.
The operator understood the reason for the field wide low productivity from this layer and hence obtained a key to unlocking the reserves contained in this layer across the whole field in future field development plans.
Case Study in Upgrading Capability of a Crude Oil Pipeline for Maximum Transportation Capacity
Authors: Abdou Hesham A. 
Published: April 2013

Abstract
Since November 1984 The 406.4 mm x 166 km has run from Meleiha field at Egypt&#39;s Western Desert to El-Hamra terminal on the coast of the Mediterranean Sea (Figure 1). Its original capacity was 100,000 barrels oil per day (BOPD) using two pumping stations. Planned pumped flow rate increased to 177,000 BOPD when maximum allowable working pressure (MAWP) reduced from 1463 psi to 950 psi. This paper shows how to increase flow rates without reaching MAWP, two methods are recommended: 1) loop the existing pipeline using a 406.4 mm x 56 km pipe. 2) Use a drag reducing agent (DRA) to reduce hydraulic friction losses and total dynamic pressure (TDP) thereby pumping more with reduced initial pumping pressure at Meleiha. Mathematical models are designed to simulate pumping operation through the whole system, with TDP predicted for three pipeline cases: 1) Normal case without both looping and DRA. 2) Oil pumping without DRA and with looping. 3) Oil pumping with both looping and DRA.
Estimation of Annulus Pressure Fluids Kick for Vertical Well Using Moore Method and Integrated Numerical Simulation
Authors: Marbun B. T. , Shidiq A. M. 
Published: April 2013

Abstract
The pressure analysis in annulus to overcome well kick and the well control procedure execution are main concern, particularly when the top of influx reaches the casing shoe. Besides, time and gas volume determination when bubble of gas reaches the surface are importance in executing well control operation with conventional method. The data should be calculated and considered to determine the most appropriate killing well method.
Annulus pressure will increase continuously until eventually reach highest value and volume of pit gain and also reach the maximum at the time of influx reach the surface. Sometime, to circulate all of the influx, it is required sufficient time. Considering the worst circumstances, drilling crews should prepare their mental and the correct strategy to overcome it. There is a fatal risk when well control fails to do, not only loss of rig equipments, but also the life of drilling personel. Thus, the strategy must be done safely. The annulus pressure determination in this research uses the Moore equation. The result of the calculation will be compared to the result of the integrated numerical simulation. Driller Method and Wait &amp; Weight Method will be applied in Moore equation and simulator. Based on comparison of the calculation result, the safer well control method can be chosen optimally.
Determination of Drainage Area and Shape Factor of Vertical Wells in Naturally Fracture Reservoir with Help Well testing and Developed IPR Curve
Authors: Sadeghi Mohammad , Shadizadeh Seyed Reza , Ahmadi Mohammad Ali 
Published: April 2013

Abstract
Shape Factor and drainage area in hydrocarbon reservoir are of the necessary and influencing factors on evaluation and optimization of drilling operation in oil fields. There are numerous methods to calculate the reservoir average pressure in conventional and sandstone reservoirs in that shape and drainage area of the reservoir are of important variables. On the other hand, these relations especially set for sandstone reservoirs and have limited usage in natural fracture reservoirs. This research demonstrates an approach to figure out shape factor and drainage area of wells in carbonated and naturally fractured reservoirs in all pressure and fluidity conditions. To assess this goal, results of well testing are carried out both for development of inflow performance curve and finding the drainage area. To make sure about the validity and preciseness of this method, it was investigated against the data from a well in a natural fracture field and the results were compared with those of other methods. Results dictated that the new approach can provide us with more precise and correct routes for the shape of the well in naturally fractured reservoirs. The suggested approach in this research needs production test data that has been optimized by well testing data for naturally fractured reservoirs. Additionally, this approach implemented to the draw down test and Tiab direct technique which is related to Warren and Root solution. What's more, this approach is reliable for all vertical wells in naturally fractured reservoirs (NFRs) with accessible production test data and well testing.